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IPG Kampus Temenggong Ibrahim

Johor Bahru , Johor.

PROGRAM PENSISWAZAHAN GURU (PPG)

MOD PENDIDIKAN JARAK JAUH

JABATAN SAINS

AMALI 1 :

EKOSISTEM TANAH BIOTA TANAH DAN SIRATAN MAKANAN

NAMA PELAJAR NO. KADPENGENALAN

NO. MATRIK

1. NORIZAT BT JALIL 701224-01-5634 ICSN1106050

2. NOR HIDAYAH BT ESA 731220-01-5132 ICSN1106043

3. NOR KHAIRIAH BT JOHARI 750313-01-6752 ICSN1106044

4. NORSILA BT MOHAMAD 760209-01-6292 ICSN1106052

KUMPULAN/UNIT : PPG-SAINS (KUMP 3)AMBILAN : JUN 2011NAMA MATAPELAJARAN : EKOSISTEM DAN BIODIVERSITIKOD : SCE 3107NAMA PENSYARAH : PN PREMA NAMBIAR

A/P KRISHNANTARIKH HANTAR : 16 FEBRUARI 2013

IJAZAH SARJANA MUDA PERGURUAN

DENGAN KEPUJIAN

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11.

Chong Ngok Mang, Lee Soon Ching & Liew Shee Leong. (1997).Biologi STPM Jilid II.

Shah Alam. Penerbit Fajar Bakti.

Mah Chee Wai. (1987). SPM Biologi Moden. Petaling Jaya. Pustaka Delta.

Safian Sulaiman. (2009). Tanah dan Manusia. Kuala Lumpur. Dewan Bahasa dan Pustaka.

Xiaoyun Chen et.al. Contribution of soil micro-fauna(protozoa and-Academic Diakses

daripada http://www.libra.msra.cn>Publications

Food web Wikipedia, the free encyclopedia Diakses daripada

http://www.en.wikipedia.org/wiki/food-web

Mesofauna (biology) Britannica Online Encyclopedia Diakses daripada

http://www.britannica.com/EBchecked/topic/376735/mesofauna

Mikrofauna (biology) Britannica Online Encyclopedia Diakses daripada

http://www.britannica.com/EBchecked/topic/380375/microfauna

Peran makrofauna dan mikrofauna dalam sifat fisik-Firti05s Blog(2011)Diakses

daripada http://www.firti05.wordpress.com/.../peran-makrofauna-dan-...

Save and grow: 3. Soil Health Diakses daripada

http://www.fao.org>...>1.Thechallenge>2.Farmingsystem

Soil Biota and biodiversity FTP FAO Diakses daripada

http://www.ftp://ftp.fao.org/docrep/fao/010/i0112007.pdf

Soil.net.Com Microfauna and microflora Diakses daripadahttp://www.soil-

net.com/dev/page.cfm?pageid=secondary_intro...c...

RUJUKAN :

http://www.en.wikipedia.org/wiki/food-webhttp://www.en.wikipedia.org/wiki/food-webhttp://www.britannica.com/EBchecked/topic/376735/mesofaunahttp://www.britannica.com/EBchecked/topic/376735/mesofaunahttp://www.britannica.com/EBchecked/topic/380375/microfaunahttp://www.firti05.wordpress.com/.../peran-makrofauna-dan-http://www.ftp//ftp.fao.org/docrep/fao/010/i0112007.pdfhttp://www.soil-net.com/dev/page.cfm?pageid=secondary_intro...chttp://www.soil-net.com/dev/page.cfm?pageid=secondary_intro...chttp://www.soil-net.com/dev/page.cfm?pageid=secondary_intro...chttp://www.en.wikipedia.org/wiki/food-webhttp://www.britannica.com/EBchecked/topic/376735/mesofaunahttp://www.britannica.com/EBchecked/topic/380375/microfaunahttp://www.firti05.wordpress.com/.../peran-makrofauna-dan-http://www.ftp//ftp.fao.org/docrep/fao/010/i0112007.pdfhttp://www.soil-net.com/dev/page.cfm?pageid=secondary_intro...chttp://www.soil-net.com/dev/page.cfm?pageid=secondary_intro...c

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12.

Rajah 1 : Penyediaan set corong Tulgren 1

Rajah 2 : Penyediaan set corong Tulgren 2 .

LAMPIRAN 1 :

LAMPIRAN-LAMPIRAN :

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Rajah 3 : Sampel tanah dari Lokasi 1 dan Lokasi 2.

