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Temporal and spatial variation and prediction of water yield and water conservation in the Bosten Lake Basin based on the PLUS-InVEST model
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作者 CHEN Jiazhen KASIMU Alimujiang +3 位作者 REHEMAN Rukeya WEI Bohao HAN Fuqiang ZHANG Yan 《Journal of Arid Land》 SCIE CSCD 2024年第6期852-874,共23页
To comprehensively evaluate the alterations in water ecosystem service functions within arid watersheds,this study focused on the Bosten Lake Basin,which is situated in the arid region of Northwest China.The research ... To comprehensively evaluate the alterations in water ecosystem service functions within arid watersheds,this study focused on the Bosten Lake Basin,which is situated in the arid region of Northwest China.The research was based on land use/land cover(LULC),natural,socioeconomic,and accessibility data,utilizing the Patch-level Land Use Simulation(PLUS)and Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)models to dynamically assess LULC change and associated variations in water yield and water conservation.The analyses included the evaluation of contribution indices of various land use types and the investigation of driving factors that influence water yield and water conservation.The results showed that the change of LULC in the Bosten Lake Basin from 2000 to 2020 showed a trend of increasing in cultivated land and construction land,and decreasing in grassland,forest,and unused land.The unused land of all the three predicted scenarios of 2030(S1,a natural development scenario;S2,an ecological protection scenario;and S3,a cultivated land protection scenario)showed a decreasing trend.The scenarios S1 and S3 showed a trend of decreasing in grassland and increasing in cultivated land;while the scenario S2 showed a trend of decreasing in cultivated land and increasing in grassland.The water yield of the Bosten Lake Basin exhibited an initial decline followed by a slight increase from 2000 to 2020.The areas with higher water yield values were primarily located in the northern section of the basin,which is characterized by higher altitude.Water conservation demonstrated a pattern of initial decrease followed by stabilization,with the northeastern region demonstrating higher water conservation values.In the projected LULC scenarios of 2030,the estimated water yield under scenarios S1 and S3 was marginally greater than that under scenario S2;while the level of water conservation across all three scenarios remained rather consistent.The results showed that Hejing County is an important water conservation function zone,and the eastern part of the Xiaoyouledusi Basin is particularly important and should be protected.The findings of this study offer a scientific foundation for advancing sustainable development in arid watersheds and facilitating efficient water resource management. 展开更多
关键词 PLUS model InVEST model Bosten Lake Basin water yield water conservation land-use simulation Geodetector
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Load Static Models for Conservation Voltage Reduction in the Presence of Harmonics
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作者 William Douglas Caetano Patrícia Romeiro da Silva Jota 《Energy and Power Engineering》 2016年第2期62-75,共14页
The Conservation Voltage Reduction (CVR) is a technique that aims to achieve the decrease of power consumption as a result of voltage reduction. The customer is supplied with the lowest possible voltage level compatib... The Conservation Voltage Reduction (CVR) is a technique that aims to achieve the decrease of power consumption as a result of voltage reduction. The customer is supplied with the lowest possible voltage level compatible with the stipulated level by the regulatory agency. International Standards ANSI C84.1-2006 and IEEE std 1250-1995 specify the range of supply voltage to electronics equipment from 0.9 to 1.05 pu of nominal voltage. To analyse the CVR effect in distribution systems with different load characteristics (residential, commercial, industrial or a combination of these), mathematical load models are used. Typically, these equipment/load models are used to analyse load aggregation without any consideration of its nonlinearity characteristics. Aiming to analyse the nonlinear characteristics and its consequences, this paper presents a discussion of the neglected variables as well as the results of a set of measurements of nonlinear loads. Different mathematical models are applied to obtain them for each load. Using these models the load aggregation is evaluated. It is presented that although the models show adequate results for individual loads, the same does not occur for aggregated models if the harmonic contribution is not considered. Consequently, to apply the load model in CVR it is necessary to consider the harmonics presence and the model has to be done using only the fundamental frequency data. The discussion about the causes is done and the models are compared with the measurements. 展开更多
关键词 CVR Load model in the Presence of Harmonics conservation Voltage Reduction Load model Aggregation in the Presence of Harmonics
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Using MaxEnt Model to Guide Marsh Conservation in the Nenjiang River Basin, Northeast China 被引量:6
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作者 WANG Zhiliang ZHANG Bai +1 位作者 ZHANG Xuezhen Tian Hongxu 《Chinese Geographical Science》 SCIE CSCD 2019年第6期962-973,共12页
