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$: Bahan kajian pada MK. MANAJEMEN KESUBURAN TANAH \ PRINSIP-PRINSIP MANAJEMEN KESUBURAN TANAH Diabstraksikan Oleh : Smno.jursntnhfpub.Sept2012$
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KESUBURAN TANAH\

PRINSIP-PRINSIPMANAJEMEN

KESUBURAN TANAH

Diabstraksikan Oleh:Smno.jursntnhfpub.Sept2012

KESUBURAN TANAH

Diunduh dari: http://id.wikipedia.org/wiki/Kesuburan_tanah....9/9/2012

Kesuburan Tanah adalah kemampuan suatu tanah untuk menghasilkan produk

tanaman yang diinginkan, pada lingkungan tempat tanah itu berada. Produk tanaman berupa: buah, biji, daun, bunga, umbi,

getah, eksudat, akar, trubus, batang, biomassa, naungan, penampilan dsb.

Tanah memiliki kesuburan yang berbeda-beda tergantung sejumlah faktor pembentuk tanah yang merajai di lokasi tersebut, yaitu: Bahan induk, Iklim, Relief, Organisme, atau

Waktu.

Tanah merupakan fokus utama dalam pembahasan ilmu kesuburan tanah,

sedangkan kinerja tanaman merupakan indikator utama mutu kesuburan tanah.

CARA MENJAGA KESUBURAN TANAH

Diunduh dari: http://rishadicorp.blogspot.com/2011/03/cara-menjaga-kesuburan-tanah.html..

Untuk menjaga kesuburan tanah bisa dilakukan dengan cara sebagai berikut :

1. Gunakan jerami. Pada tanah sawah, biasanya setelah panen padi kita selalu membuang dan membiarkan jerami ditumpuk di pinggir sawah. Padahal jerami itu bisa kita manfaatkan untuk menyuburkan tanah. Sebarkan jerami tersebut ke lahan dan ratakan. Kemudian taburkan serbuk dolomit ke atas jerami tersebut. Fungsi dolomit untuk membantu mempercepat pelapukan daun jerami dan bisa mengatur tingkat keasaman tanah sehingga tanah bisa lebih matang dan lahan bisa segera ditanami.Setelah sekitar seminggu lahan tersebut bisa langsung dibajak dan jerami yang belum lapuk bisa dibenamkan ke dalam tanah.

2. Lubang resapan Biopori. Pada taman atau halaman rumah bisa kita lakukan metode biopori. Caranya lubangi tanah secara tegak lurus dengan menggunakan pipa besi dengan diameter sekitar 10-20 cm dan kedalaman tanah sekitar 100 cm. Jarak antar lubang resapan biopori adalah 50-100 cm. Kebutuhan jumlah lubang resapan biopori yang diperlukan berdasarkan luas tutupan bangunan. Bila tutupan bangunan dengan luas 20 m2 diperlukan lubang resapan biopori sebanyak 3 unit dan setiap tambahan luas tutupan bangunan 7 m2 diperluhan tambahan 1 unit lubang resapan biopori. Dalam pemeliharaannya lubang resapan biopori ini diisi sampah organik secara berkala dan mengambil sampah tersebut setelah menjadi kompos diperkirakan 2-3 bulan setelah terjadi proses pelapukan.

3. Tanaman Crotalaria.Untuk lahan kritis bisa dimanfaatkan untuk ditanami tanaman crotalaria. Akar tanaman crotalaria bisa mengikat nitrogen dan unsur lain yang sangat dibutuhkan tanah untuk menjadi subur. Daun dan batang tanaman crotalaria sangat baik dijadikan pupuk hijau (kompos) karena mengandung unsur-unsur yang sangat dibutuhkan tanah dan tanaman dibanding pupuk hijau dari tanaman lain.

MENJAGA KESUBURAN TANAH DENGAN CARA METODE VEGETATIF DAN MEKANIK

Diunduh dari: http://lukmanituagam.blogspot.com/2011/03/menjaga-kesuburan-tanah.html..

Upaya yang dapat dilakukan untuk menjaga keseburan tanah sebagai berikut

a. Metode vegetatif dilakukan dengan cara-cara berikut1. penanaman tanaman secara berjalur tegak lulus terhadap arah

aliran(strip cropping).2. penanaman tanaman secara berjalur sejajar garis kontur (contour

strip cropping).3. penutupan lahan yang memiliki lereng curam dengan tanaman

keras (buffering)4. penanaman tanaman secara permanen untuk melindungi tanah dari

tiupan angin (wind breaks).

b.metode mekanik yang umum dilakukan sebagai berikut.5. pengolahan lahan sejajar garis kontur (contour tilage).pengolahan

lahan dengan cara ini bertujuan untuk membuat pola rongga-rongga tanah sejajar kontul dan membentuk igir-igir kecil yang dapat memperlambat alilan air dan memperbesar infiltrasi air

6. penterasan lahan miring (terracering).penterasan bertujuan untuk mengurangi panjang lereng dan memperkecil kemiringan lereng sehingga dapat memperlambat alilan air.

7. pembuatan pematang (guludan)dan saluran air sejajar garis kontur.pembuatan pematangan bertujuan untuk menahan alilan air.

8. pembuatan cekdam.pembuatan cekdam bertujuan untuk memperbendung alilan air yang melewati parit-parit sehingga material tanah hasil erosi yang terangkut aliran tertahan dan terendapkan adannya cekdam menyebabkan erosi tanah dapat dikendalikan,lapisan tanah menebal,dan produktivitas tanah meningkat

PEMULIHAN KESUBURAN TANAH

Diunduh dari: http://www.sciencedirect.com/science/article/pii/S0065211310080041.. 9/9/2012

Restoring Soil Fertility in Sub-Sahara AfricaMateete Bekunda, Nteranya Sanginga, Paul L. Woomer.

Advances in Agronomy. Volume 108, 2010, Pages 183–236

Conceptual diagram of the soil fertility restoration process and the controlling factors.

ISFM: INTEGRATED SOIL FERTILITY MANAGEMENT

Diunduh dari: http://www.aglearn.net/isfmMod1.html ...... 9/9/2012

ISFM : an approach to sustainable and cost-effective management of soil fertility.

ISFM attempts to make the best use of inherent soil nutrient stocks, locally available soil amendments and mineral fertilizers to increase

land productivity while maintaining or enhancing soil fertility.

ISFM is a shift from traditional fertilizer response trials designed to come up with recommendations for simple production increases.

The goal of ISFM is to develop comprehensive solutions that consider such diverse factors as weather, the presence of weeds,

pests and diseases, inherent soil characteristics, history of land use and spatial differences in soil fertility.

It involves a range of soil fertility enhancing methods, such as improved crop management practices, integration of livestock,

measures to control erosion and leaching, and measures to improve soil organic matter maintenance.

