Assessing land use impacts on flood processes in complex terrain by using GIS and modeling approach

A distributed hydrologic modeling and GIS approach is applied for the assessment of land use impact in the Steinsel sub-basin, Alzette, Grand-Duchy of Luxembourg. The assessment focuses on the runoff contributions from different land use classes and the potential impact of land use changes on runoff generation. The results show that the direct runoff from urban areas is dominant for a flood event compared with runoff from other land use areas in this catchment, and tends to increase for small floods and for the dry season floods, whereas the interflow from forested, pasture and agricultural field areas contributes to the recession flow. Significant variations in flood volume, peak discharge, time to the peak, etc., are found from the model simulation based on the three hypothetical land use change scenarios.     

Pool of Dust Particles over the Asian Continent: Balloon-borne Optical Particle Counter and Ground-based Lidar Measurements at Dunhuang, China

Measurements of aerosols were made in 2001 and 2002 at Dunhuang (40 degrees 00'N, 94 degrees 30'E), China to understand the nature of atmospheric particles over the desert areas in the Asian continent. Balloon-borne measurements with an optical particle counter suggested that particle size and concentration had noticeable peaks in super micron size range not only in the boundary mixing layer but also in the free troposphere. Super-micron particle concentration largely decreased in the mid tropopause (from 5 to 10 km; above sea level, a.s.l.). Lidar measurements made during August 2002 at Dunhuang suggested the possibility that mixing of dust particles occurred from near the ground to about 6 km even under calm weather conditions, and a large depolarization ratio of particulate matter was found in the aerosol layer. The top of the aerosol layer was found at heights of nearly 6 km (a.s.l.). It is strongly suggested that nonspherical dust particles (Kosa particles) frequently diffused in the free atmosphere over the Taklamakan desert through small-scale turbulences and are possible sources of dust particles of weak Kosa events that have been identified in the free troposphere not only in spring but also in summer over Japanese archipelago. Electron microscopic experiments of the particles collected in the free troposphere confirmed that coarse and nonspherical particles observed by the mineral particle were major components of coarse mode (diameter larger than 1 microm) below about 5 km over Dunhuang, China.     

几种土壤质量评价方法的比较

分别用Ｔ值分级法，综合指数法，模糊数学综合评判法，灰色聚类法，等斜率灰色聚类法，宽域灰色聚类法对湖南某地１０个监测点的土壤质量现状进行评价，通过比较，认为宽域灰色聚类法较好。     

助催化无汞盐快速测定水中化学需氧量

在ψ（Ｈ２ＳＯ４）＝５６％硫酸介质，重铬酸钾的氧化体系中，以钼权铵，硫酸铝钾为助催化剂，可减少量化剂硫酸银的用量，消解１５ｍｉｎ即可测定水中化学需氧量，用硝酸银溶液代替硫酸汞去除水氯离子，避免了汞盐的污染，工业废水回收率在９７％～１０１％之间，有较好的准确度。     

环境中萘和甲基萘的气相色谱测定

针对发生的甲基萘油车泄漏事故进行了水样和空气样品中萘和甲基萘的测定，水样中直接进样，对空气样品则以甲醇为吸收液吸收，富集，氢火焰毛细管色谱法测定。     

沙湾荒漠区生态环境的植物监测

利用植物生态学常规方法进行了荒漠植被种群生物量和数量特证调查,以植物为监测对象,并就群落地上部分生物量,Shannon-Wiener多样性指数,群落均匀度,生态优势度等指标探讨了在荒漠生态环境监测和评价中的具体应用。     

土壤全氮的快速测定

本方法是过硫酸盐氧化消化样品的基础上测定土壤中全氮的光度法.采用碱性过硫酸钾溶液(0.37mol/L K_2S_2O_3,0.375N NaOH)消化土壤样品,然后用百里酚光度法进行测定,具有准确、灵敏、快速、简便等优点,适用于常规和大量样品的分析.     

超声波萃取-高效液相色谱法测定总悬浮颗粒物中的多环芳烃

研究了一种用中流量采样器采样,超声波萃取,硅镁型吸附剂柱层析预分离.高效液谱测定总悬浮颗粒物的实验方法,在16分内可分高萘、蒽、芘、苯并(a)芘、苯并(ghi)苝等15种多环芳烃.已在大气环境的实际监测中得到应用.     

污染土壤的植物修复技术进展

植物修复技术是通过使用绿色植物修复污染土壤。它主要源于一系列农艺学，生物学和工程学技术，利用影响植物的生物、微生物及植物的化学和物理作用复污染场地，标签昨技术在经济，美学和技术方面比传统的工程修复技术有更大的优点，概述了植物修复领域的研究动向，以便为修复工作者提供背影资料和研究方法。     

Adsorption of zinc on manganite(γ-MnOOH): particle concentration effect and adsorption reversibility

The adsorption and desorption processes of Zn(Ⅱ) on τ-MnOOH as a function of particle concentrations (Cp) were studied. An obvious Cp effect was observed in this adsorption system. The degree of adsorption hysteresis increased greatly with the increasing of Cp, indicating that the extent of the real metastable-equilibrium states deviating from the ideal equilibrium state was enhanced with the increasing of Cp. The Cp-reversibility relationship confirmed the metastable-equilibrium adsorption (MEA) inequality (Pan, 1998a), which was the core formulation of the MEA theory. Because the MEA inequality was based on the basic hypothesis of MEA theory that adsorption densitιy ι is not a state variable, the Cp-reversibility relationship gave indirect evidence to the basic hypothesis of MEA theory.