Evaluation of Water Resources Carrying Capacity in Gansu Section of Yellow River Basin Based on Fuzzy Comprehensive Evaluation Model

As a basic natural resource and strategic economic resource,the development and utilization of water resources is an important issue related to the national economy and people's livelihood.How to scientifically evaluate the water resources carrying capacity is the premise to improve the regional water resources carrying capacity and ensure the regional water security.The Gansu section of the Yellow River basin is an important water conservation and recharge area.Whether the water resources in this area can ensure the normal operation of the ecosystem and whether it can carry the sustainable development of social economy is the key to realize the high-quality development of the Yellow River basin.In this study,from the three dimensions of water consumption per capita,water consumption of 10000 yuan GDP and ecological water use rate,by constructing the evaluation index system and index grading standard of water resources carrying capacity,the fuzzy comprehensive evaluation model was used to evaluate the water resources carrying capacity of Gansu section of the Yellow River Basin,in order to provide theoretical decision-making basis for the comprehensive development,utilization and planning management of water resources in Gansu section of the Yellow River basin and even the whole basin,and help the high-quality development of the Yellow River basin.

Carrying capacity of water environment in public tourism resources based on matter-element model

When water environmental carrying capacity of public resource tourist attraction is studied, the two action subjects of tourists and local residents should be discussed, and comprehensive consideration must be given to the influence of these two on water environment. On the basis of water resource carrying capacity and water quality carrying capacity, water environmental carrying capacity index of public resource tourist attraction was constructed, the model for the water environmental carrying capacity of public resource tourist attraction was established on the basis of matter-element model and analytical hierarchy process. By applying this method, water environmental carrying capacity situation of a certain public resource tourist attraction can be gained, moreover, situations about several aspects of water environmental carrying capacity can be evaluated.

Dynamic evaluation of water resources carrying capacity of the Dianchi Lake Basin in 2005-2015,based on DSPERM framework model and simulated annealing-projection pursuit model

With the intensi fed impact of human activities,most lakes have been severely disturbed and the lake ecosystem has been seriously damaged,which exerted a great impact on the living envi-ronment of human beings in the lake basins.The health of the lake ecosystem has gradually become one of the hot issues in recent years.In this study,the water resources carrying capacity(WRCC)was used to reveal the chain rel ationship between human activities and water environ-ment in the economic dewelopment of the Dianchi Lake Basin in Kunming City of China during 2005-2015.Specifically,we chose 25 ewaluation indicators related to the water environment and socialeconomic activities,classified them into six subsystems,Le,the driwing force subsystem(D),the water resources si tuation and consumption subsystem(S),the water resources pressure subsystem(P),the water environmental situation subsystem(E),the response subsystem(R),and the management subsystem(M),and built a comprehensive assessment system-DSPERM frame-work model.Si mulated annealing-projection pursuit model which reflects the structure or feature of high-dimensional data was adopted to calculate the WRCC of the Dianchi Lake Basin during 2005-2015 by weighting each evaluation indicator and each subsystem of the DSPERM frame work model.The resuls show that the WRCC of the Dlanchi Lake Basin was in level II(medium carying capacity)from 2005 to 2012.Since 2013,the WRCC has been at level II(strong carying capacity),and from 2005 to 2015,it showed a gradual upward trend.The evaluation indicators of each subsystem varied greatly and exhibited different development trends.The indicators of the water resources pressure subsystem had the greatest impact on the WRCC,followed by the in-dicators of the water environmental si tuation subsystem and the water resources situation and consumption subsystem.We recommend that the DSPERM framework model and the simulated anneal ing-projection pursuit model constructed in this work can be used to analyze the dynamic changes of the WRCC over the years.They have the advantages of practicability and feasibilty,and can provide the basis for the scienti fic decision-making and comprehensive management of regional water environment planning.

Estimation of Bounded Populations and Carrying Capacity with the Logistic Model

Estimation of bounded populations and carrying capacity in the presence of a sample frame is considered. Models based on Logistic model are proposed. Like the existing estimators, this estimation technique deals with initial condition and is based on yearly population totals in order to fit in a model within a given period of time in this study. The proposed Logistic model technique has shown to be efficient especially with large data. The empirical study indicated that the Logistic model is efficient and can estimate properly even in the presence of outliers.

