PENGELOLAAN KESUBURAN TANAH RAMAH LINGKUNGAN Oleh: Prof.Dr.Ir.Soemarno,M.S. FP-UB, September 2013 PENGELOLAAN KESUBURAN TANAH RAMAH LINGKUNGAN Oleh: Prof.Dr.Ir.Soemarno,M.S.

Presentasi berjudul: "PENGELOLAAN KESUBURAN TANAH RAMAH LINGKUNGAN Oleh: Prof.Dr.Ir.Soemarno,M.S. FP-UB, September 2013 PENGELOLAAN KESUBURAN TANAH RAMAH LINGKUNGAN Oleh: Prof.Dr.Ir.Soemarno,M.S."— Transcript presentasi:

1 PENGELOLAAN KESUBURAN TANAH RAMAH LINGKUNGAN Oleh: Prof.Dr.Ir.Soemarno,M.S. FP-UB, September 2013 PENGELOLAAN KESUBURAN TANAH RAMAH LINGKUNGAN Oleh: Prof.Dr.Ir.Soemarno,M.S. FP-UB, September 2013

2 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.

3 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.

4 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 berikut 1.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. 1.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 2.penterasan lahan miring (terracering).penterasan bertujuan untuk mengurangi panjang lereng dan memperkecil kemiringan lereng sehingga dapat memperlambat alilan air. 3.pembuatan pematang (guludan)dan saluran air sejajar garis kontur.pembuatan pematangan bertujuan untuk menahan alilan air. 4.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

5 PEMULIHAN KESUBURAN TANAH Diunduh dari: http://www.sciencedirect.com/science/article/pii/S0065211310080041.. 9/9/2012 Chapter Four – Restoring Soil Fertility in Sub-Sahara Africa Mateete 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.

6 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.

7 ISFM: INTEGRATED SOIL FERTILITY MANAGEMENT Diunduh dari: http://www.aglearn.net/isfmMod1.html...... 9/9/2012 Key aspects of the ISFM approach include: 1.Replenishing soil nutrient pools 2.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: 1.Adequate, affordable food, feed and fiber supplies; 2.A profitable system for the producer; and 3.Responsible safeguards for the environment. Sumber: http://www.back-to-basics.net/efu/pdfs/mey.pdf

8 ISFM: INTEGRATED SOIL FERTILITY MANAGEMENT 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)

9 ISFM: INTEGRATED SOIL FERTILITY MANAGEMENT Diunduh dari: http://63.249.122.224/wp-content/uploads/2010/05/unit_1.1_fertility.pdf...... 9/9/2012 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 indicators 1.Soil accepts, holds, releases, and mineralizes nutrients and other chemical constituents 2.Soil accepts, holds, and releases water to plants, streams, and groundwater 3.Soil promotes good root growth and maintains good biotic habitat for soil organisms 4.Soil resists degradation (e.g., erosion, compaction) 5.Soil maintains good soil structure to provide adequate aeration 6.Good soil structure allows for rapid water infiltration 7.Soil has a moderate pH (~6.0–7.0) at which most essential soil nutrients are available 8.Soil has low salinity levels 9.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

10 ISFM: INTEGRATED SOIL FERTILITY MANAGEMENT Diunduh dari: http://63.249.122.224/wp-content/uploads/2010/05/unit_1.1_fertility.pdf...... 9/9/2012 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.

11 ISFM: INTEGRATED SOIL FERTILITY MANAGEMENT Diunduh dari: http://63.249.122.224/wp-content/uploads/2010/05/unit_1.1_fertility.pdf...... 9/9/2012 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.Salinitas rendah: Akumulasi garam dalam tanah dapat menimbulkan gangguan pada tanaman akibat cekaman (stress) air dan garam.

12 ISFM: INTEGRATED SOIL FERTILITY MANAGEMENT Diunduh dari: http://63.249.122.224/wp-content/uploads/2010/05/unit_1.1_fertility.pdf...... 9/9/2012 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.