ISFM strategies include the combined use of soil amendments, organic materials, and mineral fertilizers to replenish soil nutrient

pools and improve the efficiency of external inputs.


Diunduh dari: http://www.aglearn.net/isfmMod1.html ...... 9/9/2012

Key aspects of the ISFM approach include:

1. Replenishing soil nutrient pools2. Maximizing on-farm recycling of nutrients.3. Reducing nutrient losses to the environment.4. Improving the efficiency of external inputs

ISFM’s basic focus is on sustainability.

The framework of sustainability involves 3 essential components:

5. Adequate, affordable food, feed and fiber supplies; 6. A profitable system for the producer; and 7. Responsible safeguards for the environment.

Sumber: http://www.back-to-basics.net/efu/pdfs/mey.pdf


Diunduh dari: http://63.249.122.224/wp-content/uploads/2010/05/unit_1.1_fertility.pdf...... 9/9/2012

Goals of a Sustainable Soil Fertility Management Program

1. To sustain high crop productivity and crop quality in food and fiber production (not maximum yields, which typically require excessive nutrient inputs to achieve) (a). Crop productivity, crop quality, and the economic viability

of a given farming operation

2. To minimize environmental quality and human health risks associated with agricultural production

a) Important steps in minimizing human health risks and on- and off-farm impacts

i. Avoid the use of all synthetically compounded materials (e.g., fertilizers and pest control agents, etc.) known to have an associated environmental quality or human health risk

ii. Avoid creating non-point source pollution through surface runoff and leaching. Agricultural nutrients can degrade the quality of groundwater or the water in rivers, lakes, wetlands, and estuaries through eutrophication.

iii. Prevent soil erosion and sedimentation of waterways. Soil loss reduces production capacity and soil entering waterways may degrade aquatic habitat.

iv. Close nutrient cycles as much as possible within the field and farm to reduce energy used and environmental impact of food and fiber production

v. Close nutrient cycles at multiple scales (e.g., watershed, regional, and national scales)



Soil fertility: The capacity of a soil to provide nutrients required by plants for growth.

This capacity to provide nutrients to crop plants is in part influenced by the physical properties of soils and is one component of soil

fertility. Desirable soil physical properties and the capacity of the soil to

provide nutrients for growing crops are both soil quality indicators.

Soil quality indicators1. Soil accepts, holds, releases, and mineralizes nutrients and

other chemical constituents2. Soil accepts, holds, and releases water to plants, streams, and

groundwater3. Soil promotes good root growth and maintains good biotic

habitat for soil organisms4. Soil resists degradation (e.g., erosion, compaction)5. Soil maintains good soil structure to provide adequate

aeration6. Good soil structure allows for rapid water infiltration7. Soil has a moderate pH (~6.0–7.0) at which most essential

soil nutrients are available8. Soil has low salinity levels9. Soil has low levels of potentially toxic elements (e.g., boron,

manganese, and aluminum)10. Balanced fertility that provides adequate levels of macro- and

micronutrients that plants and soil microbes require



Components of a Sustainable Soil Fertility Management Program

1. Improve and maintain physical and biological properties of soil

(a) Sustainable agricultural practices used to improve and sustain soil physical and biological properties

1. Maintaining or building soil organic matter (SOM) levels through inputs of compost and cover cropping: SOM has a large capacity to hold and release inorganic (cropavailable) nitrogen and other essential nutrients. Organic matter inputs enhance the stability of soil aggregates, increase the porosity and permeability to water and air, and improve the water-holding capacity of soils. Building or maintaining the level of soil carbon provides the energy and nutrients necessary to stimulate the soil biological activity responsible for decomposition, the formation of soil aggregates, and more desirable soil structure.

2. Properly timed tillage: Stimulates the decomposition of SOM by increasing aeration (O2 supply to aerobic microbes), breaking up compacted areas and large soil clods, and exposing a greater surface area of SOM for microbial breakdown. Appropriate tillage also increases water infiltration and good drainage.

3. Irrigation: For irrigation-dependent crops, manage soil moisture between 50% and 100% of field capacity through soil moisture monitoring and moisture retention techniques such as mulching

4. Use of sound crop rotations, soil amending, and fertilizing techniques all serve to improve the quality of agricultural soils, which in turn affects soil quality and crop performance.



Memperbaiki dan memelihara sifat kimia tanah

(a) Benchmarks of optimal soil chemistry

1. Balanced levels of available plant nutrients (see Unit1.11, Reading and Interpreting Soil Test Reports, for more on this subject)

2. Soil pH ~6.0–7.0: At this soil pH the greatest amount of soil nutrients are available to crops

3. Low salinity levels: The accumulation of salts in the soil may result in plant water and salt stress.



Sustainable agricultural practices used to develop and maintain optimal soil chemical properties

1. Provide a balanced nutrient supply for the crop. As plant growth is related to the availability of the most limiting nutrient, it is essential that we consider the balance (ratios) of soil nutrients available. Yield and quality may be limited if levels of some nutrients are too high while others are too low.

2. Conduct soil analysis with periodic monitoring. Soil analysis provides current quantitative information on the nutrient profile of a given soil. Soil analysis report data should be compared to established optimal benchmarks of soil fertility when developing soil amendment plans to assure adequate but not excessive nutrient applications. Comparing results from multiple years of sampling will show whether you are depleting or accumulating soil nutrients over time, and indicate whether changes in fertility management are needed.

3. Conduct plant tissue testing. In-season plant tissue testing provides current quantitative data on the nutrient profile of growing plants. Such data may be compared with recommended nutrient levels and may be used to determine the need for mid-season supplemental fertilizing. However, be aware that most tissue testing information has been developed for systems using synthetic chemical fertilizers, and sufficiency levels may well differ for organic systems.

SOIL FERTILITY MANAGEMENT

Diunduh dari: http://www.organicagriculture.co/soil-fertility-management.php...... 10/9/2012

Hubungan Tanaman – Tanah dan Lingkungannya

Faktor-faktor yang mempengaruhi kesuburan tanah menjadi fokus pengelolaan kesuburan tanah untuk mendapatkan hasil

yang optimal


Diunduh dari: https://athene.umb.no/emner/pub/EDS215/LectureSoil.htm ...... 10/9/2012

Soil quality is of fundamental importance for agricultural production, and soil fertility management is increasingly becoming a central

issue in the decisions on food security, poverty reduction and environment management.

For the purpose of safe ecological stewardship and achieving global food security, emphasising soil fertility management is becoming

more and more important. The crucial role of soil fertility management for sustainable resource

management and food security has been recognised only quite recently.

