An effective evaluation system can provide specific and practical suggestions to the deep groundwater management. But such kind of evaluation system has not been proposed in China. In this study, an evaluation index s...An effective evaluation system can provide specific and practical suggestions to the deep groundwater management. But such kind of evaluation system has not been proposed in China. In this study, an evaluation index system is specifically developed to evaluate deep groundwater management efficiency. It is composed of three first-level indicators(law enforcement capability, management ability, and management effectiveness) and eleven second-level indicators. The second-level indicators include seven mandatory indicators and four optional indicators. Piecewise linear function is used to normalize the quantitative indicators, and expert scoring method and questionnaire survey method are used to normalize the qualitative indicators. Then a comprehensive indicator weighting evaluation method is used to evaluate the first-level indicators and the target topic. A case study is carried out to evaluate deep groundwater management efficiency in Tianjin City. According to the evaluation score in each period, the management efficiency of every district in Tianjin City gradually improved. The overall evaluation score in the early deep groundwater extraction period is 0.12. After a series of deep groundwater protection efforts, this score reached to 0.61 in 2007, and met the regulation criteria. The evaluation results also showed that the further groundwater management efforts in Tianjin City should be focused on building a dynamic database to collect comprehensive deep well-log data; and on a reasonable design and distribution of the groundwater monitoring network. It demonstrated that the index system is suitable to locate the deficiencies of current groundwater management systems and to guide further improvements. It can then be used to protect deep groundwater.展开更多
The evaluation of simulated disasters(for example,exercises)and real responses are important activities.However,little attention has been paid to how reports documenting such events should be written.A key issue is ho...The evaluation of simulated disasters(for example,exercises)and real responses are important activities.However,little attention has been paid to how reports documenting such events should be written.A key issue is how to make them as useful as possible to professionals working in disaster risk management.Here,we focus on three aspects of a written evaluation:how the object of the evaluation is described,how the analysis is described,and how the conclusions are described.This empirical experiment,based on real evaluation documents,asked 84 Dutch mayors and crisis management professionals to evaluate the perceived usefulness of the three aspects noted above.The results showed that how evalua・tions are written does matter.Specifically,the usefulness of an evaluation intended for learning purposes is improved when its analysis and conclusions are clearer.In contrast,evaluations used for accountability purposes are only improved by the clarity of the con elusion.These findings have implications for the way disaster management evaluations should be documented.展开更多
Natural mortality rate（M） is one of the essential parameters in fishery stock assessment, however, the estimation of M is commonly rough and the changes of M due to natural and anthropogenic impacts have long been i...Natural mortality rate（M） is one of the essential parameters in fishery stock assessment, however, the estimation of M is commonly rough and the changes of M due to natural and anthropogenic impacts have long been ignored.The simplification of M estimation and the influence of M variations on the assessment and management of fisheries stocks have been less well understood. This study evaluated the impacts of the changes in natural mortality of Spanish mackerel（Scomberomorus niphonius） on their management strategies with data-limited methods. We tested the performances of a variety of management procedures（MPs） with the variations of M in mackerel stock using diverse estimation methods. The results of management strategies evaluation showed that four management procedures DCAC, SPMSY, cur E75 and minlen Lopt1 were more robust to the changes of M than others; however, their performance were substantially influenced by the significant decrease of M from the 1970s to 2017. Relative population biomass（measure as the probability of B〉0.5 BMSY） increased significantly with the decrease of M, whereas the possibility of overfishing showed remarkable variations across MPs. The decrease of M had minor effects on the long-term yield of cur E75 and minlen Lopt1, and reduced the fluctuation of yield（measure as the probability of AAVY〈15%） for DCAC, SPMSY. In general, the different methods for M estimation showed minor effects on the performance of MPs, whereas the temporal changes of M showed substantial influences. Considering the fishery status of Spanish mackerel in China, we recommended that cur E75 has the best trade-off between fishery resources exploitation and conservation, and we also proposed the potentials and issues in their implementations.展开更多
