Activity 1. Climatological Factors in the Ecosystem and Ecological

Properties of Soil and its Inhabitants

Renzo Val Agapito, Miguel Luis Chua, Rayniel Frio and Malaya Turzar

Biology Student, Department of Biology, College of Science, Polytechnic University of the Philippines

Abstract

The climatic factors include rainfall and water, light, temperature, relative humidity, air,

and wind. They are abiotic components, including topography and soil, of the environmental

factors that influence plant growth and development. Edaphic factor is defined as 'ecological

influences properties of the soil brought about by its physical and chemical characteristics. In

this study, an open area, shaded area and area inside a building were located and measured its

physical conditions and provide temporal information. Also, soil samples were collected and

determined its texture, moisture and analyzed its organic matter content and inhabitants of the

soil. For the results, it was determined that the aerial temperature in open area has the highest

temperature, precipitation and evaporation. The soil samples were determined as alkaline loamy

sand type of soil with low percentage water and organic matter.

Keywords: climatic factors, edaphic factors, light, temperature, relative humidity, air and soils

Introduction

Climate is the long-term, prevailing

weather conditions in a particular area as

Mark Twain would differentiate “Climate is

what we expect, weather is what we get”

(Miller, 2009). Climatic factors particularly

temperature, and water availability have a

major influence on the distribution of

terrestrial organisms. They are abiotic

components, including topography and soil,

of the environmental factors that influence

plant growth and development (Campbell,

2009). Climate may be classified on two

scales macroclimate and microclimate.

Macroclimate is the patterns on a global,

regional and local level, whilst the latter is a

very fine pattern such as those encountered

by the community of organisms that live

beneath a fallen log (Campbell, 2009).

This study focuses more on the

microclimate than the macroclimate, given

that areas to be examined are within

Polytechnic University of the Philippines,

Mabini Campus. Therefore this aims to

identify the influences of microclimates by

casting shade, affecting evaporation from

the soil or simply the change in wind

patterns.

In macroclimate there is said to be

three major factors that affects climate, one

is the uneven heating of the earth’s surface

by the sun, second is the rotation of the earth

on its axis and last, is the properties of air,

water and land. If these macroclimatic

factors were to be rationalized to get the

microclimatic factors it would be the light

intensity a certain area is amenable to,

humidity and still the same, properties of

water, air and land in that area.

Climates have loving organism that

prefer varying measurement of temperature,

humidity and etc., great number species of it

are inhabitant to the soil. Climatic factors

such as light intensity, temperature,

humidity, evaporation, precipitation do

affect living organisms as well as the habitat

they take shelter in, but aside from the

climatic factors also affecting those habitat

another factor termed as edaphic factor is

recognize to understand the soil factors

affecting its inhabitants. The diversity and

the measurement of diversity are central to

many issues in ecological research as well as

for applying ecology to real world problems

(Boyce, 2005)

Truthfully, tropical ecosystems

exhibit several ecological characteristics that

make their sustainable management a

difficult task (Fonge, 2011). By studying

some basic protocols in measuring edaphic

factors and climatic factors, this study in

general aims to practice basic skills that can

be used in furthermore applications in

ecology.

Methodology

Physical Conditions

An open area, shaded area, and an

area inside a building were located within

the campus. In each environment, five

random points were selected within the

assigned area were assessed to measure the

physical conditions. Illustrations and

descriptions of the environment were taken

(e.i substrate, plants and animals present),

temporal information (e.i the time when

measurements are made, weather, condition

of the sky) were also provided.

Temperature

The temperatures of the given areas

of study were measured using a laboratory

thermometer. The thermometers were

suspended for about three (3) minutes before

any reading was taken. The values were

recorded in Celsius.

Amount of Precipitation

The precipitation was measured

through the use of rain gauge. The amount

of the precipitation were collected and

measured after 24 hours and the values were

expressed in millimeters per day.

Precipitation data can also be gathered in

local weather station as alternative source.

Rate of Evaporation

In the study area, two pans with

known values of water were placed. After 24

hours, the volumes of the water left in the

pans due to evaporation were recorded. The

results were expressed in millimeters per

day.

Collection of samples

Soil samples were collected from a

random spot on the linear park of

Polytechnic University of the Philippines.

Using a trowel, the ground was dug up to 12

inches deep. Samples were collected per

horizon caught up by the digging. Moisture

of soil samples was then categorized

qualitatively.