Rajah 4 : Sampel tanah dimasukkan ke dalam plastik dan dilabel A dan B

Rajah 5 : Gambarajah hasil setelah 48 jam dijalankan.

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Themes:The soil ecosystem | Macrofauna and Mesofauna | Microfauna and Microflora| Quiz

Macrofauna are defined as being larger than 2mm in size.

This group includes larger animals such as badgers, rabbits

and gophers, which all spend a part of their life in the soil, as

well as moles, snails, slugs, earthworms, ants, termites,

millipedes, woodlice, which all spend most of their life in

the soil. Burrowing animals such as earthworms, ants and

millipedes create their own living space by burrowing into

the soil. Creatures such as mites and collembola live in the

existing air spaces in the soil.

Earthworms are very helpful creatures to have in

the soil. They eat plant remains and injest soil

organic matter in various stages of decomposition,

together with microorganisms associated with this

material. They also ingest mineral particles from

the soil and the material they excrete after it has

been digested in their bodies is often well

aggregrated and nutrient rich. They help to produce a good soil structure throughtheir burrowing and casting. They also help to release nutrients and make them

available to growing plants. There are several thousand species of earthworms

worldwide. There are also several thousand species of ants that inhabit the soil.

Some feed on dead organic remains, some are herbivores and a few are predators

on other soil organisms. Like earthworms, ants tend to aerate and mix the soil,

thereby increasing soil drainage.

Mesofauna are 0.1 to 2mm in size. They include arthropods,

such as mites, collembola and enchytraeids. In some soils

these are very abundant. For example, over 200,000

arthropods have been recorded in just a square metre of oldgrassland soils. Some mesofauna feed on bacteria, fungi and

algae, others scavenge on degraded organic matter. They all

contribute to the breakdown of organic matter, stimulation of

microorganisms and deposition of faeces which increase soil

fertility.

Themes:The soil ecosystem | Macrofauna and Mesofauna | Microfauna and Microflora| Quiz

LAMPIRAN 2 :

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Themes:The soil ecosystem | Macrofauna and Mesofauna | Microfauna and Microflora | Quiz

Microfauna are the smallest of the soil fauna and are less

than 0.1 mm in size, and so need a microscope to be seen.

The two most important soil creatures are the nematodes and

the protozoa. Nematodes occur widely in soils, particularly

in sandy soils. They depend on a thin film of water around

particles for their movement. Some species are parasites and

can be a problem for agricultural crops such as potatoes.

Protozoa are small and variable in shape. They are major

consumers of bacteria. They are well suited to life in soilbecause they slide over surfaces relatively easily, feeding on soil particles, roots and thin

water films in the soil.

There are three main forms ofmicroflora in soils: bacteria,

fungi and viruses. Bacteria are tiny organisms composed of

single cells and without a distinct nucleus. They are extremely

numerous in soils with billions in just one gram of soil and

many thousands of species also within a single gram. Bacteria

take part in some of the most important transformations in

soils including weathering of rocks and minerals, breakdown

of organic matter, and many

aspects of nutrient cycling.

Fungi are also very common in soils, taking the form of

spores, globules and filaments. They depend on living and

dead matter in the soil for their carbon and energy. They are

important in the decomposition of organic matter and also

play an important part in stabilising soil aggregates. Very

importantly, mycorrhizal fungi play a major part in securing nutrients for plant production

and many plants are dependent on such relationships.

Viruses are the smallest and simplest multiplying entities in the soil but, perhaps because oftheir small size, rather little is known about them. All are parasites, i.e. they live off other

flora and fauna. A range of plant, insect and human viruses can be found in soils. The

conditions in soils that most influence the numbers of viruses are moisture, the surface of soil

aggregates and structural units and the rooting system of the plants. We know relatively little

about the viruses in soil and also about many of the other tiny organisms. The fact that many

are extremely small and are out of sight below ground means that the full importance of many

of these creatures may yet remain undiscovered for some time.

Themes:The soil ecosystem | Macrofauna and Mesofauna | Microfauna and Microflora | Quiz

LAMPIRAN 3 :

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PERAN MAKROFAUAN DAN MIKROFAUNA DALAM SIFAT FISIK DAN

KIMIA TANAH

A. Peran Makrofauna dalam Sifat Fisik dan Kimia Tanah

Tanah dengan fungsi sebagai habitat beragam jasad hidup, banyak diantara jasad hidup

tersebut belum teridentifikasi. Berbagai spesies biota tanah tersebut bersifat peka terhadap

perubahan lingkungan, praktek pengolahan tanah serta pola tanam sehingga kenekaragaman

biota tanah (mikrofauma, mesofauna, makrofauna) dapat digunakan sebagai petunjuk

terjadinya proses degradasi atau rehabilitasi tanah (Papendick et al, 1992).

