福建农村生态环境现状与评价指标体系构建

在人口不断增加和经济大规模发展的双重压力下,农村生态环境的形势日益严峻。本文分析了福建农村与农业发展过程中突出的生态环境问题,归结了造成农村生态环境破坏的原因;依据农村生态环境的内涵和特征、农村环境保护理论、农业生态环境保护理论构建了福建农村生态环境指标体系,并利用层次分析法确定了指标权重。该指标体系的建立能够为福建农村生态环境进行定量测度和评价以及为农村生态环境预警系统奠定基础;进一步深刻了解当前福建农村生态环境的现状,为福建农业和农村社会的发展增加深度认识和思考。     

开发区环境管理指标体系研究

开发区环境管理指标体系研究是建立开发区环境管理综合体系的基础性工作,也是考核开发区生态环境建设与管理效果的定量评价工具。本文在探讨环境管理指标体系的确定原则、选择和量化等基础上。提出了一套包括环境保护指标、循环经济指标、绿色管理指标和相关性指标四类指标在内的环境管理综合指标体系。并将该指标体系应用于杭州钱江经济开发区的环境管理实践。结果表明,杭州钱江经济开发区的环境管理完善程度总得分为74．6％,总体上还有待进一步完善,特别是ISO14001管理体系认证和环境质量改善等方面有待进一步加强。     

区域生态安全评价的BP神经网络方法

生态安全评价是建立生态安全预警系统及进行环境管理的基础。为确立有效的区域生态安全评价方法,基于压力－状态－响应概念模型,构建了区域生态安全评价指标体系和评价标准;采用BP神经网络的途径,对安徽省17个地级市的生态安全评价问题进行了研究。结果表明：宣城、池州、黄山为Ⅱ级,亳州、宿州、阜阳、滁州、六安、巢湖、安庆为Ⅲ级,合肥、淮北、蚌埠为IV级,淮南、马鞍山、芜湖、铜陵为Ⅴ级。区域生态安全的BP神经网络评价方法涵义明确,计算过程简单,能区分生态安全的等级,可以应用于具有评价标准的其它生态系统综合评价。     

基于实测光谱分析和MODIS数据鄱阳湖叶绿素a浓度估算

基于遥感的大面积水体监测技术为水环境监测提供了一种有效手段。以鄱阳湖为研究区,以反映水体营养状态的重要指标叶绿素a为研究对象,在测定研究区水体光谱及叶绿素a浓度和收集了相应时间的MODIS数据的基础上,采用浮游藻类指数法（Floating Algae Index,FAI）提取鄱阳湖水体范围,对鄱阳湖水体实测光谱数据进行剔除异常、归一化及光谱微分处理,构建波段差值、比值、归一化差值等光谱指数,利用最小二乘原理迭代分析水体叶绿素光谱响应特征,得出敏感波段范围：673～680 nm与650～665 nm、680～710 nm与650～670 nm、662～671 nm与700～720 nm光谱区间组合。选择最佳通道组合,建立基于MODIS影像的鄱阳湖叶绿素a浓度反演模型,相关系数为067。应用该模型得到2011年秋季鄱阳湖的叶绿素浓度估算值,反演结果显示湖区水体叶绿素浓度总体不高,且在空间分布上湖区水体周边与陆地交界处比湖中心区浓度偏高。分析认为：通过对实测光谱的定量分析,获得对鄱阳湖地区水体叶绿素浓度的光谱特征认识,揭示出其反射光谱的长波漂移现象,为鄱阳湖这一富营养化程度底,且水体分布不均匀区域建立一种叶绿素浓度反演方法,可为该区域长期的水环境管理提供方法借鉴     

Identification of Forest Vegetation Using Vegetation Indices

Abstract

Spectral feature of forest vegetation with remote sensing techniques is the research topic all over the world, because forest plays an important role in human beings' living environment. Research on vegetation classification with vegetation index is still very little recently. This paper proposes a method of identifying forest types based on vegetation indices, because the contrast of absorbing red waveband with reflecting near-infrared waveband strongly for different vegetation types is recognized as the theoretic basis of vegetation analysis with remote sensing. Vegetation index is highly related to leaf area index, absorbed photosynthetically active radiation and vegetation cover. Vegetation index reflects photosynthesis intensity of plants and manifests different forest types. According to reflectance data of forest canopy and soil line equation NIR=1.506R+0.0076 in Jingyuetan, Changchun of China, many vegetation indices are calculated and analyzed. The result shows that the relationships between vegetation indices and forest types are that perpendicular vegetation index (PVI) identifies broadleaf forest and coniferous forest the most easily; the next is transformed soil-adjusted vegetation index (TSVI) and modified soil-adjusted vegetation index (MSVI), but their calculation is complex. Ratio vegetation index (RVI) values of different coniferous forest vary obviously, so RVI can classify conifers. Therefore, the combination of PVI and RVI is evaluated to classify different vegetation types.     