Temperature

The soil temperature was determined

by burying a thermometer in the soil making

a total of 5 readings per horizon. Data

gathered were then recorded.

Soil pH

Equal amounts of soil sample and

distilled water were mixed in a beaker. Soil

particles were settled down until the

supernatant was relatively clear. The pH was

quantified using a pH meter.

Soil moisture

The soil moisture was quantitatively

analyzed by weighing a crucible and 10

grams of the sample then putting it inside

the crucible. It was then oven dried at 105º

C for 24 hrs. It was then weighed again with

the container. The %water in the sample was

calculated by dividing the water content

(original weight - dry weight) by the dry

weight multiplied by 100.

Organic Matter

From the oven dried samples, 1.5 g

sample was weighed and was placed in a

weighed crucible. It was then ignited

overnight with 450º C in a muffle furnace.

The sample was then cooled using a

desiccator and the weight after ignition was

recorded. The loss of weight after ignition

gives the organic content of the soil. It was

then expressed in percentage of the original

sample.

The soil suspension used in

analyzing the pH of the soil was used to

determine the following:

Soil Calcium

10 drops of soil supernatant was

added in a test tube with 10 drops of

solution (5 g ammonium oxalate in 100 mL

distilled water). It was then mixed until

precipitation occurs. Milky white precipitate

indicated the presence of calcium.

Soil sample was placed in a crucible

then excess 10% HCl was added. The sound

that the soil made on reaction was observed

to give the approximate levels of calcium

carbonate using the table given.

%CaCo3 Audible

effect

Visible effect

<0.1 None None

0.5 Faint None

1.0 Faint-

Moderate

Barely Visible

2.0 Distinct,

Heard Away

from Far

Visible from

Very Close

5.0 Easily Heard Bubble Up to

3mm

Easily seen

10.0 Easily Heard String

Effervescence

with Bubble of

7mm

Results and Discussions

Climatic Factors

There are a lot of factors that can

affect our climate. For this activity,

instructions in measuring temperature,

humidity, evaporation, precipitation and air

pressure all of which are factors that can

affect the climate were done.

For comparison, three general areas

were used to gather varying climatic factors

that can help to identify the effect of these

factors. (See table 1) For the shaded area

Polytechnic University of the Philippines

(PUP), Linear Park was chosen, whilst for

the open area PUP Oval, seemed to be the

apt choice, lastly for the building, PUP

Building, South Wing was used, description

of the locations was gathered to properly

weigh the varying results of each area.

Temperature, light intensity, relative

humidity, wind speed and direction,

atmospheric pressure, rate of precipitation

and rate of evaporation are climatic factors

that are considered to have an abundant

ecological significance. For temperature,

different organisms benefit from different

temperature as they have different cellular

tolerances for cold and heat, and also

temperature contributes to the erosion and

creation of soil.

Life in any ecosystem is strongly

affected by sunlight’s intensity, daily

duration and angle of incidence of the sun

(seasonal changes). Photosynthesis is driven

primarily by light in the blue and red regions

of spectrum; under story and underwater

regions have varying levels of these

wavelengths, with red light being lost first

and blue light last. The intensity of light can

change with the time of the day, season,

geographic location, and distance from the

equator, and weather. It gradually increases

from sunrise to the middle of the day and

then gradually decreases toward sunset; it is

high during summer, moderate in spring and

fall, and low during wintertime.

Relative humidity regulates the

evaporation of water from the body of land

organisms during transpiration and

perspiration, it promotes the growth of

epiphytes and it promotes the germination of

spores in fungi. Precipitation is the

condensation of atmospheric water vapor

into earth’s surface.

Precipitation is a critical

phenomenon of our environment. It

regulates the circulation of water in the

environment. Evaporation is an important

process in the global water cycle. Solar

radiation hits the surface of water or land

and causes water to change state from a

liquid to a gas. This is how water vapor

enters the atmosphere: moisture in the

atmosphere is linked to cloud formation and

rainfall.

