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1.
气候是影响区域宜居性的一个重要自然因素。人居环境气候适宜性深刻影响着区域人口分布和社会经济发展。西藏地区是气候变化的敏感地区,近年来随着全球气候变化的影响,该地区的气候适宜性也发生了显著变化。本文基于多年平均气候数据计算了西藏地区的温湿指数,定量分析了人口分布与温湿指数之间的关系;在此基础之上,确定了西藏地区气候适宜性分区标准;最后评价了西藏地区的人居环境气候适宜性。结果表明:西藏东南部地区年均温度相对较高,人口分布相对密集;年均相对湿度整体上呈现出由南向北逐渐降低的趋势。西藏气候适宜地区(包括高度适宜地区、比较适宜地区和一般适宜地区)面积占比仅为7.90%,人口数量比重超过40%。气候临界适宜地区面积占比为37.81%,人口占比为48.24%。气候不适宜地区广泛分布于各地市,面积占比为54.29%,人口占比为11.33%。本文的研究结果可为指导西藏地区人口的合理分布以及优化国土空间规划提供参考。  相似文献   

2.
随着我国农业生态文明建设的推进,农业生态安全也日益受到重视。如何确保农业生态的安全,已经成为不少学者关注的话题。湖北省作为我国重要的农业大省、全国粮食生产基地,确保其农业生态安全对全国粮食安全与农业可持续发展具有重要意义。本文首先运用层次分析法(AHP)与"压力—状态—响应"(PSR)模型构建湖北省农业生态安全评价指标体系与安全等级,接着将2015年全国农业生态安全平均值作为基数,对湖北省农业生态安全进行评价,发现其安全度从2005年的0.90150提升到了2015年的0.97716,提高了0.07566,但没有达到全国的平均值。这说明湖北省农业生态安全虽然得到改善,但是压力还很大,安全度还有待提升。特别是人均水资源量、人口密度、单位面积耕地农药负荷、森林覆盖率、草地退化率、年均降水量等部分指标还呈现恶化趋势。基于此,我们对影响湖北省农业生态安全的因素进行了分析,发现人口布局不合理、农业不当的生产行为、农业自然灾害、农业生态技术的缺失是主要因素。最后,笔者从影响因素层面提出了提升湖北省农业生态安全度的对策建议,希望以此来改善农业生态安全。  相似文献   

3.
在对陕西省农业土地资源适宜性评价研究的基础上,对农业土地资源适宜性评价的理论与方法等问题进行了较深入的讨论。拓宽和深化了土地资源适宜性评价的理论与方法,提高了土地资源适宜性的精度和效率。  相似文献   

4.
本文基于预期效用假设提出了可结合竞争学习算法(CLG–LUSA)的新方法,即土地利用适宜性分析的GIS模型。该模型使用了Kohonen的自组织映射法和线性矢量化法来实现多选项的综合排序。该模型还利用决策者的优选位置和环境数据,来构造一个分支决策属性空间。决策和不确定性映射来自于该分支算法。使用该模型算法的一个例子就是在古巴市选择椰子最合适的生长环境。结果表明,CLG–LUSA模型能够提供决策过程中关键环节的精确视觉反馈,从而制定最适合个人或群体决策支持方法。  相似文献   

5.
Precipitation heterogeneity has a nontrivial influence on human life. Many studies have analyzed precipitation heterogeneity but none have proposed a systematic graded index for its evaluation, and therefore, its true characteristics have not been expressed. After comparisons of various methods, the precipitation concentration degree(PCD) method was selected to study precipitation heterogeneity. In addition to the PCD, normal distribution functions, cumulative frequencies, and percentiles were used to establish a graded index for evaluating precipitation heterogeneity. A comprehensive evaluation of precipitation heterogeneity was performed, and its spatiotemporal variation in China from 1960 to 2013 was analyzed. The results indicated that(1) seven categories of precipitation heterogeneity were identified(high centralization, moderate centralization, mild centralization, normal, mild dispersion, moderate dispersion, and high dispersion) and(2) during the study period, the precipitation in more parts of China tended to be normal or dispersed, which is beneficial to human activities.  相似文献   

6.
中国土地适宜性评价研究进展   总被引:19,自引:1,他引:19  
长期以来, 土地适宜性评价一直在土地规划利用中起着基础性作用。近十几年, 农业土地 适宜性评价持续深入开展, 城市用地、旅游用地、土地整理复垦以及其他用地的土地适宜性评价 日渐增多; 基于此, 土地适宜性评价的理论思想得到了进一步的丰富, 景观生态学被引入土地适 宜性评价, 可持续利用观深入人心; 土地适宜性评价在方法上也有新的发展, GIS 在土地适宜性 评价中得到广泛的应用, 这使得土地适宜性评价更为灵活、科学。  相似文献   

