Comprehensive Evaluation of Tobacco Ecological Suitability of Henan Province Based on GIS

The growth of tobacco is sensitive to environment conditions. The tobacco production is strictly restricted by regional cultivated land. Based on the principal of hiberarchy analysis and fuzzy mathematics and the technique of geographic information system （GIS）, the comprehensive evaluation of tobacco ecology suitability were studied according to the actual circumstances of the whole Henan tobacco planting regions, China. The evaluation index system of tobacco ecology suitability of Henan tobacco planting regions was established by choosing 17 evaluation indexes from 3 respects of climate, soil and landform with Delphi method. Furthermore, the membership function was set up according to the effects of each ecology factors on the growth and quality of tobacco suitability. And the analytical hierarchy process （AHP） was used to determine the weight of indexes by using quantitative analysis. Then the tobacco ecology suitability map of Henan tobacco plantation was drawn with GIS software mapGIS. It is found that the most areas of the western and southern parts of Henan Province, China, are the highly suitable regions, accounting for 22.52% of Henan tobacco planting areas. It is because that there are medium air temperature, sunshine and rainfall, medium soil pH value, and high contents of soil organic matter in the regions. Moreover, the topography is hill and massif, and the height above sea level is between 150-800 m there. Some areas of the southern and middle parts of Henan Province are the suitable ones, accounting for 34.99% of Henan tobacco planting areas. It is because that there are enough rainfall, medium air temperature, high contents of available N and available K in the soil in these regions. There are less suitable regions in the northern and eastern parts of the investigated regions because of drought, too high pH value and CI in the soil and irrigation water, accounting for 35.54% of the whole areas. It can be conducted rapidly and correctly by combining AHP and membership function for comprehensive evaluation of tobacco ecological suitability supported by GIS. There are above moderate ecological suitability for most part of tobacco planting fields in Henan Province. The distributions of tobacco ecological suitability calculated are identical with actual tobacco productivity completely.

Research on Methods of Ecological Security Assessment of the Middle and Lower Reaches of Liaohe River Based on GIS

Ecological security assessment and early warning research possess the attributes of spatiality, non-linearity and randomicity, so we must process much spatial information. Spatial analysis and data management are the advantages of GIS, which can define distribution trend and spatial relations of environmental factors, and show ecological security pattern graphically. Spatial differences of ecological security assessment based on GIS are discussed in this paper, of which the middle and lower reaches of the Liaohe River is taken as a study case. First, to work out pressure-state-response (P-S-R) assessment indicators system, and investigate in person and gather information; second, to digitize the watershed; third, to quantize and calculate by the fuzzy method; last, to construct GIS grid database, and expound spatial differences of ecological security by GIS interpolation and assembly analysis.

Ecological Security Evaluation Algorithm for Resource-Exhausted Cities Based on the PSR Model

Today,resource depletion threatens a number of resource-based cities in China.The ecological security problem caused by the long-term exploitation of natural resources is a key issue to be solved in the development of resource-exhausted cities.Using 23 indicators,this study evaluated the ecological security status and development trends of 21 resource-exhausted cities in China from 2011 to 2017.The results showed that from 2011 to 2015,the overall ecological security of this type of city was low,with over 60%of the cities at an unsafe level.However,ecological security improved rapidly after 2016,and by 2017,all of the cities had reached the critical safety level.The top 10 indicators of ecological security included industrial sulfur dioxide emissions,water supply,agricultural fertilizer application,and forest coverage.These 10 indicators’cumulative contribution to ecological security was 48.3%;among them,reducing industrial sulfur dioxide emissions contributed the most at 5.7%.These findings can help governments better understand the ecological security status of resource-exhausted cities,and it can provide a reference for the allocation of funds and other resources to improve the ecological safety of these cities.