Incorporating private and working lands into protected area networks could mitigate the isolation state of protected areas(PAs) and improve the efficiency of conservation.But how to select patches of land for conserva... Incorporating private and working lands into protected area networks could mitigate the isolation state of protected areas(PAs) and improve the efficiency of conservation.But how to select patches of land for conservation is still a troublesome issue.In this study, the MaxEnt model and irreplaceability index were applied to guide marsh conservation in the Nenjiang River Basin, Northeast China.According to the high accuracy of the MaxEnt model predictions(i.e., the average AUC value = 0.933), the Wuyuer River and Zhalong marshes in the downstream reaches of Wuyuer River are the optimal habitat for the Red-crowned crane and migratory waterfowls.There are 22 marsh patches selected by the patch irreplaceability index for conservation, of which 12 patches had been included in the current network of protected areas.The other 10 patches of marsh(amounting to 1096 km^2) far from human disturbances with high NDVI(up to 0.8) and close distance to water(less than 100 m), which are excluded from the existing network of PAs, should be implemented conservation easement programs to improve the protection efficiency of conservation.Specifically, the marshes at Taha, Tangchi, and Lamadian should be given priority for conservation and restoration to reintroduce migratory waterfowls, as this would lessen the current isolation state of the Zhalong National Nature Reserve. 展开更多
关键词 MAXENT model IRREPLACEABILITY index MARSH conservation Red-crowned crane(Grus japonensis) Nenjiang River Basin
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Influence of ecological function protection zone on the water conservation in Gansu-Qinghai Contiguous Region of the upper Yellow River
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作者 TONG Huali CHEN Qingbo ZHANG Xuan 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1345-1357,共13页
The implementation of Ecological Function Protection Zone(EFPZ)policy is significant for the ecological restoration and conservation of soil and water in the territory space.This manuscript analyzed and quantified the... The implementation of Ecological Function Protection Zone(EFPZ)policy is significant for the ecological restoration and conservation of soil and water in the territory space.This manuscript analyzed and quantified the impact of EFPZ on the regional water conservation function,based on land use data from 2005,2008,2010,2015 and 2020,by conducting a counterfactual simulation along with the GeoSOS-FLUS model and the InVEST model.The results demonstrate that the delineation of EFPZ can significantly influence the water conservation.(1)From 2010 to 2020,as the EFPZ was implemented,the water conservation in the study area was increasing year by year,with a growth rate of 0.03×10^(8) m^(3)∙a^(-1).On the other hand,the simulated water conservation capacity without the implementation of EFPZ decreased year by year,with a decrease rate of 0.01×10^(8) m^(3)∙a^(-1).(2)The EFPZ accounts for only 23%of the total area,but the contribution rate of water conservation reaches 80%.The actual values of water conservation and average water yield per unit pixel in the EFPZ show an increasing trend both internally and externally,while the counterfactual simulation values exhibit a decreasing trend.(3)The water conservation is much higher within the EFPZ than without EFPZ.The implementation of EFPZ has a significant effect on the improvement of the water conservation capacity in Maqu EFPZ and Yellow River Source EFPZ.The protection effectiveness should be enhanced in Qilian Mountain EFPZ and afforestation activities need to be carefully considered in Loess Plateau EFPZ. 展开更多
关键词 Water conservation function Ecological Function Protection Zone Counterfactual simulation Geo SOS-FLUS model InVEST model
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Monte Carlo Simulation-based Decision-making Model for the Water Conservation and Intermediate Water Recycling of Conservationminded Buildings
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作者 侯玲 《Journal of Landscape Research》 2012年第5期13-16,共4页
Through analyzing the life cycle cost of the water conservation and intermediate water application project of conservation-minded buildings,net present value(NPV) was applied as the index to establish the life cycle e... Through analyzing the life cycle cost of the water conservation and intermediate water application project of conservation-minded buildings,net present value(NPV) was applied as the index to establish the life cycle economic decision-making model.Monte Carlo simulation was used in demonstration cases,modeling analysis of water-saving projects in conservation-minded and traditional buildings verified rationality and practicability of this model and simulation method.It was to provide a referential and operable method for the decision-making of conservation-minded construction projects,as well as a scientific approach and theoretic basis for the precise decision-making of government organs,decision-making departments and developers. 展开更多
关键词 MONTE Carlo simulation conservation-minded building WATER conservation and INTERMEDIATE WATER RECYCLING ECONOMIC model
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Influence of varied drought types on soil conservation service within the framework of climate change:insights from the Jinghe River Basin,China