7.
本文采用模糊综合评价方法进行了开封市郊区的土地适宜性评价,并就土地适宜性评价基础、模糊综合评价模型等问题作了探讨。  相似文献   

8.
海南岛土地生态适宜性评价   总被引:19,自引:1,他引:19  
以海南岛为例,在区域层面上选择高度、地形坡度、土地覆被等影响工业用地的关键因子,构建工业用地的生态适宜程度评价模型,并在G IS技术支持下进行工业用地生态经济适宜性评价,为将来区域工业开发区及重点工业项目布局提供依据。结果表明:海南工业用地生态适宜性呈现出由中部山地向四周逐渐增强,限制利用区占25%,不适宜利用区占28%,基本适宜区占41%,优先利用区占5%。其中优先利用区主要分布在西部和北部沿海地带,海口、儋州和东方及其连线一带应成为海南省未来工业用地布局的重点区域。  相似文献   

9.
Strategic transformation of regionalization for agricultural comprehensive development(ACD) was presented by the Ministry of Finance of the People's Republic of China(MOF) in 2014. The regionalization is the premise and basis of the sustainable development and improved competitiveness for agriculture. Based on the environmental resources related to agriculture, such as cropland, climate, water resources, terrain, geomorphology, patterns of the ACD projects, distribution of ecological planning, etc., we devised 13 indices using the geographic comprehensive regionalization method. The indices took into account a combination of dynamic and static, qualitative and quantitative, as well as agricultural and ecological factors. The strategic transformation of regionalization for the ACD in Ningxia Hui Autonomous Region of China was performed; seven types were included: prioritized regions, prioritized and restricted regions, protected regions, protected and restricted regions, restricted and prioritized regions, restricted and protected regions, and restricted regions. A further 24 subtypes were used based on locations and ecological zones. The regionalization results showed that prioritized regions were mainly in northern Ningxia, the most suitable area for agriculture. The protected and restricted regions were in central and southern Ningxia. In the central part, drought was the limiting factor for agriculture, and water conservation projects there should be supported. The ecological environment is fragile in southern Ningxia, so there is a need for ecologically sound agriculture to be developed in this region. Such regionaliza-tion could achieve two goals, namely agricultural conservation and eco-environmental protection. It was performed following the requirement for scientific regionalization to include three types of regions(prioritized regions, protected regions, and restricted regions), and was applied at the township scale in a provincial or autonomous region for the first time. The results provide both guidance for the strategic transformation of the ACD in Ningxia, and a reference for similar work in other provinces.  相似文献   

10.
正Land is critical to society by providing foods,fuel,fibers and many other ecosystem services that support production functions,regulate risks of natural hazards,or provide cultural and spiritual services(Verburg et al.,2013).By using the land,human have transformed a large proportion of the planet’s land surface.These land use activities have enormous conse-  相似文献   

11.
矿区废弃土地资源适宜性评价   总被引:32,自引:1,他引:32  
随着采矿业的发展,我国矿区土地资源破坏相当严重,同时废弃土地资源的复垦利用率又非常低(约10%),矿区废弃土地复垦研究工作非常迫切。开展全国矿区废弃土地的适宜性评价研究是其复垦研究的基础,可为其它相关研究提供实时指导。本文正是根据这种需要,通过实地调查研究,运用一定的原则与依据,将矿区废弃土地资源划分为5类25个亚类,均对每一亚类,作出了相应的适宜性评价,同时还提出了具体的开发利用途径。为矿区废弃土地复垦在技术上的可行性作出了科学的评价,为废弃土地资源的复垦提出有效的开发利用途径,从而为提高土地生产力,缓解土地资源紧缺的矛盾,改善矿区生态环境质量提供有效的政策与技术参考。  相似文献   

12.
在对陕西省农业土地资源适宜性评价研究的基础上,对农业土地资源适宜性评价的理论与方法等问题进行了较深入的讨论。拓宽和深化了土地资源适宜性评价的理论与方法,提高了土地资源适宜性的精度和效率。  相似文献   

13.
为了给临河区土地利用总体规划调整完善提供依据,本文运用ArcGIS技术,在综合分析临河区不同类型土地的自然经济条件的基础上,全面分析临河区宜耕地类和宜林地类的适宜性程度和适宜性等级,为土地利用总体规划调整完善提供依据。  相似文献   

