The goal of this study is to assess the ability of existing car washing stations in Khartoum City using an ArcMap suitability modeling tool. Methods: In Khartoum, an increasing number of vehicle wash stations were ope...The goal of this study is to assess the ability of existing car washing stations in Khartoum City using an ArcMap suitability modeling tool. Methods: In Khartoum, an increasing number of vehicle wash stations were opened every day. The main criteria are street, the slope, the hospitals, the police station, and the school, which have been used to build a model of suitability based on weight overlay in ArcGIS 10.4. The findings revealed two evaluation tendencies. One tendency involves business centers that are located on main roads but are adjacent to residential areas, while another involves business centers that have rezoned residential plots without consideration for ideal site requirements for the environment. There are locations that would be appropriate for vehicle wash centers, according to the final suitability map. On a scale of 1 to 5, less than 30% of the study area is considered suitable for a new car wash regarding class 5. On the other hand, significant areas are available for car wash development in the second value of suitability 4, but as second-ranked suitability. The assessment was accomplished by comparing the final suitability map of car washing centers to the layers which represented them.展开更多
The quality of environmental data and its possible impact on the marine species habitat modelling are often overlooked while the sources for these data are increasing.This study selected sea surface temperature(SST)fr...The quality of environmental data and its possible impact on the marine species habitat modelling are often overlooked while the sources for these data are increasing.This study selected sea surface temperature(SST)from two commonly used sources,the NOAA Ocean Watch and IRI/LDEO Climate Data Library,and then constructed habitat suitability index model to evaluate the influences of SST from the two sources on the outcomes of Ommastrephes bartramii habitat models for the months of July–October in the Northwest Pacific Ocean during 1996–2012.This study examined the differences in the amount of estimated unfavourable/favourable habitat area when the SST used for model building and inference were the same or different.Dynamics in suitable habitat area calculated from SST was insensitive to the two different SST products.In the fishing season of O.bartramii,the changes of magnitude and trend of monthly suitable habitat area in August and September were similar over time,whereas there were large differences for July and October.Importantly,there is a substantial lack of consistency in the O.bartramii habitat distribution based on SST of two sources.This study considered the sources of environmental data for habitat modelling and then inferred species habitat distribution whether by the same or different data source.展开更多
Finding the right balance between timber production and the management of forest-dependent wildlife species,present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan.A possible expl...Finding the right balance between timber production and the management of forest-dependent wildlife species,present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan.A possible explanation of this can be found in the unique nature of the forest management area which is populated with various kinds of rare and endangered species.This issue has been brought to light as a result of the nomination of northern Okinawa Island in 2018 as a candidate for World Natural Heritage site.The nomination has raised public awareness to the possibility of conflicting management objectives between timber extraction and the conservation of habitat for forest-dependent wildlife species.Managing exclusively for one objective over the other may fail to meet the demand for both forest products and wildlife habitat,ultimately jeopardizing the stability of human and wildlife communities.It is therefore important to achieve a better balance between the objective of timber production and conservation of wildlife habitat.Despite the significance of this subject area,current ongoing discussions on how to effectively manage for forest resources,often lack scientific basis to make sound judgement or evaluate tradeoffs between conflicting objectives.Quantifying the effect of these forest management activities on wildlife habitat provides useful and important information needed to make forest management and policy decisions.In this study we develop a spatial timber harvest scheduling model that incorporates habitat suitability index(HSI)models for the Okinawa Rail(Gallirallus okinawae),an endangered avian species found on Okinawa,Japan.To illustrate how the proposed coupling model assembles spatial information,which ultimately aids the study of forest management effects on wildlife habitat,we apply these models to a forest area in Okinawa and conduct a simple simulation analysis.展开更多