Evaporation acts like an air

conditioner for the surface because heat is

used when water enters the atmosphere as

moisture. But at the same time, water vapor

acts as a greenhouse gas by trapping

radiation in the lower atmosphere. As

temperature increases so does the process of

evaporation. In addition the moisture

holding capacity of the atmosphere increases

with temperature. For every 1oC increase in

Table 1. Description of the area tested

Shaded Area

Open Area

Building

Time 8:45 am

9:00 am 9:15 am

Area PUP Linear Park

PUP Oval

South Wing Building

Sky Clear Clear Clear Weather Sunny Sunny Sunny Plants Present

(mostly trees)

Present (mostly grasses)

None

Animals Present (mostly ants and beetles)

Present (mostly ants and beetles)

None

global temperatures there is a 7% increase in

the moisture holding capacity of the

atmosphere. And more moisture in the

atmosphere ultimately leads to changes in

rainfall patterns. Actual evaporation depends

on availability of water, for example more

water is evaporated from a lake than from

dry soil. Moist areas like tropical rain forests

have higher evaporation rates than arid

regions. The amount of water that

evaporates from the land surface depends on

the amount that is contained in the soil (soil

moisture).

Based on the results of measurement

of some climatic factors (See table 2), aerial

temperature varies greatly amongst the two

because of factors such as exposure to

sunlight, the highest temperature which is

the open area, is directly exposed to the

sunlight, whilst the lowest value which is the

building is also affected by the place’s

exposure to sunlight, meanwhile in the

shaded area, minimal light is available and

therefore having a mid-temperature (figure

1). The amount of natural light that may

enter a building is affected by the location of

windows or glass surface through which

light enters, the presence of trees and shrubs,

roof overhangs, window screens and

awnings, and the tint and cleanliness of the

glass. A gray glass allows 41% light

transmission while clear glass allows

89%.Within a building, the amount of light,

whether natural or artificial, will be further

affected by curtains and blinds, surface

textures, and reflectance from wall

coverings, furniture, and other furnishings

(Manker 1981). Other factors that might

have affected the aerial temperature is the

congestion of people in that area, also the

Table 2. Measures of some climatic factors

Shaded

Area

(Linear

Park)

Open

Area

(Oval)

Building

(South

Wing)

Aerial

Temperature

30° C 38.8° C 24.9° C

Amount of

Precipitation

90

ml/day

85

ml/day

98

ml/day

Rate of

Evaporation

88

ml/day

82

ml/day

97

ml/day

wind current that can be experienced

strongly in the PUP Linear park.

If one desire, to easily access the

variations of the climatic factors one can

use a climatograph it shows the

precipitation and the temperature of a

region. Climatographs can be used to look

at trends in climate as well as yearly

temperature or precipitation minimums

and maximums. It is very easy to use

climatographs to compare a city in one

biome to a city in another. There are two

types of climatographs are Precipitation

and Temperature climatographs.

Precipitation: A bar graph showing how

much precipitation a given place receives

during a period of time. Temperature: A

line graph shows the temperature

conditions for the same place during the

same period of time. Weather scientists

use a climatograph to predict

precipitation for various places. An

examination of more than one

climatograph can identify weather trends

such as Global warming. By using a

climatograph there would be a universal

quantitative analysis of the climatic

factors.

Edaphic Factors

Edaphic or soil factors is important

because of the intimacy of contact between

the plant and soil through the root system

and that both plant and soil are strongly

influenced by each other, although the soil

itself is full of life and is the habitat for

many organisms (Chastain, 2007).

Ecological properties of the soil show how

both the living and the non-living

environments affect soil community

structure and diversity (Swift et. al 1979).

Polytechnic University of the

Philippines, Mabini Campus (PUP), Linear

Park soil properties information was

collected. Table 3 shows the two horizons

present in the location namely, O horizon

and A horizon. O horizon is the organic

matter containing layer where a mixture of

broken-down rock of various textures, living

organisms and decaying organic matter were

found. On the other hand, A horizon or the

surface soil contains much less organic

matter than the O horizon and is less

weathered but, this is where mineral matter

with some humus is present (Campbell,

2009). (See Table 3) O horizon is black in

color, with small rocks, litter and plant

residues, it is about 0-2 inches think and had

a temperature of 28°C, whilst A horizon is

relatively lighter in color with insects and

fine layer of soil with absence of rocks and

, the depth was about 3-12 inches having

29°C temperature.