Model Modification and Application on Carrying Capacity of Relative Resources

Based on the retrospection of researches on carrying capacity, this article reviewed systematically the research progresses on carrying capacity of relative resources (CCRR). Then the viewpoint was put forward that CCRR is not an appropriate method of appraising the regional sustainability, but a sound way to obtain cognition for coordinating spatial location and flow of population and economy. However, as the most popular computing method of CCRR, the Weighting Linear Sum Model is defective in the random of weight choice and the neglect of matching among different resources. Therefore, this article established the Geometric Model on CCRR based on modifying Weighting Linear Sum Model, which can be used to appraise regions where resources are close matching. Employing the Geometric Model, the article empirically analyzed the population and economic CCRR in Hubei Province from 1978 to 2006. The result indicates that the population in Hubei Province is overloading while the economic carrying capacity is abundant compared to the whole country, and the economic insufficiency restricts the population carrying capacity. In the future, Hubei Province will become one of the core developing zones which are characterized by economic conglomeration.

Managing Tourism Development in the Dutch City of Utrecht using a Linear Programming Model of the Tourist Carrying Capacity

As one part of the Landstad International Metropolitan Area,Utrecht has become known as one of the best tourist destinations in recent years,with the rapid growth of worldwide travel trends.In this paper,through the adaption of the linear programming model,the paper intends to not only quantify the optimum number of visitors to Utrecht but also formulate a number of policy recommendations based on the reconstruction of this optimum.The paper draws the following conclusions:(1) tourist carrying capacity of Utrecht is not yet exceeded;(2) restrictive accommodation policy does not currently seem necessary;(3) the cultural-historical attractions are not yet optimally used;(4) investing in strategic provisions is currently not necessary.And from the conclusion,the paper further puts forward the following suggestions on the city’s tourism development strategy:(1) to identify "tourist flood plains";(2) to encourage the tourist disclosure of these alternatives;(3) to invest even more explicitly in residential tourism and,where possible,curb day tourism;(4) to introduce a new business model.

Response of phytoplankton to multispecies mariculture:a case study on the carrying capacity of shellfish in the Sanggou Bay in China

A muhispecies model for shellfish polycuhure in the Sanggou Bay in China used for large-scale long-line cultivation of the Chinese scallop Chlamysfarreri, the Pacific oyster Crassostrea gigas and the kelp Laminaria japonica is presented. The model includes key physical processes which are the transports of matter at the system boundary, and the main biological process that is the primary production and nutrients release from the bottom. By the model, the seasonal fluctuations of phytoplankton biomass and dissolved inorganic nitrogen（DIN） in 1994 are simulated. Furthermore, if the kelp culture scale is kept constant and the Chinese scallop and the Pacific oyster culture scales are adjusted, virtual shellfish farms are funded and responses of phytoplankton to the largescale shellfish culture are simulated. According to these simulated results, the room limitation, and the hypothesis that shellfish will not grow well if the phytoplankton biomass is less than 8.2 mg/m^3 , the expandable multiple of scallop culture k and that of oyster culture y are determined as k = -0.276 5y ＋4.690 5 and 0.133 3k ＋0.006 6y≤0.667 5, where, k （ or y） is equal to 1, the culture scale of scallop （ or oyster） is 8.8 x 109 individuals （or 66 ha, with a density of 59 ind./m^2 ）, and the kelp culture scale is 3 300 ha with a density of 12 ind./m^2.

Comprehensive Assessment of Water Environment Carrying Capacity of Yunnan Province

Based on the concept and connotation of water environment carrying capacity, taking Yunnan Province as a case, this paper built water environment carrying capacity evaluation system from the perspectives of water resources, water environment carrying capacity and socio-economic development, and applied the index evaluation model to analyze the trends of water environment carrying capacity in Yunnan from 2006 to 2014. The results showed that, during those years, the evaluation value of water environment carrying capacity ranged from 0.23 to 0.46 in Yunnan Province.The minimum value was 0.23 in 2013, the maximum value was 0.46 in 2010. From 2006 to 2014, the evaluation value of water environment carrying capacity was less than 0.5 in general, and the water environment in a fragile state on the whole.