Evaluation and scenario simulation for forest ecological security in China

Continuously growing populations and rapid economic development have led to the excessive use of forest resources,and the forest ecosystem is threatened.In response,forest ecological security(FES)has attracted attention.In this study,an integrated dynamic simulation model was constructed using the system dynamic method,and it was used to evaluate the FES in China from 1999 to 2014.A scenario analysis was then used to evaluate the changes in the FES under five forestry policy scenarios for the 2015–2050 period,including the baseline,afforestation policy,harvesting policies,management policy,investment policy,and a policy mix.The results showed that the evaluation values of the FES increased during the period from 1999 to 2002,the period from 2004 to 2010 and the year 2014,and they decreased in 2003 and during the period from 2011 to 2013.During the 2015–2050 simulation period,the FES improved continuously.In particular,China would enter a new stage when the economic systems,social systems and ecosystems were in harmony after 2040.To improve the FES and the current status of the FES,a scenario analysis showed the most suitable scenario to be Scenario 5 from 2015 to 2020 and Scenario 2 from 2021 to 2050.To relieve pressure,the most suitable scenario would be Scenario 5 from 2015 to 2040 and from 2046 to 2050,and the most suitable scenario would be Scenario 4 for 2041–2045.A policy mix(Scenario 5)would be most efficient under current conditions,while the effects of all the benefits of the forestry policies would weaken over the long term.The integrated method can be regarded as a decision support tool to help policy makers understand FES and promulgate a reasonable forestry policy.

Integrated Evaluation of Ecological Security at Different Scales Using Remote Sensing: A Case Study of Zhongxian County, the Three Gorges Area, China

Based on related literature and this research, an ecological security evaluation from the pixel scale to the small watershed or county scale was presented using remote sensing data and related models. With the driver-pressure, state and exposure to pollution-response (DPSER) model as a basis, a conceptual framework of regional ecological evaluation and an index system were established. The extraction and standardization of evaluation indices were carried out with GIS techniques, an information extraction model and a data standardization model. The conversion of regional ecological security results from the pixel scale to a small watershed or county scale was obtained with an evaluation model and a scaling model. Two conceptual scale conversion models of regional ecological security from the pixel scale to the county scale were proposed: 1) scale conversion of ecological security regime results from pixel to small watershed; and 2) scale conversion from pixel to county. These research results could provide useful ideas for regional ecological security evaluation as well as ecological and environmental management.

GIS Based Evaluation System for Ecological Constraints of Dianchi Lake Basin

With the advance of urbanization process and rapid growth of urban population,the construction land scale in Dianchi Lake basin increases at a sharp speed.Due to lack of reasonable scale control and space optimization,many areas have the problem of blind growth in construction land.On the one hand,it results in deterioration of regional ecological environment.On the other,it poses hidden danger for sustainable land use in the basin.Therefore,in order to coordination of regional land use and ecological environment construction,this paper on the basis of the existing various zoning method,the natural ecological conditions and resources environment as the constraint conditions of regional ecological balance,puts forward the Dianchi lake watershed ecological constraint type classification method based on GIS,and discusses the evaluation unit division,index selection and handling technical issues.Through evaluating ecological constraints of Dianchi Lake basin,this study divided Dianchi Lake basin into extremely high,higher,high,medium and low ecological constraint zones.Finally,it came up with guiding and regulating measures for land use of each type of ecological constraint,in the hope of providing scientific basis for optimum allocation of land resources in Dianchi Lake basin.

基于GIS格网模型的广州市土地生态安全格局演化

以公里格网为评价单元,构建基于PSR-NES(压力-状态-响应和经济-环境-社会)模型的土地生态安全测度指标体系,运用突变级数法动态识别2010—2020年广州市土地生态安全格局。结果表明:广州土地生态安全水平空间异质性较为明显,整体呈现“中间低,四周高”的分布格局;2010—2020年,广州市土地生态安全水平先下降后提高,其中,北部生态涵养区土地生态安全水平呈下降趋势,南部生态调节区土地生态安全状况逐渐好转,中部建成区土地生态安全状况不容乐观。未来城镇扩张应尽量避免侵占土地生态安全水平较高的区域,可通过分区治理,科学布局生产、生活、生态空间,优化产业结构,加强生态用地保护力度等措施持续改善土地生态安全状况。

