DEVELOPMENT OF A LAND DEGRADATION ASSESSMENT MODEL BASED ON FIELD INDICATORS ASSESSMENT AND PREDICTION METHODS IN WAI SARI, SUB-WATERSHED KAIRATU DISTRICT, WESTERN SERAM REGENCY, MALUKU PROVINCE, INDONESIA

2019 ◽  
Vol 2 (1) ◽  
pp. 071-084
Author(s):  
Silwanus M. Talakua ◽  
Rafael M. Osok

The study was conducted in Wai Sari sub-watershed, Western Seram Regency Maluku to develop an accurate land degradation assessment model for tropical small islands. The Stocking’s field land degradation measurement and RUSLE methods were applied to estimate soil loss by erosion and the results of both methods were statistically tested in order to obtain a correction factor. Field indicators and prediction data were measured on 95 slope units derived from the topographic map. The rates of soil loss were calculated according to both methods, and the results were used to classify the degree of land degradation. The results show that the degree of land degradation based on the field assessment ranges from none-slight (4.04 - 17.565 t/ha/yr) to very high (235.44 - 404.00 t/ha/yr), while the RUSLE method ranges from none-slight (0.04-4.59 t/ha/yr) to very high 203.90 - 518.13 t/ha/yr.  However, the RUSLE method shows much higher in average soil loss (133.4 t/ha/yr) than the field assessment (33.9 t/ha/yr). The best regression equation of  logD/RP = - 0.594 + 1.0 logK + 1.0 logLS + 1.0 logC or D = 0.2547xRxKxLSx CxP was found to be a more suitable land degradation assessment  model for a small-scale catchment area in the tropical small islands.

2019 ◽  
Vol 2 (1) ◽  
pp. 071-085
Author(s):  
Science Nature

The study was conducted in Wai Sari sub-watershed, Western Seram Regency Maluku to develop an accurate land degradation assessment model for tropical small islands. The Stocking’s field land degradation measurement and RUSLE methods were applied to estimate soil loss by erosion and the results of both methods were statistically tested in order to obtain a correction factor. Field indicators and prediction data were measured on 95 slope units derived from the topographic map. The rates of soil loss were calculated according to both methods, and the results were used to classify the degree of land degradation. The results show that the degree of land degradation based on the field assessment ranges from none-slight (4.04 - 17.565 t/ha/yr) to very high (235.44 - 404.00 t/ha/yr), while the RUSLE method ranges from none-slight (0.04-4.59 t/ha/yr) to very high 203.90 - 518.13 t/ha/yr.  However, the RUSLE method shows much higher in average soil loss (133.4 t/ha/yr) than the field assessment (33.9 t/ha/yr). The best regression equation of  logD/RP = - 0.594 + 1.0 logK + 1.0 logLS + 1.0 logC or D = 0.2547xRxKxLSx CxP was found to be a more suitable land degradation assessment  model for a small-scale catchment area in the tropical small islands.


2021 ◽  
Vol 10 (1) ◽  
pp. 27
Author(s):  
Bilal Ahmad Munir ◽  
Sajid Rashid Ahmad ◽  
Raja Rehan

In this study, a relation-based dam suitability analysis (RDSA) technique is developed to identify the most suitable sites for dams. The methodology focused on a group of the most important parameters/indicators (stream order, terrain roughness index, slope, multiresolution valley bottom flatness index, closed depression, valley depth, and downslope gradient difference) and their relation to the dam wall and reservoir suitability. Quantitative assessment results in an elevation-area-capacity (EAC) curve substantiating the capacity determination of selected sites. The methodology also incorporates the estimation of soil erosion (SE) using the Revised Universal Soil Loss Equation (RUSLE) model and sediment yield at the selected dam sites. The RDSA technique identifies two suitable dam sites (A and B) with a maximum collective capacity of approximately 1202 million m3. The RDSA technique was validated with the existing dam, Gomal-Zam, in the north of Sanghar catchment, where RDSA classified the Gomal-Zam Dam in a very high suitability class. The SE estimates show an average of 75 t-ha−1y−1 of soil loss occurs in the study area. The result shows approximately 298,073 and 318,000 tons of annual average sediment yield (SY) will feed the dam A and B respectively. The SE-based sediment yield substantiates the approximate life of Dam-A and Dam-B to be 87 and 90 years, respectively. The approach is dynamic and can be applied for any other location globally for dam site selection and SE estimation.


