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Changes in the characteristics of after logging streamflow hydrograph of Eucalyptus pellita F. Muell stands Supangat, Agung Budi
Jurnal Penelitian Kehutanan Wallacea Vol 6, No 1 (2017): Jurnal Penelitian Kehutanan Wallacea
Publisher : Environment and Forestry Research and Development Institute of Makassar

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1173.074 KB) | DOI: 10.18330/jwallacea.2017.vol6iss1pp1-11

Abstract

The wide scale development of Eucalyptus pellita F. Muell plantation in Riau Province applying the clear cutting silvicultural system on fast-growing tree species allegedly have an impact on the changing of watershed hydrological functions. The aim of this study was to determine the changes in the characteristics of after logging stream flow hydrograph of E. pellita forest stand. The research was carried out in E. pellita plantations in Perawang, Riau Province using 4.62 ha of micro-catchment as an observation unit. The method used is the analysis of hydrograph units on chosen data of flood hydrograph. The research concludes that clear-cutting system has led to increasing the peak flow discharge from an average of 0.226 m3.s-1 to be 0.322 m3.s-1, shortening the time base of hydrograph from an average of 143 minutes to be 90 minutes, shortening the time to peak flow from an average of 80 minutes to be 40 minutes, as well as declining the base flow from an average of 0.0056 m3.s-1 to be 0.0032 m3.s-1.
ANALISIS SPASIAL KEMAMPUAN LAHAN DALAM PERENCANAAN PENGELOLAAN DAS MIKRO Wahyuningrum, Nining; Supangat, Agung Budi
MAJALAH ILMIAH GLOBE Vol 18, No 1 (2016)
Publisher : Badan Informasi Geospasial

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1131.601 KB) | DOI: 10.24895/MIG.2016.18-1.393

Abstract

Untuk mewujudkan kondisi lahan yang produktif sesuai dengan daya dukung DAS diperlukan rencana detil sehingga mudah diterapkan di lapangan. Perencanaan detil perlu didahului dengan penelaahan global untuk mengetahui gambaran umum kondisi lahan aktual, sehingga dapat digunakan untuk menetapkan prioritas-prioritas lokasi yang penting untuk segera ditangani. Dalam paper ini dilakukan analisis kemampuan penggunaan lahan (land use capability analysis) skala detil (DAS mikro) berdasar kepada informasi semi detil (sub DAS) dengan menggunakan ArcMap 9.3. Penelitian dilakukan di DAS Mikro Naruwan yang termasuk dalam Sub DAS Keduang, DAS Solo. DAS Solo merupakan salah satu dari 108 DAS prioritas yang harus dipulihkan. Hasil analisis menunjukkan bahwa 38% lokasi penelitian didominasi tegal, kebun campur 23%, hutan 20% dan sisanya oleh sawah, permukiman dan semak belukar. Meskipun kebun campur dan hutan mendominasi, akan tetapi terdapat 56,24% penggunaan lahan yang tidak sesuai dengan klas kemampuan lahannya. Pada lahan yang tidak sesuai tersebut 33,14% mengalami erosi pada taraf sangat berat (>480 ton/ha). Lahan yang tidak sesuai tersebut terutama adalah tegal. Karena sebagian besar merupakan lahan milik masyarakat sehingga tidak mudah untuk merubah penggunaannya. Oleh sebab itu perlu dilakukan kompromi untuk mengurangi dampak negatifnya yaitu dengan pengembangan hutan rakyat dengan sistem agroforestri, perbaikan hutan di bantaran sungai, peningkatan persentase penutupan lahan, pembuatan teras gulud, pemberian mulsa, pembuatan rorak, pembangunan dam penahan dan dam pengendali untuk mengendalikan erosi. Kata kunci: kemampuan lahan, penggunaan lahan, erosi, perencanaan, konservasiABSTRACTTo create a productive land condition in accordance with the carrying capacity of watershed needs a detailed planning so it is applicable in the field. The detailed planning needs to be preceded by a global assessment to comprehend the actual general description, so it can be used to set priorities that are important to be addressed. In this paper, land use capability analysis were used in the detail planning (micro-catchment) based on the semi-detail (sub-watershed) information by utilizing GIS analysis. The study was conducted in Naruwan micro watershed which is included in Keduang Sub-Watershed of Solo Watershed. Solo Watershed is one of 108 watersheds that should be recovered. Analysis show that 38% of the area is dominated by dryland, 23% mixed garden, 20% production forest, and the rest consisted of paddy field, settlement and shrubs. Although the mixed garden and forest dominate, but there are 56,24% of the land use that is suitable to its land capability. The 33,4% of the unsuitable land use, have very severe erosion (>480 ton/ha). The unsuitable land use is  dry land agriculture. Since most of the land belonging to the community, so it is not easy to change its usage. Therefore it is necessary to compromise the type of land uses which reducing its negative impact namely the development of community forest by applying  agroforestry system, improvement of riparian forest, increasing the percentage of permanent land cover, terracing, mulching, manufacture of sediment trap (rorak), building retaining dam and control dam to control erosion.Keywords: land capability, land use, erosion, planning, conservation
PENGARUH PENEBANGAN HUTAH TANAMAN EUCALYPTUS PELLITA F.Muell DALAM PENINGKATAN ALIRAN SUNGAI DAN SEDIMEN Supangat, Agung Budi; Sudira, Putu; Supriyo, Haryono; Poedjirahajoe, Erny
Jurnal Penelitian Hutan Tanaman Vol 13, No 2 (2016): JURNAL PENELITIAN HUTAN TANAMAN
Publisher : Pusat Penelitian dan Pengembangan Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2131.155 KB) | DOI: 10.20886/jpht.2016.13.2.113-122

