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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...c7/27/2019 AMALI 1-2
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12.
Rajah 1 : Penyediaan set corong Tulgren 1
Rajah 2 : Penyediaan set corong Tulgren 2 .
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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
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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
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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.
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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.pdfRecommended