REKAYASA BIOLOGIS SUMBERDAYA HAYATI

REKAYASA BIOLOGISSUMBERDAYA HAYATI

KETAHANAN SUMBERDAYA ALAM

DAN PANGAN

smno.psdl.ppsub

• Manipulating and engineering genetic material in the lab may represent the best hope for increasing agricultural

production further without destroying more natural lands.• But many people remain uneasy about genetically

engineering crop plants and other organisms.Diunduh dari: www.instruction.greenriver.edu/.../BW_EssentialCh06Lecture.ppt ……

20/12/2012

MODIFIKASI GENETIK PANGAN

Genetically modified foods (GM foods, or biotech foods) are foods derived from genetically modified organisms (GMOs),

specifically, genetically modified crops. GMOs have had specific changes introduced into their DNA by

genetic engineering techniques.

These techniques are much more precise than mutagenesis (mutation breeding) where an organism is exposed to radiation or

chemicals to create a non-specific but stable change.

Other techniques by which humans modify food organisms include selective breeding; plant breeding, and animal breeding,

and somaclonal variation.

Diunduh dari: http://en.wikipedia.org/wiki/Genetically_modified_food…… 22/12/2012

• Genetic engineering (GE) = directly manipulating an organism’s genetic material in the lab by adding, deleting, or changing

segments of its DNA• Genetically modified (GM) organisms = genetically engineered

using recombinant DNA technology• Recombinant DNA = DNA patched together from DNA of multiple

organisms (e.g., adding disease-resistance genes from one plant to the genes of another)

Diunduh dari: www.instruction.greenriver.edu/.../BW_EssentialCh06Lecture.ppt …… 20/12/2012

REKAYASA GENETIK MENGGUNAKAN

DNA - REKOMBINAN

Diunduh dari: http://www.nobelkepu.org.cn/english/life/136898.shtml …… 22/12/2012

What is transgenic food?Transgenic food are those directly made from or processed from the species (animals, plants and microorganisms, etc.) which can produce substances possessing highly effective expressions, such

as polypeptide and protein, after one or several types of exogenous genes are transferred into it through the means of genetic

engineering.The first category----transgenic plant food

productThere are various kinds of transgenic plant foods, such as high protein wheat used to bake breads. To reverse the situation that wheat in the current market contains low rate of protein, protein

genes possessing highly effective expressions are transferred into wheat, so that bread made from the wheat can be of more

nutritious value.

• Genes moved between organisms are transgenes, and the organisms are transgenic.

• These efforts are one type of biotechnology, the material application of biological science to

create products derived from organisms.Diunduh dari: www.instruction.greenriver.edu/.../BW_EssentialCh06Lecture.ppt ……

20/12/2012

TRANSGENE & BIOTEKNOLOGI

Transgenosis technology is a kind of modern technology in molecular biology, which is used to transfer genes from one species into another so as to reconstruct the genetic materials of the

receiving species for the improvement of its properties, quality of nutrition in line with the

need of human beings. The transgenic species as immediate food and

food processed from transgenic species are called transgenic food.

Diunduh dari: http://www.nobelkepu.org.cn/english/life/136898.shtml…… 22/12/2012

• They are similar:• We have been altering crop genes (by artificial

selection) for thousands of years.• There is no fundamental difference: both

approaches modify organisms genetically.

• They are different:

• GE can mix genes of very different species.• GE is in vitro lab work, not with whole organisms.• GE uses novel gene combinations that didn’t come

together on their own.


REKAYASA GENETIK vs. PEMULIAAN TRADISIONAL

Some GM foods

Golden rice:

Enriched with

vitamin A.

But too much hype?

Bt crops: Widely used

on U.S. crops.But

ecological concerns?

Ice-minus strawberries: Frost-resistant bacteria

sprayed on.Images alarmed public.

FlavrSavr tomato: Better taste?

But pulled from market.


Some GM foods

Bt sunflowers: Insect resistant.

But could hybridize with wild relatives to create “superweeds”?

Terminator seeds: Plants kill their own

seeds. Farmers forced

to buy seeds each year.

Roundup-Ready crops: Resistant to Monsanto’s

herbicide. But encourages more herbicide use?

StarLink corn: Bt corn variety.

Genes spread to non-GM corn; pulled from market.


• Although many early GM crops ran into bad publicity or other problems, biotechnology is already transforming the

U.S. food supply.

• Two-thirds of U.S. soybeans, corn, and cotton are now genetically modified strains.

Diunduh dari: http://www.nyu.edu/classes/jaeger/genetically_modified_foods.htm…… 22/12/2012

PREVALENSI PANGAN TRANSGENIK

Health concerns and potential food hazards

Health risks associated with genetically modified foods are concerned with toxins, allergens, or genetic hazards. The

mechanisms of food hazards fall into three main categories (Conner et al., 1999):

1. Inserted genes and their expression products2. Secondary and pleiotropic effects of gene expression3. Insertional mutagenesis resulting from gene

integration


For example, bean plants that were genetically modified to increase cysteine and methionine content were discarded after the discovery that the expressed protein of the transgene was highly

allergenic. (Butler et al., 1999)

1. Are there health risks for people?2. Can transgenes escape into wild plants, pollute ecosystems,

harm organisms?3. Can pests evolve resistance to GM crops just as they can to

pesticides?4. Can transgenes jump from crops to weeds and make them

into “superweeds”?5. Can transgenes get into traditional native crop races and

ruin their integrity?

ORGANISME TRANSGENIK


Diunduh dari: http://www.nyu.edu/classes/jaeger/genetically_modified_foods.htm…… 22/12/2012

The potential risks accompanied by disease resistant plants deal mostly with viral

resistance. It is possible that viral resistance can lead to the formation of new viruses, and therefore

new diseases. It has been reported that naturally occurring viruses can recombine with viral fragments

that are introduced to create transgenic plants, forming new viruses.

Additionally, there can be many variations of this newly formed virus. (Steinbrecher,

1996)

• These questions are not fully answered yet.

• In the meantime…

Should we not worry, because so many U.S. crops are already GM and little drastic

harm is apparent?

Or should we adopt the precautionary principle, the idea

that one should take no new action until its

ramifications are understood?


ORGANISME TRANSGENIK

• Should scientists and corporations be “tinkering with” our food supply?

• Are biotech corporations testing their products adequately, and is outside oversight adequate?

• Should large multinational corporations exercise power over global agriculture and small farmers?

Diunduh dari: http://www.nyu.edu/classes/jaeger/genetically_modified_foods.htm …… 20/12/2012

PRODUK-PRODUKTRANSGENIK


RISKS AND CONTROVERSY

With all this new technology comes question and fear. What are the risks of "tampering with Mother Nature"?

What effects will this have on the environment? Are there health concerns consumers should be aware of?

Is recombinant technology really beneficial?

The following section will address some major concerns about the risks involved with genetically modified foods and recombinant technology, touching up environmental

risks as well as health risks.

ProjectedDisadvantages

Need less fertilizer

Need less water

More resistant to insects,plant disease, frost, anddrought

Faster growth

Can grow in slightly saltysoils

Less spoilage

Better flavor

Less use of conventionalpesticides

Tolerate higher levels ofpesticide use

Higher yields

ProjectedAdvantages

Trade-OffsGenetically Modified Food and Crops

Irreversible andunpredictable genetic and ecological effects

Harmful toxins in foodFrom possible plant cellMutations

New allergens in food

Lower nutrition

Increased evolution ofPesticide-resistantInsects and plant disease

Creation of herbicide-Resistant weeds

Harm beneficial insects

Lower genetic diversity


Viewpoints: Genetically modified foods

Indra Vasil Ignacio Chapela

“We should expect fundamental alterations in ecosystems with the release of transgenic

crops… We are experiencing a global experiment without

controls.”

“Biotech crops are already helping to conserve valuable natural resources, reduce the use of

harmful agro-chemicals, produce

more nutritious foods, and promote economic

development.”


• Native cultivars of crops are important to preserve, in case we need their genes to overcome future pests or pathogens.

• Diversity of cultivars has been rapidly disappearing from all crops throughout the world.

Diunduh dari: http://en.wikipedia.org/wiki/Crop_diversity …… 22/12/2012

MELESTARIKAN KEANEKA-RAGAMAN TANAMAN

Crop diversity is the variance in genetic and phenotypic characteristics of plants used in agriculture.

Crops may vary in seed size, branching pattern, in height, flower color, fruiting time, or flavor.

They may also vary in less obvious characteristics such as their response to heat, cold or drought, or their ability

to resist specific diseases and pests. It is possible to discover variation in almost every conceivable trait, including nutritional qualities,

preparation and cooking techniques, and of course how a crop tastes. And if a trait cannot be found in the crop

itself, it can often be found in a wild relative of the crop; a plant that has similar species that have not been farmed

or used in agriculture, but exist in the wild.


Seed banks preserve seeds, crop varieties

– Seed banks are living museums of crop diversity, saving collections of seeds and growing them into plants every few years to renew the collection.

• Careful hand pollination helps ensure plants of one type do not interbreed with plants of another.


Animal agriculture: Livestock and poultry

• Consumption of meat has risen faster than population over the past several decades.


• Increased meat consumption has led to animals being raised in feedlots (factory farms), huge pens that deliver energy-rich food to animals housed at

extremely high densities.


PERTANIAN-TERNAK DAMPAK LINGKUNGANNYA

• Immense amount of waste produced, polluting air and water nearby

• Intense usage of chemicals (antibiotics, steroids, hormones), some of which persist in environment

• However, if all these animals were grazing on rangeland, how much more natural land would be converted for

agriculture?

Diunduh dari: http://www.dpi.vic.gov.au/agriculture/about-agriculture/newsletters-and-updates/newsletters/milking-the-weather/june/seasonal-preparation ……..……

22/12/2012

PERTANIAN-TERNAK DAMPAK LINGKUNGANNYA


• Energy is lost at each trophic level.• When we eat meat from a cow fed on grain, most of the grain’s

energy has already been spent on the cow’s metabolism.• Eating meat is therefore very energy inefficient.

Diunduh dari: http://www.the-food-pyramid.com/healthy-diet/food-pyramid/ …..…… 22/12/2012

PILIHAN PANGAN = PILIHAN ENERGI


The FOOD PYRAMID is a nutrition guide that is shaped like a pyramid.

It is separated in parts, with each segment depicting the suggested intake of a particular food group.

http://www.the-food-pyramid.com/wp-content/uploads/2011/11/harvard_food_pyramid.png

Grain feed input for animal output

• Some animal food products can be produced with less input of grain feed than others.


LAHAN DAN AIR UNTUK TERNAK

• Some animal food products can be produced with less input of land and water than others.