Ecological security evaluation of Africa

Africa,the second largest continent in the world,has achieved remarkable economic and political results through exploration and positive development.Ecological security comprehensively reflects the health and integrity of an ecosystem,and it is broadly defined as the security state of a complex artificial ecosystem composed of natural,economic and social factors.Ecological security determines the potential for sustainable development in Africa,especially with its rapidly developing economies.However,there is a lack of information on the ecological security state of the continent as a whole.In this study,we constructed an evaluation system based on a pressure-state-response model and evaluated the ecological security state of all 54 African countries.The results showed that,at the national level,the ecological security state of the countries in Africa differed,as did their spatial and temporal variations from 1995 to 2016.In general,African countries showed relatively good ecological security.The years 2007 and 2001 were the worst and best years,respectively,in terms of ecological security during the study period.At the regional level,North Africa andWest Africa had the best and worst ecological security,respectively.

基于GIS与层次分析法的嵩县生态环境敏感性评价

以地理信息系统(GIS)为技术支撑,利用层次分析法(AHP),建立生态环境敏感性综合评价体系,对嵩县进行了生态环境敏感性评价。首先,对筛选出的高程、坡度、坡向、水域缓冲区、NDVI、土地利用6个指标进行单因子敏感性评价分析;然后,运用多因子空间加权叠加得到综合评价值变化范围;最后,采取自然间断点法进行生态敏感性分区,构建嵩县综合生态环境敏感性分布图。研究结果表明,嵩县整体生态环境敏感性以中、高为主,极高敏感区、高敏感区、中敏感区、低敏感区、极低敏感区面积占比分别为26.23%、30.05%、18.01%、15.74%、9.97%。极高敏感区和高敏感区主要分布在伏牛山、熊耳山中山区;中敏感区主要分布在海拔较高的山地丘陵区;低敏感区和极低敏感区主要分布人口集中居住区和河谷阶地漫滩。

Evaluation method of the ecological benefits of urban green spaces and application conditions

The importance of ecological benefit analyses about green space systems has been widely discussed on the basis of a perceived bias towards the landscaping effect of green spaces to be built in urban areas as opposed to the perception of comprehensive ecological benefits of designed plant communities. Given the basic principle of ecological benefit analyses and evaluation methods widely applied today, the methodology to calculate ecological benefits and to model the expansion of urban green spaces by CITY- green 5.0 and its conditions for application were explored. We propose that aerial images can be substituted by AutoCAD graphics of a green space containing detailed information of plant dispositions by digitizing the key features during the working process in order to evaluate the ecological benefits quickly and to offer proper guidance to the establishment of small scale green spaces in urban areas. The theoretical foundation, potential application range and prospects for extension of the method are introduced by using the analysis of ecological benefits of the green spaces on the campus of Southwest Forestry College, Kunming, as an example.

Ecological Security Assessment of Red River Basin in Guangxi

[Objective] The study aimed at assessing the ecological security of Red River basin in Guangxi. [Method] Firstly, the ecological security assessment index system of Red River basin was established based on the framework of 'pressure-state-response' model, and index information of ecological security assessment was extracted by using RS and GIS technology; afterwards, the ecological security of Red River basin was divided into five grades according to ecological security index, and the distribution and characteristics of ecological security at various levels were analyzed; finally, the measures to maintain the ecological security of Red River basin were put forward on the basis of problems in ecological security. [Result] Most areas of Red River basin in Guangxi were in generally safe state, especially Lingyun County, Fengshan County, Du'an County, Dahua County, Shanglin County, Binyang County, Guiping City, etc., and the area accounted for 74.25% of total area; next came safer state (12.74%), the regions in the two states above were the most important environmental areas of Red River basin. The ecological security problems of Red River basin were mainly related to fragile ecological environment, lagging economic development, rapid population growth, excessive development and utilization of natural resources and so forth. [Conclusion] The research could provide scientific references for the rational development and utilization of land resources, protection and construction of ecological environment in Red River basin.

