Timely investigating post-disaster situations to locate survivors and secure hazardous sources is critical,but also very challenging and risky.Despite first responders putting their lives at risk in saving others,huma...Timely investigating post-disaster situations to locate survivors and secure hazardous sources is critical,but also very challenging and risky.Despite first responders putting their lives at risk in saving others,human-physical limits cause delays in response time,resulting in fatality and property damage.In this paper,we proposed and implemented a framework intended for creating collaboration between heterogeneous unmanned vehicles and first responders to make search and rescue operations safer and faster.The framework consists of unmanned aerial vehicles(UAVs),unmanned ground vehicles(UGVs),a cloud-based remote control station(RCS).A light-weight message queuing telemetry transport(MQTT)based communication is adopted for facilitating collaboration between autonomous systems.To effectively work under unfavorable disaster conditions,antenna tracker is developed as a tool to extend network coverage to distant areas,and mobile charging points for the UAVs are also implemented.The proposed framework’s performance is evaluated in terms of end-to-end delay and analyzed using architectural analysis and design language(AADL).Experimental measurements and simulation results show that the adopted communication protocol performs more efficiently than other conventional communication protocols,and the implemented UAV control mechanisms are functioning properly.Several scenarios are implemented to validate the overall effectiveness of the proposed framework and demonstrate possible use cases.展开更多
The Three Gorges project accelerates economic development in the Three Gorges Reservoir Area.This paper aimed to investigate the distribution,changes and features of cultivated land in this area,analyze the forces dri...The Three Gorges project accelerates economic development in the Three Gorges Reservoir Area.This paper aimed to investigate the distribution,changes and features of cultivated land in this area,analyze the forces driving the changes in cultivated land area,and propose the countermeasures for cultivated land management.Transition matrix was used to analyze the features of cultivated land changes,and quantitative analysis and qualitative analysis were adopted to research the driving forces according to the features of cultivated land changes.Cultivated land in the Three Gorges Reservoir Area mainly lay to the northwest of the Yangtze River,especially the upper reaches.The areas of cultivated land increased from 1996 to 1999,then decreased from 2000 to 2006,and finally increased again from 2007 to 2009.The important forces driving changes in cultivated land included government policies,employment and food security,increasing construction land,agriculture structure adjustment,land rearrangement,inundation.During cultivated land management,firstly,it is necessary to insist on the principle of cultivated land protection,standardize land exploitation and strictly restrict the transformation of cultivated land into non-farming land.Secondly,land rearrangement must be implemented,which can not only increase the area of the cultivated land,but also improve the quality of the cultivated land.Thirdly,it is feasible to intensify eco-agriculture construction to increase the quantity and quality of cultivated land.Fourthly,it is helpful to improve the traditional agriculture production methods to promote cultivated land quality.Lastly,it is important to propagandize cultivated land protection and realize the enormous pressure of cultivated land shortage,making more people obligated to protect cultivated land.展开更多
Based on the Intranet technique,the design and implementation of rural area electricity Management Information System(RAEMIS)is researched.And then,a new RAEMIS with opening dynamic multimedia hypertext architecture i...Based on the Intranet technique,the design and implementation of rural area electricity Management Information System(RAEMIS)is researched.And then,a new RAEMIS with opening dynamic multimedia hypertext architecture is proposed.The advantages of new system include uniform user interface friendly,quick and accurate database accessing,and easy maintenance.展开更多
Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studie...Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studied. Fixed observation results from 1993to 2002 showed that pools covering about 15% of total area could store up 10% of surfacerunoff, keep 78.1% of eroded soil and 65.4% of lost nutrients. The yearly ratio ofinterception and evapotranspiration in land, storage in pools and drainage was 7:2:1,which ensured the resources and nutrients equilibrium and a benign recycle in thecatchment area system, and benefited the aquatic culture and helped to resist seasonaldrought. Moreover, the results showed that soil erosion modulus decreased significantly,equal to or lower than soil loss tolerance (≤500 tkm-2) in reddish yellow soil regions.Soil organic matter, total and available N content in sloping land, dryland and paddyfield increased steadily (>10%); water storage enhanced by more than 20% in sloping landand dryland in drought season; crop production increased by more than 20%; and productionof trees, fruits, tea and fish as well as land productivity increased yearly.展开更多
