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Abstrak :
This research was conducted by the problem of population differences bintangur in Sei Tembesi and Bukit Tiban Protected Forest allegedly influenced by macro nutrient content in the soil. The study was conducted using a survey method. Samples were taken by purposive by following along a 100 m transect lines that divide the contour lines. Transect were initiated at least 50 m from the edge of the forest that are placed propossionally and prioritized on location around bintangur population. Soil sampling conducted on the soil surface of ± 5 cm to a depth of ± 25 cm from the soil surface. Based on the research that there are differences in soil organic matter content in the protected forest and macro nutrient in the soil. Soil pH is at the same relativity value, but that value is an extreme value when compared with the value according to criteria of Soil Chemical Properties. This soil conditions is able to inhibit the growth of bintangur. Bintangur population in both of the protected forest can be maintained through soil conservation biological.

Penelitian ini dilatarbelakangi oleh permasalahan perbedaan populasi bintangur di Hutan Lindung Sei Tembesi dan Bukit Tiban yang diduga dipengaruhi oleh kandungan hara makro di dalam tanah. Penelitian dilakukan menggunakan metode survei. Sampel diambil dengan cara purposive dengan mengikuti jalur transek sepanjang 100 m yang membelah garis kontur. Jalur transek tersebut dimulai minimal 50 m dari tepi hutan yang ditempatkan secara proporsional dan diprioritaskan pada lokasi sekitar populasi bintangur. Pengambilan sampel tanah dilakukan pada permukaan tanah ± 5 cm pada kedalaman ± 25 cm dari permukaan tanah. Berdasarkan hasil penelitian diperoleh informasi bahwa terdapat perbedaan kandungan bahan organik tanah di kedua hutan lindung tersebut dan kandungan hara makro di dalam tanah. pH tanah berada pada nilai yang relatif sama, namun nilai tersebut merupakan nilai yang ekstrim bila dibandingkan dengan Kriteria Penilaian Sifat Kimia Tanah. Kondisi tanah seperti itu mampu menghambat pertumbuhan bintangur. Populasi bintangur di kedua hutan lindung tersebut dapat dipertahankan melalui konservasi tanah secara biologi.

Abstrak :
Penelitian ini bertujuan untuk mengetahui pengaruh distribusi curah hujan dan karakteristik fisik setiap sub-DAS Ci Liwung Hulu yang terdiri dari topografi, jenis tanah dan penggunaan tanah terhadap debit aliran Daerah Aliran Ci Liwung Hulu. Metode yang digunakan adalah Soil Conservation Service (SCS) yang disimulasikan menggunakan model hujan-debit HEC-HMS yang di validasi menggunakan metode RMSE dan Nash. Hasil pengolahan data menunjukan bahwa karakteristik dan distribusi hujan setiap sub-DAS mempengaruhi besar kecilnya debit yang dihasilkan. Sub-DAS Ci Liwung (Tugu) merupakan sub-DAS yang menghasilkan sumbangan debit terbesar pada DA Ci Liwung Hulu pada kejadian banjir Tahun 2002 dan 2007. Berdasarkan hasil validasi, simulasi, data curah hujan radar cuaca memiliki nilai simpangan yang lebih kecil dibandingkan data curah hujan observasi. Penggunaan data radar cuaca memberikan gambaran distribusi hujan spasial dengan resolusi tinggi dan dapat digunakan untuk memprediksi debit aliran yang dihasilkan oleh suatu Daerah Aliran Sungai (DAS).

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This study aims to determine impact of rainfall distribution and physical characteristics in each sub-watershed towards run-off in the Upper Ci Liwung Watershed. It consist of topography , soil type and land use. The method utilizing Soil Conservation Service (SCS ) applied on HEC - HMS rainfallrunoff model and was validated using the RMSE and Nash. The results show that the physical characteristics and rainfall distribution of each sub-watershed has significant impact on the run-off in Upper Ci Liwung Watershed especially sub-watershed Ci Liwung ( Tugu) on the flood events of 2002 and 2007. Based on the simulation validation result, weather radar rainfall data has a deviation value smaller than rainfall data of observation . Weather radar data provide accurate rainfall measurements at high resolution and can be applied to predict run-off in watershed.