13 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

14 SOIL FERTILITY MANAGEMENT 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

15 SOIL FERTILITY MANAGEMENT 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

16 LIMA FAKTOR PENGELOLAAN TANAH Pengendalian GULMA. PERGILIRAN TANAMAN (ROTASI TANAMAN) Penyediaan AIR YANG CUKUP Soil moisture management and conservations PENGENDALIAN HAMA & PENYAKIT (INTEGRATED PEST MANAGEMENT) PENYEDIAAN UNSUR HARA INTEGRATED PLANT NUTRIENT MANAGEMENT

17 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

18 POKOK-POKOK PENGELOLAAN KESUBURAN TANAH. 1. Suplai nitrogen dari: Sisa TanamanTanaman biasa Pupuk kandangTanaman legume Hujan & irigasiPupuk hijau Pupuk nitrogenKompos 2. Penambahan bahan organik melalui: Sisa tanaman legume dan non legume Pupuk kandang Pupuk hijau 4. Penambahan fosfat: Pupuk superfosfat, atau Pupuk lainnya 3. Penambahan kapur bila diperlukan Batu kapur kalsit atau dolomit yg biasa dilakukan 7. Penambahan unsur mikro: Sebagai garam terpisah atau campuran 5. Penambahan kalium tersedia: Pupuk kandang Sisa tanaman Pupuk Kalium 6. Kekurangan belerang diatasi dg: Belerang, gipsum, superfosfat, Amonium sulfat, Senyawa belerangdalam air hujan

19 MENGATASI KEKURANG AN NITROGEN Penambahan & Kehilangan N-tersedia N- tersedia dlm tanah Atmosfer Pengikatan Nitrogen Pupuk Buatan SimbiotikNon- Simbiotik Sisa tanaman Pupuk Kandang Bahan Organik Panen Tanaman Hilang Pencucian Hilang Erosi

20 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.

21 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

22 MEMPERTAHANKAN KETERSEDIAAN FOSFAT. Fungsi P sangat penting dalam fisiologi tanaman Kehilangan & Penambahan P-tersedia P-tersedia dalam tanah Sisa tanaman Pukuk kandang Pukuk komersial Mineral P- tanah Bahan Organik Tanah Terangkut tanaman Hilang Pencucian Hilang Erosi Fiksasi

23 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-K lambat tersedia Terangkut tanaman Kehilangan pencucian Kehilangan erosi Kehilangan Fiksasi

24 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 & amoeba One 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.

25 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

26 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

27 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 China Long 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.

28 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 matter Yakov 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).

29 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.

30 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 management 3.It contains bioregulators which affects plant growth 4.It contains bioregulators, which affects plant growth (enzymes, hormones, etc.) 5.Its carbon and energy content is the soil’s energy battery for future use 6.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

31 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 processes 3.Cultivation can have a significant effect on the organic matter content of the soil 4.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 plants Functions 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.

32 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

33 Degradasi: HILANGNYA BOT 1.During field operations, fresh topsoil becomes exposed and dries rapidly on the surface 2.Organic compounds are released to the atmosphere result from breakdown of soil aggregates bound together by humic materials 3.Unless the organic matter is quickly replenished, the system is in a state of degradation leading eventually to un-sustainability 4.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 Chemistry National 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

34 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)).

35 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: OM decomposition rapid in warm climates OM Decomposition is slower for cool regions Under comparable conditions, Av total OM increases as the effective moisture increases. Diunduh dari:...... 10/9/2012

36 Sumber: pgsgrow.com/blog/tag/organic-gardening/ The organic matter in SOIL helps feed all the organisms and release nutrients. 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.

37 Structure of soil, indicating presence of bacteria, inorganic, and organic matter Sumber: www.cartage.org.lb/en/themes/sci...ones.htm The high productivity of most virgin soils has always been associated with their high content of organic matter, and the decrease in the supply with cultivation has generally been paralleled by a corresponding decrease in productivity.

