910 likes | 1.49k Views
EVALUASI KEMAMPUAN LAHAN. Bahan kajian MK STELA smno fpub Mei 2013. PENDAHULUAN. Lahan : bagian bentang alam ( lansekap ) yang mencakup pengertian lingkungan fisik : termasuk iklim , topografi , hidrologi & keadaan vegetasi alam
E N D
EVALUASI KEMAMPUAN LAHAN Bahankajian MK STELA smnofpub Mei 2013
PENDAHULUAN • Lahan: bagianbentangalam (lansekap) yang mencakuppengertianlingkunganfisik: termasukiklim, topografi, hidrologi & keadaanvegetasialam • Pemanfaatanlahansudahsemakinintensif, sehinggasebagianbesartelahmelampauidayadukungnya. • Adaupayauntukmengetahuikelaskemampuanlahandankelaskesesuaianlahannya.
KEMAMPUAN LAHAN Soil quality in relation to soil properties, soil processes, and environmental quality Sumber: http://archive.unu.edu/unupress/unupbooks/uu27se/uu27se03.htm
SUMBERDAYA LAHAN LahandanSumberdayaLahanmenunjukkan area tertentudipermukaanbumimeliputisemuaattributbiosfirdiatasdandibawahpermukaan, seperti: Iklimdidekatpermukaanbumi, Tanah danlansdkap, Hidrologipermukaan (including shallow lakes, rivers, marshes and swamps), The near-surface sedimentary layers and associated groundwater and geohydrological reserve, The plant and animal populations, The human settlement pattern and Physical results of past and present human activity (terracing, water storage or drainage structures, roads, buildings, etc.) (FAO/UNEP, 1997). Sumber: http://www.fao.org/docrep/004/x3810e/x3810e04.htm
FUNGSI LAHAN a store of wealth for individuals, groups, or a community production of food, fibre, fuel or other biotic materials for human use provision of biological habitats for plants, animals and micro-organisms co-determinant in the global energy balance and the global hydrological cycle, which provides both a source and a sink for greenhouse gases regulation of the storage and flow of surface water and groundwater storehouse of minerals and raw materials for human use a buffer, filter or modifier for chemical pollutants provision of physical space for settlements, industry and recreation storage and protection of evidence from the historical or pre-historical record (fossils, evidence of past climates, archaeological remains, etc.) enabling or hampering movement of animals, plants and people between one area and another. Sumber: http://www.fao.org/docrep/004/x3810e/x3810e04.htm
KETERSEDIAAN LAHAN Land is becoming more and more scarce as a resource, and this is particularly true of land available for primary production of biomass or for conservation related purposes. Competition for land among different uses is becoming acute and conflicts related to this competition more frequent and more complex. This competition is often most apparent on the peri-urban fringe, where the continuing pressures of urban expansion compete with agricultural enterprises, and with recreational demands. Such situations frequently lead to rapid increases in the economic value of land, and land tenure becomes an important political issue. Many factors associated with global change directly or indirectly influence how land is used. These include biophysical influences, such as changes in climate or natural or human-induced disasters, as well as socio-economic aspects such as trade liberalization, the globalization of markets, decentralization of decision making, privatization, and the widening gap between the "haves" and the "have-nots". Sumber: http://www.fao.org/docrep/004/x3810e/x3810e04.htm
PROBLEMATIK LAHAN The symptoms of the problem of pressure on land resources are manifested both in terms of impacts on people, and in terms of deterioration in the condition of land or impacts on other natural resources . The deterioration in land condition may be reflected by an impaired ability to carry out any functions of the land listed above, some of which, such as reduced capacity to produce biomass, also, in turn, affect population support or quality of life. Sumber: http://www.fao.org/docrep/004/x3810e/x3810e04.htm