Empirical Research on Carrying Capacity of Human Settlement System in Dalian City, Liaoning Province, China

Using the theories of population carrying capacity and ecological elasticity in other fields for reference, the connotation of regional human settlement system was defined from the viewpoint of the complex relationship among the factors such as regional population, resources, environment and economic and social development in the context of China′s rapid urbanization. Then the concept and characterization methods of the regional human settlement carrying capacity were proposed by means of population scale. Furthermore, a model of carrying capacity-pressure-state-response(CPSR) on regional human settlement system was established by referencing pressure-state-response(PSR) model, and the Catastrophe Theory was introduced to determine the corresponding standards of multi-criteria programming and evaluation. Taking Dalian City, Liaoning Province, China as an example, an empirical analysis on evaluation of human settlement system from 2000 to 2012 was carried out. The results showed that the carrying capacity of human settlement system in Dalian was fluctuating between 9.6 × 106 to 10 × 106 persons with a quantitative stage of the dynamic regulation. During the research period the load index of human settlement system in Dalian dropped from 0.96 to 0.84 with a lower pressure of human settlement system than the national average level. And the emergency response grades of human settlement system in Dalian were kept in grade Ⅱ(orange warning) or grade Ⅲ(yellow warning). Human settlement system of Dalian was in slight security state as a whole, but the load had a tendency of increase in recent years. The related departments should pay close attention to regional human settlement system and take active measures to improve human settlement by both intensity control and total quantity control. By comparison, analysis and discussion, it was considered that the results were basically accordded with the current situations of human settlement in Dalian, and the evaluation results were more reliable, visualized and easily applied in practice. Therefore, the above-mentioned concepts, characterization and evaluation methods of the regional human settlement system and carrying capacity could provide a new thought and method for quantitative evaluation of human settlement.

Ecological Carrying Capacity Prediction of Huainan City Based on GM–BP Neural Network

Evaluation of ecological carrying capacity is an important method of analyzing regional sustainable development, study on ecological carrying capacity is to settle the contradictions between resource and environment, and it is a significant basis for realizing regional sustainable development. This paper, on the basis of the academician Sun Tiehang's "unification of three" for the eco-city construction, established ecological carrying capacity evaluation indexes for the traditional industrial and mining city—Huainan City; and applied GM–BP neural network coupling model for the dynamic evolution and prediction of ecological carrying capacity of Huainan City in the future decade. The results showed that ecological carrying capacity index of Huainan would be 2.13 by 2025, higher than the loadable state 1, so the ecological carrying capacity would keep in the over-loaded level, but the over-loaded degree would be lower than the current. Carrying capacity of arable land, energy and water resources contribute greatly to the improvement of ecological carrying capacity, thus it is imperative to adjust this unreasonable and unsustainable ecological consumption relationship, enhance environmental protection awareness and high-efficiency utilization of resources, and take an energy-saving and intensive development path.

Evaluation on water resources carrying capacity of Changchun-Jilin Region

Based on such principles as sustainable development and ecological cycle, this paper evaluates the water resources carrying capacity(WCC) of Changchun-Jilin region using a population-economy-water resources correlation evaluation model built on the basis of WCC evaluation method as elaborated in the methodology of Functional Zoning of Population Development. Results show that the annual WCC of Changchun-Jilin region is able to support the population there, as a basic balance is struck between population and water resources. The incorporation of WCC into overall urban planning is one of the building blocks for sustainable city development with an advisable size.

Study on Ecological Carrying Capacity of Land in Henan Province

In order to explore the technical methods to improve the ecological carrying capacity of regional land under the premise of limited land use area,an open ecological footprint model is established based on the traditional ecological footprint model.Using the two models,this paper evaluates the ecological carrying capacity of Henan Province in 2017.The results indicate that the ecological productive footprint of cultivated land in Henan Province is much larger than the ecological carrying capacity,but the ecological consumption footprint is lower than the ecological carrying capacity.The open ecological footprint model can clearly distinguish the internal and the external ecological consumption footprint after corrected by the consumption adjustment coefficient and the land-use structure adjustment coefficient.Based on the open ecological footprint model,the ecological carrying capacity evaluation results of Henan Province are more realistic.The comprehensive ecological carrying capacity in Henan Province has a surplus,but there are significant differences among different land use types.The cultivated land has the largest ecological carrying capacity surplus,while the fossil energy land has a larger ecological carrying capacity deficit.In the process of achieving sustainable development,Henan Province should focus on reducing energy consumption and improving the ecological carrying capacity of fossil energy land.The paper concludes that the open ecological footprint model can simulate the ecological carrying capacity under different land use structures and different consumption structures.According to the simulation results,the technical methods to improve the ecological carrying capacity under the premise of limited land use scale can be proposed.The research can provide reference for land use structure adjustment,land use planning and land protection in Henan Province.It can also provide scientific basis for ecological protection and high-quality development of the Yellow River basin.