In this paper,based on the finite volume method,a high-precision hydrodynamic model coupled with the habitat suitability model is established,and the computational efficiency of the coupled model is improved by a grap...In this paper,based on the finite volume method,a high-precision hydrodynamic model coupled with the habitat suitability model is established,and the computational efficiency of the coupled model is improved by a graphics processing unit(GPU)-accelerated technology.The coupled model is used to solve the problem of the non-conservation of mass that may be caused by the nearshore hydrodynamic model in the processing of wetting and drying,while avoiding the unphysical high velocities at the wetting and drying boundaries.The coupled model is applied to simulate the high-precision hydrodynamic process of the Liao River estuary(LRE)and the hydrological habitat suitability of the estuarine vegetation(Suaeda heteroptera)growing in the LRE.The simulated values of the hydrological variables(the water level,the water depth,the current velocity and direction)are highly consistent with the measured values.The root mean square errors(RMSE)of the hydrological variables are 0.10m,0.12m/s and 17.24°,respectively.Furthermore,the simulated combined suitability index(CSI)distribution of Suaeda heteroptera(S.heteroptera)matches with the distribution of S.heteroptera obtained from the high-resolution remote sensing satellite images during the same time period.The ratio of the simulated weighted usable area(WUA)of S.heteroptera to the area obtained from the remote sensing satellite images during the same period is 81.9%.This study reveals the phenomenon that the distribution of S.heteroptera in the LRE is highly correlated with the high-precision hydrodynamic processes,and provides a scientific basis and a valuable reference for the conservation and the restoration of the estuarine vegetation.展开更多
The COVID-19 outbreak that became a global pandemic in early 2020 is starting to affect agricultural supply chains and leading to a rapid rise in global food prices.As many grain exporting countries announced a ban on...The COVID-19 outbreak that became a global pandemic in early 2020 is starting to affect agricultural supply chains and leading to a rapid rise in global food prices.As many grain exporting countries announced a ban on grain exports,food security issues in China have attracted a significant international attention.Based on the Suitability Distribution Model and Soybean-Cereal Constraint Model,we explored the relationship between soybean production potential and food security.We calculated that the soybean potential planting area in China is 164.3 million ha.If the outbreak prevents China from importing soybeans,soybean planting area will need to be increased by 6.9 times to satisfy the demands.In the meantime,cereal self-sufficiency rate will drop to 63.4%,which will greatly affect food security.Each additional unit of soybean production will reduce 3.9 units of cereal production,and 1%increase in the self-sufficiency rate of soybean will result in a 0.63%drop in the self-sufficiency rate of cereal.Without sacrificing the self-sufficiency rate of cereal,the self-sufficiency rate of soybean is limited to 42%.Consequently,China will still need to import more than 68%of the current import volume of soybean.Although in the short term,the outbreak will not affect food security in China,as soybean imports decrease,insufficient supply of soybeans will affect people’s quality of life.To prevent the impact of the COVID-19 outbreak,China should increase soybean stocks and strengthen international cooperation.In the long term,increasing the self-sufficiency rate is a fundamental solution to solving soybean import dependency.The key to increasing soybean cultivation is by making soybean cultivation profitable and by building a sustainable soybean planting chain.展开更多
Visual satisfaction of the tourists with a water body is strongly influenced by water clarity, which is in turn influenced by a number of water quality parameters. Visual satisfaction thus stands to benefit from havin...Visual satisfaction of the tourists with a water body is strongly influenced by water clarity, which is in turn influenced by a number of water quality parameters. Visual satisfaction thus stands to benefit from having a water quality management tool that results in better water clarity. A Clarity Suitability Index of Water Quality (CSIWQ), derived from clarity suitability curves of selected water quality parameters, can allow estimation of optimal values for these parameters, while ensuring high visual satisfaction among tourists. The present study used sampling and survey methodologies to investigate water clarity and quality at five tourism fishing ports;simultaneously, tourists’ visual satisfaction with a water body was assessed through a questionnaire based on their perceptions. The relationship between tourists’ visual satisfaction and water clarity was found to be positive and strong, with water clarity having predictive power of 74.2%. The study showed that DO, BOD, TP, and SS were the most critical parameters for water clarity. A continued product approach of CSIWQ was found to be most appropriate for describing the relationship between water clarity and these four parameters. This enabled a CSIWQ Index value to be calculated. With a CSIWQ value of 0.6, water clarity would be more than 2.08 m, and tourists would experience very high satisfaction. CSI curves showed that DO would preferably be 9.0 mg/L, and BOD, TP, and SS less than 0.5 mg/L, 0.12 mg/L, and 45.0 mg/L, respectively. The model thus produced valuable insights for assessing and improving water quality and ensuring high levels of visual satisfaction among tourists in tourism fishing ports. This model identified only four parameters but could be improved by ensuring that other water quality parameters were included, to encourage an increase in the number of tourists and to include monitoring of more pollutant sources.展开更多
