Mekong River Fish Conservation Zones in Southern Laos: Assessing Effectiveness Using Local Ecological Knowledge

Small-scale fisheries are important in Laos, where rural people heavily depend upon Mekong River and tributary fish stocks for their livelihoods. Increasing pressures from human exploitation and habitat disturbance, however, have raised serious concerns about the potential depletion of various species. This has led to the establishment of large numbers of Fish Conservation Zones (FCZs) or “no-take” fish sanctuaries in southern Laos based on a “community-based fisheries co-management” framework. This study uses the local ecological knowledge (LEK) of fishers to assess the effectiveness of village-managed FCZs in enhancing fish stocks in the mainstream Mekong River in Khong District, Champasak Province. Focus group interviews about species that are believed to have benefited from different FCZs are compared with parameters such as FCZ area, age, depth, localized gradient, water velocity, and the presence of wetland forests nearby. The results suggest that no one aspect is likely to account for variations in fish stocks; rather, it is the interaction between numerous factors that has the largest impact. Secondly, the results indicate that microhabitat diversity and protection are critical for maintaining and enhancing Mekong fisheries. Deep-water pools are particularly important as dry season refuges for many fish species, and FCZ depth may be the single most important environmental factor affecting the success of FCZs in the Mekong River. FCZs have the most potential to benefit relatively sedentary species, but may also benefit highly migratory species, given the right conditions. This study shows that integrated approaches to stock assessment that employ LEK and scientific fisheries management have considerable potential for improving Mekong capture-fisheries management.     

不同预处理对纳氏试剂比色法测氨氮的影响

用纳氏试剂比色法测污水中氨氮含量,为了消除干扰物质对测定的影响,需根据水体受污染程度,对水样通过絮凝沉淀法或蒸馏法进行预处理.本文通过试验论证了即使对较清洁的水,也以蒸馏法预处理为佳,蒸馏法预处理后的测定值更接近真值.     

西部地区重大工程建设中的泥石流灾害 --兼论其与环境的互馈作用

在西部大开发过程中,许多重大工程建设涉及泥石流灾害的问题.讨论了工程活动、泥石流及山地环境之间的相互作用和影响.工程活动往往受到泥石流、山地环境的制约,同时它作为活的因素,又积极地影响着泥石流和山地环境,促使其产生次生演化,泥石流和山地环境的次生演化常会对工程活动产生次生制约.泥石流的发生会危及工程和人类的安全,破坏地表,破坏生态环境;人类工程活动若不遵守自然规律,过度向山地索取,必将导致山地环境退化和泥石流的广泛活动及频繁发生,甚至引起泥石流活动范围扩大和成灾规律改变.     

广西农业干旱及水资源合理开发利用

分析了广西农业干旱形成的原因和干旱的时空分布特征;采用降雨量、受旱面积、有效灌溉面积及年径流量,制定出干旱指数、受旱系数、耕灌比系数和水资源利用系数,并依照上述4项指标将广西划分为3个农业干旱区,对各旱区的气候特点、年径流量和水资源利用情况进行了较为详尽的分析.广西水资源丰富,但利用率较低,因此为了提高广西的水资源利用率,应加强水利建设,推广科学灌溉,加大地下水开采.     

Improvements in Air Quality Modelling by Using Surface Boundary Layer Parameters derived from Satellite Land Cover Data

