Bahan Kuliah dan Tugas Ujian MK. Sistem Pertanian Lahan Kering

Bahan kuliah ini berisikan pemahaman tentang makna kata dry, dry land, farming dan dry land farming, peternakan lahan kering dan kondisi umum NTT. Silakan anda mempelajarinya baik-baik.
(Anda dapat meng-click kata-kata yang dicetak berwarna dan bergaris bawah di sepanjang bahan ini untuk mengetahui artikel tentang kata tersebut).

Dryland farming is an agricultural technique for cultivating land which receives little rainfall.

Apa maksudnya little rainfall? silakan click pada kata rainfall.

Dryland farming is used in the Great Plains, the Palouse plateau of Eastern Washington regions of North America, the Middle East and in other grain growing regions such as the steppes of Eurasia and Argentina. Dryland farming was introduced to the southern Russian Empire by Russian Mennonites under the influence of Johann Cornies, making the region the breadbasket of Russia.^[1] Winter wheat is the typical crop although skilled dryland farmers sometimes grow corn, beans or even watermelons. Successful dryland farming is possible with as little as 15 inches (380 mm) of precipitation a year, but much more successful with 20 inches (510 mm) or more. It is also known that Native American tribes in the arid SouthWest subsisted for hundreds of years on dryland farming in areas with less than 10 inches (250 mm) of rain.

In marginal regions, a farmer should be financially able to survive occasional crop failures, perhaps of several years running. A soil which absorbs and holds moisture is helpful as is the practice of leaving stubble standing in the field to catch blowing snow.

Arti kata dry dalam konteks arid dan wilting: in general terms, the climate of a locale or region is said to be arid when it is characterized by a severe lack of available water, to the extent of hindering or even preventing the growth and development of plant and animal life. As a result, environments subject to arid climates tend to lack vegetation and are called xeric or desertic.

The expression 'available water' refers to water in the soil in excess to the wilting point. The air over a hot desert may actually contain substantial amounts of water vapor but that water may not be generally accessible to plants, except for very specialized organisms (such as some species of lichen). 'Lack of water' refers to use by plants. The water that is actually present in the environment may be sufficient for some species or usages (such as climax vegetation), and grossly insufficient for others. Aridity, the characteristic nature of arid climates, may thus depend on the use of the land. Regards to the presence of life, what is more important than the degree of rainfall is the fraction of precipitation that is not quickly lost through evaporation or runoff. Attempts to quantitatively describe the degree of aridity of a place has often led to the development of aridity indexes. There is no universal agreement on the precise boundaries between classes such as 'hyper-arid', 'arid', 'semi-arid', etc.

Selanjutnya, apa makna kata farming? Anda dapat memeriksanya melalui pemahaman tentang ARGICULTURE. Silakan periksa bahan di bawah ini

Agriculture refers to the production of goods through the growing of plants, animals and other life forms. The study of agriculture is known as agricultural science.

Agriculture encompasses many subjects, including aquaculture, agronomy, animal husbandry, and horticulture. Each of these subjects can be further partitioned: for example, agronomy includes both sustainable agriculture and intensive farming, and animal husbandry includes ranching, herding, and intensive pig farming. Agricultural products include food (vegetables, fruits, and cereals), fibers (cotton, wool, hemp, silk and flax), fuels (methane from biomass, ethanol, biodiesel), cut flowers, ornamental and nursery plants, tropical fish and birds for the pet trade, both legal and illegal drugs (biopharmaceuticals, tobacco, marijuana, opium, cocaine), and other useful materials such as resins. Recently crops have been designed to produce plastic^[1] as well as pharmaceuticals.^[2]

The history of agriculture is a central element of human history, as agricultural progress has been a crucial factor in worldwide socio-economic change. Wealth-building and militaristic specializations rarely seen in hunter-gatherer cultures are commonplace in agricultural and agro-industrial societies—when farmers became capable of producing food beyond the needs of their own families, others in the tribe/village/City-state/nation/empire were freed to devote themselves to projects other than food acquisition. Jared Diamond, among others, has argued that the development of civilization required agriculture.

As of 2006, an estimated 36 percent of the world's workers are employed in agriculture (down from 42% in 1996). However, the relative significance of farming has dropped steadily since the beginning of industrialization, and in 2006 – for the first time in history – the services sector overtook agriculture as the economic sector employing the most people worldwide.^[3] Despite the fact that agriculture employs over one-third of the world's population, agricultural production accounts for less than five percent of the gross world product (an aggregate of all gross domestic products).^[4]

Crop alteration

Domestication of plants has, over the centuries increased yield, improved disease resistance and drought tolerance, eased harvest and improved the taste and nutritional value of crop plants. Careful selection and breeding have had enormous effects on the characteristics of crop plants. Plant breeders use greenhouses (known as glasshouses or hothouses in some areas) and other techniques to get as many as three generations of plants per year towards the continued effort of improvement. Plant selection and breeding in the 1920s and 1930s improved pasture (grasses and clover) in New Zealand. Extensive X-ray an ultraviolet induced mutagenesis efforts (i.e. primitive genetic engineering) during the 1950s produced the modern commercial varieties of grains such as wheat, corn and barley.^[22][23]

For example, average yields of corn (maize) in the USA have increased from around 2.5 tons per hectare (t/ha) (40 bushels per acre) in 1900 to about 9.4 t/ha (150 bushels per acre) in 2001. Similarly, worldwide average wheat yields have increased from less than 1 t/ha in 1900 to more than 2.5 t/ha in 1990. South American average wheat yields are around 2 t/ha, African under 1 t/ha, Egypt and Arabia up to 3.5 to 4 t/ha with irrigation. In contrast, the average wheat yield in countries such as France is over 8 t/ha. Variation in yields are due mainly to variation in climate, genetics, and the level of intensive farming techniques (use of fertilizers, chemical pest control, growth control to avoid lodging).^[24][25][26]

After mechanical tomato-harvesters were developed in the early 1960s, agricultural scientists bred tomatoes that were more resistant to mechanical handling. These varieties have been criticized as being harder and having poor texture^{[citation needed]}. More recently, genetic engineering has begun to be employed in large parts of the world to speed up the selection and breeding process. One widely used modification is a herbicide resistance gene that allows plants to tolerate exposure to glyphosate, a non-systemic (i.e kills all plants) chemical used to control weeds in a crop such as oilseed rape. Normally, expensive systemic herbicides would have to be applied to kill the weeds without harming the crop. Relatively cheap and safe glyphosate may be applied to the modified crops, efficiently killing weeds without harming the resistant crop. Another modification causes the plant to produce a toxin to reduce damage from insects (c.f. Starlink). This, in contrast, requires fewer insecticides to be applied to the crop.

Aquaculture, the farming of fish, shrimp, and algae, is closely associated with agriculture.

Apiculture, the culture of bees, traditionally for honey—increasingly for crop pollination.

Livestock

The farming practices of livestock vary dramatically world-wide and between different types of animals. Livestock are generally kept in an enclosure, are fed by human-provided food and are intentionally bred, but some livestock are not enclosed, or are fed by access to natural foods, or are allowed to breed freely, or all three. Approximately 68% of all agricultural land is used in the production of livestock as permanent pastures.<sup>[27] (kalau ingin melihat pengertian pasture maka keluar dan pelajari bahan kuliah padang rumputdalam blog ini juga).

Mau tahu lebih lanjut tentang peternakan maka ikuti artikel di bawah ini</sup>

Animal husbandry, also called animal science, stockbreeding or simple husbandry, is the agricultural practice of breeding and raising livestock.

The science of animal husbandry is taught in many universities and colleges around the world. Students of animal science may pursue degrees in veterinary medicine following graduation, or go on to pursue master's degrees or doctorates in disciplines such as nutrition, genetics and breeding, or reproductive physiology. Graduates of these programs may be found working in the veterinary and human pharmaceutical industries, the livestock and pet supply and feed industries, or in academia.

Historically, certain sub-professions within the field of animal husbandry are specifically named according to the animals that are cared for.