A three-dimensional cloud-scale model has been designed.The governing equations of the model are composed of two groups of equations:one group includes compressible motion equations,continuity equation, pressure equat...A three-dimensional cloud-scale model has been designed.The governing equations of the model are composed of two groups of equations:one group includes compressible motion equations,continuity equation, pressure equation and thermodynamic equation,which are of Eulerian type,and the other consists of cloud- precipitation microphysics equations which are of Lagrangian type.Since the degree of influence of sound wave on the air motion is quite different from that on the temperature or hydrometeors,the time splitting procedure is used in solving governing equations.Both unstaggered and staggered meshes have been utilized.Integra- tion schemes adopted are the Eulerian backward difference method for the unstaggered mesh and semi-implicit method for staggered mesh.Several experiments of modelling have been conducted and a reasonable three- dimensional image of deep convection is obtained.With this model the horizontal and vertical vortex circula- tions are simulated.Furthermore,the effects of horizontal vortex on the formation and development of downdraft within cloud have also been studied.展开更多
The objective of this study was to assess the biomass production potential from hybrid poplars using marginal lands in the state of Connecticut,USA.A land-use suitability model was developed to identify and classify m...The objective of this study was to assess the biomass production potential from hybrid poplars using marginal lands in the state of Connecticut,USA.A land-use suitability model was developed to identify and classify marginal lands in the state that could be used for growing hybrid poplars as a biofuel woody energy crop.The model was built on a geographic information system(GIS)platform,consisting of an exclusion area section,an ecological suitability section,and an economic/land-use suitability section.The model then was used to estimate the total biomass of the land-cover forests,annual biomass from forest and agricultural residues,and in particular the production potential of biomass from hybrid poplars over marginal lands in the state at county level.The results indicated that about 50%of the land in this state is unavailable for hybrid poplar cultivation and that less than 5%is highly suitable.The amount of usable area is highly variable on the county level.Without large-scale land use change,it appears that biofuel production in this state can only be a supplemental resource to the current energy supply.展开更多
Based on the citrus temperature, precipitation, sunlight and climate risk degree, the article divides subtropics of China into three types: the low risk region, the moderate risk region and the high risk region. The ...Based on the citrus temperature, precipitation, sunlight and climate risk degree, the article divides subtropics of China into three types: the low risk region, the moderate risk region and the high risk region. The citrus temperature risk increases with increasing latitude (except for the western mountainous area of subtropics of China). The citrus precipitation risk in the central part of subtropics of China is higher than that in the northern and western parts. The distributions of citrus sunlight risk are not consistent to those of the citrus precipitation risk. The citrus climate risk is mainly influenced by temperature. There is latitudinal zonal law for the distribution of the climate risk, that is, the climate risk increases with increasing latitude At the same time the climate risk in mountainous area is high and that in eastern plain area is low. There are differences in the temporal and spatial changes of the citrus climate. In recent 46 years, the citrus climate risk presents a gradual increasing trend in subtropics of China, especially it has been increasing fast since the 1980s. Because of the global warming, the low risk region in the eastern and southern parts has a gradual decreasing trend, however, the high risk region in the northern and western parts has an increasing trend and the high risk region has been extending eastward and southward. The article analyses the distribution of the citrus climate risk degree of reduction rates of 〉10%, 〉20% and 〉30% in subtropics of China, and studies their changes in different time periods. Results show that the risk is increasing from southeast to northwest.展开更多
文摘The goal of this study is to assess the ability of existing car washing stations in Khartoum City using an ArcMap suitability modeling tool. Methods: In Khartoum, an increasing number of vehicle wash stations were opened every day. The main criteria are street, the slope, the hospitals, the police station, and the school, which have been used to build a model of suitability based on weight overlay in ArcGIS 10.4. The findings revealed two evaluation tendencies. One tendency involves business centers that are located on main roads but are adjacent to residential areas, while another involves business centers that have rezoned residential plots without consideration for ideal site requirements for the environment. There are locations that would be appropriate for vehicle wash centers, according to the final suitability map. On a scale of 1 to 5, less than 30% of the study area is considered suitable for a new car wash regarding class 5. On the other hand, significant areas are available for car wash development in the second value of suitability 4, but as second-ranked suitability. The assessment was accomplished by comparing the final suitability map of car washing centers to the layers which represented them.