Given the description, the soil

moisture is determined as dry soil while the

texture is loamy sand. The structure can

affect the capacity of the soil to hold water

and other organic materials. The water

drained from the pores is replaced by air. In

coarse textured (sandy) soils, drainage is

completed within a period of a few hours. In

fine textured (clayey) soils, drainage may

take some (2-3) days. After the drainage has

stopped, the large soil pores are filled with

both air and water while the smaller pores

are still full of water. At this stage, the soil is

said to be at field capacity. At field capacity,

the water and air contents of the soil are

considered to be ideal for crop growth.

Soil texture is a classification system

based on mineral particle size. It is a

relatively permanent feature of the soil that

does not change appreciably over a human

lifetime. Soils are classified according to

the percentages of oven-dry weights of sand,

silt and clay. For example, a sandy soil is

composed principally of large sand particles,

whereas a loam contains more or less equal

amounts of clay, sand and silt.

Based on the information gathered in

soil moisture analysis (See table 4), from 10

g of soil sample, after oven drying, the

weight was reduced to 9.7759 g by finding

the difference of the two it was determined

that the weight of water was only 0.2472 g

of that 10 g or only 2.53%. The percentage

of water present is the soil is relatively

average, considering that when the soil

sample was taken the sky was clear and

bright and also, considering that the area is

supposed to be a well maintained region for

Table 3. Soil horizons description Soil Horizons Color Structure Thickness Temperature

O Horizon Black in color With small rocks, litter, plant

residues

0 – 2 inches 28° C

A Horizon Relatively lighter in color

With insects, fine layer of soil, no rocks, no litter

3-12 inches 29° C

Table 4. Soil moisture analysis Soil Moisture Soil Texture Dry Weight

Weight of

Water

Percentage Water

Dry soil Loamy sand 9.7759 g 0.2472 g 2.53 %

cultivating plant in PUP.

Organic matter is excluded from the

texture classification. Soils with high silt

content and those with high clay content

have greater capacities for retaining water

and available nutrients than sandy soils. By

adding small amounts of clay minerals to the

soil and by encouraging the activities of

earthworms to reduce the size of soil

mineral particles, organic farmers can

modify soil texture to a small degree, but the

greatest effect of these amendments is on

structure, as discussed above. (See table 5)

The organic matter present in the location

was 80%, this percentage is beneficial to the

soil as it was discussed above, because of its

capacity to sustain water.

CEC (Cation Exchange Capacity)

measures the quantity of potentially-

available cation nutrients that are in a stable,

accessible form. It is measured in milli

equivalents (me) per 100 grams of soil.

Typical values are 6.3 me/100g for sand and

27.2 me/100g for clay/loam; the higher the

CEC, the greater the potential fertility of the

soil. This is why clay soils tend to be more

fertile than sandy soils, and why the fertility

of sandy soils can be improved by the

addition of clay and humus. The cation-

exchange process can howe

ver only store and release positively-

charged nutrients; the availability of

nutrients in anion form, such as phosphorus

and sulfur is not affected by CEC. Soil

organisms play a key role in conserving and

releasing these nutrients.

The soil pH was also gathered along

side with the presence of calcium, calcium

carbonate, and phosphorous (See Table 6).

After following the procedure, the

supernatant of the soil solution was tested

for its pH level the result was that the soil

had a pH of 8.32. The pH is important

because it influences the availability of

essential nutrients. Most horticultural crops

will grow satisfactorily in soils having a pH

between 6 (slightly acid) and 7.5 (slightly

alkaline).

There are a few plants that require a

soil pH of 4.5 to 5.5. These "acid-loving"

plants include azaleas, rhododendrons, and

blueberries. For most plants, however, a soil

Wc

Wo

Wi

Ignited Soil

Organic Matter

37.62 g 39.12 g 37.38 g 3.76015 g 1.74

Table 5. Amount of soil organic matter

pH below 6.0 is undesirable. Strongly acid

soils need to be limed to raise the pH to near

neutral levels. Liming materials include

ground limestone which is mainly calcium

carbonate (CaCO3) and dolomitic limestone

which contains CaCO3 and some

magnesium carbonate (MgCO3). The soil

pH can also influence plant growth by its

effect on activity of beneficial

microorganisms bacteria that decompose

soil organic matter are hindered in strong

acid soils. This prevents organic matter from

breaking down, resulting in an accumulation

of organic matter and the tie up of nutrients,

particularly nitrogen, that are held in the

organic matter. Inherent factors affecting

soil pH such as climate, mineral content and

soil texture cannot be changed. Natural soil

pH reflects the combined effects of soil-

forming factors (parent material, time, relief

or topography, climate, and organisms). The

pH of newly formed soils is determined by

minerals in the soil’s parent material.

