2005—2010年湖南锡矿山矿区生态系统空间格局变化分析

利用地理信息系统与遥感技术,对2005—2010年湖南省永州市锡矿山矿区生态系统空间格局变化特征进行了定量分析。结果表明,矿区植被面积逐渐减小,而矿山设施、矿山地质灾害、矿区敏感物和采矿场的面积则有所增加;矿区各类型的生态系统之间存在着相互转换的现象,但相互转换的面积并不大;基于景观指数方法的分析发现矿区生态系统的斑块数、各类别的边界密度、生态系统斑块密度均呈现增大趋势,而矿区聚集度指数整体呈现缓慢下降的趋势。     

The net primary productivity of Mid-Jurassic peatland and its control factors: Evidenced by the Ordos Basin

Using the large-scale thick 4# coal seam from the Mid-Jurassic in the southern Ordos Basin as an example, this paper studied the net primary productivity(NPP) level of the Mid-Jurassic peatland, and discussed its control factors. Geophysical logging signals were used for a spectrum analysis to obtain the Milankovitch cycle parameters in coal seam. These were then used to calculate the accumulation rate of the residual carbon in 4# coal seam. The carbon loss can be calculated according to the density and residual carbon content of 4# coal seam. Then, the total carbon accumulation rate of the peatland was further derived, and the NPP of peatland was determined. The results show that the NPP of MidJurassic peatland is higher than that of Holocene at the same latitude. Comprehensive analysis indicates that the temperature, carbon dioxide and oxygen levels in atmosphere are the main control factors of the NPP of Mid-Jurassic peatland.     

DEA方法在选矿厂生产力利用率分析中的应用

在简要分析国内外生产力利用率分析理论方法的基础上，应用DEA方法，把输入变量划分为“受限制”和“不受限制”两部分，并以某选矿厂为例，对其生产力利用率状况进行了全面定量分析，找出了非有效决策单元今后改进的方向，研究结果与企业的实际情况和定性分析相吻合，证明了本方法的有效性。     

鱼骨型水平井产能计算公式推导

根据等值渗流阻力方法和水平井产能计算公式推导了鱼骨型水平井产能计算公式.利用所推导的公式对实际油井产能进行了计算,并与实际生产数据进行了对比.结果表明,计算精度能够满足工程计算的需要.     

Assessment on soil fertility of Dongting Lake wetland area （China） based on GIS and fuzzy evaluation

Using soil data of the Second National Field Survey, the soil fertility of wetland ecosystem of Dongting Lake was evaluated by using the technology of GIS and method of fuzzy evaluation. Integrated with the wetland actuality of Dongting Lake and particularity of paddy, seven factors (including soil organic matter, total nitrogen, total phosphorus, total potassium, available phosphorus, available potassium, and pH value), closely related with soil fertility, were chosen to establish the index system of synthetical evaluation. Based on the effect degree of each selected index on soil fertility, a judgment matrix was built, and the weight coefficient was determined by the method of correlation coefficient. Finally, under the support of the spatial analysis module of GIS (Geographic Information System), the spatial distribution properties of soil fertility in wetland ecosystem of Dongting Lake were studied. The results show that the soil fertility of Dongting Lake wetland ecosystem is not very good, and the area of type III and type IV achieves 69.8%. As a result, many countermeasures should be taken to improve the soil fertility. As for the spatial properties, the soil fertility level of central and west Dongting Lake is much higher than that of north and south part. The soil fertility of paddy field surpasses that of red soil, and the contents of soil organic matter and total nitrogen in paddy field are large.     

低渗油藏采收率确定新方法

通过对油藏相渗曲线的归一化处理,利用达西定律理论,建立采油指数与含水率的关系;再通过油藏确定的单井经济极限采油量和油藏极限生产压差求出极限采油指数,从而得到极限含水率;最后以最终水驱体积波及系数与储层退汞效率计算出采收率。并以低渗透油藏为实例验证了该方法的正确与适用性,说明该方法对油田开发中确定低渗油藏采收率具有科学的指导意义。     

API gravities,vanadium, nickel,sulfur, and their relation to gross composition: Implications for the origin and maturation of crude oils in Western Desert,Egypt

In the present study, the geochemical analyses of API gravities, vanadium, nickel, sulfur, and bulk composition were performed on eight samples from productive wells in Gindi, South Deep Abu-gharadig, Abu-gharadig, Dahab-Merier, and Faghure basins locates in the North Western Desert. The results were used to describe the source organic matter input, depositional environment, assess the degree of thermal maturity, and to correlate between crude oils to determine the genetic relationship between hydrocarbon generation and their source rock for the studied oil samples. The results showed that a wide range of crude oil parameters exists in this data, indicating that a variety of oil types is represented. Crude oils range from unaltered to altered by vanadium, nickel, and sulfur concentrations, V/Ni and saturate fraction were used to classify the oils. Oils are classified into two groups. Group I contains oil samples from Gindi, South deep Abu-gharadig and Abu-gharadig, and Dahab-Merier that are generated from organic matter input deposited in marine environment under anoxic to suboxic conditions. Group II from Faghur basin possess high Pr/Ph ratios suggesting high contribution of terreginous organic matter deposited under relatively oxic conditions.     

The application of ecological indicators to assess the ecological condition of a lake

Application of ecological indicators to assess what is called ecosystem health and ecosystem integrity has gained an increasing interest. The idea is in short to find an index which will account for the most crucial properties of ecosystems. Exergy, the amount of potential work that the system possesses, structural exergy (exergy/biomass) and buffer capacities have, in this paper, been proposed as measures of ecosystem health. The applicability of using these three concepts in practical lake management was investigated in 15 case studies.     

地下水灌溉服务市场对农业用水生产率的影响

基于2001年和2004年在河北省和河南省的实地调查,定量分析地下水灌溉服务市场对农业用水生产率的影响。研究结果表明,地下水灌溉服务市场有利于提高作物单位用水的生产率(产出能力和经济价值)。因而,有效地促进地下水灌溉服务市场可以在一定程度上提高水资源的管理水平,缓解水资源短缺的矛盾。     

陆地生态系统模型及其与流域水文模型耦合的研究进展

陆地生态系统与流域水文循环通过复杂的生理学过程和水文学过程相互影响、相互作用,本文对陆地生态系统模型及其与流域水文模型的耦合研究进行了综述和讨论。将陆地生态系统模型分为基于静态植被和动态植被两种类型,讨论了两种类型包含的各种模型及其与流域水文模型耦合的研究进展。阐述了陆地生态系统模型与流域水文模型耦合在气候变化和人类活动影响研究中的重要意义,并分析了两者耦合研究的发展方向。