Major plant nutrient input and output from agricultural systems


Diunduh dari: http://www.fao.org/docrep/010/ag120e/AG120E10.htm ...... 10/9/2012

Plant nutrient management for improving crop productivity in Nepal Sherchan and K.B. Karki

Soil Science Division, Nepal Agricultural Research Council (NARC)Kathmandu, Nepal

An integrated nutrient model developed quite some time ago as shown below figure was a successful programme but it has not been popularized or has not been well adopted by large number of farmers. There should be a follow up study to see the impact on soil fertility management and to look on how best

we can promote to wider areas.

Integrated plant nutrient components in the Nepalese farming system

LIMA FAKTOR

PENGELOLAAN TANAH Pengendalian GULMA

.

PERGILIRAN TANAMAN(ROTASI TANAMAN)

Penyediaan AIR YANG CUKUPSoil moisture management and conservations

PENGENDALIAN HAMA & PENYAKIT(INTEGRATED PEST MANAGEMENT)

PENYEDIAAN UNSUR HARAINTEGRATED PLANT NUTRIENT

MANAGEMENT

DINAMIKA HARA TANAH

Mempertahankan jumlah optimum unsur hara hanya dapat terlaksana dengan menciptakan keseimbangan yang baik antara penambahan dan

kehilangannya

Benefits of Organic Matter

Increases soil CEC Stabilizes nutrients

Builds soil friability and tilth

Reduces soil splash

Carbon Sequestration

C cycling in agroecosystems has a significant impact at the global scale because agriculture occupies approximately 11%

of the land surface area of the earth.

Benefits of Organic Matter

Reduces compaction and bulk density

Provides a food source for microorganisms

Increases activities of earthworms and other soil critters

POKOK-POKOK PENGELOLAAN

KESUBURAN TANAH.

1. Suplai nitrogen dari:Sisa Tanaman Tanaman biasaPupuk kandang Tanaman legumeHujan & irigasi Pupuk hijauPupuk nitrogen Kompos

2. Penambahan bahan organik melalui:Sisa tanaman legume dan non legumePupuk kandangPupuk hijau

4. Penambahan fosfat:Pupuk

superfosfat, atauPupuk lainnya

3. Penambahan kapur bila diperlukanBatu kapur kalsit atau

dolomit yg biasa dilakukan

7. Penambahan unsur mikro: Sebagai garam terpisah atau campuran

5. Penambahan kalium tersedia:

Pupuk kandangSisa tanamanPupuk Kalium

6. Kekurangan belerang diatasi dg:

Belerang, gipsum, superfosfat, Amonium

sulfat, Senyawa belerangdalam air hujan

MENGATASI KEKURANGAN NITROGEN

Penambahan & Kehilangan N-tersedia

N-tersedia

dlm tanah

Atmosfer

Pengikatan Nitrogen Pupuk

Buatan

Simbiotik Non-Simbiotik

Sisa tanamanPupuk

Kandang

Bahan Organik

Panen Tanaman

Hilang Pencucian

Hilang Erosi

MEMPERTAHANKAN BAHAN ORGANIK

TANAH Carbon Inputs to Soil

Crop residues Cover crops

Compost , and Manures

Carbon Substrate

The majority of C enters the soil in the form of complex organic matter containing highly reduced, polymeric substances.

During decomposition, energy is obtained from oxidation of the C-H bonds in the organic material.

Soil Carbon Equilibrium

Input primarily as plant products Output mediated by activity of decomposers

It is common that from 40 to 60% of the C taken up by microorganisms is immediately released as CO2.

PENTINGNYA Ca & Mg Fungsi fisiologis Ca dan Mg dalam

tanaman

Penambahan dan kehilangan

Ca dan Mg tersedia dalam

tanah

Sisa tanaman &

Pupuk Kandang

Pupuk Komersial

Mineral Tanah

KAPUR

PANEN TANAMAN

Hilang pencucian

Hilang Erosi

MEMPERTAHANKAN KETERSEDIAAN

FOSFAT.Fungsi P sangat penting dalam fisiologi tanaman

Kehilangan & Penambahan P-tersedia

P-tersedia dalam tanah

Sisa tanamanPukuk

kandang

Pukuk komersial

Mineral P-tanah

Bahan Organik Tanah

Terangkut tanaman

Hilang Pencucian

Hilang Erosi Fiksasi

KETERSEDIAAN KALIUM

Tanah mineral umumnya mengandung cukup banyak kalium, kisaran 40 ton setiap hektar lapisan olah tanah. Namun demikian

hanya sebagian kecil yangtersedia bagi tanaman

Kehilangan & Penambahan Kalium:

K-tersedia tanah

Pupuk komersial

Sisa tanaman & Pupuk Kandang

Mineral-Klambat tersedia

Terangkut tanaman

Kehilangan pencucian

Kehilangan erosi

Kehilangan Fiksasi

The Soil Food Web

In 1 teaspoon of soil there are…

5 or more ------------ Earthworms Up to 100 ……………. Arthropods 10 to 20 bacterial feeders and a few fungal feeders ……. Nematodes Several thousand flagellates & amoebaOne to several hundred ciliates ……. Protozoa 6-9 ft fungal strands put end to end ………. Fungi 100 million to 1 billion …………. Bacteria

Diunduh dari: http://soilfoodweb.ca/about_us.html...... 10/9/2012

What is the Soil Foodweb and why is it so Important? The soil foodweb is the tonnes of beneficial bacteria, fungi, protozoa and nematodes that live in soil or compost whose value has been overlooked, undervalued and misunderstood for decades. Recent discoveries in soil

biology show a huge potential to improve current organic, biological and conventional growing and farming and move away from costly synthetic

inputs.

CADANGAN KARBON TANAH

Nonhumic substances—carbohydrates, lipids, proteins

Humic substances—humic acid, fulvic acid, humin

BOT berpengaruh terhadap:

- Hara tanaman- Kesehatan tanah dan

tanaman- sifat-sifat fisika, kimiawi

dan biologis tanah

BOT ----- FRAKSI RINGAN

The light fraction (LF) with a density of ~1.6 gm cm-3 is relatively mineral free and consists of partially decomposed plant material, fine

roots and microbial biomass with a rapid turnover time. The LF is a source of readily mineralizable C and N, accounts for ~50%

of total soil C and declines rapidly under cultivation.

Diunduh dari: https://www.crops.org/publications/sssaj/articles/71/3/1020...... 10/9/2012

Carbon Sequestration and Soil Aggregation in Center-Pivot Irrigated and Dryland Cultivated Farming Systems

Jeroen Gillabel, Karolien Denefb, John Brennerc, Roel Merckxd and Keith Paustian

SSSAJ. Vol. 71 No. 3, p. 1020-1028

BOT --- FRAKSI BERAT --- The Heavy Fraction The heavy fraction (HF) is organic matter adsorbed

onto mineral surfaces and sequestered within organomineral aggregates.

The HF is less sensitive to disturbance an chemically more resistant than the LF.