基金The National Key R&D Program of China under contract Nos 2019YFD0901401 and 2019YFD0901404the National Natural Science Foundation of China under contract No.NSFC41876141+1 种基金the Shanghai Science and Technology Innovation Program under contract No.19DZ1207502the Construction and Application of Natural Resources Satellite Remote Sensing Technology System under contract No.202101004。
文摘The quality of environmental data and its possible impact on the marine species habitat modelling are often overlooked while the sources for these data are increasing.This study selected sea surface temperature(SST)from two commonly used sources,the NOAA Ocean Watch and IRI/LDEO Climate Data Library,and then constructed habitat suitability index model to evaluate the influences of SST from the two sources on the outcomes of Ommastrephes bartramii habitat models for the months of July–October in the Northwest Pacific Ocean during 1996–2012.This study examined the differences in the amount of estimated unfavourable/favourable habitat area when the SST used for model building and inference were the same or different.Dynamics in suitable habitat area calculated from SST was insensitive to the two different SST products.In the fishing season of O.bartramii,the changes of magnitude and trend of monthly suitable habitat area in August and September were similar over time,whereas there were large differences for July and October.Importantly,there is a substantial lack of consistency in the O.bartramii habitat distribution based on SST of two sources.This study considered the sources of environmental data for habitat modelling and then inferred species habitat distribution whether by the same or different data source.
基金supported by a Grant-in-Aid for Scientific Researches (No. 16K12641&17H00806) from the Ministry of Education, Culture, Sports, Science, and technology of Japan
文摘Finding the right balance between timber production and the management of forest-dependent wildlife species,present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan.A possible explanation of this can be found in the unique nature of the forest management area which is populated with various kinds of rare and endangered species.This issue has been brought to light as a result of the nomination of northern Okinawa Island in 2018 as a candidate for World Natural Heritage site.The nomination has raised public awareness to the possibility of conflicting management objectives between timber extraction and the conservation of habitat for forest-dependent wildlife species.Managing exclusively for one objective over the other may fail to meet the demand for both forest products and wildlife habitat,ultimately jeopardizing the stability of human and wildlife communities.It is therefore important to achieve a better balance between the objective of timber production and conservation of wildlife habitat.Despite the significance of this subject area,current ongoing discussions on how to effectively manage for forest resources,often lack scientific basis to make sound judgement or evaluate tradeoffs between conflicting objectives.Quantifying the effect of these forest management activities on wildlife habitat provides useful and important information needed to make forest management and policy decisions.In this study we develop a spatial timber harvest scheduling model that incorporates habitat suitability index(HSI)models for the Okinawa Rail(Gallirallus okinawae),an endangered avian species found on Okinawa,Japan.To illustrate how the proposed coupling model assembles spatial information,which ultimately aids the study of forest management effects on wildlife habitat,we apply these models to a forest area in Okinawa and conduct a simple simulation analysis.
