广州东进扩张下的萝岗区土地利用与景观动态分析

以研究区1979年MSS1、990年LandsatTM、2000年LandsatETM以及2006年Aster 4个时段的卫星遥感影像为基础数据,运用RS与GIS技术手段,结合FRAGSTATS景观格局分析软件,对萝岗区近30年来的土地利用与景观格局变化进行了定量分析。研究表明：研究区未利用土地、园地及耕地面积大幅减少,林地与城镇用地面积显著增加。1979—2006年期间,2000年是一个分水岭,2000年前景观的连接度下降,破碎程度增加,景观斑块的形状趋于复杂化,景观结构组成的复杂性也趋于增加。2000年后各指数呈现了逆转的趋势,表明萝岗区为建设成为国际化生态型新城区,在后期的城市化进程中特别重视了生态环境的保护及建设。     

WATER RESOURCES DEVELOPMENT IN THE MULLICA RIVER BASIN1

ABSTRACT: The potential withdrawal of water from the Mullica River-Great Bay Estuary is southern New Jersey prompted a joint study by biologists and engineers to determine the maximum supply of water that could be diverted from the basin without causing undue environmental impacts. The effect of removal of water from the basin over long periods of time was simulated by review of records of a severe drought. Based on analysis of streamflows and salinities during these drought conditions, minimum mean monthly streamflows were determined corresponding to the maximum salinities tolerable by the fish and shellfish communities, important sources of revenue and recreation in the region. A physically optimized, chance constrained linear programming model was developed for the conjunctive use of ground and surface waters. Adjusting water withdrawal from streamflow and groundwater sources according to physical and seasonal criteria would permit maximum use of the basin's resources, with no additional burden on the ecology of the estuary.     

免拆模板复合剪力墙粘结性能试验研究

免拆模板复合剪力墙体系是适应当前新型建筑体系需求而发展起来的新型节能结构体系。它具有节约能源、增大使用面积、优良的抗震性能及工厂化的施工工艺等优点。笔者专门对免拆模板复合剪力墙体系进行了研究 ,针对 3种不同聚苯板截面和 4种不同免拆模板截面进行粘结性能试验 ,通过试验总结出影响免拆模板与现浇混凝土之间粘结性能的因素 ,并对其作用机理进行分析 ,以期对新型建筑节能体系的发展有所贡献。     

AQUATIC ORGANISMS AND HEAVY METALS IN MISSOURI'S NEW LEAD BELT1

The New Lead. Belt of southeastern Missouri has recently become the largest lead producing region of the world. The impact of this rapid development on the previously rural and undeveloped region of the Missouri Ozarks is the subject of a continuing interdisciplinary study. Since the industrial development began, there have been a number of nuisance biological blooms in several of the small streams receiving effluent from the mines and mills. The major constituents of the problem algal growths were identified and found to include: Cladophora, Oscillatoria, Mougeotia, Zygnema, Spirogyra, Cymbella, and a variety of other stalked and non-stalked diatoms. Secondary blooms of Sphaerotilus were observed to reach problem proportions in some streams, particularly in the autumn. Finely ground rock flour and mineral particles escaping from tailings dams were found to be trapped by the stream vegetation. Concentrations of lead, zinc, copper, and manganese in the algal and bacterial mats were found to be inversely related to distance downstream from the tailings dams. Consumer organisms, including crayfish, snails, aquatic insects, tadpoles, minnows and larger sunfish were analyzed to determine the extent of dissemination and concentration of the heavy metals through food chains. Preliminary results indicated insignificant concentrations of heavy metals in those consumer organisms studied, though in at least one problem stream the normal consumer organisms mentioned were markedly reduced in numbers.     