Salah satu organisme penghuni tanah yang berperan sangat besar dalam perbaikan kesuburan

tanah adalah fauna tanah. Proses dekomposisi dalam tanah tidak akan mampu berjalan

dengan cepat bila tidak ditunjang oleh kegiatan makrofauna tanah. Makrofauna tanah

mempunyai peranan penting dalam dekomposisi bahan organik tanah dalam penyediaan

unsur hara. Makrofauna akan meremah-remah substansi nabati yang mati, kemudian bahan

tersebut akan dikeluarkan dalam bentuk kotoran.

Keberadaan makrofauna tanah sangat berperan dalam proses yang terjadi dalam tanah

diantaranya proses dekomposisi, aliran karbon, bioturbasi, siklus unsur hara dan agregasi

tanah. Diversitas makrofauna dapat digunakan sebagai bioindikator ketersediaan unsur haradalam tanah. Hal ini karena makrofauna mempunyai peran penting dalam memperbaiki

proses-proses dalam tanah. Sementara itu, setiap organisme mempunyai niche ekologis yang

spesifik, serta nilai baik ekologis, ekonomis, atau estetika.

Diversitas makrofauna yang aktif dipermukaan tanah tidak menunjukkan adanya hubungan

yang nyata dengan parameter ketersediaan unsur hara. Sebaliknya terdapat hubungan yang

nyata antara diversitas makrofauana dalam tanah dengan beberapa sifat tanah (N total,

porositas, dan air tersedia). Tidak adanya hubungan antara diversitas makrofauna yang aktif

di permukaan tanah dengan parameter ketersediaan unsur hara tanah diduga karena

makrofauna yang aktif merupakan fauna asli (natrics) tetapi makrofauna yang keberadaannya

sesaat untuk mencari sumber makanan (fauna exotics) (Maftuah dkk, 2001). Makrofaunayang dapat mempengaruhi sifat fisika tanah diantaranya adalah: semut, rayap, jangkrik dan

cacing tanah.

Semut hewan tanah yang berperan penting dalam perombakan bahan organik. Semut

memakan sisa-sisa organisme yang mati dan membusuk. Pada umumnya perombakan bahan-

bahan organik dalam saluran pencernaan dibantu oleh berbagai enzim pencernaan yang

dihasilkan oleh mesenteron dan organisme yang secara tetap bersimbiosis dengan

pencernaannya.

Semut merupakan makrofauna yang mempunyai peran sebagai pendekomposer bahan

organik, predator, dan hama tanaman. Semut juga dapat berperan sebagai ecosystemengineers yang berperan dalam memperbaiki struktur tanah dan aerasi tanah. Kelimpahan

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semut yang tertinggi biasanya terdapat pada lapisan seresah lebih tinggi. Hal ini dikarenakan

semut lebih menyukai tanah dengan bahan organik yang tinggi dibandingkan dengan bahan

organik yang rendah.

Petal (1998) menyatakan bahwa koloni semut dapat menurunkan berat isi tanah sampai 21-30

% dan kelembaban tanah 2-17 %, serta meningkatkan mikroflora dan aktivitas enzim tanah.Lebih lanjut dijelaskan bahwa pada sarang semut mempunyai kandungan bahan organik

dengan kandungan N total lebih tinggi dibandingkan tanah disekitarnya. Akumulasi bahan

organik dari sisa makanan dan metabolisme akan meningkatkan aktivitas mikroorganisme

dan enzim tanah sehingga pergerakannya akan mempengaruhi struktur dan aerasi tanah.

Kelimpahan rayap juga dapat dipengaruhi oleh kandungan N total tanah dan kelembaban

tanah. Rayap merupakan serangga yang hidupnya berkelompok dengan perkembangan kasta

yang telah diketahui dengan baik kasta reproduktif (ratu) mempunyai tugas menghasilkan

telur dan makannya dilayani oleh rayap pekerja. Rayap merupakan makrofauna tanah yang

penting peranannya pada pembentukan struktur tanah dan pendekomposisian bahan organik

serta ketersediaan unsur hara.