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作者 BAI Jizhou LI Jing +4 位作者 RAN Hui ZHOU Zixiang DANG Hui ZHANG Cheng YU Yuyang 《Journal of Arid Land》 SCIE CSCD 2024年第2期220-245,共26页
Severe soil erosion and drought are the two main factors affecting the ecological security of the Loess Plateau,China.Investigating the influence of drought on soil conservation service is of great importance to regio... Severe soil erosion and drought are the two main factors affecting the ecological security of the Loess Plateau,China.Investigating the influence of drought on soil conservation service is of great importance to regional environmental protection and sustainable development.However,there is little research on the coupling relationship between them.In this study,focusing on the Jinghe River Basin,China as a case study,we conducted a quantitative evaluation on meteorological,hydrological,and agricultural droughts(represented by the Standardized Precipitation Index(SPI),Standardized Runoff Index(SRI),and Standardized Soil Moisture Index(SSMI),respectively)using the Variable Infiltration Capacity(VIC)model,and quantified the soil conservation service using the Revised Universal Soil Loss Equation(RUSLE)in the historical period(2000-2019)and future period(2026-2060)under two Representative Concentration Pathways(RCPs)(RCP4.5 and RCP8.5).We further examined the influence of the three types of drought on soil conservation service at annual and seasonal scales.The NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP)dataset was used to predict and model the hydrometeorological elements in the future period under the RCP4.5 and RCP8.5 scenarios.The results showed that in the historical period,annual-scale meteorological drought exhibited the highest intensity,while seasonal-scale drought was generally weakest in autumn and most severe in summer.Drought intensity of all three types of drought will increase over the next 40 years,with a greater increase under the RCP4.5 scenario than under the RCP8.5 scenario.Furthermore,the intra-annual variation in the drought intensity of the three types of drought becomes smaller under the two future scenarios relative to the historical period(2000-2019).Soil conservation service exhibits a distribution pattern characterized by high levels in the southwest and southeast and lower levels in the north,and this pattern has remained consistent both in the historical and future periods.Over the past 20 years,the intra-annual variation indicated peak soil conservation service in summer and lowest level in winter;the total soil conservation of the Jinghe River Basin displayed an upward trend,with the total soil conservation in 2019 being 1.14 times higher than that in 2000.The most substantial impact on soil conservation service arises from annual-scale meteorological drought,which remains consistent both in the historical and future periods.Additionally,at the seasonal scale,meteorological drought exerts the highest influence on soil conservation service in winter and autumn,particularly under the RCP4.5 and RCP8.5 scenarios.Compared to the historical period,the soil conservation service in the Jinghe River Basin will be significantly more affected by drought in the future period in terms of both the affected area and the magnitude of impact.This study conducted beneficial attempts to evaluate and predict the dynamic characteristics of watershed drought and soil conservation service,as well as the response of soil conservation service to different types of drought.Clarifying the interrelationship between the two is the foundation for achieving sustainable development in a relatively arid and severely eroded area such as the Jinghe River Basin. 展开更多
关键词 meteorological drought hydrological drought agricultural drought soil conservation service Variable Infiltration Capacity(VIC)model Revised Universal Soil Loss Equation(RUSLE) Jinghe River Basin
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The Development of a Physical Conservation Fidelity Global Spectral Model-From Dynamic Framework to a Full Model 被引量:1
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作者 ZHONG Qi ZHONG Qing 《Atmospheric and Oceanic Science Letters》 2008年第1期33-35,共3页
The fidelity scheme of physical conservation laws has been applied in the dynamic framework of a global spectral model. In this study, a set of diabatic physical processes are also involved. Based on six 30-day numeri... The fidelity scheme of physical conservation laws has been applied in the dynamic framework of a global spectral model. In this study, a set of diabatic physical processes are also involved. Based on six 30-day numerical integrations of real-time data, we show that the full model is able to reproduce the primary features of global energy cycle and hydrological distribution. Additionally, the root-mean-square error is dramatically decreased when diabatic processes are considered. Another advantage is that the false structure of "double Intertropical Convergence Zone (ITCZ)" is not seen in the result, although the orecioitation rate becomes lower. 展开更多
关键词 fidelity of physical conservation laws spec-tral model energy cycle systematic error
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Integrating water use systems and soil and water conservation measures into a hydrological model of an Iranian Wadi system 被引量:1