The management of sea area useplays an important role in safeguardingthe reasonable development and useof sea area resources and the healthyand orderly development of the marineeconomy.It is therefore a major componen...The management of sea area useplays an important role in safeguardingthe reasonable development and useof sea area resources and the healthyand orderly development of the marineeconomy.It is therefore a major componentof marine management.Thispaper outlines the construction of astandards system for sea area usemanagement,and looks at the system'sstructure,as well as the numberof standards and the scope of thestandards system.In addition,the paperelaborates on the important functionof the standards system in themanagement of sea area use,andproposes measures aimed at furtherimproving the management,formulation,implementation and revision ofstandards.展开更多
Township and Village Health Services Integration Management(TVHSIM) is an essential form of China's two-tiered health service integration plan at the township and village level. Its main purpose, also one of the ta...Township and Village Health Services Integration Management(TVHSIM) is an essential form of China's two-tiered health service integration plan at the township and village level. Its main purpose, also one of the target goals in China's new healthcare reform, is to gradually integrate rural health services and appropriately allocate rural health resources. This study aims to assess the village doctors' satisfaction with the TVHSIM and provide scientific base to further improve TVHSIM. A cross-sectional study was carried out in which 162 village doctors from Qinghai, Inner Mongolia and Xinjiang in western China were interviewed. Descriptive analysis, independent t-test, one-way ANOVA, Spearman rank correlation and multiple linear regression were used to analyze the difference and relevance between village doctors' personal characteristics and their satisfaction with TVHSIM and six subscales. Village doctors with different years of practice, social insurance status and essential medical knowledge level showed statistically significant differences in their satisfaction levels(all P〈0.05). Age(P〈0.05) and years of practice(P〈0.01) were negatively correlated with Drug and Medical Device Management and Financing Management. Essential medical knowledge level(P〈0.05) was negatively correlated with Operations Management as well. However, social insurance status(P〈0.05) was positively correlated with Human Resources Management and Drug and Medical Device management. Gender, age and years of practice respectively had significant influence on village doctors' satisfaction with TVHSIM(P〈0.01). In conclusion, in order to further promote TVHSIM policy in rural China, a well-rounded social insurance model for village doctors is urgently needed. In addition, the development of TVHSIM is regionally imbalanced. Efficient and effective measures aiming at rationalizing gender and age structure and enhancing essential medical training should be carefully considered.展开更多
The high market demand for endeavour shrimp(Metapenaeus ensis de Haan)has caused intensive fishing for this resource and tends to threaten their sustainability.Assessment of fishing dynamic and stock status of fisheri...The high market demand for endeavour shrimp(Metapenaeus ensis de Haan)has caused intensive fishing for this resource and tends to threaten their sustainability.Assessment of fishing dynamic and stock status of fisheries resource is the main point to formulate its proper sustainable management in the future.The purpose of this study was to determine the stock status of endeavour shrimp in the Bombana and its surrounding waters.The study was conducted from April to November 2021 using a survey method to analyze the length at first capture(L_(c)),length at first maturity(L_(m)),growth rate(K),maximum theoretical carapace length(Loo),and mortality rate such as total mortality rate(Z),fishing mortality rate(F)and natural mortality rate(M).The study results revealed that the endeavour shrimp growth pattern in Bombana was negative allometric and that the ratio of males and females was not balanced.The length at first capture(L_(c))was 29.83 mm(carapace length)and the length at first maturity(L_(m))was at a total carapace length of 31.67 mm.The growth rate(K)was 1.0 per year and maximum theoretical length(L_(∞))was 46.2 mm.The estimate total mortality rate(Z)was 2.52 per year,the fishing mortality rate(F)and natural mortality rate(M)were 0.91 per year and 1.61 per year respectively.The exploitation rate(E)was 0.36 per year,therefore the stock status is not categorized overfishing.In order to ensure the sustainability of the endeavour shrimp,then the effort must be increased by about 28%of the current effort.展开更多
An exploratory survey was conducted among the Khasia living in Lawachara National Parkt (LNP) to investigate their depend- ency on the protected area (PA) for livelihoods, betel leaf hill farming, traditional fore...An exploratory survey was conducted among the Khasia living in Lawachara National Parkt (LNP) to investigate their depend- ency on the protected area (PA) for livelihoods, betel leaf hill farming, traditional forest conservation and perceptions of the PA, Field data were collected by interviewing 48 household heads from two villages (punjis) located inside the LNP and visiting their farms.: The economy of the Khasia was forest-based. They were largely dependent on betel leaf hill farming in LNP and nearly 71% of their mean annual income was de- rived from this irrespective of farmer category. On average, about 14% of the incomes of the poorer farmers came from forest produce followed by 10% and 6% for medium and rich farmers respectively. Hills and forests were the foundations of their lives and livelihoods, and LNP was the life-blood of Khasia survival. As a sustainable production system, this farming practice plays a vital role in conserving biodiversity in LNP and might be replicated elsewhere.展开更多