Author(s):  
Carmelo Gugliotta ◽  
Davide Gentili ◽  
Silvia Marras ◽  
Marco Dettori ◽  
Pietro Paolo Muglia ◽  
...  

The aim of the study is to evaluate the preparedness of retirement and nursing homes in the city of Sassari at the end of the first wave of the severe acute respiratory syndrome coronavirus 2 epidemic, first by investigating the risk perception of epidemic outbreaks by the facility managers and subsequently by carrying out a field assessment of these facilities. To perform the field assessment, a checklist developed by the CDC (Infection Prevention and Control Assessment Tool for Nursing Homes Preparing for COVID-19) and adapted to the Italian context was used. Fourteen facilities took part in the survey (87.5%). The application of good practices for each survey area was expressed as a percentage with the following median values: restriction policies (87.5%), staff training (53.8%), resident training (67.6%), availability of personal protective equipment (41.7%), infection control practices (73.5%) and communication (80%). Among the facilities, considerable variability was observed in these evaluation fields: only the restriction policies and communication activities were applied uniformly. A discrepancy was found between perceived risk and real danger in the facilities, requiring targeted communication actions. At present, it is necessary to promote a new approach based on the prediction of critical events, thereby providing the means to effectively address them.


2011 ◽  
Vol 28 (8) ◽  
pp. 1050-1062 ◽  
Author(s):  
Jean Tournadre ◽  
Bertrand Chapron ◽  
Nicolas Reul

Abstract This paper presents a new method to analyze high-resolution altimeter waveforms in terms of surface backscatter. Over the ocean, a basic assumption of modeling altimeter echo waveforms is to consider a homogeneous sea surface within the altimeter footprint that can be described by a mean backscatter coefficient. When the surface backscatter varies strongly at scales smaller than the altimeter footprint size, such as in the presence of surface slicks, rain, small islands, and altimeter echoes can be interpreted as high-resolution images of the surface whose geometry is annular and not rectangular. A method based on the computation of the imaging matrix and its pseudoinverse to infer the surface backscatter at high resolution (~300 m) from the measured waveforms is presented. The method is tested using synthetic waveforms for different surface backscatter fields and is shown to be unbiased and accurate. Several applications can be foreseen to refine the analysis of rain patterns, surface slicks, and lake surfaces. The authors choose here to focus on the small-scale variability of backscatter induced by a submerged reef smaller than the altimeter footprint as the function of tide, significant wave height, and wind.


2022 ◽  
Vol 14 (2) ◽  
pp. 348
Author(s):  
Yashon O. Ouma ◽  
Lone Lottering ◽  
Ryutaro Tateishi

This study presents a remote sensing-based index for the prediction of soil erosion susceptibility within railway corridors. The empirically derived index, Normalized Difference Railway Erosivity Index (NDReLI), is based on the Landsat-8 SWIR spectral reflectances and takes into account the bare soil and vegetation reflectances especially in semi-arid environments. For the case study of the Botswana Railway Corridor (BRC), the NDReLI results are compared with the RUSLE and the Soil Degradation Index (SDI). The RUSLE model showed that within the BRC, the mean annual soil loss index was at 0.139 ton ha−1 year−1, and only about 1% of the corridor area is susceptible to high (1.423–3.053 ton ha−1 year−1) and very high (3.053–5.854 ton ha−1 year−1) soil loss, while SDI estimated 19.4% of the railway corridor as vulnerable to soil degradation. NDReLI results based on SWIR1 (1.57–1.65 μm) predicted the most vulnerable areas, with a very high erosivity index (0.36–0.95), while SWIR2 (2.11–2.29 μm) predicted the same regions at a high erosivity index (0.13–0.36). From empirical validation using previous soil erosion events within the BRC, the proposed NDReLI performed better that the RUSLE and SDI models in the prediction of the spatial locations and extents of susceptibility to soil erosion within the BRC.


