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Eco-environmental vulnerability assessment is crucial for environmental and resource management. However, evaluation of eco-environmental vulnerability over large areas is a difficult and complex process because it is affected by many variables including hydro-meteorology, topography, land resources, and human activities. The Thua Thien – Hue Province and its largest river system, the Perfume River, are vital to the social-economic development of the north central coastal region of Vietnam, but there is no zoning system for environmental protection in this region. An assessment framework is proposed to evaluate the vulnerable eco-environment in association with 16 variables with 6 of them constructed from Landsat 8 satellite image products. The remaining variables were extracted from digital maps. Each variable was evaluated and spatially mapped with the aid of an analytical hierarchy process (AHP) and geographical information system (GIS). An eco-environmental vulnerability map is assorted into six vulnerability levels consisting of potential, slight, light, medium, heavy, and very heavy vulnerabilities, representing 14%, 27%, 17%, 26%, 13%, 3% of the study area, respectively. It is found that heavy and very heavy vulnerable areas appear mainly in the low and medium lands where social-economic activities have been developing rapidly. Tiny percentages of medium and heavy vulnerable levels occur in high land areas probably caused by agricultural practices in highlands, slash and burn cultivation and removal of natural forests with new plantation forests. Based on our results, three ecological zones requiring different development and protection solutions are proposed to restore local eco-environment toward sustainable development. The proposed integrated method of remote sensing (RS), GIS, and AHP to evaluate the eco-environmental vulnerability is useful for environmental protection and proper planning for land use and construction in the future.  相似文献   
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As a key issue in China’s urban development, urbanization creates increasing pressure on the environment. Thus, a better understanding of the relationship between urbanization and the eco-environment is necessary for Chinese policy makers to realize sustainable urbanization development. Making reference to physical coupling models, we developed a coupling coordination degree model in order to examine the relationship between urbanization and the eco-environment in Shanghai, using data from 1980 to 2013. The comprehensive level of Shanghai’s urbanization process during the study period was estimated using an index composed of four primary indicators, namely: demographic urbanization, spatial urbanization, social urbanization, and economic urbanization. We also developed an index system for the eco-environment, which was based on four primary indicators: the environmental level, eco-environmental endowment, eco-environmental pressure and eco-environment response. The entropy method was subsequently employed in order to identify the contribution made by each indicator to the compound system during the study period. The results show that: (1) economic urbanization and eco-environmental response made the greatest contributions to the urbanization subsystem and the eco-environmental subsystem, respectively—these are thus the key factors to consider in policy decisions aiming to adjust the coupling coordination degree between the two subsystems; (2) the two parameters α-urbanization and β-eco-environment were found to have minimal effect on the coupling coordination system; (3) the coupling coordination between urbanization and the eco-environment produced an S-shaped curve, and both subsystems were found to have evolved from seriously unbalanced development at the start of the study period into superiorly balanced development at the close of the study period. The results of this study hold important implications for efforts to achieve the coordinated development of both urbanization and the eco-environment.  相似文献   
3.
黄山市土地利用变化的生态效应研究   总被引:4,自引:0,他引:4  
崔淑卿  赵来  吕成文 《生态科学》2006,25(4):350-353
利用黄山市1987年、1995年、2000年三期TM遥感影像数据,对研究区内近十年来土地利用变化及其对生态环境的影响进行了深入分析.研究表明:近10年来黄山市生态环境有退化的趋势,其间1987~1995年退化相对较严重.同时,在不同区域间存在分异,祁门县的生态环境质量最好,屯溪区的生态环境质量最差.在研究时段内,除休宁县的生态环境有所改善,其他地区都存在不同程度的退化,其中黄山区的生态环境退化相对最为严重.生态环境质量和土地利用类型之间,存在很大的相关性,尤其是土地利用类型中的林地面积和生态环境质量息息相关:森林覆盖率高,生态环境好;而森林覆盖率下降,生态环境质量也相应下降.  相似文献   
4.
