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101.
亚洲地区环境监测实验室精度调查   总被引:1,自引:0,他引:1  
为了解亚洲各国环境监测实验室监测分析数据的精度现状,提高实验室的监测技术水平,同时为了编制“亚洲地区环境监测实验室精度管理手册”提供依据,日本JICA(日本国际协力团)在亚洲开展了精度调查工作。文章报导了我国有关的33个环境监测实验室参加该精度调查的内容,和本次精度调查的结果及影响数据质量的因素分析,并与亚洲其它国家精度调查结果进行了比较。  相似文献   
102.
北京及近中国海春季沙尘气溶胶浓度变化规律的研究   总被引:14,自引:0,他引:14  
对北京和近中国海气溶胶观测资料的统计分析表明,沙尘气溶胶浓度呈现显的年示变化,该变化与沙尘源区及主要输送通道上的气象条件密切相关。运用多元线性回归分析结合气溶胶观测资料和气象资料计算了北京春季沙尘气溶胶家度。结果表明1971-1995年北京春季沙尘气溶胶浓度总体呈递砬趋势,但进入九十年代,这种递减趋势有所减缓。  相似文献   
103.
粤东花岗岩类的SiO_2、K_2O及ALK值偏高,Al_2O_3、Fe_2_O_3、FeO及MgO偏低,ANKC值、Na/K比及CaO、Na_2O含量介于华南改造型花岗岩和同熔型花岗岩之间;负铕异常明显,轻稀土显著富集,中稀土(Tb—Tm)略有亏损;铅同位素高于地幔铅和下地壳铅同位素组成,略低于华南中生代上地壳铅同位素组成;锶、氧同位素具正相关关系,不相容元素比与其他元素间无相关关系。其岩浆起源于上、下地壳间的过渡带,该过渡带由上地壳物质及侵入其中的幔源物质组成,岩浆上升定位过程中,未发生过明显的分异结晶一同化作用。  相似文献   
104.
以武汉市东湖风景区为例,建立旅游环境容量指标体系,研究相关环境容量计算方法,最终得出各景区不同水质环境下的旅游环境承载率,并提出采取点源截污、面源污染控制和生态修复等措施。  相似文献   
105.
超微型浮游藻类(3μm)主要包括超微蓝藻(PCY)和超微真核藻(PPEs),是浮游生态系统的重要组成部分,在水体物质循环和能量流动中起着重要作用.为了解通江湖泊中超微藻动态变化特征及其关键影响因子,于2019年洞庭湖丰水期(5~8月)每月对东洞庭湖进行采样调查,研究了丰水期间东洞庭湖超微藻生物量和丰度的时空演变规律及其与环境因子的关系.结果表明,东洞庭湖丰水期超微藻生物量和丰度均表现出显著的时空演变规律(P0.05).整个丰水期间,超微藻Chla平均浓度为8.52μg·L~(-1),其对总浮游藻类Chla的贡献率平均为41.6%;从5~8月,随着水温的增加,超微藻Chla浓度不断增加,尤其是东洞庭湖北部湖区和南部湖区;东部行洪道超微藻Chla浓度全湖最低.PCY是东洞庭湖超微藻的主要优势藻,其丰度平均是PPEs的3.4倍.PCY和PPEs丰度表现出相似的时空分布规律:时间上,从5~8月均呈现先增加后降低的趋势;空间上,随着丰水期的推移,超微藻丰度峰值由北部湖区向南部湖区迁移,到8月丰水期末期超微藻丰度逐渐降低,北部湖区超微藻丰度最高.分析结果表明,丰水期超微藻表现出了显著的时空分布规律,水位和N∶P比是影响东洞庭湖PCY和PPEs丰度组成比例变化最重要的因子.  相似文献   
106.
“八五”至“十二五”期间,中国取得巨大的经济成果的同时带来了严重的水环境污染问题.文章分析了东中西部三大经济带经济发展及COD和氨氮两种主要水污染排放的差异,及其与经济发展的关系进行了EKC假说的实证研究.研究结果表明,部分污染物的拟合曲线尚处于上升阶段,未能出现典型的倒U型曲线,可能导致水环境质量恶化.环境基础设施建设、人口分布和产业结构等因素与COD和氨氮的排放量密切相关,因此,中国必须采取各种环境管理和技术手段,促使区域水污染物排放量指标与经济发展的拟合曲线出现转折点,改善水环境质量.  相似文献   
107.
