Nathan LeggeProfessor Alex BlockWriting 10015 May, 2015Course Paper Final Draft

A Case for Sustainable Agriculture

Global climate change is destabilizing ecosystems across the planet. This has diminished

the function and output of natural and agricultural ecosystems globally, with economic impacts

in the form of rising food prices. The complex nature of ecosystems has led many agriculturalists

to rely on unsustainable methods of overexploiting soil with environmentally destructive

petrochemicals. One strategy of diminishing this reliance, here called the Ladder program, is to

enact organic methods in an effort to grow crops intelligently. The purpose of this program is to

create efficient, self-sustaining ecosystems from which sustenance can be pulled, one project at a

time. Despite criticisms that can be leveled against organic methods, they may inevitably become

necessary for the stabilization of food markets in the face of growing populations, dwindling oil

resources, and increasing global climate change.

In order to properly discuss the current global climate crisis, it is important to understand

the fundamental behavior of the Earth’s biosphere. Atmosphere and oceans absorb and

redistribute heat from solar radiation, and this regular process has created the mosaic of climates

found around the world today (Hannah 22). The rotation and revolution of the Earth around the

Sun creates a seasonal alternation of temperature and circulation of moisture to which all species

have adapted like a biological clock. The metabolism and growth of plants and bacteria are

highly sensitive to moisture and temperature in air and soil (Svenning and Sandel 1266). A given

plant has very slow and fragile biochemistry that relies on subtle temperature cues to guide its

maturation, so that it does not try to grow when water resources are too low (1267-1268). Thus,

when seasonal temperatures shift and rain patterns become irregular, only a certain number of

plants can cope with the increased stress. Those that do not cope either die or fail to properly

mature. In turn, the insects and animals which depend on the maturation of these plants

experience a lack of resources, which in extreme cases can lead to extinctions of species

(Srivastava and Vellend 278-279). Therefore, stable climatic conditions are desirable for species,

like humans, that depend on plants for sustenance. However, the Earth’s climates are in a

growing state flux, caused primarily by increasing atmospheric carbon dioxide.

Carbon dioxide (CO2) has been identified as the leading cause of global climate change.

Levels of atmospheric CO2 released by the decay of plants and burning of fossil fuels have risen

since the widespread use of coal and oil in 1940 (Svenning and Sandel 1266). Since 1960,

industrial emissions of carbon dioxide have quadrupled, and the total amount of CO2 in the

atmosphere has risen by nearly a quarter (Groot et al. 32; Ingram and Malamud-Roam 191). This

CO2 traps heat more readily than nitrogen and oxygen in a process known as the greenhouse

effect, and the natural absorption of CO2 by the Earth’s oceans is beginning to break down

(Groot et al. 34-35). The many ocean and air currents which distribute heat from the equator to

the poles are made unstable by this average temperature increase, resulting in erratic weather

patterns experienced in different ways by different regions (Leakey et al. 228). This can lead

relatively moderate climatic behavior to suddenly be divided between floods in California and

droughts in Indonesia, for example (Ingram and Malamud-Roam 53-54). The seasonal variation

in a given region may also be divided between extremely wet winters and extremely dry

summers, with an increasingly brief period of moderate weather needed for farming (196-197).

Shorter growing seasons have obvious implications for the output of human agriculture, but

changing temperatures also impact biodiversity, specifically.

As stated above, the maturity and reproduction of plants is interrupted when seasonal

temperatures and precipitation are shifted by the greenhouse gases like CO2. Normally, plants in

temperate regions increase growth in the presence of higher ambient CO2, thereby countering the

greenhouse effect and keeping local temperatures stable (Leakey et al. 233). However, crops

grown in other biomes may react differently as their climates become more erratic. In tropical

environments, a warmer atmosphere brought on by increased CO2 leads to more precipitation

and floods in the wet seasons and less precipitation and droughts in dry seasons. In arid

environments, precipitation is always low, so warmer conditions will spark prolonged droughts.