The stock of Bigeye tuna(Thunnus obesus) in the Indian Ocean supports an important international fishery and is considered to be fully exploited. The responsible management agency, the Indian Ocean Tuna Commission(IOT...The stock of Bigeye tuna(Thunnus obesus) in the Indian Ocean supports an important international fishery and is considered to be fully exploited. The responsible management agency, the Indian Ocean Tuna Commission(IOTC), does not have an explicit management decision-making framework in place to prevent over-fishing. In this study, we evaluated three harvest control rules, i) constant fishing mortality(CF), from 0.2 to 0.6, ii) constant catch(CC), from 60000 to 140000 t, and iii) constant escapement(CE), from 0.3 to 0.7. The population dynamics simulated by the operating model was based on the most recent stock assessment using Stock Synthesis version Ⅲ(SS3). Three simulation scenarios(low, medium and high productivity) were designed to cover possible uncertainty in the stock assessment and biological parameters. Performances of three harvest control rules were compared on the basis of three management objectives(over 3, 10 and 25 years): i) the probability of maintaining spawning stock biomass above a level that can sustain maximum sustainable yield(MSY) on average, ii) the probability of achieving average catches between 0.8 MSY and 1.0 MSY, and iii) inter-annual variability in catches. The constant escapement strategy(CE=0.5), constant fishing mortality strategy(F=0.4) and constant catch(CC=80000) were the most rational among the respective management scenarios. It is concluded that the short-term annual catch is suggested at 80000 t, and the potential total allowable catch for a stable yield could be set at 120000 t once the stock had recovered successfully. All the strategies considered in this study to achieve a ‘tolerable' balance between resource conservation and utilization have been based around the management objectives of the IOTC.展开更多
This paper puts forward the connotation of enterprise green management and green management performance evaluation,analyzes the characteristics of enterprise green management performance evaluation and decomposes its ...This paper puts forward the connotation of enterprise green management and green management performance evaluation,analyzes the characteristics of enterprise green management performance evaluation and decomposes its content.Using the triple performance method,the paper constructs the performance evaluation index system of enterprise green management.Taking BH Petrochemical Co.,Ltd.at the high-efficiency ecological economic zone of the Yellow River Delta as an example,by using analytic hierarchy process(AHP)and Matlab programming,this paper determines the weight of each index in the enterprise green management performance evaluation index system,the fuzzy comprehensive evaluation method is used to evaluate the green management performance evaluation of industrial enterprises.The results show that the performance evaluation index system of enterprise green management constructed by"triple performance method"has important theoretical significance and application value for evaluating and guiding enterprises to strengthen their green management.展开更多
This paper analyses the necessity of developing variation information management of construction project. The structure scheme of variation management system has been put forward, which is based on intranet or interne...This paper analyses the necessity of developing variation information management of construction project. The structure scheme of variation management system has been put forward, which is based on intranet or internet scheme, with the structure of Browser or Server. The system consists of eight modules, which are variation account management, variation application, variation evaluation, variation execution, variation price management, variation report management, variation information query and system maintenance. With this system, remote management and controlling in real time for variation of construction proiect can be carried out.展开更多
For training forestry and agricultural mechanical post-graduates＇ innovation ability. This paper studied some problems hindering students improvement, mean value and standard deviation of time management tendency of ...For training forestry and agricultural mechanical post-graduates＇ innovation ability. This paper studied some problems hindering students improvement, mean value and standard deviation of time management tendency of students were researched. The results showed, graduate enthusiasm should be mobilized, curriculum should be optimized, new teaching methods should be introduced, practice should be strengthened and paid more attention, a strict system of management and evaluation should be established展开更多