Different types of animal husbandry

A swineherd is a person who cares for hogs and pigs (older English term: swine). A shepherd is a person who cares for sheep. A goatherd cares for goats. A cowherd cares for cattle. In previous years, it was common to have herds which were made up of sheep and goats. In his case, the person tending them was called a shepherd. Camels are also cared for in herds. In Tibet yaks are herded. In Latin America, llamas and alpacas are herded.

In more modern times, the cowboys or vaqueros of North and South America ride horses and participate in cattle drives to watch over cows and bulls raised primarily for food. In Australia many herds are managed by farmers on motorbikes and in helicopters. Today, herd managers often oversee thousands of animals and many staff. Farms and ranches may employ breeders, herd health specialists, feeders, and milkers to help care for the animals. Techniques such as artificial insemination and embryo transfer are frequently used, not only as methods to guarantee that females are bred, but to help improve herd genetics. This may be done by transplanting embryos from stud-quality females, into flock-quality surrogate mothers - freeing up the stud-quality mother to be reimpregnated. This practice vastly increases the number of offspring which may be produced by a small selection of stud-quality parent animals. This in turn improves the ability of the animals to convert feed to meat, milk, or fiber more efficiently and improve the quality of the final product.

here are contrasting views on the ethical aspects of breeding animals in captivity, with one debate being in relation to the merits of allowing animals to live in natural conditions which are reasonably close to those of their wild ancestors, compared to the view that considers natural pressures and stresses upon wild animals from disease, predation, and the like as vindication for captive breeding.

Aspek Etik dari Peternakan

Some techniques of animal husbandry such as factory farming, tail docking, the Geier Hitch, and castration, have been condemned by animal welfare activists and groups such as Compassion In World Farming. Some of these practices also are criticized by farmers who use more traditional or organic practices. Many scientists agree that organic practices are healthier for the animals and the environment. Genetic engineering is also controversial though it does not necessarily (but usually does) involve suffering. Animal rights activists are often opposed to all forms of animal husbandry.

Some domesticated species of animals, such as the vechur cow, are rare breeds and are endangered. They are the subject of conservation efforts.

Bagaimana Praktek Sistem Peternakan Lahan Kering

Potensi lahan kering diabaikan

Alih fungsi lahan menjadi tempat pemukiman, mengancam keberadaan lahan sawah produktif. Walaupun masih ada lahan sawah, keberadaannya sudah tak layak untuk diusahakan sebagai sawah berpengairan baik. Sayangnya, kini penggarapan potensi lahan kering masih diabaikan, padahal luas lahan ini jauh di atas sawah.

''Jadi, bisa dikatakan sawah bukan lagi satu-satunya tulang punggung pertanian dan penghasil utama produksi pangan. Karena itu pengembangan pertanian di lahan kering menjadi suatu yang penting,'' kata guru besar Fakultas Pertanian Unud Prof. Ir. IGA Mas Sri Agung , M.Rur.Sc., Ph.D. saat seminar pengembangan pertanian lahan kering menuju petani sejahtera yang digelar PS Magister Pertanian Lahan Kering Unud, Sabtu (22/7). Saat ini, 20 persen total luas Indonesia adalah lahan kering. Di Bali, 85,26 persen atau 480.559 hektar dari luas lahan pertanian di Bali adalah lahan kering. Dari luas sebanyak itu, 42,10 persen (202.335 hektar) berada di Bali Utara.

Dikatakannya, lahan kering mempunyai potensi yang lebih besar dibandingkan lahan sawah. Di samping sebagai penghasil pangan, lahan kering juga menghasilkan produk pertanian lainnya dalam arti luas seperti perkebunan, peternakan dan perhutanan. Namun, selama ini potensi itu terabaikan.

Guru besar ilmu tanah Fakultas Pertanian Unud Prof. I Nyoman Merit mengatakan lahan kering sebagai aset nasional mempunyai potensi yang sangat besar untuk dikembangkan sepanjang faktor pembatasnya dapat dikendalikan. Pencegahan erosi dan pengelolaan lahan secara bijak merupakan keharusan jika lahan kering hendak dibudidayakan.

Guru besar dalam bidang agronomi Fak. Pertanian Unud Prof. Dewa Ketut Suanda mengatakan usaha intensifikasi dalam pertanian penting dilakukan agar produksi dan pendapatan mencukupi kebutuhan petani. Petani mesti juga pintar memilih komoditas yang akan dipadukan dalam usaha tani terpadu yaitu yang kompatibel, mudah diproduksi dan produknya mampu dijual dengan harga tinggi.

(Sumber: Bali Post, 01/08/2006

PENGKAJIAN SISTEM USAHA TANI (SUT) KONSERVASI DAN INTEGRASI
TANAMAN TERNAK DI LAHAN KERING DATARAN RENDAH
AGUS NURAWAN, A. HANAFIAH dan SAEFUL BACHREIN

Balai Pengkajian Teknologi Pertanian Jawa Barat, Lembang

ABSTRAK

Usaha tani di lahan kering dataran rendah memiliki karakteristik yang berbeda dengan lahan sawah atau lahan kering dataran tinggi. Perbedaan tersebut antara lain terlihat dari jenis tanaman yang lebih bervariasi dan pola tanam yang lebih beragam di dataran tinggi. Disamping itu sebagian besar lahan tersebut merupakan lahan marjinal dan curam sehingga sangat peka terhadap erosi. Akibatnya bahan organik banyak tercuci sehingga kesuburan tanah makin menurun.
Pengkajian dilakukan di dua kecamatan yaitu Tamansari dan Tamanjaya, Kabupaten Tasikmalaya pada tahun 2001-2002, melibatkan 3 kelompok tani. Introduksi teknologi yang dilakukan meliputi: perbaikan pola tanam yang mencakup kacang tanah, jagung dan lada perdu. Introduksi ternak domba garut unggul dengan pola 1 jantan dan 8 betina, tanaman pakan ternak (Glyricidia) yang ditanam pada teras bangku dan teras gulud untuk mencegah erosi permukaan dan konservasi tanah, sedangkan untuk peningkatan produktivitas ditanam palawija (kacang tanah, jagung) dan lada perdu.

Tujuan pengkajian untuk mendapatkan model usahatani konservasi, integrasi tanaman-ternak di lahan kering dataran rendah dan meningkatkan pendapatan petani. Hasil pengkajian menunjukkan bahwa tumpangsari lada perdu dengan kacang tanah, baik pada teras bangku maupun teras gulud tingkat erosinya paling kecil yaitu masing-masing 4,15 t/ha dan 4,74 t/ha. Hasil polong kacang tanah rata-rata 946 kg/ha dan hijauan brangkasan 2.090,29 kg/ha sedangkan cara petani menghasilkan rata-rata 261,34 kg/ha.

Ternak domba yang semula hanya diberi pakan rumput lapangan dan daun nangka berubah dengan komposisi hijauan rumput lapangan yang dikombinasikan dengan leguminosa dan ramban. Jumlah induk yang melahirkan tercatat 82,50% dengan rata-rata berat lahir 9,09 kg dan jumlah anak per kelahiran 1,37 ekor. Sedangkan bahan organik yang dihasilkan untuk reklamasi lahan rata-rata 0,59 kg pupuk kandang dan 0,95 sisa pakan per ekor per hari.

Pengembangan Jenis-jenis Pohon yang Bernilai Ekonomi
Dalam Model Agroforestri Berbasis Cendana di Kabupaten Belu, NTT

Ir. Albertus Husein Wawo, M.Si.

Kegitan tebas bakar dan berpindah-pindah ladang yang dilakukan oleh petani lahan kering di kabupaten Belu dan NTT pada umumnya menyebabkan kekurangan pangan, kerusakan lingkungan dan pemborosan penggunaan lahan pertanian. Agroforestri adalah salah satu sistem pengembangan pertanian dengan mengkombinasikan jenis-jenis pohon dan tanaman semusim (pangan) dalam satu unit lahan. Setiap daerah memiliki kekhasan model agroforestri tergantung pada kondisi tanah, iklim dan jenis pohon/hutan yang ada di daerah tersebut. Agroforestri hendaknya memiliki 3 fungsi utama yaitu ekonomi, ekologi dan sosial. Oleh karena itu bagi kabupaten Belu dan NTT pada umumnya model agroforestri yang spesifik adalah model agroforestri berbasis cendana yang disingkat Model ABC. Tanaman cendana (Santalum album) mendapatkan perhatian dalam kegiatan ini karena cendana merupakan tanaman khas NTT yang memiliki nilai ekonomi tinggi dan saat ini terancam punah.