Diunduh dari: . http://www.sciencedirect.com/science/article/pii/S0038071709004003..... 10/9/2012

Long-term fertilization and manuring effects on physically-separated soil organic matter pools under a wheat–wheat–maize cropping system in an arid

region of ChinaLong Hai, Xiao Gang Li, Feng Min Li, Dong Rang Suo, Georg Guggenberger

Soil Biology and Biochemistry. Volume 42, Issue 2, February 2010, Pages 253–259.

About two thirds of macro OM was actually located within 2–0.05 mm organo-mineral associations or/and aggregates.

Bacteria vs. Fungi Bacteria are smaller than fungi and can occupy smaller pores and thus

potentially have greater access to material contained within these pores. Bacteria are less disrupted than are fungi by tillage practices commonly

used in agriculture.

Diunduh dari: http://www.sciencedirect.com/science/article/pii/S0038071710001355 ...... 10/9/2012

Priming effects: Interactions between living and dead organic matterYakov Kuzyakov

Soil Biology and Biochemistry, Volume 42, Issue 9, September 2010, Pages 1363–1371

PEs (Priming effects) – the interactions between living and dead organic matter – should be incorporated in models of C and N dynamics, and that microbial biomass should regarded

not only as a C pool but also as an active driver of C and N turnover.

Sequence of processes inducing apparent (aPE) and real (rPE) priming effects: 1. Input of available organics by rhizodeposition (Exudation). 2. Activation of microorganisms (mainly r-strategists) by available organics (Activation). 3. Activation of K-strategists. 4. Production of extracellular enzymes that degrade SOM by K-strategists (Enzyme production). 5. SOM decomposition and production of available organics and mineral

nutrients. 6. Uptake of nutrients by roots. The dynamics and sequence of individual processes are described in detail in Blagodatskaya and Kuzyakov (2008).

→ fluxes; — — → effects; ········ dynamics of apparent priming effects (aPEs) and real priming effects (rPEs).

Soil Fungi Fungi tend to be selected for by plant residues with high C/N ratios.

Fungi have a greater influence on decomposition in no-till systems in which surface residues select for organisms that can withstand low water potentials and obtain nutrients from the

underlying soil profile.

Diunduh dari: http://www.sciencedirect.com/science/article/pii/S0038071710003500...... 10/9/2012

Fungi mediate long term sequestration of carbon and nitrogen in soil through their priming effect

S. Fontaine, C. Henault, A. Aamor, N. Bdioui, J.M.G. Bloor, V. Maire, B. Mary, S. Revaillot, P.A. Maron.

Soil Biology and Biochemistry. Volume 43, Issue 1, January 2011, Pages 86–96

Fungi are the predominant actors of cellulose decomposition and induced PE and they adjust their degradation activity to nutrient availability. The predominant role of fungi can be explained by their ability to

grow as mycelium which allows them to explore soil space and mine large reserve of SOM.

The bank mechanism adjusting the sequestration of nutrients and carbon in soil organic matter (SOM) to the availability of nutrients in soil solution tested in this study. This mechanism is based on the assumption that microbial degradation of recalcitrant SOM (priming effect) is modulated by the concentration of nutrients in soil solution . When nutrient availability is low (a), for example because the plant uptake of nutrient is high, the microbial mining of SOM could be intense and eventually exceed the formation of new SOM through

humification of fresh-C, leading to net destruction of SOM and release of mineral nutrients. In contrast, when soluble nutrients are abundant (b), microbial immobilization of N should increase while mining of SOM

should decrease, leading to a greater sequestration of nutrients in SOM. Given that plant demand of mineral nutrients is highly variable and depends on many factors such as plant phenology, soil moisture and light availability, the bank mechanism could help to synchronize the availability of soluble nutrients to plant

uptake. Numbers indicate the chronology of events induced by a change in plant uptake of nutrients.

PENTINGNYA BAHAN ORGANIK TANAH

Bagaimana BOT mempengaruhi hubungan Tanah-Tanaman?

1. Decomposed organic matter provides nutrients for plant growth (Mineralization)2. It determines the soil’s temperature, air ventilation, structure and water management3. It contains bioregulators which affects plant growth4. It contains bioregulators, which affects plant growth (enzymes, hormones, etc.)5. Its carbon and energy content is the soil’s energy battery for future use6. It determines the soil’s capacity to compensating, regenerating and protecting the

environment regenerating and protecting the environment.

Organic matter decomposition and the soil food web

When plant residues are returned to the soil, various organic compounds undergo decomposition. Decomposition is a biological process that includes the physical breakdown and biochemical

transformation of complex organic molecules of dead material into simpler organic and inorganic molecules (Juma, N.G. 1998. The pedosphere and its dynamics: a systems approach to soil science. Volume 1.

Edmonton, Canada, Quality Color Press Inc. 315 pp.)The continual addition of decaying plant residues to the soil surface contributes to the biological activity and the carbon cycling process in the soil. Breakdown of soil organic matter and root growth and decay

also contribute to these processes. Carbon cycling is the continuous transformation of organic and inorganic carbon compounds by plants and micro- and macro-organisms between the soil, plants and the

atmosphere.

Diunduh dari: http://www.fao.org/docrep/009/a0100e/a0100e05.htm...... 10/9/2012

PENTINGNYA BOT

1. Organic material in the soil is essentially derived from residual plant and animal material, synthesised by microbes and decomposed under influence of temperature, moisture and ambient soil conditions

2. Soil organic matter is extremely important in all soil processes3. Cultivation can have a significant effect on the organic matter content of the soil4. In essentially warm and dry areas like Southern Europe, depletion of organic matter

can be rapid because the processes of decomposition are accelerated at high temperatures

5. Generally, plant roots are not sufficiently numerous to replace the organic matter that is lost

Humic substances retain nutrients available on demand for plantsFunctions of humus:

1. improved fertilizer efficiency;2. longlife N - for example, urea performs 60-80 days longer;3. improved nutrient uptake, particularly of P and Ca;4. stimulation of beneficial soil life;5. provides magnified nutrition for reduced disease, insect and frost impact;6. salinity management - humates “buffer” plants from excess sodium;7. organic humates are a catalyst for increasing soil C levels.

Diunduh dari: http://www.fao.org/docrep/009/a0100e/a0100e05.htm#TopOfPage...... 10/9/2012

Humus consists of different humic substances:1. Fulvic acids: the fraction of humus that is soluble in water under all pH conditions. Their

colour is commonly light yellow to yellow-brown.2. Humic acids: the fraction of humus that is soluble in water, except for conditions more acid

than pH 2. Common colours are dark brown to black.3. Humin: the fraction of humus that is not soluble in water at any pH and that cannot be

extracted with a strong base, such as sodium hydroxide (NaOH). Commonly black in colour.

