Predicting Soil Erosion Using the Soil and Water Assessment Tool (SWAT) Model in Giritengah Catchment Area

Giritengah catchment is 5 km to the southwest of Borobudur Temple and is an area that has been designated as a buffer zone which acts as a support zone for tourism activities in the Borobudur Area. The purpose of this study is to predict erosion in the Giritengah catchment and develop a scenario for the application of the right Soil and Water Conservation (SWC) techniques to reduce erosion in the Giritengah catchment. Erosion estimation is carried out using the Soil and Water Assessment Tool (SWAT) model. The results showed  that the average amount of erosion is 30.7 tons/ha/year with the highest average erosion being on dry land use. The classification of the predominant Erosion Hazard Level is in the very low, low and heavy classes. The application of the right SWC technique in the form of bench and ridge terraces structure is expected to be able to reduce erosion that occurs in the Giritengah catchment to very low Erosion Hazard Level (EHL) classes reaching 60.4% of the total area and eliminate heavy EHL classes

Hubungan Anasir Hujan Dengan Erosi Pada Hutan Jati Yang Dimodifikasi (\u27Management Regime IV") Dan Hutan Jati Konvensional Di BKPH Dungus, KPH Madiun

Studies on the relationship between rainfall and erosion have been conducted at many sites or locations. However, only a lbw studies on the relationship between rainfall and erosion in teak forest, especially which are managed by both Management Regime (MR) and conventional, have been reported. The first objective of this study was to measure and analyze the erosion in the teak forests managed by Management Regime IV (MR IV) and conventional, and analyze the relationship between rainfall and the erosion. The second objective was to compare the erosion rates between the teak forests managed by Management Regime IV (MR IV) and conventional. Two erosion plots of4 x 22 m were positioned in the teak forests, one plot was placed in the teak Ibrest managed by MR IV and another plot was placed in the teak forest managed by conventional method. Twenty four rainfall data were recorded in the same time, the erosion in the plots were measured and analyzed. The multiple regression used to analyze the data. The results of the research showed that the erosion rates between the teak Ibrests managed by Management Regime IV (MR IV) and conventional method were not significantly di flbrent. The results oldie research also showed that the relationship between rainfall (depth and duration) and erosion rates at the teak forests both in MR IV and conventional methods were significantwhile the relationship between rainfall intensities and the erosion rates at the teak forest either in MR IV or conventional method were not significant. Keywords : erosi, hutan jati, MR IV PENDAHULUA

Intensifikasi Lahan Tegalan Untuk Meningkatkan Penghasilan Warga Masyarakat Model Daerah Aliran Sungai (DAS) Mikro Cangkringan

Kerusakan lingkungan di Indonesia semakin meningkat sebagai akibat terjadinya bencana banjir, tanah longsor dan kekeringan yang semakin meningkat. Berbagai upaya perbaikan kondisi DAS sudah dilakukan untuk mewujudkan keseimbangan lingkungan dan tata air DAS serta memberikan manfaat sosial ekonomi yang nyata bagi masyarakat. Kegiatan pengabdian ini bertujuan untuk meningkatkan pengetahuan, pemahaman dan kesadaran masyarakat terhadap kondisi lingkungan dan upaya pelestariannya; meningkatkan produktivitas lahan melalui pola agroforestri; dan meningkatkan pendapatan masyarakat MDM Cangkringan. Metode yang digunakan adalah melalui pembangunan demplot partisipatif. Dalam hal ini masyarakat terlibat secara aktif sejak dari perencanaan sampai dengan pelaksanaan pembangunan demplot intensifikasi pada lahan tegalan oleh kelompok tani Maju Makmur. Hasil pengabdian dapat disimpulkan bahwa melalui sosialisasi kegiatan maka diperoleh adanya peningkatan pengetahuan, pemahaman dan kesadaran masyarakat terhadap kondisi lingkungan dan upaya pelestariannya. Dalam perencanaan partisipatif, diperoleh bahwa jenis yang dipilih adalah sengon karena memberikan keuntungan ganda yaitu aspek ekologi dan ekonomi. Peningkatan produktivitas lahan pekarangan dilakukan dengan metode yang ramah lingkungan dalam bentuk intensifikasi pekarangan melalui pola agroforestri. Pengembangan agroforestri dilakukan dengan membuat plot percontohan (demplot) oleh kelompok tani Maju Makmur. Selanjutnya, pengembangan agroforestri dapat memberikan hasil berupa berbagai jenis tanaman yang dibudidayakan oleh petani dan dapat dipanen secara berkelanjutan