Pada tahun 2002-2003 telah dikembangkan plot-plot percontohan model agroforestri berbasis cendana di daerah dataran tinggi (1000 m dpl) di desa Dirun, Kecamatan Lamaknen seluas 3.0 ha. Pada tahun 2005 pengembangan jenis-jenis pohon yang bernilai ekonomi dalam model ABC dilaksanakan di daerah dataran rendah pada ketinggian 500-600 m dpl di Desa Teun, Kecamatan Raimanuk seluas 1.0 ha sebagai perluasan plot percontohan model ABC pada tahun 2004 yang luasnya 1.5 ha. Sehingga pada akhir tahun 2005 ini total luas plot percontohan model ABC untuk pengembangan jenis-jenis pohon yang bernilai ekonomi di Desa Teun, Raimanuk adalah 2.5 ha.

Dalam Model ABC tersebut selain cendana dibudidayakan juga jenis-jenis pohon yang bernilai ekonomi dan tanaman pangan sehingga produktivitas lahan kering meningkat dan juga melindungi jenis-jenis pohon tersebut dari kepunahan serta mengatasi ketidakpastian panen dari tanaman semusim. Jenis-jenis pohon tersebut selain memiliki nilai ekonomi juga telah beradaptasi dengan kondisi iklim kering. Jenis-jenis tersebut adalah asam, mangga, jambu batu dan sirsak. Sedangkan jenis tanaman pangan yang dibudidayakan pada musim hujan adalah jagung dan kacang gude.

Selain pengembangan plot model ABC, juga telah dilakukan kegiatan optimasi pemanfaatan pekarangan dengan pengembangan sayuran, penanaman cendana dan mangga di pekarangan penduduk. Dengan demikian fungsi pekarangan diperluas menjadi area konservasi flora khas daerah kering.

Selain kegiatan di Desa Teun, Kecamatan Raimanuk telah dilakukan juga perawatan lanjutan dan pengamatan pertumbuhan cendana di Desa Dirun, Kecamatan Lamaknen pada umur 3 tahun menunjukkan pertumbuhan yang berbeda antara cendana yang tumbuh pada tanah miring dan yang tumbuh pada tanah datar. Pada tahun 2005 ditemukan beberapa jenis hama yang agak serius menyerang cendana di desa Dirun, Lakmanen.

Pemeliharaan lanjutan pasca tanam pada tanaman cendana melibatkan masyarakat lokal, sehingga saat ini telah terbentuk 2 kelompok petani pecinta cendana di Desa Teun, Kecamatan Raimanuk.

Selain pengembangan plot-plot percontohan Model ABC, telah dibangun pula kerjasama antara LIPI dan Dinas Kehutanan Kabupaten Belu, untuk membangun Kebun Benih Cendana Kian Rai Ikun seluas 10.0 ha.

Kata Kunci : Model ABC, lahan kering, jenis-jenis pohon bernilai ekonomi, partisipasi masyarakat lokal, penyiraman tetes, Botes-AHW, Kebun Benih, Belu, NTT.

Sekarang pelajari bahan tentang NTT

KEADAAN UMUM NTT

1. KEADAAN FISIK DAERAH
1. Luas dan Letak Goegrafis

Propinsi Nusa Tenggara Timur secara geografis terletak diantara 8°5' - 11°1' Lintang Selatan dan diantara 118°56' - 125°11' Bujur Timur. Di sebelah Utara dibatasi Laut Flores, di sebelah Selatan dibatasi Selat Sape (Propinsi Nusa Tenggara Barat) dan disebelah Timur dibatasi oleh Propinsi Timor-Timur.

Propinsi ini merupakan wilayah Kepulauan, terdiri dari ±566 pulau, diantaranya terdapat 3 gugusan pulau yaitu Flores (Komodo, Rinca, Flores, Solor, Adonara, Lembata) Sumba dan Timor (Sawu, Rote, Semau, Timor, Alor dan Pantar).

Propinsi Daerah Tingkat I Nusa Tenggara Timur mempunyai luas daratan 4.738.920 Ha dan secara administrasi terbagi atas 12 wilayah Kabupaten, 1 Kota Madya, 10 Koordinator Pemerintah Kota (KOPETA), 114 Kecamatan, 47 perwakilan Kecamatan, 172 desa difinitif dan 20 desa persiapan.

2. Keadaan Lapangan/Topografi dan DAS

Keadaan lapangan Propinsi Nusa Tenggara Timur mulai datar sampai sangat curam dengan bentuk daratan sampai sangat bergunung. Topografi datar (lereng 0-8%) seluas ±1.265.196 Ha (26,51% dari luas wilayah), landai (lereng 8-15%) seluas ±1.174.366 Ha (24,78%), agak curam (lereng 15-25%) seluas ±1.409.765 Ha (29,75%), curam (lereng 25-45%) seluas ±132.425 Ha (2,79%).

Pada topografi datar terdapat beberapa daratan yang cukup luas antara lain di Pulau Flores terdapat daratan Lembor, Borong, Aimere, dan Aisesa, di Pulau Sumba terdapat daratan Waikabubak, Anakalang dan Lewa, di Pulau Timor terdapat daratan Oesao, Bokong, Bena, Ponu, Aroki dan Besikama.

Beberapa gunung yang ada di Pulau Flores antara lain Gunung Ranaka (2.400 m dari permukaan laut, tertinggi di Pulau Flores), Mandosaawu (2.382 m), Inerie (2.245 m), Guteng (2.216) m), Ambulembo (2.149 m). Di Pulau Sumba antara lain Gunung Wanggameti (1,225 m dari permukaan laut, tertinggi di Pulau Sumba), Anajeke (1.172 m), Iwing (1.605 m), Kabaau (1.051) ) dan Pahulubandil (1.050 m). Di Pulau Timor antara lain terdapat Gunung Mutis (2.427 m dari permukaan laut, tertinggi di Pulau Timor dan di Nusa Tenggara Timur), Nefomat (2.251) m), Kekneno (2.070) m), Wehaf (1.966 m), Timau (1.774 m). Di Pulau Alor antara lain terdapat Gunung Muna (1.423 m dari permukaan laut), Apengmana (1.378 m), Blikmana (1.354 m) dan Fokala (1.331 m).

Sungai yang terdapat di Propinsi Nusa Tenggara Timur pada umumnya mempunyai fluktuasi aliran air yang cukup tinggi, pada musim penghujan berair dan banjir, sedangkan pada musim kemarau berkurang bahkan ada yang tidak berair sama sekali.

Sungai-sungai yang ada di Pulau Flores antara lain Sungai Aisesa (65 km, terpanjang di Flores), Reo (55 km), Moke (45 km), Leo Ria (40 Km) dan Jamal (40 Km). Di Pulau Sumba antara lain terdapat sungai Kambaniru (118 Km, terpanjang di Pulau Sumba), Kadaha (46 Km), Melolo (51 Km), Baing (48 Km) dan Kalada (46 Km). Di Pulau Timor antara lain terdapat Sungai Benain (135 Km, terpanjang di Pulau Timor dan di Nusa Tenggara Timur), Mina (97 Km), Termanu (51 Km), Muke (45 Km) dan Mena (33 Km).

Berdasarkan pola daerah aliran sungai yang dibatasi garis-garis gunung, maka wilayah Nusa Tenggara Timur terbagi atas 509 Daerah Aliran Sungai (DAS). Di Pulau Flores antara lain terdapat DAS Aesessa (Luas ±122.000 Ha), DAS Reo (±94.000 Ha), DAS Jamal (±80.000 Ha) dan DAS Buntal (± 40.000 Ha).

