Study of bathymetry in determining Nuclear Power Plant Site in Gosong Beach Waters, West Kalimantan

Gosong Beach waters are located in Bengkayang Regency West Kalimantan, where the water conditions are influenced by the South China Sea. This study aimed to determine the shape of the bottom morphology profile (bathymetry). The bottom morphology of the water was used as initial data to determine the location of nuclear sites in the study area. Bathymetry measurements were conducted using a single beam echosounder corrected by tidal data to determine the chart datum value, then used to correct sea depth for accuracy. The measurement of tidal data was conducted for 15 days in March 2021 with an interval of 1 hour. The results showed that the type of tidal obtained was mixed tide mixed with the double daily slope with Formzhal (F) value 0.77. The depth of the waters at the study site ranges from 0.9 to 8.45 meters. The average value of the coastal slope shows that spatially there are variations in the slope class with the percentage value ranging from 0.13 to 2.29% which is included in the classification of flat coastal slopes.

Valuasi Dampak Banjir Di Kabupaten Landak, Kalimantan Barat

Banjir merupakan becana yang kerap sekali terjadi pada musim hujan, banjir dapat menyebabkan kehilangan harta benda maupun korban jiwa. Valuasi ekonomi akibat terjadinya banjir adalah salah satu cara yang dapat digunakan untuk menghitung kerugian akibat terjadinya bencana banjir. Tidak adanya kajian mengenai kerentanan dan kerugian ekonomi akibat banjir pada tiga desa di Kecamatan Ngabang yaitu Desa Raja, Hilir Tengah dan Hilir Kantor adalah alasan dilakukannya penelitian ini. Tujuan dilakakukan penelitian ini adalah untuk mengidentifikasi dan menginventarisasi besarnya tingkat kerentanan terhadap banjir yang terjadi dan menghitung valuasi kerugian ekonomi akibat terjadinya bencana banjir. Metode yang digunakan dalam menganalisis kerentanan banjir menggunakan software ArcMap 10.3 adalah Analisa atribut meliputi pemberian skor kelas curah hujan, pemberian skor kelas tutupan lahan, pemberian skor kelas kemiringan lahan, pembobotan dan Analisa AHP. Metode yang digunakan untuk menghitung estimasi kerugian akibat banjir menggunakan metode ECLAC. Hasil yang didapat dalam penelitian ini adalah perubahan tutupan lahan mengalami penurunan dan peningkatan luasan permukiman, pertanian/sawah, dan lahan terbuka/semak, Curah hujan yang tinggi dan kelerengan daerah yang landai menjadi parameter penyebab terjadinya banjir. Pada estimasi nilai kerugian akibat banjir dengan nilai kerugian menggunakan USD dan Emas pada tahun yang ditentukan dengan hasil total kerugian pada tahun 1973 adalah 73,7 Juta dollar, tahun 1989 180 juta dollar, tahun 1994 261 juta dollar, tahun 2000 261juta dollar, tahun 2010 1,1 miliar dollar, dan tahun 2020 1,9 miliar dollar.ABSTRACTFlood is a plan that often occurs in the rainy season, floods can cause loss of property and fatalities. Economic valuation due to flooding is one way that can be used to calculate losses due to flood disasters. The absence of studies on vulnerability and economic losses due to flooding in three villages in Ngabang Subdistrict namely Desa Raja, Hilir Tengah and Hilir Kantor is the reason for this research. The purpose of this study is to identify and inventory the level of vulnerability to floods that occur and calculate the valuation of economic losses due to flood disasters. The methods used in analyzing flood vulnerabilities using ArcMap 10.3 software are attribute analysis including rainfall class scoring, giving land cover class scores, awarding land slope class scores, weighting and AHP Analysis. The method used to calculate the estimated loss due to flooding uses the ECLAC method. The results obtained in this study are changes in land cover experiencing a decrease and increase in the area of settlements, agriculture / rice fields, and open land / bush, high rainfall and marbles of sloping areas become parameters of the cause of flooding. In the estimated value of losses due to floods with the value of losses using USD and Gold in the specified year with the total loss in 1973 was 73.7 million dollars, in 1989 180 million dollars, in 1994 261 million dollars, in 2000 261 million dollars, in 2010 1.1 billion dollars, and in 2020 1.9 billion dollars.