Potensi Jasa Lingkungan Penyerap Karbon dan Penyedia Oksigen Hutan Lindung Mangunan, Yogyakarta

Forests have multifunction ecology, one of which is environmental services as a CO2 absorber and and O2 producer. The fact is that until now the magnitude of the potential for environmental services as carbon sinks and oxygen producers in the Mangunan Protection Forest is not known, so it is important to research it. The focus of this research is to determine the potential for environmental services in the form of biomass potential, carbon potential, carbon sinks, oxygen providers and their economic value. Carbon data collection in the field by measuring DBH and height of woody vegetation. Calculations using the 2011 BSNI standard and analyzed descriptively. The biomass potential of the Mangunan Protected Forest is 52.83 tons/ha and has threats in the form of trees and fires, so it needs to be preserved. Mangunan Protected Forest Environmental Services in the form of CO2 absorbers of 193.87 tons/ha/year and O2 producers of 141.53 tons/ha/year. The environmental services, if translated properly, are worth Rp. 2,122,640,368. Keywords: environment, sustainability, climate, biomass, vegetation  ABSTRAK Hutan memiliki multifungsi ekologi, salah satunya adalah jasa lingkungan sebagai penyerap CO2 dan penghasil O2. Faktanya sampai saat ini belum diketahui besarnya potensi jasa lingkungan sebagai penyerap karbon dan penghasil oksigen di Hutan Lindung Mangunan, sehingga penting untuk diteliti. Fokus penelitian ini adalah untuk mengetahui potensi jasa lingkungan berupa potensi biomassa, potensi karbon, penyerap karbon, penyedia oksigen dan nilai ekonominya. Pengumpulan data karbon di lapangan dengan mengukur DBH dan tinggi vegetasi berkayu. Perhitungan menggunakan standar BSNI 2011 dan dianalisis secara deskriptif. Potensi biomassa Hutan Lindung Mangunan sebesar 52,83 ton/ha dan memiliki ancaman berupa pohon dan kebakaran sehingga perlu dilestarikan. Jasa Lingkungan Hutan Lindung Mangunan berupa penyerap CO2 sebesar 193,87 ton/ha/tahun dan penghasil O2 sebesar 141,53 ton/ha/tahun. Jasa lingkungan tersebut, jika diterjemahkan dengan baik, bernilai Rp. 2.122.640.368. Kata kunci: lingkungan, kelestarian, iklim, biomassa, vegetasi     

Social and Economic Vulnerability in The Sub-Watershed of Karang Mumus, East Kalimantan Province

Changes in land use influence the social and economic characteristics as well as the environmental problems in a sub-watershed. To support the management of a sub-watershed, land use scenarios (biophysics) must be prepared and community involvement level must be improved. So far, the factors used for monitoring and evaluating sub-watershed performance have not been used thoroughly. This research is aimed at finding out the social and economic vulnerabilities tied to the monitoring and evaluation of sub-watershed performance across the sub-districts. This research uses quantitative methods employed to process primary data (biotic: vegetation and settlement, and abiotic: land, climate, geomorphology, and geology), secondary data (community data sourced from the data of BPS; Central Bureau of Statistics) of East Kalimantan Province; in September 2017), and socio-economic data (direct interviews using questionnaires). The primary data were obtained after processing map interpretation and from observation. The results show that high socio-economic vulnerability occurs in areas of high land use vulnerability. Sub-watershed management will be successful if it is done through a "collaborative management" involving all stakeholders. The scenario simulations of this research can be used as reference materials for regional governments in planning, compiling, and implementing the Regional Spatial Plan policies

