土地利用类型与水分亏缺的风险程度关系——以北方农牧交错带黄土高原区为例

在北方农牧交错带植被重建中适宜乔、灌、草种生态区划的基础上,以该区域黄土高原区作为研究区,结合该区1989和1999两年的土地利用分类图,通过计算区域缺水指数及对其分级,探讨了缺水指数在时间和空间上的变化规律,分析了耕地、林地、草地等该区主要土地利用类型在时间和空间上与缺水指数的关系。在此基础上,构建水分亏缺风险指数(RiskIndexofWaterDeficit),从研究区整体和各生态分区两个尺度上探讨了不同土地利用类型的RIWD时空分异。得出如下结论:①1989～2000年,研究区缺水指数均在中度以上,其变化幅度有逐年减少的趋势;②对比1989年和1999年两年的缺水指数,区域整体缺水状况有所缓解,但各生态分区内的缓解程度在空间上仍存在差异;③从研究区整体而言,各土地利用类型的水分亏缺风险指数逐渐减少,依次为林地、耕地、草地;④因各生态分区内的地理特征包括水分状况存在变化,故各土地利用类型的水分亏缺风险程度排列顺序与区域整体有所不同。     

徐州张集水源地裂隙岩溶水化学特征及影响因素

根据现场取样分析,对张集水源地裂隙岩溶水水化学特征进行了总结和分区,分析了其影响因素,提出了相应的环境保护措施.结果表明,裂隙岩溶水水化学类型一般为HCO3-Ca@Mg型及HCO3-Ca型,个别点出现HCO3@SO4-Ca型水,总体水质较好,存在局部污染现象;水源地裂隙岩溶水水质受含水层岩性和降水、地表水以及孔隙水越流等补给的影响,在制定水源地保护方案时应予考虑.      

污水流量测量中流量计的选型与探讨

环保产业对污水流量的测量和控制的精确度、可靠性要求已越来越高 ,介绍了电磁式、涡街式、节流式等几种流量计的选型设计 ,结合水处理工艺 ,从理论和实践两方面阐述各自的特点     

浅议砖厂对环境的破坏、污染及其防治对策

通过对哈密市40余家砖厂的调查和监测,分析了红砖生产对土地资源的破坏以及对大气环境造成的污染问题,就加强建设项目环境影响评价审批制度和排污申报登记、污染源监督监测工作,实行环境保护目标责任制,积极进行砖厂复坑复垦提出了必要的防治措施     

Impact assessment of a hydroelectric project on the flora in the Western Himalayan region based on vegetation analysis and socio-economic studies

This study provides an overview of the impacts of a proposed hydroelectric power project in the Western Himalayan region in India, using a primary database on floristic diversity and vegetation analysis. The remote sensing data revealed that in the submergence zone only mixed deciduous forest that occupies 807.5 ha area and has a wood biomass volume of 4,027,503 m³ is likely to be lost due to impoundment. A total of 165 plant species found in the submergence zone also occur in the influence and free draining catchment area of the project. In the influence zone of the project area only one tree species (Acer oblongum) is found under conservation threat category, which is also present in the free draining catchment of the project. The project affected population (6716 people) residing in the submergence and influence zone depend upon the surrounding forests for fuel wood, fodder, wild edibles etc., and most likely they will settle in the nearby areas, thus mounting more pressure on residual forests of the influence zone for various forest products. Further, from the vegetation analysis it is evident that several tree species (e.g. Lannea coromandelica, Terminalia alata, T. bellerica etc.), may face more pressure from exploitation as they provide a number of useful products and are represented in lower numbers in the forests of the project area. To compensate for the loss of various goods and services provided by the forests falling in the submergence zone and to offset the increased pressure of the project affected families on the forests of influence zone, a biodiversity management plan is suggested incorporating socio-economic considerations.     

Prenatal diagnosis of Crigler–Najjar syndrome type I by single-strand conformation polymorphism (SSCP)

Crigler–Najjar syndrome type I (CN-I) is a rare and severe inherited disorder of bilirubin metabolism, caused by the total deficiency of bilirubin-UDP-glucuronosyltransferase (UGT) activity. Enzymatic diagnosis cannot be performed in chorionic villi or amniocytes as UGT is not active in these tissues. The cloning of the UGT1 gene and the identification of disease-causing mutations have led to the possibility of performing DNA-based diagnosis. Here we report DNA-based prenatal diagnosis of CN-I in two Tunisian families in whom CN-I patients were diagnosed. As we had previously shown that CN-I was, in Tunisia, associated with homozygosity for the Q357R mutation within the UGT1 gene, we were able to detect this mutation in both families and to show that it was easily recognized by single-strand conformation polymorphism (SSCP) analysis. In both cases, SSCP analysis of fetal DNA showed that the fetus was heterozygous for the Q357R mutation. In one family, the pregnancy was carried to term and a healthy baby was born, whereas, in the other family, the pregnancy is still continuing. Thus the prenatal diagnosis of CN-I is possible, provided disease-causing mutations have been identified. SSCP analysis of DNA prepared either from amniocytes or from chorionic villi is a simple, reliable and fast method for prenatal diagnosis. Copyright © 2002 John Wiley & Sons, Ltd.     

双鸭山矿务局矿井伤亡事故分析和预防对策

根据双鸭山矿务局多年安全工作实践和４５ 年间数千次各类事故案例的经验教训，从中找出事故的发生趋势，发展规律和直接原因，并对今后如何超前防范提出了“三治”对策     

影响YYG-4B型冷原子荧光测汞仪诸因素分析

对YYG－4B型冷原子荥光测汞仪在测试中常出现的各种因素进行了分析探讨，提出了可行的解决方法，进一步提高了测定结果的精密度和准确度。     

上海市燃煤的现状分析及其污染管理措施

上海市以燃煤作为主要能源的工,商业大城市,大气污染以煤烟污染为主,燃煤排放的烟尘达到１９．８万ｔ／ａ,ＳＯ２为３９．６万ｔ／ａ;市区的燃煤密度相当高,在市区１３５个街道地区的燃煤密度＞２．０万ｔ／ｋｍ＾２·ａ,占２６％。为此,本文提出在实施近,远期环境保护规划时,应进一步加强监督管理措施,制定燃煤污染防治和定量管理目标考核方法,修订烟尘污染管理方法,并建议制定《上海市大气污染防治管理条例》。     

柳江盆地浅层地下水硝酸型水特征和成因分析

近年来地下水硝酸盐污染状况越来越严重,人类活动对地下水的影响加剧,不仅造成污染,甚至改变了地下水的水化学类型,出现了硝酸型地下水.本研究以柳江盆地为例,分析了该地区浅层地下水中硝酸型水的特征和影响控制因素,探讨了硝酸型水的研究意义.结果表明,柳江盆地浅层地下水中硝酸盐污染严重;在全区211组有效数据中,硝酸型水占比20.9%,主要分布在研究区东南部,北部山区分布较少且零散;根据硝酸型水的特征可将其划分为高TDS硝酸型水和低TDS硝酸型水,高TDS硝酸型水的TDS和总硬度浓度均较大,且浓度范围较广,低TDS硝酸型水的TDS和总硬度浓度值和浓度范围均较小;硝酸型水的形成主要受人类生活污水、农业施肥、化粪池和垃圾渗滤液下渗等影响,其中,高TDS硝酸型水的污染负荷通常高于低TDS硝酸型水;通过对硝酸型水的分析研究,能够尽早发现污染并不严重但已有污染趋势的区域,以便及时进行地下水的污染防治,避免水质进一步恶化.