In frozen tundras, increased CO2 is predicted to increase thawing and release even more CO2

trapped in the ice (Leakey et al. 235). In each of these cases, there is a threshold beyond which

plants cannot counteract increased CO2 because the rate of temperature increase is too high. Rice

has been observed to cross this threshold and decrease productivity in spite of higher CO2 levels

(Leakey et al. 234). If such a threshold exists for temperate plantlife, the biological

counterbalance to increased CO2 will begin to break down in what is most likely an irreversible

cycle of increased atmospheric CO2, increased ambient temperature, and decreased CO2

absorption through photosynthesis. Should such a chain reaction prove unstoppable, biodiversity

loss will not be halted by human efforts. The result is hard to predict, but this breakdown is

expected to decrease the function and output of ecosystems on a global scale.

The utility of ecosystem function demonstrates itself through food prices around the

world. India’s agricultural industry employs over half the nation and provides nearly a fifth of its

Gross Domestic Product. This makes one of the top-ranking agricultural powerhouses, owed in

large part to the adoption of expensive and destructive industrial farming practices (Ahmad,

Alam, and Haseen 131). These practices are the leading producers of greenhouse gases to date,

and were adopted by a list of third world countries over the last century. In a study of this

industry in India, Jamil Ahmad, Dastgir Alam, and Shaukat Haseen (130) estimate an increase in

global temperature by two degrees could offset the growth cycle of crops enough to cost India

nearly half of its GDP. This, combined with an ever-growing population, will have destructive

effects that will not be unique to India. As climates shift, established farms will find it more

difficult to grow crops, and this will drive food prices higher. The cost of basic necessities will

disproportionately impact the poor and impoverished, with potentially destabilizing results for

developing nations (Cohen, Shepherd, and Brown 250; Berazneva and Lee 2013). Knowing this,

the necessity to protect ecosystem function is undeniable.

In 2007, Groot et al. (50) reviewed a dataset of 320 ecological studies to estimate the

monetary value of different biomes. Coral reefs, coastal wetlands, and inland wetlands are ten to

sixty times more valuable than all other biomes, including tropical forests (55). Needless to say,

the exact values of these biomes are and controversial (Svenning and Sandel 1266). The most

accurate statement is that human economies could not exist without crops growing and natural

water distribution the way it is today. In unstable climatic conditions, large predators at top

trophic levels are at highest risk for extinction, which means food webs crumble from the top

rather than from their foundations (Srivastava and Vellend 278-279). This means humans, who

depend on higher trophic levels than lower levels, will suffer greatly from climatic instability.

Through their research, Clewell and Aronson (425-426) claim that mature, complex ecosystems

regulate climate better than less complex ones by absorbing and distributing solar radiation in the

form of biomass. This is one ecosystem function that is directly dependent on biodiversity,

though its contribution to climatic stability may be infinitesimal compared to geological

processes (Groot et. al 22). In short, the necessity of ecosystem function is absolute, but the

importance of biodiversity to that function is not well understood.

Rising global temperatures caused by ambient CO2 levels can spark a feedback loop that

divides mild climates into extreme drought and extreme floods. Ecologists have estimated the

threshold of this loop at two degrees centigrade above 2001 levels (Ahmad, Amal, Haseen 130).

The vast majority of green policies aim to keep global temperatures from crossing this threshold

through plans to reduce carbon emissions and increase renewable sources of energy. Current

trends, however, show that this strategy has not been as successful as was hoped or needed

(Everard et al. 358). This is due to a number of obstacles, including political gridlock and lack of

public funds. Additionally, well-established farmers remain convinced that private gains at

public loss, such as slash-and-burn agriculture and soil overexploitation, are necessary in a

competitive market (Petersen and Snapp 7). Though rising global temperatures present the most

universal cause of ecosystem collapse, a loss of biodiversity has a number of causes which may

or may not contribute to poor agricultural performance.

In a journal concerning environmental policy, Jorge Soberón (11) identifies immediate

and mediate causes of biodiversity loss. Immediate causes include overexploitation of biological

resources, introduction of invasive species, and use of artificial chemicals. In short, any practice

which depletes biomass or otherwise impacts a given ecosystem is liable to interrupt long-

standing equilibriums between species. Doing so creates artificial pressures on certain species,

increasing tendencies towards extinction and threatening the stability of entire foodwebs. Each of

these causes will be discussed in turn.