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作者 Nariman MAHMOODI Jens KIESEL +1 位作者 Paul D WAGNER Nicola FOHRER 《Journal of Arid Land》 SCIE CSCD 2020年第4期545-560,共16页
Water resources are precious in arid and semi-arid areas such as the Wadis of Iran. To sustainably manage these limited water resources, the residents of the Iranian Wadis have been traditionally using several water u... Water resources are precious in arid and semi-arid areas such as the Wadis of Iran. To sustainably manage these limited water resources, the residents of the Iranian Wadis have been traditionally using several water use systems(WUSs) which affect natural hydrological processes. In this study, WUSs and soil and water conservation measures(SWCMs) were integrated in a hydrological model of the Halilrood Basin in Iran. The Soil and Water Assessment Tool(SWAT) model was used to simulate the hydrological processes between 1993 and 2009 at daily time scale. To assess the importance of WUSs and SWCMs, we compared a model setup without WUSs and SWCMs(Default model) with a model setup with WUSs and SWCMs(WUS-SWCM model). When compared to the observed daily stream flow, the number of acceptable calibration runs as defined by the performance thresholds(Nash-Sutcliffe efficiency(NSE)≥0.68, –25%≤percent bias(PBIAS)≤25% and ratio of standard deviation(RSR)≤0.56) is 177 for the Default model and 1945 for the WUS-SWCM model. Also, the average Kling–Gupta efficiency(KGE) of acceptable calibration runs for the WUS-SWCM model is higher in both calibration and validation periods. When WUSs and SWCMs are implemented, surface runoff(between 30% and 99%) and water yield(between 0 and 18%) decreased in all sub-basins. Moreover, SWCMs lead to a higher contribution of groundwater flow to the channel and compensate for the extracted water by WUSs from the shallow aquifer. In summary, implementing WUSs and SWCMs in the SWAT model enhances model plausibility significantly. 展开更多
关键词 SWAT model stream flow Wadis multi-metric framework water use systems soil and water conservation measures Halilrood Basin
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Spatiotemporal evolution of water conservation function and its driving factors in the Huangshui River Basin, China
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作者 YUAN Ximin SU Zhiwei +1 位作者 TIAN Fuchang WANG Pengquan 《Journal of Arid Land》 SCIE CSCD 2024年第11期1484-1504,共21页
The Grain for Green project has had a substantial influence on water conservation in the Huangshui River Basin,China through afforestation and grassland restoration over the past two decades.However,a comprehensive un... The Grain for Green project has had a substantial influence on water conservation in the Huangshui River Basin,China through afforestation and grassland restoration over the past two decades.However,a comprehensive understanding of the spatiotemporal evolution of water conservation function and its driving factors remains incomplete in this basin.In this study,we utilized the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model to examine the spatiotemporal evolution of water conservation function in the Huangshui River Basin from 2000 to 2020.Additionally,we employed the random forest model,Pearson correlation analysis,and geographical detector(Geodetector)techniques to investigate the primary factors and factor interactions affecting the spatial differentiation of water conservation function.The findings revealed several key points.First,the high-latitude northern region of the study area experienced a significant increase in water conservation over the 21-a period.Second,the Grain for Green project has played a substantial role in improving water conservation function.Third,precipitation,plant available water content(PAWC),grassland,gross domestic product(GDP),and forest land were primary factors influencing the water conservation function.Finally,the spatial differentiation of water conservation function was determined by the interactions among geographical conditions,climatic factors,vegetation biophysical factors,and socio-economic factors.The findings have significant implications for advancing ecological protection and restoration initiatives,enhancing regional water supply capabilities,and safeguarding ecosystem health and stability in the Huangshui River Basin. 展开更多
关键词 water conservation function Grain for Green project climate change Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model random forest geographical detector(Geodetector) Huangshui River Basin
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Palm Oil Production in Malaysia: An Analytical Systems Model for Balancing Economic Prosperity, Forest Conservation and Social Welfare 被引量:1
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作者 Nickson E. Otieno Xeuping Dai +4 位作者 Daniele De Barba Abbassi Bahman Elise Smedbol Marouan Rajeb Lise Jaton 《Agricultural Sciences》 2016年第2期55-69,共15页