Di Pulau Sumba antara lain terdapat DAS Kambaniru (±111.000 Ha), DAS Kanatang (±51.000 Ha), DAS Kadaha (±40.000 Ha), DAS Tidas (±33.000 Ha) dan DAS Nggongi (± 26.000 Ha).

Di Pulau Timor antara lain terdapat DAS Benain (±241.000 Ha), DAS Tarus (±210.000 Ha) dan DAS Naitlopen (±36.000 Ha).

3. T a n a h

Keadaan formasi tanah di Wilayah Propinsi Nusa Tenggara Timur secara garis besar adalah sebagai berikut:

1. Pulau Flores dan sekitarnya

Tanah di Pulau Flores terdiri dari jenis tanah mediteran dengan bentuk wilayah Volkan, tanah Kompleks dengan bentuk wilayah pegunungan, kompleks Latosol dengan bentuk wilayah Volkan, Alluvial dengan bentuk wilayah dataran. Tanah-tanah Mediteran dengan bentuk wilayah Volkan mempunyai penyebaran yang paling luas. Pulau Lembata Adonara dan Solor mempunyai tanah jenis Mediteran dengan bentuk Volkan.

2. Pulau Sumba

Tanah di Pulau Sumba terdiri dari jenis mediteran dengan bentuk wilayah pengunungan lipatan dan datar serta bentuk wilayah volkan. Latosol dan Grumusol dengan bentuk wilayah pelembahan.

Tanah Mediteran dengan bentuk wilayah pengunungan lipatan adalah merupakan jenis tanah yang paling luas penyebarannya.

3. Pulau Timor dan sekitarnya

Jenis tanah di Pulau Timor adalah tanah-tanah kompleks dengan bentuk wilayah pengunungan kompleks, mediteran dengan bentuk wilayah lipatan, Grumusol dengan bentuk wilayah dataran, Latosol dengan bentuk wilayah plato/Volkan. Tanah-tanah kompleks dengan bentuk wilayah pengunungan kompleks merupakan jenis tanah yang paling luas penyebarannya. Pulau Alor dan Pantar mempunyai jenis tanah Mediteran bentuk tanah Volkan.

Berdasarkan penyebarannya, maka prosentasi jenis-jenis tanah di wilayah Nusa Tenggara Timur antara lain terdiri dari tanah Mediteran ±51%; tanah-tanah kompleks ±32,25%; Latosol ±9,72%; Grumusol ±3,25%; Andosol ±1,93%; Regosol ±0,19% dan jenis tanah Aluvial ±1,66% (Sumber Rencana Umum Kehutanan Propinsi Dati I Nusa Tenggara Timur tahun 1987).

4. I k l i m

Propinsi Nusa Tenggara Timur beriklim kering (Semi arid) yang dipengaruhi oleh Angin Muson. Musim penghujan sangat pendek dan terjadi antara bulan Nopember sampai bulan Maret, Sedangkan Musim Kemarau panjang dan kering terjadi pada bulan April sampai dengan bulan Oktober.

Tipe iklim daerah ini adalah tipe B sampai F (pembagian menurut Smidt dan Ferguson) dengan penyebaran paling luas adalah tipe iklim E (46,34%); F (27,37%); D (22,93%); B (2,30%) dan C (1,05%).

Curah hujan berkisar antara 697 - 2.737 mm/tahun dengan jumlah hari hujan rata-rata tiap tahun antara 44 sampai 61 hari. Suhu maksimum rata-rata 33,2°C dan suhu minimum rata-rata 21,7°C. Kelembaban nisbi terendah terjadi pada Musim Timur Tenggara (63-76%) yaitu bulan Juni sampai Nopember dan kelembaban tertinggi pada Musim Barat Daya (82-88%) yaitu bulan Desember sampai bulan Mei.

Kecepatan angin rata-rata pada Bulan Nopember sampai April 03-05 Knot dan Angin Musim Timor Tenggara terjadi pada bulan mei sampai dengan Oktober dengan kecepatan dapat mencapai 06-10 Knot (apabila ditunjang angin permukaan).

5. Kemampuan Wilayah

Atas dasar keadaan bentuk lapangan, keadaan tanah dan iklimnya dapat diketahui bahwa wilayah Propinsi Dati I Nusa Tenggara Timur merupakan wilayah dengan kemampuan sedang (kelas IV) sampai jelek sekali (kelas VI), menurut klasifikasi kemampuan wilayah oleh Soepraptohardjo (1970).

Lahan yang cocok bagi usaha pertanian pangan semusim terbatas sekali ±1.697.000 Ha atau ±36% dan itupun harus dilakukan dengan investasi yang besar seperti pemupukan dan disertai usaha-usaha konservasi tanah antara lain terassering. Lahan selebihnya ±3.038.000 Ha atau 64% adalah lahan yang harus dimanfaatkan untuk usaha tanaman keras dan hutan (Hutan Lindung, Produksi dan Hutan lainnya), disamping usaha peternakan.

Secara rinci luas lahan berdasrkan kemampuan wilayah di Propinsi Dati I NTT adalah kelas sedang seluas 1.697.000 Ha atau 36% terletak menyebar di Kepulauan Flores dan Sumba.

Kelas agak jelek juga seluas 1.697.000 Ha atau 36% terdapat di wilayah Pulau Timor, Flores dan Sumba. Kelas jelek seluas 310.000 Ha atau 6,56% terdapat di wilayah Pulau Flores dan Sumba. Kelas jelek sekali seluas 1.031.000 Ha atau 21% tersebar di wilayah Pulau Timor.

6. Penggunaan Lahan

Lahan di Propinsi Dati I Nusa Tenggara Timur sebagian besar berupa lahan kering (96,92%), sedangkan sisanya seluas 145.705 (3,08%) adalah lahan basah, antara lain 110 Ha (0,01%) dan penggunaan lainnya seluas 3.736 Ha (0,08%).

Dari seluruh luas lahan yang ada baru 2.565.018 Ha atau 54,17% yang telah diusahakan, yaitu berupa sawah seluas 141.859 Ha, tegalan seluas 333.493 Ha, ladang seluas 291.417 Ha, tambak 3.335 Ha dan kolam seluas 2.237 Ha, Hutan Negara seluas 857.502, pekarangan tanah bangunan dan alam sekitarnya seluas 141.344 Ha, Perkebunan Negara/swasta seluas 280.369 Ha dan tanaman kayu-kayuan/hutan rakyat seluas 513.462 Ha. Sisanya seluas 2.169.972 Ha adalah tanah pengembalaan/padang rumput seluas 653.983 Ha, tanah sementara tidak diusahakan seluas 1.928 Ha serta lain-lain seluas 819.290 Ha (Sumber data : Nusa Tenggara Timur dalam angka tahun 1995).

7. Luas Hutan

Berdasarkan Keputusan Gubernur Kepala Daerah Propinsi Dati I Nusa Tenggara Timur No. 46 Tahun 1996, tentang Penetapan Hasil Paduserasi Rencana Tata Ruang Wilayah Propinsi dan TGHK, maka luas kawasan hutan menjadi 1.808.981,27 Ha dan berdasarkan fungsinya dapat diperinsi sebagai berikut:

1. Kawasan Lindung seluas 1.081.546,53 Ha yang terdiri dari : Hutan Lindung seluas 731.216,97 Ha; Cagar Alam seluas 66.653,25 Ha; Suaka Marga Satwa seluas 18.916,81 Ha; Pantai Hutan Bakau seluas 40.695,54 Ha; Taman Nasional seluas 59.058,53 Ha; Taman Buru seluas 5.850,67 Ha dan Taman Wisata seluas 159.154,76 Ha.
2. Kawasan Budidaya seluas 727.434,74 Ha yang terdiri : Hutan Produksi Terbatas seluas 197.249,73 Ha; Hutan Produksi Tetap seluas 428.357,98 Ha dan Hutan Produksi yang dapat dikonversi seluas 101.827,03 Ha.