SYMPTOMS OF THE PROBLEM OF PRESSURE ON LAND AND RESOURCES Sumber: http://www.fao.org/docrep/004/x3810e/x3810e04.htm
CAUSE-PROBLEMS - SYMPTOM RELATIONSHIP Sumber: http://www.fao.org/docrep/004/x3810e/x3810e04.htm
THE SPIRAL: LAND RESOURCES AND PEOPLE'S ACTIVITIES Sumber: http://www.fao.org/docrep/004/x3810e/x3810e04.htm
KEMAMPUAN LAHAN Land Capability Land capability is the ability of a piece of land to sustainably support a specific land use. If land is used beyond its capability, degradation is the consequence. Land capability is based on the understanding that every component of land has its own particular capacity to provide ecosystem services. It also propounds that a significant proportion of this capacity is required to maintain soil and land health (primary services) and that the remaining capacity is then potentially available for a range of human enterprises (secondary services). Land capability assessment therefore enables the reconciliation of production and protection. Sumber: http://vro.dpi.vic.gov.au/dpi/vro/vrosite.nsf/pages/soilhealth_land_cap_model
KEMAMPUAN LAHAN Land Capability Ecologically sustainable uses must be those which do not compromise the primary ecosystem services. The corollary is that the soil and land can then be regarded as healthy. If, conversely, land is used such that the primary ecosystem services are compromised then, by definition, land degradation has occurred. The level of ecosystem services available will depend on the land component features, and its topographic and climatic environment. It is not possible to provide levels as a simple representation, although they will closely relate to our integrated understanding of land and soil quality. Seasonal variation compounds the issue. Climatic variation adds a new dimension entirely. Sumber: http://vro.dpi.vic.gov.au/dpi/vro/vrosite.nsf/pages/soilhealth_land_cap_model
KEMAMPUAN LAHAN Land Capability The sustainable harvest of particular goods and services will thus be directly related to the availability of surplus ecosystem service capacity (i.e. that over and above that require for basic ecosystem activity). Health is lost if harvest (and its associated management) removes goods and services required for basic ecosystem activity Land capability does not include social or economic components. It focuses entirely on requirements for sustainability of the ecosystem. After the assessment of land capability, there is the requirement to overlay this then with the social and the economic constraints. Then, thus, we have land suitability assessment. Sumber: http://vro.dpi.vic.gov.au/dpi/vro/vrosite.nsf/pages/soilhealth_land_cap_model
KEMAMPUAN LAHAN Sumber: http://vro.dpi.vic.gov.au/dpi/vro/vrosite.nsf/pages/soilhealth_land_cap_model
KEMAMPUAN LAHAN Land capability classification is - according to the USDA terminology - "a system of grouping soils primarily on the basis of their capability to produce common cultivated crops and pasture plants without deteriorating over a long period. Land capability classification is subdivided into capability class and capability subclass nationally. Capability class The broadest category in the system. Class codes I to VIII indicate progressively greater limitations and narrower choices for agriculture. The numbers are used to represent both irrigated and nonirrigated land capability. Sumber: http://www.conservapedia.com/Land_capability_classification
DayaDukungLahan • DDL menunjukkankemampuansuatulahanuntukpenggunaantertentu • Misalnya: • Kebutuhanpangan, • Kebutuhanpakanternak, • Ketersediaan air, dll • Contoh: • Lahansawahdi Kota Malang hanyamampumenyediakanpangan (beras) bagi 200000 jiwa, sehinggasisanyaharusmendatangkandariluas Kota Malang
DayaDukungLahan • Untukmengetahuidayadukunglahantersebutseringdigunakananalisiskemampuanpenggunaanlahan (KPL). • KPL inisebenarnyadikembangkanuntuktujuankonservasitanah, tetapirekomendasipenggunaannyadapatmenyiratkanberapaluaslahan yang masihlayakuntuktujuantertentu.
