Spatial and Temporal Differences of Urban Land Comprehensive Carrying Capacity in Guangxi

The comprehensive carrying capacity of urban land can reflect the re- source level, economic scale, social development and environmental pressure of ur- ban land carrying. The assessment indicator system of urban land comprehensive carrying capacity was constructed from the 4 aspects of resource, economy, society, environment, and principal component analysis and cluster analysis were used to evaluate the urban land comprehensive carrying capacity of Guangxi and the 14 cities in 2005-2014, and analyzed its spatial and temporal characteristics as well as the driving forces, with the aim to provide references for improving the urban land comprehensive carrying capacity. The results showed that, the overall urban land comprehensive carrying capacity in Guangxi increased in 2005-2014, and there were significant differences in the land comprehensive carrying capacities among the cities in Guangxi in 2005-2014, in which Liuzhou, Guilin, Nanning belonged to the regions with the highest carrying capacity, while Beihai, Yulin, Wutong belonged to the regions with high carrying capacity, and the carrying capacities of the other cities changed with the changes of time. The economic development degree was an important factor influencing urban land comprehensive carrying capacity, but could not directly represent the urban land comprehensive carrying capacity level.

Assessment of Land Comprehensive Carrying Capacity in Lin'an City

According to regional characteristics and the actual situation in Lin ’an City, an evaluation index system of land comprehensive carrying capacity composed of three support subsystems （eco-environment, social and economic carrying capaci-ties） containing 22 evaluation indexes was established to evaluate the comprehen-sive carrying capacity of land resource in Lin’an City during 2005-2012. Meanwhile, based on the target data of overal land use plan, the level of land comprehensive carrying capacity was predicted at the end of the plan period （2020） .The results showed that land comprehensive carrying capacity had a significant growth in Lin ’an from 2005 to 2012, and the development trend was basical y sustainable. The sub-systems also had been greatly improved, in which the constant improvement of ec-ological environment carrying capacity made the largest contribution to the constant raising of land comprehensive carrying capacity. The degree of coordination between the systems was poor, in which eco-environment carrying capacity had the maxi-mum growth, far more than the social and economic carrying capacities. According to the land comprehensive carrying capacity in 2020, utilization of land resources in Lin＆#39;an city can achieve sustainable development in general. Final y, proposals of im-proving comprehensive carrying capacity were put forward in terms of the enhance-ment of eco-environment protection, accelerating economic development and policy guidance.

Performance Evaluation of Urban Comprehensive Carrying Capacity of Harbin, Heilongjiang Province in China

Urban comprehensive carrying capacity is an important guarantee and external representation of regional sustainable development. Based on urban comprehensive carrying capacity, this paper constructed a performance evaluation index system of urban comprehensive carrying capacity, and used entropy method, urban comprehensive carrying capacity measurement model and urban sustainable development model to measure spatial and temporal comprehensive carrying capacity of Harbin City in Heilongjiang Province from 2012 to 2017. The results show that: 1) index weight analysis suggested the regional development mode in Harbin still followed an epitaxial development mode, which pursued the expansion of scale and the growth of total amount of regional development, neglecting the effective utilization of resources and the improvement of structural benefits. 2) In the pressure system, the index of resource support has dropped sharply. The index of environmental capacity and social progress has risen circuitously, while the degree of agglomeration and the value of transportation facilities have risen steadily;in the pressure system, the index of population development and economic growth tended to fluctuate, while energy consumption and environmental pollution showed a more synchronous change in characteristics, and the livable demand remained at a high level. 3) The carrying capacity index of resources and environment in Harbin has been declining, and the acquired carrying capacity index fluctuated. The long-term regional development model has severely impaired the carrying capacity of resources and environment. 4) The comprehensive carrying capacity of Harbin has clear spatial differentiation characteristics. Finally, the paper proposes that location conditions, economic development level, government regulation, and science and technology are the main factors influencing the spatial differentiation of urban comprehensive carrying capacity.