2. KEADAAN SOSIAL EKONOMI
1. Penduduk

Propinsi Nusa Ternggara Timur dengan luas wilayah daratan 47.389,2 Km2, pada tahun 1995 berpenduduk sebanyak 3.439.450 jiwa yang terdiri dari laki-laki sebanyak 1.698.645 orang dan perempuan 1.740.805 orang. Laju pertumbuhan penduduk 1980 sampai dengan 1990 rata-rata sebesar 1,79% termasuk di Flores (0,31%) dan tertinggi di Kupang 2,64%. Jumlah rumah tangga yang ada sebanyak 651.939 KK dengan rata-rata jumlah 5-6 orang tiap rumah tangga dan dengan kepadatan penduduk rata-rata 73 orang/Km2.

Prosentase angkatan kerja pada tahun 1995 di Propinsi Nusa Tenggara Timur adalah sebanyak 67,10% dengan perincian : bekerja 65,69% dan mencari pekerjaan 1,41%.

Berdasarkan agama, maka penduduk Nusa Tenggara Timur mayoritas beragama Kristen. Penganut agama Kristen Katolik sebanyak 1.866.858 orang (54,28%), Kristen Protestan 1.124.113 orang (32,68%), Islam sebanyak 306.131 orang (8,90%), Hindu sebanyak 7.971 orang (0,23%), Budha sebanyak 695 orang (0,20%) dan kepercayaan lainnya sebanyak 133.682 orang (3,89%).

2. Pendidikan

Tingkat pendidikan rata-rata penduduk di Propinsi Nusa Tenggara Timur masih relatif rendah yaitu : 29,34%; terutama SD 7,59%; tamatan SLTP 7,50%; tamatan SLTA 1,69%; tamatan Akademi/Diploma/Universitas 36,72% dan belum tamat SD 17,16% tidak/belum termasuk sekolah.

Sarana dan Prasarana pendidikan terdiri dari : 3.956 buah SD, 531 buah SMTP, 189 buah SMTA, dan 16 buah Perguruan tinggi. Jumlah tenaga pengajar sebanyak 40.870 orang yang terdiri dari 38.868 orang guru dan 2.002 orang dosen.

3. Kesehatan

Jenis sarana, prasarana dan tenaga kesehatan yang ada di Propinsi Nusa Tenggara Timur terdiri : 24 buah rumah sakit, 1.715 tempat tidur, 274 orang dokter, 1.893 orang perawat, 1-904 orang bidan dan para medis.

Banyaknya klinik dan peserta KB serta PUS terdiri dari : 219 buah krinik KB yang melayani 329.807 orang peserta KB dan 529.150 orang pasangan usia subur (PUS).

Banyaknya akseptor aktif berdasarkan metode kontrasepsi yang digunakan terdiri dari : 92.848 IUD, 40.135 PIL, 2339 kondom, dan 20.639 medio operatif.

4. Mata Pencaharian dan Pendapatan Penduduk

Penduduk Propinsi Nusa Tenggara Timur sebagian besar (78,02%) mengantungkan hidupnya pada bidang pertanian baik sebagai petani, peternak maupun nelayan, sedangkan prosentase penduduk yang bekerja di luar sektor pertanian sebesar 21,98%; dengan rincian : 9,78% jasa kemasyarakatan; 5,04% industri pengolahan; 4,05% pedagang besar/eceran dan rumah makan; 1,33% bangunan; 0,87% angkutan, pengudangan dan komunikasi; 0,36% pertambangan dan penggalian; 0,17% keuangan, asuransi, usaha persewaan dan bangunan; 0,13% listrik, gas dan air serta 0,25% kegiatan lainnya.

Rata-rata pendapatan perkapita penduduk Propinsi Nusa Tenggara Timur atas dasar harga yang berlaku tahun 1995 sebesar Rp. 785.281 (angka sementara), dimana pendapatan perkapita terendah terjadi di Kabupaten Sumba Barat (Rp. 559.932,-) dan tertinggi terjadi di Kupang (Rp. 1.386.480,-).

Rata-rata pertumbuhan ekonomi di Propinsi Nusa Tenggara Timur sebesar 8,86%, angka terendah terjadi di Kabupaten Sumba barat (2,49%) dan tertinggi di Kupang (13,62%).

5. Pertanian

Para petani di Propinsi Nusa Tenggara Timur sebagian besar adalah petani lahan kering dengan pola perladangan berpindah dan hanya sebagian kecil merupakan petani lahan basah. Kegiatan pertanian tersebut terdiri dari sub sektor tanaman pangan, perkebunan, peternakan dan kehutanan.

Luas panen, rata-rata hasil dan produksi tanaman pangan tahun 1995 dapat dilihat pada tabel di bawah ini:

No.	Komoditas	Luas Panen (Ha)	Produktifitas (Kw/Ha)	Produksi (Ton)
1	Padi	159.825	26,27	419.929
2	Jagung	254.126	16,38	416.362
3	Ubi Kayu	81.561	101,79	830.240
4	Ubi Jalar	11.955	78,06	93.315
5	Kacang Tanah	10.543	8,48	8.938
6	Kacang Kedelai	5.672	7,30	4.108

Sumber Data : NTT dalam Angkat 1995

Luas areal perkebunan di Nusa Tenggara Timur sampai dengan tahun 1995 mencapai 485.645 Ha dengan produksi mencapai 86.044 Ton yang terdiri dari jenis komoditas perkebunan : kelapa, kopi, cengkeh, coklat, jambu mente, kemiri, kapok, jeruk, vanili, pala, pinang dan tembakau.

Sistem berternak di Propinsi Nusa Tenggara Timur sebagian besar masih dilakukan secara tradisional yaitu dengan cara dilepas, sistem ini membawa dampak terhadap kerusakan lahan dan vegetasi sehingga ada kecenderungan meluasmnya lahan kritis.

Jumlah ternak di Propinsi Nusa Tenggara Timur tahun 1995 tercatat sebanyak 11.502.407 ekor yang dengan rincian sebagai berikut:

1. Termasuk besar sebanyak 1.134.584 ekor yang terdiri : 803.357 ekor sapi, 167.239 ekor kerbau, dan 163.988 ekor kuda.
2. Ternak kecil sebanyak 2.253.227 ekor yang terdiri dari : 1.524.184 ekor babi dan 729.043 ekor kambing/domba.
3. Ternak unggas sebanyak 8.144.596 ekor yang terdiri dari : 7.122.951 ekor ayam kampung, 805.249 ekor ayam ras dan 186.396 ekor itik.

Kegiatan usaha perikanan di Propinsi Nusa Tenggara Timur masih didominasi perikanan laut.

Jumlah Rumah Tangga (RT) usaha perikanan laut berdasarkan katagori usaha terdiri dari : 5.304 RT tanpa perahu, 14.968 RT perahu tanpa motor, 730 RT perahu motor tempel dan 836 RT kapal motor.

Kegiatan perikanan di Propinsi Nusa Tenggara Timur selama tahun 1995 dapat menghasilkan ikan sebanyak 64.873,5 ton yang terdiri dari : 64.169,50 ton perikanan laut dan 704 ton perikanan darat.

Jumlah Rumah Tangga (RT) yang terkait pada sektor perikanan sebanyak 31.753 RT yang terdiri dari 21.838 RT di perikanan laut dan sebanyak 9.915 RT di perikanan darat.

Produksi hasil hutan kayu terdiri dari :

• 18.928,207 M2 kayu yang terdiri dari kayu rimba dan jati
• 187.616,00 Kg kayu kuning, kayu manis, gaharu dan arang
• 246,114 Ton kayu cendana
• 8.038,00 M3 balok tuak

Produksi Hasil hutan Non kayu terdiri dari :

• 15.589,5 Ton asam dan kemiri
• 79.115,00 Kg siri hutan, pinang iris, lilin, kunyit, kulit kayu manis, rotan dan kencur
• 2.0491,00 liter madu
5. Perhubungan

Sarana dan prasarana perhubungan yang ada di Propinsi Nusa Tenggara Timur meliputi sarana dan prasarana perhubungan darat, laut dan udara.