The term acid is used to describe humic materials because humus behaves like weak acids.Fulvic and humic acids are complex mixtures of large molecules. Humic acids are larger than

fulvic acids. Research suggests that the different substances are differentiated from each other on the basis of their water solubility.

Fulvic acids are produced in the earlier stages of humus formation. The relative amounts of humic and fulvic acids in soils vary with soil type and management practices. The humus of forest soils is characterized by a high content of fulvic acids, while the humus of agricultural and grassland

areas contains more humic acids.

MANFAAT BOT

➢ Storehouse for nutrients ➢ Source of fertility ➢ Contributes to soil aeration thereby reducing soil compaction

➢ Important ‘building block’ for the soil structure ➢ Aids formation of stable aggregates ➢ Improves infiltration/permability ➢ Increase in storage capacity for water. ➢ Buffer against rapid changes in soil reaction (pH) ➢ Acts as an energy source for soil micro-organisms

Organic matter within the soil serves several functions. From a practical agricultural standpoint, it is important for two main reasons: (i) as a “revolving nutrient fund”; and

(ii) as an agent to improve soil structure, maintain tilth and minimize erosion.As a revolving nutrient fund, organic matter serves two main functions:1. As soil organic matter is derived mainly from plant residues, it contains all of the

essential plant nutrients. Therefore, accumulated organic matter is a storehouse of plant nutrients.

2. The stable organic fraction (humus) adsorbs and holds nutrients in a plant-available form.

Diunduh dari: http://www.fao.org/docrep/009/a0100e/a0100e04.htm#TopOfPage...... 10/9/2012

Degradasi: HILANGNYA BOT1. During field operations, fresh topsoil becomes exposed and dries rapidly on the

surface2. Organic compounds are released to the atmosphere result from breakdown of soil

aggregates bound together by humic materials3. Unless the organic matter is quickly replenished, the system is in a state of

degradation leading eventually to un-sustainability4. The removal of crop residues in dry ecosystems, which are inherently marginal, can

cause such systems to be quickly transformed from a stage of fragility to total exhaustion and depletion

Selecting Indicators to Evaluate Soil Quality Zueng-Sang Chen

Department of Agricultural ChemistryNational Taiwan University, Taipei, 10617, Taiwan ROC, 1999-08-01

Diunduh dari: http://www.agnet.org/library.php?func=view&style=&type_id=4&id=20110808172707&print=1...... 11/9/2012

Changes in Soil Organic Matter Content (MT/Ha) Calculated in Taiwan under Different Soil Management Systems with Long-Term Application of Composts or

Fertilizers

FAKTOR YG PENGARUHI BOT

Natural factors: ➢ Climate ➢ Soil parent material: acid or alkaline (or even saline) ➢ Land cover and or vegetation type ➢ Topography – slope and aspect

Human-induced factors:➢Land use and farming systems➢Land management (cultivation)➢Land degradation

Potential environmental effects of corn (Zea mays L.) stover removal with emphasis on soil organic matter and erosion

Linda Mann, Virginia Tolbert, Janet Cushman.Agriculture, Ecosystems & Environment. Volume 89, Issue 3, May 2002, Pages 149–

166.

Diunduh dari: http://www.sciencedirect.com/science/article/pii/S0167880901001669 ...... 10/9/2012

Simplified conceptual model of interactions and feedbacks between tillage and soil factors affecting soil organic matter content (adapted from Fig. 2 in Paustian et al.

(1997)).

FAKTOR IKLIM PENGARUHI BOT:

Temperature:OM decomposition rapid in warm climates

OM Decomposition is slower for cool regions

Within zones of uniform moisture and comparable vegetation -- Av total OM increases 2x to 3x for each 10 deg

C fall in mean temperature

Moisture:Dekomposisi BOT berlangsung cepat di iklim hangatDekomposisi BOT berlangsung lambat di iklim dingin

Under comparable conditions , Av total OM increases as the effective moisture increases.

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Sumber: pgsgrow.com/blog/tag/organic-gardening/

Bahan organik dalam tanah membantu menyediakan makanan bagi semua organisme dan pelepasan hara.

Humus acts like glue that holds all the particles together, and it helps prevent erosion and increases a

garden's moisture holding ability. Humus also increases fertility by making nutrients more available to the organic garden plants' roots.

Diunduh dari: http://www.organicgardeninfo.com/soil.ht

ml ...... 11/9/2012

SOIL is Alive!This living-life helps with garden health, fertility,

decomposition of organic matter, replenishment of

nutrients, humus formation, and promotion of root growth, nutrient uptake, and herbicide

and pesticide breakdown.

Structure of soil, indicating presence of bacteria, inorganic, and organic matter

Sumber: www.cartage.org.lb/en/themes/sci...ones.htm

Tingginya kesuburan tanah-0tanah virgin selalu berhubungan dengan tingginya kandungan BOT, dan

penurunan BOT akibat kultivasi biasanya sejalan dengan penurunan produktivitas.

PUPUK - PEMUPUKAN

• Pupuk merupakan satu pilihan pengelolaan yang banyak dilakukan

• Kehilangan hara tanah akibat panen tanaman harus diganti

• Over-fertilization can result in dangerous pollution

• Teknologi meningkatkan efisiensi pupuk

PENGELOLAAN KESUBURAN TANAH

SASARANNYA:– Peningkatan hasil produksi– Reduce costs/unit production– Improve product quality– Avoid environmental pollution

– Memperbaiki kesehatan dan estetika lingkungan

TUJUAN PENGELOLAAN KESUBURAN TANAH

• Efficient land managers: spend <20% of production costs on fertilizers, expect >50% increase in yields

• Pupuk tidak menguntungkan kalau :– Water is the most limiting factor– Other growth hindrances – insects,

diseases, acidity, extreme cold– Increased yield has less market value

than the cost of buying/app of fertilizer

• Pupuk – biasanya merupakan input produksi pertanian yang sangat menguntungkan

• Soil fertility problems usually the easiest to solve

• Soil nutrients typically present in finite amounts, don’t replenish themselves

• Crops typically contain: (in rank of amount found in the plant) N, K, Ca, P, Mg, S


• Pemupukan dapat membantu menutupi biaya produksi dengan jalan memaksimumkan hasil– Improved fertility = improved yields,

improved aesthetic appeal• Environmental concerns abound

– Fertilizer laws viewed as lax by some– Farmers may be the primary cause of

non-point-source pollution


– Bahan polutan :• Nitrat

– Percolate through to groundwater– Not safe to drink– Cause “Blue-baby” syndrome – inhibits

oxygenation of blood– Becoming common near heavily fertilized

fields, feedlots, dairies• Fosfat

– Mencemari perairan permukaan melalui proses runoff

– Promotes algae growth in rivers/ponds– Depletes available oxygen in the water for fish


– Pemupukan secara tepat dan bijaksana dapat memperbaiki lingkungan:

• Crops, trees, etc. - remove more CO2, decrease sediment, dust, erosion

• Plays important role for future of the planet


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PENGELOLAAN LAHAN

• Large- & Medium-Scale Management

– Pengelolaan Sekala Besar• Low levels of operational precision,

little reliance on sophisticated technology

• May be most feasible/profitable for some

• Simple & low-tech• Some shy away from high tech for other

reasons

• Kerugian– Some parts of field may receive too much/little

fertilizer or pesticide– Less than optimal yields– Inefficient use of fertilizers & pesticides– Higher cost of production/unit– Environmental pollution due to over application

• Keuntungan– Minimal technological training & instrumentation

needed– Field operations can be performed w/ standard,

readily available, cheaper equipment.