Background: As one of the most common endocrinal disorders for women at childbearing age, the diagnostic criteria of polycystic ovary syndrome (PCOS) have been defined differently among different international health ...Background: As one of the most common endocrinal disorders for women at childbearing age, the diagnostic criteria of polycystic ovary syndrome (PCOS) have been defined differently among different international health organizations. Phenotypic heterogeneity of PCOS also brings about difficulties for its diagnosis and management assessment. Therefore, more efficient biomarkers representing the progression of PCOS are expected to be integrated into the monitoring of management process using metabolomic approaches.Methods: In this prospective randomized controlled trial, 117 PCOS patients were enrolled from December 2016 to September 2017. Classical diagnostic parameters, blood glucose, and metabolome were measured in these patients before and at 2 months and 3 months of different medical interventions. The receiver operating characteristic (ROC) curves were built based on multivariate statistical analysis using data at baseline and 3 months’ management, and combinational biomarkers with appreciable sensitivity and specificity were selected, which then validated with data collected at 2 months.Results: A set of metabolites including glutamic acid, aspartic acid, 1-methylnicotinamide, acetylcarnitine, glycerophosphocholine, and oleamide were filtered out with high performance in representing the improvement through 3-month management of PCOS with high sensitivity and specificity in ROC analysis and validation with other two groups showed an appreciable area under the curve over 0.96.Conclusions: The six metabolites were representative of the remission of PCOS through medical intervention, making them a set of potential biomarkers for assessing the outcome of PCOS management.Trial Registration: ClinicalTrials.gov, NCT03264638.展开更多
The linchpin of strategy about the Sustainable Development (SD) in Chinese county enforcement area is to accomplish the basic transformation about the mode of economic development from extensive mode to intensive mode...The linchpin of strategy about the Sustainable Development (SD) in Chinese county enforcement area is to accomplish the basic transformation about the mode of economic development from extensive mode to intensive mode. For most counties of China, the overmany population is an element which influences the Sustainable Development. But to achieve the Sustainable Development based on the harmonious development of population, resource, economy and environment, the most important thing is how to carry on its management and evaluation method under the guide of the Tenth Five Year Plan of national economy and the Perspective Target of 2010.Therefore,this paper aims at reforming the traditional judging method focusing on output value Income and establishing a systematic management method and evaluation index system about the sustainable development based on the harmonious growth of population, resource, economy and environment.展开更多
Aiming to provide a measurable service Quality of Service （ QoS） evaluating method for service inventory management, this paper proposes a new mobile Service Utility Model （SUM）, considers the service and business...Aiming to provide a measurable service Quality of Service （ QoS） evaluating method for service inventory management, this paper proposes a new mobile Service Utility Model （SUM）, considers the service and business layer elements into the service utility influence profile, and proposes an self-adaptive service inventory management algorithm as a QoS control scheme based on SUM. It can be concluded from the simulation result that the service inventory utility can be fully reflected by SUM and the whole system efficiency is greatly increased by using SUM as the adaptive rule.展开更多
Spatial management of fishing effort can be used to avoid catching undesirable size classes for target species,and improve yield-per-recruit for the exploited stock.Adaptive closure management has been proposed as a m...Spatial management of fishing effort can be used to avoid catching undesirable size classes for target species,and improve yield-per-recruit for the exploited stock.Adaptive closure management has been proposed as a means to more effectively utilise spatial management,however these management provisions often lack quantitative evaluation which constrains the information available to inform decisions.We demonstrate the use of a spatially and size structured population dynamics model to evaluate the potential impact of spatial management on a multijurisdictional fishery for a highly migratory species(eastern king prawn,Penaeus[Melicertus]plebejus).Under current conditions in the fishery,the overall effect of closures on harvest was estimated to be comparatively minor,regardless of assumptions about how effort or fisher behavior are affected by spatial management.Alternative assumptions about the movement patterns of eastern king prawn had little influence on the impact of closures on overall harvest.However,when effort was increased to historic levels similar to those observed when the closures were implemented,a much greater impact on overall harvest was observed.The approach taken and simulation outcomes are discussed in the context of spatial management for both eastern king prawn,and penaeid fisheries more broadly.展开更多