基于GIS的怒江州建设用地生态适宜性评价

综合自然环境、社会经济等因素对建设用地生态适宜性进行定量分析评价可有效解决城市扩张与土地资源有限的矛盾。以云南省怒江州为研究区,根据区内地质环境特征,选取高程、坡度、河流、湖库、归一化植被指数、与建成区距离、与交通距离、人口密度和生产总值9个指标因子,利用层次分析法(AHP)和GIS的空间分析对怒江州建设用地生态适宜性进行了评价。结果表明,最适宜和适宜区占总面积的21.085%,其中兰坪和泸水区域地质环境最优越,建议怒江州向南发展,同时做好生态环境保护工作。

Geographical Information System-Based Assessment of Ecological Security in Changbai Mountain Region

Ecological security defined as the creation of a condition where the physical surroundings of a community provide for the needs of its inhabitants without diminishing its natural stock,which is important for regional security and social stability.In recent years,land use patterns in the Changbai Mountain region have changed significantly with intensive human activities,and consequently led to increasing problems in regional ecological security.Based on the Pressure-State-Impact-Response(PSIR) model and the mathematical method of catastrophe progression supported by geographical information system(GIS),the ecological security situation of the study area under land use and cover change(LUCC) was evaluated.The results indicated that the ecological security in Changbai Mountain region varied nonlinearly,which got better from 1990 to 2000 but became worse from 2000 to 2007,the ecological security levels in Changbai Mountain region were mainly medium and medium to low during the past 17 years,with higher values of Ecological Security Index(ESI) in the central region and lower values in the east and west,the ecological security situation was more serious in the settlements and river valleys,where the LUCC was most remarkable.

Study on New Urbanization and Urban Ecological Security Assessment

Taking the relationship between new urbanization and urban ecological security protection as research object, based on pressure -status - response model, taking Gaochun （Gucheng Lake basin） and Zhangjiakou （Guanting Reservoir basin） as the examples, basin ecological security in its new urbanization process was evaluated. Based on the principle of comprehensiveness, representativeness and data availability, evaluation indexes were selected, and index system was established. Mathematical function of evaluation indexes was established, and security index of each evaluation indicator in index layer was determined. Using weighted average method, ecological security indexes in the two areas were obtained. On the basis of comparison and analysis, it is proposed that we must deal with urban ecological security problem in new urbanization process, thereby truly achieving ultimate value orientation of new urbanization construction oriented by people.

Ecological suitability evaluation for urban growth boundary in red soil hilly areas based on fuzzy theory

The fuzziness exists in spatial distribution of geographic data of land suitability evaluation processes,which makes it difficult to quantify land boundaries by using traditional binary logic-based overlay model.Aiming at this limitation,an ecological suitability evaluation analysis model was presented based on fuzzy theory and a research on urban growth boundary(UGB) of the Great-Hexi Leading District(GHLD) of Changsha was conducted.With the support of GIS,RS and MATLAB,slope,elevation,vegetation,soil productivity,soil permeability,water body and land use are selected as the input of model according to the characteristic properties of soil and terrain in red soil hilly areas.The running result of this model indicates that the ratios of highly suitable land,suitable land,moderately suitable land and unsuitable land in GHLD are 18.75%,10.31%,64.16%,6.78%,respectively.This result accords with spatial structure worked out by Space Development Strategy Planning of GHLD,Based on this result,several suggestions are made to guide UGB developments in future.