Agriculturally altered vegetation, especially oil‐palm plantations, is rapidly increasing in Southeast Asia. Low species diversity is associated with this commodity, but data on anuran diversity in oil‐palm plantations are lacking. We investigated how anuran biological diversity differs between forest and oil‐palm plantation, and whether observed differences in biological diversity of these areas is linked to specific environmental factors. We hypothesized that biological diversity is lower in plantations and that plantations support a larger proportion of disturbance‐tolerant species than forest. We compared species richness, abundance, and community composition between plantation and forest areas and between site types within plantation and forest (forest stream vs. plantation stream, forest riparian vs. plantation riparian, forest terrestrial vs. plantation terrestrial). Not all measures of biological diversity differed between oil‐palm plantations and secondary forest sites. Anuran community composition, however, differed greatly between forest and plantation, and communities of anurans in plantations contained species that prosper in disturbed areas. Although plantations supported large numbers of breeding anurans, we concluded the community consisted of common species that were of little conservation concern (commonly found species include Fejervarya limnocharis, Microhyla heymonsi, and Hylarana erythrea). We believe that with a number of management interventions, oil‐palm plantations can provide habitat for species that dwell in secondary forests. Efectos de las Plantaciones de Palma de Aceite sobre la Diversidad de Anuros Tropicales Faruk et al.  相似文献   
108.
Abstract:  With about half the world's human population and booming economies, Asia faces numerous challenges to its biodiversity. The Asia Section of the Society for Conservation Biology has identified some key policy issues in which significant progress can be made. These include developing new sources of funding for forest conservation; identifying potential impacts of energy alternatives on the conservation of biodiversity; curbing the trade in endangered species of plants and animals; a special focus on the conservation of mountain biodiversity; enhancing relevant research; ensuring that conservation biology contributes to major international conventions and funding mechanisms; using conservation biology to build a better understanding of zoonotic diseases; more effectively addressing human–animal conflicts; enhancing community-based conservation; and using conservation biology to help address the pervasive water-deficit problems in much of Asia. These challenges can be met through improved regional cooperation among the relevant stakeholders .  相似文献   
109.
This paper highlights current trends in consumption and production patterns in Asian developing countries and emerging economies. It describes the main challenges and opportunities for Asian countries making the transition towards sustainable consumption and production patterns. The main challenge for Asian economies is to address the unsustainable consumption patterns of urban consumers, which entails a policy shift from the current focus on pollution and inefficient industrial production. In view of future consumption trends and the global convergence of consumption patterns, the characteristics of the emerging 'global consumer class' are examined, with particular focus on urban ecological footprints and carbon emissions. Furthermore, the difference between urban and rural consumption is discussed, together with opportunities for low-carbon urban development in the megacities of Asian developing countries. To conclude, the paper presents an overview of current policy measures taken in Asian countries to green economic development and realise sustainable consumption and production patterns.  相似文献   
110.
This study investigates the distributions and enrichments of trace metals in suspended and sinking particulate matter from southern East China Sea (ECS) north of Taiwan during the period April 1992 to April 1993. According to these results, concentration of suspended particulate matter in the inner shelf of southern China Sea, the upwellinginfluenced shelf break, and in Kuroshio water are 1.30 (surface)-4.2 (bottom) mg1-1, ca. 0.4 mg1-1 and 0.1-0.2 mg1-1, respectively, reflecting various influences of terrestrial inputs. A benthic nepheloid layer (BNL), apparently owing to resuspension of local and/or remote bottom sediments, formed over the shelf region. Temporal variations in trace metal contents and enrichments in suspended matter from the shelf region reflect the variation of metal inputs from Chinese rivers, particularly from the Changjiang runoff. the enriched metals are more likely to be derived from anthropogenic input, rather than from biological accumulation. in addition, a decrease in metal contents and an increase in salinity confirm the transport of suspended particulate metals from the East China Sea shelf to the open ocean. the feature of metal plume in the intermediate layer (550-800m) of Kuroshio water also verifies this occurrence. Moreover, the sinking particles collected from a sediment trap on the upper slope are relatively enriched in lithogenic matter and trace metals, suggesting the deposit of anthropogenic metals in the slope area.  相似文献   
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