2021 ◽  
Vol 4 (2) ◽  
pp. 159-169
Author(s):  
Eko Sumartono ◽  
Gita Mulyasari ◽  
Ketut Sukiyono

Bengkulu is said to be the center of the world's climate because of the influence of water conditions and the topography of the area where the rain cloud formation starts. The waters in Bengkulu Province become a meeting place for four ocean currents which eventually become an area where the evaporation process of forming rain clouds becomes the rainy or dry season and affects the world climate. Method to analyze descriptively, shows oldeman Classification and satellite rainfall estimation data is added. In relation to the Analysis of Potential Food Availability for the Coastal Areas of Bengkulu Province uses a quantifiable descriptive analysis method based. The results show that most are included in the Oldeman A1 climate zone, which means it is suitable for continuous rice but less production due to generally low radiation intensity throughout the year. In an effort to reduce or eliminate the impact of climate change on food crop production, it is necessary to suggest crop diversification, crop rotation, and the application of production enhancement technologies. Strategies in building food availability as a result of climate change are: First, develop food supplies originating from regional production and food reserves on a provincial scale. Second, Empowering small-scale food businesses which are the dominant characteristics of the agricultural economy, especially lowland rice and horticultural crops. Third, Increase technology dissemination and increase the capacity of farmers in adopting appropriate technology to increase crop productivity and business efficiency. Four, Promote the reduction of food loss through the use of food handling, processing and distribution technologies. 


2013 ◽  
Vol 29 ◽  
pp. 1-24 ◽  
Author(s):  
Brian G.J. Upton

The 1300–1140 Ma Gardar period in South Greenland involved continental rifting, sedimentation and alkaline magmatism. The latest magmatism was located along two parallel rift zones, Isortoq–Nunarsuit in the north and the Tuttutooq–Ilimmaasaq–Narsarsuaq zone in the south addressed here. The intrusive rocks crystallised at a depth of troctolitic gabbros. These relatively reduced magmas evolved through marked iron enrichment to alkaline salic differentiates. In the Older giant dyke complex, undersaturated augite syenites grade into sodalite foyaite. The larger, c . 1163 Ma Younger giant dyke complex (YGDC) mainly consists of structureless troctolite with localised developments of layered cumulates. A layered pluton (Klokken) is considered to be coeval and presumably comagmatic with the YGDC. At the unconformity between the Ketilidian basement and Gardar rift deposits, the YGDC expanded into a gabbroic lopolith. Its magma may represent a sample from a great, underplated mafic magma reservoir, parental to all the salic alkaline rocks in the southern rift. The bulk of these are silica undersaturated; oversaturated differentiates are probably products of combined fractional crystallisation and crustal assimilation. A major dyke swarm 1–15 km broad was intruded during declining crustal extension, with decreasing dyke widths and increasing differentiation over time. Intersection of the dyke swarm and E–W-trending sinistral faults controlled the emplacement of at least three central complexes (Narssaq, South Qôroq and early Igdlerfigssalik). Three post-extensional complexes (Tugtutôq, Ilímaussaq and late Igdlerfigssalik) along the former rift mark the end of magmatism at c . 1140 Ma. The latter two complexes have oblate plans reflecting ductile, fault-related strain. The Tugtutôq complex comprises quartz syenites and alkali granites. The Ilímaussaq complex mainly consists of nepheline syenite crystallised from highly reduced, Fe-rich phonolitic peralkaline (agpaitic) magma, and resulted in rocks with very high incompatible element concentrations. Abundant anorthositic xenoliths in the mafic and intermediate intrusions point to a large anorthosite protolith at depth which is considered of critical importance in the petrogenesis of the salic rocks. Small intrusions of aillikite and carbonatite may represent remobilised mantle metasomites. The petrological similarity between Older and Younger Gardar suites implies strong lithospheric control of their petrogenesis. The parental magmas are inferred to have been derived from restitic Ketilidian lithospheric mantle, metasomatised by melts from subducting Ketilidian oceanic crust and by small-scale melt fractions associated with Gardar rifting. There are numerous analogies between the southern Gardar rift and the Palaeogene East African rift.