Since the late 1950’s, the Malaysian human population has nearly quadrupled, increasing pressure on natural resource exploitation to meet domestic needs and to earn foreign exchange from exports. Global demand for Ma... Since the late 1950’s, the Malaysian human population has nearly quadrupled, increasing pressure on natural resource exploitation to meet domestic needs and to earn foreign exchange from exports. Global demand for Malaysian palm oil in particular had steeply increased since the mid-1970s and by 2013, the commodity was the leading foreign exchange earner. To fulfill and sustain this demand, the country’s economy has steadily shifted bias towards production and associated value addition of palm oil products for export. However, as a consequence, many of Malaysia’s natural tropical forests have been converted to palm oil farming resulting in loss of approximately 10,000 km2 of forest cover over the past twenty-five years, and biodiversity has been displaced or lost. To provide a deeper insight into the interplay amongst key interrelated environmental and socio-economic variables, and a forecast of possible future balance, we used a systems dynamism modeling tool, STELLAR (structural thinking, experiential learning laboratory with animation), to simulate and project how Malaysia could achieve a medium-term sustainable balance or optimization between palm oil production and forest conservation without compromising on human social welfare. The model consisted of four main modules (environmental, economic, social development and human welfare) each with component parameters, and interconnected by input and output loops. Model calibrations, testing and preruns involved existing official 30-year time-series datasets. Subsequently, four scenarios: Environmental conservation;Economic growth under increased global palm oil demand;Economy decline under decreased palm oil demand;and Control condition with little or no change, were selected for simulated projections of future possibilities. Simulation results showed that scenarios and variable interactions that reduce environmental damage would offer the best chance for optimizing the palm oil economy while also minimizing forest loss and promoting citizen social welfare. 展开更多
关键词 Palm Oil Systems modeling Sustainable Development conservation MALAYSIA
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Evaluation of the water conservation function in the Ili River Delta of Central Asia based on the InVEST model 被引量:2
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作者 CAO Yijie MA Yonggang +2 位作者 BAO Anming CHANG Cun LIU Tie 《Journal of Arid Land》 SCIE CSCD 2023年第12期1455-1473,共19页
The Ili River Delta(IRD)is an ecological security barrier for the Lake Balkhash and an important water conservation area in Central Asia.In this study,we selected the IRD as a typical research area,and simulated the w... The Ili River Delta(IRD)is an ecological security barrier for the Lake Balkhash and an important water conservation area in Central Asia.In this study,we selected the IRD as a typical research area,and simulated the water yield and water conservation from 1975 to 2020 using the water yield module of the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model.We further analyzed the temporal and spatial variations in the water yield and water conservation in the IRD from 1975 to 2020,and investigated the main driving factors(precipitation,potential evapotranspiration,land use/land cover change,and inflow from the Ili River)of the water conservation variation based on the linear regression,piecewise linear regression,and Pearson's correlation coefficient analyses.The results indicated that from 1975 to 2020,the water yield and water conservation in the IRD showed a decreasing trend,and the spatial distribution pattern was"high in the east and low in the west";overall,the water conservation of all land use types decreased slightly.The water conservation volume of grassland was the most reduced,although the area of grassland increased owing to the increased inflow from the Ili River.At the same time,the increased inflow has led to the expansion of wetland areas,the improvement of vegetation growth,and the increase of regional evapotranspiration,thus resulting in an overall reduction in the water conservation.The water conservation depth and precipitation had similar spatial distribution patterns;the change in climate factors was the main reason for the decline in the water conservation function in the delta.The reservoir in the upper reaches of the IRD regulated runoff into the Lake Balkhash,promoted vegetation restoration,and had a positive effect on the water conservation;however,this positive effect cannot offset the negative effect of enhanced evapotranspiration.These results provide a reference for the rational allocation of water resources and ecosystem protection in the IRD. 展开更多
关键词 water conservation function water yield Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model climate change land use/land cover change(LUCC) Ili River Delta Lake Balkhash
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Short-term deformation behavior model of endangered earthen heritage slope after conservation in Jiaohe Ruins
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作者 张景科 谌文武 和法国 《Journal of Central South University》 SCIE EI CAS 2012年第7期2029-2036,共8页
Cliff deformation behavior after conservation is of great significance for evaluating the conservation effect and discovering the dynamical law of soil. Modeling on deformation behavior is beneficial to the quantitati... Cliff deformation behavior after conservation is of great significance for evaluating the conservation effect and discovering the dynamical law of soil. Modeling on deformation behavior is beneficial to the quantitative evaluation of interactions between soil mass and structures as well as the forecast. Based on cliff conservation engineering of Jiaohe Ruins (the largest raw soil heritage site in the world), data of horizontal deformation of the upper cliff were obtained by using Nanrui-made NDW-50 displacement device (precision: 0.01 mm, frequency: 15 min^-l). Regression analysis indicates that deformation behavior models include exponential growth, linear growth and parabolic growth types, while daily deformation presents more intense periodicity (24 h). The deformation is less than 1.5 mm during monitoring period, which has no impact on the stability of cliff. Deformation behavior provides the mutual duress and interaction between soil and engineering intervention. In addition, deformation mode attaches tensely to the damage pattern of the cliff. The conclusions are of importance to the stability evaluation of the carrier along Silk Road. 展开更多