An indicator of quantifying eco-environmental vulnerability was established by synthesizing 12 variables, mainly retrieved from satellite data with incorporation of analytical hierarchy process (AHP). Six vulnerability levels of potential, slight, light, medium, heavy, and very heavy were graded to depict changes of vulnerability over temporal and spatial scales. The proposed approach was employed to study spatiotemporal eco-environmental vulnerability with Landsat data acquired in 1989, 2003, and 2014 for the Thua Thien – Hue Province, Vietnam. Over the time periods of 1989–2003 and 2003–2014, both heavy and very heavy vulnerability levels exhibit an increasing trend in both magnitude and spatial size: The former raised from 5.9% in 1989, to 7.9% in 2003, and 15% in 2014; and the later increased from 1.2% in 1989, to 3.2% in 2003, and 7.3% in 2014. Both levels mainly appeared on urbanized area, bare land, semi-bare land, agricultural land, and sparse forests. In contrast, there was a significant decline in potential vulnerability level with 36.4% in 1989, 30.9% in 2003, and 19.2% in 2014, while the remaining vulnerability levels slight, light, and medium fluctuated slightly, increased in 2003 and decreased in 2014. Supporting reasons for such changes include: (1) deforestation, agriculture intensification, construction of three hydro-electric projects during the period 2003–2014; and (2) significant expansion of urbanized area leading to differences in thermal signatures in urban areas as compared with rural areas. The findings demonstrate that eco-environmental vulnerability is primarily exaggerated by anthropogenic activities through land use/land cover (LULC) changes and further enhanced by natural processes including disasters in the Thua Thien – Hue Province of Vietnam. The correlation between land surface temperature (LST) and Normalized Difference Built-up Index (NDBI) is found to be positively correlated with 0.87, 0.89, and 0.84 for 1989, 2003, and 2014, respectively. In contrast, LST-Normalized Difference Vegetation Index (NDVI) is found negatively correlated with respect to the spatiotemporal trend of environmental vulnerability with −0.81, −0.81, and −0.76 in 1989, 2003, and 2014, respectively. In addition, areas having potential, slight, and medium thermal environmental levels are decreased from 1989 to 2003 to 2003–2014. At the regional scale, increased anthropogenic activities through land’s modification have intensified the eco-environmental vulnerability in the study area. The currently proposed methodology is feasible for evaluating long-term eco-environmental changes processes by using remote sensing data, and valid for the other regions.  相似文献   
5.
区域土地整理生态环境评价及其时空配置   总被引:2,自引:0,他引:2  
土地整理生态环境评价及其时空配置是进行区域土地整理的科学基础.文中以山东省青州市为例,在深入分析土地整理特点和青州市自然社会条件的基础上,构建了土地整理生态环境评价指标体系和评价模型;运用综合指数法和GIS技术取得各评价单元综合得分,在此基础上进行了区域土地整理时空配置.结果表明,青州市耕地和未利用地共1 446 km2,近期土地生态环境整理区主要分布于平原区的西北部,占耕地和未利用地总面积的15.35%,中期整理区分布于平原区的西北部和中部,占13.58%,远期整理区分布在平原区的北部,40.71%,不整理区分布于丘陵区,占30.36%.研究结果可为青州土地整理规划和实施提供科学依据.  相似文献   
6.