INVENTARISASI Bentuk lahan Batuan Tanah Lereng Erosi Upaya konservasi tanah Penutupan lahan/ Penggunaan lahan Tabulasi dan plot inventarisasi faktor tunggal dan majemuk SISTEM SURVEI SUMBERDAYA LAHAN Informasi Iklim dan Hidrologi PENILAIAN KEMAMPUAN PENGGUNAAN LAHAN (KPL) Kelas Sub Kelas Satuan Plot dan Tabulasi KPL DATA SOSIAL EKONOMI Diagram kerangka survei sumberdaya lahan PENGGUNAAN LAHAN YANG DIREKOMENDASIKAN UNTUK PERENCANAAN PENGELOLAAN DAS TERPADU
DEFINISI “KEMAMPUAN LAHAN” adalah kemampuansuatulahanuntukdigunakansebagaiusahapertanian yang paling intensftermasukpenentuantindakanpengelolaannya, tanpamenyebabkanlahantersebutmenjadirusak. Pembatas Ber-beda2 Kemampuan Berbeda Sifat Lahan Berbeda
KPL = KEMAMPUAN PENGGUNAAN LAHAN • KPL = Sistemklasifikasilahan yang dikembangkanterutamauntuktujuankonservasitanah • Mempertimbangkankelestarianlahandalammenopangusahapertaniansecaraluas : budidayatanaman, padangrumput, agroforestry.
KLASIFIKASI KEMAMPUAN LAHAN Land capability classification shows, in a general way, the suitability of soils for most kinds of field crops. Crops that require special management are excluded. The soils are grouped according to their limitations for field crops, the risk of damage if they are used for crops, and the way they respond to management. The criteria used in grouping the soils do not include major and generally expensive landforming that would change slope, depth, or other characteristics of the soils, nor do they include possible but unlikely major reclamation projects. Capability classification is not a substitute for interpretations designed to show suitability and limitations of groups of soils for rangeland, for forestland, or for engineering purposes. Sumber: http://www.udel.edu/FREC/spatlab/oldpix/nrcssoilde/Descriptions/landcap.htm
Hirarki KlasifikasiKemampuanLahan(Stallings, 1957) Ada 2 DIVISI (1) Dapat diusahakan dan (2) Tidak dapat diusahakan [untuk PERTANIAN] Ada 8 KELAS , yang pembagiannya didasarkan pada Faktor Pembatas Permanen Pembagian SUB-KELAS didasarkan pada Macam Faktor Pembatas Pembagian SATUAN PENGELOLAAN didasarkan pada Perlakuan Pengawetan dan Pemupukan
STRUKTUR Jenis pembatas utama SUB KELAS E = erosi W = kebasahan S = tanah c = iklim G = gradien Kemiripan kebutuhan dan konservasi tanah SATUAN
KelasKemampuanLahan • KelasKemampuanLahanmendeskripsikan total derajadpembatasdarinolataudapatdiabaikanpadakelas I hinggatingkatekstrempadakelas VIII. KelasiniditulisdenganmenggunakanangkaRomawi. • Contoh : Kelas VI, Kelas V, dst.
Sub Kelas: • menunjukkan jenis pembatas utama yang meliputi: • erosi = e, • kebasahan = w; • karakteristik tanah (s) dan • gradien (g). • Contoh: Subkelas = VIe
Satuan • Pengelompokan beberapa satuanpetainventarisasi yang mempunyai kemiripan yang sama • Mempunyai hasil potensial yang hampir sama, • Memerlukan upayakonservasi tanah yang sama • Contoh : VIe1, VIe2, dsb
Asumsi-1 • KPL adalahsuatupenilaianbersifatinterpretasiberdasarkansifatfisiklahan yang permanen • Bilapetanitelahataubisamengatasisendirimasalahtersebut, lahandinilaidengantingkatpembatas yang masihtersisasetelahmengalamiperbaikan • Tingkat pengelolaanlahandiatas rata-rata • Telahditerapkanupayakonservasitanah yang memadaiuntukpemeliharaan
Asumsi-2 • KPL bukansuatupenilaianproduktivitasterhadaptanamantertentu, meskinisbahmasukandankeluaranbisamembantumenetapkan KPL • Misal : padatingkatpengelolaan yang sama, tingkatproduksipada KPL III >KPL IV • KPL bisaberubahkarenareklamasi : drainase, irigasi, pengendalianbanjir, dll. • Tidakdipengaruhioleh faktor-2 seperti: lokasi, jarakdaripasar, fasilitasprosesing, pemilikanlahanataupenampilanindividupetani.