关键词 endangered cliff conservation deformation behavior regression analysis modelling
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Evaluating the Conservation Efforts of Multi-Projects Using Remote Sensing and Light Use Efficiency Model: A Case of Nyungwe Forest National Park, Rwanda
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作者 Evariste Rutebuka Lixiao Zhang +2 位作者 Ernest Frimpong Asamoah Emmanuel Rukundo Apollinaire William 《Open Journal of Forestry》 2018年第1期68-86,共19页
This paper investigates the effectiveness of conservation efforts in the Nyungwe Forest National Park (Nyungwe). The forest is one of the six key landscapes identified for conservation in the Albertine Rift because it... This paper investigates the effectiveness of conservation efforts in the Nyungwe Forest National Park (Nyungwe). The forest is one of the six key landscapes identified for conservation in the Albertine Rift because it hosts many threatened species. As such, a number of different stakeholders have been involved in its conservation since 1987;yet, studies that emphasize and evaluate the success of these conservation efforts are limited. We combined a rapid and relatively low cost remotely-sensed data and the Light Use Efficiency model to generate forest conservation indicators such as NDVI, forest canopy Net Primary Productivity and carbon sequestered from 1986 to 2010. The influence of topographic and climatic factors on these indicators was examined. The supervised classifier was used to catalogue the area into Forest, Wetland, and Bareland. The forest was the major category (above 90%) of Nyungwe relative to wetland and bareland. Based on degradation intensity, two distinctive periods were realised;the first period spans 8 years (1986-1994) whereas the second spans 16 years (1994-2010). The former degradation intensity period is 10 times higher than the latter period. Although the size of forest recovered up to 90%, the daily NPP and carbon sequestration capacity decreased by 37.1% (i.e. NPP 6.5 Mg tons in 1986 to 4.1 Mg tons in 2010). Areas of the forest that are physically constrained (high altitude) had a higher degradation. Guided by our indicators, there is an overall success in conservation efforts, but efforts were mostly concentrated in accessible areas. Therefore, conservation efforts that aim to respond to degradation of the inaccessible areas of the forest should be stressed in the management plan of the park. 展开更多
关键词 conservation EFFORTS FOREST CANOPY COVER Light Use Efficiency model Remote Sensing Nyungwe Rwanda
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Impact of regional human capital and urban sprawl on forest——based on a forest conservation model
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作者 Liu Na Zhao Shi +1 位作者 Shao Quan Feng Kai 《High Technology Letters》 EI CAS 2019年第2期207-215,共9页
Metropolitan cities in China have become a major economic hubs with an unprecedented increase of land use and decline of environmental resources. Based on a simple and abstract forest conservation model, this paper at... Metropolitan cities in China have become a major economic hubs with an unprecedented increase of land use and decline of environmental resources. Based on a simple and abstract forest conservation model, this paper attempts to explain changes of forest resources caused by urban sprawl. Through the research, it is found that high level of regional human capital is beneficial to curb urban sprawl. In this vein the model presents the urban forest conservation cost strategy at the Nash equilibrium of varied discount factor and parameter control. 展开更多
关键词 regional human capital urban sprawl Nash equilibrium forest conservation model cross-sectional econometric model
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On the energy conservation and critical velocities for the propagation of a "steady-shock" wave in a bar made of cellular material 被引量:8
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作者 Li-Li Wang Li-Ming Yang Yuan-Yuan Ding 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第3期420-428,共9页