Responsible stock enhancement initiatives require baseline data of wild population demographic conditions that can be used in testing management outcomes.This study provides the first fishery-independent assessment of...Responsible stock enhancement initiatives require baseline data of wild population demographic conditions that can be used in testing management outcomes.This study provides the first fishery-independent assessment of length-and age-based biological characteristics of exploited populations of Platycephalus fuscus in eastern Australia prior to stock enhancement.Sampling was conducted over seven estuaries spanning seven degrees of latitude and the geographical range of proposed stock enhancements.Populations in all estuaries showed evidence of length and age truncation,especially those subject to commercial fisheries where young individuals of both sexes dominated populations.Maximum longevities were 12 and 11 years for females and males respectively,but few females>5 years and males>3 years were generally sampled.Females dominated populations,and on average,the mean lengths and ages of females were greater than males within each estuary and across all age classes.Sexually dimorphic variation in growth was evident across all estuaries,with females attaining greater maximum lengths than males.Estuary-specific differences in individual growth were not identified.On average,over 50%of females sampled in each estuary were>the minimum legal length(MLL),but the opposite was evident for males.In contrast,over 25%of males in each estuary were>the mean length at maturity(L50),whereas in all but one estuary<13%of the females were>the L50.Stocked male and female P.fuscus should recruit to the fishery in 2 and 3 years,and contribute to the spawning stock in 1.5 and 4.5 years,respectively.This study provides important historical baseline data that can contribute to testing stock enhancement outcomes on populations.展开更多
Biological reference point(BRP)is one of the essential components in the management strategy evaluation that is used to determine the status of fishery stock and set management regulations.However,as BRPs can be deriv...Biological reference point(BRP)is one of the essential components in the management strategy evaluation that is used to determine the status of fishery stock and set management regulations.However,as BRPs can be derived from different models and many different BRPs are available,the effectiveness and consistency of different BRPs should be evaluated before being applied to fisheries management.In this study,we used a computation-intensive approach to identify optimal BRPs.We systematically evaluated 1500 combinations of alternative BRPs in managing the bigeye tuna(Thunnus obesus)and yellowfin tuna(Thunnus albacares)fisheries in the Indian Ocean.The effectiveness and consistency of these BRPs were evaluated using four performance measures related to fisheries landing performance and biomass conservation.Monte Carlo simulation was used to evaluate various uncertainties.The results suggest that the proposed computation-intensive approach can be effective in identifying optimal BRPs with respect to a set of defined performance measures.We found that the current maximum sustainable yield(MSY)-based BRP combinations are effective target BRPs to manage the bigeye and yellowfin tuna fisheries with the“linear”harvest control rule(HCR).However,using the“knife-edge”HCR,better BRPs could be found for both the bigeye and yellowfin tuna fisheries management with improved fisheries and conservation performance.The framework developed in this study can be used to identify suitable BRPs based on a set of defined performance measures for other fisheries.展开更多
基金Under the auspices of National Basic Research Program of China(No.2010CB428804)
文摘An effective evaluation system can provide specific and practical suggestions to the deep groundwater management. But such kind of evaluation system has not been proposed in China. In this study, an evaluation index system is specifically developed to evaluate deep groundwater management efficiency. It is composed of three first-level indicators(law enforcement capability, management ability, and management effectiveness) and eleven second-level indicators. The second-level indicators include seven mandatory indicators and four optional indicators. Piecewise linear function is used to normalize the quantitative indicators, and expert scoring method and questionnaire survey method are used to normalize the qualitative indicators. Then a comprehensive indicator weighting evaluation method is used to evaluate the first-level indicators and the target topic. A case study is carried out to evaluate deep groundwater management efficiency in Tianjin City. According to the evaluation score in each period, the management efficiency of every district in Tianjin City gradually improved. The overall evaluation score in the early deep groundwater extraction period is 0.12. After a series of deep groundwater protection efforts, this score reached to 0.61 in 2007, and met the regulation criteria. The evaluation results also showed that the further groundwater management efforts in Tianjin City should be focused on building a dynamic database to collect comprehensive deep well-log data; and on a reasonable design and distribution of the groundwater monitoring network. It demonstrated that the index system is suitable to locate the deficiencies of current groundwater management systems and to guide further improvements. It can then be used to protect deep groundwater.
基金funding from the Institute for Safety(IFV)of the Netherlands and the Swedish Civil Contingencies Agency(MSB).