One of the most obvious stressors on local ecosystems is the overexploitation of certain

species (Soberón 12). Farming has isolated most desirable species from their natural habitats to

prevent them from being eaten by other organisms. A ready example of overexploitation leading

to ecosystem instability is in the harvesting of fish. By harvesting vast quantities of fish, humans

are effectively draining the oceans of biochemical matter to such a degree that other fish are

prone to extinction (Beamish MacFarlane and Benson 289). Overgrazing can leave otherwise

lush grassland as uninhabitable desert (Ahmad, Alam, and Haseen 130). Deforestation and

improper irrigation causes ecosystems that have developed over thousands of years to

disintegrate. Such erosion has immediate and undeniable effects upon human subsistence

practices. Soil erosion has been a known symptom of overexploitation since the 1930s Dustbowl

sandstorms (Ingram and Malamud-Roam 42). Since that time, however, agricultural practices

that lead to erosion have continued in many countries (Ahmad, Alam, and Haseen 130; Soberón

12-13). More specifically, artificial fertilizers have become an industry standard that would not

be necessary if crops were grown in self-sustaining ecosystems.

The introduction of invasive species is another destabilizing influence on ecosystems

(Soberón 12). Some species have been introduced to foreign environments through direct human

action. Certain species, if they are particularly successful in a new environment, have the ability

to take over a biological niche, driving indigenous species to extinction and possibly causing

further reverberations throughout an ecosystem. In a more global and indirect trend, invasive

species are introduced by migratory trends spurred by global climate change. Warming trends

have affected the hospitable range of certain species, along with their maturation times and

population size (Rosales 1410). For example, increased temperatures in the Southern California

mountains allowed bark beetles to proliferate throughout vast tracts of pines, which ultimately

led to giant wildfires (Ingram and Malamud-Roam 194). The destructive nature of such pests has

led conventional farmers to rely on pesticides, herbicides, and rodenticides derived from fossil

fuels to effectively kill all organisms in a given area besides the crops themselves (Mahmood,

Bilal, and Jan 423). These protect crops at the expense of all other living creatures, and deserve a

deeper explanation for the purposes of this paper.

Because ecology is so little understood, farmers rely on nebulous foodwebs to foster the

growth of microbes and insects that enable the growth of their crops. These foodwebs are

threatened by climatic instability, and any negative impacts on them will translate to lower crop

yields (Ahmad, Alam, and Haseen 130). To buffer these negative climatic effects and maximize

profitability, farmers have come to rely on petrochemical pesticides, herbicides, and fertilizers

that extract more food than soil would naturally be able to support (Connor 187). Roughly 99.7

percent of agriculture around the world is directly supported by petrochemicals (Ibid). These and

other chemicals released by human practices have proven toxicological effects, as should be

expected from industrial poisons (Mahmood, Bilal, and Jan 423; Snow 37-42; Soberón 12).

Setting aside the detrimental effect that these chemicals undoubtedly have on natural ecosystems,

their use on arable cropland has created ecosystems that are unsustainable by design. This is

enough reason to abandon conventional agriculture as quickly as possible, but there are others.

The conventional method of growing crops is to throw petrochemicals on soil to the

extent that it is capable of growing only the crop and nothing else (Crowder and Harwood 2). By

destroying a natural ecosystem to keep crops safe from pests, farmers create tracts of land wholly

dependent on artificial fertilizers to produce food (Mahmood, Bilal, and Jan 423). When this

supply of fertilizer stops, the crops die and the bare soil erodes (Ingram and Malamud-Roam

2013 44-45). So long as petrochemicals are used, crops can be protected from invasive species

and disease. Yet even this petrochemical buffer faces increasing pressure from global climate

change. Ecologists have placed the global temperature threshold at two degrees centigrade above

2001 levels (Ahmad, Amal, Haseen 130). Past this threshold, global temperatures will overpower

the stabilizing capability of temperate plants and CO2 levels will spiral out of control (Nemergut

et al. 2005 782). In the ensuing temperature rise, farmers will come to rely on petrochemicals

more than ever at continuously rising prices. This reliance on petrochemicals makes the price of

gas the most important factor for farmers when they could instead hire skilled entomologists,

surveyors, and biochemists to make their crops self-sustaining. In time, even the most costly

alternatives will seem viable, and farmers will be looking for any way to reduce their dependence

on oil products. This is where the Ladder program comes in.

