云南地区种子植物区系属的多度及区系过渡性的空间分布格局

植物区系地理分布格局的研究有助于更好地理解植物区系的起源、迁移和分化。研究利用覆盖云南地区全境的植物区系分布信息,探讨了云南地区植物区系属的多度及区系过渡性的地理分布格局。结果表明,所有热带区系属的多度均随着纬度升高呈递减趋势;大多数温带区系属的多度随着纬度的升高呈递增趋势。中亚分布(T13)属的多度的高值主要出现在滇西北地区,尤其是在金沙江、澜沧江和怒江的上游地区,但在其它地区十分少见。地中海、西亚至中亚分布(T12)属的多度的高值也出现在滇西北地区,但在其它地区无明显空间分布规律;中国特有分布(T15)属在滇西北地区最为丰富,其次是滇东南地区,大致以"田中线"为界,界线以西地区的中国植物特有属的多度明显低于界线以东地区。从南到北,植物区系过渡性基本上呈单调递增格局,这一格局的形成可能与区系成分的迁移和地形格局有关。大理州以南的低海拔地区,热带区系成分占据主导地位,并占据了云南大部分的土地面积,这在一定程度上证实了云南地区总体上是一个"热带山原"的假说。本研究与其它研究的不同可能源于与源数据和取样尺度的差异。     

磷酸三(2,3-二氯丙基)酯暴露诱发NRK-52E细胞纤维化的体外研究

自2004年禁止使用五溴联苯醚混合物阻燃剂以来,有机磷阻燃剂(organophosphorus flame retardants,OPFR)作为替代品开始被广泛生产和使用,因而成为当今阻燃剂研究的热点。目前,有机磷阻燃剂在水体环境及生物体中已有较高的检出率,而其对生物体及生态环境的潜在毒性效应还知之甚少。本研究利用磷酸三(2,3-二氯丙基)酯(tri(2,3-dichloropropyl)phosphate,TDCPP)对大鼠肾小管上皮细胞(NRK-52E)的毒性暴露实验,探讨TDCPP潜在的肾脏毒性。结果表明:一定剂量的TDCPP对NRK-52E的细胞活性有抑制作用,能诱导细胞内活性氧自由基(reactive oxide species,ROS)生成量增加,并触发上皮-间充质转换(epithelial-mesenchymal transition,EMT)及胞外基质沉积因子如波形蛋白(vimentin)、转化生长因子-β1(transforming growth factor-β1,TGF-β1)、胞外基质成分纤连蛋白-1(fibronectin-1,FN-1)等基因mRNA表达的显著上调以及上皮细胞钙粘蛋白(E-cadherin)等基因mRNA表达的显著下调。上述研究结果表明,TDCPP可促进NRK-52E细胞发生上皮间充质转化及纤维化。本研究为进一步综合评估TDCPP的生物和环境毒理效应提供了基础实验数据。     

转型期城市旅游业绩效评价及空间格局演化机理——以泛长江三角洲地区为例

论文从经济、市场、效率、公平四个方面构建了旅游业绩效的评价体系,运用熵值法综合测度1998、2003、2008年泛长江三角洲城市旅游业绩效,并结合GIS的空间分析模块,系统分析了泛长江三角洲城市旅游业绩效空间格局的演化过程。结果表明:泛长江三角洲城市旅游业绩效空间分异明显,总体上呈现提高态势,3个时间断面均呈现东西方向递增,南北方向倒"U"型分布格局;相邻地域单元表现较弱的空间集聚特征,绩效系统内部整体协调度不强,部分城市旅游业绩效水平与协调度高度耦合;针对旅游业绩效区域差异格局演化的形成机理剖析表明,经济驱动、市场驱动、产业链驱动、政府驱动及其相互间的综合驱动共同作用促使了城市旅游业绩效空间格局的演化。     

Cross‐sectional epidemiological study on the lead burden of children and workers in Greece

Exposure of the general population to lead in the environment is mainly caused by motor traffic exhaust and by industrial pollution. The aim of the study in Greece was to assess lead exposure in children living in point source impacted areas (Lavrion and Aspropyrgos‐Eleusis) using the biological monitoring parameter “blood lead concentration”;.

In addition, workers of a lead smelter, a battery plant and an oil refinery were investigated in these areas at the same time.

Five hundred and thirty‐four children and 105 workers took part in this investigation.

The highest blood lead levels (mean: 24.16 μg/100ml; range: 10.40–60.49 μg/100 ml) were found in children living in a 500m‐area around the lead smelter at Lavrion. Blood lead decreases corresponded to the increasing distance from the emitter. Nevertheless the values of children living in a 1500 m distance to the smelter are significantly higher than those of children living next to other kinds of industrial lead sources.

The mean values of the children living in the two industrial towns were manifold higher than those of the control group.

The blood lead levels of the investigated workers did not exceed the German BAT‐value (Biologischer Arbeitsstoff‐Toleranzwert) of 70 μg/100ml.     