文摘The evaluation of simulated disasters(for example,exercises)and real responses are important activities.However,little attention has been paid to how reports documenting such events should be written.A key issue is how to make them as useful as possible to professionals working in disaster risk management.Here,we focus on three aspects of a written evaluation:how the object of the evaluation is described,how the analysis is described,and how the conclusions are described.This empirical experiment,based on real evaluation documents,asked 84 Dutch mayors and crisis management professionals to evaluate the perceived usefulness of the three aspects noted above.The results showed that how evalua・tions are written does matter.Specifically,the usefulness of an evaluation intended for learning purposes is improved when its analysis and conclusions are clearer.In contrast,evaluations used for accountability purposes are only improved by the clarity of the con elusion.These findings have implications for the way disaster management evaluations should be documented.
基金The Fundamental Research Funds for the Central Universities under contract Nos 201562030 and 201612004
文摘Natural mortality rate（M） is one of the essential parameters in fishery stock assessment, however, the estimation of M is commonly rough and the changes of M due to natural and anthropogenic impacts have long been ignored.The simplification of M estimation and the influence of M variations on the assessment and management of fisheries stocks have been less well understood. This study evaluated the impacts of the changes in natural mortality of Spanish mackerel（Scomberomorus niphonius） on their management strategies with data-limited methods. We tested the performances of a variety of management procedures（MPs） with the variations of M in mackerel stock using diverse estimation methods. The results of management strategies evaluation showed that four management procedures DCAC, SPMSY, cur E75 and minlen Lopt1 were more robust to the changes of M than others; however, their performance were substantially influenced by the significant decrease of M from the 1970s to 2017. Relative population biomass（measure as the probability of B〉0.5 BMSY） increased significantly with the decrease of M, whereas the possibility of overfishing showed remarkable variations across MPs. The decrease of M had minor effects on the long-term yield of cur E75 and minlen Lopt1, and reduced the fluctuation of yield（measure as the probability of AAVY〈15%） for DCAC, SPMSY. In general, the different methods for M estimation showed minor effects on the performance of MPs, whereas the temporal changes of M showed substantial influences. Considering the fishery status of Spanish mackerel in China, we recommended that cur E75 has the best trade-off between fishery resources exploitation and conservation, and we also proposed the potentials and issues in their implementations.
基金supported by Shanghai Ocean University Graduate School (PhD Dissertation Grant)the National High-tech R&D Program of China (863 Program 2012AA 092303)+3 种基金Project of Shanghai Science and Technology Innovation (12231203900)Industrialization Program of National Development and Reform Commission (2159999)National Key Technologies Research, Development Program of China (2013BAD13B00)Shanghai Universities First-Class Disciplines Project (Fisheries A)
文摘The stock of Bigeye tuna(Thunnus obesus) in the Indian Ocean supports an important international fishery and is considered to be fully exploited. The responsible management agency, the Indian Ocean Tuna Commission(IOTC), does not have an explicit management decision-making framework in place to prevent over-fishing. In this study, we evaluated three harvest control rules, i) constant fishing mortality(CF), from 0.2 to 0.6, ii) constant catch(CC), from 60000 to 140000 t, and iii) constant escapement(CE), from 0.3 to 0.7. The population dynamics simulated by the operating model was based on the most recent stock assessment using Stock Synthesis version Ⅲ(SS3). Three simulation scenarios(low, medium and high productivity) were designed to cover possible uncertainty in the stock assessment and biological parameters. Performances of three harvest control rules were compared on the basis of three management objectives(over 3, 10 and 25 years): i) the probability of maintaining spawning stock biomass above a level that can sustain maximum sustainable yield(MSY) on average, ii) the probability of achieving average catches between 0.8 MSY and 1.0 MSY, and iii) inter-annual variability in catches. The constant escapement strategy(CE=0.5), constant fishing mortality strategy(F=0.4) and constant catch(CC=80000) were the most rational among the respective management scenarios. It is concluded that the short-term annual catch is suggested at 80000 t, and the potential total allowable catch for a stable yield could be set at 120000 t once the stock had recovered successfully. All the strategies considered in this study to achieve a ‘tolerable' balance between resource conservation and utilization have been based around the management objectives of the IOTC.