The Ladder program is an attempt to construct a functioning ecosystem with as few

species as possible, so that those species can be easily monitored and protected by human

biochemists. This will also maximize the efficiency of the ecosystem, as less energy will be

diverted by unnecessary or redundant species. In addition, the Ladder program calls for an

increase in organic methods to reduce dependence on expensive and toxic petrochemicals. In this

case, organic methods range from genetic modification to microbial pesticides. The most

promising and least expensive of these methods includes promotion of natural enemies, meaning

species which naturally eat or attack pests. In short, this plan calls for more intelligence about

farming than is currently practiced in conventional agriculture. Plants and soils will need to be

closely monitored and treated for infestations and diseases using organic materials—preferably

produced with organic methods. The ultimate goal of this program is to create an ecosystem with

as few trophic levels as possible between humans and soil. If humans harvest a measured amount

of this ecosystem’s produce and contribute enough waste products to compensate, this ecosystem

will end by needing very little human oversight.

The first Ladder project will be the most difficult, and will set the template for other

projects in the same biome. First, an isolated tract of land free of petrochemical contamination

must be properly irrigated. If the soil is already irrigated and fertile, constructing the ecosystem

will be much faster. Before commercial crops can be planted, a functioning ecosystem must be

established to support them. This means transporting manure from livestock farms and beneficial

insects from their natural habitats. Properly irrigated, a project requires evergreens or

myrmecophytes to serve as nests for natural enemies. Natural enemies can be ants, spiders, or

some other natural insectivore. If these insectivores do not also serve as pollinators, bees must be

included and serve as food for the insectivores. This would make pollinators a primary resource

for the whole project, so they must be monitored carefully. This means beekeepers, surveyors,

biochemists, and botanists must be employed year-round to counteract environmental impacts

and diseases within this ecosystem. Such would require a deeper understanding of botany and

soil ecology, so a major element of the Ladder program is research into every aspect of this

artificial ecosystem. Surprisingly, the vital field of ecology remains underdeveloped.

The difficulty in understanding the ecosystem function stems from a limitations in the

field of ecology. Most practical tests of biodiversity deal with number of species as a lump sum

and assume all species perform unique functions. By contrast, Thompson et al. (689) recommend

a foodweb approach, which charts the links between one niche and the next. Such an approach

would allow fluctuations of a given resource (nitrogen, calcium, etc.) in a given niche (riverbed

soil microbacteria) to be observed for its effects on one species and its predators. Through this

method, ecosystem function may be observed to depend on a select number of keystone species.

Unfortunately, the intensive nature of such a study precludes it from being carried out as these

authors suggest (Nemergut et al.776). Despite these limitations, less thorough species-removal

tests suggest that the biomass needed to maintain large animals at the highest trophic levels is

dependent on a select number of species (692). In every case, the necessary species for any

ecosystem to function begins with bacteria in soil.

Unfortunately, microbial species are the least understood and most difficult to observe.

Molecular phylogentic methods have recently been used to help identify microbial taxa, but these

have yet to see widespread use (Nemergut et al. 776). On this subject, Hillebrand and

Matthiessen (1406) raise an interesting point. The list of keystone species that contribute a given

function may be short, but there is usually little overlap between this list and the list for another

function (Hillerbrand and Matthiessen 1406, 1409). In other words, it is a mistake to assume that

the keystone species necessary for growing corn can also be used to grow oaks or oxygenate air.

It is often the case that certain species are optimized for utilization of a specific resource to the

detriment of other resources, so variety of species is needed to efficiently process all resources.

This complicates the reduction of ecosystem function to a handful of keystone species, and

requires consideration of most or all necessary functions together, rather than letting one function

speak for the rest.

