INDEKS PRODUKTIVITAS LAHAN BAHAN KAJIAN. MK.STELA.SMNO.FPUB.MEI2013
Feb 22, 2016
INDEKS PRODUKTIVITAS
LAHAN
BAHAN KAJIAN. MK.STELA.SMNO.FPUB.MEI2013
PRODUKTIVITAS
Sumber:http://en.wikipedia.org/wiki/Production_%28economics%29
PRODUKSI adalah aktivitas menghasilkan output, barang atau jasa, yang mempunyai nilai dan memberikan utilitas
bagi individu.
The act may or may not include factors of production other than labor. Any effort directed toward the realization of a desired product or service is a "productive" effort and the
performance of such act is production.
Hubungan antara jumlah input yg digunakan dalam produksi dnegan jumlah output yg dihasilkan disebut FUNGSI-
PRODUKSI.
PRODUKTIVITAS
Sumber: http://en.wikipedia.org/wiki/Production_theory_basics
TEORI PRODUKSI merupakan kajian ttg produksi, atau proses ekonomi yg mengkonversi input menjadi output.
Production uses resources to create a good or service that is suitable for use, gift-giving in a gift economy, or exchange in a market economy. This can include manufacturing, storing, shipping, and packaging. Some economists define
production broadly as all economic activity other than consumption. They see every commercial activity other than the final purchase as some form of production.
Production is a process, and as such it occurs through time and space. Because it is a flow concept, production is measured as a “rate of output per period of time”.
Ada tiga aspek penting dalam proses produksi:1. Kuantitas barang atau jasa yg dihasilkan,2. Bentuk barang atau jasa yg dihasilkan,3. Distribusi temporer dan spatial barang atau jasa yg dihasilkan.
A production process can be defined as any activity that increases the similarity between the pattern of demand for goods and services, and the quantity, form, shape, size, length and distribution of these goods and services available to the
market place.
INDEKS PRODUKTIVITAS LAHAN
Sumber:
Faktor ProduksiInput atau sumberdaya yg digunakan dalam proses produksi disebut “faktor
produksi”. Faktor produksi ini biasanya dikelompokkan menjadi lima kategori:1. Bahan mnetah2. Mesin/peralatan produksi3. Tenaga kerja4. Barang kapital5. Lahan.
Dalam jangka panjang “long run”, semua faktor produksi ini dikendalikan oleh manajemen. Akan tetapi dalam jangka pendek “short run”, didefinisikan sebagai periode dimana salah satu
faktor produksi dianggap tetap (fixed).A fixed factor of production is one whose quantity cannot readily be changed. Examples
include major pieces of equipment, suitable factory space, and key managerial personnel.A variable factor of production is one whose usage rate can be changed easily. Examples
include electrical power consumption, transportation services, and most raw material inputs. In the short run, a firm’s “scale of operations” determines the maximum number of outputs
that can be produced. In the long run, there are no scale limitations.
FUNGSI PRODUKSI
Sumber:http://en.wikipedia.org/wiki/Production_function
Fungsi Produksi menghubungkan output-fisik proses produksi dnegan
input-fisik atau faktor produksi. Fungsi produksi merupakan salah satu
konsep kunci dari teori neoklasik mainstream, yg dipakai untuk
mendefinisikan “marginal product” dan membedakan “allocative efficiency” yg
mendefinisikan fokus ekonomi. The primary purpose of the production
function is to address allocative efficiency in the use of factor inputs in
production and the resulting distribution of income to those factors, while
abstracting away from the technological problems of achieving technical
efficiency, as an engineer or professional manager might understand it.
INDEKS PRODUKTIVITAS LAHAN
Sumber:http://en.wikipedia.org/wiki/Production_function
Spesifikasi Fungsi ProduksiFungsi produksi dapat dinyatakan dalam bentuk fungsional sebagai
sisi kanan, dimana: Kuantitas output = F(Kuantitas input),
(kapital, tenagakerja, lahan atau bahan mentah).
If Q is not a matrix (i.e. a scalar, a vector, or even a diagonal matrix), then this form does not encompass joint production, which is a production process
that has multiple co-products. On the other hand, if f maps from Rn to Rk then it is a joint production function expressing the determination of k different types of output based on the joint usage of the specified quantities of the n
inputs.
One formulation, unlikely to be relevant in practice, is as a linear function:where and are parameters that are determined empirically.
INDEKS PRODUKTIVITAS LAHAN
Sumber:
Fungsi kuadratik yang khas ditunjukkan dalam diagram berikut ini mengambil asumsi input tunggal (atau ratio input yang tetap sehingga
dapat dianggap sebagai input tunggal).
All points above the production function are unobtainable with current technology, all points below are technically feasible, and all
points on the function show the maximum quantity of output obtainable at the specified level of usage of the input.
From the origin, through points A, B, and C, the production function is rising beyond point X.
Dari titik A ke titik C, perusahaan mengalami keuntungan marjinal positif yg semakin menurun atas variabel input.
INDEKS PRODUKTIVITAS LAHAN
Sumber:
Stages of production
To simplify the interpretation of a production function, it is common to divide its range into 3 stages. In Stage 1 (from the origin to point B)
the variable input is being used with increasing output per unit, the latter reaching a maximum at point
B (since the average physical product is at its maximum at that
point). Because the output per unit of the variable input is improving throughout stage 1, a price-taking firm will always operate beyond
this stage.
INDEKS PRODUKTIVITAS LAHAN
Foto.smno.saradan.okt2012
‘Economics is the science which studies human behaviour as a relationship
between ends (wants and needs) and scarce means (resources) which have
alternative uses.’Lionel Robbins 1930’s
Faktor-faktor Produksi
11
The ‘scarce means’ in Robbins
definition are the limited resources
available for satisfying ends.
Faktor-faktor ProduksiProposed Minimum Data Set (MDS) of Physical, Chemical, and Biological Indicators for
Screening the Condition, Quality, and Health of Soils
Sumber: http://www.agnet.org/library.php?func=view&id=20110808172707&type_id=4
Resources are said to be scarce or limited relative to the extent
of our wants and
needs.