• The raising of aquatic organisms for food in controlled environments

• Provides 1/3 of world’s fish for consumption• 220 species being farmed

• The fastest growing type of food production

Diunduh dari: http://intecsciwri.wikidot.com/aquaculture …… 22/12/2012

AQUACULTURE


AquacultureThe cultivation of aquatic organisms. Some of the most common

organisms that are cultivated are salmon, trout, oysters, and clams.

AQUACULTURE• Fish make up

half of aquacultural production.

Molluscs and plants each

make up nearly 1/4.

• Global aquaculture

has been doubling about every 7 years.


1. Provides reliable protein source for people, increases food security2. Can be small-scale, local, and sustainable3. Reduces fishing pressure on wild stocks, and eliminates bycatch4. Uses fewer fossil fuels than fishing5. Can be very energy efficient


MANFAAT AKUAKULUR

Budidaya Ikan Lele di Gemolong Sragen Lele merupakan jenis ikan yang digemari masyarakat, dengan rasa yang lezat, daging empuk, duri teratur dan dapat disajikan dalam berbagai macam menu

masakan. PT. NATURAL NUSANTARA dengan prinsip K-3 (Kuantitas, Kualitas dan Kesehatan) membantu petani lele dengan paket produk dan teknologi.

Diunduh dari: http://merubahmimpi.blogspot.com/2011/01/budidaya-ikan-lele-di-gemolong-sragen.html …… 20/12/2012

http://4.bp.blogspot.com/_FNLVkNsZImI/TTsjnteEaKI/AAAAAAAAADk/QkYvzLOnQv0/s1600/71978379_4-KOEBUL-KOMONITAS-BUDIDAYA-IKAN-LELE-Dijual.jpg

DAMPAK LINGKUNGAN AKIBAT AKUAKULTUR

1. Density of animals leads to disease, antibiotic use, risks to food security.

2. It can generate large amounts of waste.3. Often animals are fed grain, which is not energy efficient.4. Sometimes animals are fed fish meal from wild-caught fish.5. Farmed animals may escape into the wild and interbreed with,

compete with, or spread disease to wild animals.

Diunduh dari: http://www.fao.org/docrep/006/y5098e/y5098e02.htm …… 22/12/2012


Aquaculture is the fastest growing food production sector in the World with annual growth in excess of 10 percent over the last two decades. Much of this

development has occurred in Asia, which also has the greatest variety of cultured species and systems. Asia is also perceived as the ‘home’ of aquaculture, as

aquaculture has a long history in several areas of the region and knowledge of traditional systems is most widespread.

• Transgenic salmon (top) can compete with or spread disease to wild salmon (bottom) when they escape

from fish farms.


DAMPAK LINGKUNGAN AKUAKULTUR

Highly efficient

High yield in smallvolume of water

Increased yieldsthrough cross-breeding and genetic engineering

Can reduce over-harvesting of conventional fisheries

Little use of fuel

Profit not tied to price of oil

High profits

Advantages

Large inputs of land, feed, And water needed

Produces large and concentrated outputs of waste

Destroys mangrove forests

Increased grain productionneeded to feed some species

Fish can be killed by pesticide runoff from nearby cropland

Dense populations vulnerable to disease

Tanks too contaminated touse after about 5 years

Disadvantages

Trade-Offs

Aquaculture


• Reduce use of fishmeal as a feed to reduce depletion of other fish

• Improve pollution management of aquaculture wastes

• Reduce escape of aquaculture species into the wild

• Restrict location of fish farms to reduce loss of mangrove forests and other threatened areas

• Farm some aquaculture species (such as salmon and cobia) in deeply submerged cages to protect them from wave action and predators and allow dilution of wastes into the ocean

• Set up a system for certifying sustainable forms of aquaculture

Solutions

More Sustainable Aquaculture


• Agriculture that can practiced the same way far into the future• Does not deplete soils faster than they form

• Does not reduce healthy soil, clean water, and genetic diversity essential for long-term crop and

livestock productionLow-input agriculture = small amounts of pesticides, fertilizers, water, growth

hormones, fossil fuel energy, etc.• Organic agriculture = no synthetic chemicals used. Instead, biocontrol, composting,

etc.

Diunduh dari: http://www.fftc.agnet.org/library.php?func=view&style=&type_id=4&id=20110808172707&print=1 …… 23/12/2012

PERTANIAN BERKELANJUTAN


Components of a Sustainable Soil Management System

PERTANIANORGANIK

• Small percent of market, but is growing fast– 1% of U.S. market, but growing 20%/yr

– 3–5% of European market, but growing 30%/yr

• Organic produce:• Advantages for consumers: healthier; environmentally better

• Disadvantages for consumers: less uniform and appealing-looking; more expensive

Diunduh dari: http://agritech.tnau.ac.in/org_farm/orgfarm_principles.html …… 23/12/2012


Principles in Organic Farming

PERTANIANORGANIK

PRINSIP KESEHATANOrganic Agriculture should sustain and enhance the health of soil, plant, animal, human and planet as one and indivisible.This principle points out that the health of individuals and

communities cannot be separated from the health of ecosystems - healthy soils produce healthy crops that foster the health of

animals and people.

Health is the wholeness and integrity of living systems. It is not simply the absence of illness, but the maintenance of physical, mental, social and ecological well-being. Immunity, resilience

and regeneration are key characteristics of health.

The role of organic agriculture, whether in farming, processing, distribution, or consumption, is to sustain and enhance the health

of ecosystems and organisms from the smallest in the soil to human beings. In particular, organic agriculture is intended to

produce high quality, nutritious food that contributes to preventive health care and well-being.

In view of this it should avoid the use of fertilizers, pesticides, animal drugs and food additives that may have adverse health

effects.


PERTANIANORGANIK

PRINSIP EKOLOGI

Organic Agriculture should be based on living ecological systems and cycles, work with them, emulate them and help sustain them.

This principle roots organic agriculture within living ecological systems. It states that production is to be based on ecological processes, and recycling. Nourishment and well-being are achieved through the

ecology of the specific production environment. For example, in the case of crops this is the living soil; for animals it is the farm ecosystem;

for fish and marine organisms, the aquatic environment.

Organic farming, pastoral and wild harvest systems should fit the cycles and ecological balances in nature. These cycles are universal but their

operation is site-specific. Organic management must be adapted to local conditions, ecology, culture and scale. Inputs should be reduced by

reuse, recycling and efficient management of materials and energy in order to maintain and improve environmental quality and conserve

resources.

Organic agriculture should attain ecological balance through the design of farming systems, establishment of habitats and maintenance of

genetic and agricultural diversity. Those who produce, process, trade, or consume organic products should protect and benefit the common

environment including landscapes, climate, habitats, biodiversity, air and water.


PERTANIANORGANIK

PRINSIP KEADILANOrganic Agriculture should build on relationships that ensure fairness

with regard to the common environment and life opportunities.Fairness is characterized by equity, respect, justice and stewardship of

the shared world, both among people and in their relations to other living beings.

This principle emphasizes that those involved in organic agriculture should conduct human relationships in a manner that ensures fairness at all levels and to all parties - farmers, workers, processors, distributors,

traders and consumers. Organic agriculture should provide everyone involved with a good quality of life, and contribute to food sovereignty and reduction of

poverty. It aims to produce a sufficient supply of good quality food and other products.

This principle insists that animals should be provided with the conditions and opportunities of life that accord with their physiology,

natural behavior and well-being.

Natural and environmental resources that are used for production and consumption should be managed in a way that is socially and

ecologically just and should be held in trust for future generations. Fairness requires systems of production, distribution and trade that are open and equitable and account for real environmental and social costs.


PERTANIANORGANIK

PRINCIPLE OF CAREOrganic Agriculture should be managed in a precautionary and

responsible manner to protect the health and well-being of current and future generations and the environment.

Organic agriculture is a living and dynamic system that responds to internal and external demands and conditions. Practitioners of organic agriculture can enhance efficiency and increase productivity, but this

should not be at the risk of jeopardizing health and well-being. Consequently, new technologies need to be assessed and existing

methods reviewed. Given the incomplete understanding of ecosystems and agriculture, care must be taken.

This principle states that precaution and responsibility are the key concerns in management, development and technology choices in

organic agriculture.

Science is necessary to ensure that organic agriculture is healthy, safe and ecologically sound. However, scientific knowledge alone is not

sufficient. Practical experience, accumulated wisdom and traditional and indigenous knowledge offer valid solutions, tested by time. Organic agriculture should prevent significant risks by adopting appropriate

technologies and rejecting unpredictable ones, such as genetic engineering.

Decisions should reflect the values and needs of all who might be affected, through transparent and participatory processes.


1. Chemical pesticides pollute, and kill pollinators, and pests evolve resistance.

2. GM crops show promise for social and environmental benefits, but questions linger about their impacts.

3. Much of the world’s crop diversity has vanished.4. Feedlot agriculture and aquaculture pose benefits and harm for the

environment and human health.

Diunduh dari: http://www.thefutureoffarming.org/home.html …… 23/12/2012

TANTANGAN PERTANIAN MASA DEPAN


Pesticide Action Network (PAN) is a global network working to eliminate the human and environmental harm caused by pesticides and to promote biodiversity based ecological agriculture. We are dedicated to protect the safety and health of people, and the environment from pesticide use and

genetic engineering.

1. Organic farming remains a small portion of agriculture.2. Human population continues to grow, requiring more food

production. 3. Soil erosion is a problem worldwide.4. Salinization, waterlogging, and other soil degradation problems

are leading to desertification.5. Grazing and logging, as well as cropland agriculture, contribute to

soil degradation.

Diunduh dari: http://www.adas.co.uk/Home/Sustainablecropmanagement/tabid/245/Default.aspx ……

23/12/2012



SUSTAINABLE CROP MANAGEMENTOne of the most significant challenges facing Mankind is the adequate provision of food from sustainable and profitable production systems within a context of high energy costs.

1. Biocontrol and IPM offer alternatives to pesticides.

2. Further research and experience with GM crops may eventually resolve questions about impacts, and allow us to maximize benefits while minimizing harm.

3. More funding for seed banks can rebuild crop diversity.

4. Ways are being developed to make feedlot agriculture and aquaculture safer and cleaner.



1. Organic farming is popular and growing fast.2. Green revolution advances have kept up with food demand so far.

Improved distribution and slowed population growth would help further.

3. Farming strategies like no-till farming, contour farming, terracing, etc., help control erosion.

4. Government laws, and government extension agents working with farmers, have helped improve farming practices and control soil degradation.

5. Better grazing and logging practices exist that have far less impact on soils.

Diunduh dari: http://www.essex.ac.uk/ces/research/susag/WhatissusagBa1.shtm …… 23/12/2012

SOLUSI PERTANIAN MASA DEPAN


An Assets-Based Model for Sustainability

Agricultural systems at all levels rely for their success on the value of services flowing from the total stock of assets

that they control. Five types of capital, natural, social, human, physical and financial, are now being addressed in

the literature :1. Natural capital2. Social capital 3. Human capital 4. Physical capital5. Financial capital.