Niche theory offers a way around this problem (Hillebrand and Matthiessen 1413; Bent

and Forney 689). A niche is a specific place in an ecosystem occupied by one or multiple

species. These species prey on certain other species, and are in turn preyed upon by their

predators. In this way, biomass and energy are transferred between niches, and fluctuations in the

growth of one niche have effects on all the niches that prey upon it. Supposing an invasive

species of ant drives several others to extinction, so long as it fulfills the same niche, ecosystem

function has not been disrupted. In the same way, the specific species dedicated to oxygenation

can be ignored for practical purposes, and the soil itself can be treated as a single species. In

other words, if humans can identify the chemical inputs (carbon, nitrogen, water, etc.) necessary

to make soil produce a useful output (heat, proteins, biomass, etc.), what happens in between can

remain a mystery. In short, keystone microorganisms are so difficult to identify that, for the

purposes of this paper, soil will be considered as a single species. Thus far, research is

inconclusive as to the impact of climatic behaviors like increased temperatures on soil

production and biodiversity (Nemergut et al. 782). If soil biology were properly understood, a

Ladder project would have a stable foundation from which to introduce other useful species to its

artificial ecosystem.

Once microbial colonies have been established, the task of project managers is far from

over. Soils and the species that grow to depend on them must be carefully monitored, especially

in the initial years of a project. Most importantly, managers must refrain from the temptation to

accelerate growth with artificial fertilizers, as this may cause a population explosion and

subsequent starvation. For the purposes of this program, organic materials are those that are not

chemically treated or converted from fossil fuels. This does not mean gasoline transport of

materials is forbidden, nor does it mean livestock from which manure is obtained must also be

organically fed. If, however, any element apart from water is needed that the ecosystem cannot

eventually produce on its own, it cannot be called self-sustaining. For this and other reasons, the

Ladder program calls for total abandonment of petrochemical usage. The real question remains

how farmers can convert irrigated land from conventional crops, which are essentially grown on

dead land, to fully developed ecosystems prescribed by the Ladder program. This cannot be a

smooth transition, but the success of the first project will entice farmers to try.

One legitimate criticism of the Ladder is that it cannot work without a proper water

supply and gives no indication of how one can be attained. Water supplies promise to become a

major concern, given the current transformations of the Earth’s climates. The Ladder plan

deliberately leaves water management out of the equation. Since water is a basic resource very

obviously needed for crops to grow, this plan will treat it as a variable. In other words, both

conventional and organic methods are successful to the degree that they have a supply of water.

Therefore, improving and protecting irrigation will be left for some other plan.

The primary task of botanists and surveyors will be to repel unwanted pests and diseases

through the stimulation of natural enemies. There are a host of organic methods for biological

control ranging from plant pathogen to microbial pesticides (TeBeest 116). Some plants are

currently being genetically modified to passively combat pests, but other methods are more

reliable (Petersen and Snapp 6). One promising area of biological utility lies in the use of

insectivores to kill pests in place of chemical pesticides. Decreased use of pesticides in turn

allows lady beetles, spiders, and other natural enemies to increase their numbers (Crowder and

Harwood 5). Examples of natural enemies which may prove ideal for organic agriculture are

myrmecophytic ants, which have symbiotic relationships with benignly parasitic plants in

tropical regions (Perfecto and Castaneiras 269-276). These plants emit chemicals that attract the

ants to defend against herbivores, in return providing shelter for the colonies. Myrmecophytic

ants are receiving attention from farmers in South America, Africa, and Indonesia for their

perceivable benefits to commercial crops (Ibid). For the most part, however, use of living

creatures to counteract pests has had limited and poorly documented success (Crowder and

Harwood 4). Additionally, there is the problem of natural enemies killing pollinators like honey

bees (Crowder and Harwood 4; Grixti et al. 76). If this becomes a problem, pollinators may

become the most vulnerable elements in Ladder projects, as they are in conventional agriculture

(Brittain and Potts 322). Successful natural enemies, pollinators, disease resistance, and soil

cultures combine to create what should be a stable ecosystem ready for farming.