Sarana dan prasarana perhubungan darat meliputi jumlah kendaraan dan panjang jalan. Jumlah kendaraan sampai dengan tahun 1995 di Propinsi Nusa Tenggara Timur mencapai 72.829 buah yang terdiri dari 48.830 buah Sepeda Motor, 8.282 buah Jeep-Sedan-Salon Station Wagon, 6.213 buah Mikro Bis/Minibis, 9.504 buah Truk/Pick up/Light Truk/Tanki/Traktor.

Sedangkan panjang jalan mencapai 15.262,43 Km yang terdiri dari 1.184,99 Km jalan Negara; 3.179,94 Km jalan Propinsi dan 10.897,50 Km jalan Kabupaten.

Kegiatan pelayanan perhubungan udara di 14 lokasi pelabuhan udara selama tahun 1995 adalah sebagai berikut:

• Jumlah pesawat datang sebanyak 9.408 kali dengan jumlah penumpang 171.590 orang
• Jumlah pesawat berangkat sebanyak 9.413 kali dengan jumlah penumpang 170.946 orang

Kegiatan pelayanan perhubungan laut di 14 lokasi pelabuhan laut selama tahun 1995 adalah sebagai berikut:

• Jenis pelayaran : Samudera, Nusantara, Lokal dan khusus sebanyak 1.576 kali
• Jenis pelayaran perintis sebanyak 597 kali
• Jenis pelayaran rakyat sebanyak 1.197 kali

Sedangkan arus penumpang kapal laut selama tahun 1995 yang naik sebanyak 336.511 orang dan yang turun sebanyak 370.032 orang.

Arus kunjungan angkutan penyeberangan feri di 6 pelabuhan laut menunjukkan sebanyak 3.748 kali arus kunjungan dengan jumlah penumpang sebanyak 236.218 orang.

7. Perdagangan

Jumlah perusahaan/usaha sektor perdagangan sampai dengan tahun 1995 di Propinsi Nusa Tenggara Timur mencapai 10.372 buah yang terdiri dari 376 buah perdagangan besar, 4.409 buah perdagangan menengah dan 5.587 buah perdagangan kecil.

Neraca perdagangan luar negeri Propinsi Nusa Tenggara Timur selama tahun 1994 mengalami surplus sebesar US$ 17.893.000 dan nilai impor mencapai US$ 6.857.000. Begitupun juga tahun 1995 neraca perdaganggan luar negeri surplus sebesar US$ 13.094.000 dan nilai ekspor mencapai US$ 16.514.000 dan nilai impor mencapai US$ 3.420.000.

Volume dan nilai ekspor Nusa Tenggara Timur selama tahun 1995 terdiri dari 14.554.629 ton volume ekspor dengan nilai ekspor sebesar US$ 16.514.258.

8. Pertambangan dan Industri

Peranan sektor pertambangan di Propinsi Nusa Tenggara Timur sampai saat ini belum menunjukkan prospek yang mengembirakan untuk menyerap tenaga kerja dan meningkatkan pendapatan masyarakat, walaupun di Propinsi Nusa Tenggara Timur memiliki potensi pertambangan di masa mendatang cukup baik, potensi tambang tersebut berupa:

• Mangan, emas dan tembaga di kecamatan Molo Utara, Amanuban Tengah, Amanuban Selatan (Kabupaten TTS) dan Kecamatan Sabu Timur (Kabupaten Kupang)
• Tembaga di Kecamatan Tasifeto Barat (Kabupaten Belu) umumnya lokasi potensi pertambangan tersebut berada di kawasan hutan.

Kegiatan industri yang berada di Propinsi Nusa Tenggara Timur berupa industri pengolahan dan kerajinan. Banyaknya industri/pengrajin sampai dengan tahun 1995 terdiri dari:

• 43 buah perusahaan industri besar yang mampu menyerap tenaga kerja sebanyak 2.006 orang
• 64.630 buah perusahaan industri kecil/pengrajin yang mampu menyerap tenaga kerja sebanyak 95.209 orang
8. Pariwisata dan Perhotelan/Losmen

Potensi Obyek wisata alam/ekotourisme di Propinsi Nusa Tenggara Timur cukup besar antara lain:

• Danau Tiga Warna Kelimutu (Kabupaten Ende)
• Binatang purba Komodo (Kabupaten Manggarai)
• Taman Laut 17 Pulau Riung (Kabupaten Ngada)
• Taman Laut Teluk Maumere (Kabupaten Sikka)
• Taman Laut Teluk Kupang (Kabupaten Kupang)
• Hutan Wisata Camplong (Kabupaten Kupang)
• Taman Hutan Raya Prof. Ir. Hermas Johanes (Kabupaten Kupang)
• Peninggalan Sejarah, budaya dan obyek wisata alam lainnya
• Tenun ikat tradisional

Dengan adanya obyek wisata alam tersebut diatas telah menarik wisata asing untuk datang ke Nusa Tenggara Timur, selama tahun 1994 wisatawan asing yang datang sebanyak 61.812 orang dan tahun 1995 sebanyak 71.879 orang (naik 16,29%).

Untuk meningkatkan pelayanan wisata alam di Nusa Tenggara Timur baik lokal maupun asing telah berkembang perusahaan penginapan berupa Hotel/Losmen. Jumlah hotel/losmen sampai dengan tahun 1995 mencapai 181 buah yang dapat menyediakan kamar tidur sebanyak 2.588 buah dan sebanyak 5.437 tempat tidur.

10. Pos dan Telekomunikasi

Sarana dan prasarana telekomunikasi yang ada di Nusa Tenggara Timur sampai dengan tahun 1995 berupa 12 unit kantor pos, 6 unit kantor pos tambahan, 54 kantor pos pembantu dan 20 unit pos desa.

Sedangkan pelayanan pos yang telah dilaksanakan adalah pengiriman paket pos dan surat. Pengiriman paket pos selama tahun 1995 sebanyak 588.108 Kg dan pengiriman surat sebanyak 3.236.100 buah surat yang terdiri dari 2.015.900 buah surat biasa, 1.123.000 buah surat kilat dan 97.200 buah surat tercatat.

Jumlah pelanggan telepon sampai dengan tahun 1995 pemerintah sebanyak 2.156 satuan sambungan dan swasta sebanyak 13 satuan sambungan.

11. Listrik dan Air Minum

Kegiatan pelayanan listrik di Propinsi Nusa Tenggara Timur memperlihatkan data sebagai berikut:

• Jumlah pelanggan sebanyak 129.484 unit
• Jumlah pemakaian strum sebanyak 113.566.887 KWH

Sedangkan pelayanan air minum selama tahun 1995 memperlihatkan data sebagai berikut:

• Jumlah pelanggan sebanyak 37.904 unit
• Jumlah pemakai sebanyak 11.163.477 M3
11. Koperasi dan Perbankan

Jumlah koperasi di Propinsi Nusa Tenggara Timur sampai dengan tahun 1995 mencapai 800 unit yang terdiri dari 151 unit KUD dan 649 unit koperasi lainnya. Dari 151 unit KUD memiliki jumlah anggota sebanyak 178.049 orang dan dari 649 unit koperasi lainnya memiliki anggota sebanyak 86.184 orang.

Jumlah sarana dan prasarana pelayanan perbankan di Propinsi Nusa Tenggara Timur sampai dengan tahun 1995 terdiri dari : 1 unit Kanwil, 1 unit Kantor Pusat, 32 unit Kantor Cabang, 17 unit Kantor Cabang Pembantu dan 1 unit Kantor Kas.

Jumlah Kantor Bank sebanyak 52 unit yang terdiri dari : 14 unit BRI, 11 unit BPD, dan 27 unit Bank lainnya.

Jumlah penabung sampai dengan tahun 1995 sebanyak 707.129 orang/nasabah dengan posisi : tabungan Rp. 312.796.000,- kredit Rp. 279.390.000.-

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Tugas: buatkan esai tentang model pengembangan peternakan lahan kering apa yang paling sesuai untuk diterapkan di NTT. Tiap-tiap orang membuat 1 buah esai yang bebas memilih judulnya. Judul esai HARUS dilaporkan kepada saya melalui kotak komentar di blog: bigmike-savanna land.blogspot.com (harap mengisi nama, NIM dan judul esai).