Kelimpahan cacing tanah dipengaruhi oleh bahan organik,dengan meningkatnya bahan

organik maka meningkat pula populasi cacing tanah (Minnich, 1977). Disekitar liang cacing

tanah kaya akan N total dan C organik. Cacing tanah jenispontoscolex corethrurus

mempunyai kemampuan untuk mencerna bahan organik kasar dan mineral tanah halus

(Barois dan Ptron, 1994 dalam Lavelle et all, 1998). Cacing tanah memakan kotoran-kotoran

dari mesofauna di permukaan tanah yang hasil akhirnya akan dikeluarkan dalam bentuk feses

atau kotoran juga yang berperan paling penting dalam meningkatkan kadar biomass dan

kesuburan tanah lapisan atas. Cacing tanah merupakan makrofauana yang berperan dalam

pendekomposer bahan organik, penghasil bahan organik dari kotorannya, memperbaiki

struktur dan aerasi tanah.

Kotoran (feses) cacing tanah mengandung banyak bahan organik yang tinggi, berupa N total

dan nitrat, Ca dan Mg yang bertukar, pH, dan % kejenuhan basa dan kemampuan penukaran

basa. Disini membuktikan bahwa cacing tanah berpengaruh baik terhadap produktivitas

tanah. Karena cacing tanah dalam sifat kimia tanahnya berperan menghasilkan bahan

organik, kemampuan dalam pertukaran kation, unsur P dan K yang tersedia akan meningkat.

Aktivitas dari makrofauna dapat mempengaruhi struktur tanah sehingga dapat memperbaiki

porositas tanah. Makrofauana seperti rayap, semut dan cacing tanah dapat berperan sebagai

ecosystem engineers. Makrofauna tersebut dapat menerima makanan dari tanaman dan akankembali mempengaruhi tanaman melalui perubahan sifat fisik (Lavelle, 1994; Brusaard,

1994).

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microfauna, small, often microscopic animals, especially those inhabiting the soil, an organ,

or other localized habitat. Single-celled protozoans, small nematodes, small unsegmented

worms, and tardigrades (eight-legged arthropods) are the most common components of

microfauna. Many inhabit water films or pore spaces in leaf litter and in the soil, feeding on

smaller microorganisms that decompose organic material.

Lampiran 5

mesofauna, also called Meiofauna, in soil science, intermediate-sized animals

(those greater than 40 microns in length, which is about three times the

thickness of a human hair). Nematodes, mites, springtails, proturans, and

pauropods are typical members of the mesofauna. These animals may feed upon

microorganisms, other soil animals, decaying plant or animal material, living

plants, or fungi. Most mesofauna feed on decaying plant material; by removing

roots they open drainage and aeration channels in the soil. The channels contain

mesofaunal fecal material that can be broken down by smaller organisms.

LAMPIRAN 5 :

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Chapter 3

Soil health

Agriculture must, literally, return to its roots by rediscovering the importance of healthy soil,

drawing on natural sources of plant nutrition, and using mineral fertilizer wisely

Soil is fundamental to crop production. Without soil, no food could be produced on a large

scale, nor would livestock be fed. Because it is finite and fragile, soil is a precious resource

that requires special care from its users. Many of todays soil and crop management systems

are unsustainable. At one extreme, overuse of fertilizer has led, in the European Union, to

nitrogen (N) deposition that threatens the sustainability of an estimated 70 percent of nature 1.

At the other extreme, in most parts of sub-Saharan Africa, the under-use of fertilizer means

that soil nutrients exported with crops are not being replenished, leading to soil degradationand declining yields.

How did the current situation arise? The main driver was the quadrupling of world population

over the past 100 years, which demanded a fundamental change in soil and crop management

in order to produce more food. That was achieved thanks partly to the development and

massive use of mineral fertilizers, especially of nitrogen, since N availability is the most

important determinant of yield in all major crops2-5.

Before the discovery of mineral N fertilizers, it took centuries to build up nitrogen stocks in

the soil6. By contrast, the explosion in food production in Asia during the Green Revolution

was due largely to the intensive use of mineral fertilization, along with improved germplasmand irrigation. World production of mineral fertilizers increased almost 350 percent between

1961 and 2002, from 33 million tonnes to 146 million tonnes7. Over the past 40 years,

mineral fertilizers accounted for an estimated 40 percent of the increase in food production8.