Should a Ladder project prove fruitful, there are unforeseen consequences that arise if

these organic methods work too well. For example, invasive species emigrate from managed

farm land to unmanaged natural land and vice versa. Blitzer et al. (35) provide an overview of

this dynamic. Most current literature shows the impacts, both positive and negative, of natural

species encroaching on managed land. What seems to be missing are records of impacts, mostly

negative, of species moving in the opposite direction. A common occurrence is a pest explosion

caused by the concentration of crops in such a small area (Blitzer et al. 36). Once these crops are

consumed or harvested, the exaggerated pest population emigrates and overexploits the untamed

plants in the surrounding countryside. The use of territorial insectivores is one way of avoiding

this. The unintended success of domesticated over wild species can prove problematic, but next

to pesticide use, these consequences are comparatively benign and manageable (Mahmood, Bilal,

and Jan 423). The nature of pesticides means they cannot be used in conjunction with natural

enemies—at least in the absence of genetic modification (Dewhurst 2001 67-68). In this and

many other ways, the destructive nature of many conventional methods disrupts natural

functions. Consequently, the only way to maximize organic output is by omitting petrochemicals

altogether, and this is one requirement of the program.

Funding for these projects will be most difficult. As of 2008, organic crops represent only

0.3 percent of total agriculture on the planet (Connor 2008 187). There have been three major

initiatives to adopt organic agriculture, all of which have fallen through (Ibid). It is time to

acknowledge that conventional agriculture and perhaps the whole of human civilization is

hopelessly dependent on petrochemicals. However, this does not make organic farming a lost

cause. Dwindling oil resources and increasing populations mean petrochemicals will inevitably

become more expensive. This means more farmers will opt for organic methods, and the Ladder

is intended to maximize these farmers’ production while minimizing costs. Because the program

requires the complete absence of petrochemicals, individual transitions from conventional to

organic methods is not a smooth process. However, in the event of oil decline, this program will

enable a smooth transition to organic methods on a national and global scale. In fact, as long as

climates remain favorable and societies refrain from overexploiting organic ecosystems,

agricultural land may become so self-sustaining as to survive a major economic collapse that

would leave conventional cropland dead and eroded. As with any renewable resource, the initial

investment will pay off more over time than immediate conventional methods.

One obvious criticism of the Ladder program is that it aims to distract from green

initiatives by minimalizing the economic impact of climate change. There is no doubt a drastic

reduction in biodiversity and global ecosystem function is catastrophic. It is true that a reduction

of human misery works against efforts to solve the larger goal of counteracting climate change,

but since the end goal of green policies is to reduce human misery, this is hardly a criticism.

Unfortunately, even a successful Ladder program will not reduce global reliance on

petrochemicals. It is more than likely that organic methods on some crops will reduce the price

of oil such that other farmers will continue to use oil products on certain crops. However, if

organic methods prove successful, trends such as population growth and peek oil will eventually

force the majority of agriculturalists organic methods. Hopefully, a successful Ladder program

will make the resulting transition from conventional to organic methods less sudden than it

would be otherwise.

The most damning criticism of organic agriculture is that it simply cannot support the

current human population of the planet. If this is a criticism of organic methods, it is an even

greater criticism of the agriculture industry as a whole, which is now overwhelmingly dependent

on non-renewable resources (Connor 2008 187). This means any fluctuations in the price of oil

can have catastrophic results, as witnessed in the African food riots during the 2008 recession

(Berazneva and Lee 2013). Furthermore, if so-called “Peak Oil” is a reality, this situation will

most assuredly deteriorate, but these are not the only reasons to adopt organic methods. The

negative impact of pesticide and herbicide use to human health and that of other species has been

extensively documented (Dewhurst 2001 67-68). Supposing organic methods have failed to

improve since 2008, this does not change anything stated above. The current state of affairs is

unstable and unhealthful. To the degree that conventional methods become too expensive, the

Ladder program will be more enticing. However, this program is not simply encouraging or

greater use of organic methods; it demands total disuse of petrochemicals in order to build self-

fertilizing ecosystems. If this cannot support human economies, it is time for societies around the

world to reassess their futures with respect to static or dwindling oil resources.

In light of global climate change, the Ladder program or something very similar must be

implemented. A progressive dogma has convinced so many people that energy and resources will

continue growing to support human populations. A combination of population growth, dwindling

oil production, and rising climate instability threatens the reliability of conventional agriculture.

It is time to take steps away from the gasoline high while there is still time left for a smooth

transition to self-sustaining agriculture. If organic methods seem impractical now, the simple

passage of time may change this opinion. Until that time, the Ladder program will be waiting.

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