A Diffusive Predator-Prey Model with Spatially Heterogeneous Carrying Capacity

We study local dynamics of a diffusive predator-prey model in a spatially heterogeneous environment,where intrinsic growth rate of the prey is spatially ho-mogeneous,whereas carrying capacity of the habitat is spatially inhomogeneous.In comparison with the existing predator-prey models,the stability of semi-trivial steady state of this model displays distinct properties.For example,for certain intermediate ranges of the death rate of the predator,the semi-trivial steady state can change its stability at least once as the dispersal rate of the prey varies from small to large,while the stability of the semi-trivial steady state is immune from the dispersal rate of the predator.

基于系统动力学模型的郑州市水资源承载力动态模拟

水资源问题制约着缺水城市的可持续发展,近年来郑州市社会经济高速发展,其水资源有限的现状与用水需求快速增长之间的矛盾愈加凸显。为科学研究郑州市水资源承载力远期发展情况,根据郑州市经济社会现状的水资源供需和发展状况,采用多系统综合的系统动力学方法(System Dynamics,SD),结合水资源、生态、经济社会、水利工程四个子系统,构建郑州市水资源承载力研究的SD模型。将2010-2019年的历史数据与SD方法的模拟数据进行比较,平均误差均小于10%,具有较高的可信度,可用来预测郑州市未来的水资源承载力发展情况。在此基础上,通过设定现状延续、控污节流、开源控污和开源节流4种不同方案,对2020-2030年水资源承载力系数进行动态模拟预测。结果表明:2030年4种方案下的水资源承载力系数分别为1.24、1.18、1.00、0.89,现状延续和控污节流方案下的郑州市水资源承载力随着时间的推移呈现严重超载状态,无法承载郑州市经济社会的快速发展;开源控污方案在预测期内的水资源承载力超载状态会对经济社会发展产生较大阻力。故开源节流方案为最佳方案,水资源承载力系数小于1,在研究期内未出现超载状态,可有利缓解郑州市的缺水状况,促进经济社会的发展。结合4种方案的优点,提出有利于郑州市水资源可持续发展的建议与对策。

汶川震区山洪灾害场次洪水最大携沙量预测模型

汶川地震后,震区产生了大量松散堆积体,受强降水影响产生了破坏性更强的山洪灾害,加剧了灾害的危险性,增加了灾害防治的困难度,研究震区山洪灾害可为评估灾害的风险性及后续的管理提供依据。本研究以66处历史山洪灾害作为样本数据,进行可量算影响因子的相关性分析,揭示山洪灾害的携沙量影响机制,确定流域面积、主沟长度、相对高差、物源量四个影响因子作为主控因子,基于SPSS进行非线性回归分析,建立了基于场次洪水最大携沙量及最大携沙距离的估算模型,并选取了汶川县和都江堰市的共23处山洪水沙灾害数据进行了模型的验证且与其他模型对比。结果表明,本研究建立的模型可靠性好,精度更高。研究成果有助于预测汶川震区潜在的山洪水沙灾害区域,为山洪水沙灾害的风险评估提供依据。

基于陆海统筹的资源环境承载力评价方法探讨

海洋、海岸带蕴含的资源丰富,与人类生存发展息息相关。近年来,随着海洋经济的迅速增长,自然岸线和滨海湿地面积减少、生物多样性降低、典型生态系统受损、近岸海域灾害频发、渔业资源减少等问题日益显现。如何从战略高度提升海洋经济,开发和保护并举,确保海岸带、海洋资源取用合理是新时代的重要课题。陆地和海洋是生态系统不可分割的组成部分,开展陆海统筹的资源环境承载力评价是衡量区域经济发展与生态环境是否协调可持续发展的有效途径。文章系统地梳理了承载力概念的发展历程,对比了常用的海洋资源环境承载力评价方法,初步构建了陆海统筹的资源环境承载力评价指标体系,并提出使用熵值法来确定指标权重,采用状态空间评价模型或TOPSIS模型进行承载力综合评价,可以体现陆地和海洋相互影响、相互制约的关系,并具有较强的可操作性,评价结果可以反映区域资源环境承载力的空间差异或随时间变化情况,能够为海洋和海岸带保护利用提供有效借鉴。