38 PUPUK - PEMUPUKAN Fertilizer is one management option used almost universally Must replace soil nutrients lost by harvest Over-fertilization can result in dangerous pollution Teknologi meningkatkan efisiensi pupuk

39 PENGELOLAAN KESUBURAN TANAH SASARANNYA: –Peningkatan hasil produksi –Reduce costs/unit production –Improve product quality –Avoid environmental pollution –Memperbaiki kesehatan dan estetika lingkungan

40 TUJUAN PENGELOLAAN KESUBURAN TANAH Efficient land managers: spend 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

41 Fertilizers – generally most profitable farm input 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 TUJUAN PENGELOLAAN KESUBURAN TANAH PUPUK – INPUT EKONOMI

42 Utilizing fertilizers may help cut unit cost of production by maximizing yield –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 TUJUAN PENGELOLAAN KESUBURAN TANAH EKOLOGI-EKONOMI PUPUK

43 –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 –Pollute surface waters by runoff –Promotes algae growth in rivers/ponds –Depletes available oxygen in the water for fish TUJUAN PENGELOLAAN KESUBURAN TANAH

44 –Wise use of fertilizers must be encouraged, actually improve the environment Crops, trees, etc. - remove more CO2, decrease sediment, dust, erosion Plays important role for future of the planet TUJUAN PENGELOLAAN KESUBURAN TANAH Diunduh dari:...... 10/9/2012 EKOLOGI PEMUPUKAN

45 PENGELOLAAN LAHAN Pengelolaan Lahan sekala Besar –Medium –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

46 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

47 –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

48 Diunduh dari:.. Pengelolaan sekala Medium : Does improve efficiency of farm inputs Can reduce excessive applications of chemicals/fertilizers May do spot treatments/applications w/in a field due to field observations Small-Scale Management (Precision Farming) Global Positioning System (GPS) – network of U.S. satellites w/ a signal detection system used to locate positions on the ground

49 –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 Diunduh dari:...... 10/9/2012 Precision Farming

50 –Potential to substantially decrease fertilizer/chemical application rates –Potential to substantially decrease input costs –Does require expensive technology, equipment & extensive technical knowledge PENGELOLAAN LAHAN Diunduh dari:...... 10/9/2012 Precision Farming

51 Standard method for determining soil fertility Use of precision farming to minimize inputs Accuracy of soil sample is key!!!! PENGAMBILAN CONTOH TANAH Precision Farming

52 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 PENGAMBILAN CONTOH TANAH

53 Frekuenasi Sampling Tanah: Waktu dan Lokasi –New land, land new to you – yearly for 1 st 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 PENGAMBILAN CONTOH TANAH Diunduh dari:...... 10/9/2012

54 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 PENGAMBILAN CONTOH TANAH Diunduh dari:...... 10/9/2012

55 Uniformity of Sampling Areas –Examine field for differences in soil characteristics, past treatments –Consider: Uniformity of productivity Topography Soil texture Soil structure Drainage Depth/color topsoil Past management PENGAMBILAN CONTOH TANAH Diunduh dari:...... 10/9/2012

56 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) Soil Acidity Evaluation –pH measured w/ electrode & solution –Lime requirement – amount of lime required to achieve desired pH Reported as buffer pH HUKUM MINIMUM

57 UJI TANAH untuk NITROEGEN –No good tests for soil available N –Most states provide N recommendations based on yrs of field plots trials on various crops, soils, management, fertilizers –N recommendations consider:. Tanaman sebelumnya Estimates N carryover N needed to decompose residues Projected yields Climate UJI TANAH = Soil Tests

58 –Lab N tests accurate, but nearly impossible to interpret Some will discourage N testing –Perilaku reqaksi N dalam tanah “unpredictable “– sehingga analisis laboratorium tidak sahih Pencucian N Denitrifikasi Mineralisasi N-organik Pengaruh Iklim UJI TANAH = Soil Tests Diunduh dari:...... 10/9/2012

59 –N recommendations based on yield goals rather than soil reserves –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? UJI TANAH = Soil Tests Diunduh dari:...... 10/9/2012 Rekomendasi pemupukan N

60 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 Most soil P unavailable to crops Soil test extracts & measures what may actually be available UJI TANAH = Soil Tests Diunduh dari:...... 10/9/2012