TINGKAT EROSI DAN RANCANGAN TEKNIK KONSERVASI TANAH DAN AIR DI SUB DAS WAEWOKI, DAS AESESA KABUPATEN NGADA PROVINSI NUSA TENGGARA TIMUR (Erosion Level and Soil and Water Conservation Engineering Plan in Waewoki Sub Watershed, Aesesa Watershed, Ngada Regency, East Nusa Tenggara Province)

AbstrakKajian tingkat erosi dan rancangan Konservasi Tanah-Air (KTA) telah dilakukan di Sub DAS Waewoki DAS Aesesa Kabupaten Ngada Provinsi Nusa Tenggara Timur. Penelitian ini bertujuan untuk memprediksi tingkat erosi di Sub DAS Waewoki dan menentukan teknik KTA di Sub DAS Waewoki. Untuk memprediksi erosi, diterapkan model SWAT, dengan tahapan deliniasi DAS, pembentukan peta unit lahan, input data iklim serta data pendukung yang dibutuhkan, dan running SWAT. Dari 51 unit lahan di wilayah kajian diambil sampel tanah pada 13 titik lokasi berdasarkan GPS. Untuk merancang teknik KTA digunakan analisis klaster. Hasil penelitian menunjukkan bahwa tingkat erosi yang terjadi pada enam tahun terakhir sangat bervariasi, dari tingkat erosi sangat ringan sebesar 0,11 %, kelas ringan sebesar 1,38 % dan kelas sedang sebesar 1 %. Berdasarkan model regresi ditunjukkan bahwa faktor erosi yang paling berpengaruh di lokasi penelitian adalah kelerengan, yang signifikan terhadap kriteria probabilitas yaitu 0.05. Rancangan teknik KTA dirancang pada jarak tandan terkecil dengan jumlah kelompok klaster sebayak 5 yang memiliki klasifikasi unit lahan yang berbeda-beda. Pengklasteran unit lahan menunjukkan bahwa faktor kelerengan, penggunaan lahan dan jenis tanah merupakan faktor yang paling dominan untuk terbentuknya kelompok klaster I dan V, sedangkan untuk kelompok klaster II, III, dan IV faktor yang paling dominan adalah penggunaan lahan dan jenis tanah. Model KTA yang diterapkan pada setiap kelompok klaster adalah model vegetatif dan mekanik sesuai dengan klasifikasi yang terbentuk.AbstractThe study erosion level and Soil-Water Conservation (SWC) engineering plan was conducted in Waewoki Sub watershed, Aesesa Watershed, Ngada Regency, East Nusa Tenggara Province. This study was aimed at predicting the erosion level in Waewoki Sub watershed and determining Soil and Water Conservation engineering in Waewoki Sub watershed. To predict erosion, SWAT model was applied, with model analysis phases including watershed delineation, land unit map creation, climate data input and supporting data needed, and running SWAT. From the 51 units of land in the study area, the soil samples were collected at 13 locations using GPS. Cluster analysis was used to plan SWC engineering. The results showed that the erosion level occurred in the last six years varied widely, ranging from very mild erosion level of 0.11%, mild level of 1.38%, and medium level of 1%. The statistical test with regression model approach showed that the most influential factor of erosion in the study site was slope, which was significant to the probability criterion, i.e. 0.05. SWC engineering plan was planned in the smallest cluster distance by 5 cluster groups with different land unit classification. Land unit clustering showed that the factors of slope, land use and soil type were the most dominant factors for the formation of the cluster groups I and V, while the most dominant factors for cluster groups II, III, and IV were land use and soil type. The SWC models applied to each cluster group were vegetative and mechanical models, in accordance with the classification formed

Conservation Design and Scenario for Flood Mitigation on Arui Watershed, Indonesia

Flooding has been natural disaster in Indonesia and elsewhere. This research is designed to create scenarios and designs conservation to mitigate flooding disaster.  Data potential ,vulnerability, and duplicated river covering 0.25% of the targeted flooding area were collected and analysed. Five disain of conservation, natural river as control, river normalization, normalization with gabion stone, river straigtening, and straigtening with gabion stone, are proposed, and main targeted responses of these five scenarios are river current velocity. Effectiveness scenarios were analysed using Anova and Tukey test. The results showed that alignment with gabion stone was the most effective scenario for flooding mitigation since this was the most effective in increasing river current velocity. This could prevent riverbank occurrence of avalanche, accelerate river current, overcome flooding, and prevent future flooding. Other scenarios likes dead clicth ended-hallway, canalization, and riparian reclamation are also possible implemented