Abstract

ABSTRACTThe study aimed to determine the effect of harvesting on the river flow and sedimentation. The research was carried out in Eucaliptus pellita plantations forest in Perawang District, Riau Province. The catchment water balance method was used by using the micro-catchment as observation unit. The research concluded that clear cutting system led triver flow increment by 142.6% in the period 0 to 8 months after harvesting, from 45.5 mm.month-1(before logging) to 110.5 mm.month-1(after logging). Monthly runoff coefficient increased by 95.3% from 34.0% to 66.0%. I Clear-cutting also increased monthly sediment yield by 788.7% from 0.18 ton.ha-1.month-1(before logging) to 1.57 ton.ha-1month-1(after logging).Keywords: Clear cutting, E. pellita, plantation forest, river flow and sedimentABSTRAKTujuan penelitian ini adalah untuk mengetahui pengaruh penebangan hutan tanaman terhadap aliran sungai dan sedimentasi. Penelitian dilaksanakan di kawasan hutan tanaman E. pellita di Perawang, Propinsi Riau.Teknik yang digunakan adalah metode pengukuran neraca air dengan menggunakan satuan pengamatan berupa mikro DAS. Hasil penelitian menunjukkan bahwa akibat penebangan dengan sistem tebang habis telah menyebabkan peningkatan aliran sungai sebesar 142,6% pada periode 0 sampai 8 bulan setelah penebangan dari rata-rata 45,5 mm per bulan (sebelum penebangan) menjadi 110,5 mm per bulan (setelah penebangan) serta meningkatkan koefisien limpasan permukaan bulanan sebesar 95,3%, yakni dari 34,0% menjadi 66,0%. Kegiatan penebangan menyebabkan peningkatan sedimen bulanan sebesar 788,7% dari 0,18 ton per ha per bulan sebelum penebangan menjadi 1,57 ton per ha per bulan setelah penebangan.Kata kunci: E. pellita, debit, hutan tanaman, sedimen dan tebang habis
Studi Intersepsi Hujan pada Hutan Tanaman Eucalyptus Pellita di Riau Supangat, Agung Budi; Sudira, Putu; Supriyo, Haryono; Poedjirahajoe, Erny
Agritech Vol 32, No 3 (2012)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (355.741 KB) | DOI: 10.22146/agritech.9610