Faktor-faktor ProduksiSoil Physical Indicators Selected for Assessing the Quality of Taiwan Soils
Sumber: http://www.agnet.org/library.php?func=view&id=20110808172707&type_id=4
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SUMBERDAYA
1. Sumberdaya ekonomi dapat dikelompmokkan menjadi lahan, tenagakerja, kapital dan enterprise.
2. Keempat faktor produksi tersebut seringkali disebut “sumberdaya produksi’.
Lahan didefinisikan sebagai semua
sumberdaya ciptaan Tuhan yang
terlibat dalam proses produksi.
SUMBERDAYA - LAHAN
Sumber: http://www.agnet.org/library.php?func=view&id=20110808172707&type_id=4
Tanah untuk tanaman,
mineral dalam perut bumi,
pohon-pohon, air untuk ikan, transport atau energi, bahkan ikan itu sendiri.
SUMBERDAYA - LAHANAtribut utama penggunaan lahan yg lestari:
1. Menggunakan lahan dengan orientasi jangka panjang;
2. Meeting present needs without jeopardizing future potential;
3. Enhancing per capita productivity;4. Maintaining/enhancing environmental
quality; and5. Restoring productivity and the
environmental regulatory capacity of degraded and impoverished ecosystems.
Sumber: http://archive.unu.edu/unupress/unupbooks/uu27se/uu27se03.htm
Empat kategori sumberdaya ekonomi atau faktor produksi:
1. Land2. Labor3. Capital4. Entrepreneurship
INDEKS PRODUKTIVITAS LAHAN
Sumber: http://www.agecon.purdue.edu/commercialag/progevents/LandValuesWebinar/Farmland_Values_Choices_Web.pdf
Pendekatan Valuasi Lahan PertanianThe traditional income capitalization model provides a straightforward approach with which to view the economic fundamentals of farmland
values. This model simplifies the farmland valuation problem and expresses current farmland values as a function of current income
produced by farmland, the opportunity cost of capital or discount rate, and the constant rate at which income is expected to grow in the
future, as shown below:
Model ini beralasan bahwa peningkatan nilai lahan-pertanian karena ekspektasi peningkatan pendapatan, penurunan suku-bunga, atau
peningkatan laju pertumbuhan pendapatan dari lahan.
Nilah lahan pertanian ditentukan oleh::
1. Produktivitas (supply of crops)
2. Biaya produksi
3. Harga jual hasil tanaman (demand)
4. Interest rates5. Inflation6. Alternative
investments
Soil quality in relation to soil properties, soil processes, and environmental quality
Sumber: http://archive.unu.edu/unupress/unupbooks/uu27se/uu27se03.htm
KUALITASTANAH
Produktivitas tanah
Sumber: http://www.agnet.org/library.php?func=view&id=20110808172707&type_id=4
Penjualan KomparatifFaktor-faktor untuk membandingkan:
1. Produktivitas +2. Lokasion + or -3. Other uses/income + or -4. Family sales -5. Sales contract +6. Akses jalan + or -
Components of a Sustainable Soil Management System.
Sumber: http://www.agnet.org/library.php?func=view&id=20110808172707&type_id=4
Changes in Soil Organic Matter Content (MT/Ha) Calculated in Taiwan under Different Soil Management Systems with Long-Term Application of Composts or
Fertilizers.
Sumber: http://www.agnet.org/library.php?func=view&id=20110808172707&type_id=4
Karakteristik Lahan Pertanian
1. Tidak mengalami depresiasi or wear out2. Suplainya tertentu (fixed)3. Setiap bidang lahan bersifat unik4. Nilainya tgt pada profit dari pertanuan,
penggunaan lainnya5. Kepemilikan menyediakan keamanan ,
pride (kebanggaan, kepuasan)
PRODUKTIVITAS LAHAN
Sumber: http://tax.illinois.gov/publications/pubs/pub-122.pdf
Lahan tanaman termasuk :1. all land from which crops were harvested or hay was cut; 2. all land in orchards, citrus groves, vineyards, and nursery
greenhouse crops; 3. land in rotational pasture, and grazing land that could have been
used for crops without additional improvements; 4. land used for cover crops, legumes, and soil improvement grasses,
but not harvested and not pastured; 5. land on which crops failed; 6. land in cultivated summer fallow; 7. idle cropland.
Cropland is assessed according to the equalized assessed value (EAV) of its adjusted soil productivity index (PI)
PRODUKTIVITAS LAHAN
TINGKAT PENGELOLAAN YANG OPTIMUM
Hasil tanaman yg dihasilkan oleh suatu tanah pd kondisi iklim tertentu tergantung pada input teknologi yg digunakan dan kapasitas tanah
dan tanaman untuk meresponnya. Manajemen merupakan pemilihan dan penerapan teknologi produksi tanaman.
Continuing increases in average crop yields result from improved management. Because the impact of management on crop yields is so
great, the optimum level of management should be defined for measures of soil productivity to have any meaning.
Tingkat optimum pengelolaan termasuk input-input yg dibutuhkan untuk menghasilkan keuntungan-maksimum pada tingkat teknologi
tertentu.
Sumber: http://soilproductivity.nres.illinois.edu/Bulletin811ALL.pdf
Sasarean tingkat pengelolaan optimum
Sumber: http://soilproductivity.nres.illinois.edu/Bulletin811ALL.pdf
Faktor Pengelolaan (faktor Manajemen)
Pengelolaan Optimum
Drainage Parallel or herringbone pattern with closer-than-recommended spacing and adequate outlets
pH tanah at or above 6.2 for grain; at or above 6.9 for alfalfa and clover
P-tersedia (P soil test) based on soil test and depending on phosphorus yield goal, at or above 50 pounds per acre
K-tersedia based on soil test and depending on potassium yield goal, at or above 300 pounds per acre
Dosis pupuk N per tahun untuk tanaman jagung (atau lainnya)
based on soil test and depending on per year for yield goal, at or above 175 pounds per acre.