61 –UJI TANAH untuk K Tests both exchangeable & soluble reserves Conflicting testing procedures over which is most accurate –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, NO 3, PO 4, SO 4 UJI TANAH = Soil Tests

62 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 –Mg testing for: Exchangeable soil Mg % Mg saturation of soil colloids Ratio of K:Mg UJI TANAH = Soil Tests

63 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 = Soil Tests

64 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 UJI TANAH = Soil Tests

65 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 UJI TANAH = Soil Tests

66 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 Diunduh dari:...... 10/9/2012

67 –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

68 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

69 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

70 Kisaran Kritis Kadar Hara (CNR) –CNR – ranges at which nutrients are: Visually deficient Hidden deficient Slightly deficient Sufficient supply Kisaran Toksik ANALISIS TANAMAN

71 –Chlorosis – yellowish to whitish appearance to foliage, stem –Necrosis – dead tissue –Causes: disease, insect damage, salt accumulation, stress, nutrient deficiencies –Beberapa gejala visual “sama” antara gangguan defisiensi dan gangguan penyakit ANALISIS TANAMAN Gejala Defisirensi Hara

72 –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 –Defisiensi hara yang mobil cenderung terjadi pada daun-daun tua ANALISIS TANAMAN

73 –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 –Unsur hara sangat immobile adalah: B, Ca ANALISIS TANAMAN MOBILITAS HARA

74 REKOMENDASI PUPUK Berbagai laboratorium/pakar membuat rekomendasi yang berbeda- beda. Filosofi tradisional menghadapi tantangan: 1.Dosis pupuk P 2.Rekomendasi pupuk N berdasarkan hasil tanaman Diunduh dari:...... 10/9/2012

75 REKOMENDASI PUPUK Diunduh dari: https://www.crops.org/publications/sssaj/articles/74/6/2211...... 11/9/2012 Utilization of Poultry Manure Phosphorus for Corn Production Daniel E. Kaisera, Antonio P. Mallarino and J. E. Sawyer SSSAJ. 2009 Vol. 74 No. 6, p. 2211-2222 Corn plant P concentration (V5–V6 growth stage) response to fertilizer and poultry manure P across seven sites responsive to fertilizer (Table 4). Average total manure P applied across these sites was 55 kg ha−1 for the low rate and 110 kg ha−1 for the high rate. Vertical lines indicate one-half confident intervals (P ≤ 0.10) for means comparisons.

76 –Harus mempunyai cukup banyak data lapangan untuk mengkorelasikan hasil tanaman dnegan kebutuhan haranya –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 Membuat Rekomendasi Pemupukan

77 REKOMENDASI PUPUK Diunduh dari: http://passel.unl.edu/pages/informationmodule.php?idinformationmodule=1130447047&topicorder=2&maxt o=6&minto=1...... 11/9/2012 Yield response as influenced by soil test level and soil test recommendation approach. (Hergert, 1997) The Scientific Basis for Making Fertilizer Recommendations

78 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)

79 Kemasaman Pupuk –Most affect soil acidity in some regard Superphosphate, Triplesuperphosphate, Potash – neutral MAP, DAP, all N fertilizers – acidifiers KUALITAS PUPUK

80 –Fungsi-fungsi: Elemental charge Tendency to form insoluble compounds Adsorption ability Soil texture Water movement Konsentrasi ionm-ion lainnya KUALITAS PUPUK Kelarutan dan Mobilitas dalam Tanah Diunduh dari:...... 10/9/2012

81 –Contoh-contoh Mobilitas hara P hanya dapat bergerak sejauh beberapa sentimeter dalam tanah –Sehingga pupuk P harus ditempatkan di dekat zone akar tanaman N dapat bergerak jauh mengikuti pergerakan air tanah KUALITAS PUPUK Diunduh dari:...... 10/9/2012

82 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

83 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

84 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

85 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 soils Low nutrient levels in the root zone Fast-growing plants Disadvantages: Slows planting Can burn seedling, if placed too close

86 APLIKASI PUPUK Broadcast Application: Pupuk Disebar di permukaan tanah Uniform application across entire surface Left on surface, or incorporated Somewhat less efficiency of fertilizer Especially when not incorporated quickly Why?