PENGELOLAAN LAHAN

– Pengelolaan sekala medium• Subdivide field into two+

management units– Delineation may be based on:

» Soil types» Past management differences» Farmer’s observations

• Ex. High, medium, low N application areas in the field

• Same equipment/technology needs as for large-scale management farmers

PENGELOLAAN LAHAN

PENGELOLAAN LAHAN

Diunduh dari: ..

Pengelolaan sekala Medium :Memperbaiki efisiensi input produksi usahatani

Dapat mengurangi aplikasi bahan agrokimia yang berlebihan

May do spot treatments/ applications in a field due to field observations

Small-Scale Management (Precision Farming)

Global Positioning System (GPS) – network of the world satellites , a signal detection system used to locate positions on the ground

– Soil sample fields on a grid– Data collection points no more than a few

feet apart– Each sample site mapped using GPS– Custom applicators can custom apply

fertilizers at variable rates that change constantly as the applicator travels the field – variable rate application, site-specific management, precision farming

PENGELOLAAN LAHAN

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Precision Farming

– Potential to substantially decrease fertilizer/chemical application rates

– Potential to substantially decrease input costs

– Does require expensive technology, equipment & extensive technical knowledge

PENGELOLAAN LAHAN

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Precision Farming

Standard method for determining soil fertility

Use of precision farming to minimize inputs

Accuracy of soil sample is key!!!!

PENGAMBILAN CONTOH TANAH

Precision Farming

Kedalaman dan Banyaknya Sampel Tanah

– Sampling depth – 7-12” for typical soil analysis• Shallower depth for no-till/sod crops

– acid-layer can form at very top of soil structure

• For accurate N analysis – 24-36” depth

– For composite sampling – fewer # samples decreases accuracy of analysis


Frekuenasi Sampling Tanah: Waktu dan Lokasi

– New land, land new to you – yearly for 1st few yrs until you understand the soil

– Every 2-3 yrs, unless concern for environmental problems

– Analysis – determines which nutrients can be made available in the soil & which will need to be supplied

– Samples often pulled in fall to provide enough time for analysis/amendments


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• Spring sampling is more accurate, but conditions may not be favorable, or not sufficient time

– Sampling row crops problematic• Can hit a fertilizer zone• Hard to get enough representative

samples


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• Keseragaman area sampling

– Perbedaan karakteristik tanah dan perlakuan masa lalu

– Memperhatikan:• Keseragaman produktivitas• Topography• Soil texture• Soil structure• Drainage• Depth/color topsoil• Past management


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UJI TANAH = Soil Tests

Law of the Minimum: growth of the plant is limited most by the essential plant nutrient present in the least relative amount (first-limiting)

• Evaluasi kemasaman tanah– pH diukur dnegan elektroda dan

larutan– Kebutuhan kapur – amount of lime

required to achieve desired pH• Reported as buffer pH

HUKUM MINIMUM

• UJI TANAH untuk NITROEGEN– Tidak ada uji yang baik untuk N-tersedia

dalam tanah– Most states provide N recommendations

based on yrs of field plots trials on various crops, soils, management, fertilizers

– Rekomendasi N harus memperhatikan:– Tanaman sebelumnya

• Estimates N carryover• N needed to decompose residues• Proyeksi/ sasaran hasil• Iklim


– Uji N-tanah di laboratorium sangat akurat, tetapi sulit interpretasinya• Some will discourage N testing

– Perilaku reaksi N dalam tanah “unpredictable “– sehingga analisis laboratorium tidak sahih• Pencucian N• Denitrifikasi • Mineralisasi N-organik• Pengaruh Iklim


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– Rekomendasi N berdasarkan pada sasaran hasil, bukan berdasar pada cadangan N dalam tanah

– Corn Rule – ……. kg N/ha of yield goal• How much N should be recommended for

corn following corn, expected yield 2.5 ton/ha?

• How much N should be recommended for corn following soybeans, expected yield 5 ton/ha?


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Rekomendasi pemupukan N

• UJI TANAH untuk P dan K– Widely used to predict probability of crop response

to fertilization

– Survei Tanah:• 47% soil tested medium to low for P• 43% soil tested medium to low for K• P & K soil levels declining in many states

– Uji Tanah untuk P• Quite reliable – soil P is very stable from yr to yr• Kebanyakan P dalam tanah tidak tersedia bagi

tanaman• Uji tanah mengekstraks dan mengukur apa yang

sebenarnya tersedia


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UJI TANAH untuk K

• Uji tanah untuk K-tukar dan K-larut

• Perdebatan prosedur uji tanah, mana yang paling akurat:

– Some estimate upper threshold needs ~159-246 #/ac (above which no response to K fertilizer)

– Others - 335 #/ac on clay soils (calculated based on soil CEC – higher CEC = decreased available K)

– Some experimentation w/ soil probes checking K, NO3, PO4, SO4


• Uji Tanah untuk Ca dan Mg– Related to need for lime– Well-limed soils rarely Ca & Mg

deficient– Mg deficiency more common than Ca

• Coarse-textured or acidic soils• Many yrs using non-Mg containing lime

– Uji tanah untuk Mg :• Mg-tyukar dalam tanah• % kejenuhan Mg pada koloid tanah• Nisbah K:Mg


• Uji Tanah untuk S dan B– S testing inaccurate – acts much like N

• Can test – but must take variability into account

– Rekomendasi kandungan Boron• <1.0 ppm – deficient for plant growth• 1-5.0 ppm – adequate• >5.0 ppm – excess/toxicity risks


UJI TANAH untuk UNSUR MIKRO

– Difficult to develop accurate tests due to relatively infrequent need for field supplementation

– Can be done, if requested for a specific need

– Adds expense to soil analysis


Bagaimana Uji Tanah yang Baik?

– Analyses recalibrated regularly based on field trial studies

– Validity of analysis related directly to accuracy of sample, information provided to the lab.