PEMBATAS FISIK • KarakteristikLahan yang mempunyaiakibatmerugikanterhadapkeragaan (performance) lahan • Ditunjukkandalam Sub KelasKemampuanPenggunaanLahan • Pembatasfisikdapatberupa: • Pembataspermanen • Pembatasberubah (dapatdihilangkanataudiperbaikiimelalui praktek-2 usahatani)
PembatasPermanen • Sifat-2 jenisbatuan • Sifattanah : kedalamanperakaran, adanyalapisanpenghambatdalamtanah, tekstur, kapasitasmenahan air, jenis mineral liat, dll • Iklim yang kurangcocok • Bahayaalam (gunungapi, banjir, dsb) • Kebasahantanahberlebihsetelahdrainase • Erosidangerakanmassa • Kemiringanlereng
KEDALAMAN PERAKARAN Average root depth for various crops. Sumber: http://www.ext.nodak.edu/extnews/snouts/spout228.htm
Depths to which the roots of mature crops will deplete the available water supply when grown in a deep permeable, well-drained soil under average conditions. Sumber:"Sprinkler Irrigation," Section 15, Natural Resources Conservation Service National Engineering Handbook
KEDALAMAN EFEKTIF TANAH Root test: dig into soil near an established plant. Look for fine hairy roots (not just coarse roots which indicate poor drainage) going deep with no sharp turns (hard pan) Sumber: http://www.southerngreenliving.com/2011/08/field-soil-tests.html
KAPASITAS MENAHAN AIR Water holding capacity designates the ability of a soil to hold water. It is useful information for irrigation scheduling, crop selection, groundwater contamination considerations, estimating runoff and determining when plants will become stressed. Water holding capacity varies by soil texture. Sumber: http://passel.unl.edu/pages/informationmodule.php?idinformationmodule=1130447039&topicorder=10&maxto=10
KAPASITAS MENAHAN AIR Calculation of water holding capacity for a soil profile Sumber: http://passel.unl.edu/pages/informationmodule.php?idinformationmodule=1130447039&topicorder=10&maxto=10
KAPASITAS MENAHAN AIR Soil Texture and Water Holding Capacity Sumber: http://enoviti-hanumangirl.blogspot.com/2012/06/soil-texture-and-water-holding-capacity.html
FaktorPembatas Non-permanen (Berubah) • Kekuranganhara • Kebasahantanahataukerentananterhadapbanjir • Keberadaanbatupadapermukaanlahanataudizonaperakarantanaman • Erosi : lapis, alurataujurang • Catatan : tergantungdaritingkatannya • Katakunci: pantas, layakdanekonomisperludipertimbangkansewaktumemutuskankepraktisandalammenghilangkanataumemodifikasipembatas.