Conversion of forest land to farmland in the Hyrcanian forest of northern Iran increases the nutrient input, especially the phosphorus(P) nutrient, thus impacting the water quality. Modeling the effect of forest los...Conversion of forest land to farmland in the Hyrcanian forest of northern Iran increases the nutrient input, especially the phosphorus(P) nutrient, thus impacting the water quality. Modeling the effect of forest loss on surface water quality provides valuable information for forest management. This study predicts the future impacts of forest loss between 2010 and 2040 on P loading in the Tajan River watershed at the sub-watershed level. To understand drivers of the land cover, we used Land Change Modeler(LCM) combining with the Soil Water Assessment Tool(SWAT) model to simulate the impacts of land use change on P loading. We characterized priority management areas for locating comprehensive and cost-effective management practices at the sub-watershed level. Results show that agricultural expansion has led to an intense deforestation. During the future period 2010–2040, forest area is expected to decrease by 34,739 hm^2. And the areas of pasture and agriculture are expected to increase by 7668 and 27,071 hm^2, respectively. In most sub-watersheds, P pollution will be intensified with the increase in deforestation by the year 2040. And the P concentration is expected to increase from 0.08 to 2.30 mg/L in all of sub-watersheds by the year 2040. It should be noted that the phosphorous concentration exceeds the American Public Health Association′s water quality standard of 0.2 mg/L for P in drinking water in both current and future scenarios in the Tajan River watershed. Only 30% of sub-watersheds will comply with the water quality standards by the year 2040. The finding of the present study highlights the importance of conserving forest area to maintain a stable water quality.展开更多
As a result of socio-economic changes and land abandonment,the main ecological driver of the Carpathian landscape is the progression of the natural forest succession process.Thus,aspects of this process have become wo...As a result of socio-economic changes and land abandonment,the main ecological driver of the Carpathian landscape is the progression of the natural forest succession process.Thus,aspects of this process have become worthy of attention,especially in the context of carbon sequestration and the management of protected areas.Soil processes,especially within the topsoil,are some of the most susceptible to change,due to the accumulation of organic matter during such land-use transformations.The purposes of this study were to investigate the differences in topsoil development using the A Horizon Development Index(ADI)and to study the composition of humic substances and advanced organic matter humification in different land-use areas in selected Carpathian national parks,i.e.Bieszczady,Magura and Pieniny National Parks in southern Poland.Additionally,a goal of this study was to compare the ADI and the spectroscopic coefficients of humic substances as indicators of the degree of humus horizon shaping as well as advanced organic matter humification.In total,ten transects were selected,each consisting of three different land-use areas:semi-natural meadow,successional forest and old-growth forest.Soil colour was determined in fresh and air-dried samples using the Munsell colour chart.In air-dried soil samples p H,soil texture,total organic carbon and total nitrogen were measured.Humic substances were extracted and further characterized by UV-VIS spectroscopy.The ADI confirmed the influence of natural forest succession on soil colour darkening and the development of the uppermost soil layer.Spectroscopic analyses of humic substances showed two different patterns depending on soil depth.In the 0–10 cm layer,natural forest succession reduced the rate of the humification process and decreased the degree of maturity of fulvic acids;in the 10–20 cm layer,it led to an increase in the rate of the humification process and a decrease in the content of humic and fulvic acids at the beginning of the transformation.The comparison of two different indicators of soil development–the ADI and the spectroscopic coefficients of humic substances(Q_(4/6),Q_(2/4),Q_(2/3),Δlog K)–indicated that these indexes are based on different features of soil and cannot be used interchangeably.展开更多
In Japan, each municipality generally has its own municipal solid waste incineration facilities because of the principle of self-management in the respective territories. Typically, a small municipality often owns a s...In Japan, each municipality generally has its own municipal solid waste incineration facilities because of the principle of self-management in the respective territories. Typically, a small municipality often owns a small facility. However, a large facility which can run continuously at high temperature with stability would be preferable if the dioxin generation mechanism is to be considered. Accordingly, municipalities in contiguous areas should cooperate mutually by using a large facility. To evaluate the effect of the concentration of large facilities, the authors created a GIS (Geographic Information System) based database of combustible waste generation at town level in Shizuoka Prefecture. Focusing on large facilities in Shizuoka City and superannuated facilities in Shida area, the authors evaluated the effect of the concentration of large facilities in Shizuoka city on utilization rate of facilities, energy balance and CO2 emissions. Our results showed the amount of light oil consumption and CO2 emissions increased because the mileage distance of garbage collection trucks becomes longer. However, the utilization rates of facilities and the amount of energy recovery from waste are improved. From these standpoints, the authors conclude that the concentration of large facilities is better compared to a single municipality based facility.展开更多