AN ASSETS-BASED MODEL FOR SUSTAINABILITY

1. Natural capital produces nature’s goods and services, and comprises food (both farmed and harvested or caught from the wild), wood and fibre; water supply and regulation; treatment, assimilation and decomposition of wastes; nutrient cycling and fixation; soil formation; biological control of pests; climate regulation; wildlife habitats; storm protection and flood control; carbon sequestration; pollination; and recreation and leisure.

2. Social capital yields a flow of mutually beneficial collective action, contributing to the cohesiveness of people in their societies. The social assets comprising social capital include norms, values and attitudes that predispose people to cooperate; relations of trust, reciprocity and obligations; and common rules and sanctions mutually-agreed or handed-down. These are connected and structured in networks and groups.

3. Human capital is the total capability residing in individuals, based on their stock of knowledge skills, health and nutrition. It is enhanced by their access to services that provide these, such as schools, medical services, and adult training. People’s productivity is increased by their capacity to interact with productive technologies and with other people. Leadership and organisational skills are particularly important in making other resources more valuable.

4. Physical capital is the store of human-made material resources, and comprises buildings (housing, factories), market infrastructure, irrigation works, roads and bridges, tools and tractors, communications, and energy and transportation systems, that make labour more productive.

5. Financial capital is accumulated claims on goods and services, built up through financial systems that gather savings and issue credit, such as pensions, remittances, welfare payments, grants and subsidies.



The basic premise is that sustainable systems, whether farms, firms, communities, or economies, accumulate stocks of these five assets, thereby increasing the per capita endowments of all forms of capital over time. But unsustainable systems

deplete or run down these various forms, spending assets as if they were income, and so leaving less for future generations.



The assets-based model shows how farms and rural livelihoods take inputs of various types, including renewable assets, and transform these

to produce food and other desirable outputs.

These can be processed for home consumption, transformed through value-added processes for sale, or sold directly as raw product.

The inputs are shown as:1. Renewable natural capital – soil, water, air, biodiversity etc;2. Social and participatory processes – including both locally

embedded and externally-induced social capital, and partnerships and linkages between external organisations;

3. New technologies, knowledge and skills – both regenerative (eg legumes, natural enemies) and non-renewable (eg hybrid seeds, machinery);

4. Non-renewable or fossil-fuel derived inputs (eg fertilizers, pesticides, antibiotics);

5. Finance – credit, remittances, income from sales and grants.

Availability and access to these five inputs is shaped by a wide range of contextual factors (on the far left). These include unchanging ones (at least over the short-term), such as climate, agro-ecology, soils, culture;

and dynamic economic, social, political and legal factors shaped by external institutions and policies.

These contextual factors are an important entry point for shaping and influencing agricultural systems (such as national policies, markets,

trade).


AN ASSETS-BASED MODEL FOR SUSTAINABILITYThe Modernisation of Agriculture

The process of agricultural modernisation during the 20th century has produced three distinct types of agriculture: industrialised, `Green Revolution’, and all that remains - the pre-modern, `traditional’ or `unimproved'. The first two types have

been able to respond to modern technological packages, producing highly productive systems of agriculture.


AN ASSETS-BASED MODEL FOR SUSTAINABILITYSustainable Agriculture

A more sustainable farming seeks to make the best use of nature’s goods and services whilst not damaging the environment. It does this by integrating natural

processes such as nutrient cycling, nitrogen fixation, soil regeneration and natural enemies of pests into food production processes. It also minimises the use of non-renewable inputs (pesticides and fertilizers) that damage the environment or harm

the health of farmers and consumers. It makes better use of the knowledge and skills of farmers, so improving their self-reliance. And it seeks to make

productive use of social capital - people’s capacities to work together to solve common management problems, such as pest, watershed, irrigation, forest and

credit management

High-yield polyculture

Organic fertilizers

Biological pest control

Integrated pestmanagement

Irrigation efficiency

Perennial crops

Crop rotation

Use of more water-efficient crops

Soil conservation

Subsidies for more sustainable farming

and fishing

Increase

Soil erosion

Soil salinization

Aquifer depletion

Overgrazing

Overfishing

Loss of biodiversity

Loss of primecropland

Food waste

Subsidies for unsustainable farming and fishing

Population growth

Poverty

Decrease

Sustainable Agriculture


Pangan minim limbahMengurangi konsumsi daging

Feed pets balanced grain foods instead of meat

Use organic farming to grow some of your food

Membeli bahan pangan organik

Komposting limbah makanan

Apa yang dapat dilakukan ?

Sustainable Agriculture


DEGRADASI LAHAN

KETAHANAN SUMBERDAYA ALAM

DAN PANGAN

smno.psdl.ppsub

DEGRADASI LAHAN PERTANIAN

Diunduh dari: http://andikks.blogspot.com/2012/06/degradasi-lahan_05.html……… 24/12/2012

DEGRADASI LAHAN

Degradasi lahan merupakan proses menurunnya kualitas dan kuantitas suatu lahan yang meliputi aspek

fisika tanah, kimia tanah, biologi tanah, pada suatu bidang lahan tertentu.

Dalam praktek budidaya pertanian sendiri sering akan menimbulkan dampak pada degradasi lahan. Dua faktor penting dalam usaha pertanian

yang potensial menimbulkan dampak pada sumberdaya lahan, yaitu tanaman dan manusia (sosio kultural) yang menjalankan pertanian.

Faktor AKTIVITAS manusia dapat memberikan dampak positip atau negatip pada suatu lahan, tergantung pada aktivitas pengelolaan

pertanian yang dilakukan. Apabila dalam menjalankan pertaniannya benar maka akan berdampak positip, namun apabila cara menjalankan pertaniannya salah maka akan

berdampak negatif.

Kegiatan budidaya pertanian yang menimbulkan dampak antara lain meliputi kegiatan pengolahan tanah, penggunaan sarana produksi yang tidak ramah lingkungan (pupuk dan insektisida) serta sistem budidaya

termasuk pola tanam yang mereka gunakan.

Tiga faktor penyebab degradasi tanah akibat campur tangan manusia secara langsung, yaitu : pertanian intensif, pembukaan tambang,

deforestasi. Faktor-faktor tersebut di Indonesia pada umumnya terjadi secara simultan, berikut adalah pembahasan dari ketiga degradasi pada

tiga bidang.

DEGRADASI LAHANDEGRADASI LAHAN PERTANIAN

Aktivitas budidaya pertanian dapat menyebabkan dampak negatif pada sumberdaya lahan.

Erosi dan pencemaran tanah terjadi akibat budi daya pertanian yang melampaui daya dukung tanah. Penggunaan bahan-bahan agrokimia

yang berlebihan dapat mencemari lingkungan dan mengganggu kelestarian kualitas tanah. Cara-cara budi daya pertanian yang tidak mengindahkan kaidahkaidah konservasi lahan menyebabkan kualitas lahan menurun sejalan dengan hilangnya lapisan tanah subur akibat

erosi dan pencucian hara.

Kegiatan pembangunan yang berpotensi menimbulkan dampak terhadap degradasi lahan antara lain kegiatan deforesterisasi, industri,

pertambangan, perumahan, dan kegiatan pertanian sendiri. Apabila kegiatan tersebut tidak dikelola dengan baik, maka akan mengakibatkan

terjadinya degradasi lahan pertanian yang mengancam keberlanjutan uasaha tani dan ketahanan pangan. Oleh karenanya, dalam kegiatan pembangunan hendaknya harus dipikirkan keberlanjutannya dimasa

mendatang (sustainabilitas).

Praktek budidaya pertanian sering mengakibatkan degradasi lahan. Kegiatan budidaya pertanian yang menimbulkan dampak negatif antara lain meliputi kegiatan pengolahan tanah, penggunaan sarana produksi

yang tidak ramah lingkungan (pupuk dan pestisida), serta sistem budidaya termasuk pola tanam yang tidak tepat.

Diunduh dari: http://andikks.blogspot.com/2012/06/degradasi-lahan_05.html……… 24/12/2012

Diunduh dari: http://pinterdw.blogspot.com/2012/06/penyebab-degradasi-lahan.html……… 24/12/2012

DEGRADASI LAHANBarrow (1991) merinci faktor-faktor utama penyebab degradasi

lahan :1) Bahaya alami2) Perubahan jumlah populasi manusia3) Marjinalisasi tanah4) Kemiskinan5) Status kepemilikan tanah6) Ketidakstabilan politik dan masalah administrasi7) Kondisi sosial ekonomi8) Masalah kesehatan9) Praktek pertanian yang tidak tepat, dan10) Aktifitas pertambangan dan industri.

Degradasi lahan ada tiga aspek, yaitu : aspek fisik. kimia dan biologi.

1. Degradasi fisik terdiri dari pemadatan, pengerakan, ketidakseimbangan air, terhalangnya aerasi, aliran permukaan, dan erosi.

2. Degradasi kimiawi terdiri dari asidifikasi, pengurasan unsur hara, pencucian, ketidakseimbangan unsur hara dan keracunan, salinisasi, dan alkalinisasi.

3. Degradasi biologis meliputi penurunan karbon organik tanah, penurunan keanekaragaman hayati tanah, dan penurunan karbon biomas.

Diunduh dari: http://www.ehow.com/list_6523052_types-soil-degradation.html……… 24/12/2012

DEGRADASI LAHANTYPES OF SOIL DEGRADATION

Soil degradation is any type of problem that removes soil in an area or makes high-quality soil become poor. Careless

agricultural practices, pollution and deforestation cause lots of soil degradation in the world. Several types of soil degradation

exist and are a threat to natural forests and planted crops.

Read more: Types of Soil Degradation | eHow.com http://www.ehow.com/list_6523052_types-soil-degradation.html#ixzz2FuczEfSE

SOIL EROSIONErosion occurs when the

topsoil that many plants need to grow gets blown or washed

away. While some erosion is natural,

the humans often remove plants that cover soil and,

therefore, speed up erosion. Since topsoil takes so long to build back up through natural processes, erosion damage is

almost irreversible.

NUTRIENT LOSSNutrient loss often occurs in

conjunction with salinization. The nutrient loss occurs through a variety of mechanisms, including

leaching, erosion, runoff, crop uptake and denitrification.

The crops uptake too many soil nutrients that farmers do not always

replace. Deforestation and careless

agricultural processes lead to soil degradation in the form of nutrient

loss. After soil becomes nutrient-poor,

crops and naturally occurring plants have a hard time growing in the area.

http://www.ehow.com/list_6523052_types-soil-degradation.html

http://www.ehow.com/list_6523052_types-soil-degradation.html

Diunduh dari: http://www.acsgarden.com/articles/other-gardening/soil-degradation.aspx……… 24/12/2012

DEGRADASI LAHAN

SOIL DEGRADATIONWhen plants (trees & shrubs) are cleared from a site, soil is exposed to

sunlight and the eroding effects of wind and water. Soil aeration is increased and the rate of weathering increases.

