Vegetation patterns and nature reserve construction in an extremely-arid desert in Anxi,NW China's Gansu Province

Anxi County is located in the northwestern part of the Hexi Corridor in gansu Province and has the sole national level nature reserve of extremely-arid desert in China.Phytosociological methods (Braun-Blanquet,1964) are used to classify plant community types in this area.Eleven are disting uished,including six of deserts,four of oases and one transitional type between deserts and oases.Direct gradient analysis (DCA) is employed to correlate the distribution of plant communities to physiogeographic conditions.This study makes clear that water is the most important ecological factor for the distribution of plant species and communities in this area.The effects of water have been demonstrated in different ways.A vegetation gradient from lower altitude to higher altitude in the southern part of the reserve is driven by a precipitation gradient.The effects of the depth of ground water table contribute to the differentiation of vegetation from desert to oasis in the flat area.In a finer scale,the washed gullies have obviously higher species richness and also higher vegetation cover than the surround gobi surfaces,possibly caused by the effects of floods.The vegetation patterns demonstrate that the area of Anxi County is a complete landscape unit.The range of the current nature reserve is not large enough for the purpose of conserving the unique biodiversity in this area.     

城市电磁辐射污染评价─—功率密度传播模型

通过厦门和漳州两城市电磁辐射测试研究，给出城市电磁辐射功率密度传播模型。提出按传播模型，取少量测试点实测数据，用“三点逐进估算法”计算，得出整个城市人口暴露评价的方法。     

高浓度农药废水的治理方法介绍

通过对佳木斯农药三厂污水治理技术的研究 ,介绍一种先进的农药废水处理方法及实用技术。     

自然·水·人

人类社会向前发展,人向自然界的索取不断增加,对自然的干扰也逐步加剧,致使自然界的承受能力受到影响,人与自然的关系出现紧张。为此,人必须处理好与自然的关系,以免人的生存环境受到威胁。水是自然界的重要因素,和人的生存与人类社会的发展关系密切。由于用水量不断增加和用水不当,一些地区出现水资源危机,人在和水旱灾害进行抗争中,也出现了由于措施不当带来的人为加大灾害的问题。因此,人必须在处理好与自然关系的框架中,认真处理好与水的关系,以保障水资源的永续利用和人类社会的可持续发展。     

Toxic effects of wastewater from various phases of monosodium glutamate production on seed germination and root elongation of crops

To make a comprehensive assessment on monosodium glutamate (MSG) wastewater pollution, a pollution exposure experiment was carried out on the seed germination and root elongation of wheat, Chinese cabbage and tomato by using the wastewater discharged from different processing phases of MSG production. The results showed that there were significantly positive linear relationships between the inhibitory rates of wheat seed germination and root elongation and the COD_cr of the mother liquor scraps. The toxicity of MSG wastewater to the test crops was in the order of tomato > Chinese cabbage > wheat, indicating that tomato was the most sensitive to the wastewater, and could be considered as an ideal toxic bioindicator. The half-effect concentrations (IC₅₀) based on the seed germination and root elongation of the test crops exposed to the wastewater discharged from various processing phases of MSG production was 22.0–32 432 and 17.3–3320 mg/L, respectively. Translated from Chinese Journal of Applied Ecology, 2006, 17(7): 1286–1290 [译自: 应用生态学报]     

DNA链断裂作为醛类污染物接触标志物的研究

应用单细胞凝胶电泳技术 ,通过对小鼠脾淋巴细胞染毒试验 ,测定了甲醛、乙醛、丙稀醛单独及联合作用下对细胞DNA分子链断裂损伤。结果表明 ,3种醛均能引起DNA分子发生链断裂 ,对于乙醛和丙稀醛存在明确的剂量 -反应关系 ,3种化合物还还存在着一定的协同作用。上述结果提示醛类污染物潜在致癌性的一个可能机制以及DNA断裂作为醛类化合物接触标志物的可能性。     

昆明市自然保护区可持续发展对策探讨

昆明市7个自然保护区存在管理机构不健全、体制不顺、基础工作薄弱、经费不足和保护与开发矛盾突出等问题。应加强立法、建立条块相互协调的管理机制,建立保护区经济补偿机制,加强规划,增加投入,改善基础设施,以实现自然保护区的可持续发展。     

羌塘高原美马错自然保护区的初步评价

拟建的羌塘高原美马错自然保护区是我国青藏高原高寒草原生态系统保存最完好的地区之一,区内含有野牦牛、藏野驴、藏羚等多种珍稀野生动物,其密度之高为西藏所仅见。该地区具有极高的自然保护价值,应作为代表青藏高原高寒草原生态系统的典型地区,列为国家级自然保护区。     

锡林浩特市可持续发展规划

首次提出锡林浩特市应以可持续发展的观点规划设计，这一规划将使使锡林浩特市以可持续方式扩大与发展，并使得位于这一地区的锡林郭勒草原自然保护区受到最小的影响。文中每项设计建议都根据现在的城市规则，经济发展和锡林郭勒自然保护区的关系得来，将对锡林浩特市的未来发展建设起到重要的参考价值。     

四方山、达尔滨湖自然保护区植被及植物区系组成

本文论述了四方山、达尔滨湖自然保护区植被生态条件、植被类型、植物类群组成、生活型组成、水分生态类型及区系地理成分等调查成果。