This paper proposes a neural-network-based state estimation(NNSE)method that aims to achieve higher time efficiency,improved robustness against noise,and extended observability when compared with the conventional weig...This paper proposes a neural-network-based state estimation(NNSE)method that aims to achieve higher time efficiency,improved robustness against noise,and extended observability when compared with the conventional weighted least squares(WLS)state estimation method.NNSE consists of two parts,the linear state estimation neural network(LSE-net)and the unobservable state estimation neural network(USE-net).The LSE-net functions as an adaptive approximator of linear state estimation(LSE)equations to estimate the nominally observable states.The inputs of LSE-net are the vectors of synchrophasors while the outputs are the estimated states.The USE-net operates as the complementary estimator on the nominally unobservable states.The inputs are the estimated observable states from LSE-net while the outputs are the estimation of nominally unobservable states.USE-net is trained off-line to approximate the veiled relationship between observable states and unobservable states.Two test cases are conducted to validate the performance of the proposed approach.The first case,which is based on the IEEE 118-bus system,shows the comprehensive performance of convergence,accuracy,and robustness of the proposed approach.The second case study adopts real-world synchrophasor measurements,and is based on the Jiangsu power grid,which is one of the largest provincial power systems in China.展开更多
Camivores play a central role in ecosystem processes by exerting top-down control, while fire exerts bottom-up con- trol in ecosystems throughout the world, yet, little is known about how fire affects short-term carni...Camivores play a central role in ecosystem processes by exerting top-down control, while fire exerts bottom-up con- trol in ecosystems throughout the world, yet, little is known about how fire affects short-term carnivore distributions across the landscape. Through the use of a long-term data set we investigated the distribution of lions, during the daytime, in relation to burned areas in Serengeti National Park, Tanzania. We found that lions avoid burned areas despite the fact that herbivores, their prey, are attracted to burned areas. Prey attraction, however, likely results from the reduction in cover caused by burning, that may thereby decrease lion hunting success. Lions also do not preferentially utilize the edges of burned areas over unburned areas de- spite the possibility that edges would combine the benefit of cover with proximity to abundant prey. Despite the fact that lions avoid burned areas, lion territory size and reproductive success were not affected by the proportion of the territory burned each year. Therefore, burning does not seem to reduce lion fitness perhaps because of the heterogeneity of burned areas across the landscape or because it is possible that when hunting at night lions visit burned areas despite their daytime avoidance of these ar- eas .展开更多
Queensland fruit fly[Bactrocera Uyoni(Froggatt),Diptera,Tephritidae]is the most devastating insect pest impacting Australian horticulture.The Sterile Insect Technique(SIT)is an important component of tephritid pest ma...Queensland fruit fly[Bactrocera Uyoni(Froggatt),Diptera,Tephritidae]is the most devastating insect pest impacting Australian horticulture.The Sterile Insect Technique(SIT)is an important component of tephritid pest management programs.However,mass-rearing and irradiation(to render insects sterile)may reduce the fitness and performance of the insect,including the ability of sterile males to successfully compete for wild females.Manipulation of the gut microbiome,including the supplementation with bacterial probiotics shows promise for enhancing the quality of mass-reared sterile flies,however there are fewer published studies targeting the larval stage.In this study,we supplemented the larval stage of mass-reared B.tryoni with bacterial probiotics.We tested several individual bacteria that had been previously isolated and characterized from the gut of wild B.tryoni larvae including Asaia sp.,Enterobacter sp.,Lactobacillus sp.,Leuconostoc sp.We also tested a consortium of all four of these bacterial isolates.The fitness parameters tested included adult survival in field cages,laboratory mate selection of bacteria supplemented males by bacteria nonsupplemented females,and laboratory locomotor activity of adult flies.None of the bacterial probiotic treatments in the current study was significantly different to the control for field survival,mate selection or locomotor activity of adult B.Uyoni,which agree with some of the other studies regarding bacterial probiotics fed to the larval stage of tephritids.Future work is needed to determine if feeding the same,and/or other probiotics to adults,as opposed to larvae can positively impact survival,mating performance,mating competitiveness and locomotor activity of B.tryoni.The bacterial group(s)and function of bacterial species that increase fitness and competitiveness is also of interest to tephritid mass-rearing programs.展开更多