Temperature and rainfall control leaching

intensity and soil mineral weathering. In

warm, humid environments, soil pH

decreases over time in a process called soil

acidification, due to leaching from high

amounts of rainfall. In dry climates,

however, soil weathering and leaching are

less intense and pH can be neutral or

alkaline. Soils with high clay and organic

matter content are more able to resist a drop

or rise in pH (have a greater buffering

capacity) than sandy soils. Although clay

content cannot be modified, organic matter

content can be changed by management.

Sandy soils commonly have low organic

matter content, resulting in a low buffering

capacity, high rates of water percolation and

infiltration making them more vulnerable to

acidification.

The activity levels of decomposing

organisms are greatly impacted by the

amount of water and oxygen present, and

also by the soil temperature. The chemical

makeup of a material, especially the amount

of the element nitrogen present in it, has a

major impact on the ‘digestibility’ of any

material by soil organisms. More nitrogen in

the material will usually result in a faster

rate of decomposition.

Among the area in the Polytechnic

University of The Philippines, Mabini

Campus variations of biota were recognized

(See table 7).

Many studies have shown how both

the living and the non-living environments

affect soil community structure and

diversity, for example, decomposition of

plant litter that is high in lignin and/or low

in nutrients and is therefore difficult to

decompose (resource quality) leads to

dominance by fungal-feeding groups in the

soil food web, whereas, easily broken down

litter is decomposed primarily by bacteria

which is reflected higher up the food chain

(Boyce, 2005). To sum up, decomposition is

affected by the type and quality liter,

climate, the edaphic conditions (including

soil temperature, hydration, and chemistry),

and the community decomposer organism

this is where soil invertebrates fit in (Swift

et. al, 1979).

Soil invertebrates are clearly

affecting liter decomposition rates, soil

Table 6. Soil alkalinity

Test Result Interpretation

Soil pH 8.32 Basic

Soil calcium No precipitate formed No soil calcium

Calcium carbonate Easily heard 10%

Phosphorus Deep blue Presence of phosphorus

in the soil Table 7. Organisms in different soil type

Location Soil Type Organisms

Oval Silt loam Ants (3) Spider (1)

Bug (1) Yellow-Spotted Millipede (1)

Dark Red Millipede (1) Wood louse (1)

Chapel Sandy loam Roaches (4) Red Ants (3)

Gymnasium Clay loam Rusty Millipede (1) Yellow-Spotted Millipede (1)

Common Earth Worm (1) Small Snail (1) Red Ants (2)

Big Black Ant (1) Lagoon Clay loam or sandy loam Large Snails (3)

Small Cone-Shelled Snails (7) Small Six-legged Insects (5)

Linear Loamy sand Roaches (12) Small Cone-Shelled Snails (3) Egyptian Desert Roach (29)

Pill Bug Wood Lice (6) Western Yellow Centipede (3)

Common Earth Worm (1)

aerosion, nutrient mineralization, primary

reproduction, and other ecosystem services

related to soil (Six et al., 2002). They play a

key role by directly consuming detritus,

others consume detritivores, whereas others

are higher-level carnivores that can directly

control decomposition by their effects on

lower levels of the food web (Boyce, 2005).

Conclusion

Edaphic and Climatic Factor turns

out to be a good basis of bigger ecological

applications. Based from the results, it was

clearly illustrated that abiotic and biotic

factors were present in the soil and both are

which affected by each other. Lack of water,

minerals and organic matter, would lead the

soil to be lifeless and would not hold any

inhabitants since they will not have anything

to sustain themselves. Variations of

inhabitants and the soil itself varies from

one point to another by means of need in

that area, soils that have a high water

capacity and nutrient capacity will be

present on areas that has larger scope of life

forms such as crops, trees, and the likes

while soils that have minimal capacity will

be present on areas that are not in need of

high levels of water and nutrient.

Whilst in the Climatic Factor,

although the study focuses more on

microclimate procedures used may be

practiced and can be applied to higher

macroclimate. Climatic Factors such as

aerial temperature, evaporation, humidity,

precipitation and light intensity are factors

that are constantly changing on a day-to-day

basis, analysis of those factors are needed to

identify if the area is amenable to the

organisms present.

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