Apart from erosion, the proportion of organic matter in the soil gradually decreases, through the action of microbes in the soil which use

it as a source of energy ‑ unless the new land use provides some replacement.

TYPES OF SOIL DEGRADATION

A number of major soil related problems occur in Australia these include:

1. Kehilangan kesuburan tanah2. Erosi Tanah3. Salinitas4. Pemadatan Tanah5. Pengasaman Tanah6. Pencemaran tanah oleh bahan kimia

berbahaya.

Diunduh dari: http://www.fertilizer101.org/science/?seq=7 ……… 24/12/2012

HILANGNYA KESUBURAN TANAHKESUBURAN TANAH

Land use, human nutrition and the carbon cycle form an intricate set of relationships. Healthy plants use carbon dioxide, give off

oxygen and increase soil organic matter (OM), thereby enhancing soil fertility. Practices that increase organic matter can increase soil fertility while decreasing greenhouse gas emissions.

Diunduh dari: http://www.tankonyvtar.hu/hu/tartalom/tamop425/0010_1A_Book_angol_02_tapanyagg

azdalkodas/ch05.html ……… 24/12/2012

HILANGNYA KESUBURAN TANAHBASIC PLANT NUTRIENT CYCLE

The basic nutrient cycle usually describes the outstanding role of soil organic matter. Cycling of many plant nutrients, especially N, P, S, and micronutrients, are similar to the Carbon Cycle. Plant residues, grain

green manure, farmyard manure and other substances are returned to the soil. This organic matter pool of carbon compounds serve as food for

bacteria, fungi, and other decomposers. As organic matter is decomposed to simpler compounds, plant nutrients are released in available forms for root uptake and the cycle begins again. Plant-

available macronutrients such as N, P, K, Ca, Mg, S and micronutrients are also released when soil minerals dissolve.

Diunduh dari: http://www.ipm.iastate.edu/ipm/icm/2007/5-14/nitrogenloss.html ……… 24/12/2012

HILANGNYA KESUBURAN TANAHPOTENTIAL FOR N LOSSES

Greater losses occur when soils enter the spring season with recharged subsoil moisture, when more N is in the nitrate form, and when soils are warm. Deciding

if losses are substantial enough to warrant supplemental N application must therefore take into consideration the following factors: (1) amount of nitrate present, which is affected by time of N application, form of N applied, rate

applied, and use of a nitrification inhibitor; (2) when and the length of time soils are saturated; (3) subsoil recharge, leaching rate, and drainage--water amount

moved through the soil; and (4) loss of crop yield potential from water damage.

http://www.ipm.iastate.edu/ipm/icm/node/195

Diunduh dari: http://www.fao.org/docrep/010/ag120e/AG120E10.htm ……… 24/12/2012

HILANGNYA KESUBURAN TANAHIntegrated plant nutrient components in the Nepalese

farming system

An integrated nutrient model developed quite some time ago as shown below was a successful programme but it has not been popularized or has not been well adopted by large number of farmers. There should be a follow up study to see the impact on soil fertility management and to

look on how best we can promote to wider areas.

http://www.tankonyvtar.hu/hu/tartalom/tamop425/0010_1A_Book_angol_02_tapanyaggazdalkodas/ch05.html

HILANGNYA KESUBURAN TANAH

KEHILANGAN HARA DARI TANAH

There are several losses from soil nutrient pools caused by either unfavorable soil conditions or improper use of fertilizers. The main characteristics of these losses

are the following:Losses will result in a decrease in the amounts of plant available soil nutrients

Nutrient losses occur by:1. Releases from the soil - leaving the soil-plant system2. Transformation of soil nutrients into non-available forms (i.e. precipitation,

chemical reactions resulting insoluble forms etc.) = „internal losses”

PELEPASAN HARA DARI TANAH3. Crop removal by yields4. Erosion losses – nutrients in soil particles removed from soil by water5. Runoff – loss of dissolved nutrients moving across the soil profile6. Leaching– moving dissolved nutrient forms downward into the groundwater7. Gaseous losses to the atmosphere by volatilization and denitrification.

Under various cropping systems, both internal and external losses of nutrients from soils may be rather diverse.

„INTERNAL LOSSES”

8. Transformation of soil nutrients into non-available forms (i.e. precipitation, chemical reactions resulting insoluble forms etc.)

9. Transformation into insoluble forms – typical for P Strong fixation in interlayer sites of clay minerals – ammonium and K+ ions

10. These forms do not leave the soil = therefore referred as „internal losses”

Diunduh dari: http://www.examiner.com/article/permaculture-from-a-to-z-fertility-of-the-soil ……… 24/12/2012

HILANGNYA KESUBURAN TANAHWhat happens if we lose soil fertility, we will eventually cease to exist

as soil is alive and we require soil for almost all of the food that we grow today around the world.

The healthy soil contains:1. It has sufficient concentrations of nitrogen, phosphorous, and potash

(potassium) to support plant life.2. It also has sufficient levels of the trace minerals needed for plant

nutrition, including boron, chlorine, cobalt, copper, iron, manganese, magnesium, molybdenum, sulfur, and zinc.

Diunduh dari: http://www.cep.unep.org/pubs/Techreports/tr41en/section3.html……… 24/12/2012

EROSI TANAH Soil erosion is a natural process characterized by the transport or displacement of particles (sediment) that are detached by rainfall,

flowing water, or wind. Soil erosion can be caused by the improper use of lands for cultivation or grazing and by deforestation.

The types of soil erosion associated with agricultural activities are :1. Splash erosion, which occurs when rain hits exposed soils. 2. Sheet and rill erosion, which mainly moves soil particles from the surface or

plough layer of the soil. Surface sediments typically contain higher pollution potential due to richer nutrient content, the presence of chemicals from past fertilizer and pesticide applications, and natural biological activities.

3. Rill and gully erosion, severe erosion in which trenches are cut to a depth greater than 1 foot. Generally, trenches too deep to be crossed by farm equipment are considered gullies (USEPA, 1994).

4. Stream and channel erosion, which occurs due to increased rates and volumes of runoff from agricultural land uses flowing through a stream or channel.

Diunduh dari: http://www.earthonlinemedia.com/ebooks/tpe_3e/soil_systems/soil__development_soil_

forming_factors.html……… 24/12/2012

EROSI TANAHEffect on soil erosion

Slope angle and length affects runoff generated when rain falls to the surface. Examine the diagram below showing the relationship between hill slope position,

runoff, and erosion.The amount of water on a particular hill slope segment is dependent on what falls from precipitation and what runs into it from an upslope hill slope segment. The hill slope has been divided into several segments and the amount of precipitation falling on each segment is the same. As water runs down slope, the water that has

accumulated in segment A runs off adding to what falls into segment B by precipitation. The water in B runs into C, and C into D, and so on. The amount of water increases in the down slope direction as water is contributed of water from upslope segments. The velocity of the water increases as well as it moves towards the base of the slope. As a result, the amount and velocity of water, and hence rate

of erosion increases as you near the base of the slope.

Diunduh dari: http://www.ecy.wa.gov/programs/wq/wqguide/erode.html……… 24/12/2012

EROSI TANAHPENGENDALIAN EROSI

Soil erosion occurs naturally when rain falls. Runoff flows to the lowest point of the landscape. The velocity depends on the characteristics of the

soils, the slope of the land and the vegetative cover. Erosion can be a serious environmental problem when the land is

disturbed by development, agriculture, or forestry. Surfaces like roads, roofs, driveways and hard-packed soils will not absorb water, and the runoff increases. Expanses of pavement like parking lots reduce the

chances for ground water recharge. Exposed soils are lost and the land becomes less productive. Fertilizers and pesticides that may have been

applied wash away, too, causing water quality problems for people living downstream.

Diunduh dari: ……… 24/12/2012

EROSI TANAHEROSION EFFECTS ON SOIL WATER STORAGE, PLANT

WATER UPTAKE, AND CORN GROWTHB. J. Andraski and B. Lowery

SSSAJ. 1992. Vol. 56 No. 6, p. 1911-1919

Levels of past erosion were based on depth to red clay (2Bt horizon): slight, 0.95 m; moderate, 0.74 m; and severe, 0.45 m. The total quantity of plant-extractable water that could be stored in the upper 1 m of slightly eroded soil (181 mm) was 7% more than that for moderately eroded soil (169 mm) and 14% more than that

for severely eroded soil (159 mm). For all erosion levels, water retained in the 0.5- to 1.0-m soil depth was utilized

by corn. Erosion level had no negative effect on early-season plant growth. As plant-

extractable water decreased to <55 to 60% of total, evapotranspiration (ET) and vegetative-growth rates decreased as erosion level increased. The greatest

differences in ET rates among erosion levels were observed during a 35-d period in the drought year of 1988 when rates averaged 3.7 mm d−1 for slight erosion, 2.6

mm d−1 for moderate erosion, and 2.2 mm d−1 for severe erosion.

For the 3 yr in which plant water stress was observed, maximum plant heights for the slight erosion level averaged 7% more than those for moderate erosion and

13% more than those for severe erosion.

Although the soil's capacity to store and supply water decreased as erosion increased, the observed effects of erosion level on grain and stover yields, grain-

yield components, and harvest populations typically were not significant.

Diunduh dari: https://www.soils.org/publications/sssaj/abstracts/76/5/1789……… 24/12/2012

EROSI TANAH. CROPPING AND TILLAGE SYSTEMS EFFECTS ON SOIL EROSION

UNDER CLIMATE CHANGE IN OKLAHOMAX.-C.(John) Zhang

SSSAJ. 2012. Vol. 76 No. 5, p. 1789-1797

Soil erosion under future climate change is very likely to increase because of increases in occurrence of heavy storms.

The objective of this study is to quantify the effects of common cropping and tillage systems on soil erosion and surface runoff during 2010 to 2039 in central

Oklahoma. A combination of 18 cropping and tillage systems is evaluated using the Water

Erosion Prediction Project (WEPP) model for 12 climate change scenarios projected by four global climate models (GCMs) under three emissions scenarios.

Tillage systems include conventional, reduced, delayedno tillage. Cropping systems include continuous monocultures of winter wheat, soybean,

sorghumcotton and double crops of wheat and soybeans. Compared with the present climate, overall t tests show that the future mean

precipitation will decrease by some 6% (>98.5% probability), daily precipitation variance increase by 12% (>99%), and mean temperature increase by 1.36°C

(>99%).

Despite the projected precipitation declines, the overall averaged runoff and soil loss will increase by 19.5 and 43.5% because of increased occurrence of large

storms. Soil erosion is positively related to the degree of tillage disturbances in all

cropping systems. Compared with the conventional till, reduced, delayedno tillage substantially reduce soil erosion, showing that adoption of conservation

tillage will be effective in controlling soil erosion in the next 30 yr. Cropping systems decrease runoff and soil loss from continuous cotton

to soybean to sorghum to wheat in all tillage systems under climate change, indicating a preference of winter wheat for controlling runoff

and soil loss in the region.