基金supported by the National Social Science Fundation of China(Grant No.15CGL048)。
文摘This paper puts forward the connotation of enterprise green management and green management performance evaluation,analyzes the characteristics of enterprise green management performance evaluation and decomposes its content.Using the triple performance method,the paper constructs the performance evaluation index system of enterprise green management.Taking BH Petrochemical Co.,Ltd.at the high-efficiency ecological economic zone of the Yellow River Delta as an example,by using analytic hierarchy process(AHP)and Matlab programming,this paper determines the weight of each index in the enterprise green management performance evaluation index system,the fuzzy comprehensive evaluation method is used to evaluate the green management performance evaluation of industrial enterprises.The results show that the performance evaluation index system of enterprise green management constructed by"triple performance method"has important theoretical significance and application value for evaluating and guiding enterprises to strengthen their green management.
文摘This paper analyses the necessity of developing variation information management of construction project. The structure scheme of variation management system has been put forward, which is based on intranet or internet scheme, with the structure of Browser or Server. The system consists of eight modules, which are variation account management, variation application, variation evaluation, variation execution, variation price management, variation report management, variation information query and system maintenance. With this system, remote management and controlling in real time for variation of construction proiect can be carried out.
基金supported by Research Project of Post Graduate Teaching Innovation of Hunan Province in China(JG2015B064)Project of Teaching Innovation of Centre South University of Forestry and Technology(ZNLJG2016-A005)
文摘For training forestry and agricultural mechanical post-graduates＇ innovation ability. This paper studied some problems hindering students improvement, mean value and standard deviation of time management tendency of students were researched. The results showed, graduate enthusiasm should be mobilized, curriculum should be optimized, new teaching methods should be introduced, practice should be strengthened and paid more attention, a strict system of management and evaluation should be established
文摘Background: As one of the most common endocrinal disorders for women at childbearing age, the diagnostic criteria of polycystic ovary syndrome (PCOS) have been defined differently among different international health organizations. Phenotypic heterogeneity of PCOS also brings about difficulties for its diagnosis and management assessment. Therefore, more efficient biomarkers representing the progression of PCOS are expected to be integrated into the monitoring of management process using metabolomic approaches.Methods: In this prospective randomized controlled trial, 117 PCOS patients were enrolled from December 2016 to September 2017. Classical diagnostic parameters, blood glucose, and metabolome were measured in these patients before and at 2 months and 3 months of different medical interventions. The receiver operating characteristic (ROC) curves were built based on multivariate statistical analysis using data at baseline and 3 months’ management, and combinational biomarkers with appreciable sensitivity and specificity were selected, which then validated with data collected at 2 months.Results: A set of metabolites including glutamic acid, aspartic acid, 1-methylnicotinamide, acetylcarnitine, glycerophosphocholine, and oleamide were filtered out with high performance in representing the improvement through 3-month management of PCOS with high sensitivity and specificity in ROC analysis and validation with other two groups showed an appreciable area under the curve over 0.96.Conclusions: The six metabolites were representative of the remission of PCOS through medical intervention, making them a set of potential biomarkers for assessing the outcome of PCOS management.Trial Registration: ClinicalTrials.gov, NCT03264638.
文摘The linchpin of strategy about the Sustainable Development (SD) in Chinese county enforcement area is to accomplish the basic transformation about the mode of economic development from extensive mode to intensive mode. For most counties of China, the overmany population is an element which influences the Sustainable Development. But to achieve the Sustainable Development based on the harmonious development of population, resource, economy and environment, the most important thing is how to carry on its management and evaluation method under the guide of the Tenth Five Year Plan of national economy and the Perspective Target of 2010.Therefore,this paper aims at reforming the traditional judging method focusing on output value Income and establishing a systematic management method and evaluation index system about the sustainable development based on the harmonious growth of population, resource, economy and environment.
基金The workis supported by National Science Foundation of China(60372098) .
文摘Aiming to provide a measurable service Quality of Service （ QoS） evaluating method for service inventory management, this paper proposes a new mobile Service Utility Model （SUM）, considers the service and business layer elements into the service utility influence profile, and proposes an self-adaptive service inventory management algorithm as a QoS control scheme based on SUM. It can be concluded from the simulation result that the service inventory utility can be fully reflected by SUM and the whole system efficiency is greatly increased by using SUM as the adaptive rule.