Setelah esai dibuat maka kirimkan ke alamat e-mail: makati24@gmail.com.
Saya tidak menerima hard copy/print out.

Hasil penilaian dapat dilihat di blog: makati24.blogspot.com (tidak saya sebutkan nama cuma NIM)

DR. Ir. L. Michael Riwu Kaho, M.Si
NIP. 131 660 815

Bahan kuliah PR (4): Rangeland

Rangeland refers to expansive, mostly unimproved lands on which a significant proportion of the natural vegetation is native grasses, grass-like plants, forbs, and shrubs. Rangeland also consists of areas seeded to native or adapted introduced species that are managed like native vegetation. Rangelands include natural grasslands, savannas, shrublands, many deserts, tundra, alpine communities, coastal marshes, and wet meadows. Rangeland is generally arid, semi-arid, sub-humid or otherwise unsuitable for cultivation.

arid

In general terms, the climate of a locale or region is said to be arid when it is characterized by a severe lack of available water, to the extent of hindering or even preventing the growth and development of plant and animal life. As a result, environments subject to arid climates tend to lack vegetation and are called xeric or desertic.

Semi arid

Semi-arid climate or steppe climate generally describes climatic regions that receive low annual rainfall (250-500 mm or 10-20 in). A more precise definition is given by the Köppen climate classification that treats steppe climates (BS) as intermediates between the desert climates (BW) and humid climates in ecological characteristics and agricultural potential. The Köppen climate classification allows adjustments for temperature and for seasonality of precipitation, effectively excluding forested regions (such as those in most of Canada and Siberia)

Tillage

Tillage, or cultivation is the agricultural preparation of the soil by digging it up. Tillage can also mean the land that is tilled the process of fostering the growth of something; "the cultivation of bees for honey" : the act of raising or growing plants (especially on a large scale) The process of promoting the growth of a biological culture.

Tillage systems

intensive tillage

Intensive tillage systems leave less than 15% crop residue cover or less than 500 pounds per acre (560 kg/ha) of small grain residue. These types of tillage systems are often referred to as conventional tillage systems but as reduced and conservation tillage systems have been more widely adopted, it is often not appropriate to refer to this type of system as conventional. These systems involve often multiple operations with implements such as a mold board plow, disk, and/or chisel plow. After Moldboard plowing, a disk is often used to break clods. Then a a finisher .....with a harrow, rolling basket, and cutter head can be used ..... can be used to prepare the seed bed. There are many variations.

Reduced tillage

Reduced tillage systems leave between 15 and 30% residue cover on the soil or 500 to 1000 pounds per acre (560 to 1100 kg/ha) of small grain residue during the critical erosion period. This may involve the use of a chisel plow, field cultivators, or other implements. See the general comments below to see how they can effect the amount of residue.

Conservation tillage

Conservation tillage systems are methods of soil tillage which leave a minimum of 30% of crop residue on the soil surface or at least 1,000 lb/ac (1,100 kg/ha) of small grain residue on the surface during the critical soil erosion period. This slows water movement, which reduces the amount of soil erosion; it also warms the soil, enabling the next year’s crop to be planted earlier in the spring. Conservation tillage systems also benefit farmers by reducing fuel consumption and soil compaction. By reducing the number of times the farmer travels over the field, farmers realize significant savings in fuel and labor. Conservation tillage was used on about 38%, 109,000,000 acres (440,000 km²), of all US cropland, 293,000,000 acres (1,190,000 km²) planted as of 2004 according to the USDA.

• No-till
• Strip-Till
• Mulch-Till
• Ridge-Till

Definitions

Primary tillage loosens the soil and mixes in fertilizer and/or plant material, resulting in soil with a rough texture.

Secondary tillage produces finer soil and sometimes shapes the rows. It can be done by a using various combinations of equipment: plough, disk plough, harrow, dibble, hoe, shovel, rotary tillers, subsoiler, ridge or bed forming tillers, roller.

Weed plants (seeds, tubers, etc.) may be exhausted by repeated tilling. The weeds expend energy to reach the surface, and then get turned into the soil by tilling. The cycle is repeated until the weeds are dead.

History of tilling

Tilling was first performed via human labor, sometimes involving slaves. Hoofed animals could also be used to till soil via trampling. The wooden plough was then invented. It could be pulled by mule, ox, elephant, water buffalo, or similar sturdy animal. Horses are generally unsuitable, though breeds such as the Clydesdale could work. The steel plough allowed farming in the American Midwest, where tough prairie grasses and rocks caused trouble. Soon after 1900, the farm tractor was introduced, which eventually made modern large-scale agriculture possible.

alternatives to tilling

Modern agricultural science has greatly reduced the use of tillage. Crops can be grown for several years without any tillage through the use of herbicides to control weeds, genetically modified crops that tolerate packed soil, and equipment that can plant seeds or fumigate the soil without really digging it up. This practice, called no-till farming, reduces costs and environmental change by reducing soil erosion and diesel fuel usage (although it does require the use of pesticides). Most organic farming tends to require extensive tilling, as did most farming throughout history, although researchers are investigating farming in polyculture that would eliminate the need for both tillage and pesticides, such as no-dig gardening.

In the United States, around 399 million acres (1,610,000 km²) of rangeland are privately owned. The Bureau of Land Management manages about 167 million acres (676,000 km²) of publicly owned rangeland, with the United States Forest Service managing approximately 95 million acres (380,000 km²) more. Ranchers may lease portions of this public rangeland and pay a fee based on the number and type of livestock and the period for which they are on the land. Many western states have open range laws. In these states, all land, both public and private, is designated as open range unless it is within city limits. In open range, it becomes the responsibility of the land owner to keep unwanted livestock off their land and the livestock owner is not liable for any damage caused by the livestock.

In Kenya, Rangelands make up for 75% of the land surface area,and are largely inhabited by nomadic pastrolists who are largely dependent on livestock. This movement often brings along an incursion of different diseases with the common one being the rinderpest virus in the Kenyan wildlife population from the Somalian ecosystem.

Rangeland is a prominent feature of rural Canada. A provincial jurisdiction, administration and policy regarding range use varies across the country. Like many Commonwealth countries, public tenures on crown land for the purpose of range activities is common in geographically compatible areas. Reconciling the economic needs of ranchers and the need for environmental conservation is one of the primary themes in modern range discourse.

In Australia, pastoral leases may be held over crown land and beef cattle or sheep grazed on large holdings called Sheep stations or Cattle stations.

The Society for Range Management (rangelands.org) is an international organization of natural resource scientists, researchers, educators, land management agency officials, and public and private land managers devoted to the conservation and sustainable stewardship of the world's diverse rangelands. The Society is open to anyone engaged in or interested in any aspect of the study, management, or use of rangelands, and publishes both a scientific journal, Rangeland Ecology and Management, and Rangelands, a journal of practical applied ecology, perspective and contemporary rangelands issues.

Bahan kuliah PR (3): Savanna

savanna or savannah is a grassland ecosystem with scattered trees or shrubs. In savannas trees are small or widely spaced so that the canopy does not close. It is often believed that savannas are characterized by widely spaced, scattered trees, however in many savanna communities tree densities are higher and trees are more regularly spaced than in forest communities. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.^[1] Savannas are also characterised by seasonal water availability, with the majority of rainfall being confined to one season of the year. Savannas can be associated with several types of biomes. Savannas are frequently seen as a transitional zone, occurring between forest and desert or prairie.

Although the term savanna is believed to have originally come from a Native American word describing "land which is without trees but with much grass either tall or short" (Oviedo y Valdes, 1535), by the late 1800s it was used to mean "land with both grass and trees". It now refers to land with grass and either scattered trees or an open canopy of trees.