Diunduh dari: https://www.agronomy.org/publications/sssaj/abstracts/56/3/SS0560030878 ………

24/12/2012

DEGRADASI LAHAN. SOIL EROSION EFFECTS ON CORN YIELDS ASSESSED BY

POTENTIAL YIELD INDEX MODELE. M. Craft , R. M. Cruse and G. A. Miller

SSSAJ. 1992. Vol. 56 No. 3, p. 878-883

Soil erosion alters crop production via alteration of the soil chemical and physical environment.

The objectives of this study were to: (i) develop a Potential Yield Index (PYI) model to index soil productivity based on simulated root growth, soil properties, and potential nutrient and water uptake of corn (Zea mays L.) through a growing

season, (ii) utilize the PYI to estimate erosion effects on soil productivity by simulating the removal of 15 and 30 cm of soil, and (iii) simulate the impact of

fertilizer additions to the eroded soil on the PYI.

The PYI model independently estimates P, K, and water (W) uptake by corn. From these estimates, three separate yield indexes (PYIP, PYIK, and PYIW) are

calculated. The lowest yield index is identified as the PYI for a given soil.

The predicted PYIs for 45 soils in Iowa compared well to the 1984 10-yr average corn yield (R2 = 0.83) and corn suitability rating (R2 = 0.73) for each soil.

Changes in the PYI were predicted for 15 and 30 cm of simulated erosion. After 15-cm soil loss, the PYI for all soils decreased, with all but three soils remaining within 15% of the uneroded PYI. The PYI decreased further after 30-cm soil loss,

with only 12 soils remaining within 15% of the uneroded PYI.

Fertilizer additions to the plow layer of the eroded soils were then simulated. The PYI returned to within 5% of the uneroded PYI for 38 soils with 15-cm soil loss

and for 27 soils with 30-cm soil loss.

The PYI indicated that the soil factor that most limited plant yield changed with the soil, amount of soil loss, and plow-layer soil fertility status.

Diunduh dari: http://www.geotek.lipi.go.id/riset/index.php/jurnal/article/view/28 ……… 25/12/2012

EROSI TANAHPERKIRAAN TINGKAT EROSI TANAH DI SUB DAS

BESAI, LAMPUNG BARATAsep Mulyono

Jurnal Riset Geologi dan Pertambangan, Vol 19, No 1 (2009)

Tingkat erosi tanah di sub DAS Besai telah diperkirakan sebagai dasar kuantitatif dalam merekomendasikan upaya mempertahankan, memulihkan, meningkatkan

kesuburan dan fungsi tanah sebagai pengatur tata air. Perkiraan tingkat erosi tanah dilakukan dengan metoda RUSLE yang dilakukan secara spasial dengan menggunakan perangkat lunak Sistem informasi geografis

(SIG). Erosivitas, erodibilitas, kemiringan lereng, panjang lereng, sistem penanaman dan faktor konservasi merupakan 6 parameter data yang dimasukan

dalam pendekatan RUSLE.

Tingkat konversi lahan, khususnya hutan lindung menjadi lahan pertanian dan perkebunan, sangat pesat terjadi di Sub DAS Besai. Sub DAS Besai yang terletak di wilayah Kecamatan Sumber Jaya, Kabupaten Lampung Barat merupakan salah satu bagian hulu DAS Tulang Bawang Lampung. Selama rentang waktu 30 tahun

(1970 – 2000) telah terjadi penurunan tutupan lahan hutan sebesar 48 %. Perubahan terjadi sebagai akibat tingginya aktivitas masyarakat dalam usaha tani

kopi monokultur dan tanaman semusim.

Hasil studi menunjukkan 23.62% wilayah penelitian dikategorikan dalam tingkat erosi tanah yang normal, tingkat ringan seluas 42.98%, tingkat moderat seluas

14.57%, tingkat berat seluas 15.38% dan sangat berat seluas 3.45%. Seluas 45% wilayah dengan tutupan lahan perkebunan kopi mengalami tingkat erosi dalam kategori ringan sampai sangat berat pada semua rentang kelerengan dan jenis

tanah. Perkebunan kopi sistem monokultur mengakibatkan lapisan tanah sangat mudah

tergerus oleh adanya aliran permukaan dikarenakan tidak adanya tutupan tanah di bawah kanopi tanaman kopi tersebut.

Diunduh dari: staff.uny.ac.id/..../artikel_sediment%20yield_sainte... ……… 25/12/2012

EROSI TANAHEVALUASI SEDIMENT YIELD DI DAERAH ALIRAN SUNGAI

CISANGGARUNG BAGIAN HULU DALAM MEMPERKIRAKAN SISA

UMUR WADUK DARMAMuhammad Nursa’ban.

Hasil Penelitian Dosen muda tahun 2006, Dosen Jurusan Pendidikan Geografi UNY.

Hasil penelitian menunjukan bahwa tingkat erosi tanah permukaan yaitu 31.558,74 ton/tahun, atau rata-rata 573,795 ton/ha/tahun, erosi total 39.448,43 ton/tahun atau 717,244 ton/ha/tahun dan erosi tanah yang

diperbolehkan yaitu 686,033 ton/tahun atau sekitar 12,473 ton/ha/tahun.

Data-data tersebut menunjukkan bahwa tingkat erosi permukaan maupun erosi total berlangsung cukup tinggi dibandingkan dengan besar

erosi yang diperbolehkan.

Sediment Yield tahunan di Waduk Darma yaitu 32.996,419 ton/tahun atau 14.873,660 m3.

Waduk Darma tidak dapat berfungsi lagi yaitu pada saat mencapai umur ± 84,25 tahun. Tahun 2006 Waduk Darma telah beroperasi selama 36

tahun sehingga sisa umur Waduk Darma sampai terpenuhinya tampungan mati oleh sedimen yaitu ± 48,25 tahun atau tampungan mati

akan terisi penuh yaitu pada tahun ± 2054.

Diunduh dari: www.limnologi.lipi.go.id/.../makalah.php?... ……… 25/12/2012

EROSI TANAH

PREDIKSI BEBAN NUTRIEN DAN SEDIMEN DAS SUMPUR DANAU SINGKARAK MENGGUNAKAN

MODEL AGNPSTuahta Tarigan dan Iwan Ridwansyah.

LIMNOTEK, 2005, Vol, XII, No, 2, p. 34-40

AGNPS merupakan sebuah program model untuk mensimulasikan kualitas air dan sedimen dari suatu catchment yang didominasi lahan

pertanian. Model ini dikombinasikan dengan perangkat program GIS untuk

memperkirakan kemungkinan penambahan fospor ke DAS Sumpur,

Paket Program GIS (ArcView 3.1, 3D Analyst, Spatial Analyst) digunakan untuk mempersiapkan input data model dan proses

penempatan dari hasil simulasi.

Perkiraan dari loading nutrient dari Sungai Sumpur yang masuk ke Danau Singkarak memperlihatkan nilai 1.875 ton tahun-1 sedimen, 52,5

ton tahun-1 Total N dan 37,5 ton tahun-1 Total P dan 195 ton tahun-1 COD.

Diunduh dari: http://digilib.litbang.deptan.go.id/repository/repository/artikel/26/4/2004/0/1472 ……… 25/12/2012

EROSI TANAHMODIFIKASI FAKTOR C-USLE DALAM MODEL ANSWERS

UNTUK MEMPREDIKSI EROSI DI DAERAH TROPIKA BASAH (STUDI KASUS: DAS NOPU HULU, SULAWESI TENGAH)

Y. Hidayat, N. Sinukaban, H. Pawitan, dan K. MurtilaksonoJurnal Tanah dan Iklim. Vol.26 No.4 Th. 2004

Penelitian dilakukan untuk : a) mendefinisikan nilai faktor pengelolaan tanaman sebagai parameter input model ANSWERS, b) membangun model ANSWERS

dalam PCRaster untuk mensimulasikan perubahan penggunaan lahan dan penerapan teknik konservasi tanah dan air, dan c) mengkaji dampak konversi

hutan terhadap aliran permukaan, erosi dan kehilangan hara. Aliran permukaan dan erosi harian diukur pada lahan hutan primer, hutan

sekunder, lahan terbuka, jagung, kakao muda, kakao sedang, kakao dewasa, dan tumpang sari antara kakao muda dengan jagung, pisang dan ketela pohon. Pada

outlet daerah aliran sungai debit aliran ditentukan melalui pengukuran tinggi muka air dan kecepatan aliran, sedangkan volume sedimen diukur melalui

pengambilan sampel sedimen.

Penggunaan faktor pengelolaan tanaman parsial pada model ANSWERS dan ANSWERS-PCRaster memberikan hasil prediksi erosi lebih baik dibandingkan

dengan menggunakan faktor pengelolaan tanaman USLE (faktor C-USLE), khususnya pada curah hujan tinggi.

Penghutanan kembali lahan berlereng curam (> 45%) yang diikuti oleh penerapan teras gulud pada lahan pertanian merupakan tindakan pengelolaan terbaik dalam

mengendalikan aliran permukaan dan erosi untuk menjamin pertanian berkelanjutan dan keberlanjutan fungsi daerah aliran sungai.

Konversi hutan ke lahan pertanian telah meningkatkan aliran

permukaan, erosi dan kehilangan hara.

Diunduh dari: jatim.litbang.deptan.go.id/.../index.php?... ……… 25/12/2012

EROSI TANAH. DEGRADASI TANAH DI LAHAN KERING WILAYAH

BARITO KALIMANTAN TENGAHM. A. Firmansyah, R.Y. Galingging dan Suparman (Balai Pengkajian Teknologi Pertanian

Kalimantan Tengah)A. Krismawati (Balai Pengkajian Teknologi Pertanian Jawa Timur)

Degradasi tanah di Indonesia umumnya terjadi di lahan kering yang dipicuoleh erosi tanah dan salah kelola tanah.

Tujuan tulisan ini untuk menunjukkan besarnya erosi yang terjadi pada berbagai sistem usahatani eksisting antara lain: padi gogo, jagung, kacang tanah, ubi kayu,

dan karet rakyat. Lokasi penelitian dilaksanakan di Lagan (kemiringan 6%) di Kabupaten Barito Timur dan Jingah (kemiringan 16%) di Kabupaten Barito

Utara. Hasil analisis menunjukkan bahwa Jingah mengalami erosi lebih besar dibandingkan Lagan, hal ini disebabkan oleh tingginya faktor erosivitas hujan,

kemiringan lereng, dan teknik konservasi tanah yang buruk.

