Kajian Tingkat Aliran Permukaan dan Erosi, pada Berbagai Tipe Penggunaan Lahan di Sub DAS Jenneberang Hulu

The objective of this research was to evaluate and assess the level of run-off and erosion on various types of land use in the Upper Jenneberang Sub Watershed. This research was conducted in the Upper Jenneberang Sub Watershed, Saluttoa Village, Sub Tinggimoncong, Gowa regency, South Sulawesi Province. Land use type (LUT) which was used as land units of observations was determined based on land use maps of upper Jenneberang sub watershed. Based on the analysis results of map and observation in the field, it was defined four types of land use as land units of observation: 1) Natural forest, 2) Gliricidia tree-dominated agroforestry, 3) Coffee tree-dominated agroforestry, and 4) Maize monoculture. Each LUT was given the observation plot size 30 m x 10 m and plot placement was determined randomly. All LUT had slope 26%, soil type of Brown Latosol at the same altitude and climate. The composition of the observation plot was based on Randomized Block Design (RBD). Collected data on LUT included: soil physical properties, infiltration rate, run-off and erosion. The result showed that changes in land use of natural forests into agroforestry and maize monoculture types resulted in decreased amount of woody vegetation that resulted in increased run-off and erosion

Land Use Planning of Way Betung Watershed for Sustainable Water Resources Development of Bandar Lampung City

Way Betung watershed is one of the important water resources in Lampung Province and it provides a clean water for Bandar Lampung City through a regional water supply company (PDAM). By the increase of population and economical activities of Bandar Lampung City, the need of clean water also increase, however by the time, the conditions of Way Betung watershed as water resources are declining. Therefore, to improve or to restore WayBetung watershed, a high cost is needed. The research was aimed: (a) to study the effects of Way Betung watershed land use change on the water resources of Bandar Lampung City, (b) to arrange the sustainable development of Way Betung watershed in order to maintain the availability of water resources. The sustainable developments of water resources of Way Betung watershed were arranged in five alternatives/scenarios and each alternative was related toits erosion (USLE method) and its run off volume (SCS method). The results showed that land use changes of Way Betung watershed (1991-2006) were likely to increase daily maximum discharge (Q max), to decrease daily minimum discharge (Q min), to increase fluctuation of river discharge, and to increase yearly run off coeffcient. The best sustainable development of water resources of Way Betung watershed, Lampung Province, was alternative/scenario-4 (forest as 30% of watershed areas + alley cropping in the mix garden). This alternative will decrease erosion to the level lower than tolerable soil loss and also decrease fluctuation of monthly run off

Valuasi Manfaat Ekologis Ruang Terbuka Hijau (Rth) Di Kota Bogor Dengan Aplikasi Citygreen 5.4

Greenery open space is a fundamental part of urban development and management in sustaining the quality of urban environment and the welfare of urban dwellers. A high rate of population growth and limited land owned causing the growth of physical development in the city is done by converting such green open space, agricultural land, forest and other open space for urban development purposes. This study is intended to analyze total value of greenery open space ecological benefits of Bogor City, and provide possible recommendations in order to increase the capacity of its urban ecosystem. This analytical framework is applied to Bogor City considering its peculiarities of greenery open space existence and architectures. The research was conducted by spatial approach through CITYGreen 5.4 software to determine the ecological benefits of greenery open space, based on the trees canopy cover and non trees canopy cover to predict the economic value. CityGreen is a software tool developed by American Forest that helps people understand the value of trees to the local environment. The result showed that CITYGreen 5.4 software can be used to conduct complex analysis of ecosystem services and create easy to understand reports.The software calculate dollar benefits for the services provided by the trees and other greenery open space in absorbed such harmfull pollutants, carbon storage and sequestration, and reducing storm water volumes as natural flood control. The capacity of ecological benefit can still be improved to provide greater benefits in various ways. This software will be very beneficial for city planners in evaluate site plan, and model development scenario that capture the benefits of trees

Watershed Modeling with ArcSWAT and SUFI2 in Cisadane Catchment Area: Calibration and Validation of River Flow Prediction

Increasing of natural resources utilization as a result of population growth and economic development has caused severe damage on the watershed. The impacts of natural disasters such as floods, landslides and droughts become more frequent. Cisadane Catchment Area is one of 108 priority watershed in Indonesia. SWAT is currently applied world wide and considered as a versatile model that can be used to integrate multiple environmental processes, which support more effective watershed management and the development of better informed policy decision. The objective of this study is to examine the applicability of SWAT model for modeling mountainous catchments, focusing on Cisadane catchment Area in west Java Province, Indonesia. The SWAT model simulation was done for the periods of 2005 – 2010 while it used landuse information in 2009. Methods of Sequential Uncertainty Fitting ver. 2 (SUFI2) and combine with manual calibration were used in this study to calibrate a rainfall-runoff. The Calibration is done on 2007 and the validation on 2009, the R2 and Nash Sutchliffe Efficiency (NSE) of the calibration were 0.71 and 0.72 respectively and the validation are 0.708 and 0.7 respectively. The monthly average of surface runoff and total water yield from the simulation were 27.7 mm and 2718.4 mm respectively. This study showed SWAT model can be a potential monitoring tool especially for watersheds in Cisadane Catchment Area or in the tropical regions. The model can be used for another purpose, especially in watershed management