Populasi jagung 30,000 tanaman per acre, atau lebih
Residu tanaman returned to soil with additional organic materials added as needed
Kontril hama-penyakit-gulma timely using an integrated control pest management approach
Pengolahan tanah dan penanaman
moldboard plow or conservation tillage <2% slopes;conservation tillage including no-tillage for 2% to 10% slopes
Erosi tanah reduced to below soil tolerances using conservation practices as required
PRODUKTIVITAS LAHAN
Sumber:
Indeks Produktivitas Tanaman untuk tanah-tanah pada tingkat pengelolaan yg optimum
Produktivitas tanah snagat dipengaruhi oleh kapasitas tanah untuk mensuplai hara dan air-tersedia yg dibutuhkan tanaman dalam
kondisi iklim tertentu. Productivity also depends in part on the adaptation of a particular crop to specific growing conditions and level of management. It is
often necessary to compare soils that differ in suitability for particular crops or in response to management. Estimated crop yields are not
suitable for these comparisons because yields fluctuate from year to year, and absolute yields mean little when comparing different crops. Indeks produktivitas merupakan sekala tunggal untuk menilai tanah-
tanah berdasarkan kesesuaiannya bagi tanaman pada kondisi pengelolaan tertentu.
KUALITAS TANAH DAN PRODUKTIVITAS
TANAH merupakan suatu entitas fisik dan hidup, tersusun atar batuan-lapuk, senyawa kimia anorganik, biomasa residu tumbuhan dan
binatang, dan beribu organisme hidup. Soil quality has been defined as the sustained capability of a soil to
accept, store, and recycle water, nutrients and energy (Gregorich et al., 1994). In addition, soil quality is the capacity of a soil to sustain
ecological productivity, maintain environmental quality, and promote plant and animal health (Doran & Parkin, 1994).
Selama periode waktu tertentu, tanah mampu menjaga kemampuannya untuk berfungsi sbg komponen hidup dari suatu
ekosistem, tanah dapat mengalami degradasi, atau dapat diperbaiki kualitasnya (Gregorich et al., 1994).
1. Doran, J. & T. Parkin. (1994). “Defining and assessing soil quality.” In: Doran, J., D. Coleman, D. Bezdicek, B. Stewart, (eds) Defining Soil Quality for a Sustainable Environment. SSSA Special Publication 35. Madison WI: Soil Science Society of America: 3-21.
2. Gregorich, E.G., Carter, M.R., Angers, D.A., Monreal, C.M. & Ellert, B.H. (1994). “Towards a minimum data set to assess soil organic matter quality in agricultural soils.” Can. J. Soil Sci. 74, 367-385.Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia
Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS
While production is measured in terms of the yields of crops a particular soil can produce, productivity is its yield per unit of
input, in a given unit of time. Inputs in this case include energy, costs, time, labour, area, nutrients, etc.
Produktivitas seringkali diukur berdasarkan faktor yg paling membatasi atau input yang mahal. Input yg dipilih untuk
menentukan produktivitas harus dilakukan secara eksplisit, karena ia akan berubah menurut pembatas yg ada di lokasi.
Produktivitas ekologis meminimumkan input non-renewable dan output yg mencemari lingkungan, sambil berupaya menjamin
produksi optimum jangka panjang.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS
Produktivitas tanah merupakan suatu fungsi, bukan hanya kualitas tanahnya, tetapi juga beragam faktor lingkungan, seperti iklim dan
topografi. Two soils may have equivalent quality, in terms of the indicators listed in this section, yet one may be less productive than the other. This may
be due to climate. For example, one soil may be located in a cooler location with a shorter growing season. Topography may also limit
productivity.
Tanah-tanah yang kualitasnya sangat baik, mungkin tidak sesuai untuk usahatani karena lerengnya snagat curam. Hal yang sama juga dapat
terjadi untuk tanah-tanah yg kualitasnya bagus dengan pembatasnya berbatu-batuan, drainage, atau bahan induk.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS
Kualitas tanah dan indikator produktivitas tanah :1. Bahan Organik Tanah (BOT) (or soil organic
carbon); 2. Struktur Tanah; 3. Konservasi Tanah4. Jaring-jaring Makanan yang sehat dalam tanah.
Each of these indicators can be tracked over time using a number of different methods.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS
NILAI TANAH
Tanah merupakan aset kapital alami tempat berlangsungnya sistem pertanian. Oleh karena itu untuk menjaga kelestarian
sistem pertanian yg optimal maka TANAH harus dijaga kesehatan dan produktivitasnya.
TANAH dalam sistem produksi pangan biasanya mengalami “undervalued”.
Methods of agriculture that degrade the soil are profitable in the short term under our current system of accounting. This is because the losses of natural capital due to soil erosion or
degradation are invisible in conventional economic accounts, and not included directly in the costs of food production.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS
Degradasi tanah akibat pemadatan-tanah dan kemerosotan kesuburan tanah dapat diimbangi dnegan epeningkatan aplikasi
input produksi seperti pupuk dan bahan bakar.
These inputs can mask the degradation of our soils by allowing crop yields to be sustained and profitable in the short term, at
the expense of long-term productivity.
Ironically, these additional fuel and fertilizer inputs are counted in our conventional measures as contributions to economic growth and ‘prosperity’ even though they may potentially
represent a decline in ecological productivity, and additional costs to the farmer and society.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS
Banyak upaya dilakukan untuk memberikan nilai moneter pada jasa-jasa ekosistem yang dihasilkan oleh tanah-tanah pertanian.
Costanza et al. (1997) menetapkan nilai-nilai untuk lahan pertanian tanaman berdasarkan pada jasa-jasa ekosistem yang dihasilkan oleh
lahan-lahan ini. A higher value was placed on agricultural land that is under grass or
forage, because of the importance of grass and forage in maintaining and protecting soil as a natural capital asset, as emphasized below.