Erosi potensial di Jingah mencapai 1.497 t/ha/th sedangkan di Lagan mencapai 431 t/ha/th. Kondisi tersebut menyebabkan kedua lokasi tergolong memiliki Indeks Bahaya Erosi (IBE) ekstrem, dengan nilai 47,4 untuk Jingah dan 11,2

untuk Lagan. Erosi aktual pada sistem usahatani di Jingah tertinggi pada karet rakyat mencapai 954 t/ha/th (91 mm/th), begitu juga di Lagan mencapai 183

t/ha/th (14 mm/th). Erosi aktual terendah pada sistem usahatani kacang tanah, di Jingah mencapai

505 t/ha/t (48 mm/th) dan di Lagan mencapai 97 t/ha/th (8 mm/th).

Erosi yang terjadi dikedua lokasi jauh melampaui Eosi yang piperbolehkan (EDP) yang hanya mencapai 3 mm/th. Erosi yang terjadi berdampak terhadap

kehilangan produktivitas cukup besar di Jingah yaitu 21% pada karet rakyat, dan terendah sebesar 2% di Lagan untuk padi gogo dan kacang tanah. Guna

mencegah erosi yang besar, maka dikedua lokasi perlu dilakukan perbaikan terutama pada pengelolaan teknik konservasi tanah.

http://digilib.litbang.deptan.go.id/repository/repository/publikasi/Jurnal/

Diunduh dari: balittanah.litbang.deptan.go.id/.../sutonocitarum08... ……… 25/12/2012

EROSI TANAHEROSI PADA BERBAGAI PENGGUNAAN LAHAN DI

DAS CITARUMS. Sutono, S. H. Tala’ohu, O. Sopandi, dan F. Agus

Balai Penelitian Tanah, BogorProsiding Seminar Nasional Multifungsi dan Konversi Lahan Pertanian

Lahan sawah mempunyai banyak fungsi, termasuk diantaranya fungsi produksi, dan lingkungan.

Penelitian bertujuan untuk menduga besarnya erosi pada lahan pertanian di daerah aliran sungai Citarum serta menduga besarnya biaya pengganti

(replacement cost method/RCM) pengamanan erosi jika luas lahan sawah berkurang. Pendugaan erosi menggunakan metode universal soil loss equation

(USLE).

Hasil penelitian menunjukkan bahwa erosi pada lahan sawah lebih rendah dibandingkan dengan tegalan, kebun campuran, kebun teh, kebun karet, dan

hampir sama dengan tingkat erosi hutan.

Erosi paling tinggi terjadi pada lahan tegalan. Lahan sawah erosinya berkisar antara 0,33 t/ha/tahun dan 1,45 t/ha/tahun.

Seluruh replacement cost untuk Citarum pada tahun 2000 sebesar Rp. 18,6 milyar. Jumlah ini adalah perkiraan investasi yang harus dikorbankan untuk

penanganan sedimen apabila sawah yang ada sekarang di Citarum mengalami konversi.

Diunduh dari: balittanah.litbang.deptan.go.id/.../kundarto17.pdf……… 25/12/2012

EROSI TANAHNERACA AIR, EROSI TANAH DAN TRANSPOR LATERAL

HARA NPK PADA SISTEM PERSAWAHAN DI SUB DAS KALI BABON, SEMARANG

Muhamad Kundarto 1, F. Agus 2, Azwar Maas 3, dan B. H. Sunarminto 3Jurusan Ilmu Tanah UPN “Veteran” Yogyakarta, 2 Balai Penelitian Tanah Bogor, 3 Jurusan

Tanah UGM YogyakartaProsiding Seminar Nasional Air, Erosi Tanah Konversi Lahan Pertanian

Penelitian ini bertujuan untuk mengetahui neraca air, erosi tanah, dan transpor lateral hara NPK pada sistem persawahan. Penelitian dilaksanakan selama dua musim tanam dari Oktober 2001 sampai Juni 2002 di sub daerah aliran sungai Kali Babon, Semarang.

Hasil penelitian pada musim ke dua menunjukkan total input air sebesar 4031,81 mm yang berasal dari air irigasi 3530,41 mm dan air hujan 501,40 mm. Total output air sebesar

3035,13 mm terdiri atas air drainase 153,22 mm, infiltrasi/perkolasi 94,74 mm, evapotranspirasi 85,87 mm, dan genangan 2701,30 mm. Selisih antara input dan output air

sejumlah 996,68 mm diduga merupakan total air yang menyusup secara lateral melalui pematang (seepage dan lubang tikus/ketam) dan air yang tersimpan pada lapisan olah.

Total tanah yang tererosi dari daerah atas (upland) dan masuk ke sawah pada musim sebesar 864,1 kg dan yang keluar (lewat outlet petak no. 18) sebesar 347,5 kg. Sehingga tanah yang

mengendap di petak sawah sebesar 516,6 kg (2,05 t/ha). Pada musim kedua, total tanah masuk ke sawah sebesar 1567,1 kg dan yang keluar dari sawah (lewat outlet petak 18)

sebesar 209,6 kg. Sehingga tanah yang mengendap di petak sawah sebesar 1357,5 kg (5,40 t/ha). Jumlah tanah yang mengendap pada musim kedua 2,5 kali lebih besar dibanding

musim pertama.

Total hara N, P, dan K dalam bentuk NH4+, NO3-PO43-, dan K+ yang terkandung dalam air irigasi dan masuk ke sawah masing-masing sebesar:

98; 478; 29; dan 237 g/ha/musim. Sedangkan total hara NH4+, NO3-, PO43-, dan K+ yang terkandung dalam air drainase dan keluar dari sawah

masing-masing sebesar: 10; 161; 413; dan 35 g/ha/musim. Penambahan hara NH4+, NO3-, dan K+ pada sawah masing-masing

sebesar: 88; 317; dan 203 g/ha/musim. Hara PO43- mengalami pengurangan sebesar 384 g/ha/musim.

Diunduh dari: jurnalpengairan.ub.ac.id/index.php/jtp/.../103 ……… 25/12/2012

EROSI TANAH. APLIKASI SISTEM INFORMASI GEOGRAFIS (SIG) UNTUK

IDENTIFIKASI LAHAN KRITIS dan ARAHAN FUNGSI LAHANDAERAH ALIRAN SUNGAI SAMPEAN

Runi Asmaranto, Ery Suhartanto dan Bias Angga PermanaJurusan Pengairan Fakultas Teknik Universitas Brawijaya

DAS Sampean merupakan daerah aliran sungai yang kondisi topografinya rata-rata sangat curam. Kondisi tata guna lahan yang sebagian besar sawah irigasi ini cukup memungkinkan terjadinya erosi. Apalagi tataguna lahan lainnya berupa ladang, semak dan sawah tadah hujan yang tanamannya merupakan tanaman

berkedalaman akar rendah dan berperan besar dalam proses penyebab terjadinya kerusakan tanah, mempercepat laju erosi dan meningkatkan volume limpasan

permukaan.Metode yang digunakan dalam menghitung besarnya laju erosi adalah metode

MUSLE dimana metode tersebut menggunakan pendekatan dari faktor limpasan permukaan. Pengolahan data-datanya menggunakan Sistem Informasi Geografis

(SIG) karena memudahkan dalam penganalisaan dan pengelompokan data.

Dari hasil analisa diperoleh debit limpasan permukaan yang terjadi sebesar 247,967 m3/ dt. Total Erosivitas Limpasan Permukaan yang

terjadi adalah 48.129,73 m2/jam, hal ini memicu terjadinya laju erosi yang rata-ratanya mencapai 43.939,94 ton/ha/thn, atau identik

dengan kehilangan tanah sebesar : 258,470 cm/thn.

Besarnya laju erosi pada DAS Sampean ini mengakibatkan tingkat bahaya erosi sebesar 95,54% dari luas wilayahnya termasuk sangat berat. Sedangkan untuk

tingkat bahaya erosi lainnya yaitu, berat : 2,72%, sedang : 1,02%, ringan : 0,72%.

Analisa kemampuan lahan didominasi kemampuan kelas VII (75,39%), yang merupakan daerah Pengembalaan Terbatas. Sedangkan ARLKT di DAS Sampean

terdiri dari 3 (tiga) kawasan, yaitu Kawasan lindung (10,53%), Kawasan Penyangga (52,23%), Kawasan Budidaya Tanaman Tahunan (37,23%).

Diunduh dari: repository.ung.ac.id/.../TINGKAT_EROSI_PERM... ……… 25/12/2012

EROSI TANAHTINGKAT EROSI PERMUKAAN PADA LAHAN PERTANIAN

JAGUNG DI DAS ALO-POHU PROVINSI GORONTALOFitryane Lihawa

Pusat Studi Lingkungan Universitas Negeri GorontaloPROSIDING KONFERENSI DAN SEMINAR NASIONAL PUSAT STUDI LINGKUNGAN HIDUP

INDONESIA KE 21. 13 – 15 SEPTEMBER 2012 DI MATARAM

Fenomena pemanfaatan lahan untuk pertanian semakin meningkat, terlebih lagi setelah dicanangkannya Program Agropolitan di Provinsi Gorontalo. Pada Tahun 2003 luas

pertanianlahan kering adalah 1.398 ha dan Tahun 2005 meningkat hingga 30.338 ha, dan pada Tahun2010 mencapai 150.020 ha (Citra Landsat Tahun 2003, Tahun 2005 dan BPS Tahun 2011).

Perubahan penggunaan lahan tersebut dapat mengakibatkan kerusakan DAS yang berdampak pada rusaknya fungsi hidroorologis DAS. Salah satu DAS penyumbang sedimen

terbesar keDanau Limboto adalah DAS Alo-Pohu.

Pengukuran erosi permukaan dilakukan dengan menggunakan sistem plot dengan bentuk persegi panjang. Ukuran petak yaitu lebar 2 m dan panjang 5 m dan ketinggian 20 cm di atas

permukaan tanah. Untuk mengkaji pengaruh curah hujan terhadap erosi permukaan pada lahan pertanian jagung digunakan analisis regresi.

Hasil pengukuran erosi permukaan pada lahan pertanian jagung dengan kemiringan lereng datar (3,5%) menunjukkan bahwa tingkat erosi

permukaan sebesar 1,04 ton/ha/tahun (sangat rendah), pada lereng landai tingkat erosi permukaan sebesar 9,88 ton/ha/tahun (sangat rendah), pada lereng agak curam tingkat erosi permukaan sebesar 40.588 ton/ha/tahun

(rendah), dan pada lereng curam tingkat erosi permukaan sebesar 176.490 ton/ha/tahun (sedang).

Hasil pengamatan selama satu tahun menunjukkan bahwa erosi permukaan akan berkurang seiring dengan umur pertumbuhan jagung. Hal ini disebabkan karena telah disertai dengan tumbuhnya tanaman bawah (rumput-rumputan) pada umur jagung memasuki bulan kedua

dan ketiga. Pengaruh curah hujan terhadap erosi permukaan pada lahan pertanian jagung lereng datar adalah Log Y = -3,2 + 3,11 Log X; pada lereng landai Log Y = -3,02 + 2,93 Log X; pada

lereng agak curam Log Y = -2,73 + 3,74 Log X; dan pada lereng curam Log Y = 0,28 + 1,71 Log X.