The propagation of shock waves in a cellular bar is systematically studied in the framework of continuum solids by adopting two idealized material models, viz. the dynamic rigid, perfectly plastic, locking (D-R-PP-L... The propagation of shock waves in a cellular bar is systematically studied in the framework of continuum solids by adopting two idealized material models, viz. the dynamic rigid, perfectly plastic, locking (D-R-PP-L) model and the dynamic rigid, linear hardening plastic, locking (D-R-LHP-L) model, both considering the effects of strain-rate on the material properties. The shock wave speed relevant to these two models is derived. Consider the case of a bar made of one of such material with initial length L 0 and initial velocity v i impinging onto a rigid target. The variations of the stress, strain, particle velocity, specific internal energy across the shock wave and the cease distance of shock wave are all determined analytically. In particular the "energy conservation condition" and the "kinematic existence condition" as proposed by Tan et al. (2005) is re-examined, showing that the "energy conservation condition" and the consequent "critical velocity", i.e. the shock can only be generated and sustained in R-PP-L bars when the impact velocity is above this critical velocity, is incorrect. Instead, with elastic deformation, strain-hardening and strain-rate sensitivity of the cellular materials being considered, it is appropriate to redefine a first and a second critical impact velocity for the existence and propagation of shock waves in cellular solids. Starting from the basic relations for shock wave propagating in D-R-LHP-L cellular materials, a new method for inversely determining the dynamic stress-strain curve for cellular materials is proposed. By using e.g. a combination of Taylor bar and Hopkinson pressure bar impact experimental technique, the dynamic stress-strain curve of aluminum foam could bedetermined. Finally, it is demonstrated that this new formulation of shock theory in this one-dimensional stress state can be generalized to shocks in a one-dimensional strain state, i.e. for the case of plate impact on cellular materials, by simply making proper replacements of the elastic and plastic constants. 展开更多
关键词 Cellular solids 1D shock theory D-R-PP-L model D-R-SHP-L model Energy conservation across shock Critical velocities
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Estimation of conservation value of myrtle(Myrtus communis)using a contingent valuation method:a case study in a Dooreh forest area,Lorestan Province,Iran 被引量:3
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作者 Neda Amiri Seyed F.Emadian +2 位作者 Asghar Fallah Kamran Adeli Hamid Amirnejad 《Forest Ecosystems》 SCIE CSCD 2016年第1期26-36,共11页
Background: Around 2000 plant species occur naturally in Lorestan Province of which 250 species are medicinal and myrtle is one of them. Myrtle is a shrub whose leaves and fruits have medicinal value and thus, if man... Background: Around 2000 plant species occur naturally in Lorestan Province of which 250 species are medicinal and myrtle is one of them. Myrtle is a shrub whose leaves and fruits have medicinal value and thus, if managed and harvested properly, could produce sustained economic benefits. In recent years, however, over half of the myrtle site areas was destroyed, due to inappropriate management and excessive harvesting practices. Thus, coming up with a practical harvesting approach along with identifying those factors damaging the sites, seems to be very crucial. Methods: In our investigation, we calculated the conservation value per hectare of myrtle in the Dooreh forest area in Lorestan Province. Using the Contingent Valuation (CV) and Double Bounded Dichotomous Choice (DBDC) methods, we determined the willingness to pay (VVTP) for myrtle conservation. The VVTP was estimated with a Iogit model for which indices were obtained based on a maximum precision criterion. Results: The results showed that 86.67 per cent of people were willing to pay for the conservation of these myrtle sites. Average monthly WTP per family was calculated as $0.79. The annual conservation value in terms of WTP for the preservation of the myrtle sites in Dooreh was estimated as $102,525. Among the variables of the model presented, education had a positive impact, while the amount proposed for payment and family size had a negative impact on the WTP. Conclusions: Our estimate of the value of myrtle conservation should provide justification for policy makers and decision making bodies of natural resources to implement policies in order to conserve the natural sites of this species more effectively. 展开更多
关键词 conservation value Myrtle Contingent valuation method Double Bounded Dichotomous method Logit model
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Interrelations Between Socio-economic Development and Environmental Quality:a Simulation Integrating System Dynamics Models with GIS 被引量:3
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作者 YU Jie BIAN Fuling +1 位作者 PETERSON Jim LI Pingxiang 《Geo-Spatial Information Science》 2005年第3期176-182,共7页
System dynamics (SD) theory has long been deployed in modeling complex non-linear interrelationships but, so far it has not been common to do the kind of modeling in support of bringing environmental sustainability po... System dynamics (SD) theory has long been deployed in modeling complex non-linear interrelationships but, so far it has not been common to do the kind of modeling in support of bringing environmental sustainability policies to practice. This is largely because the challenge of including spatial data has not yet been well met. Potential for adoption of SD and GIS methods in combination is exemplified with the results of a decision-support exercise designed for simulation and prediction of the dynamic inter-relationships between socio-economic development and environmental quality for the "Wen, Pi, Du" county in Sichuan province, southwestern China. 展开更多
关键词 system dynamics GIS dynamic simulation eco-economic system SD model analytic hierarchy process
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Population Viability Analysis of Gloydius shedaoensis from Northeastern China:A Contribution to the Assessment of the Conservation and Management Status of an Endangered Species 被引量:2