沙冬青根瘤菌的抗逆性   总被引:14,自引:0,他引:14       下载免费PDF全文
沙冬青(Ammopiptanthus mongolicus)是西北荒漠地区珍稀常绿阔叶灌木,综合沙冬青分布区内气候、土壤和水分等因子,选取宁夏中卫县沙坡头、内蒙古磴口县、内蒙古阿拉善左旗、内蒙古乌拉特后旗作为样区,于2004年4月中下旬沙冬青的花期调查和收集根瘤,并结合地理环境对分离得到的根瘤菌进行抗逆性初步分析。调查发现根瘤的生成及其在宿主植物上的着生部位、大小、形状、颜色等因生境条件的不同而有所差异,水分是其主要的影响因子;分离得到根瘤菌17株,对其耐盐性、耐酸碱性、生长温度范围和抗生素抗性进行了研究。结果表明,64.7%的菌株可以在含3%NaCl的YMA培养基上生长;94.1%的菌株可以在pH 5~11的范围内生长;全部菌株在60 ℃处理10 min后仍能生长;不同菌株对不同抗生素表现出不同的抗性,ZW4和WH41对各抗生素表现出较强的抗性。分离自磴口县的根瘤菌普遍表现出较强的抗酸碱和抗高温的能力,这是对其环境的适应。本研究证明沙冬青根瘤菌具有较强的抗逆性,但菌株间存在差异,这可能是对沙冬青分布区多种景观生态类型的适应。同时测定了几种伴生植物中间锦鸡儿(Caragana intermedia)、猫头刺(Oxytropis aciphylla)和柠条(Caragana corshinskii)根瘤菌的抗逆性,与沙冬青根瘤菌表现出一定的相似性,具较强的抗逆性,说明生态环境对豆科植物-根瘤菌共生体有重要的影响。沙冬青的高抗性可能与沙冬青根瘤菌的高抗性有关。沙冬青与其根瘤菌的共生关系有利于其植物群落的发育和多样性的维系。  相似文献   
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选用 6个不同品质类型小麦品种在 4个生态点进行分期播种试验, 系统分析了不同生态环境下小麦籽粒产量与品质的变异特征及其与主要气候生态因子间的关系。结果表明 :生态点、品种以及地点×品种互作对籽粒产量、千粒重、蛋白质、湿面筋和淀粉含量、沉降值与降落值的影响均达到显著水平 ;不同播种期处理对产量与淀粉含量的影响达到极显著水平, 而播种期×品种互作对千粒重、降落值、淀粉含量及沉降值的效应达到显著水平 ;地点×播种期×品种互作仅对产量、湿面筋、淀粉含量与沉降值有显著的影响。在 4个不同生态点中, 南京点的籽粒蛋白质与湿面筋含量最低, 但淀粉含量最高 ;徐州点的产量和千粒重最大 ;泰安点的蛋白质含量与湿面筋含量最高, 沉降值最小 ;保定点的产量、千粒重最小, 但沉降值最大。不同播种期处理下, 适播与晚播的籽粒蛋白质含量、湿面筋含量、淀粉含量、沉降值与降落值都显著高于早播, 而早播期的产量和千粒重最大。各小麦品种在不同地点与播种期下产量与品质性状的变异中以降落值的变异系数为最大, 淀粉的变异为最小。开花至成熟期的日均温与淀粉含量呈线性负相关, 与产量、蛋白质和湿面筋含量及降落值呈二次曲线相关关系 ;日温差与产量和千粒重呈二次曲线相关关系, 籽粒蛋白质和湿面筋含量、沉降值及降落值则随昼温差的增加线性递增 ;开花至成熟期降雨量与产量、千粒重都呈现先升后降的二次曲线相关关系, 而与籽粒蛋白质含量和降落值呈现线性负相关关系 ;籽粒蛋白质和湿面筋含量与降落值随开花至成熟期的累计日照时数呈现线性正相关关系。  相似文献   
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全球四大湾区生态环境综合评价研究   总被引:5,自引:1,他引:4  
全球四大湾区既是经济发达区,也是生态环境脆弱区,对全球可持续发展至关重要。粤港澳大湾区的生态环境问题正在限制其可持续发展,有碍于全面建成国际一流湾区目标的实现。然而,过去的研究对生态环境方面关注较少,缺少湾区生态环境综合评价体系的构建。通过综合国内外统计和遥感多源数据,建立四大湾区生态环境评价数据库;围绕生态质量,环境质量和资源利用效率建立指标体系,构建湾区生态环境综合评价指数。结果表明:2015年,生态环境综合评价,东京湾区 > 旧金山湾区 > 纽约湾区 > 粤港澳大湾区;生态质量,纽约湾区 > 旧金山湾区 > 粤港澳大湾区 > 东京湾区;环境质量,旧金山湾区 > 东京湾区 > 纽约湾区 > 粤港澳大湾区;资源利用效率,东京湾区 > 旧金山湾区 > 纽约湾区 > 粤港澳大湾区。2005-2015年,粤港澳大湾区环境质量增速缓慢,在生态质量和资源利用效率增幅排名首位。旧金山湾区和纽约湾区优势在生态和环境质量,短板在资源利用效率;东京湾区在资源利用效率方面优势明显,短板在生态质量;综合来看,粤港澳大湾区与其他湾区都存在差距。研究建议粤港澳大湾区从生态空间、生态环境治理和资源利用方面,吸取发达国家湾区的经验。  相似文献   
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