14.
We analyzed the spatial local accuracy of land cover(LC) datasets for the Qiangtang Plateau, High Asia, incorporating 923 field sampling points and seven LC compilations including the International Geosphere Biosphere Programme Data and Information System(IGBPDIS), Global Land cover mapping at 30 m resolution(GlobeLand30), MODIS Land Cover Type product(MCD12 Q1), Climate Change Initiative Land Cover(CCI-LC), Global Land Cover 2000(GLC2000), University of Maryland(UMD), and GlobCover 2009(GlobCover). We initially compared resultant similarities and differences in both area and spatial patterns and analyzed inherent relationships with data sources. We then applied a geographically weighted regression(GWR) approach to predict local accuracy variation. The results of this study reveal that distinct differences, even inverse time series trends, in LC data between CCI-LC and MCD12 Q1 were present between 2001 and 2015, with the exception of category areal discordance between the seven datasets. We also show a series of evident discrepancies amongst the LC datasets sampled here in terms of spatial patterns, that is, high spatial congruence is mainly seen in the homogeneous southeastern region of the study area while a low degree of spatial congruence is widely distributed across heterogeneous northwestern and northeastern regions. The overall combined spatial accuracy of the seven LC datasets considered here is less than 70%, and the GlobeLand30 and CCI-LC datasets exhibit higher local accuracy than their counterparts, yielding maximum overall accuracy(OA) values of 77.39% and 61.43%, respectively. Finally, 5.63% of this area is characterized by both high assessment and accuracy(HH) values, mainly located in central and eastern regions of the Qiangtang Plateau, while most low accuracy regions are found in northern, northeastern, and western regions.  相似文献   

15.
内蒙古是我国北方重要的生态屏障区,在区域生态系统防风固沙中发挥了重要的作用。本研究基于RWEQ模型模拟了内蒙古2010年和2015年生态系统防风固沙物质量,通过恢复成本法估算了其价值量,分析了内蒙古各盟市以及各生态系统防风固沙物质量和价值量变化的空间格局。结果表明2015年内蒙古防风固沙物质量和价值量总量分别为73.87亿t和738.66亿元,相比于2010年共减少了4.61亿t和46.16亿元。在各盟市中,锡林郭勒盟防风固沙总量最高,2015年达18.65亿t,乌海市最少,呼伦贝尔市防风固沙总量增长幅度最大,达4.37亿t;在各生态系统中草地生态系统防风固沙总量最高,占比在55%以上,但总量降低了1.05亿t,森林生态系统防风固沙增长量最高,达0.19亿t。结合生态系统变化及造林实施情况分析,发现造林等工程的投入实施通过增加森林面积、提升森林质量等有效增加了防风固沙物质量,但不合理的土地利用导致沙漠化土地的增加造成了内蒙古防风固沙量的显著降低。  相似文献   

16.
The core objective of rural vitalization is to systemically establish a coupling pattern of various rural development elements including population, land and industry. As one of the prerequisites, land resources is required to be optimally allocated via land consolidation. Consequently, land consolidation contributes greatly to population agglomeration, industrial development and resources support under the context of combating rural decline. Based on the key elements affecting rural development, this paper elaborates the connotation of rural vitalization and land consolidation in the new era as well as their relationships. Furthermore, the paper analyzes the alternative paths for achieving rural vitalization via land consolidation, and discusses the future directions of land consolidation and rural vitalization. The conclusions are drawn as follows:(1) To cope with the loss and decline of the intrinsic elements in rural areas, rural vitalization is a development strategy aimed at realizing economic, political, cultural and ecological rejuvenation in rural area by reshaping socio-economic morphology and spatial pattern in rural territory.(2) From the perspective of rural vitalization, land consolidation is endowed with new connotation, which should not only target at activating the key elements of rural development, but also place emphasis on coordinating material space and spirit core as well as integrating the restructuring of the physical space and the rural governance system.(3) Land consolidation should be compatible with regional natural conditions and the current stage of socio-economic development. According to the principle of regional planning and classification strategy, the appropriate models and paths should be adopted to promote the benign interactions of population, land and industry based on engineering techniques and ecological means.(4) Under the background of national strategy of rural vitalization, it is necessary to reshape the value orientation of land consolidation based on a scientific understanding of urban-rural relations and rural territorial functions, coordinate land consolidation planning and rural vitalization planning under the unified spatial planning system, and explore the new model combining land consolidation and multifunctional agriculture.  相似文献   