基金supported partially by AirForce Research Laboratory,the Office of the Secretary of Defense(OSD)(FA8750-15-2-0116)the National Science Foundation(NSF)(1832110)the National Institute of Aerospace and Langley(C16-2B00-NCAT)。
文摘Timely investigating post-disaster situations to locate survivors and secure hazardous sources is critical,but also very challenging and risky.Despite first responders putting their lives at risk in saving others,human-physical limits cause delays in response time,resulting in fatality and property damage.In this paper,we proposed and implemented a framework intended for creating collaboration between heterogeneous unmanned vehicles and first responders to make search and rescue operations safer and faster.The framework consists of unmanned aerial vehicles(UAVs),unmanned ground vehicles(UGVs),a cloud-based remote control station(RCS).A light-weight message queuing telemetry transport(MQTT)based communication is adopted for facilitating collaboration between autonomous systems.To effectively work under unfavorable disaster conditions,antenna tracker is developed as a tool to extend network coverage to distant areas,and mobile charging points for the UAVs are also implemented.The proposed framework’s performance is evaluated in terms of end-to-end delay and analyzed using architectural analysis and design language(AADL).Experimental measurements and simulation results show that the adopted communication protocol performs more efficiently than other conventional communication protocols,and the implemented UAV control mechanisms are functioning properly.Several scenarios are implemented to validate the overall effectiveness of the proposed framework and demonstrate possible use cases.
基金supported by the Fundamental Research Funds for the Central Universities (Grant No. 2011YYL141)
文摘The Three Gorges project accelerates economic development in the Three Gorges Reservoir Area.This paper aimed to investigate the distribution,changes and features of cultivated land in this area,analyze the forces driving the changes in cultivated land area,and propose the countermeasures for cultivated land management.Transition matrix was used to analyze the features of cultivated land changes,and quantitative analysis and qualitative analysis were adopted to research the driving forces according to the features of cultivated land changes.Cultivated land in the Three Gorges Reservoir Area mainly lay to the northwest of the Yangtze River,especially the upper reaches.The areas of cultivated land increased from 1996 to 1999,then decreased from 2000 to 2006,and finally increased again from 2007 to 2009.The important forces driving changes in cultivated land included government policies,employment and food security,increasing construction land,agriculture structure adjustment,land rearrangement,inundation.During cultivated land management,firstly,it is necessary to insist on the principle of cultivated land protection,standardize land exploitation and strictly restrict the transformation of cultivated land into non-farming land.Secondly,land rearrangement must be implemented,which can not only increase the area of the cultivated land,but also improve the quality of the cultivated land.Thirdly,it is feasible to intensify eco-agriculture construction to increase the quantity and quality of cultivated land.Fourthly,it is helpful to improve the traditional agriculture production methods to promote cultivated land quality.Lastly,it is important to propagandize cultivated land protection and realize the enormous pressure of cultivated land shortage,making more people obligated to protect cultivated land.
文摘Based on the Intranet technique,the design and implementation of rural area electricity Management Information System(RAEMIS)is researched.And then,a new RAEMIS with opening dynamic multimedia hypertext architecture is proposed.The advantages of new system include uniform user interface friendly,quick and accurate database accessing,and easy maintenance.
基金funded by the Knowledge Innovation Program of Chinese Academy of Sciences(KZCX2-SW-415,KZCX3-SW-426).
文摘Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studied. Fixed observation results from 1993to 2002 showed that pools covering about 15% of total area could store up 10% of surfacerunoff, keep 78.1% of eroded soil and 65.4% of lost nutrients. The yearly ratio ofinterception and evapotranspiration in land, storage in pools and drainage was 7:2:1,which ensured the resources and nutrients equilibrium and a benign recycle in thecatchment area system, and benefited the aquatic culture and helped to resist seasonaldrought. Moreover, the results showed that soil erosion modulus decreased significantly,equal to or lower than soil loss tolerance (≤500 tkm-2) in reddish yellow soil regions.Soil organic matter, total and available N content in sloping land, dryland and paddyfield increased steadily (>10%); water storage enhanced by more than 20% in sloping landand dryland in drought season; crop production increased by more than 20%; and productionof trees, fruits, tea and fish as well as land productivity increased yearly.