Fuzzy Comprehensive Evaluation Model for Water Resources Carrying Capacity in Tarim River Basin,Xinjiang,China

This paper explores the method of comprehensive evaluation of water resources carrying capacity and sets up an evaluation model applying the fuzzy comprehensive evaluation method. Based on the data of nature,society,economics and water resources of the Tarim River Basin in 2002,we evaluated the water resources carrying capacity of the basin by means of the model. The results show that the comprehensive grades are 0.438 and 0.454 for Aksu and Kashi prefectures respectively,where the current water resources exploitation and utilization has reached a relative high degree and there is only a very limited water carrying capacity,0.620 for Kizilsu Kirgiz Autonomous Prefecture,where water resources carrying capacity is much higher,and in between for Hotan Prefecture and Bayingolin Mongo-lian Autonomous Prefecture. As a whole,the comprehensive grade of the Tarim River Basin is 0.508 and the current water resources exploitation and utilization has reached a relative high degree. Thus,we suggest that the integrated management of the water resources in the basin should be strengthened in order to utilize water resources scientifically and sustainably.

Comprehensive Measurement for Carrying Capacity of Resources and Environment of City Clusters in Central China

Studying the carrying capacity of resources and environment of city clusters in the central China has important practical guidance significance for promoting the healthy, sustainable and stable development of this region. According to their influencing factors and reciprocity mechanism, using system dynamics approaches, this paper built a SD model for measuring the carrying capacity of resources and environment of the city clusters in the central China, and through setting different development models, the comprehensive measurement analysis on the carrying capacity was carried out. The results show that the model of promoting socio-economic development under the protection of resources and environment is the optimal model for promoting the harmony development of resources, environment, society and economy in the city clusters. According to this model, the optimum population scale of the city clusters in 2020 is 42.80×106 persons, and the moderate economic development scale is 22.055×1012 yuan (RMB). In 1996-2020, the carrying capacity of resources and environment in the city clusters took on obvious phase-change characteristics. During the studied period, it is basically at the initial development stage, and will come through the development process from slow development to speedup development.

The comprehensive evaluation on resource environmental bearing capacity of central cities in the Yellow River Delta-A case study on Dongying City

Dongying City, which is the most important central city in the Yellow River Delta, is located in the estuary of the Yellow River. With a short land formation time, ecological environment is very weak in this area. To realize the sustainable economic development of the Yellow River Delta, resource environment and resource environmental bearing capacity(REBC) must be improved. This study builds assessment system of regional REBC through resource and economic characteristics in Yellow River Delta and uses principal component analysis(PCA) method to evaluate REBC of five counties and districts in Dongying City in 2011-2015 on the dimensions of time and space. Results show that, on the time dimension, Guangrao County is ranked first, Dongying district second for four years and Hekou and Kenli districts with lower ranks in 2012-2015, indicating that more attention needs to be paid to REBC of Hekou and Dongying districts and these two districts should be included into key monitoring areas. From space scale, REBC in five counties and districts has been gradually improving. In order to further develop REBC in Dongying City, measures such as intensifying protection of urban ecological environment and developing circular economy, etc. should be implemented.

Evaluation of water resources carrying capacity of Gonghe basin based on fuzzy comprehensive evaluation method

Gonghe Basin belongs to arid and semi-arid climatic zone, where water resource is relatively scarce and desertification is serious, so it is necessary to find out water resources carrying capacity. By using fuzzy comprehensive evaluation method, the assessment on water resources carrying capacity in Gonghe Basin was conducted: Water resource carrying capacity of Gonghe County is less, while that of Guinan County and Chaka Town of Wulan County are greater; water resources of Gonghe Basin could sustain cultivated land of 652.6 thousand acres and grassland of 2 368.6 thousand acres respectively in 2020, water resources of Gonghe Basin could sustain cultivated land of 948.2 thousand acres and grassland of 2 247.6 thousand acres respectively in 2030.