Cu(Ⅱ)、Fe(Ⅲ)和Cr(Ⅲ)在弱酸性条件下对大肠杆菌的毒性和致毒机制

比较了弱酸性条件下Cu(Ⅱ)、Fe(Ⅲ)和Cr(Ⅲ)单独或加入抗坏血酸(L-AscA)对大肠杆菌(E.coli)的毒性,深入分析了Cu(Ⅱ)/L-AscA体系的特性;通过电子自旋共振(ESR)定量分析羟基自由基(.OH)浓度以分析其毒性机理.结果表明,pH 4.0下L-AscA促进了Cu(Ⅱ)、Fe(Ⅲ)而非Cr(Ⅲ)的毒性,三者毒性Cu(Ⅱ)>Cr(Ⅲ)>Fe(Ⅲ).通常被认为无毒的Cr(Ⅲ)却在0.2 mmol.L-1,pH 4.0时表现出了很高的杀菌率.与0.01%L-AscA共存时,Cu(Ⅱ)为200、20μmol.L-1和2、0.2μmol.L-1下,E.coli的存活率分别在30 min和2 h内迅速降至零,且该体系对自然水体中分离所得的其它7种菌株同样具有明显的制御作用.ESR结果表明L-AscA的加入使200μmol.L-1Cu(Ⅱ)反应体系的.OH浓度约提高两倍,.OH浓度呈Cu(Ⅱ)浓度依赖.但在Fe(Ⅲ)、Cr(Ⅲ)/L-AscA体系中未检测到.OH,表明三者对细胞的致毒机制存在明显差异.     

基于两种耦合方法的模拟-优化模型在地下水污染源识别中的对比

采用一种基于模拟-优化模型的方法对地下水污染源进行识别研究.模拟-优化模型分别采用响应矩阵法和状态转移方程法进行耦合,并利用遗传算法求解,经过多次迭代,使得模拟结果与观测数据的误差达到最小.最后,通过一个假想例子评估模拟-优化模型的性能,同时比较应用不同耦合方法的计算结果.研究表明:应用响应矩阵法耦合模拟-优化模型所得结果的绝对误差范围为0.1~1.6g/L,应用状态转移方程法时,绝对误差范围为0~5.2g/L,因此,采用遗传算法求解模拟-优化模型能够有效且准确地得到地下水污染源的释放量,可以应用于地下水污染源识别问题,并且采用响应矩阵法耦合模拟-优化模型优于状态转移方程法.     

From Management to Mediation: Local Forestry Management and the Forestry Crisis in Post-Socialist Russia

The local branches of the Russian Forestry Service, the leskhozy, were known for their efficiency and management skills in the Soviet era and were one of the very few community-based Soviet-type institutions to survive the transition. This article examines the role of the leskhozy in the new market economy. Our analysis is based on data from interviews with informants attached to the forestry sector in the Murmansk area. In some cases their knowledge of the leskhozy stretches back to the emergence of the system in 1947. Our principal finding is that the struggle to survive as a federal body in the current legal and economic climate is forcing the leskhozy to relegate sustainable forestry management, presumably their primary raison dêtre, to the lower portions of their list of priorities. Several consequences result. There is a heightened incidence of illegal logging, and corruption informs the allocation of forest areas to private interests. Stumpage prices have plummeted as timber from subsidized commercial cutting (ostensibly sanitary cutting or thinning) has flooded the markets. The root cause of these tribulations lies with the market-based harvesting permit system. Its introduction in the 1990s did little to eliminate the self-seeking practices of the old Soviet forestry management hierarchies. In the free market, local forestry managers can turn their dual responsibilities to their own advantage inasmuch as they control the allocation of harvesting permits while at the same time controlling logging practices.     

A transition in the Dutch wastewater system? The struggle between discourses and with lock-ins

ABSTRACT

Recently, calls have increased for a paradigm shift or transition towards resource recovery and a circular economy in the Dutch wastewater system. However, we have observed diverging interpretations on the nature of the transition. This reflects the political environment of sustainability transitions: political struggle emerges over the definition of problems, futures and strategies to be used. In order to help clarify the emerging debate and identify political choices, we conducted a discourse analysis. We identified three discourses that reveal some of the political choices to be made. One discourse is becoming dominant and focusses on optimising the large-scale infrastructure, market development and legislative changes. The discourse draws on the existing infrastructure and current political-economic institutions, which gives it an advantage in becoming dominant. Our findings also suggest that this discourse shapes a transition pathway that is characterised by lock-in effects and, at most, incremental changes instead of a fundamental shift in the established Dutch wastewater system.     

Exposing violences: Using women's human rights theory to reconceptualize food rights

Exposing food violences – hunger,malnutrition, and poisoning from environmentalmismanagement – requires policy action thatconfronts the structured invisibility of theseviolences. Along with the hidden deprivation offood is the physical and political isolation ofcritical knowledge on food violences and needs,and for policy strategies to address them. Iargue that efforts dedicated on behalf of ahuman right to food can benefit from thetheoretical analysis and activist work of theinternational Women's Rights are Human Rights(WRHR) movement. WRHR focuses on women andgirls; the food rights movement operates onbehalf of all people, with an emphasis on thepoor. Both attend to the protection of bodilyintegrity against physical and psychicviolences. Both cope with bodily violences thatare socially privatized and spatiallysegregated from public institutions of relief,that is, they are tacitly omitted from publicdiscourse and purview. Most typically, but notexclusively, these violences unfold in privatehousehold space. Both rights movements mustmobilize political rights to demand economicand social rights and security. I introduce theUnited Nations' early Declaration (1948) andCovenant (1966) language on the human right tofood and review problems of household accessand grassroots engagement that are ``writteninto' this early documentation. An abbreviatedoverview of the WRHR movement describes how thepublic/private and economic/political rightsdichotomies have been critiqued andre-formulated. A case study set in Polandacross the transition from (more) communist to(more) capitalist political economies attemptsto illuminate the discussion through agrounded example.     

Refuting the paradigm of water services privatisation

The aim of this article is to question the fundamental assumptions behind privatisation and public–private partnerships. The article shows that instead of radically increasing private sector involvement, public sector reforms should be seriously considered. Public–private partnerships should be implemented so that the strengths of all the stakeholders may be fully utilised.