文摘The management of sea area useplays an important role in safeguardingthe reasonable development and useof sea area resources and the healthyand orderly development of the marineeconomy.It is therefore a major componentof marine management.Thispaper outlines the construction of astandards system for sea area usemanagement,and looks at the system'sstructure,as well as the numberof standards and the scope of thestandards system.In addition,the paperelaborates on the important functionof the standards system in themanagement of sea area use,andproposes measures aimed at furtherimproving the management,formulation,implementation and revision ofstandards.
基金supported by the National Natural Science Foundation of China(No.71273097)
文摘Township and Village Health Services Integration Management(TVHSIM) is an essential form of China's two-tiered health service integration plan at the township and village level. Its main purpose, also one of the target goals in China's new healthcare reform, is to gradually integrate rural health services and appropriately allocate rural health resources. This study aims to assess the village doctors' satisfaction with the TVHSIM and provide scientific base to further improve TVHSIM. A cross-sectional study was carried out in which 162 village doctors from Qinghai, Inner Mongolia and Xinjiang in western China were interviewed. Descriptive analysis, independent t-test, one-way ANOVA, Spearman rank correlation and multiple linear regression were used to analyze the difference and relevance between village doctors' personal characteristics and their satisfaction with TVHSIM and six subscales. Village doctors with different years of practice, social insurance status and essential medical knowledge level showed statistically significant differences in their satisfaction levels(all P〈0.05). Age(P〈0.05) and years of practice(P〈0.01) were negatively correlated with Drug and Medical Device Management and Financing Management. Essential medical knowledge level(P〈0.05) was negatively correlated with Operations Management as well. However, social insurance status(P〈0.05) was positively correlated with Human Resources Management and Drug and Medical Device management. Gender, age and years of practice respectively had significant influence on village doctors' satisfaction with TVHSIM(P〈0.01). In conclusion, in order to further promote TVHSIM policy in rural China, a well-rounded social insurance model for village doctors is urgently needed. In addition, the development of TVHSIM is regionally imbalanced. Efficient and effective measures aiming at rationalizing gender and age structure and enhancing essential medical training should be carefully considered.
文摘The high market demand for endeavour shrimp(Metapenaeus ensis de Haan)has caused intensive fishing for this resource and tends to threaten their sustainability.Assessment of fishing dynamic and stock status of fisheries resource is the main point to formulate its proper sustainable management in the future.The purpose of this study was to determine the stock status of endeavour shrimp in the Bombana and its surrounding waters.The study was conducted from April to November 2021 using a survey method to analyze the length at first capture(L_(c)),length at first maturity(L_(m)),growth rate(K),maximum theoretical carapace length(Loo),and mortality rate such as total mortality rate(Z),fishing mortality rate(F)and natural mortality rate(M).The study results revealed that the endeavour shrimp growth pattern in Bombana was negative allometric and that the ratio of males and females was not balanced.The length at first capture(L_(c))was 29.83 mm(carapace length)and the length at first maturity(L_(m))was at a total carapace length of 31.67 mm.The growth rate(K)was 1.0 per year and maximum theoretical length(L_(∞))was 46.2 mm.The estimate total mortality rate(Z)was 2.52 per year,the fishing mortality rate(F)and natural mortality rate(M)were 0.91 per year and 1.61 per year respectively.The exploitation rate(E)was 0.36 per year,therefore the stock status is not categorized overfishing.In order to ensure the sustainability of the endeavour shrimp,then the effort must be increased by about 28%of the current effort.
文摘An exploratory survey was conducted among the Khasia living in Lawachara National Parkt (LNP) to investigate their depend- ency on the protected area (PA) for livelihoods, betel leaf hill farming, traditional forest conservation and perceptions of the PA, Field data were collected by interviewing 48 household heads from two villages (punjis) located inside the LNP and visiting their farms.: The economy of the Khasia was forest-based. They were largely dependent on betel leaf hill farming in LNP and nearly 71% of their mean annual income was de- rived from this irrespective of farmer category. On average, about 14% of the incomes of the poorer farmers came from forest produce followed by 10% and 6% for medium and rich farmers respectively. Hills and forests were the foundations of their lives and livelihoods, and LNP was the life-blood of Khasia survival. As a sustainable production system, this farming practice plays a vital role in conserving biodiversity in LNP and might be replicated elsewhere.