KETERSEDIAAN HARA pH and Nutrient Availability chart Sumber: http://www.growing-life.com/shop/pH_and_Nutrient_Availability_chart.html
KETERSEDIAAN HARA. Phosphorus and potassium are immobile nutrients in the soil. P and K requirements for canola change, depending on soil test index levels. A phosphorus soil test index of 65 and above is considered 100 percent sufficient for crop growth, and anything less should be adjusted based on the recommendation in Table 1. Similarly, a K soil test index level of 250 or more is considered 100 percent sufficient, and anything less should be adjusted based on the recommendation in Table 2. Phosphorus and potassium needs should be corrected before planting by broadcast application and incorporation into the soil. Sumber: http://www.noble.org/ag/soils/winter-canola/
KETERSEDIAAN HARA Sumber: http://ag.arizona.edu/crop/cotton/soilmgt/soil_fertility_testing.html
KETERSEDIAAN NITROGEN Sumber: http://www.sbreb.org/research/soil/soil74/74p91.htm
KELAS KPL • Delapankelas: I - VIII • Disusundalamurutansesuaidengan • peningkatanfaktorpembatasatauancamanuntukdigunakan, atau • penurunandalamanekapenggunaanlahan
KELAS KEMAMPUAN LAHAN Class 1 soils have slight limitations that restrict their use. Class 2 soils have moderate limitations that restrict the choice of plants or that require moderate conservation practices. Class 3 soils have severe limitations that restrict the choice of plants or that require special conservation practices, or both. Class 4 soils have very severe limitations that restrict the choice of plants or that require very careful management, or both. Class 5 soils are subject to little or no erosion but have other limitations, impractical to remove, that restrict their use mainly to pasture, rangeland, forestland, or wildlife habitat. Class 6 soils have severe limitations that make them generally unsuitable for cultivation and that restrict their use mainly to pasture, rangeland, forestland, or wildlife habitat. Class 7 soils have very severe limitations that make them unsuitable for cultivation and that restrict their use mainly to grazing, forestland, or wildlife habitat. Class 8 soils and miscellaneous areas have limitations that preclude commercial plant production and that restrict their use to recreational purposes, wildlife habitat, watershed, or esthetic purposes.
Kelas I-IV • Ditetapkanataskesesuaiannyauntukbudidayatanamantanpateras. • Sesuaiuntukbudidayatanamanpertanianpadateras, danmempunyaipembatasfisik yang meningkatuntuktanamanpertaniantanpateras • Kelas I: Tidakmemilikipembatas sawahirigasi • Kelas II: Pembatasfisikringan, sedikitupayakonservasi sawahirigasiatau yang lainnya • Kelas III: Pembatasfisiksedang, perluupayakonservasi sesuaiuntuksegalabentukusahatani • Kelas IV: Pembatasfisikberat, perluupayakonservasitanahintensif kurangcocokuntukusahatani non teras • Jugasesuaiuntukpadangrumput, agroforestryatauhutan
SAWAH IRIGASI SawahIrigasiteknisdiKab. Tulungagung Sumber:
SAWAH IRIGASI: diKab.. Ngawi Sumber:
Kelas V • Tidaksesuaiuntukbudidayatanamanpertaniantanpateras • Sesuaiuntukbudidayatanamanpertaniandenganteras, agroforestry, padangrumputatauhutan
TEKNOLOGI TERRASERING Bench terraces are a soil and water conservation measure used on sloping land with relatively deep soils to retain water and control erosion. They are normally constructed by cutting and filling to produce a series of level steps or benches. This allows water to infiltrate slowly into the soil. Bench terraces are reinforced by retaining banks of soil or stone on the forward edges. This practice is typical for rice-based cropping systems. Sumber: http://www.nzdl.org/gsdlmod?
TEKNOLOGI TERRASERING The velocity of water increases as slope length increases. Decreasing slope length by planting rows perpendicular to the slope or by adding terraces can decrease the velocity of water and, as a result, decrease its erosive potential. Sumber: http://croptechnology.unl.edu/pages/printinformationmodule.php?idinformationmodule=1088801071
TEKNOLOGI AGROFORESTRY Agroforestryis an agricultural approach of using the benefits from combining trees and crops and/or livestock. Therefore, knowledge on selection of species combination and good management of trees and crops are needed to maximize the production and positive effects of trees and to minimize negative competitive effects on crops. Sumber: http://www.worldagroforestry.org/sea/Wanulcas