城市、绿化与人居环境的可持续发展策略

根据大量资料统计说明：成都市随着经济发展,环境有恶化趋势,人口的迅速增加,建筑面积的扩大,导致人均公共绿化面积减少。从６０年代开始,市区雾日增多、日照百分率降低、连阴雨次数、洪涝发生次数逐渐增多,而且火灾发生次数逐年增多,市区重于效区。城市环境必须保持经济、社会与生态环境协调发展。     

Artemia parthenogenetica in Lake Hayward, Western Australia. I. Interrupted recruitment into adult stages in response to seasonal limnology

Lake Hayward, Western Australia, is a pristine, monomictic coastal lake with a residual brine (depth=1.5 m) of 200 gL⁻¹: stratification in winter (May to October) followed the input of ground water and rain. The epilimnion had temperature ranges of 10–30°C, and salinity from 65–110 g L⁻¹. Maximum depth in winter was 2.4 m. The population structure of the brine shrimpArtemia parthenogenetica, the dominant metazoan grazer in Lake Hayward, was studied from September, 1989, to February, 1991. The L. Hayward population ofA. parthenogenetica is predominantly ovoviviparous with little recruitment into the adult population. Cyst production occurs in summer, and there was evidence for recruitment from cyst hatching in the winters of 1989 and 1990. Nauplii were continuously present throughout the study period. Nevertheless, recruitment through to adult stages as defined by the presence of gravid females occurred only twice: in October–December, 1989 and in December, 1990. Based on limited observations of long-term survival of laboratory cultures, we believe that the major mechanism controlling nauplius survival and recruitment ofArtemia in Lake Hayward is food quality and quantity.     

Potential Effects of Global Warming on Waterfowl Populations Breeding in the Northern Great Plains

The Prairie Pothole Region (PPR) of the Northern Great Plains is the most important breeding area for waterfowl in North America. Historically, the size of breeding duck populations in the PPR has been highly correlated with spring wetland conditions. We show that one indicator of climate conditions, the Palmer Drought Severity Index (PDSI), is strongly correlated with annual counts (from 1955 to 1996) of both May ponds (R2 = 0.72, p < 0.0001) and breeding duck populations (R2 = 0.69, p < 0.0001) in the Northcentral U.S., suggesting the utility of PDSI as an index for climatic factors important to wetlands and ducks. We then use this relationship to project future pond and duck numbers based on PDSI values generated from sensitivity analyses and two general circulation model (GCM) scenarios. We investigate the sensitivity of PDSI to fixed changes in temperature of 0°C, +1.5°C, +2.5°C, and +4.0°C in combination with fixed changes in precipitation of -10%, +0%, +7%, and +15%, changes spanning the range of typically-projected values for this region from human-induced climatic change. Most (11 of 12) increased temperature scenarios tested result in increased drought (due to greater evapotranspiration under warmer temperatures) and declining numbers of both wetlands and ducks. Assuming a doubling of CO2 by 2060, both the equilibrium and transient GCM scenarios we use suggest a major increase in drought conditions. Under these scenarios, Northcentral U.S. breeding duck populations would fluctuate around means of 2.1 or 2.7 million ducks based on the two GCMs, respectively, instead of the present long-term mean of 5.0 million. May pond numbers would fluctuate around means of 0.6 or 0.8 million ponds instead of the present mean of 1.3 million. The results suggest that the ecologically and economically important PPR could be significantly damaged by climate changes typically projected. We make several recommendations for policy and research to help mitigate potential effects.     

四川大麦地泥盆纪煤的物质组成与早期陆生植物生态的关系

大麦地一带中泥盆统产有数据透镜状煤层,其中角质体含量一般〉７５％,而且不同富煤点煤中角质体类型,含量,结构特点都不相同,存在明显的分异现象。这种分异现象反映出早期陆生植物对环境的适应和生态特点,是聚煤环境,植物类型和生态等因素综合作用的结果。     

黄河流域水域生态系统服务与经济发展时空协调性

黄河流域对维护中国生态安全、促进社会经济发展具有重要的战略地位。基于2000、2005、2010、2015、2020年5期遥感解译数据和经济社会统计数据,测算了黄河流域9省71个市（州、盟）的水域生态系统服务价值,并通过构建生态系统服务与经济发展一致性指数对二者时空协调性进行分析。结果表明：（1）研究时段内,黄河流域水域面积逐年增加,其中上游地区增长最多、增幅较小,下游地区增长较多、增幅最大,中游地区有小幅度减少。从水域类型变化来看,水库坑塘增加最多、变化幅度最剧烈,滩地和滩涂面积缩小、变化较为平缓。（2）研究时段内,黄河流域水域生态系统服务价值逐年上升,但增幅逐渐趋缓,下游地区水域生态系统服务价值增幅最大、上游次之、中游最低,其中2015—2020年陕西省、山西省以及整个中游河段甚至出现了下降的情况。（3）总体上看,黄河流域水域生态系统服务与经济发展在研究时段内呈现出不协调状态,并以经济集聚高于生态系统服务集聚为主,并且长期保持不变,但这种不协调性在空间上出现分异,上游地区以生态系统服务集聚高于经济集聚类型为主,中、下游地区以及各省会城市以经济集聚高于生态系统服务集聚类型为主。     

