Where,why, and to what extent have rangelands in the Karoo,South Africa,desertified

We used simple questionnaire surveys to obtain rough categorical information on the status of semiarid and arid rangelands in the Karoo, South Africa. We sent questionnaires to extension officers of the Department of Agricultural Development, asking them to rank the condition of the rangeland in their extension districts (usually about 500 farms) on a three- or five-point scale. The questionnaire also sought information on the possible reasons for changes in the condition of the rangelands; vegetation types most at risk on mismanaged rangelands; and changes in the status of plants, birds, and mammals. Extension officers rated 35% of the semiarid rangelands in southwestern South Africa (the Karoo and southern Kalahari Desert) as being in poor condition. There was some congruency between the perceived condition of the agricultural extension district and the percentage that the stocking rate had decreased. Rangeland condition in more arid areas tends to be poor. Stocking rates have decreased disproportionately more in arid areas than in the more mesic areas of southwestern South Africa. Grasses were rated as the most threatened group of plants, and succulents the least threatened group. Overgrazing in the past was considered to be the most important cause of present-day rangeland condition, followed by present overstocking of rangelands. Antelope were considered more threatened by rangeland management than mammalian carnivores. Avian raptors and bustards, gamebirds, and tortoises were all perceived to be threatened by rangeland mismanagement.     

地理信息学与煤矿环境管理

以地理信息系统，全球定位系统，遥感为主体和核心的地理信息学在煤矿环境管理中有着广泛的应用。本文在对地理信息学及其应用于煤矿环境管理的优点进行简要介绍和分析的基础上，对其在煤矿环境信息采集，监测，评价，治理等方面的应用进行了系统的探讨。     

矿区土地合理开发与利用研究

本文分析了矿区土地利用的特点，提出矿区土地合理开发与利用的原则，并对合理开发利用矿区土地的途径及其保障体系进行了研究。     

绍兴市城市工业生态规划转型的研究

环境与经济协调发展是当代各国面临的重大问题和挑战,生态工业是协调这一问题和挑战的重要战略,是可持续发展的基础之一.根据绍兴市以印染工业为主导、多种行业共同发展的产业结构,结合循环经济的理论和工业生态规划的原理和技术方法,来探讨绍兴市城市工业生态规划的转型模式,提出绍兴市工业结构调整的对策、生态工业网络体系的技术设计的策略以及生态工业园的产品链设计方案.绍兴市工业生态规划的转型是实现城市生态工业系统的有效可行的途径,是生态工业的集中体现.     

亚硝化-厌氧氨氧化组合工艺生物脱氮评介

本文阐述了亚硝化和厌氧氨氧化两种工艺的生物脱氮原理及研究现状，对亚硝化-厌氧氨氧化脱氮工艺和传统生物脱氮工艺从适用条件、曝气量、反应器容积、污泥产量等角度进行了分析和比较，为后续生物脱氮工艺的研究和选择提供借鉴，并展望了生物脱氮技术的发展方向和研究重点。     

蓄能器爆炸事故原因推断及防控措施

囊式蓄能器是液压系统中常用的压力容器。在更换胶囊和(或)充装氮气时如操作不当,有发生爆炸的风险。通过对一起蓄能器爆炸事故的调查,经计算、推论,得出此次爆炸是一起物理爆炸。并就事故发生原因及其爆炸强度、危害程度进行了分析。提出生产商和使用单位应制定科学的、可行的标准操作程序(Standard Operation Program,SOP),并要求工人在实际操做中严格执行,加强过程控制,避免事故的发生。     

计算机类学生编程素质的培养

针对计算机类学生在软件编程中出现的问题，本文就格式化编码、界面设计的一致性和清晰性、错误报告的方式与时机、交互二重性等方面进行了细致的介绍，以Visual Basic 6．x为编程语言提出了相应的解决办法，对提高计算机类专业学生的编程素质有较强的指导意义，对其他软件开发或程序设计人员也有较高的借鉴价值。     

Optimizing the configuration of a clearwell by integrating pilot and full-scale tracer testing

In this paper, the main factors impacting the plug flow pattern of a clearwell were investigated by integrating pilot-scale, full-scale clearwell tracer testing and computational fluid dynamics (CFD) simulation. It was found that pilot tracer testing, full-scale tracer testing and CFD simulation all demonstrated that the correlation between the ratio of t ₁₀/T and L/W can be approximately expressed by: t ₁₀/T = 0.189 4ln(L/W)-0.049 4. This study confirmed that the installation of baffles within clearwells is an efficient way to optimize their configuration. In addition, the inlet velocity has a minimal contribution to the ratio of t ₁₀/T. However, the ratio of turning channel width to channel width (d/W) significantly contributes to the ratio of t ₁₀/T. The optimal ratio of d/W is 0.8–1.2 for maintaining better plug flow pattern. The number of turning channels is one of the main factors that impact the ratio of t ₁₀/T. When increasing the number of turning channels, a lower ratio of t ₁₀/T is obtained.     

羊草和大针茅光合作用午间降低与生态因子关系的研究

本项研究指出,在晴天条件下,由于土壤水分含量不同,羊草和大针茅的光合作用日进程呈现出两种类型:在土壤水分充足时,为午前高峰型;在土壤干旱时,为双峰型。两者均属于光合作用午间降低的类型。 两种植物相比,在土壤干旱时,羊草比大针茅光合午间降低幅度大得多;在土壤水分充足时,其降低程度相近。无论土壤含水量高低,大气湿度降低均是引起光合午间降低的主要大气生态因子。所不同的是,强光只有在土壤干旱时才是引起光合午间降低的直接生态因子;因此,午后光合高峰的出现是光强下降所致。土壤水分亏缺与大气低湿相配合,加剧了光合午间降低的程度,其降低幅度随着土壤水分的减少而增大。因此,增加土壤水分是减缓光合午间降低程度的主要生态途径。     

大理西湖水质变化趋势分析

通过对１９９１－１９９５年大理州西湖水质监测资料的分析，研究了西湖水质现状及其变化趋势。同时，应用灰色关联度模型对其富营养化进行了评价，并提出防治措施及建议。