Table 1 shows the ecosystem services provided by these two classes of agricultural land, and the value assigned by Costanza and his
international team of scientists to these lands.
Costanza, R., d’Arge, R., de Groot, R., Farber, S., Grasso, M., Hannon, B., Limburg, K., Naeem, S., O’Neill, R.V., Paruelo, J., Raskin, R.G., Sutton, P., & van den Belt, M. (1997). “The value of the world’s ecosystem services and natural capital.” Nature 387, 253-260.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITASTable 1: Nilai Jasa Ekosistem yg dihasilkan oleh Lahan Pertanian
($1997/ha/yr)
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
Costanza, R., d’Arge, R., de Groot, R., Farber, S., Grasso, M., Hannon, B., Limburg, K., Naeem, S., O’Neill, R.V., Paruelo, J., Raskin, R.G., Sutton, P., & van den Belt, M. (1997). “The value of the world’s ecosystem services and natural capital.” Nature 387, 253-260.
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
BOT merupakan biomasa bangkai tumbuhan dan binatang dalam tanah – seperti residu tumbuhan, rabuk kandanh ternak, dan bangka
serangga – yang tersusun atas unsur karbon.
Most scientific studies report soil organic matter as soil organic carbon (SOC); a factor of 1.7 is used to convert SOC to SOM. Organic matter is
critical for maintaining soil productivity because of the beneficial effects it has on soil moisture, fertility and structure.
It is the most important indicator of soil health and productivity in agricultural systems (Glover et al., 2000).
Glover, J., J. Reganold, & P. Andrews. (2000). “Systematic method for rating soil quality of conventional, organic, and integrated apple orchards in Washington State.” Agriculture Ecosystems and Environment 80, 29-45.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
Memelihara BOT merupakan proses dinamik yg tergantung pada berapa banyak BO ditambahkan ke tanah (sebagai residu tanaman
atau rabuk kandang) dan berapa banyak kehilangan BO (melalui dekomposisi BO atau erosi).
Thus trends are based on net organic matter losses or gains over time. Soil organic matter is decomposed by soil micro-organisms and
provides a source of nutrients for plants. Laju dekomposisi BOT dipengaruhi oleh lengas-tanah, temperature,
tekstur, dan aerasi tanah. Tanah-tanah pertanian dapat mengandung 1 - 10% BO berdasarkan beratnya (Acton and Gregorich, 1995)
tergantung pada lokasi geografisnya dan pengelolaan tanahnya.
Acton, D. & Gregorich, L. eds. (1995). The Health of Our Soils -- Toward sustainable agriculture in Canada. Centre for Land and Biological Resources Research Research Branch Agriculture and Agri-Food Canada Publication 1906/E. Ottawa, Ontario.Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia
Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
Tanah-tanah Podsolik dan tanah-0tanah hutan virgin di Nova Scotia , kandungan BOT nya sekitar 2.8% - 5.8% dalam
lapisan topsoilnya setebal 30 cm.
Cultivation of these soils results in the breakdown of organic matter with declines of 35% of initial soil organic matter reported (Carter et
al. 1998). In some cases growing forage crops on these soils can restore soil
organic matter to levels equivalent to forested sites, or even greater (Carter et al. 1998).
Carter, M.R., Gregorich, E.G., Angers, D.A., Donald, R.G. & Bolinder, M.A. (1998). “Organic C and N storage, and organic fractions, in adjacent cultivated and forested soils of eastern Canada.” Soil Till. Res. 47,253-261.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS
Maintenance of at least 3.8% organic matter (2.2% carbon) has been suggested as a minimum level required for
“moderate structural stability” (Greenland et al., 1975). This level will serve as a goal for sustainable agricultural
production.Humus merupakan BO yang telah diproses oleh organisme
tanah menjadi bentuk yg lebih stabil. Humus berawarna hitam, dan sumber orisinil bahan organik ini tidak mungkin
dapat dikenali kembali secara visual.
1. Greenland, D.J., Rimmer, D. & Payne, D. (1975). “Determination of the structural stability class of English and Welsh soils, using a water coherence test.” J. of Soil Sci. 26, 294-303.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
Pemeliharaan BOT sangat vital bagi produktivitas sistem pertanian jangka panjang karena alasan berikut ini:
1. It is necessary for the formation of stable soil aggregates (see section on Soil Structure) which provide the soil with good aeration, drainage and resistance to erosion and degradation
2. It provides the soil with a negatively charged exchange complex (see box) which prevents leaching of positively charged nutrients into groundwater and holds them in the soil, available for plant use.
3. Organic matter itself is a reservoir of nutrients, particularly nitrogen, phosphorous and sulphur, which become slowly available to crops through processes of biological decomposition (see section on Soil Foodweb).
4. It functions like a sponge to hold water in the soil and release it as needed by crops. This reduces drought-related problems in crops.
5. It is essential as a food source for the many soil microorganisms that provide vital ecosystem services (including pesticide degradation, nutrient cycling, pathogen control, see Soil Foodweb section)
6. It sequesters carbon and can be used to counteract greenhouse gas emissions.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
BOT dibentuk dengan mengembalikan BO ke tanah. Hal ini dapat dilakukan dengan aplikasi rabuk kandang (terutama yang telah masak)
ke lahan, atau mengembalikan residu tanaman ke tanah.
Plants with fibrous root systems, for example ryegrass, hay, or pasture, have immense potential to increase soil organic matter. These crops
are considered soil building because each year their roots produce far more organic matter than is lost through normal SOM decomposition.
Table 2 menyajikan kontribusi residu akar ke tanah setiap tahun, yang secara langsung berhubungan dengan sifat jenis-jenis tanaman ini
dalam membangun karakteristik tanah.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOTTable 2: Estimasi residu biomasa akar yg dihasilkan oleh
jenis-jenis tanaman, PEI
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
BOT dapat rusak dan hilang. Tillage, crop growth, crop harvest, and erosion are several of the loss pathways for organic matter. The cultivation of some
types of crops can have a negative effect on soil quality, by causing net losses of soil organic matter. These potentially soil degrading crops include cultivated row crops such as
corn, beans, potatoes and other vegetables.