基于GIS的青藏高原生态服务功能定量评价

生态系统服务是保障人类生存发展的重要支柱和实现区域可持续发展的重要保障。基于植被净初级生产力(NPP)定量指标评估法、GIS空间分析法、生态服务功能综合评价法与一元线性回归趋势线法,对2000—2015年青藏高原水源涵养、水土保持、防风固沙和生物多样性维护功能的空间分布特征及重要性进行评价。结果表明:(1)水源涵养、水土保持、防风固沙、生物多样性维护功能指数东南高、西北低,呈现出由东南向西北递减的变化趋势;(2)从上述生态服务功能重要性分级特征来看,4类生态系统服务功能一般区面积最大,分别占高原总面积的27.06%、19.73%、61.44%、41.7%;生态服务功能较弱的区域面积最小,分别占高原总面积的16.47%、16.96%、0.97%、4.06%;(3)从综合重要性分级特征看,生态系统服务功能一般区面积最大,占高原总面积20.72%,生态系统服务功能较弱区面积最小,占高原总面积的16.73%,总体上综合评价结果优于单一生态功能评价;(4)2000—2015年来青藏高原生态功能总体上呈现两大明显特征,即高原南部、三江源区域、青海湖南端及祁连山地区综合生态服务功能呈下降趋势,藏北高原、藏南谷地、横断山区综合生态服务功能呈增加趋势,其他地区基本保持不变。研究成果可为青藏高原重点生态功能区与生态红线的划定,加强生态环境分区管理及建立健全生态屏障提供参考,为区域生态系统综合评价提供借鉴。

基于RS和GIS的朝阳县矿区生态环境评价

利用Landsat 8 OLI遥感影像、ASTER卫星DEM数据,提取了朝阳县地形坡度、植被覆盖度信息,运用层次分析法确定了地质安全隐患、区域重要程度、土地损毁程度等12个评价指标权重,根据相关规范确定评价指标等级,建立矿区生态环境评价模型。运用网格法将研究区分为若干个评价单元,将评价指标进行赋值、叠加,确定各个矿区评价分值,依据评分将研究区分为影响严重区、较重区、较轻区与无影响区4个区域。研究表明:1)矿区生态环境影响严重区主要分布在朝阳县北部铁矿区和西南部锰矿区,该区域地质灾害隐患较严重,矿区地质环境复杂,开采破坏程度严重,生态环境影响严重。2)朝阳县生态环境影响最为集中区域为朝阳县北部矿区,该区域为群采区,开发强度高,开采时间长,形成严重的生态环境问题。3)矿山开采导致的土地损毁问题较为突出,不同土地类型的损毁面积占全县采矿用地面积的41.6%,矿区生态修复潜力较大。识别与分析朝阳县矿区生态环境问题,为朝阳县生态修复规划提供理论支撑,对后续矿山生态修复措施研究,绿色矿山建设工作的开展有着重要的意义。

Study on Low Hilly Cities Land Suitability Evaluation Method Based on Ecological Considerations—A Case Study of Longfeng New Town in Sichuan

Attention to the development of low hilly cities increases, in order to guide their development towards efficient and ecological land use. This paper takes eco-safety into consideration in the future layout of land for construction, and incorporates ecological security factors into traditional methods of land suitability evaluation based on topographic conditions. Taking the Longfeng New Town in Suining City as an example, the GIS platform is used to superimpose various evaluation factors. The evaluation index system is determined using the combination of the Delphi Technique and AHP. The result of correcting traditional land suitability evaluation is obtained, which provides decision support for improving the scientificity of land use planning and layout.

GIS支持下生态敏感性评价--以济南市长清区为例

为深入研究长清区生态系统对区域内部环境对于人类活动干扰的敏感程度,选定2020年长清区Landsat-8遥感影像和30 m分辨率的数字高程模型为基础数据,并对其进行前期准备,得到以高程、坡度、坡向、水系和归一化植被指数(NDVI)作为评价指标的济南长清生态敏感性评价体系。首先进行单因子评价,并将研究区分为基于该因子评价下的高敏感区、中敏感区、低敏感区以及非敏感区,利用层次分析法确定各敏感因子的权重,包括高程、坡向、坡度、水系、NDVI,而后经过加权叠加获得所需的济南市长清区生态敏感性综合评价图。