西藏高山草原土放线菌研究初探

本文采用常规方法研究西藏6个分布于海拔4,240～4,850m 的高山草原土的放线菌数量,对从6个土样中分离纯化所得的454株放线菌中选出具有代表性的84株菌进行分离鉴定。结果表明:西藏同一土类不同土样中放线菌数量差异很大;84株代表性菌可分为9个属,链霉菌属(76.2%)占优势。     

论草原生态系统中微气候研究的重要作用

草原生态系统中微气候的研究工作开始于六七十年代，主要是应用微气候学和生态学研究草原生态系统中微气候的变化规律及其与动植物的关系。这些研究工作不但丰富了生态学理论，而且对草地生产有重要的指导意义。中国在这方面的研究起步晚，报道甚少。文章旨在论述微气候学研究在草原生态系统中的重要地位，推动中国在这一领域的发展。     

新疆喀依纳尔——青(羊居)(羊吕)山荒漠草原地带啮齿动物调查

本文报道了新疆喀依纳尔——青(羊居)(羊吕)山荒漠草原地带啮齿动物的的种属组成、啮齿动物群落与栖息生境的关系、繁殖情况以及动物地理分布的资料。     

Lotka—Volterra系统对部分变元的全局稳定性

本文对Lotka—volterra生态数学模型的稳定性进行了讨论,引入关于部分变元稳定性的概念并给出判断其稳定性的一个充分条件。     

Microbial methylation of benzenethiols and release of methylthiobenzenes

Summary Three phylogenetically diverse microorganisms methylated several different chloro- and nitro-substituted benzenethiols to yield the corresponding methylthiobenzenes. These products were identified by gas chromatography-mass spectrometry. In several cases large percentages of the methylthio products were released by intact cells into the medium, suggesting that microbial methylation of xenobiotic thiols may be a significant biotransformation in many ecosystems.Acknowledgments. This investigation was supported by research grant ES 02639 from the National Institute for Environmental Health Sciences, and an equipment grant (RR07013) from the Biomedical Research Support grant program. Division of Research Resource, NIH. We thank Steve Hawthorne for assistance in performing GC-MS analyses.     

沙尘天气对内蒙古草原城市大气环境质量的影响研究

沙尘不仅是生态环境恶化的重要标志,也会污染大气环境,影响气象、气候和人体健康。为了探讨沙尘天气对内蒙古草原城市大气环境的影响,综合利用遥感影像与地面观测数据,研究了沙尘天气对锡林郭勒盟草原城市大气环境质量的影响,以期为沙尘天气环境影响评价提供理论依据。研究表明利用MODIS(the moderate resolution imaging spectroradiometer)数据可以实现沙尘活动的遥感监测,结果与基于地面观测发生规律一致;并得到气溶胶自动观测网(aerosol robotic network,AERONET)AOD(aerosol optical depth)产品验证。沙尘天气引起草原城市能见度下降,空气环境质量下降。大气污染主要由颗粒物的增加引起;但伴随沙尘天气的大风使CO、NO_2、SO_2等污染物浓度下降,具有清除人为源所排放污染物作用。     

Methane emissions from wetlands on the Qinghai-Tibet Plateau

The areal extent of cold freshwater wetlands on the Qinghai-Tibet Plateau (QTP) is estimated at 0.133 × 10⁶ km², suggesting a significant methane potential. Methane fluxes from wet alpine meadows, peatlands,Hippuris vulgaris mires and secondary marshes were 43.18, 12.96, −0.28 and 45.90 mg · m⁻² · d⁻¹, respectively based on the transect flux studies at the Huashixia Permafrost Station (HPS) from July to August 1996. Average CH₄ fluxes in the thaw season were extrapolated at 5.68 g · m⁻² according to the areal percentage of wetland areas in the Huashixia region. The CH₄ fluxes at four fixed sites, representative of similar ecosystems, ranged from −19.384–347.15 mg · m⁻² · d⁻¹, and the average CH₄ fluxes varied from 6.54 to 71.97 mg · m⁻² · d⁻¹ at each site during the observation period from April to September 1997. The CH₄ emissions at each site during the entire thaw season was estimated from 1.21 to 10.65 g · m⁻², displaying strong spatial variations. Seasonal variations of CH₄ fluxes also were observed at four sites: CH₄ outbursts occurred upon the spring thaw in May and June, CH₄ fluxes increased afterwards with rising soil temperatures. Episodic fluxes were observed in summer, which influenced the average CH₄ fluxes considerably. Annual CH₄ emissions from cold wetlands on the QTP were estimated at about 0.7–0.9 Tg based on the distribution of wetlands, representative CH₄ fluxes, and number of thaw days. The centers of CH₄ releasing were located in the sources of the Yangtze and Yellow rivers, and Zoigê Peatlands.     

西宁市城市灾害与绿地减灾效应

依据城市化观测资料和研究文献,分析了西宁市城市化现状城市灾害,并从防灾减灾角度提出了绿地在城市减灾中的作用     

关于城市交通、物流、生态综合发展的复杂系统研究方法

必须综合考虑城市交通、物流和生态等城市化问题；这类问题不存在“一劳永逸”的解决方案；这类问题不存在一般意义的最优解，更不存在唯一的最优解。因此，基于复杂系统的思想，讨论在“不断探索和改善”的原则下，如何利用人工系统、计算实验、平行系统等新方法和理论，结合从定性到定量的综合集成方法和并行分布式高性能计算技术。寻求城市交通、物流和生态等城市化问题的有效解决方案，建立城市交通系统全面、协调、可持续发展的新型研究体系和方法。