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EVALUASI LAHAN PERSAWAHAN PADA TIGA DAERAH ALIRAN SUNGAI DI SUMATERA BARAT
Get PDFResearch on soils fertility of rice soils has been done on three catchment in West Sumatra province ie; Ulu Selo ( inland areas of selo river) at Tanah Datar district conducted three Kenagarian ( traditional village) Simpurut, Gurun, and Padang Laweh. Lembang catcment at Solok district is conducted ubo irrigation scheme ubo which divided as Ubo atas irrigation scheme and Sirukam. Sumpur cathment at East Pasaman District conducted three Kenagarian, Lundar, Petok and Kuamang. All of irrigation scheme located at agroclimatic zone C1 up to D2, with charaterize 2 or 3 consecutive wet month and 3 or 4 consecutive dry month. Soils were developed from volcanic parents materials. Rice soils of Ulu Selo shown lower pH value compared to the soils with land use is mixed garden, which some of the sampling point has shown the pH lower than 4. the rice soils of Lembang and Sumpur also shown the similar trend of pH but the value not so extremely like the soils from Ulu Selo. Related to the minimum value of carbon in rice soils is indicate that some of the rice soils in the research areas could be grouping as degraded land. The rice soils from Sumpur has high natural soil fertility which which shown on the natural reserved of nitrogen, phosphor and potassium. The soils condition could support the rice production up to 8t/ha/ GS without additional nutrient. While soils from Ulu Selo shown lower content of phosphor. Based on this research author suggested to fertilizer program is better done based on the condition of soils itself. Even the natural soils fertility is high is not reccomended to use addtional artificials fertilizer.Key words: cathment studies, natural soil fertility, rice production and land degradation.</jats:p
NILAI EKONOMI TIDAK LANGSUNG HUTAN MANGROVE KUALA LANGSA, ACEH (INDIRECT ECONOMIC VALUE OF FOREST MANGROVE KUALA LANGSA, ACEH
Get PDFEkosistem mangrove menyediakan sumber daya dan jasa bagi ekonomi tingkat komunitas, nasional
dalam hal menghasilkan produk, pendapatan, pekerjaan dan perdagangan serta pada tingkat global.
Akan tetapi, nilai ekosistem mangrove hingga kini tidak mudah dikenali, sehingga sering diabaikan
dalam suatu perencanaan pengembangan wilayah pesisir. Ketidaktahuan akan nilai fungsi dan
kurangnya menghargai produk alami dan jasa ekologi ekosistem mangrove adalah kekuatan utama
pendorong konversi sistem mangrove ke penggunaan alternatif. Menilai nilai ekonomi dari barang
dan jasa ekosistem menjadi syarat penting untuk pengambilan keputusan lingkungan. Tujuan
penelitian adalah menghitung nilai ekonomi tidak langsung hutan mangrove Kuala Langsa, Aceh.
Penelitian dilakukakan dengan pengamatan secara purposive sampling dengan metode langsung
dan wawancara. Hasil penelitian menunjukkan nilai total ekonomi tidak langsung sebesar Rp Rp
1.794.150.583,100,-/tahun. Manfaat terbesar berasal dari manfaat tidak langsung Rp
1.082.943.478,700,- atau 74,657%,- manfaat pilihan Rp 141.750.000,000,- atau 7,901 % dan
manfaat keberadaan Rp 225.858.146,400.- atau 12,587%.
Kata Kunci: Nilai Ekononi, Hutan Mangrove, Langsa
Seminar nasional Peragi: Pertanian berkelanjutan mendukung swasembada hasil pertanian dan kesejahteraan petani
Get PDFNILAI EKONOMI TIDAK LANGSUNG HUTAN MANGROVE KUALA LANGSA, ACEH (INDIRECT ECONOMIC VALUE OF FOREST MANGROVE KUALA LANGSA, ACEH
Get PDFEkosistem mangrove menyediakan sumber daya dan jasa bagi ekonomi tingkat komunitas, nasional
dalam hal menghasilkan produk, pendapatan, pekerjaan dan perdagangan serta pada tingkat global.