基金Project supported by the National Key Research and Development Program of China(Grant No.2019YFC1407700)the National Natural Science Foundation of China(Grant No.51779038).
文摘In this paper,based on the finite volume method,a high-precision hydrodynamic model coupled with the habitat suitability model is established,and the computational efficiency of the coupled model is improved by a graphics processing unit(GPU)-accelerated technology.The coupled model is used to solve the problem of the non-conservation of mass that may be caused by the nearshore hydrodynamic model in the processing of wetting and drying,while avoiding the unphysical high velocities at the wetting and drying boundaries.The coupled model is applied to simulate the high-precision hydrodynamic process of the Liao River estuary(LRE)and the hydrological habitat suitability of the estuarine vegetation(Suaeda heteroptera)growing in the LRE.The simulated values of the hydrological variables(the water level,the water depth,the current velocity and direction)are highly consistent with the measured values.The root mean square errors(RMSE)of the hydrological variables are 0.10m,0.12m/s and 17.24°,respectively.Furthermore,the simulated combined suitability index(CSI)distribution of Suaeda heteroptera(S.heteroptera)matches with the distribution of S.heteroptera obtained from the high-resolution remote sensing satellite images during the same time period.The ratio of the simulated weighted usable area(WUA)of S.heteroptera to the area obtained from the remote sensing satellite images during the same period is 81.9%.This study reveals the phenomenon that the distribution of S.heteroptera in the LRE is highly correlated with the high-precision hydrodynamic processes,and provides a scientific basis and a valuable reference for the conservation and the restoration of the estuarine vegetation.
基金supported by the National Natural Science Foundation of China(Grant No.41625001,31660233).
文摘The COVID-19 outbreak that became a global pandemic in early 2020 is starting to affect agricultural supply chains and leading to a rapid rise in global food prices.As many grain exporting countries announced a ban on grain exports,food security issues in China have attracted a significant international attention.Based on the Suitability Distribution Model and Soybean-Cereal Constraint Model,we explored the relationship between soybean production potential and food security.We calculated that the soybean potential planting area in China is 164.3 million ha.If the outbreak prevents China from importing soybeans,soybean planting area will need to be increased by 6.9 times to satisfy the demands.In the meantime,cereal self-sufficiency rate will drop to 63.4%,which will greatly affect food security.Each additional unit of soybean production will reduce 3.9 units of cereal production,and 1%increase in the self-sufficiency rate of soybean will result in a 0.63%drop in the self-sufficiency rate of cereal.Without sacrificing the self-sufficiency rate of cereal,the self-sufficiency rate of soybean is limited to 42%.Consequently,China will still need to import more than 68%of the current import volume of soybean.Although in the short term,the outbreak will not affect food security in China,as soybean imports decrease,insufficient supply of soybeans will affect people’s quality of life.To prevent the impact of the COVID-19 outbreak,China should increase soybean stocks and strengthen international cooperation.In the long term,increasing the self-sufficiency rate is a fundamental solution to solving soybean import dependency.The key to increasing soybean cultivation is by making soybean cultivation profitable and by building a sustainable soybean planting chain.