长江三峡库区猕猴桃资源特点及其发展策略

猕猴桃是我国特有的珍贵果树资源，长江三峡库区是猕猴桃的原产中心地带，物种资源丰富，生态条件优越，发展潜力较大。本文分析了三峡库区猕猴桃的资源特点，阐述了开发利用猴桃桃资源的必要性和优越性，以及有利条件，提出了发展猕猴桃生产的若干策略。     

Relationship of Land‐Use/Land‐Cover Patterns and Surface‐Water Quality in The Mullica River Basin1

Abstract: We describe relationships between pH, specific conductance, calcium, magnesium, chloride, sulfate, nitrogen, and phosphorus and land‐use patterns in the Mullica River basin, a major New Jersey Pinelands watershed, and determine the thresholds at which significant changes in water quality occur. Nonpoint sources are the main contributors of pollutants to surface waters in the basin. Using multiple regression and water‐quality data for 25 stream sites, we determine the percentage of variation in the water‐quality data explained by urban land and upland agriculture and evaluate whether the proximity of these land uses influences water‐quality/land‐use relationships. We use a second, independently collected water‐quality dataset to validate the statistical models. The multiple‐regression results indicate that water‐quality degradation in the study area is associated with basin‐wide upland land uses, which are generally good predictors of water‐quality conditions, and that both urban land and upland agriculture must be included in models to more fully describe the relationship between watershed disturbance and water quality. Including the proximity of land uses did not improve the relationship between land use and water quality. Ten‐percent altered‐land cover in a basin represents the threshold at which a significant deviation from reference‐site water‐quality conditions occurs in the Mullica River basin.     

新时期环境监测工作的几点思考

新时期环境监测面临的任务复杂而艰巨,如何才能从容应对各种突发事件,如何才能更好的为环境管理服务,如何才能进一步提高监测分析水平,构建先进的预警体系,是不断拓展环境监测领域,加快信息化建设步伐的必由之路。     

几种粪大肠菌群检测方法的比较

粪大肠菌群作为水体粪便污染的指示菌,其在地表水水质监测评价中具有重要作用。采取精确、快速的粪大肠菌群检测方法,对控制流行疾病的发生和传播有重要的科学意义。为此对应用多管发酵法、滤膜法、快速检测法(纸片法)、酶底物法检测粪大肠菌群的优缺点作了对比研究。得出了快速检测法(纸片法)、酶底物法有较准确、快速等方法特性,有较好的实用价值。     

化工区土壤中多环芳烃的污染特征及其来源分析

系统采集了天津滨海新区3个化工区28个表层土壤样品,利用GC/MS分析了16种US EPA优控多环芳烃(PAHs)的含量和组分特征,运用环数比值法和主成分因子载荷法揭示了其污染来源.结果表明,化工区土壤中PAHs最高含量达5 991.7　ng·g^-1(塘沽化工区),平均含量1 18５.０　ng·g^-1,与国内外相关研究比较,处于中高等污染水平,工业污染排放已明显影响到周边环境中PAHs的残留,且塘沽化工区＞汉沽化工区＞大港采油区;塘沽和汉沽2个化工区土壤中毒性较高的4环和5环PAHs均高于其他环数PAHs,大港采油区3环所占比例明显占主导;土壤有机碳(TOC)和PAHs之间存在显著相关关系(n=28,R²=0.847,p＜0.01),TOC是影响研究区域PAHs在土壤中分配的一个重要因素;煤燃烧的排放是化工区土壤中PAHs污染的主要来源,石油类挥发或泄漏对大港采油区影响显著.     

云南省保山市隆阳区地质灾害空间分布规律及易发性分区与评价

保山市隆阳区地处云南省西部,境内有高黎贡山、怒江、澜沧江等大型山脉和河流,地形起伏大,地层出露比较齐全,地质构造复杂,气候条件多样,人类工程活动影响强烈,这些都为地质灾害提供了很好的成灾条件。通过野外实地排查与核实发现,保山市隆阳区现状地质灾害发育,并且类型齐全。利用GIS与GPS技术将调查结果数字化到1∶10万地形、地质图上,可以看出保山市隆阳区地质灾害空间分布规律总体上呈现出北部、东南部分布较多,中部、西部分布较少的特点。在现状地质灾害调查、研究的基础上,采用"地质灾害综合危险性指数法"对保山市隆阳区进行地质灾害易发性分区,将整个保山市隆阳区划分为4个大区共11个亚区,结合成灾地质规律,对各个分区进行了详细评价,分析地质灾害形成的主要原因和诱发主导因素,并提出了相应的防治对策。