Abstrak :
DAS Cisadane termasuk dalam DAS prioritas dengan status untuk dipulihkan. Perkembangan penduduk dan perubahan penggunaan tanah di daerah tersebut menjadi salah satu permasalahan terhadap kebutuhan akan sumber daya air akibat berkurangnya wilayah resapan air, sehingga identifikasi wilayah resapan diperlukan untuk menjaga dan memperbaiki fungsi resapan air. Pemetaan potensi resapan air dilakukan dengan model RTkHL-DAS dan SCS-CN menggunakan data jenis tanah, curah hujan, lereng dan penutup lahan yang diperoleh dari peta analog dan data penginderaan jauh (CHIRPS, Landsat 8 dan DEMNAS). Model dari RTkHL-DAS dilakukan modifikasi untuk membuat model terbaru yaitu model I dengan perubahan data penutup lahan menjadi NDVI dan Model II dengan mengubah jenis tanah menjadi SMI dan penambahan kriteria densitas drainase pada model I, serta dilakukan pembobotan hasil normalisasi bobot penelitian terdahulu. Kedua model diproses dengan metode multi-kriteria dengan teknik weight overlay untuk menghasilkan kelas potensi resapan air. Hasil menunjukkan resapan air model Model RTkHL-DAS dengan menggunakan menghasilkan kelas baik (65,6%), Normal Alami (4,6%), mulai kritis (5,7%), agak kritis (22,1%) dan kritis (2%). Model SCS-CN dengan nilai CN dari 20-40 (23%), 60-80 (52,10%) dan 80-100 (24,90%). Berdasarkan hubungannya dengan fluktuasi muka air tanah, kedua model memiliki hubungan dengan perubahan fluktuasi muka air tanah dengan masing-masing kelas yang dihasilkan dari tiap model. Model I menghasilkan 4 kelas potensi resapan air yaitu sangat tinggi (1,9%), tinggi (40,8%), sedang (55,8%), dan rendah (1,5%), memiliki keunggulan dalam mendeteksi variasi kelas pada kondisi dominan hutan/vegetasi. Sedangkan Model II menghasilkan kelas sangat tinggi (0,3%), tinggi (53,4%), sedang (44,6%), dan rendah (1,7%). Memiliki keunggulan dalam mendeteksi variasi kelas pada kondisi dominan permukiman/sawah yang diperkuat dengan hubungan fluktuasi muka air tanah di wilayah tengah-hilir terhadap luas kelas potensi resapan air di mana Model II mengungguli Model I. ......The Cisadane watershed is included in the priority watershed with status for restoration. Population development and changes in land use in the area are one of the problems with the need for water resources due to reduced water catchment areas, so the identification of recharge areas is needed to maintain and improve the function of water catchments. The mapping of recharge potential was carried out using the RTkHL-DAS and SCS-CN models using data on soil types, rainfall, slopes, and land cover obtained from analog maps and remote sensing data (CHIRPS, Landsat 8, and DEMNAS). The model from the RTkHL-DAS was modified to create the latest model, namely model I by changing the land cover data to NDVI and Model II by changing the soil type to SMI and adding drainage density criteria from model I, as well as weighting the results of the normalization of the weights of previous studies. Both models were processed using a multi-criteria method with a weight overlay technique to produce a class of water infiltration potential. The results show that the water infiltration of the RTkHL-DAS model using the good class (65.6%), Natural Normal (4.6%), critical (5.7%), moderately critical (22.1%), and critical ( 2%). SCS-CN model with CN values from 20-40 (23%), 60-80 (52.10%) and 80-100 (24.90%). Based on its relationship with groundwater level fluctuations, both models have a relationship with changes in groundwater level fluctuations with each class resulting from each model. Model I produces 4 classes of water infiltration potential, namely very high (1.9%), high (40.8%), moderate (55.8%), and low (1.5%). Effective in detecting classes in dominant conditions of forest/plantation. While Model II produces very high (0.3%), high (53.4%), medium (44.6%), and low (1.7%). It has the advantage of detecting class variations in the dominant conditions of settlements/rice fields which is strengthened by the relationship between groundwater level fluctuations in the middle-downstream region to the class area of water infiltration potential where Model II outperforms Model I.

Abstrak :
This book summarizes a long-term research project addressing land and water use in the irrigated areas of the Aral Sea basin. In an interdisciplinary approach, natural and human sciences are combined to elucidate the challenges of economic transition that affect the use of land, water and biological resources, ecological sustainability, economic efficiency and the livelihoods of the local population. The research focuses on Khorezm, a region in Uzbekistan, located on the Amudarya river, in the heart of Central Asia. A series of chapters describes the biophysical environment and the aspects of society and institutions that shape land and water use. The book discusses options and tools to improve land and water management, and to reform the economic system management, based on agronomic, hydrological, economic ans social studies and modeling. The insights are not only important for Uzbekistan, but for all countries in transitions and irrigated dryland areas elsewhere.