Many atmospheric dispersion models include only simpletreatment of surface features to estimate the wind profilesand stability parameters. Detailed characterisation of theland cover, particularly in large and complex urbanconurbations, is especially important, as the surfacefeatures can vary significantly over the area. This paperdiscusses the use of satellite land cover data to derivespatially resolved surface boundary layer (SBL) parameters.These parameters have been used in an air quality model,PEARL (Prediction Air Quality in Urban and RegionalLocations) for estimating monthly and annual COconcentrations. Land cover data, derived from LANDSATThematic Mapper Imagery, has been used to estimate SBLparameters (surface roughness length, albeedo, Bowen ratioand anthropogenic heat flux) for a study area of 10000km² encompassing Greater London and the surroundingcounties. The SBL parameters have been assigned according tomajor land cover types for the whole area at a spatialresolution of 1 × 1 km. Predictions from two versions of the PEARL model (one with land cover data and one without)have been compared with each other and with measured data forannual and monthly CO concentrations from seven London airquality monitoring sites. This comparison shows thatdifferences between predicted and observed values can bereduced by up to a factor of three. The use of SBLparameters derived from land cover data also yields moredetailed predicted annual CO spatial patterns especially inand around suburban areas. The performance of both versionsof the model for monthly CO concentrations has been comparedwith a range of statistical measures. This comparisonconfirms that improved agreement is observed betweenmodelled and measured monthly CO concentrations when use ismade of spatially resolved SBL parameters.     

用三性法对巴楚伽师6.8级地震的跨越式预测

介绍了用三性法对2003年2月24日新疆巴楚伽师6．8级地震的早期跨越式预测，并讨论了某些相关问题。所谓三性法就是大震时序上的周期性、倍周期性和黄金分割性的排列。     

太阳活动对地球表面温度影响的研究进展

论述了近年来对地球表面温度变化特征、原因研究的意义及研究进展。许多研究表明，20世纪全球地表气温的变化是自然因素和人为因素共同作用的结果。根据多种反映太阳活动的代用指标拟合的气候模型指出，太阳活动可以解释1850年以前气温变化的大部分情况。工业革命以来，温室气体成为不可忽视的影响因素，太阳活动对气候影响所占的比重及其相互作用的物理机制仍然是有待深入研究和解决的问题。     

Comparison between controlled landfill reactor and conditioned landfill bioreactor

Bioreactor landfills allow a more active landfill management that recognizes the biological, chemical and physical processes involved in a landfill environment. The laboratory-scale simulators of landfill reactors treating municipal solid wastes were studied, the effect of solid waste size, leachate recirculation, nutrient balance, pH value, moisture content and temperature on the rate of municipal solid waste (MSW) biodegradation were determined, and it indicated the optimum pH value, moisture content and temperature decomposing MSW. The results of waste biodegradation were compared with that of the leachate-recirculated landfill simulator and conservative sanitary landfill simulator. In the control experiment the antitheses of a decreasing trend of the organic load, measured as biological oxygen demand and chemical oxygen demand, was shown. An obvious enhancement of effective disposal from conservative sanitary landfill (CSL) simulator, to the leachate-recirculated landfill (LRL) simulator and to the conditioned bioreactor landfill(CBL) simulator would be noted, through displaying the compared results of solid waste settlement, heavy, metal concentration in leachate, methane production rate, biogas composition, BOD and COD as well as their ratio.     

农村居民点土地整理研究--以芜湖市为例

农村居民点土地整理是近几年来产生的一种新型的农村土地整理形式，其研究尚处于不成熟阶段。运用定性与定量相结合的方法对农村居民点土地整理工作前期的几个理论要点，即土地整理的必要性、可行性以及效益等，并结合芜湖市农村居民点的具体情况进行了详细的分析论述。其研究成果不但有助于我国土地整理事业的发展，而且可为其它地区的农村居民点土地整理工作提供一定的理论基础。     

寒冷地区化粪池的效果评价和探讨

寒冷地区化粪池具有水温低,处理效果差的特点,针对哈尔滨市幸福家园化粪池的水质情况进行了研究,为化粪池的改造和优化提供依据,并对化粪池问题和技术进行探讨。在化粪池前后的检查井处进行取样,每隔1个小时取一个样,总共取24小时,然后对CODtot、CODss、CODcol、CODdis、NH3-N、总氮、总磷、SS、VSS、pH、水温进行测定。水温在14～17度下,平均去除率分别是16.9%、47.2%、26.4%、-49.1%、-39.3%、7.5%、12.4%、59.3%和59.5%,可见,污水的可生化性有明显提高,但是对污染物的去除作用不大。研究结果对于全面评价寒冷地区化粪池的功能特征,进而为化粪池的取舍和改造提供技术的参考依据。