– Soil analyses generally very valid for: P, K, soluble salts, pH, lime• Other tests should only be used on as-

needed basis– Extra cost– Less accurate


ANALISIS TANAMAN

Evaluasi Ketersediaan hara dalam tanah:

Analisis Tanaman vs. Uji Tanah

– Plant most accurate report on what nutrients are actually available

– Plant analysis leaves little to no room for amendments to the soil

– When deficiencies are acknowledged, yield usually already affected

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– Kapan Analisis Tanaman diperlukan?• Treatment of an easily-corrected deficiency• Long-growing crops: turf, tree fruits, forests, sugar

cane

• Uji Cepat di Lapangan– Can test for N, K status in plants

• Collect ~20 leaves for sample– Must be random from different locations– Don’t select only affected-looking leaves

• Chop/mix, squeeze sap & test• Most effective for greenhouse/nursery growers

– Amendments can easily be made– High possible economic losses

ANALISIS TANAMAN

• Analisis Total Tanaman– Done in a lab– Should be tested by stage of

development– Indicate part of plant sampled & be

consistent – Dry to prevent spoilage (confounds

results)– Wrap in paper and mail w/ complete

report – complete history, information critical

– Random sampling key

ANALISIS TANAMAN

• Interpreting Plant Analyses– Accurate interpretation difficult if not

all critical information provided– Element classified as deficient if below

threshold nutrient levels• Levels change through season, stage of

development, etc.– Some general disagreement from

scientists on what threshold levels are

ANALISIS TANAMAN

INTERPRETASI ANALISIS TANAMAN

• Kisaran Kritis Kadar Hara (CNR)

– CNR – ranges at which nutrients are:• Visually deficient• Hidden deficient• Slightly deficient• Sufficient supply• Toxic

ANALISIS TANAMAN

– Chlorosis – yellowish to whitish appearance to foliage, stem

– Necrosis – dead tissue– Causes: disease, insect damage, salt

accumulation, stress, nutrient deficiencies– Some visual symptoms same for many

diseases/deficiencies

ANALISIS TANAMAN

Gejala Defisirensi Hara

– Nutrients are relocated in the plant by two pathways• Xylem – water-carrying vessels

–All nutrients can pass through• Phloem – sugar-carrying vessels

–Not all nutrients can relocate–Mobile nutrients – travel freely–Immobile nutrients – can’t be

moved from their location in the plant

– Mobile nutrient deficiencies tend to occur on older leaves – plant sacrifices old for new tissue

ANALISIS TANAMAN

– Immobile nutrient deficiencies – symptoms on shoot/root tips, fruits• Can’t be treated from the soil w/

fertilizer – plant can’t send Ca (ex) to the ripening fruit

– Mobile nutrients:• N, P, K, Cl, Mg, S

– Immobile nutrients:• Cu, Mn, Zn, Fe, Mo, S

– Very immobile nutrients:• B, Ca

ANALISIS TANAMAN

MOBILITAS HARA

REKOMENDASI PUPUK

Berbagai laboratorium/pakar membuat rekomendasi yang berbeda-

beda.

Traditional philosophies being challenged:

P application ratesYield-based N recommendations

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Membuat Rekomendasi Pemupukan

– Must have sufficient plot data to correlate yields & nutrient needs

– Once a general amount of fertilizer is known:• Subtract for manure application• Subtract for residual P or N• Add/subtract for N, P, S because of

soil organic matter levels – can count on them supplying some

REKOMENDASI PUPUK

Laporan Uji Tanah

– Labs usually full-service• Soil, plant, manure, irrigation water testing

– See soil test report

REKOMENDASI PUPUK

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KUALITAS PUPUK

GRADE PUPUK – amounts of N, P, K in a fertilizer required by law to be listed

•Also required:–Weight of material, manufacturer

•Optional:–Filler composition, acidity in soil potential

Calculating fertilizer N, P, K amounts•10-20-10•15-12-18

• Amounts listed as: elemental N, phosphate, potash (not direct indication of elemental P, K supplied)

• Acidity & Basicity of Fertilizers– Most affect soil acidity in some

regard• Superphosphate,

Triplesuperphosphate, Potash – neutral

• MAP, DAP, all N fertilizers – acidifiers

KUALITAS PUPUK

– Fungsi-fungsi:• Elemental charge• Tendency to form insoluble compounds• Adsorption ability• Soil texture• Water movement• Concentration of other ions

KUALITAS PUPUK

Kelarutan dan Mobilitas dalam Tanah

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– Contoh-contoh

• P may only move a few cm– Must be place in/near root zone

• N can move w/ extent of water movement

KUALITAS PUPUK

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Calculating Fertilizer Mixtures

– Mixing 34-0-0 ammonium nitrate & 0-46-0 TSP to get 1 ton mixture of 15-10-0• How much of each do we need?

– How about if we needed a 12-14-6 fertilizer for a customer?• What might we use for each ingredient?• How much of each would we need?

PERHITUNGAN PUPUK

Menghitung Campuran Pupuk

• Weights of Fertilizer to Apply

– Planting corn expected to yield 125 bu/ac• How much N do we need?• Soil analysis recommended 88#/ac

phosphate• How much ammonium nitrate & TSP do

we need?• What is our final application rate?

PERHITUNGAN PUPUK

DOSIS PUPUK

Calculations Involving Liquid Fertilizers– Use dry fertilizer calculation if sold

by weight– If sold by volume, usually applied by

volume

PERHITUNGAN PUPUK

DOSIS PUPUK CAIR

APLIKASI PUPUK

Starter (Pop-Up) Fertilizers

Addition of fertilizer w/ the seed during planting, dribbled in a strip near the see, banding w/in 2” of seed

Most beneficial for P, K – some for N, but not as necessary

Advantages:Cold soilsLow nutrient levels in the root zoneFast-growing plants

Disadvantages:Slows plantingCan burn seedling, if placed too close

APLIKASI PUPUK

Broadcast Application

Aplikasi pupuk seragam pada seluruh permukaan lahan

Ditabur di permukaan tanah atau dibenamkan

Somewhat less efficiency of fertilizerEspecially when not incorporated quickly

Why?

Alasan Aplikasi pupuk secara disebar:

• Salah satu metode aplikasi pupuk yang snagat praktis.