The contribution of fertilizers to food production has also carried significant costs to the

environment. Today, Asia and Europe have the worlds highest rates of mineral fertilizer use

per hectare. They also face the greatest problems of environmental pollution resulting from

excessive fertilizer use, including soil and water acidification, contamination of surface and

groundwater resources, and increased emissions of potent greenhouse gases. The N-uptake

efficiency in China is only about 26-28 percent for rice, wheat and maize and less than 20

percent for vegetable crops9. The remainder is simply lost to the environment.

The impact of mineral fertilizers on the environment is a question of management for

example, how much is applied compared to the amount exported with crops, or the method

and timing of applications. In other words, it is the efficiency of fertilizer use, especially of N

and phosphorus (P), which determines if this aspect of soil management is a boon for crops,

or a negative for the environment.

The challenge, therefore, is to abandon current unsustainable practices and move to land

husbandry that can provide a sound foundation for sustainable crop production

intensification. Far-reaching changes in soil management are called for in many countries.

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The new approaches advocated here build on work undertaken by both FAO10-12 and many

other institutions13-20, and focus on the management of soil health.

Principles of soil health management

Soil health has been defined as: the capacity of soil to function as a living system. Healthysoils maintain a diverse community of soil organisms that help to control plant disease, insect

and weed pests, form beneficial symbiotic associations with plant roots, recycle essential

plant nutrients, improve soil structure with positive repercussions for soil water and nutrient

holding capacity, and ultimately improve crop production21. To that definition, an ecosystem

perspective can be added: A healthy soil does not pollute the environment; rather, it

contributes to mitigating climate change by maintaining or increasing its carbon content.

Soil contains one of the Earths most diverse assemblages of living organisms, intimately

linked via a complex food web. It can be either sick or healthy, depending on how it is

managed. Two crucial characteristics of a healthy soil are the rich diversity of its biota and

the high content of non-living soil organic matter. If the organic matter is increased or

maintained at a satisfactory level for productive crop growth, it can be reasonably assumed

that a soil is healthy. Healthy soil is resilient to outbreaks of soil-borne pests. For example,

the parasitic weed, Striga, is far less of a problem in healthy soils22. Even the damage caused

by pests not found in the soil, such as maize stem borers, is reduced in fertile soils23.

The diversity of soil biota is greater in the tropics than in temperate zones 24. Because the rate

of agricultural intensification in the future will generally be greater in the tropics, agro-

ecosystems there are under particular threat of soil degradation. Any losses of biodiversity

and, ultimately, ecosystem functioning, will affect subsistence farmers in the tropics more

than in other regions, because they rely to a larger extent on these processes and theirservices.

Functional interactions of soil biota with organic and inorganic components, air and water

determine a soils potential to store and release nutrients and water to plants, and to promote

and sustain plant growth. Large reserves of stored nutrients are, in themselves, no guarantee

of high soil fertility or high crop production. As plants take up most of their nutrients in a

water soluble form, nutrient transformation and cycling through processes that may be

biological, chemical or physical in nature are essential. The nutrients need to be transported

to plant roots through free-flowing water. Soil structure is, therefore, another key component

of a healthy soil because it determines a soils water-holding capacity and rooting depth. The

rooting depth may be restricted by physical constraints, such as a high water table, bedrock orother impenetrable layers, as well as by chemical problems such as soil acidity, salinity,

sodality or toxic substances.

A shortage of any one of the 15 nutrients required for plant growth can limit crop yield. To

achieve the higher productivity needed to meet current and future food demand, it is

imperative to ensure their availability in soils and to apply a balanced amount of nutrients

from organic sources and from mineral fertilizers, if required. The timely provision of

micronutrients in fortified fertilizers is a potential source of enhanced crop nutrition where

deficiencies occur.

Nitrogen can also be added to soil by integrating N-fixing legumes and trees into croppingsystems (see also Chapter 2,Farming systems). Because they have deep roots, trees and some

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soil-improving legumes have the capacity to pump up from the subsoil nutrients that would

otherwise never reach crops. Crop nutrition can be enhanced by other biological associations

for example, between crop roots and soil mycorrhizae, which help cassava to capture

phosphorus in depleted soils. Where these ecosystem processes fail to supply sufficient

nutrients for high yields, intensive production will depend on the judicious and efficient

application of mineral fertilizers.

A combination of ecosystem processes and wise use of mineral fertilizers forms the basis of a

sustainable soil health management system that has the capacity to produce higher yields

while using fewer external inputs.

http://www.fao.org/ag/save-and-grow/pdfs/factsheets/en/SG-soil.pdf