Kajian Kemampuan Lahan pada Usahatani Lahan Kering Berbasis Tembakau di Sub-DAS Progo Hulu

Title : The Study of Land Capability on Tobacco-Based Upland Farming at Progo Hulu Sub-Watershed. The recent and also the future problems for Indonesian concerning with agricultural environment resources are land degradation and water resources restrictiveness. Agricultural technique without awareness to concerning to soil and water conservation principles on steep and high rainfall area had caused severe erosion and land degradation at upland area of Progo Hulu sub-watershed. Land Degradation that promoted by erosion at Progo Hulu sub-watershed contributed negative effects at on-site and out-site area. The land capability analysis shows that tobacco-based farming system at Progo Hulu sub watershed dominated by class IV (3,624.93 ha; 49.00%), followed with class VI (2,488.82 ha; 33.64%), class III (697.99 ha; 9.43%), class V (450.73 ha; 6.09%), and class VII (136.06 ha; 1.84%). The main resistance factors are slope and erosion for class III; erosion, slope and surface rocks for class VI; and slope for class VII

LAND CAPABILITY EVALUATION FOR LAND USE RECOMMENDATION IN LAWO WATERSHED

The changes of forest uses into agricultural land is a serious problem in Lawo watershed, South Sulawesi. Agricultural practices without implementing soil conservation and adequate agro-technology has caused high level of soil erosion and low land productivity. Management in Lawo watershed must be done with integrated soil and water conservation in order to increase agricultural production. This effort can be done with land capability evaluation. The purpose of this study is to evaluate the land capability of Lawo watershed using land capability category for data analysis. The results showed that Lawo watershed is dominated by land capability of class III with erosion (middle) as the dominant limiting factor which covers about 17,476.42 ha (49.68%). In addition, the class of land capability is followed by class IV with the slope (moderately steep) as the limiting factor and erodibility of soil (middle) covering about 10,059.8 ha (28.6%), land capability of class VI with slope (Steep) as the limiting factor with 7,638.32 ha (21.72%) coverage area. Land with class III can be recommended for dryland farming with adequate application of agro-technology, and water and soil conservation. While class IV and VI are not recommended for agricultural activities but for private forest or plantation fores

Analisis Alternatif Penggunaan Lahan untuk Menjamin Ketersediaan Air di DAS Konaweha Provinsi Sulawesi Tenggara

Title : The Analysis of Land Use Alternatives to Ensure Water Supply at Konaweha Watershed Southeast Sulawesi Province. Fenomena of decreasing water supply and increasing water demand occurred at Konaweha watershed. Konaweha watershed shed is a priority watershed in Southeast Sulawesi Province due to its crucial function. Land use changes were suspected to be the cause of decreasing water supply. One effect of this condition was maximum discharge increase and minimum discharge decrease of Konaweha River resulted in water deficit. Research objectives were (1) to evaluate the effect of land use changes on hydrologic condition of Konaweha watershed; (2) to evaluate the water supply and water demand as well as supply and demand water balance at Konaweha watershed, and (3) to formulate land use alternatives and management policy of Konaweha watershed. This research had been conducted at Konaweha watershed for 10 months e.g. from June 2009 to March 2010. The average declining of forest width during 1991‐1999 was 1.25 percent/year, 2001‐2005 was 0.52 percent/year and 2006‐2011 was 0.90 percent/year. In the same time the availability of minimum discharge as a water supply was decrease. There was no deficit on annual water supply until 2050 but monthly distribution of hydrograph caused water deficit in September started from 2016. Proportion of maintenance cost for watershed function at Kendari Municipality was 35 percent while at the District of Konawe, South Konawe and Kolaka were 28 percent, 15 percent, and 22 percent respectively from total economic value of water at Konaweha watershed. Forest economic value including flora and fauna, carbon absorption, option value, bequest value and existence value was IDR 14,974,716/hectare. Five alternative of land use at Konaweha watershed were: (1) Scenario 1: 30 percent forest, 45 percent plantation, 6 percent mix garden and 1 percent bush; (2) Scenario 2: 35 percent forest, 45 percent plantation, 5 percent mix garden and 1 percent bush; (3) Scenario 3: 44 percent forest, 35 percent plantation, 5 percent mix garden and 1 percent bush; (4) Scenario 4: 34 percent forest, 45 percent plantation, 7 percent mix garden and 1 percent bush; and (5) Scenario 5: 40 percent forest, 35 percent plantation, 5 percent mix garden and 2 percent bush. Scenario 4 were not appropriate while scenario 1, 2, 3 and 5 were appropriate to applied in upper Konaweha watershed. Scenario 3 with a minimal of 44 percent of forest was the best land use alternative