Evaluasi Kemampuan Lahan di Desa Sungai Jelayan Kecamatan Kedawangan Kabupaten Ketapang

Sungai Jelayan Village is one of the villages in Kendawangan District, Ketapang Regency, which still has the potential for sustainable management. Evaluation of land capability is one of the efforts to overcome the reduction of land degradation. Land capability is an assessment of land units for particular uses, assessed from each inhibiting factor. This study aimed to determine the characteristics of the land according to the land capability parameter, assessed the land capability sub-class, and provided suggestions for land use based on the land capability sub-class in Sungai Jelayan Village. The research stages started from preparation, preliminary survey, determination of research location based on land units consisting of soil type, slope class, land use and there were 9 land units, and determination of observation points, as well as field observations and soil sampling, laboratory analysis, data processing and presentation of results. The results obtained 2 soil orders, namely Entisols and Inceptisols. The results of the land capability evaluation were divided into five land capability classes and sub-classes, namely class II-s, III-s, IV-w, V-w, and VIII-es. Improvement efforts or efforts to use land sustainably could be carried out in 5 ways, namely intensive cultivation, moderate cultivation, limited cultivation, nature reserves/protected forests, and intensive grazing.

The effect of slope aspect on growth attributes of Shorea leprosula Miq. in a rehabilitated hilly landscape

Shorea leprosula Miq. is one of Indonesia’s native red meranti species with a higher growth increment than other meranti species. Gunung Dahu Research Forest is a rehabilitated hilly landscape planted with various species of Dipterocarpaceae. This study aims to analyze the growth performance of 24 years old of S. leprosula stands in various slope classes of line planting technique at Gunung Dahu Research Forest. Growth analysis of S. leprosula was carried out by measuring the stem diameter, total tree height, basal area, diameter increment, height increment, and Leaf Area Index (LAI). Slopes were divided into three classes: mild/gentle (15-25%), steep (>25-45%) and very steep (>45%). The results showed that slope class significantly affected height growth and the canopy cover of S. leprosula, but it did not affect the diameter growth. A very steep slope provided the best growth to diameter (average diameter 30.07 cm; MAI 1.25 cm/year) and height (average height 23.7 m; MAI 0.99 m year−1). Furthermore, a linear relationship was formed between the crown cover and slope class in which denser crowns were established in response to a steeper slope (LAI 3.4). Thus, planting S. leprosula as a rehabilitation effort in steep slope landscape delivers beneficial as they showed better growth performance.

The growth Shorea leprosula Miq. on various slopes and directions of slopes in Gunung Dahu Research Forest, Bogor

Shorea leprosula Miq is a Dipterocarps forest plantation that has the prospect of being developed because it is a fast-growing species with high economic value. Given its commercial importance, this study was conducted to analyze the effect of slope class and slope direction on growth. Data were collected using the census method on S.leprosula stands with a spacing of 2m x 2m and 4m x 8m. The direction of the slope is determined based on the configuration of the slope according to the cardinal directions, while the slope of the land is determined based on the classification of the slope class of the land. The results showed that the slope class, slope direction, and the interaction between factors had a significant effect on the growth of S.leprosula. The interaction between the slope class and the direction of the slope produces the highest average annual increment of diameter in the flat slope class with the direction of the slope facing north, which is 1.79 m / year while the highest annual increment of the total average height is in the very steep slope class with to the slope facing to the north at 0.82 m / year.

Effect of Feller-Buncher Model, Slope Class and Cutting Area on the Productivity and Costs of Whole Tree Harvesting in Brazilian Eucalyptus Stands

The operational productivity and costs of tree felling operations can be influenced by several factors, among which, the machine characteristics, slope class, the cutting area and the individual volume of the trees stand out. Thus, the main objective of the present study was to analyze the productivity and production cost for two feller-bunchers with different technical characteristics operating in a eucalyptus forest. The productivity was calculated from a time study and the factors analyzed were two feller-buncher models, two slope classes, and two cutting areas. The machine cost per scheduled hour was based on the methodology of the Food and Agriculture Organization of the United Nations. Analysis of the results showed that the felling and turn operational elements occupied the most time in the operational cycle of feller-bunchers. The machine cost per scheduled hour was USD 69.69 h−1 for feller-buncher 1 and USD 102.03 h−1 for feller-buncher 2. In conclusion, the distinct technical characteristics of feller-bunchers were found to influence the productivity and, consequently, the cost, of the felling operation during the harvesting of whole eucalyptus trees.