文摘Visual satisfaction of the tourists with a water body is strongly influenced by water clarity, which is in turn influenced by a number of water quality parameters. Visual satisfaction thus stands to benefit from having a water quality management tool that results in better water clarity. A Clarity Suitability Index of Water Quality (CSIWQ), derived from clarity suitability curves of selected water quality parameters, can allow estimation of optimal values for these parameters, while ensuring high visual satisfaction among tourists. The present study used sampling and survey methodologies to investigate water clarity and quality at five tourism fishing ports;simultaneously, tourists’ visual satisfaction with a water body was assessed through a questionnaire based on their perceptions. The relationship between tourists’ visual satisfaction and water clarity was found to be positive and strong, with water clarity having predictive power of 74.2%. The study showed that DO, BOD, TP, and SS were the most critical parameters for water clarity. A continued product approach of CSIWQ was found to be most appropriate for describing the relationship between water clarity and these four parameters. This enabled a CSIWQ Index value to be calculated. With a CSIWQ value of 0.6, water clarity would be more than 2.08 m, and tourists would experience very high satisfaction. CSI curves showed that DO would preferably be 9.0 mg/L, and BOD, TP, and SS less than 0.5 mg/L, 0.12 mg/L, and 45.0 mg/L, respectively. The model thus produced valuable insights for assessing and improving water quality and ensuring high levels of visual satisfaction among tourists in tourism fishing ports. This model identified only four parameters but could be improved by ensuring that other water quality parameters were included, to encourage an increase in the number of tourists and to include monitoring of more pollutant sources.
文摘A three-dimensional cloud-scale model has been designed.The governing equations of the model are composed of two groups of equations:one group includes compressible motion equations,continuity equation, pressure equation and thermodynamic equation,which are of Eulerian type,and the other consists of cloud- precipitation microphysics equations which are of Lagrangian type.Since the degree of influence of sound wave on the air motion is quite different from that on the temperature or hydrometeors,the time splitting procedure is used in solving governing equations.Both unstaggered and staggered meshes have been utilized.Integra- tion schemes adopted are the Eulerian backward difference method for the unstaggered mesh and semi-implicit method for staggered mesh.Several experiments of modelling have been conducted and a reasonable three- dimensional image of deep convection is obtained.With this model the horizontal and vertical vortex circula- tions are simulated.Furthermore,the effects of horizontal vortex on the formation and development of downdraft within cloud have also been studied.
文摘The objective of this study was to assess the biomass production potential from hybrid poplars using marginal lands in the state of Connecticut,USA.A land-use suitability model was developed to identify and classify marginal lands in the state that could be used for growing hybrid poplars as a biofuel woody energy crop.The model was built on a geographic information system(GIS)platform,consisting of an exclusion area section,an ecological suitability section,and an economic/land-use suitability section.The model then was used to estimate the total biomass of the land-cover forests,annual biomass from forest and agricultural residues,and in particular the production potential of biomass from hybrid poplars over marginal lands in the state at county level.The results indicated that about 50%of the land in this state is unavailable for hybrid poplar cultivation and that less than 5%is highly suitable.The amount of usable area is highly variable on the county level.Without large-scale land use change,it appears that biofuel production in this state can only be a supplemental resource to the current energy supply.
基金National Natural Sciences Foundation of China,No.40771033Special Item Funds of Climate Change Supported by China Meteorological Administration,No.CCSF-09-11
文摘Based on the citrus temperature, precipitation, sunlight and climate risk degree, the article divides subtropics of China into three types: the low risk region, the moderate risk region and the high risk region. The citrus temperature risk increases with increasing latitude (except for the western mountainous area of subtropics of China). The citrus precipitation risk in the central part of subtropics of China is higher than that in the northern and western parts. The distributions of citrus sunlight risk are not consistent to those of the citrus precipitation risk. The citrus climate risk is mainly influenced by temperature. There is latitudinal zonal law for the distribution of the climate risk, that is, the climate risk increases with increasing latitude At the same time the climate risk in mountainous area is high and that in eastern plain area is low. There are differences in the temporal and spatial changes of the citrus climate. In recent 46 years, the citrus climate risk presents a gradual increasing trend in subtropics of China, especially it has been increasing fast since the 1980s. Because of the global warming, the low risk region in the eastern and southern parts has a gradual decreasing trend, however, the high risk region in the northern and western parts has an increasing trend and the high risk region has been extending eastward and southward. The article analyses the distribution of the citrus climate risk degree of reduction rates of 〉10%, 〉20% and 〉30% in subtropics of China, and studies their changes in different time periods. Results show that the risk is increasing from southeast to northwest.