The between-row area in row crops is open and cultivated for the first part of the growing season accelerating the
microbial breakdown of soil organic matter.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
BOT didekomposisi oleh Mikroba tanah.
Dekomposisi BOT merupakan bagian dari siklus hara yang menstransfer hara dari bahan organik kepada tanaman (proses ini
disebut MINERALISASI). Akan tetapi, kalau perombakan BO melampaui akumulasinya dalam jangka panjang, maka kandungan
BOT akan menurun.
The process of organic matter breakdown speeds up when air is mixed with the soil during cultivation.
The tillage associated with growing annual crops is generally depleting to soil organic matter.
Growing hay crops for several years in a row without tillage will help to re-build soil organic matter levels.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOTTable 4: BOT: Measures, Objectives, Results
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
NILAI BOTEstimasi total nilai semua jasa-jasa ekosistem yg dihasilkan oleh BOT tidak mudah diestimasi, tetapi dapat diestimasi kontribusi tahunan
(musiman) hara-tersedia bagi tanaman. Carter et al. (1998) report an average soil nitrogen (N) content of 5,800 kg/ha for
cultivated Podzols (the predominant soil type in Nova Scotia). Although some of that nitrogen exists in the inorganic (nitrate, ammonium, and amino acid) form, the
majority of soil N is tied up in soil organic matter. This nitrogen is released to the growing crop through the process of mineralization.
Moncayo (1992) estimated the annual contribution of organic N mineralization in Nova Scotia to be 1.5% of the total soil N content. Using this factor, we can estimate
an annual contribution of N from soil organic matter of 87 kg N/ha. Fertilizer N is currently worth almost $1/kg.
Therefore organic matter is contributing $82/ha/yr worth of nitrogen. The reservoir (stock) of soil organic N on farmed land is worth more than $5,400/ha ($945 million
provincially).
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
NILAI BOT
BOT juga mensuplai sejumlah hara P bagi tanaman. Kandungan P BOT diperkirakan sepersepuluh (0.10) kandungan N nya (Tisdale et al.
1985). Maka dapat dihitung kontribusi musiman P ke lahan pertanian sebesar 21 kg P2O5 /ha.
Fertilizer P is worth about $1/kg P2O5, so the value of phosphorus supplied by organic matter is approximately $20/ha annually or $3.5 million province-wide. Because this remarkable contribution is provided ‘freely’ by nature, it appears
nowhere in standard accounting systems.
And when farmland is managed so that soil organic matter is lost, this loss of value also remains invisible. Ironically, the cost to the farmer of replacing this lost asset through synthetic fertilizer is then counted as a contribution to general economic
prosperity, simply because the exchange of money now enters the economy.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
KEHILANGAN BOT
Farmers on the monoculture potato fields will be spending approximately $10/ha/yr more than the farmers using potato-grass rotations to supply the N and P that could
have been provided by the lost soil organic matter. If the farmers using rotations switched to a leguminous forage crop (which ‘fixes’
atmospheric nitrogen and adds it to the soil), they could expect to spend up to $114/ha/yr less than the monoculture potato farmers in the year after plowdown, to
meet their potato crop’s N needs.This 0.5% loss of soil organic matter represents a decrease in stock value (based only
on N and P fertilizer value) of $650/ha.Kehilangan kapital alam ini dapat dipulihkan kembali kalau pertanian monokultur diubah menjadi sistem rotasi tanaman , misalnya forage-
potato. We can expect a new, higher soil organic matter equilibrium level to be reached after about twenty years, the amount of time it would take to
increase soil organic matter by 0.5%.Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia
Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOTTable 5: A comparison of revenues and expenses, continuous corn vs. corn/hay rotation
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: BOT
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: STRUKTUR TANAH
Soil structure is defined as the physical properties of a soil relating to the arrangement and stability of soil particles and pores (McBride et al., 2000). Structure is a qualitative characteristic of soil. We can describe a soil with ‘good’ structure as being friable, light, and workable, with good tilth. Soil
aggregation is a component of soil structure. This is the arrangement of soil particles in granules or crumbs which are held together by organic
compounds known as polysaccharides (complex sugars). Suatu tanah yang struktur dan agregasinya baik mempunyai :
1. Ruang porinya banyak2. Aerasi dan drainagenya bagus3. Daya simpan airnya bagus4. Penetrasi akarnya lebih baik5. Sedikit energi untuk pengolahan tanah6. Tahan terhadap gaya-gaya erosi.
1. McBride, R.A., Joosse, P.J. & Wall, G. (2000). Risk of Soil Compaction in Agriculture and Agri-Food Canada. Environmental Sustainability of Canadian Agriculture: Report of the Agri-Environmental Indicator Project. T. McRae, C.A.S. Smith, & L.J. Gregorich (eds). Agriculture and Agri-Food Canada, Ottawa.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: STRUKTUR TANAH
Compaction can be defined as a process by which external forces compress the soil, making it more dense, less porous, and less capable
of performing the functions just listed (Moerman, 1994).
Soil compaction caused by wheel traffic and tillage is one form of soil degradation. This process leaves the soil denser, less permeable to air and water, slower to warm up in the spring, more difficult to till, and
more resistant to the penetration of plant roots. Reduced efficiency of nutrient uptake results in impeded plant growth.
Pemadatan tanah merupakan masalah serius pada tanah-tanah yang teksturnya halus.