基金The Modares Tarbiat University of Iran funded this work
文摘Conversion of forest land to farmland in the Hyrcanian forest of northern Iran increases the nutrient input, especially the phosphorus(P) nutrient, thus impacting the water quality. Modeling the effect of forest loss on surface water quality provides valuable information for forest management. This study predicts the future impacts of forest loss between 2010 and 2040 on P loading in the Tajan River watershed at the sub-watershed level. To understand drivers of the land cover, we used Land Change Modeler(LCM) combining with the Soil Water Assessment Tool(SWAT) model to simulate the impacts of land use change on P loading. We characterized priority management areas for locating comprehensive and cost-effective management practices at the sub-watershed level. Results show that agricultural expansion has led to an intense deforestation. During the future period 2010–2040, forest area is expected to decrease by 34,739 hm^2. And the areas of pasture and agriculture are expected to increase by 7668 and 27,071 hm^2, respectively. In most sub-watersheds, P pollution will be intensified with the increase in deforestation by the year 2040. And the P concentration is expected to increase from 0.08 to 2.30 mg/L in all of sub-watersheds by the year 2040. It should be noted that the phosphorous concentration exceeds the American Public Health Association′s water quality standard of 0.2 mg/L for P in drinking water in both current and future scenarios in the Tajan River watershed. Only 30% of sub-watersheds will comply with the water quality standards by the year 2040. The finding of the present study highlights the importance of conserving forest area to maintain a stable water quality.
基金supported by Statutory financial support of Ministry of Science and Higher Education RP Department of Soil Science and Agrophysics[010013D011 in 2021]University of Agriculture in Krakow。
文摘As a result of socio-economic changes and land abandonment,the main ecological driver of the Carpathian landscape is the progression of the natural forest succession process.Thus,aspects of this process have become worthy of attention,especially in the context of carbon sequestration and the management of protected areas.Soil processes,especially within the topsoil,are some of the most susceptible to change,due to the accumulation of organic matter during such land-use transformations.The purposes of this study were to investigate the differences in topsoil development using the A Horizon Development Index(ADI)and to study the composition of humic substances and advanced organic matter humification in different land-use areas in selected Carpathian national parks,i.e.Bieszczady,Magura and Pieniny National Parks in southern Poland.Additionally,a goal of this study was to compare the ADI and the spectroscopic coefficients of humic substances as indicators of the degree of humus horizon shaping as well as advanced organic matter humification.In total,ten transects were selected,each consisting of three different land-use areas:semi-natural meadow,successional forest and old-growth forest.Soil colour was determined in fresh and air-dried samples using the Munsell colour chart.In air-dried soil samples p H,soil texture,total organic carbon and total nitrogen were measured.Humic substances were extracted and further characterized by UV-VIS spectroscopy.The ADI confirmed the influence of natural forest succession on soil colour darkening and the development of the uppermost soil layer.Spectroscopic analyses of humic substances showed two different patterns depending on soil depth.In the 0–10 cm layer,natural forest succession reduced the rate of the humification process and decreased the degree of maturity of fulvic acids;in the 10–20 cm layer,it led to an increase in the rate of the humification process and a decrease in the content of humic and fulvic acids at the beginning of the transformation.The comparison of two different indicators of soil development–the ADI and the spectroscopic coefficients of humic substances(Q_(4/6),Q_(2/4),Q_(2/3),Δlog K)–indicated that these indexes are based on different features of soil and cannot be used interchangeably.
文摘In Japan, each municipality generally has its own municipal solid waste incineration facilities because of the principle of self-management in the respective territories. Typically, a small municipality often owns a small facility. However, a large facility which can run continuously at high temperature with stability would be preferable if the dioxin generation mechanism is to be considered. Accordingly, municipalities in contiguous areas should cooperate mutually by using a large facility. To evaluate the effect of the concentration of large facilities, the authors created a GIS (Geographic Information System) based database of combustible waste generation at town level in Shizuoka Prefecture. Focusing on large facilities in Shizuoka City and superannuated facilities in Shida area, the authors evaluated the effect of the concentration of large facilities in Shizuoka city on utilization rate of facilities, energy balance and CO2 emissions. Our results showed the amount of light oil consumption and CO2 emissions increased because the mileage distance of garbage collection trucks becomes longer. However, the utilization rates of facilities and the amount of energy recovery from waste are improved. From these standpoints, the authors conclude that the concentration of large facilities is better compared to a single municipality based facility.