Diunduh dari: www.forda-mof.org/index.php/content/.../788……… 25/12/2012

EROSI TANAHANALISIS SPASIAL TINGKAT BAHAYA EROSI DI WILAYAH

DAS CISADANE KABUPATEN BOGORTuti Herawati (Pusat Litbang Hutan dan Konservasi Alam)

Jurnal Penelitian Hutan dan Konservasi Alam. Vol. VII No. 4 : 413-424, 2010

Penelitian ini bertujuan untuk menghitung tingkat bahaya erosi di DAS Cisadane berdasarkan rumus USLE menggunakan analisis GIS. Berdasarkan rumus yang digunakan, maka diperlukan empat jenis peta sebagai dasar perhitungan tingkat

bahaya erosi, yaitu peta curah hujan, peta jenis tanah, kemiringan, dan peta penutupan lahan. Pada setiap peta dilakukan klasifikasi menjadi empat atau lima kelas berdasarkan standar tertentu. Proses overlay dilakukan untuk mendapatkan

hasil akhir berupa tingkat bahaya erosi yang dikategorikan menjadi lima kelas yaitu sangat ringan, ringan, sedang, berat, dan sangat berat.

Hasil penelitian menunjukkan bahwa tingkat bahaya erosi di DAS Cisadane meliputi sangat ringan hingga sangat berat dengan

persentase luas lahan berturut-turut dari yang sangat ringan hingga sangat berat 55,85%; 15,74%; 6,33%; 0,81%; dan 0,30%. Lahan

dengan tingkat bahaya erosi sangat berat meliputi luas 316 ha dan tingkat berat meliputi 851 ha.

Tamansari merupakan kecamatan yang memiliki luas wilayah dengan tingkat bahaya erosi sangat berat terluas yaitu 87 ha. Beberapa kecamatan lain yang

memiliki luas lahan dengan tingkat bahaya erosi berat adalah Tenjolaya, Caringain, Cijeruk, dan Nanggung.

Hasil penelitian ini dapat digunakan sebagai data dasar untuk membuat rencana pengeolaan DAS yang baik.

Diunduh dari: balittanah.litbang.deptan.go.id/.../hsuganda_sayura...……… 25/12/2012

EROSI TANAHPENGKAJIAN PENERAPAN TEKNIK KONSERVASI TANAH

PADA LAHAN USAHATANI BERBASIS TANAMAN SAYURAN DI SENTRA TEMBAKAU

H. Suganda dan Ai DariahPengkajian Penerapan Teknik Konservasi Tanah

BALITTANAH – LITBANG - DEPTAN.

Studi ini bertujuan untuk mendapatkan informasi tentang penerapan teknik konservasi tanah dalam usahatani sayuran di daerah sentra tembakau, Kabupaten Temanggung. Penelitian dilaksanakan tepatnya di tengah lokasi demontrasi plot

penerapan teknologi konservasi tanah dengan luas lahan 2,85 ha di Desa Batursari dengan 13 orang petani kooperator, dan 2,53 ha di Desa Kledung

dengan 10 orang petani kooperator. Pengamatan berlangsung mulai musim hujan (MH) 2006/07 sampai dengan MH 2007/08. Tanah di dua lokasi tersebut

tergolong Andisol. Teknik konservasi tanah yang diterapkan adalah cara mekanik dengan tambahan rumput penguat teras.

Hasil penelitian menunjukkan bahwa dengan menerapkan teknik konservasi tanah ternyata erosi pada lahan sayuran di sentra

tembakau dapat diturunkan sebanyak 38,4 % - 66,2 %, bahkan kehilangan tanah akibat erosi dapat ditekan menjadi < 6,0 t/ha.

Rumput penguat teras (paspah) dengan luasan 1 m2, dapat menghasilkan hijauan 3,6-4,0 kg, cukup untuk kebutuhan sehari

pakan domba yang bobotnya sekitar 20 kg.

Penerapan konservasi tanah dapat mengurangi laju kehilangan hara akibat erosi dan mempertahankan kesuburan tanah. Petani kooperator di Desa Kledung yang

sudah menerapkan teknik konservasi tanah, lahannya relatif lebih subur dibanding dengan lahan petani kooperator di Desa Batursari, sehingga rata-rata

pendapatannya per tahun lebih tinggi dari Rp. 3.100.000 .

Diunduh dari: http://padangekspres.co.id/?news=berita&id=8183 ……… 25/12/2012

ANCAMAN KEKERINGANSAWAH KERING, WARGA SHALAT ISTISQO’

Petani Nagari Canduang Koto Laweh was-was jika musim kemarau terus berlanjut hingga sebulan ke depan. Irigasi yang berada di nagari itu tidak lagi mampu mengalirkan air ke lahan pertanian. Sebab debit air semakin berkurang

sejak kemarau bulan lalu. Menanggapi persoalan yang terjadi, pemerintah nagari menganjurkan masyarakat untuk melaksanakan shalat minta hujan (istisqo’).

”Semoga hujan yang turun bisa menjadikan tanaman kami bisa kembali tumbuh subur,” harap Wan saat berbincang dengan Padang Ekspres di salah satu warung

kopi di Jorong Tigo Alua Nagari Koto Laweh.

Diunduh dari: http://www.metrotvnews.com/read/news/2012/08/08/101462/8.950-Hektare-Sawah-di-Lebak-Kekeringan/6……… 25/12/2012

ANCAMAN KEKERINGAN. 8.950 HEKTARE SAWAH DI LEBAK KEKERINGAN

Rabu, 8 Agustus 2012 20:20 WIBMetrotvnews.com, Lebak:

Kekeringan sawah di Kabupaten Lebak, Provinsi Banten, hingga saat ini mencapai 8.950 hektare akibat kemarau yang terjadi belakangan ini.

"Kekeringan ini tentu berdampak terhadap berkurangnya produksi pangan“.Ia mengatakan pihaknya terus melakukan penyelamatan tanaman padi yang

mengalami kekeringan dengan pengoptimalan pompanisasi terpadu.Diperkirakan dari 8.950 hektare itu dipastikan seluas 4.650 hektare bisa

diselamatkan dengan pengairan menggunakan pompanisasi terpadu. Sedangkan 4.300 hektare terancam gagal panen.

Sebagian besar areal persawahan yang terjadi kekeringan itu di daerah sawah tadah hujan. Sawah tadah hujan itu disebabkan tidak memiliki saluran irigasi

yang memadai. Akibat kekeringan ini, petani mengalami kerugian hingga miliaran rupiah apabila tanaman padi mereka gagal panen. Saat ini, biaya

produksi rata-rata Rp5 juta per hektare.

Diunduh dari: http://bisnis-jabar.com/index.php/berita/450-ha-sawah-di-indramayu-terancam-kekeringan……… 25/12/2012

ANCAMAN KEKERINGANANTARA. 20 Juni 2011 | 14:10 WIB

450 Ha sawah di Indramayu terancam kekeringan

INDRAMAYU: Sekitar 450 hektare sawah di Desa Soge, Indramayu, Jawa Barat, terancam gagal panen akibat kekeringan.

Pasokan air memasuki musim kemarau semakin sulit dan diperkirakan ratusan hektare sawah akan terancam gagal panen akibat kekeringan. Dua sungai

pemasok air, yaitu kali Prawan dan Kali Persijat, debitnya semakin menurun. Jika hujan tidak turun, diperkirakan tanaman milik petani setempat yang baru berusia

kurang dari dua bulan akan kering akibat pasokan air terhambat.Petani kurang memperhatikan cuaca. Mereka terlalu memaksakan tanam padi,

padahal mulai memasuki kemarau. Musim tanam tahun sebelumnya pasokan air cukup melimpah, sehingga mereka terlena diperkirakan hujan masih panjang.

Menurut dia, petani di daerah pantura Indramayu harus tanggap memperkirakan pasokan air hujan karena lahan pertanian masih mengandalkan tadah hujan.

Lahan pertanian di sepanjang pantai pesisir utara Indramayu memasuki kemarau setiap tahun mengalami kekeringan, sementara musim hujan sawah sering

terendam akibat banjir..

Diunduh dari: http://bisnis-jabar.com/index.php/berita/48-000-hektare-sawah-di-kabupaten-bekasi-kekeringan ……… 25/12/2012

ANCAMAN KEKERINGAN ANTARA. 12 September 2011 | 19:51 WIB

48.000 HEKTARE SAWAH DI KABUPATEN BEKASI KEKERINGAN

BEKASI (bisnis-jabar.com): Dinas Pertanian Kota Bekasi, Jawa Barat, mencatat sekitar 48.000 hektare persawahan di wilayahnya mengalami kekeringan akibat

debit air yang terus menurun selama musim kemarau.Sumber air dari waduk Jatiluhur melalui kali Tarum Barat terus menyusut selama musim KEMARAU. Saluran irigasi sawah di 23 kecamatan di Kabupaten Bekasi,

saat ini sudah kering seiring berkurangnya debit air tersebut. Wilayah paling parah di bagian selatan, seperti Kecamatan Cibarusah, Cikarang Selatan, Serang

Baru, dan Kecamatan Setu. Pompanisasi dilakukan untuk menjaga target produksi beras di Kabupaten Bekasi

sebanyak 631 ribu ton setiap kali panen tetap terjaga.

Diunduh dari: http://www.beritakendal.com/2012/07/02/puluhan-hektare-sawah-kekeringan/ ……… 25/12/2012

ANCAMAN KEKERINGANPULUHAN HEKTARE SAWAH KEKERINGAN

Puluhan hektare sawah di Dukuh Klampok, Desa Sendangsikucing, Kecamatan Rowosari mengalami kekeringan sejak satu pekan ini. Akibat kekeringan,

tanaman padi berumur satu minggu terancam mati. Petani kesulitan mendapatkan pasokan air dari saluran irigasi karena lokasinya jauh.

“Jika dalam jangka waktu tiga hari ke depan, pasokan air tidak ada, tanaman padi terancam mati,” (Menurut petani Sulaemi).

Setiap musim kemarau tiba, puluhan hektare sawah di dukuhnya kekurangan air. Selain itu, puluhan hektare sawah di perbatasan Desa Bulak- Sendang si kucing juga kekurangan air. Pemerintah diharapkan dapat membuat saluran irigasi yang

permanen agar air dapat mengairi lahan pertanian.