17.
Land use intensity quantifies the impacts of human activities on natural ecosystems, which have become the major driver of global environmental change, and thus it serves as an essential measurement for assessing land use sustainability. To date, land-change studies have mainly focused on changes in land cover and their effects on ecological processes, whereas land use intensity has not yet received the attention it deserves and for which spatially-explicit representation studies have only just begun. In this paper, according to the degree and reversibility of surface disturbance by human activities, there are four main classes of land use intensity: artificial land, semi-artificial land, semi-natural land, and natural land. These were further divided into 22 subclasses based on key indicators, such as human population density and the cropping intensity. Land use intensity map of China at a 1-km spatial resolution was obtained based on satellite images and statistical data. The area proportions of artificial land, semi-artificial land, semi-natural land, and natural land were 0.71%, 19.36%, 58.93%, and 21%, respectively. Human and economic carrying capacity increased with the increase of land use intensity. Artificial land supports 24.58% and 35.62% of the total population and GDP, using only 0.71% of the total land, while semi-artificial land supported 58.24% and 49.61% of human population and GDP with 19.36% of China's total land area.  相似文献   

18.
In this paper, we compared the concept of agricultural drought and its relationship with other types of droughts and reviewed the progress of research on agricultural drought monitoring indices on the basis of station data and remote sensing. Applicability and limitations of different drought monitoring indices were also compared. Meanwhile, development history and the latest progress in agricultural drought monitoring were evaluated through statistics and document comparison, suggesting a transformation in agricultural drought monitoring from traditional single meteorological monitoring indices to meteorology and remote sensing-integrated monitoring indices. Finally, an analysis of current challenges in agricultural drought monitoring revealed future research prospects for agricultural drought monitoring, such as investigating the mechanism underlying agricultural drought, identifying factors that influence agricultural drought, developing multi-spatiotemporal scales models for agricultural drought monitoring, coupling qualitative and quantitative agricultural drought evaluation models, and improving the application levels of remote sensing data in agricultural drought monitoring.  相似文献   

19.
China's investments, financial incentives and deductions in terms of ecological conservation are based at the county level. Therefore, the monitoring and assessment of the effects of ecological conservation at the county level is important to provide a scientific basis for the assessment of the ecological and environmental quality at the county scale. This paper quantitatively estimated the dynamics of high-quality ecosystems and vegetation coverage over the past 15 years, and their relationships with the number of ecological conservation programs at the county level were analyzed. Then, the effects of ecological conservation measures on ecological changes at the county level and their regional suitability were assessed and discussed. The results showed that counties with a percentage of high-quality ecosystems greater than 50% were primarily distributed in northeastern China, southern subtropical China and the southeastern Qinghai-Tibet Plateau, and those with a percentage lower than 20% were mostly distributed in northwestern China, the southwestern karst region and the North China Plain. In recent decades, ecological conservation has focused on ecologically fragile regions; more than five ecological conservation programs have been implemented in most counties of the Three River Source Region in Qinghai Province, southeastern Tibet, western Sichuan, the Qilian Mountains, southern Xinjiang and other western regions, while only one or zero have been implemented in the eastern coastal area of China. Over the past 15 years, the proportional area of high-quality ecosystems has increased in approximately 53% of counties. The vegetation coverage of counties in the Loess Plateau, Huang-Huai-Hai Plain, Beijing-Tianjin-Hebei(Jing-Jin-Ji), Sichuan-Guizhou-Chongqing, and Guangdong-Guangxi provincial-level areas has increased significantly. However, it decreased in northern Xinjiang, central Tibet, central and eastern Inner Mongolia, the Yangtze River Delta and other regions. The relationships between the numbers of ecological conservation programs and the indicators of ecosystem restoration response, such as high-quality ecosystem and vegetation coverage, do not show positive correlations. These results suggest that ecological conservation programs should be planned and implemented according to the distribution patterns of high-quality ecosystems and that restoration measures such as afforestation should follow natural principles and regional differentiation under the background of climate change.  相似文献   

20.
由于蔬菜需求量的增加,中国的蔬菜产量不断增加;然而蔬菜地的化学污染会威胁到中国的食品安全。基于蔬菜和粮食作物的播种面积和产量、农业生产投入价格指数、单位面积的农业物质投入、蔬菜和粮食作物生产者价格指数和净利润等数据,本文计算分析了蔬菜地污染造成的中国潜在食品安全风险的变化趋势。研究表明,由于改革开放以来对蔬菜饮食的公共需求的不断增加和蔬菜高的市场价格,蔬菜的播种面积和产量显著增加;然而由于研究时段内蔬菜种植比例的增加,农业物质投入增加所带来的潜在污染风险也在不断增加。通过控制蔬菜地污染,中国的食品安全问题可以得到较大改善。  相似文献   

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