Moerman, D. (1994). “Soil compaction: avoiding and fixing a widespread problem,” in Proceedings Nutrient Management on the Farm: A Conference for Maritime Farmers. Kentville, Nova Scotia, February 8-9, 1994, NSDAM and Agriculture Canada.Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia
Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: STRUKTUR TANAH
Mengukur Struktur Tanah
Struktur tanah dievaluasi dengan jalan menilai derajat pemadatan (diukur dnegan bobot isi tanah), kandungan BOT, tipe tanaman, dan
tipe/jumlah pengolahan tanah. Umumnya, tanah-tanah yang BI nya rendah mempunyai struktur yang
lebih baik. Bobot isi yang tinggi dan resistensi penetrometer merupakan indikasi dari strultur tanah yang jelek, dan pemadatan
tanah yang tinggi (McBride et al., 2000). Fine- textured soils are most prone to soil compaction. The structure of these soils is easily destroyed by excessive tillage, especially when
the soil is cultivated during wet periods.
McBride, R.A., Joosse, P.J. & Wall, G. (2000). Risk of Soil Compaction in Agriculture and Agri-Food Canada. Environmental Sustainability of Canadian Agriculture: Report of the Agri-Environmental Indicator Project. T. McRae, C.A.S. Smith, & L.J. Gregorich (eds). Agriculture and Agri-Food Canada, Ottawa.Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia
Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: STRUKTUR TANAH
BOBOT ISI (BI) TAMAH
BI merupakan ukuran fisik yg dipakai untuk mendeskripsikan tanah-tanah. BI tanah dapat dihitung dengan jalan membagi berat-kering-oven tanah dengan
volumenya. Biasanya BI tanah dinyatakan dnegan satuan g/cm3 atau kg/m3.
Typical bulk densities in agricultural soils range from 1.1 to 1.7 g/cm3 depending on various factors including texture, organic matter content, and soil management practices.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: STRUKTUR TANAH
Strabilitas agregat tanah dan bobot isi tanah merupakan dua indikator penting bagi struktur tanah (Glover et al., 2000). Aggregat adalah struktur,
atau gumpalan, yang dibentuk kalau mineral tanah dan bahan organik berikatan (bergabung) bersama dengan bantuan (sebagai perekatnya)
molekul organik , akar tanaman, fungi, dan liat (Magdoff & van Es, 2000). The strength of the soil aggregates (granules or crumbs) will determine the soil’s resistance to compaction. This ‘aggregate stability’ has been strongly
correlated with soil organic matter content (Glover et al., 2000).Bobot isi tanah dan stabilitas agregat tidak diukur untuk keseluruhan lahan
usahatani, sehingga diperlukan cara lain untuk menduga struktur tanah.
1. Glover, J., J. Reganold, & P. Andrews. (2000). “Systematic method for rating soil quality of conventional, organic, and integrated apple orchards in Washington State.” Agriculture Ecosystems and Environment 80, 29-45.
2. Magdoff, F., & van Es, H. (2000). Building Soils for Better Crops. Second Edition. Beltsville MD: Sustainable Agriculture Network.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: STRUKTUR TANAH
Compaction can be reduced by certain soil management practices. Methods that return organic matter to the soil will improve soil structure, result in better soil aggregate formation, and reduce
compaction. Metode-metode ini meliputi:
1. Penambahan rabuk kandang dan kompos ke tganah2. Pergiliran tanaman yg melibatkan tanaman berakar-dalam, yang
residu biomasanya meningkatkan BOT, akarnya dapat memecah lapisan-tanah subsoil padat. Angers et al. (1987) melaporkan perbaikan kekuatan agregat tanah dan porositas antar agregat setelah dua tahun penanaman “bromegrass” mengikuti 12 tahun penanaman jagung monokultur.
Angers, D.A., Kay, B.D., & Groenvelt, P.H. (1987). “Compaction characteristics of a soil cropped to corn and bromegrass.” Soil Sci. Soc. Amer. J. 51,779-783.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: STRUKTUR TANAH
Since excessive wheel traffic contributes to soil compaction, farming practices which minimize the number of trips the farmer must make
around the field should also reduce soil compaction.Metode-metode ini meliputi:
1. Olah tanah minimum; misalnya memakai “bajak chisel” yg memecahkan cadas-cadas keras dan meninggalkan residu biomasa tanaman di permukaan tanah
2. Meminimumkan olah tanah sebelum tanam, untuk mengurangi efek langsung peralatan olah-tanah thd pemadatan tanah dan meminimumkan kerusakan struktur tanah akibat pengolahan tanah
3. Integrated pest management (IPM) strategies for pest control so that trips over the field with spray equipment are kept to a minimum.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: STRUKTUR TANAH
Large loads and high surface pressure from wheel traffic in the field also contribute to compaction.
Petani dapat mereduksi efek pemadatan tanah oleh alat-mesin pengolahan tanahnya dengan menggunakan sistem yg
efek tekanan-tanahnya minimum.
Hal ini melibatkan pemilihan peralatan yang :1. uses dual or flotation tires which spread the load, thereby reducing
the pressure per square inch of soil;2. has more axles, thereby distributing the load over more wheels;
and3. Bobotnya ringan, sehingga mereduksi “tekanan” terhadap tanah.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: STRUKTUR TANAH
Table 7: Metode-metode untuk Menduga Struktur Tanah
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: STRUKTUR TANAH
Table 9: Nilai Struktur Tanah
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: EROSI TANAH
Techniques of soil management that minimize the risk of soil loss due to wind and water erosion are known as soil conservation practices. Erosion rates in excess of the natural rate of regeneration (1 cm in 120 to 400 years) reflect a gradual loss of value in farmland.30 This loss can be expressed conservatively as 1 tonne per ha per year.
Erosion has serious implications for soil quality and productivity. Nutrients and organic matter are lost when soil is eroded from a field. The soil’s structure is
weakened and general soil degradation results, producing losses in crop productivity. Tillage operations can be impeded by erosional gullies, and energy
expended can increase due to exposure of compact subsoil.
Off-site damage also results from soil erosion. In streams and rivers, water turbidity and sedimentation increase. The nutrients, pesticides, and bacteria that can be
bound to the eroded soil particles can have a detrimental effect on fish and wildlife health. And the recreational value of fresh and salt water can be reduced due to a
decline in aesthetic quality.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: EROSI TANAH
Strategi mengurangi erosi tanah:
Memelihara dan Memperbaiki Kandungan BOT
Soil organic matter is vital for the formation of stable soil aggregates (see discussions of soil organic matter and structure above).