Urbanization in China Based on International Comparison: A Discussion with Two Prevalent Views

Abstract>

Two prevalent views are reviewed on China’s urbanization firstly. Then, this article highlights the characteristics and pattern of urbanization in the world based on the quadrants map, using data of 118 countries or areas. The results indicate that the process of urbanization in the world excluding the data of China has slowed down gradually. A further exploration examines China’s urbanization process and economic development over time, which reveals that both urbanization level and the level of economic development belong to the low-grade coordination pattern. The low level of urbanization is closely connected with the low level of economic development. Actually, China’s urbanization gap appeared during 1985–1995, but it has been eliminating this urbanization gap since 1995 as a result of rapid urbanization growing. The complicated realities revealed in this analysis challenge the existing two prevalent views.     

Developing Mechanism of Rubber-tea-chicken Agro-forestry Model in Tropical Area of China

Abstract

As a typical tropical agro-forestry ecosystem in Wenchang, Hainan Province, China, rational mechanisms of the rubber-tea-chicken eco-agricultural model were studied with the Solow technological level index, stability indicator, harmonizing coefficient, grey correlation coefficient and production dominance. This study focused on rational hierarchical structure, the limiting factors and optimal strategies of the model development based on model structure, resource conditions and external market demands. Results showed that rational mechanism of the rubber-tea-chicken ecosystem model mainly included technological contributions, leverage function of dominance component (livestock husbandry), stability of the model structure and harmony of its components, the model dominant product’s market demand and government’s supporting policies. The contributions of fund, technology, information and talent resources played an important role in improving sustainability and productivity of the agro-forestry model.     

Integrating ecosystem services evaluation and landscape pattern analysis into urban planning based on scenario prediction and regression model

ABSTRACT

Urban planning has become a widely concern for minimizing the negative effects of urban expansion on terrestrial ecosystems. We developed an interdisciplinary modeling framework to evaluate the effectiveness and shortcomings of urban expansion management strategies. A three-step method was applied to Yinchuan Plain in the northwestern of China, including (1) analyzing the relationship between landscape pattern and ecosystem service values through mathematical statistics; (2) predicting landscape pattern and ecosystem services change under different scenarios based on cellular automaton model (SLEUTH-3r model); and (3) designing and validating optimized scenario through integrating historical analysis experiments and future multi-comparison suggestions. Results have suggested that landscape composition and configuration can significantly affect regional ecosystem service values, especially the connectivity and shape of landscape. Compact urban growth policy and medium environment protection policy are the appropriate setting for urban expansion plan. Optimization validation of the combined designed scenario implied the reliability of this method. Our results highlighted the significance of integrating application of landscape pattern analysis, ecosystem service value evaluation, model simulation and multi-scenario prediction in urban planning.     

南水北调丹江口库区土壤中微塑料分布特征及风险评估

为探究丹江口库区土壤中微塑料赋存特征及影响因素,通过对果园、旱地、水田和湿地进行土壤样品采集,利用密度分选、显微镜观察和拉曼光谱仪测定等方法对土壤中微塑料进行鉴定.结果表明,研究区采集的64个样本均有微塑料检出,丰度范围为645~15161 n·kg^-1.空间分布上,库尾高于库中和库首,且表层土壤（0~20 cm）中微塑料的丰度明显低于下层土壤（20~40 cm）.微塑料主要类型为聚丙烯（26.4%）和聚酰胺（20.2%）,粒径主要集中在50~500 μm之间（75%）,常见形状为碎片状（66.2%）.相关性分析显示,土壤微塑料丰度与土地利用、距水面和住宅的距离、人口密度和土壤性状密切相关.从微塑料污染风险来看,72.1%区域微塑料聚合物污染指数处于Ⅲ级和Ⅳ级,丹江口库区存在一定的微塑料污染风险.研究结果可为微塑料风险评估提供支撑.     

基于种群、功能群对比分析洞庭湖浮游植物群落驱动因素及水质评价

浮游植物是水生态系统中最重要的组成部分,因其对水环境变化敏感而常被用于指示水环境状态,但其对环境的响应受分类方法的影响.为了解洞庭湖浮游植物种群(门、属)和功能群(FG)两种分类法对环境的驱动响应特征和适用性,于2019年3～12月分水期对该湖共进行了4次采样,比较分析了浮游植物种群和功能群的分布特征及其与环境因子的响应关系,并对比了TLI指数、 Shannon-Wiener指数、Q指数等评价方法在洞庭湖的适用性.结果表明,洞庭湖共检出浮游植物6门61属,可划分为23个功能群和9个优势功能群,功能群演替趋势为P/MP/D(3月)■月)■月)■(12月).层次分割结果表明,洞庭湖浮游植物的种群分布与变化受环境因子的驱动大于空间驱动;影响浮游植物种群和功能群的主要环境因子为水温(WT)、高锰酸盐指数、溶解氧(DO)、电导率(Cond)、水位(WL)和总磷(TP),环境因子对两者的独立解释性排序相差不大.RDA分析表明,浮游植物功能群对环境因子的响应要优于浮游植物种群.综合对比分析发现,利用Q指数进行水质评价在洞庭湖水体有较好的适用性.