Threats to savannas

Changes in fire management

Savannas are subject to regular fires and the ecosystem appears to be the result of human use of fire. For example Native Americans created subtropical savannas by periodic burning in some areas of the US southeastern coast where fire-resistant Longleaf Pine was the dominant species.^[2] Aboriginal burning appears to have been responsible for the widespread occurrence of savanna in tropical Australia and New Guinea^[3] and savannas in India are a creation of human fire use.^[4] The maquis shrub savannas of the Mediterranean region were likewise created and maintained by anthropogenic fire.^[5]

These fires are usually confined to the herbaceous layer and do little long term damage to mature trees. However, these fires do serve to either kill or suppress tree seedlings, thus preventing the establishment of a continuous tree canopy which would prevent further grass growth. Prior to European settlement aboriginal land use practices, including fire, influenced vegetation^[6] and may have maintained and modified savanna flora.^[7][8] It has been suggested by many authors^[9][6] that aboriginal burning created a structurally more open savanna landscape. Aboriginal burning certainly created a habitat mosaic that probably increased biodiversity and changed the structure of woodlands and geographic range of numerous woodland species.^[6][10] It has been suggested by many authors^[9][11] that with the removal or alteration of traditional burning regimes many savannas are being replaced by forest and shrub thickets with little herbaceous layer.

The consumption of herbage by introduced grazers in savanna woodlands has led to a reduction in the amount of fuel available for burning and resulted in fewer and cooler fires.^[12] The introduction of exotic pasture legumes has also led to a reduction in the need to burn to produce a flush of green growth because legumes retain high nutrient levels throughout the year, and because fires can have a negative impact on legume populations which causes a reluctance to burn.^[13]

Grazing and browsing animals

The closed forests types such as broadleaf forests and rainforests are usually not grazed owing to the closed structure precluding grass growth, and hence offering little opportunity for grazing.^[14] In contrast the open structure of savannas allows the growth of a herbaceous layer and are commonly used for grazing domestic livestock.^[15] As a result much of the world's savannas have undergone change as a result of grazing by sheep, goats and cattle, ranging from changes in pasture composition to woody weed encroachment.^[16]

The removal of grass by grazing affects the woody plant component of woodland systems in two major ways. Grasses compete with woody plants for water in the topsoil and removal by grazing reduces this competitive effect, potentially boosting tree growth.^[17] In addition to this effect the removal of fuel reduces both the intensity and the frequency of fires which may control woody plant species.^[18] Grazing animals can have a more direct effect on woody plants by the browsing of palatable woody species. There is evidence that unpalatable woody plants have increased under grazing in savannas.^[19] Grazing also promotes the spread of weeds in savannas by the removal or reduction of the plants which would normally compete with potential weeds and hinder establishment.^[6] In addition to this cattle and horses are implicated in the spread of the seeds of weed species such as Prickly Acacia (Acacia nilotica) and Stylo (Stylosanthes spp.).^[20] These alterations in savanna species composition brought about by grazing can alter ecosystem function, and are exacerbated by overgrazing and poor land management practices.

Introduced grazing animals can also affect soil condition through physical compaction and break-up of the soil caused by the hooves of animals and through the erosion effects caused by the removal of protective plant cover. Such effects are most likely to occur on land subjected to repeated and heavy grazing.^[21] The effects of overstocking are often worst on soils of low fertility and in low rainfall areas below 500 mm, as most soil nutrients in these areas tend to be concentrated in the surface so any movement of soil can lead to severe degradation. Alteration in soil structure and nutrient levels affects the establishment, growth and survival of plant species and in turn can lead to a change in woodland structure and composition.

Tree clearing

Large areas of savanna have been cleared of trees, and this clearing is continuing today. For example until recently 480,000 ha of savanna were cleared annually in Australia alone primarily to improve pasture production.^[6] Substantial savanna areas have been cleared of woody vegetation and much of the area that remains today is vegetation that has been disturbed by either clearing or thinning at some point in the past.

Clearing is carried out by the grazing industry in an attempt to increase the quality and quantity of feed available for stock and to improve the management of livestock. The removal of trees from savanna land removes the competition for water from the grasses present, and can lead to a two to fourfold increase in pasture production, as well as improving the quality of the feed available.^[22] Since stock carrying capacity is strongly correlated with herbage yield there can be major financial benefits from the removal of trees.^[23] The removal of trees also assists grazing management. For example in sheep grazing regions of dense tree and shrub cover harbours predators, leading to increased stock losses^[24] while woody plant cover hinders mustering in both sheep and cattle areas.^[25]

A number of techniques have been employed to clear or kill woody plants in savanna. Early pastoralists used felling and ringbarking, the removal of a ring of bark and sapwood, as a means of clearing land^[26]). In the 1950’s arboricides suitable for stem injection were developed. War-surplus heavy machinery was made available, and these were used for either pushing timber, or for pulling using a chain and ball strung between two machines. These two new methods of timber control, along with the introduction and widespread adoption of several new pasture grasses and legumes promoted a resurgence in tree clearing. The 1980’s also saw the release of soil-applied arboricides, notably tebuthiuron, that could be utilised without cutting and injecting each individual tree.

In many ways ‘artificial’ clearing, particularly pulling, mimics the effects of fire and, in savannas adapted to regeneration after fire as most Queensland savannas are, there is a similar response to that after fire.^[27] Tree clearing in many savanna communities, although causing a dramatic reduction in basal area and canopy cover, often leaves a high percentage of woody plants alive either as seedlings too small to be affected or as plants capable of re-sprouting from lignotubers and broken stumps. A population of woody plants equal to half or more of the original number often remains following pulling of eucalypt communities, even if all the trees over 5 metres are uprooted completely.

Exotic plant species

A number of exotic plants species have been introduced to the savannas around the world. Amongst the woody plant species are serious environmental weeds such as Prickly Acacia (Acacia nilotica), Rubbervine (Cryptostegia grandiflora), Mesquite (Prosopis spp.), Lantana (Lantana camara and L. montevidensis) and Prickly Pear (Opuntia spp.) A range of herbaceous species have also been introduced to these woodlands, either deliberately or accidentally including Rhodes grass and other Chloris species, Buffel grass (Cenchrus ciliaris), Giant rats tail grass (Sporobolus pyramidalis) parthenium (Parthenium hysterophorous) and stylos (Stylosanthes spp.) and other legumes. These introductions have the potential to significantly alter the structure and composition of savannas worldwide, and have already done so in many areas through a numbers of processes including altering the fire regime, increasing grazing pressure, competing with native vegetation and occupying previously vacant ecological niches.^[27][28]

Climate change

There exists the possibility that human induced climate change in the form of the greenhouse effect may result in an alteration of the structure and function of savannas. Some authors^[29] have suggested that savannas and grasslands may become even more susceptible to woody plant encroachment as a result of greenhouse induced climate change. A recent case described involved a savanna increasing its range at the expense of forest in response to climate variation, and potential exists for similar rapid, dramatic shifts in vegetation distribution as a result of global climate change, particularly at ecotones such as savannas so often represent.^[30]

Savanna Ecoregion

· Tropical and subtropical savannas are classified with tropical and subtropical grasslands and shrublands as the tropical and subtropical grasslands, savannas, and shrublands biome. The savannas of Africa, including the Serengeti, famous for its wildlife, are typical of this type.

· Temperate savannas are mid-latitude savannas with wetter summers and drier winters. They are classified with temperate savannas and shrublands as the temperate grasslands, savannas, and shrublands biome.

· Mediterranean savannas are mid-latitude savannas in Mediterranean climate regions, with mild, rainy winters and hot, dry summers, part of the Mediterranean forests, woodlands, and shrub biome. The oak tree savannas of California, part of the California chaparral and woodlands ecoregion, fall into this category.

· Flooded savannas are savannas that are flooded seasonally or year-round. They are classified with flooded savannas as the flooded grasslands and savannas biome, which occurs mostly in the tropics and subtropics.

· Montane savannas are high-altitude savannas, located in a few spots around the world's high mountain regions, part of the montane grasslands and shrublands biome. The highland savannas of the Angolan scarp savanna and woodlands ecoregion are an example.