Plant roots and microbes produce mucilage, which in effect ‘glues’ together soil mineral and organic particles. The resulting improvement in soil structure decreases
the soil’s erodibility. Erodibility is the soil’s susceptibility to detachment and transport by erosive agents
(ECSWCC, 1993). Pergiliran tanaman dan aplkikasi pupuk kandang dapat meningkatkan
kandungan BOT.
1. Eastern Canada Soil and Water Conservation Centre. (1993). “Crop Rotation Systems for Potato Production in Atlantic Canada.”
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: EROSI TANAH
Strategi mengurangi erosi tanah:
Pengelolaan Residu sisa panenManagement practices which leave 30% of crop residue or more on
the soil surface reduce soil erosion by obstructing overland flow, reducing the velocity of the runoff, and increasing water infiltration
into the soil.
Strip-cropping dan Terrasering. Penanaman lahan menurut garus kontur di lapangan, dan bukan tegak lurus garis kontur, dapat mengurangi erosi tanah sebesar 75% (DeHaan
1994).
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: EROSI TANAH
Strategi mengurangi erosi tanah:
Vegetasi Penutup Muka Lahan.
Penanaman jenis-jenis tanaman yang secara khusus untuk menutup muka tanah selama periode risiko erosi tinggi – (misalnya di lokasi
Prince Edward Island 85% erosi terjadi selama periode antara October dan akhir April) – dapat mereduksi kehilangan tanah secara signifikan.
Edwards and Barney (1987) report a reduction in soil loss of 1.8 t/ha (0.36 t/ha versus 2.16 t/ha) when soil loss from a
cover crop of winter rye was compared to bare soil.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: EROSI TANAH
MENGUKUR KEHILANGAN TANAH & KONSERVASI
The Universal Soil Loss Equation (USLE)
If annual soil loss could be measured, it would be a direct way to assess the status of soil conservation in the province:
As soil losses from agricultural land decrease, soil conservation, as a component of soil quality, would improve.
Soil losses on agricultural land can be estimated using the Revised Universal Soil Loss Equation (RUSLE) (see box).
VegetaSI PENUTUP TANAH (C) and soil management (P) are the two components of the RUSLE over which the farmer has control.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: EROSI TANAH
The Universal Soil Loss Equation (USLE), A=RKLSCP, computes annual soil loss as a function of rainfall (R), soil erodibility
(K), slope length (L), slope gradient (S), vegetative cover (C), and soil management (P).
It can be used to estimate soil losses for a given piece of land under different management systems.
The Revised USLE was released in 1992 with refined factor values generated from improved data and computer
modeling.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: EROSI TANAHTable 13: Metode untuk menilai erosi tanah dan konservasi
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: EROSI TANAHTable 14: Produktivitas relatif (%) tanaman yang dipengaruhi oleh kehilangan tanah
akibat erosi, Nova Scotia
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: EROSI TANAHTable 18: Nilai Konservasi Tanah
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
Soil foodweb analysis has been proposed as an indicator of soil quality. The soil foodweb is the complex mixture of bacteria, fungi, protozoa,
nematodes and microarthropods, which control the cycling of nutrients within an ecosystem.
Bacteria convert easily decomposable organic matter additions into humus. Fungi convert more recalcitrant organic matter, such as lignin,
into humus. Protozoa feed on bacteria and release nutrients to the soil solution as a by-product of this activity.
Nematodes dan micro-arthropods memangsa bakteri dan fungi, serta melepaskan sejumlah hara ke dalam larutan tanah.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
“The numbers, biomass, activity and community structure of the organisms which comprise the soil foodweb can be used as indicators of ecosystem health because these organisms perform critical processes and functions” (Ingham, 2000).
Dalam ekosistem yang sehat, biasanya siklus hara dan produktivitasnya meningkat, kehilangan hara minimum.
Hal ini dapat dicapai dengan jalan meningkatkan kompleksitas “foodweb” tanah .
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
Kalau BOT ditambahkan, organisme tanah memakan BO itu dan men-dekomposisi senyawa organik kompleks menjadi
senyawa mineral (anorganik).
The living soil is a central part of soil fertility, because the activity of soil organisms renders available the elements in
plant residues and organic debris entering the soil.
Sebagian dari bahan organik ini tetap berada dalam tanah (humus) dan membantu stabilitas tanah (Fleissbach et al.,
2000).
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
A healthy soil foodweb has adequate populations of soil decomposers (bacteria and fungi) to retain nutrients within the soil.
In agricultural systems it is in our best interest :1. to promote a healthy soil foodweb so that we can make the most
efficient use of plant nutrients. 2. When we minimize nutrient losses from the soil, we are saving dollars
spent on purchased fertilizers. 3. We also minimize off-site damage from lost nutrients, which can end up
in groundwater. 4. That, in turn, can produce health-related costs including nitrate toxicity,
which particularly affects young children and livestock. Nutrients that do not leach to the groundwater can be lost in surface waters.
Preventing nutrient loss through a healthy soil foodweb enhances productivity and avoids both fertilizer costs and water quality
deterioration.Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia
Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
Mengukur Kesehatan Foodweb Tanah
Ada banyak cara mengkaji organisme tanah dan menghubungkan hasil-hasilnya dengan kesehatan ekosistem. Biomasa dan aktivitas fungi dan
bakteri dapat diukur. The ratio of fungal to bacterial biomass is a useful indicator of foodweb
structure. Forest soils are typically dominated by fungi and have a fungal:bacterial biomass ratio (F:B) of greater than one. Fungi effectively decompose recalcitrant organic matter producing secondary metabolites
which make the soil more acidic. Sebagian terbesar N dalam fungi-tanah berbentuk ammonium, yang sangat disenangi oleh pertumbuhan belukar dan pohon-pohon.. Prairie grasslands tend to be dominated by bacteria (F:B<1). These soils are characterized by
alkaline conditions and nitrate/nitrite as the dominant form of soil N. These conditions are beneficial for grasses and row crops.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
Mengukur Kesehatan Foodweb Tanah
Infertile agricultural soils in Nova Scotia are probably characterized by an excess of fungi relative to bacteria (F:B>1). Fungi tend to dominate
in acidic soil conditions, typical of the Podzolic soils of this region.Soil acidity also becomes a problem when synthetic nitrogen fertilizers
are used on crop land. The ammonium contained in commercial fertilizers is converted to nitrate (nitrification) in the soil and hydrogen
ions are released, contributing to acidification. This acidification results in the constant need to lime agricultural soils.