• Tanah-tanah yang kesuburannya rendah memerlukan banyak pupuk

• Easy, cheap, personal preference• Flexible – split applications, ability to add

after crop is growing

APLIKASI PUPUK

• Deep Banding– Application of strips into the soil– Either between/side of row, where the seed

may be planted– Typically 4-12” depth– Knifing in anhydrous most common

• Gas able to dissolve in soil water before it escapes

• Losses can be high if dry, sandy

APLIKASI PUPUK

Pupuk dibenamkan secara mendalam

APLIKASI PUPUK

Deep Banding

Kerugian:Strong equipment neededHigh fuel costsDanger of dealing w/ anhydrous

Keuntungan:High yield response potential

Puts fertilizer where most roots are, very efficient use

• Split Application– Divided total fertilizer rates delivered

in 2+ applications– Reasons to split applications

• If large applications are needed – increase efficiency of nutrient use

• Soil conditions dictate – risk for high nutrient losses

• Control vegetative growth in early stages

APLIKASI PUPUK

SPLIT APPLICATION

– Keuntungan:• Increased efficiency of N utilization• Provide a “boost” to the plant during

growth– Kerugian:

• Extra pass through field• Not effective for P, K because of

immobility

APLIKASI PUPUK

• Side-Dressing or Topdressing– Side-dressing – surface or shallow band

application put on after crop is growing• Broadcast, surface stripped, sprayed, knifed

– Prinsip yang harus diperhatikan:• Mengurangi kehilangan N• Ditambahkan dalam larikan untuk membantu

infiltrasi air• Tidak efektif untuk P dan K

APLIKASI PUPUK

Point Injector Application

– Penempatan pupuk P dan K ke dalam tanah di zone perakaran tanpa mengganggu / merusak akar tanaman

– Used more in small plots, gardens– Push stick, rod into soil, fill w/ fertilizer, cover– Effective for: fruit trees, grapes, shrubs, etc.– Not common in field use

APLIKASI PUPUK

Aplikasi pupuk bersama dengan air irigasi

– Dapat mengaplikaiskan sejumlah besar hara

– Sangat efektif untuk N• Some see 30-50% more efficient use of

N• Cut of 50% in N rates w/ same/better

yield– Harus hati-hati terhadap potensial

gangguan garam

APLIKASI PUPUK

FERTIGATION

– Aplikasi dapat dilakukan pada saat kebutuhan hara snagat tinggi

– Aplikasinya mudah dan cepat– Most effective on soils with poor

nutrient retention & for mobile nutrients

Chemigation also possible.. ?

APLIKASI PUPUK

FERTIGATION

Aplikasi DaunFoliar Application

– Daun dibasahi untuk memaksimumkan penyerapan hara melalui stomata dan epidermis daun– Feasible for: N supplementation, pesticides,

micronutrients, etc.– Guidelines:

• Only suited for applications of small amount (can burn plant)

• Decreased rates can be used

APLIKASI PUPUK

Aplikasi Daun

• Need wetting agent to help the spray to distribute evenly across surface

• Helpful when root conditions restrict nutrient uptake

• Quick response/remedy to deficiency (also short residual)

• Angin harus sepoi-poi, lembab nisbi udara >70%, temperatur <85° F

APLIKASI PUPUK

Memupuk padi dan tanah-tanah tergenang lainnya

– Paddy rice – production on water covered soils• Water 2-6” deep• One of very few crops that tolerate

anaerobic conditions

– Sulit memukup karena risiko kehilangan hara sangat besar

APLIKASI PUPUK

Sangat fokus pada peningkatan efisiensi pemupukan

• Research• Real-time sensors in soils that

immediately detect nutrient deficiency• Transgenic plants

Efisiensi Pupuk:

Fraction / percentage of added fertilizer that is actually used by the plant

EFISIENSI PUPUK

Memupuk padi dan tanah-tanah tergenang lainnya

• Efisiensi Pupuk :– 30-70% for N– 5-30% for P– 50-80% for K

• Maximum profits rarely at maximum yields

– Last amounts of fertilizer to produce more yield cost more than yield increase

– Management also key

• Penerapan BMP dapat meningkatkan:– Encourage environmental protection– Couple w/ agronomic success– Increase economic yields, leading to

sustainable ag

EFISIENSI PUPUK

– Some plants better scavengers than others– Absorption greatly affected by fertilizer

distribution– Smaller root system = shorter growing

season = >dependence on fertilizer

– Laju pertumbuhan dan ukuran pertumbuhan juga mempengaruhi jumlah hara yang dibutuhkan

EFISIENSI PUPUK

SISTEM AKAR TANAMAN

GULMA:

– Respons gulma terhadap pupuk sangat serupa dnegan respon tanaman

– N fertilization may increase weed growth > crop growth

– Application method can also affect weed growth• Ex – broadcast fertilizer can tend to help

weeds get good start

EFISIENSI PUPUK

1. Ketersediaan hara tanah ditentukan oleh kandungan lengas tanah

2. Drip fertigation may be most efficient use of water & fertilizer• Common in greenhouses• Can be effective in field use

3. Sistem pertanian menggunakan irigasi tetes

EFISIENSI PUPUK

INTERAKSI PUPUK - AIR

Arahan Pemupukan yang Optimal:

• Avoid large additions of N or K (50#/ac +) on sandy soils – use split application

• Avoid broadcast applications of urea & ammonia on warm/moist soils – volatilizes easily – incorporate

• Avoid N losses on poorly drained soils by using ammonium

• Band P• Menggunakan pupuk “starter”

EFISIENSI PUPUK

MEMUPUK SECARA EFISIEN

EFISIENSI PUPUK

• Keep N & K fertilizers out of seedling zone to avoid burn

• Reduce leaching by avoiding application before rain or irrigation

• Foliar apply, if feasible/appropriate• Know nutrient demands of crop• Memperbaiki pengelolaan• Hukum Minimum• Uji tanah

Arahan Pemupukan yang Optimal:

Manfaat pupuk kandang:• Daur ulang hara• Potential to reduce pollution• Adds C to soil• Improve aggregation, infiltration,

microbial vigorRisikonya:

• Meningkatkan gangguan gulma• High cost of obtaining/applying if you don’t

own it• Not as convenient as commercial fertilizer• Pollution anxiety

PUPUK KANDANG

PUPUK KANDANG

• Produksi dan Recovery Hara– Tingkat Produksi dapat

diralam dan diukur– Ransum sangat berpengaruh

terhadap kandungan hara dalam pupuk kandang

– Generous applications of manure no longer norm• Some states require & enforce strict manure

management guidelines

– Restricted application due to soil P levels instead of N

– Pupuk kandang saja masih belum dapat memenuhi kebutuhan hara tanaman

• Tanaman mengambil lebih banyak hara dari tanah

PUPUK KANDANG

Neraca Hara Ppk Kandang

PUPUK KANDANG

– Banyak manfaat/keuntungan penggunaan pupuk kandang

– Produksi pupuk kandang tidak tersebar merata di seluruh lahan pertanian

– Biaya angkutan pupuk kandang sangat mahal

– Too abundant in areas, not enough land for application

Penggunaan Pupuk Kandang

– Keseimbangan tiga faktor:

• Suplai hara tanaman• Pembuangan limbah• Perlindungan lingkungan

– Lebih fokus pada penggunaan pupuk kandang

PUPUK KANDANG

Penggunaan Pupuk Kandang

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