Akan tetapi, nilai ekosistem mangrove hingga kini tidak mudah dikenali, sehingga sering diabaikan
dalam suatu perencanaan pengembangan wilayah pesisir. Ketidaktahuan akan nilai fungsi dan
kurangnya menghargai produk alami dan jasa ekologi ekosistem mangrove adalah kekuatan utama
pendorong konversi sistem mangrove ke penggunaan alternatif. Menilai nilai ekonomi dari barang
dan jasa ekosistem menjadi syarat penting untuk pengambilan keputusan lingkungan. Tujuan
penelitian adalah menghitung nilai ekonomi tidak langsung hutan mangrove Kuala Langsa, Aceh.
Penelitian dilakukakan dengan pengamatan secara purposive sampling dengan metode langsung
dan wawancara. Hasil penelitian menunjukkan nilai total ekonomi tidak langsung sebesar Rp Rp
1.794.150.583,100,-/tahun. Manfaat terbesar berasal dari manfaat tidak langsung Rp
1.082.943.478,700,- atau 74,657%,- manfaat pilihan Rp 141.750.000,000,- atau 7,901 % dan
manfaat keberadaan Rp 225.858.146,400.- atau 12,587%.
Kata Kunci: Nilai Ekononi, Hutan Mangrove, Langsa
Analisis Keberlanjutan Sumber Daya Air di Das Batang Kuranji, Padang dengan Nedbør Afstrømnings Model (NAM)
Get PDFAbstrak. Daerah aliran sungai (DAS) Batang Kuranji merupakan kawasan yang berperan penting dalam kelestarian
sumber daya air dan konservasi di Kota Padang. Meski demikian, dewasa ini keberlanjutan sumber daya air tersebut
telah mengalami kerusakan yang secara hidrologis ditandai dengan debit banjir yang berfluktuasi tajam. Penelitian
ini bertujuan untuk mengukur keberlanjutan sumber daya air di DAS Batang Kuranji. Metode yang digunakan pada
penelitian ini adalah pemodelan Nedbør Afstrømnings Model (NAM) dan pendekatan terintegrasi. Hasil pemodelan
NAM meperlihatkan nilai parameter yang paling menonjol adalh TIF (0,9), TG (0,965), CK1 (0,23), dan CK2 (1,1)
yang mengindikasikan adanya perubahan pada infiltrasi di DAS Batang Kuranji. Analisis terintegrasi
memperlihatkan deforestai dan pertumbuhan penduduk adalah faktor utama permasalahan di DAS tersebut. Hal ini
dipengaruhi oleh alih fungsi lahan di wilayah tersebut. Menekan laju pertumbuhan penduduk, mengevaluasi arah
perkembangan kota, penghijauan, serta memperbaiki infrastruktur bangunan air di sepanjang sungai akan
mengurangi resiko kerusakan DAS serta mempertahankan keberlanjutannya.
Kata Kunci - daerah aliran sungai; Batang Kuranji; keberlanjutan sumber daya air; Nedbør Afstrømnings Model
LAND USE PLANNING AND LAND EVALUATION OF THE UPPER CATCHMENT AREA OF BATANG HARI RIVER
Get PDFThe upper catchment of Batang Hari river in this report is define for the areas of Batang Hari at the end point of Batang Hari Irrigation scheme project at the village of Teluk Kayu Putih of district of Tebo of the Jambi Province up to the Twin lake Of Danau Diateh in the inland areas of Batang Hari river. Covered the areas about 695.400ha which divide to the sixth of sub catchment ie; Momong (41.750ha); Bt. Hari (184.340ha); Sangir (128.660ha); Siat about 45.100ha with divided into small catchment of the Siat river tributaries which main Siat tributary (32.800ha), Piruko/Palangko tributary (7.300ha), Mimpi tributary (5.000ha); Jujuhan (187.300ha) and Pangian (108.250ha). Detail of information showed at Fig. 1 and table 1. Except of sub catchment of Momong, Jujuhan and Pangian, three tributaries already used for irrigation water. The new construction of dam for irrigation scheme are located after joint tributaries of Sangir which flow from Lake Rawa Banto of Mount Krinci and Batang Hari tributary which flow from Lake DiAteh. The length of each main stream Sangir and batang Hari is 118 km and the total length of tributaries conducted of both tributaries is 603km.