87 Alasan Aplikasi pupuk secara disebar: Only practical method of application – pastures, turf, etc. Low-fertility soils needing high fertilizer rates Easy, cheap, personal preference Flexible – split applications, ability to add after crop is growing APLIKASI PUPUK

88 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

89 APLIKASI PUPUK Deep Banding Kerugian: Strong equipment needed High fuel costs Danger of dealing w/ anhydrous Keuntungan: High yield response potential Puts fertilizer where most roots are, very efficient use

90 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

91 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

92 Side-Dressing or Topdressing –Side-dressing – surface or shallow band application put on after crop is growing Broadcast, surface stripped, sprayed, knifed –Principles to consider: Decreases potential N losses Added in the furrow to allow water to help w/ infiltration Not effective for P, K APLIKASI PUPUK

93 Point Injector Application – place P, K into soil in the root zone without significant root damage –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

94 Application of fertilizer with irrigation water –Can apply large quantities of nutrients –Very effective for N Some see 30-50% more efficient use of N Cut of 50% in N rates w/ same/better yield –Must be careful of potential problem with salts APLIKASI PUPUK FERTIGATION

95 –Able to apply when need is highest –Immediate/convenient application –Most effective on soils with poor nutrient retention & for mobile nutrients Chemigation also possible.. ? APLIKASI PUPUK FERTIGATION

96 Aplikasi Daun Foliar Application – foliage wetted to maximize nutrient absorption through leaf stomata & epidermis –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

97 Foliar Application 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) Wind must be calm, humidity >70%, temp <85° F APLIKASI PUPUK

98 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 –Difficult to fertilize due to high nutrient loss risks APLIKASI PUPUK

99 Great focus on increasing efficiency of fertilizer use 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

100 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

101 –Some plants better scavengers than others –Absorption greatly affected by fertilizer distribution –Smaller root system = shorter growing season = >dependence on fertilizer –Growth rates & size also effect amount of nutrients demanded EFISIENSI PUPUK SISTEM AKAR TANAMAN

102 GULMA: –Response to fertilizer much like crops –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

103 1.Availability of nutrients directed impacted by soil water content 2.Drip fertigation may be most efficient use of water & fertilizer Common in greenhouses Can be effective in field use 3. The farming system uses drip irrigation EFISIENSI PUPUK INTERAKSI PUPUK - AIR

104 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 Use starter fertilizer EFISIENSI PUPUK MEMEUPUK SECARA EFISIEN

105 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 Improve management Remember law of minimum Soil test Arahan Pemupukan yang Optimal:

106 Manfaat pupuk kandang: Recycles nutrients Potential to reduce pollution Adds C to soil Improve aggregation, infiltration, microbial vigor Risikonya: Increased weed pressure High cost of obtaining/applying if you don’t own it Not as convenient as commercial fertilizer Pollution anxiety PUPUK KANDANG

107 Nutrient Production & Recovery –Production rates predictable & measurable –Ration has heavy influence on nutrients in manure

108 –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 –Manure still can’t meet plant needs alone Crops remove much higher levels of nutrients/ac PUPUK KANDANG Neraca Hara Ppk Kandang

109 PUPUK KANDANG –Banyak keuntungan menggunakan pupuk kandang –Manure production unevenly distributed in farmland –Biaya angkut tidak murah –Too abundant in areas, not enough land for application Penggunaan Pupuk Kandang

110 –Keseimbangan tiga faktor: Supply crop nutrients Dispose of waste Protect environment –More focus on manure later PUPUK KANDANG Penggunaan Pupuk Kandang

111 PENGELOLAAN KESUBURAN TANAH Oleh: Prof.Dr.Ir.Soemarno,M.S. FP-UB, September 2012 PENGELOLAAN KESUBURAN TANAH Oleh: Prof.Dr.Ir.Soemarno,M.S. FP-UB, September 2012