基于PLUS模型的2030年滹沱河流域山区段生态承载力时空格局多情景预测

为探讨滹沱河流域山区段当前及未来不同发展情景下生态承载力的时空变化,应用植被净初级生产力改进的生态足迹模型测算分析了流域2015—2020年生态承载力的时空格局变化,并借助经过精度验证的PLUS模型对2030年区域自然发展、经济发展及生态保护三种发展情景下的生态承载力时空格局进行预测。结果表明:2015—2030年滹沱河流域山区段单位面积生态承载力整体格局变化不大,但内部空间分异明显,整体呈东南及西北区域单位面积生态承载力高,而东北、西南部区域单位面积生态承载力低的特点。2015—2020年区域生态承载力总量由1.0780×10^(6)bhm^(2)增加到1.0796×10^(6)bhm^(2),呈上升趋势;2030年自然发展和经济发展情景下区域生态承载力总量分别为1.0783×10^(6)、1.0782×10^(6)bhm^(2),与2020年相比呈下降趋势,草地向耕地的转移、林地向建设用地的转移是生态承载力下降的主要原因;2030年生态保护情景下生态承载力总量为1.0802×10^(6)bhm^(2),与2020年相比呈上升趋势,耕地向林地、草地转移是区域生态承载力增加的主要原因。各类用地的生态承载力总量由高到低依次为草地>耕地>林地>建设用地>水域,生态保护情景有益于林地、草地生态承载力总量的增加,经济发展情景有益于耕地和建设用地生态承载力总量的增加,水域生态承载力总量在各种发展情景下变化较小。生态保护情景更有利于未来生态承载力的增加,符合区域未来发展方向。严格控制草地向耕地的转变以及林地向建设用地的转变,继续实施退耕还林、还草生态工程,加强区域废弃矿山生态复垦的力度,将会提高区域未来生态承载力,实现区域生态安全及经济、社会、生态的可持续发展。

交口灌区农业水土资源承载力评价及障碍因子诊断

【目的】评价交口灌区农业水土资源承载力及其障碍因子。【方法】以交口灌区为研究对象,构建包括水土资源、社会、经济、生态环境4个准则层的水土资源承载力评价指标体系,采用组合赋权的TOPSIS模型对交口灌区水土资源承载力进行综合评价,采用障碍度模型诊断制约灌区农业水土资源承载力的主要障碍因子。【结果】2016—2020年,交口灌区水土资源承载力呈稳步提升态势,各区、县的水土资源承载力差距逐渐缩小;灌区不同区、县的水土资源承载力水平差异显著,灌区北部承载力水平高于灌区南部,各区、县承载力指数介于0.257~0.621;水土资源和生态环境系统中的单位耕地农药施用量、水土资源匹配系数、单位耕地施肥量、垦殖率、生态环境用水率、水资源开发利用率是制约交口灌区水土资源承载力提升的主要障碍因子。【结论】水土资源和生态环境是影响灌区水土资源承载力的关键要素,灌区应以可持续发展理论为导向,注重农业发展与生态保护并重,综合提升灌区承载力。

基于组合赋权TOPSIS模型的宿州市水资源承载力评价及障碍因子研究

研究区域水资源承载力是发现和解决区域水资源问题的重要途径。针对皖北平原水资源短缺和水环境污染等问题,以宿州市为例,基于主体框架法构建评价指标体系,采用组合赋权的优劣解距离法对宿州市2012—2021年水资源承载力进行了评价,并引入障碍度模型识别全市水资源承载力提升的障碍因素。结果表明:2012—2021年,宿州市水资源承载力状况呈现波动变化的趋势(临界超载—轻度超载—临界超载),全市水资源供需处于紧平衡状态;人均供水量、万元GPD排放COD量、城市污水处理厂日处理能力是阻碍宿州市水资源承载力提升的主要障碍因子。该评价结果及评价方法合理可靠,可为其他城市水资源承载力评价提供有益参考。

基于PSIR的全国林业制造业的生态承载力研究

生态承载力的研究是可持续发展这一国家战略的基础和内涵。选取2005-2021年中国林业制造业生态承载力有关数据,采用PSIR模型选取初始指标,通过内部一致性检验、KMO和Bartlett球形度对初始指标进行筛选,并使用因子分析法和熵值法计算各指标权重。得出逐年评估指数,考察林业制造业生态承载力影响因素随时间的演变轨迹。结果表明:2017年得分0.1418最高,社会经济和产业发展压力对得分影响最大。