Multidimensional Scaling Approach to Evaluate the Level of Community Forestry Sustainability in Babak Watershed, Lombok Island, West Nusa Tenggara

Community forestry in Babak watershed is one of the efforts to reduce critical land area. The aim of this research was to evaluate the level of community forestry sustainability in both of community forest (HKm) and private forest in Babak watershed. Multidimensional scaling (MDS) was used to analyse the level of community forest sustainability based on the five dimensions of ecology, economy, social, institutional, and technology as well as 29 attributes. Leverage analysis was used to know the sensitive attributes of sustainability, while Monte Carlo analysis and goodness of fit was used to find the accuracy of MDS analysis. The result shows that HKm was in moderate sustainability level (sustainability index 54.08%) and private forest was in less sustainability level (sustainability index 48.53%). Furthermore, the ecology and technology in HKm were classified as less sustainable, while the institution and technology in private forest were considered less sustainable. There were 11 sensitive attributes of HKm and 19 sensitive attributes of private forest. The priorities of attribute improvement in HKm include land recovering (the dimension of ecology) and cooperative development (the dimension of technology). In private forest, the priorities of attribute improvement include leadership capacity building (the institutional dimension) and also the use of silviculture intensive and soil conservation (the dimension of technology)

A Study of Flood Causal Priority in Arui Watershed, Manokwari Regency, Indonesia

Papua is the final fortress of forests in Indonesia. However, floods recently occurred in Jayapura, Paniai, and Manokwari. If causal factors are not identified and early anticipated, the flood will become an annual disaster with more severe impacts. This study aims to identify main factors causing floods using scoring analysis. Data collected include: rainfall, river gradient, water discharge, drainage density, watershed shape, slope and land use. The research results show that the main factor of floods are average daily rainfall in wet month by 86.53 mm day-1 (rather high) with a score of 28, land use dominated by forest and plantation (rather low and medium) with a score of 21, watershed slope dominated by 1-<8% (high) with a score of 5, drainage density of 6.4 (medium) with a score of 3, watershed shape (Rc of 0.30 < Re 0.71) with  somewhat/elongated shape with a score of 2, and river gradient of 0.0062 (low) with a score of 2 respectively. High rainfall causes greater flow of water and runoff. Land use dominated by plantations (21.46%) is thought to be one of the main causes of floods in Masni District. Flood mitigation does not mean that rain should be reduced, but regulates/manages such as stopping the conversion of forest into palm oil plantations, reducing surface runoff by applying soil conservation, making bypass from meandering, dredging sediments, and constructing retaining walls

A Study of Flood Causal Priority in Arui Watershed, Manokwari Regency, Indonesia

Papua is the final fortress of forests in Indonesia. However, floods recently occurred in Jayapura, Paniai, and Manokwari. If causal factors are not identified and early anticipated, the flood will become an annual disaster with more severe impacts. This study aims to identify main factors causing floods using scoring analysis. Data collected include: rainfall, river gradient, water discharge, drainage density, watershed shape, slope and land use. The research results show that the main factor of floods are average daily rainfall in wet month by 86.53 mm day-1 (rather high) with a score of 28, land use dominated by forest and plantation (rather low and medium) with a score of 21, watershed slope dominated by 1-<8% (high) with a score of 5, drainage density of 6.4 (medium) with a score of 3, watershed shape (Rc of 0.30 < Re 0.71) with  somewhat/elongated shape with a score of 2, and river gradient of 0.0062 (low) with a score of 2 respectively. High rainfall causes greater flow of water and runoff. Land use dominated by plantations (21.46%) is thought to be one of the main causes of floods in Masni District. Flood mitigation does not mean that rain should be reduced, but regulates/manages such as stopping the conversion of forest into palm oil plantations, reducing surface runoff by applying soil conservation, making bypass from meandering, dredging sediments, and constructing retaining walls