Abstract

The aim of this study is to know the magnitude of rainfall interception loss in E. pellita plantation forest, at PerawangRiau. In order to obtain the magnitude of interception loss, stemfl ow and throughfall were measured on E. pellita plants at ages of 2 to 6 years with replication of 3 times, respectively. The results showed that the magnitudes of interception loss, throughfall and stemfl ow were 13.3-18.7 %; 7.7-83.1 % and 3.6-4.1 % from rainfall, respectively. The canopy storage capacity was calculated at 0.8 mm. The relationships of rainfall against both throughfall and stemfl ow showed strong correlations with r2 values of 0.99 and 0.79, respectively; while rainfall against interception has moderate correlation with r2 value of 0.58.ABSTRAKPenelitian ini bertujuan untuk mengetahui besarnya kehilangan air melalui intersepsi di hutan tanaman E. pellita, di Perawang-Riau. Untuk menghitung besarnya nilai intersepsi, dilakukan pengukuran aliran batang (stemfl ow) dan lolosan tajuk (throughfall) pada umur tanaman 2, 3, 4, 5, dan 6 tahun, masing-masing 3 ulangan pohon. Hasil penelitian menunjukkan besaran kisaran nilai intersepsi, throughfall dan stemfl ow masing-masing 13,3-18,7 %; 7,7-83,1 % dan 3,6-4,1 % dari curah hujan. Kapasitas tampungan tajuk (canopy storage capacity) tanaman E. pellita rata-rata sebesar 0,8 mm. Hubungan curah hujan dengan throughfall dan stemfl ow menunjukkan korelasi yang kuat (r2 rata-rata 0,99 dan 0,79), sedangkan dengan intersepsi korelasinya kurang kuat (r2 rata-rata 0,58).
SIMULASI MODEL DINAMIK PENGARUH LEGUME COVER CROPS (LCC) TERHADAP LIMPASAN DAN SEDIMEN DI LAHAN HUTAN TANAMAN (Dynamic model simulation of the effects of Legume Cover Crops (LCC) on runoff and sediment in plantation forest land) Supangat, Agung Budi; Sudira, Putu; Supriyo, Haryono; Poedjirahajoe, Erny
Jurnal Penelitian Pengelolaan Daerah Aliran Sungai Vol 2, No 1 (2018): Jurnal Penelitian Pengelolaan Daerah Aliran Sungai
Publisher : Balai Penelitian dan Pengembangan Teknologi Pengelolaan DAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1159.109 KB) | DOI: 10.20886/jppdas.2018.2.1.17-34

Abstract

Declining productivity of plantation forest due to low soil fertility. This condition has forced  managers to make efforts in manipulating the tree growing environment. One such effort is by introducing cover crops species from legumes (LCC), to control surface runoff, soil erosion and input nutrient into the soil. The research aims to determine the effectiveness of LCC in controlling total runoff and sedimentation in Eucalyptus pellita plantations, through dynamic model simulation. The dynamic model of STELLA version 9.0.2 was used to study water and nutrient cycles, focused on the application of LCC to reduce total runoff and sedimentation. The results showed that LCC could drop the total runoff of average 35% in the 1 - 2 years old. In the 1styear it decreased from 1,530 mm to 994 mm, while in the 2ndyear it decreased from 1,240 mm to 806 mm. The declining also occurred in the sediment content, in the 1st year it decreased from 12.20 tonnes/ha to 7.93 tonnes/ha, and the 2nd year it decreased from 6.63 tonnes/ha to 4.36 tonnes/ha. These research findings can be used by the environmental manager  to minimize potential land degradation, especially during the post-harvest until the young plantations (0-2 years old) phases.
PENGARUH PERSENTASE PENUTUPAN HUTAN TERHADAP DEBIT PUNCAK DI SUB DAERAH ALIRAN SUNGAI HUTAN ALAM KABUPATEN TANAH LAUT (The effect of forest coverage percentage on peak discharge in the natural forest sub watershed, Tanah Laut Regency) Nugrahanto, Esa Bagus; Adi, Rahardyan Nugroho; Supangat, Agung Budi; Nugroho, Nunung Puji
Jurnal Penelitian Pengelolaan Daerah Aliran Sungai Vol 2, No 2 (2018): Jurnal Penelitian Pengelolaan Daerah Aliran Sungai
Publisher : Balai Penelitian dan Pengembangan Teknologi Pengelolaan DAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (591.286 KB) | DOI: 10.20886/jppdas.2018.2.2.123-136

Abstract

The percentage of forest coverage holds an important role in regulating water in watersheds. This paper studies the influence of forest coverage percentage on peak discharge in sub watersheds with various percentage of natural forest areas. The study took place in Bakar, Tanjung, Iwakan, and Langsat Sub Watersheds, Tanah Laut Regency, South Kalimantan Province in 2017. The percentage of natural forest varied from 9,7 to 98% of the the sub watershed areas. This research was conducted by direct measurement of rainfall and stream water levels that were converted into peak discharge. The peak discharges between sub watersheds were compared to the rainfall and the percentage of forest. The results showed that in general the percentage of natural forest coverage affect the peak discharge. The forest coverage showed a positive response in lowering the peak discharge when the rainfall was below 115 mm/day. Bakar and Tanjung Sub Watersheds that had low percentage of natural forest coverage had higher peak discharge than Langsat and Iwakan Sub Watersheds, which had higher percentage of forest coverage. The relationship between the percentages of natural forest coverage with peak discharge marked by the coefficient of   determination value of 53.3%. Since the existence of forest is very important as the hydrological controller, forest conservation efforts and reforestation should be conducted in the upper sub watersheds.