基金supported by the Fisheries Research and Development Corporation on behalf of the Australian Government through a grant to MDT and DDJ(2016/020)。
文摘Spatial management of fishing effort can be used to avoid catching undesirable size classes for target species,and improve yield-per-recruit for the exploited stock.Adaptive closure management has been proposed as a means to more effectively utilise spatial management,however these management provisions often lack quantitative evaluation which constrains the information available to inform decisions.We demonstrate the use of a spatially and size structured population dynamics model to evaluate the potential impact of spatial management on a multijurisdictional fishery for a highly migratory species(eastern king prawn,Penaeus[Melicertus]plebejus).Under current conditions in the fishery,the overall effect of closures on harvest was estimated to be comparatively minor,regardless of assumptions about how effort or fisher behavior are affected by spatial management.Alternative assumptions about the movement patterns of eastern king prawn had little influence on the impact of closures on overall harvest.However,when effort was increased to historic levels similar to those observed when the closures were implemented,a much greater impact on overall harvest was observed.The approach taken and simulation outcomes are discussed in the context of spatial management for both eastern king prawn,and penaeid fisheries more broadly.
文摘Responsible stock enhancement initiatives require baseline data of wild population demographic conditions that can be used in testing management outcomes.This study provides the first fishery-independent assessment of length-and age-based biological characteristics of exploited populations of Platycephalus fuscus in eastern Australia prior to stock enhancement.Sampling was conducted over seven estuaries spanning seven degrees of latitude and the geographical range of proposed stock enhancements.Populations in all estuaries showed evidence of length and age truncation,especially those subject to commercial fisheries where young individuals of both sexes dominated populations.Maximum longevities were 12 and 11 years for females and males respectively,but few females>5 years and males>3 years were generally sampled.Females dominated populations,and on average,the mean lengths and ages of females were greater than males within each estuary and across all age classes.Sexually dimorphic variation in growth was evident across all estuaries,with females attaining greater maximum lengths than males.Estuary-specific differences in individual growth were not identified.On average,over 50%of females sampled in each estuary were>the minimum legal length(MLL),but the opposite was evident for males.In contrast,over 25%of males in each estuary were>the mean length at maturity(L50),whereas in all but one estuary<13%of the females were>the L50.Stocked male and female P.fuscus should recruit to the fishery in 2 and 3 years,and contribute to the spawning stock in 1.5 and 4.5 years,respectively.This study provides important historical baseline data that can contribute to testing stock enhancement outcomes on populations.
基金This project is financially supported by the Shanghai Ocean University International Center for Marine Sciences and Innovation Program of Shanghai Municipal Education Commission(12YZ134).
文摘Biological reference point(BRP)is one of the essential components in the management strategy evaluation that is used to determine the status of fishery stock and set management regulations.However,as BRPs can be derived from different models and many different BRPs are available,the effectiveness and consistency of different BRPs should be evaluated before being applied to fisheries management.In this study,we used a computation-intensive approach to identify optimal BRPs.We systematically evaluated 1500 combinations of alternative BRPs in managing the bigeye tuna(Thunnus obesus)and yellowfin tuna(Thunnus albacares)fisheries in the Indian Ocean.The effectiveness and consistency of these BRPs were evaluated using four performance measures related to fisheries landing performance and biomass conservation.Monte Carlo simulation was used to evaluate various uncertainties.The results suggest that the proposed computation-intensive approach can be effective in identifying optimal BRPs with respect to a set of defined performance measures.We found that the current maximum sustainable yield(MSY)-based BRP combinations are effective target BRPs to manage the bigeye and yellowfin tuna fisheries with the“linear”harvest control rule(HCR).However,using the“knife-edge”HCR,better BRPs could be found for both the bigeye and yellowfin tuna fisheries management with improved fisheries and conservation performance.The framework developed in this study can be used to identify suitable BRPs based on a set of defined performance measures for other fisheries.