Evaluation of Comprehensive Agricultural Production Capacity Based on Factor Analysis:A Case Study of Hunan Province

Based on the basic connotation of comprehensive agricultural production capacity,this article establishes the comprehensive agricultural production capacity indicator system on the basis of statistics. This indicator system consists of 5 parts ( input scale of factors,output scale of factors,output rate of factors,ability to resist disaster and ensure production,and modern operation level) and 14 specific indicators. Based on factor analysis method,we use this indicator system to conduct systematic empirical analysis of the level of comprehensive agricultural production capacity in 14 cities and prefectures of Hunan Province. The results show that although the overall level of comprehensive agricultural production capacity in Hunan Province tends to grow continuously and steadily,there are significant inter-regional differences in the level of comprehensive agricultural production capacity; in terms of the level of comprehensive agricultural production capacity,there is great room for improvement. Finally the following policy recommendations are put forward: strengthening balanced regional development and improving the overall level of comprehensive agricultural production capacity; strengthening the building of land carrying capacity; strengthening the building of agricultural ecological balance; strengthening the building of the scientific and technological support capacity.

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.

Text Difficulty,Working Memory Capacity and Mind Wandering During Chinese EFL Learners’Reading

This experimental study investigated how text difficulty and different working memory capacity(WMC)affected Chinese EFL learners’reading comprehension and their tendency to engage in task-unrelated thoughts,that is,mind wandering(MW),in the course of reading.Sixty first-year university non-English majors participated in the study.A two-factor mixed experimental design of 2(text difficulty:difficult and simple)×2(WMC:high/large and low/small)was employed.Results revealed that 1)the main and interaction effects of WMC and text difficulty on voluntary MW were significant,whereas those on involuntary MW were not;2)while reading the easy texts,the involuntary MW of high-WMC individuals was less frequent than that of low-WMC ones,whereas while reading the difficult ones,the direct relationship between WMC and involuntary MW was not found;and that 3)high-WMC individuals had a lower overall rate of MW and better reading performance than low-WMC individuals did,but with increasing text difficulty,their rates of overall MW and voluntary MW were getting higher and higher,and the reading performance was getting lower and lower.These results lend support to WM theory and have pedagogical implications for the instruction of L2 reading.

Integrating multisource RS data and GIS techniques to assist the evaluation of resource-environment carrying capacity in karst mountainous area

The karst mountainous area is an ecologically fragile region with prominent humanland contradictions.The resource-environment carrying capacity(RECC)of this region needs to be further clarified.The development of remote sensing(RS)and geographic information system(GIS)provides data sources and processing platform for RECC monitoring.This study analyzed and established the evaluation index system of RECC by considering particularity in the karst mountainous area of Southwest China;processed multisource RS data(Sentinel-2,Aster-DEM and Landsat-8)to extract the spatial distributions of nine key indexes by GIS techniques(information classification,overlay analysis and raster calculation);proposed the methods of index integration and fuzzy comprehensive evaluation of the RECC by GIS;and took a typical area,Guangnan County in Yunnan Province of China,as an experimental area to explore the effectiveness of the indexes and methods.The results showed that:(1)The important indexes affecting the RECC of karst mountainous area are water resources,tourism resources,position resources,geographical environment and soil erosion environment.(2)Data on cultivated land,construction land,minerals,transportation,water conservancy,ecosystem services,topography,soil erosion and rocky desertification can be obtained from RS data.GIS techniques integrate the information into the RECC results.The data extraction and processing methods are feasible on evaluating RECC.(3)The RECC of Guangnan County was in the mid-carrying level in 2018.The midcarrying and low-carrying levels were the main types,accounting for more than 80.00%of the total study area.The areas with high carrying capacity were mainly distributed in the northern regions of the northwest-southeast line of the county,and other areas have a low carrying capacity comparatively.The coordination between regional resource-environment status and socioeconomic development is the key to improve RECC.This study explores the evaluation index system of RECC in karst mountainous area and the application of multisource RS data and GIS techniques in the comprehensive evaluation.The methods can be applied in related fields to provide suggestions for data/information extraction and integration,and sustainable development.