Based on the hydrological point of view Sangir tributaries is important because these areas high in the annual rainfall. The amount of precipitation of station Liki, Pinang Awan and lubuak Gadang has recorded more than 4000mm annually. The areas could be grouped to the Zone Agroclimatic A of Oldelman. Batang Hari tributaries which average annual precipitation less than 2500mm, these amount is average value of station Alahan Panjang, Surian, and Muaro labuh which each station are differ in the agroclimatic zone, Zone agroclimate C2, D1, and B1 for Alahan Panjang, Surian and Muaro Labuh respectively. The old river terrace of Batang Hari which developed for irrigation scheme has covered the areas on 20000ha conducted areas along the old river terrace of Batang Hari which parts of Siat, Piruko/Palangko, and Mimpi up to the old terrace at cross of the tributary of Jujuhan which main stream. Different elevation between old river terrace with inland areas both Rawa Banto of Sangir and Lake Diateh of Batang Hari is 1300m.
Hydrological data of river water discharge by used the value 90% of run off data, which calculate base on the average annual rainfall multiplication by the wide of catchment. These value are not significant different which average 18 years data from 1975-1993 of Automatic Water Level Recording (AWLR). In the value 277m3/det and 284m3/det for average value of AWLR and 90% of runoff value respectively. Compare to the AWLR record in 1975 water discharge is decrease. The data of 1975 is 61% compare to runoff data or 60% compare to average data of AWLR. These indicated that the type of land use of the upper cathment already changed. The amount of discharge has decreases in the value of 40% from the average value as the effect of deforestation during the last 30 years. The hydrological condition also observed at the Siat river. The rate of deforestation could be calculated by using the value of forest contribution to the regional annual budget (PDRB). The validity of the method has needed honesty of the timber company. If the company or government official not fair, for calculation should be used correction factor 50-100 percent. Base on the PDRB data rate of deforestation has calculated in the value of 5000-7000ha/yr. related to the calculation the catchment of Siat, Mimpi, Piruko/Palangko already degraded and Siat river in the dry season especially in August conot open the water intake for irrigation as lack of water discharge.
Key words: Rain fall, water discharge, deforestation, and sustainable watershed managemen
PELAPUKAN DAN PEMBENTUKAN TANAH DI DAERAH ALIRAN SUNGAI PADA BERBAGAI TIPE BAHAN INDUK DAN IKLIM
Get PDFBuku dengan judul Pelapukan dan Pembentukan tanah di daerah aliran Sungai pada berbagai batuan induk dan iklim adalah alih bahasa dari desertasi saya yang berjudul The Method For Measuring Rates of Weathering and Soil Formation in Watersheds yang kemudian dilengkapi dengan data dari batuan yang berumur tua dari Hubbard Brook. Basis peneletian berada di daerah Temperate Daerah aliran sungai Iu di Matsue barat Daya Jepang, disini monitoring terhadap faktor lingkungan dilakukan selama 3 tahun, basis kedua adalah daerah hutan hujan tropis di Gunung Gadut Sumatra Barat, yang monitoring dilakukan selama 2 tahun. Sungai Iu memiliki batuan induk Granit, Andesit dan Basic piroklastik material, sedangkan Gunung Gadut memiliki batuan induk Andesit dengan umur tertier awal. Daerah ketiga adalah Hutan peneletian Ekologi Hutan di New Hampshire yaitu station Hubbard Brook, stasiun ini memiliki data pengamatan lingkungan lebih dari 100 tahun, untuk melengkapi tentang data batuan dan tanah dilakukan survery pada tahun 2003.
Ketiga daerah berbeda baik dari segi iklim maupun batuan induk, Hubbard Brook adalah yang paling ekstrim karena memiliki batuan glacial till berumur Devon dan Silur dengan iklim kutub, sedangkan Gunung Gadut berumur tertier awal dengan iklim hutan hujan tropis, Daerah aliran sungai Iu berumur Miocene
Buku itu dimulai dari pertanyaan dasar, Berapa lama waktu yang dibutuhkan untuk membentuk 10 cm tanah. Hal ini diperlukan untuk menghitung berapa lama umur tanah akan bertahan bila erosi tanah akan mengikis tanah sedalam 2cm pertahun.
Mudah mudahan buku ini dapat membantu ahli lingkungan tentang bahaya erosi dan sedimentasi dan usaha dari masyarakat untuk menjaga agar tanah tidak hanyut dalam jumlah yang melebihi dari kecepatan pembentukannya
Sertifikat seminar 14th IICGDTR Tema: Governance challenges of green development in tropical soils
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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