西方城市政治生态学研究进展与理论探讨

政治生态学是西方人文政治地理研究人与自然/环境互动的辩证关系的核心领域。城市政治生态学作为政治生态学的衍生分支同样经历了二十年快速的发展,这一领域尚未获得中国人文地理学界的系统关注。本文对西方文献中城市政治生态学的理论发展、研究议题以及近期前沿的学术争论和理论拓展进行了系统梳理与探讨。政治生态学分析方法批判和克服了技术专家治国论、新马尔萨斯主义、增长的极限等非政治视角的环境生态解释。理论溯源于新马克思主义城市地理学的城市政治生态学,继承了政治生态学的政治视角,但同时对政治生态学和城市研究两个领域中的自然/社会的二元对立提出了批判,以社会-生态混合体为理论出发点,打破并超越了城市-自然的对立和二元划分,通过研究自然的生产、循环与新陈代谢,将城市概念化为动态变化的社会-生态混合体,并揭露了城市环境的生产和社会-生态演化过程本质上是一个政治过程,突出强调了社会-生态混合体演化变迁过程的政治经济学、政治过程、权力关系的分析对于理解不平等的城市环境的核心作用。近5年来,城市政治生态学研究在后结构主义理论启发下扩展了经典马克思主义城市政治生态学,拓展了理论溯源,丰富了对城市环境和生态的解释,并产生了一系列围绕方法论上的城市主义、星球城市化、多地点方法论等的前沿学术批判与争论。     

环境脆弱性研究述评

综述了生态(环境)、自然灾害、地下水、水资源等领域的脆弱性研究现状，指出环境脆弱性研究领域可以归为人文系统的脆弱性与自然系统的脆弱性两类；就脆弱性研究的复杂性，可以分为相对较为复杂的生态脆弱性与水资源脆弱性研究及相对较为单一的地下水脆弱性与灾害脆弱性研究；就某个具体领域的脆弱性研究应包括其本质脆弱性及特殊脆弱性研究。另外在研究方法上主要是采用定性与定量相结合的方法，同时对于环境脆弱性的防范与适应对策也是极为重要的研究内容。     

从气候的角度看大同市生态畜牧经济区建设

雁门关区域地处农牧交错带，植被稀疏，水土流失严重，生态环境恶劣，农业生产结构单一，农民收入低而不稳。2001年，省委、省政府经过科学论证，高瞻远瞩，审时度势，提出了在雁门关区域28个县建设雁门关生态畜牧经济区。大同市9县区地处雁门关腹地，建设生态畜牧经济区，责任重大，意义深远。本文从大同市气候的角度出发，提出建设雁门关生态畜牧经济区的思路和对策，旨在推动雁门关生态畜牧经济区建设。     

Some information on testate amoebae of Iceland

In samples of mosses collected during an expedition in the year 1987 along the southern border of Iceland, in seven habitats on the slopes of Skerhöll Hill, south of the glacier Svínafellsjökull, 80 taxa of testate amoebae have been recorded. From these taxa 24 species are new to Iceland. Up to now, including our own data, on the basis of available sources 174 taxa have been reported for Iceland. In the mosses Racomitrium heterostichum and Racomitrium fasciculare an Assulina muscorum — Centropyxis globulosa-association has been recorded.     

干旱地区内陆河流域水文问题的研究实践与展望

过去，干旱地区内陆河流域水文研究主要偏重于山区水文，注重山区来水及径流分析，而很少涉及灌区问题和生态问题，对绿洲水文和荒漠水文的研究十分缺乏。以新疆为例，通过对干旱地区河流的基本特征和水文机理的分析研究，从径流形成、水资源开发利用、生态环境保护三位一体，即从全流域水文循环的角度出发，提出了以山区水文、绿洲水文、荒漠生态水文为三大构成要素的干旱地区内陆河流域水文系统的新概念，并基于干旱地区内陆河流域水文问题的研究实践，提出了各自领域的研究内容和方向，进一步拓宽了水文问题的研究领域，对水文学科的研究与发展提出了新的思路，注入了新的内容。