ANALISIS SPASIAL SEBARAN LAHAN KRITIS DI KPHP UNIT XII BATANGHARI PROVINSI JAMBI

Critical land occured as a result of land cover changes from vegetated into non vegetated land or the composition of the vegetation has changed. This study aimed to analyze the distribution of land critical at KPHP Unit XII Batanghari. Critical land analysis was based on the Perdirjen PDASHL Number P.3/PDASHL/SET/KUM.1/7/2018. Land is classified into 5 levels of criticality, namely: non-critical, critical potential, somewhat critical, critical and very critical. The parameters used in determining the level of criticality of the land are: land cover, erosion-prone class, slope class and the presence of land inside or outside the forest function. Spatial analysis used by Geographic Information System (GIS) and remote sensing technology. GIS is able to analyze and represent geographic phenomenon. Landsat 8 imagery was analyzed to obtain land cover clasification. The results of the analysis showed that critical land level of KPHP Unit XI Batanghari consisted of 3,609 ha (4.45%) that classified as very critical and 3,599 ha (4,43%) as critical land. Then, land with a somewhat critical level had the largest area, namely 26,024 ha or 32.07% of the total area of KPHP Unit XII Batanghari. The landcover was the main parameter to determine the level of criticality of the land. The openland cover type had the maximum score 60.

Beach slope distribution mapping using UAV in the Cirebon coastal area

The beach slope is usually estimated using the conventional ground survey, causing the availability of this parameter data to be limited in some areas. Meanwhile, this parameter is considered crucial in the study of shoreline changes and coastal area protection as well as other coastal morphodynamic research. The aim of this study is to demonstrate an efficient technique to calculate the beach slope as well as its distribution in an area. In the daily intertidal period, the beach profile is assumed to be a static planar beach state which does not change due to the insignificant effect of erosion and accretion process. First, the shoreline data set was delineated from the tidal-varied orthomosaic using the UAV. The beach slope is then calculated by comparing the difference in tide level with the difference in the horizontal distance of shoreline points along a cross-shore transect at different times. The utilization of UAV allows mapping the shoreline in an area in several different tidal conditions, allowing the distribution of the beach slope also be mapped. This technique was then applied in the Cirebon Coastal Area and found an average beach slope of 0.105 with 0.100 being the slope class with the highest number of distributions. It was also found that due to the presence of mangroves and coastal structures, no slope conditions dominated this area. The result of beach slope calculation using this technique shows suitability with other studies and reveals UAVs’ potential in mapping the beach slope distribution more efficiently.

Assessment of Rock Slope Stability along Sulaimaniyah -Qaradagh Main Road, Near Dararash Village, Sulaimaniyah, NE-Iraq

The road network in the Baranan mountain, near Dararash village, connecting Sulaymaniyah city with Qaradagh town, plays a major role in socio- economic activities of Qaradagh town and its surrounding villages. Any type of slope failure in the area may cause breaking up in traffic, loss of lives, and injuries. For assessing the stability of rock slopes in the area, seven stations (rock-cut slopes) were selected along the road and evaluated by kinematic analysis, using DIPS v6.008 software and slope mass rating system (SMRTool - v205 software). The kinematic analysis revealed that planar and wedge sliding may occur in stations no.2, 5, 6, and 7, flexural toppling may occur in station no.1, direct toppling may occur in station no.2, and oblique toppling may occur in station no.3. SMR- Tool software for discrete-SMR and continuous-SMR (CSMR) revealed that stations no.2, 5, 6 and 7 are unstable slopes (class IV of a bad slope type) with failure probability of 0.6, with an exception for station no.7 which is a partially stable slope (class III of a normal slope type) with failure probability of 0.4. Station no.1 is partially stable slope (class III of a normal slope type) with failure probability of 0.4 and station no.3 is stable slope (class II of a good slope type) with failure probability of 0.2. Due to the lack of structural and failure surface data (attitude of discontinuities and slumping surface) in station no.4, stability analysis was interpreted by using the general conventional method, depending on the field criterion and vision. The station can be interpreted as a rotational failure, the upper part of which consists of slump motion and the lower part of flow motion.

Efficiency of some conservation treatments for soil erosion control on unallowable slopes of skid trails

The aim of this study was to determine the suitable conservation treatments to control water erosion from skid trails in ShastKalate forests. Two longitudinal slopes of 20-40% and > 40% were considered as critical slopes for skid trails. Treatments of water diversion ruts, water diversion ruts filled with slash and stones were implemented on each slope. A rubber bar was installed at the end of the slope to convert runoff into collectors. Sampling was done during rainfall events in autumn and winter seasons. Findings indicated that the treatment of water diversion ruts filled with slash was better than the other treatments in the control of sediment and soil loss, especially in the slope class of 20–40%. In the slope class of > 40%, there was not any significant difference between treatments in sediment and soil loss control, but generally water diversion ruts filled with slash and stones were better in soil erosion control than water diversion ruts. In both slope classes, the rainfall intensity of 0.11 mm·h^–1 (2.64 mm in 24 h) was the threshold of soil erosion on skid trails. The control of water erosion of soil on skid trails by the operation of water diversions is a suitable treatment for conserving skid trails.