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作者 LIU Peng SUN Lixin +3 位作者 LI Jianli WANG Li ZHAO Wenge JIA Jingbo 《Asian Herpetological Research》 SCIE 2010年第1期48-56,共9页
Shedao pit-vipers(Gloydius shedaoensis) on Snake Island in the Liaoning Province, China, are among the most imperiled species in China. The isolated and unique populations are crucial in the recovery of this endangere... Shedao pit-vipers(Gloydius shedaoensis) on Snake Island in the Liaoning Province, China, are among the most imperiled species in China. The isolated and unique populations are crucial in the recovery of this endangered species by providing a way for conservation and management. Research based on the ecological simulation tools can evaluate alternative mitigation strategies in terms of their benefits to the populations, which are vital for informed decision-making. In this paper, using the program VORTEX 9.42, we developed a population viability analysis(PVA) for the Shedao pit-viper to:(1) address the extinction likelihood of the population;(2) simulate population dynamics under various environment events, and(3) evaluate the efficacy of current protection and management strategies. Overall, we found the population to be susceptible to the factors of catastrophic events, mortality and environment capacity. The population is recovering slowly at present on account of improvement of habitat and greater food availability. Under the current conditions, the probability of extinction in 100 years is approximately zero. These data coincide with the evidence that the wild population may be arriving at K. Our results strengthen the view that protection and management can create a pronounced effect on populations of this endangered species. 展开更多
关键词 Gloydius shedaoensis VORTEX simulation model sensitivity analysis model veracity test species conservation
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θ-improved limited tolerance relation model of incomplete information system for evaluation of water conservancy project management modernization 被引量:4
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作者 Yu-qin GAO Guo-hua FANG Ya-qin LIU 《Water Science and Engineering》 EI CAS CSCD 2013年第4期469-477,共9页
The modernization of water conservancy project management is a complicated engineering system involving a management system, a management method, management personnel, the exertion of social, economic, and ecological ... The modernization of water conservancy project management is a complicated engineering system involving a management system, a management method, management personnel, the exertion of social, economic, and ecological effects, and so on. However, indices for evaluating the modernization of water conservancy project management are usually unobtainable in practical applications. Conducting appropriate extension of the classical rough set theory and then applying it to an incomplete information system are the key to the application of the rough set theory Based on analysis of some extended rough set models in incomplete information systems, a rough set model based on the θ-improved limited tolerance relation is put forward. At the same time, upper approximation and lower approximation are defined under this improved relation. According to the evaluation index system and management practices, the threshold for θ is defined. An example study indicates the practicability and maneuverability of the model. 展开更多
关键词 Key words: modernization of water conservancy project management O-improved limitedtolerance relation model upper and lower approximations threshold
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Fractional Birkhoffian Dynamics Based on Quasi-fractional Dynamics Models and Its Lie Symmetry 被引量:3
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作者 JIA Yundie ZHANG Yi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第1期84-95,共12页
In order to investigate the dynamic behavior of non-conservative systems,the Lie symmetries and conserved quantities of fractional Birkhoffian dynamics based on quasi-fractional dynamics model are proposed and studied... In order to investigate the dynamic behavior of non-conservative systems,the Lie symmetries and conserved quantities of fractional Birkhoffian dynamics based on quasi-fractional dynamics model are proposed and studied.The quasi-fractional dynamics model here refers to the variational problem based on the definition of RiemannLiouville fractional integral(RLFI),the variational problem based on the definition of extended exponentially fractional integral(EEFI),and the variational problem based on the definition of fractional integral extended by periodic laws(FIEPL).First,the fractional Pfaff-Birkhoff principles based on quasi-fractional dynamics models are established,and the corresponding Birkhoff’s equations and the determining equations of Lie symmetry are obtained.Second,for fractional Birkhoffian systems based on quasi-fractional models,the conditions and forms of conserved quantities are given,and Lie symmetry theorems are proved.The Pfaff-Birkhoff principles,Birkhoff’s equations and Lie symmetry theorems of quasi-fractional Birkhoffian systems and classical Birkhoffian systems are special cases of this article.Finally,some examples are given. 展开更多
关键词 quasi-fractional dynamics model Lie symmetry conserved quantity fractional Birkhoffian system Riemann-Liouville derivative
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