Author(s):  
Tina Unglaube ◽  
Hsiao-Wei D. Chiang

In recent years closed loop supercritical carbon dioxide Brayton cycles have drawn the attention of many researchers as they are characterized by a higher theoretic efficiency and smaller turbomachinery size compared to the conventional steam Rankine cycle for power generation. Currently, first prototypes of this emerging technology are under development and thus small scale sCO2 turbomachinery needs to be developed. However, the design of sCO2 turbines faces several new challenges, such as the very high rotational speed and the high power density. Thus, the eligibility of well-established radial inflow gas turbine design principles has to be reviewed regarding their suitability for sCO2 turbines. Therefore, this work reviews different suggestion for optimum velocity ratios for gas turbines and aims to re-establish it for sCO2 turbines. A mean line design procedure is developed to obtain the geometric dimensions for small scale sCO2 radial inflow turbines. By varying the specific speed and the velocity ratio, different turbine configurations are set up. They are compared numerically by means of CFD analysis to conclude on optimum design parameters with regard to maximum total-to-static efficiency. Six sets of simulations with different specific speeds between 0.15 and 0.52 are set up. Higher specific speeds could not be analyzed, as they require very high rotational speeds (more than 140k RPM) for small scale sCO2 turbines (up to 150kWe). For each set of simulations, the velocity ratio that effectuates maximum efficiency is identified and compared to the optimum parameters recommended for radial inflow turbines using subcritical air as the working fluid. It is found that the values for optimum velocity ratios suggested by Rohlik (1968) are rather far away from the optimum values indicated by the conducted simulations. However, the optimum values suggested by Aungier (2005), although also established for subcritical gas turbines, show an approximate agreement with the simulation results for sCO2 turbines. Though, this agreement should be studied for a wider range of specific speeds and a finer resolution of velocity ratios. Furthermore, for high specific speeds in combination with high velocity ratios, the pressure drop of the designed turbines is too high, so that the outlet pressure is beyond the critical point. For low specific speeds in combination with low velocity ratios, the power output of the designed turbines becomes very small. Geometrically, turbines with low specific speeds and high velocity ratios are characterized by very small blade heights, turbines with high specific speeds and small velocity ratios by very small diameters.


Author(s):  
X. Gao ◽  
B. Li ◽  
X. Zhou

Spring and Autumn period, the vassal states began to carry out country defense construction actively, brought changes to building the ideological. At that time, the south region of Shandong, as an independent unit of geography, seldom affected by external factors, and had striking cultural characteristics. Vassal states there constructed their capital mainly to defense the neighboring countries and cope with small scale mergers war, not involving the nationwide military deployment. Therefore, the region reflect the construction thought changes during the Spring and Autumn Period, and consistent with the research purpose. Based on this judgment, the author analyzed each capital’s location and terrain feature by topographic map. In brief, the Spring and Autumn Period, feudal states acted of one's own free will, the relationship between cities contained the one within and between vassal states. Within vassal state relationships included economic support, entrenching each other and protecting the country together. Meanwhile, strategic defensing, scrambling for resources and geographical location comprised of the competition between vassal states. In the agrarian age, the political centers and agricultural areas were interdependent, giving priority to the development of political cities. Transformation of capitals’ space layout was actually the process of carving up farming plains, the powerful states occupy favorable geographical position, and the small countries would be encroached and annexed gradually.


Author(s):  
Yusnarida Eka Nizmi ◽  
Yessi Olivia ◽  
Umi Oktyari Retnaningsih ◽  
M. Saeri ◽  
Ahmad Jama’an ◽  
...  

This study analyses the implementation of good governance principles for the economic revitalization program under Riau Province’s Badan Restorasi Gambut (Peatland Restoration Agency) supervision. One of the aims of this program is to support the haze-free ASEAN 2020 roadmap. Riau province is an area prone to forest fire disasters. Its peatland area,  which is twice as large as Malaysia’s peatland, have a very high potential for damage due to forest fires. To mitigate the damages, BRG initiated the 3R program: Rewetting, Revegetation, and Revitalization. What makes this topic interesting is BRG emphasizes the aspects of economic empowerment of local communities to prevent further forest and peatland damages. To assess the implementation of BRG’s program, our research team conducted several interviews with representatives from Indonesia’s Ministry of Environment and Forestry, NGOs, academics, farmers, and villages’ facilitators who assisted local communities that received the BRG’s assistance packages. Our study shows that BRG’s economic revitalization program had succeeded in creating small scale economic activities such as honey industry, pineapple farming, and catfish farming. However, the ineffective coordination and communication between BRG and the local communities had prevented them from constructing an effective method to prevent future forest fires.


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