广东省土壤镉含量影响因子解析与评估

影响镉(Cd)含量的因子众多,包括自然影响因子和人为影响因子,而治理Cd污染首先应查明Cd污染来源及其影响因子,这对因地制宜制定Cd污染治理措施及指导相关产业布局具有重要意义.广东省地理状况复杂、经济发达,Cd含量分布区域间差异较大.因此,本文基于Cubist构建土壤Cd含量与相关影响因子关系模型,解析影响广东省土壤Cd含量的主要因子.结果表明:土壤pH值与土壤类型是影响广东省Cd含量最主要的因素,土壤Cd含量与土壤pH值呈正相关关系;赤红壤、砖红壤及紫色土中Cd含量相对较低,潮土、红壤、黄壤、水稻土及石灰土中Cd含量相对较高.Cd含量高值主要出现在第四纪、泥盆纪和石炭纪地质构造运动形成的土壤中.此外,植被指数、土壤粉粒、平均气温、高程、距道路及距河流距离也是影响广东省土壤Cd含量的主要因素.其中,土壤Cd含量与土壤粉粒、高程呈正相关关系,与植被指数、距道路距离、距河流距离呈负相关关系.本文研究结果可为土壤Cd污染治理提供科学的参考依据.     

广东省农村民居地震安全示范工程实施现状分析

结合广东各地农村经济发展状况和民居特点,简要阐述了全省地震安全农居示范工程实施基础,较系统地介绍了当前示范工程实施情况,对存在的不足和工作难点进行了比较深入的分析和科学总结,并提出行之有效的解决方案。     

基于GD_CGE模型的广东省碳排放权交易政策评估

为了评估广东省碳排放权交易制度设计对控制二氧化碳排放及经济发展可能发挥的作用,本文建立GD_CGE模型研究了在碳强度约束目标下碳交易政策的实施效果.首先分析了无减排约束和有减排约束情景下广东宏观经济(GDP)、能源消费总量和碳排放总量的发展趋势;进一步扩展减排约束情景,考察了在全省碳强度减排目标约束下,把电力、水泥、石化、钢铁、造纸、纺织六大部门纳入碳交易体系,并分别按照历史法和潜力法确定行业碳排放约束上限时,实施碳交易政策对宏观经济和能源消费量的影响,模拟了碳市场的交易情况和碳价格.结果表明:在碳强度目标控制下,实施碳交易政策可显著降低部门的减排成本,减小控制碳排放可能对全省GDP的影响,起到了促进广东省低成本节能减排的作用.     

POSTFIRE SUSPENDED SEDIMENT FROM YELLOWSTONE NATIONAL PARK,WYOMING1

ABSTRACT: Wildfires in 1988 burned over 2000 square miles of the greater Yellowstone area in Montana and Wyoming in the largest fires in the history of Yellowstone National Park (YNP). A four-year postfire study to estimate fire-related changes in suspended sediment transport on the Yellowstone River and its principal tributary in YNP, the Lamar River, benefitted from a recently completed three-year prefire baseline study. Both studies took daily depth-integrated samples from April through September. Fire-related changes in suspended sediment were distinguished from natural climatic variations by two methods: comparison of forecast postfire sediment loads estimated with prefire sediment-rating equations to measured postfire loads; and by postfire changes in suspended sediment load expressed per unit volume runoff. Both methods indicated postfire sediment increases that varied according to season. The higher elevation Lamar River basin had little postfire increase in spring snowmelt season sediment but large increases in summer sediment load. The Yellowstone River had postfire increases in sediment load for the spring but did not reflect the large summer increases of its upstream tributary. The reasons for the difference in postfire snowmelt sediment response are unclear but may relate to basin elevation differences, the effects of unburned watersheds, and cooler postfire springs. The few high streamflow snowmelt events in the postfire period mitigated postfire sediment increases.     

HYDROLOGICAL,METEOROLOGICAL, AND AGRICULTURAL RELATIONS IN NORTHERN IRAQ1

ABSTRACT: The northern regions of Iraq, an area comprised of mountains and undulating plains, has for centuries been the main granary for the country. Its agricultural production is largely dependent upon natural rainfall which ranges from about 300 to 1,000 mm/yr. Grain yields can be greatly improved by use of improved varieties and management practices. Equations are developed to show relationships between various hydrologic and meteorologic parameters with yields of wheat and barley. The amount of supplementary water needed to maximize grain yields is also shown.     

WATER CHEMISTRY OF NORTHERN GREAT PLAINS STRIP MINE AND LIVESTOCK WATER IMPOUNDMENTS1

The water from 34 strip mine and 9 livestock water impoundments on the Northern Great Plains was analyzed. In all areas the water was classified as slightly brackish or saline. The dominant ion sequence for the study ponds was Na>Ca>Mg>K and SO₄HCO₃CO₃Cl, which differs from most freshwater by the transposition of Na and SO₄. Even though mean concentrations of total filterable residue were consistently greater in strip mine ponds, statistically significant differences were not found at the p ≤ 0.05 level between strip ponds and livestock ponds. The macronutrients of nitrogen and phosphorus found in the ponds were neither limiting to primary productivity nor excessive for fresh water. Many ponds contain turbid water. Turbidity restricts light penetration and limits photosynthesis besides making the ponds visually unattractive. The source of water for the pond, whether surface runoff or groundwater, seems to have important bearing on turbidity. The most appropriate use of these strip mine ponds is for waterfowl, warm-water fisheries, and other wildlife associated with prairie wetlands. However, even these uses are jeopardized by detrimental concentrations of trace elements in the water (Anderson and Hawkes, 1984).     

Evaluation of a guild approach to habitat assessment for forest-dwelling birds

The applicability of the Habitat Evaluation Procedure (HEP) was assessed for several nongame bird species in the central Adirondack Mountains of New York. Measures for 24 avian species and 33 associated habitat variables were collected during the summers of 1985 and 1986. The accuracy of four published Habitat Suitability Index (HSI) models was examined: pileated and downy woodpeckers, black-capped chickadee, and veery. Chickadee and veery models were judged successful and were then used to predict habitat quality for respective avian foragingguild members. The HSI model/guild approach provided poor predictors of habitat quality for ubiquitous and uncommon species. Information on relative abundance within the geographic region and specific cover types must be included when designing habitat evaluations using the guild approach.     

茂名高岭土矿高岭石的矿物学特征及其涂布性能

茂名高岭土矿的高蛉石,有序度高,晶粒细小(<2微米),沿α、b轴横向连结,无书册状、蠕虫状的大集晶,SiO_2/Al_2O_3值接近高岭石的理论值,Fe_2O_3、TiO_2等杂质含量低于0.5％,并可加工分离,为当前有开发前景的优质涂布原料。     

滇、桂、粤、闽、台灾害链讨论

由于对洪水、台风和巨大风暴潮的长期预测尚有一定困难，因之需要多学科进行综合研究。本文通过对滇、桂、粤、闽、台地区历史上大震后同年或次年发生上述重大气象灾害的事实，讨论了灾害链的预测，同时也讨论了灾害链的形成机制，包括构造活动、北回归线效应以及孟加拉湾大桥活动的双重后果。文中还提出了4条减灾对策。     

广东省近岸海域环境污染现状及防治

介绍广东省近岸海域的污染现状和发展趋势以及近岸海域的污染途径，主要污染物及污染特性，并对近岸海域环境污染原因进行了分析，提出了近岸海域环境污染的防治对策和要进行的具体研究工作。