The Progress of Resources and Environment Carrying Capacity: from Single-factor Carrying Capacity Research to Comprehensive Research

As a concept to describe development restrictions,resources and environment carrying capacity（RECC）research has developed over more than 100 years since it was first proposed at the beginning of the 20th century.It is now regarded as a significant factor in evaluating the level of cooperation between regional population,resources,and environment;and it is currently used as an effective and operational tool to guide regional sustainable development.This article first reviews the origin of RECC and its early headway.It then reviews the historical development of RECC from single factors,such as land resources carrying capacity,water resources carrying capacity and environmental carrying capacity（environmental capacity）,to more comprehensive research,such as comprehensive evaluation,emergy analysis,and ecological footprint analysis.In general,it appears that comprehensive research will become increasingly important in RECC research.However,there are several deficiencies in the current state of comprehensive research.Firstly,comprehensive RECC research lacks a common measurement standard,though some scholars have attempted to create one.Secondly,the RECC evaluation of open systems and dynamic studies should be strengthened.Thirdly,more attention should be paid to standardization,digitalization,and systematization to promote the applicability of RECC research to national practical demands.

Short-term Memory Training in Listening Comprehension

Listening comprehension is an important part in most of the English examinations because of the commonly using of listening in communication. It is a common phenomena that most of the students have problems in this part because of the limit?ed capacity of short-term memory. In this essay, we will talk about the relationship between the short-term memory and listen?ing comprehension, and try to find the way to train the short-term memory to improve this part.

基于灰色关联度分析挺水植物模拟生活污水的净化能力

以17种挺水植物为研究对象,对挺水植物进行驯化处理,随后移植在模拟生活污水中培养,在不同的时间段内采集水质,并对水质中的总氮、总磷、氨氮和化学需氧量以及pH进行监测,采用灰色关联度分析评价挺水植物的综合净化水质的能力。结果表明,不同的挺水植物对单个水质指标的去污能力差异较大;灰色关联度分析17种挺水植物综合去污能力优等的有3种,分别是旱伞草、紫芋和灯芯草;综合去污能力良好的有6种,分别是海寿花、水葱、溪荪、水生美人蕉、花叶芦竹、再力花;综合去污能力中等的有5种,分别是香蒲、水芹、慈姑、纸莎草、泽泻;综合去污能力较低的有3种,分别是千屈菜、黄菖蒲、菰。初步筛查出9种挺水植物具有良好的综合去污效果,试验结果可为后续小微湿地水生植物示范与推广提供基础数据。

面向起重机结构承载能力评估的数字孪生系统构建方法

针对当前起重机本质安全所面临的监测力度差、能力指标单一、数据利用率不高导致承载能力评估效率低、评估结果不够全面的问题,本着“虚实互控-互调-互补”的思想,提出面向起重机结构承载能力评估的数字孪生系统构建方法。从设备服役场景出发,结合数字孪生五维模型,设计起重机结构承载能力数字孪生框架;以多指标下的结构承载能力动态综合评估方法为支撑,围绕虚实映射、数据交互与服务交互,分层分级阐述结构承载能力数字孪生系统构建方法;从模块内聚,功能集成的角度,搭建数字孪生系统平台。以YDC20/30轻小型移动式起重机为例,验证了所提方法及系统的有效性,为及时精准判断起重机服役过程中的安全性提供了一种新途径、新策略。

京津冀城市群综合承灾能力时空异质性研究

基于2010—2020年京津冀城市群13个城市的调查数据,应用Kernel密度估计方法、空间自相关模型及Dagum基尼系数,分析不同时期京津冀城市群综合承灾能力时空动态演进分布格局及地区差异。结果表明:(1)在时间维度,2010—2020年京津冀城市群综合承灾能力总体呈现逐渐上升趋势,但京津冀城市群各市之间的承灾能力水平差距逐渐增大,区域整体呈现非均衡特征;(2)在空间维度,2010—2020年京津冀城市群综合承灾能力在空间分布上关联度较低,不存在显著的集聚或分散特征,但有局部地区产生聚集特点,属于“高-高”“低-低”空间聚集型城市较多,在此期间京津冀城市群综合承灾能力呈现空间集聚与空间分异并存;(3)京津冀城市群综合承灾能力的总体差异呈现上升趋势,北京-河北地区间差异最大,地区间差异是总体差异的主要来源。掌握京津冀城市群综合承灾能力的时空分布变化规律,并制订相应的防灾策略是京津冀城市群有效应对外部冲击以及实现京津冀地区协同与高质量发展国家战略的重要支撑。