Kondisi masam menurunkan produktivitas tanah-tanah pertanian karena problematik seperti toksisitas hara dan reduksi ketersediaan
hara tertentu, terutama fosfat.
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KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
Mengukur Kesehatan Foodweb Tanah
In the soil quality index developed by Glover et al. (2000), several measures of soil foodweb health (biological activity) are used.
Dalam lapisan topsoil 15 cm, mereka menilai (urut kepentingannya)1. C-organik tanah (t/ha);2. Banyaknya cacing tanah per m2;3. C biomasa mikroba (kg/ha); 4. N biomasa mikroba (kg/ha).
Glover, J., J. Reganold, & P. Andrews. (2000). “Systematic method for rating soil quality of conventional, organic, and integrated apple orchards in Washington State.” Agriculture Ecosystems and Environment
80, 29-45.Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia
Cooper. September, 2002. gpi aTLANTIC
Mengukur Kesehatan Foodweb Tanah
Soils amended with composted manure or grass/legume residues have shown higher levels of microbial biomass carbon than conventionally
managed soils (Glover et al., 2000). In Switzerland, researchers assessed microbial biomass carbon in treatments using composted manure and no synthetic fertilizer or pesticides. These treatments had 20-40% higher microbial biomass compared to treatments fertilized with manure
plus synthetic fertilizer and pesticides, and 60-85% higher microbial biomass compared to treatments with synthetic fertilizer and pesticides (Fleissbach et al.,
2000). Earthworm density and biomass followed a similar trend, where treatments
receiving composted manure and no synthetic pesticides had 30 to 80% higher earthworm density and biomass compared to treatments using
synthetic fertilizer and pesticides (Fleissbach et al., 2000).
1. Fliessbach, A., P.Mäder, D.Dubois, & L.Gunst. (2000). Results from a 21 year old field trial. FiBL Dossier 1:1-15.2. Glover, J., J. Reganold, & P. Andrews. (2000). “Systematic method for rating soil quality of conventional, organic, and
integrated apple orchards in Washington State.” Agriculture Ecosystems and Environment 80, 29-45.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
Mengukur Kesehatan Foodweb Tanah
Very little research has been done on soil foodweb analysis in Nova Scotia. Research into microbial activity (a component of soil foodweb analysis) is also scarce. In the early nineties, Cooper and Warman (1997) conducted an experiment in which they added either fresh or composted manure, or synthetic (NPK) fertilizer, to hayfields near Truro, every year for three years. Microbial activity was measured using the
dehydrogenase enzyme activity assay.Of the two sites they used, the one with the lower soil organic carbon levels showed a biological response to organic matter additions; plots that had been amended with
either manure or compost always had higher dehydrogenase enzyme activity (microbial activity) than synthetically fertilized plots.
Mikroba tanah di-stimulir oleh penambahan kompos atau pupuk kandang. Kandungan hara-tersedia dalam tanah dan pH tanah juga meningkat setelah
penambahan kompos atau pupuk kandang. Dosis aplikasi pupuk kandang digunakan sebagai cara tidak langsung untuk menduga
kesehatan foodweb tanah.
1. Cooper, J.M. & Warman, P.R. (1997). “Effects of three fertility amendments on soil dehydrogenase activity, organic C and pH.” Canadian J. Soil Sci. 77,281-283.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
Table 21: Metode Pendugaan Foodweb Tanah yang Sehat
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
Kuantitas Mikroba TanahMikroba tanah menghasilkan beragam jasa-jasa ekosistem yg penting
bagi masyarakat, di antaranya adalah:1. SIKLUS HARA – conversion of nutrients from organic residues into plant available
forms ready for plant uptake.2. DEGRADASI PESTISIDA – conversion of active ingredients in pesticides into less
harmful products, and their eventual conversion into CO2 and water3. KONTROL PENCEMARAN – conversion of labile plant nutrients such as nitrate
and phosphate, into more stable organic forms4. SIMPANAN KARBON – formation of stable humus from organic residues.5. FIKSASI NITROGEN – fixation of 140 to 170 million tonnes of N each year in
agricultural and natural systems by free-living and symbiotic microorganisms6. KONTROL PATOGEN – neutralization of disease organisms that could attack
crops; control of disease organisms found in animal wastes applied to agricultural land.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
Table 22: Nilai-nilai Foodweb yang Sehat
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS: Soil Foodweb Health
Nilai foodweb tanah yang sehat sulit dikuantifikasikan. Mikroba tanah memainkan beragam fungsi dan jasa ekosistem, seperti siklus
hara, fixation dan retention, purifikasi limbah, dan detoksifikasi pesticides dan bahan kimia.
The rotation effect is one benefit attributed to a healthy soil foodweb.
We can estimate that crop yields on land with a healthy soil microbial population are 10% higher than yields on land with poor soil health because of the competitive interactions between a diversity of soil
microorganisms which prevent the proliferation of deleterious rhizobacteria.
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITASTable 23: Kualitas Tanah dan Indikator Produktivitas
Sumber: GPI AGRICULTURE ACCOUNTS, PART TWO: RESOURCE CAPACITY AND USE: SOIL QUALITY AND PRODUCTIVITY. Jennifer Scott and Julia Cooper. September, 2002. gpi aTLANTIC
KUALITAS TANAH DAN PRODUKTIVITAS
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