Diunduh dari: http://www.tempo.co/read/news/2012/09/07/179427953/Belasan-Ribu-Hektare-Sawah-Alami-Kekeringan ……… 25/12/2012

ANCAMAN KEKERINGANJum'at, 07 September 2012 | 00:51 WIB

BELASAN RIBU HEKTARE SAWAH ALAMI KEKERINGAN

TEMPO.CO, Surabaya - Kepala Bidang Produksi Tanaman Pangan Dinas Pertanian Jawa Timur, Achmad Nurfalakhi, mengatakan 13,9 ribu hektare sawah bertanaman padi di Jawa

Timur mengalami kekeringan. Sebagai dampak akibat kekeringan sawah, sejumlah tanaman padi mengalami puso (gagal panen).

Dinas Pertanian Jawa Timur mencatat, kekeringan paling luas terjadi di Kabupaten Bojonegoro seluas 5.410 hektare, Lamongan 2.102 hektare, Tulungagung seluas 2.102

hektare, Trenggalek 1.470 hektare dan Ngawi 948 hektare. Gagal panen yang dialami petani, menurut dia, terbagi dalam berbagai kriteria. Seluas

2.977,49 hektare padi mengalami gagal panen 100 persen dan 1.961 hektare gagal panen 75 persen. Selain itu, seluas 3.429 hektare mengalami kekeringan sedang (gagal panen 50

persen) dan seluas 5.588 hektare mengalami kekeringan ringan (gagal panen 25 persen).

TEMPO/Marifka Wahyu Hidayat

Diunduh dari: www.idosi.org/aejaes/jaes5(2)/18.pdf ……… 25/12/2012

ANCAMAN CEKAMAN AIRAmerican-Eurasian J. Agric. & Environ. Sci., 5 (2): 264-272, 2009

EFFECTS OF DROUGHT STRESS ON GROWTH AND YIELD OF RICE (ORYZA SATIVA L.) CULTIVARS AND ACCUMULATION OF

PROLINE AND SOLUBLE SUGARS IN SHEATH AND BLADES OF THEIR DIFFERENT AGES LEAVES

A. Mostajeran and V. Rahimi-Eichi

One of the main problems of rice cultivation and production is the lack of water resources, especially during periods of low rainfall which affect the

vegetative growth rate and the amount of yield. In this study the effect of low water supply on the number of heading per hill,

number of grain per hill, dry weight of vegetative tissues and panicle and 1000 grain weight in three new cultivars of rice including 216, 829 and Zayandeh-Rood were measured under submerged and non-submerged conditions in a randomize complete block design with three replicates.

Simultaneously, the variation in proline and total sugars in sheaths and blades of leaves at different ages was determined.

The data indicated that Zayandeh-Rood cultivar showed the lowest reduction in shoot dry weigh and the number of tillers per hill under

non-submerged conditions. Furthermore, the panicle weight and the number of filled grains per spike

were higher in Zayandeh-Rood cultivar than the other cultivars. In addition, the result of this study show that Zayandeh-Rood cultivar in

which originated from local cultivars, have higher ability in solute accumulation such as proline and total carbohydrates than the other new

lines.

Due to correlation between drought tolerance of Zayandeh-Rood and solute accumulation, it may be

suggested that the solute accumulation is one of the mechanisms for drought tolerance in rice.

Diunduh dari: http://www.ricesci.cn/EN/abstract/abstract887.shtml……… 25/12/2012

ANCAMAN CEKAMAN AIREFFECTS OF WATER STRESS ON RICE GRAIN YIELD

AND QUALITY AFTER HEADING STAGEZHENG Jia-guo; REN Guang-jun; LU Xian-jun; JIANG Xin-lu

Chinese Journal of Rice Science 2003, 17(3): 239-243 .

Pot experiment was conducted in 2000-2001.

Results showed that water stress reduced rice yield significantly within 25 days after 80% of full heading; the effects were very weak after 25

days due to water in soil could maintain rice physiological activity about 10 days.

The grain quality interrelated to the grain filling degree. It was better to keep water in paddy until 25 days after 80% of full heading for rice

quality cultivation.

Diunduh dari: http://www.ncbi.nlm.nih.gov/pubmed/17044492……… 25/12/2012

ANCAMAN CEKAMAN AIR. Ying Yong Sheng Tai Xue Bao. 2006 Jul;17(7):1201-6.

EFFECTS OF WATER STRESS DURING GRAIN-FILLING PERIOD ON RICE GRAIN YIELD AND ITS QUALITY UNDER

DIFFERENT NITROGEN LEVELS.Cai Y, Wang W, Zhu Z, Zhang Z, Lang Y, Zhu Q

To examine the effects of nitrogen (N) supply and water stress on rice grain yield and its quality, a pot experiment was conducted at Yangzhou University. Three rice cultivars were

grown under two N levels (high N and normal N) from initial heading, and two water conditions (well watering and water stress) were installed for each of the two N levels from

flowering to maturity.

The results showed that when the plants of test cultivars were grown under normal N level, water stress markedly reduced the grain-filling percentage and grain weight, resulting in a significant decrease of grain yield by 11.6% to approximately 14.7%. Though the head-

milled rice had a slight increase, the percentage of chalkiness was significantly increased by 18.7% to approximately 33.1%, which resulted in an inferior performance in grain-apparent quality. In contrast, when the plants were grown under high N level, water stress increased the grain yield by 18. 8% to approximately 22.2% because of the increase of grain-filling percentage and grain weight. As compared with well watering, water stress decreased the

percentages of chalky grain and chalkiness by 15.3% to approximately 37.2% and 13.7% to 29.9%, respectively, which improved the performance of grain-apparent quality. The

pronounced effects of N application and water treatment were observed on the RVA profile and cooked quality. Under both two N levels, water stress decreased the peak viscosity and

breakdown (except for Yangdao 6) while increased the setback.

According to the performance in the indices of cooked quality, the palatability became poor when subjected to water stress under normal N level, as the result of the increase of hardness

and cohesiveness. In contrast, under high N level, water stress availed the ascending of viscosity at the early stage when rice flours were pasting, peak viscosity and breakdown

were increased, and setback was decreased, suggesting that the palpability got well.

It was concluded that mild water stress during grain-filling period was benefit for the development of high quality grain when rice

plants were grown under high N level.

Diunduh dari: http://link.springer.com/content/pdf/10.1007%2FBF02902907……… 25/12/2012

ANCAMAN CEKAMAN AIRBIOLOGIA PLANTARUM (PRAHA)

26 (4) : 263--266, 1984EFFECT OF WATER STRESS AT DIFFERENT

DEVELOPMENTAL STAGES OF FIELD-GROWN RICEAJoY K. BISWAS and M. A. CHOUDHVRI

Water-stress for 10d at different developmental stages, affected relative water content and leaf water potential of plants. Subsequent rewatering removed

these effects. Water stress lowered the contents of chlorophyll, protein, RNA and the activity of catalase, while it increased free proline accumulation and activities of protease, RNase and peroxidase. An overall improvement in biochemical parameters was achieved as soon as the stress was withdrawn by watering and this was reflected

in subsequent developmental stages.

Water-stress at the reproductive stages induced similar changes as in the vegetative stage but the removal of stress

could not improve these parameters to the same extent as at the vegetative stage.

In consequence, stress applied at the vegetative stage augmented yield parameters but when applied at the reproductive stage it significantly reduced the yield.

Diunduh dari: http://www.regional.org.au/au/asa/2004/poster/1/3/3/1095_pirdashtih.htm………

25/12/2012

ANCAMAN CEKAMAN AIRStudy of water stress effects in different growth stages on

yield and yield components of different rice (Oryza sativa L.) cultivars

Hemmatollah Pirdashti , Zinolabedin Tahmasebi Sarvestani , Ghorbanali Nematzadeh and A. Ismail.

Australian Agronomy Conference. 2004 12th AAC, 4th ICSC.

Water stress affects plant growth and development and ultimately, reduces grain yield of irrigated lowland rice.

A field experiment was conducted during 2001-2003 to evaluate the effect of water stress on the yield and yield components of four rice cultivars commonly

grown in Mazandaran province, Iran. The cultivars used were Tarom, Khazar, Fajr and Nemat. The different water stress conditions were water stress during

vegetative, flowering and grain filling stages and well-watered was the control.

Water stress at vegetative stage significantly reduced plant height of all cultivars. Water stress at flowering stage had a greater grain yield reduction than water

stress at other times.

The reduction of grain yield largely resulted from the reduction in fertile panicle and filled grain percentage. Water deficit during

vegetative, flowering and grain filling stages reduced mean grain yield by 21%, 50% and 21% on average in comparison to control

respectively.

The yield advantage of two semidwaf varieties, Fajr and Nemat, were not maintained under drought stress.

Diunduh dari: www.academicjournals.org/jabsd/PDF/.../Fofana%20et%20al.pdf……… 25/12/2012

ANCAMAN CEKAMAN AIR. Journal of Agricultural Biotechnology and Sustainable Development Vol. 2(6), pp. 100-

107, June 2010

EFFECT OF WATER DEFICIT AT GRAIN REPINING STAGE ON RICE GRAIN QUALITY

M. Fofana, M. Cherif , B. Kone, K. Futakuchi and A. Audebert.

Rice production is usually reduced by water stress that can evenly occur during rice cycle in West Africa under bimodal rainfall pattern. In order to determine the effects of

water stress on rice grain quality, experiments were conducted on upland site (on ferralsol) at the main AfricaRice research center at M’be, 30 km North of Bouaké, Côte d’Ivoire. The rice varieties CG14 (Oryza glaberrima), WAB56-104 (Oryza sativa), and NERICA1 (cross WAB56-104 x CG14) were sown at 25 × 25 cm spacing during the dry season cropping period of 2000, 2001 and 2002. Irrigation line (Boon irrigation) was used to supply water until flowering stage. Water was then supply manually from

the milky stage of each variety to its full ripening stage. Physical (husking yield, milling recovery, and head rice ratio), chemical (amylose and proteins contents) and

cooking parameters (cooking time, volume expansion, rice flour gelatinization temperature, consistency and viscosity) of the harvested grains were determined in the

laboratory. The results showed a significant difference (p < 0.05) between all the parameters in

comparison with the checks samples and stressed crop. In general, NERICA 1 showed better physical and cooking quality traits than its parents. Rice samples from plots

subject to lower water availability during repining stage showed higher protein content for all varieties studied. Increase in the average protein content of stressed samples

were 31, 11.8 and 13.3% times, respectively for NERICA 1, CG14 and WAB56 -104, where (using the protein content of check plots as 100%) NERICA 1 showed higher

husking yield, total mean milling recovery and head rice ratio for samples collected on stressed plots than the glaberrima and the sativa samples recorded on similar plots.

Finding showed that cooking properties that meet West African rice consumers’ preferences for cooked rice were more improved for NERICA 1 than its parents in

comparison with samples collected from stressed plots. It is concluded that moisture stress at ripening stage should be further investigated as potential

indirect means of improving rice grain quality.

REKAYASA BIOLOGIS SUMBERDAYA HAYATI

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