中国南北方植物对土壤加固机制的差异性

为深入分析植物对土壤加固的影响效益和机制,该研究选取重庆缙云山地区和陕西延安黄土丘陵区种植一年的乔木(火炬树、榆树)和灌木(荆条、酸枣),测定其根系形态、力学参数和土壤的抗剪强度,通过RBMw模型计算根系固土效益,综合评估不同植物的固土效能和贡献度。结果表明:2地种植的物种平均根直径的差异不显著(P>0.05),重庆种植的乔木(火炬树、榆树)的根长、分叉数和根尖数显著高于延安,灌木未出现显著差异(P<0.05)。根系的抗拉强度与直径都符合负幂函数关系,其中平均抗拉强度最大的为荆条。除荆条外,同种植物根系的抗拉强度并未因不同地区的种植产生显著差异。4个植物种根系的固土效率为0.65~4.12 kPa,各物种间存在显著差异(P<0.05)。重庆2种乔木种植下的根土复合体有效黏聚力高于裸地(约10%),灌木种植下则普遍略低于裸地。除酸枣外,种植于重庆的4种植物的根系固土作用和效率都显著的高于延安(P<0.05)。研究结果可为不同地区固土护坡的树种选择提供理论依据。

农村集体产权制度改革综合评价及障碍因子分析

基于改革政策目标,从产权能力完善、集体经济发展和农民权益保障三个方面,运用熵权TOPSIS法和障碍度模型,对中国30个省(区、市)2014—2021年的农村集体产权制度改革进行综合评价和障碍因子分析。研究发现:中国农村集体产权制度改革水平总体呈平稳上升趋势,区域间呈现“东高西低”的特征,各地区改革水平的差距呈逐步缩小态势;各省(区、市)农村集体产权制度改革的主要障碍因子是农业机械化水平、家庭农场发展水平、农村市场化程度、集体经营收入水平、集体经济组织管理能力和农村居民财产性收入占比,基本属于集体经济发展维度,表明农村集体经济发展水平与改革规划目标仍有差距,还需进一步提升集体产权改革的经济效能。

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。

河南省联合体试验小麦品种综合性状分析与评价

主要农作物品种审定联合体试验是当前我国农业形势下拓宽作物品种审定试验渠道重点推进的新措施,为深入了解河南省小麦联合体试验容量、掌握其品种农艺性状和品质性状概况,以近3 a(2021—2023年)河南省审定通过的小麦品种为对象,将联合体试验品种与省统一试验品种进行对比分析和评价。结果表明,2021—2023年河南省通过审定的小麦品种合计355个,其中,联合体试验品种187个。联合体试验容量呈上升趋势,品种数量占比由2021年的48.3%上升到2023年的61.2%;试验组别单一,主要为冬水组。冬水组小麦中,申请者独立申请品种时,联合体试验品种中高校和科研院所占比较省统一试验高,个人申请则更倾向于参加省统一试验。联合体试验小麦农艺性状与省统一试验相比差异前期大后期小,7个农艺性状中2021年有5个性状差异显著或极显著、2023年有2个性状差异显著;品质性状差异相对较小,但也表现出前期大后期小的规律,7个品质性状中2021年有2个性状差异显著、2023年均不显著。联合体试验品种的农艺性状、品质性状的变异系数及多样性整体上均大于省统一试验。利用主成分分析将14个农艺性状和品质性状转化为7个主成分,其反映了81.51%的原始信息。基于主成分分析的评价结果表明,综合评价得分排名前50位的品种中,联合体试验小麦品种在其全部品种中占比较小,2021、2023年分别有5、14个,分别占当年全部联合体试验品种数量的9.3%、17.9%;省统一试验小麦品种在其全部品种中占比较大,2021、2023年分别有4、5个,分别占当年全部省统一试验品种数量的19.0%、35.7%。综上,河南省小麦联合体试验容量在不断提升,农艺性状和品质性状离散程度较大,品种综合评价得分与省统一试验差距缩小,相关部门未来可根据市场调整优化试验组别,聚焦联合体试验通道问题,推进联合体试验高质量发展。