Soil PROSES FISIKA BIOLOGI PROSES Biology

11/06/2010 5 IV. Algae minute plants which are photosynthetic found in surface soils but in low amounts Blue green types are important in wet soil –fi...

0 downloads 2 Views 2MB Size
11/06/2010

Soil Fertility

PROSES‐PROSES DALAM TANAH  AKAN SALING TERKAIT PROSES  FISIKA

Soil  Biology

PROSES  BIOLOGI

PROSES  KIMIA

Dwi Priyo Ariyanto Natural Soil Science Department Resources Conservation Service Faculty of Agriculture Helping People Help the Land Sebelas Maret University

ATMOSFER LITOSFER

HIDROSFER BIOSFER

1% nya =

BIOTA TANAH

Soil Organisms ¾ Bacteria

100 million to 1 billion

¾ Fungi

6-9 ft fungal strands put end to end

¾ Protozoa

Several thousand flagellates & amoeba One to several hundred ciliates

¾ Nematodes

10 tto 20 b bacterial t i l ffeeders d and d a few f fungal f l feeders f d

¾ Arthropods

Up to 100

¾ Earthworms

5 or more

Fungsinya

Travis & Gugino PSU

1. Mendekomposisi sisa tumbuhan dan hewan 2 Melepaskan hara dan unsur anorganik 2. yang dibuthkan tanaman dan menyebabkan pelindian mineral 3. Sintesis senyawa organik 4. Formasi humus untuk meningkatkan KPK dan struktur 5. Fiksasi Nitrogen

1

11/06/2010

Soil Organisms Cont.

Flora

Jenis 1. Tumbuhan 2. Hewan

Akar  tanaman  tingkat  tinggi

Ganggang Hijau Hijau‐kebiruan j Diatom

Actino‐ mycetes

Cendawan

Bacteria

Jamur

Aerobic

Ragi

Anaerobic Autotrophic Heterotrophic

Soil Organisms Cont. Tumbuhan (bacteria, actinomycetes, fungi, algae) 1. Bacteria 1 Very small single celled organisms 1. 2. Multiply by elongation and dividing into 2 parts 3. Millions or even billions per gram of soil

a. Non Symbiotic ‐ those that are  free living 1)  Anaerobic organisms ‐ those  not needing free oxygen for  respiration Clostridium –More common in forest soils –Optimum Reaction pH 6.9 ‐ 7.3 –no fixation below pH 5.0

I. Classification of Bacteria (Heterotropic Heterotropic)) A.  Heterotropic memperoleh karbon dan  A.  Heterotropic energi dari variasi senyawa organik 1. Nitrogen fixing mendapatkan nitrogen dalam  1. Nitrogen fixing bentuk gas dari atmosfer atau dari Ammonia  atau Nitrat

2) Aerobic‐ need free oxygen Azotobacter –More common in agriculture  soils –Very sensitive to acidity Very sensitive to acidity –pH below 5.5 to 6.0 no fixation

2

11/06/2010

b.  Symbiotic ‐ live on host plant to mutual advantage Rhizobium ‐ Find on nudules ‐ Nitrogen from the air c.  Aerobic Bacteria‐ requiring combined Nitrogen B ill Bacillus mycoides id ‐ Cause denitrification d. Anaerobic Bacteria ‐ which require combined Nitrogen ‐ Nitrates ‐‐‐‐‐‐‐‐‐‐ Nitrites, ammonia ‐ Sulfates ‐‐‐‐‐‐‐‐‐‐ Sulfites, sulfides

Cont.

B. AutotrophicAutotrophic- derive their carbon primarily from CO2 of the atmosphere and their energy from the oxidation of inorganic compound or simple compounds of carbon

Cont.

1. Bacteria using nitrogen compounds as an energy source a. Nitrosomes - oxidize ammonium Nitrite NH4+ NO2-

SOIL MICROORGANISM

b. Nitrobacter - Oxidize Nitrite to Nitrate NO3- NO2- little or no activity below a pH of 6.0 60 - little or no activity below a temp of 65oF 2. Bacteria using sulfur or sulfur compounds as energy sources. a. Thiobacillus S + O2 + H2O H2SO4

II. Actinomycetes Unicellular micro micro--organisms Transitional between the bacteria and fungi Effect of soil pH

Bacteria

a. Sensitive to acid soilsoil- no activity below pH 5.0, optimum activity between 6.0 - 7.5

UBC EM facility

Pseudomonas

Arthrobacter

Classification of Bacteria (Autotrophic)

CIMC

Bacillus

Ed Basgall Travis & Gugino PSU

Heterotropic FeedersFeeders- breaks down organic matter and humus liberating nutrients, especially nitrogen form NH3

3

11/06/2010

Actinomycetes

Nitrogen Cycle

SSSA

Paul R. August

Univ of Iowa

Streptomyce Travis & Gugino s PSU

III. Fungi

Fungi Cont.

Heterotropic organisms Fungi will tolerate a wide pH range – abundant in acid soils where bacteria and actinomycetes offer only limited competition

Activities of Fungi – Decompose organic residues

– Symbiotic relationship Symbiotic relationship‐‐ help with nutrient  absorption by increasing absorptive surface – Pine seedlings will not grow well without them

Mycorrhizae

Microorganisms Aspergillus

Micorrhiza‐ fungus roots Micorrhiza‐ more common in forest soils ffungal roots form a mat around the  g f absorbing root while others penetrate the  root cells

Fungi

Trichoder ma K.J. KwonChung

PSU Em facility D.C. Straney

Fusarium

Travis & Gugino - PSU

4

11/06/2010

Nematodes

IV. Algae

minute plants which are photosynthetic found in surface soils but in low amounts Blue Blue green types are important in wet  green types are important in wet soil – fix nitrogen in rice paddies – give off oxygen to the water

Natural Soil Mixing (Bioturbation)

Many beneficial effects from activities of microorganisms ‹

Microorganisms produce: – Plant growth g hormones – Stimulate plant growth hormones – Compete with disease organisms

Termites  (rayap) Ants (semut) Earthworms,  cacing tanah

Roots  (akar)

Soil engineering

Mengapa disebut dengan Ecosystem  engineers?  Dapat memperbaiki habitat 

Fungsi Cacing tanah 1. Dekomposer

organisma lain

2. Meningkatkan jumlah pori makro tanah ~ memperbaiki infiltrasi tanah

• meredistribusikan bahan  organik di dalam profil tanah 

3. Bioturbasi

• membatu formasi struktur  tanah Î berpengaruh  langsung terhadap  pertumbuhan tanaman.

Contoh: •Grup Anesik (spesies yang hidup di  permukaan tanah)  •Grup endogeik (spesies yang hidup dan  makan di dalam tanah).

5

11/06/2010

Karakteristik Cacing menurut Fungsinya Karakteristik

Epigeic

Anesic

Endogeic

Lubang

Tidak ada

Terbuka Ektensif dalam permanen ke permukaan tanah

Cast

Tidak ada

Di permukaan Di dlm liang tanah berdekatan atau pori-pori dengan pori tanah tanah

Pigmentasi

Tinggi tkt. samarannya

Sedang, hanya di Tidak bag. belakang berpigmen

Makanan



Makan BO di permukaan dibawa masuk dlm tanah



Dekomposisi BO di permukaan tanah Tidak makan tanah

Lingkungan tanah sehat…. Biota sehat

Mencernak tanah, BO & akar mati

Any  Question?

6