基金This work was supported by the State Grid Corporation of China(No.SGJS0000DKJS1801231).
文摘This paper proposes a neural-network-based state estimation(NNSE)method that aims to achieve higher time efficiency,improved robustness against noise,and extended observability when compared with the conventional weighted least squares(WLS)state estimation method.NNSE consists of two parts,the linear state estimation neural network(LSE-net)and the unobservable state estimation neural network(USE-net).The LSE-net functions as an adaptive approximator of linear state estimation(LSE)equations to estimate the nominally observable states.The inputs of LSE-net are the vectors of synchrophasors while the outputs are the estimated states.The USE-net operates as the complementary estimator on the nominally unobservable states.The inputs are the estimated observable states from LSE-net while the outputs are the estimation of nominally unobservable states.USE-net is trained off-line to approximate the veiled relationship between observable states and unobservable states.Two test cases are conducted to validate the performance of the proposed approach.The first case,which is based on the IEEE 118-bus system,shows the comprehensive performance of convergence,accuracy,and robustness of the proposed approach.The second case study adopts real-world synchrophasor measurements,and is based on the Jiangsu power grid,which is one of the largest provincial power systems in China.
基金We thank the Tanzania Wildlife Re- search Institute, Tanzania National Parks and Tanzania Com- mission for Science and Technology for permission to conduct research in the Serengeti. This work was supported by Na-tional Science Foundation grants DEB 0308486 to C.E and M.R., 9903416 and 0343960 to C.P., and 0543398, and 0842230 to M.R.
文摘Camivores play a central role in ecosystem processes by exerting top-down control, while fire exerts bottom-up con- trol in ecosystems throughout the world, yet, little is known about how fire affects short-term carnivore distributions across the landscape. Through the use of a long-term data set we investigated the distribution of lions, during the daytime, in relation to burned areas in Serengeti National Park, Tanzania. We found that lions avoid burned areas despite the fact that herbivores, their prey, are attracted to burned areas. Prey attraction, however, likely results from the reduction in cover caused by burning, that may thereby decrease lion hunting success. Lions also do not preferentially utilize the edges of burned areas over unburned areas de- spite the possibility that edges would combine the benefit of cover with proximity to abundant prey. Despite the fact that lions avoid burned areas, lion territory size and reproductive success were not affected by the proportion of the territory burned each year. Therefore, burning does not seem to reduce lion fitness perhaps because of the heterogeneity of burned areas across the landscape or because it is possible that when hunting at night lions visit burned areas despite their daytime avoidance of these ar- eas .
文摘Queensland fruit fly[Bactrocera Uyoni(Froggatt),Diptera,Tephritidae]is the most devastating insect pest impacting Australian horticulture.The Sterile Insect Technique(SIT)is an important component of tephritid pest management programs.However,mass-rearing and irradiation(to render insects sterile)may reduce the fitness and performance of the insect,including the ability of sterile males to successfully compete for wild females.Manipulation of the gut microbiome,including the supplementation with bacterial probiotics shows promise for enhancing the quality of mass-reared sterile flies,however there are fewer published studies targeting the larval stage.In this study,we supplemented the larval stage of mass-reared B.tryoni with bacterial probiotics.We tested several individual bacteria that had been previously isolated and characterized from the gut of wild B.tryoni larvae including Asaia sp.,Enterobacter sp.,Lactobacillus sp.,Leuconostoc sp.We also tested a consortium of all four of these bacterial isolates.The fitness parameters tested included adult survival in field cages,laboratory mate selection of bacteria supplemented males by bacteria nonsupplemented females,and laboratory locomotor activity of adult flies.None of the bacterial probiotic treatments in the current study was significantly different to the control for field survival,mate selection or locomotor activity of adult B.Uyoni,which agree with some of the other studies regarding bacterial probiotics fed to the larval stage of tephritids.Future work is needed to determine if feeding the same,and/or other probiotics to adults,as opposed to larvae can positively impact survival,mating performance,mating competitiveness and locomotor activity of B.tryoni.The bacterial group(s)and function of bacterial species that increase fitness and competitiveness is also of interest to tephritid mass-rearing programs.