绿洲城市自然景观空间格局与城市生态分析——以乌鲁木齐为例

由于建立在荒漠背景之上,绿洲城市生态环境比较脆弱,城市自然景观在城市生态建设中的作用尤为重要,本文以乌鲁木齐为研究对象,借用景观生态学的方法,在ERDASINMAGINE和ARCVIEW软件的支持下进行景观要素的划分,从绿地斑块组成和格局以及城市自然廊道系统方面分析乌鲁木齐市的景观空间格局的特点及生态环境现状,提出:绿洲城市生态建设中应注重绿地系统内部结构和空间布局的调整,扩大绿地景观面积,适当提高林地比重,增加绿地组成多样性;改建河流廊道,充分发挥河流廊道的生态效益。     

森林生态资源价值补偿机制的探讨

笔者在相关研究成果的基础上,对建立森林生态资源价值补偿机制所涉及到的有关问题进行了讨论,提出了价值补偿的4种途径,即自我补偿、行业补偿、社会补偿以及国家和地方补偿等;指出了森林生态资源价值补偿的具体办法和措施,这些办法和措施带有明显的过渡性质,并呈现多样化趋势;针对湖北森林生态资源价值补偿工作的现状,提出了建立补偿机制的应对策略,“局部补偿带动全面补偿”,“先易后难,分步实施”等是应对策略的核心;强调全社会广泛的参与和积极配合,是补偿机制能否顺利建立及有效运行的关键,只有调动全社会的力量,资源价值补偿的目的才能最终实现。     

利用OWA和电路模型优化黄河流域甘肃段生态安全格局

从生态系统服务视角出发优化生态安全格局,对于维护区域生态安全格局,确保经济社会稳定发展意义重大,但现有研究缺乏对多种生态系统服务之间权衡情景下生态系统状况的认知。该研究以黄河流域甘肃段为研究单元,在测度2019年食物供给、碳固定、产水量、土壤保持及生境质量5种典型生态系统服务的基础上,利用有序加权平均(Ordered Weighted Averaging,OWA)模型识别出生态系统服务权衡度最高的优先保护区作为生态源地,利用最小累积阻力模型和电路模型识别生态廊道和战略点区域,进行生态安全格局构建与优化。结果表明:黄河流域甘肃段生态源地斑块共计169个,总面积27 460.56 km2,约占研究区总面积的19.2%。5种生态系统服务之间在全流域尺度下呈现出协同关系,甘南高原、陇中、陇东黄土高原由于受地形气候和植被覆盖以及人类活动的影响,生态系统服务差异显著。利用电路模型提取得到441条生态廊道,总体呈网状分布,贯穿东西,识别出生态节点49个。提出构建"四轴、六区、多中心"的黄河流域甘肃段生态安全空间布局优化体系,形成功能化、网络化的区域生态空间优化结构。     

生态位构建理论及其应用

总结了生态位构建在自然选择压的改变、非基因继承、基因具有间接的相互作用和表型的双重角色等4个方面的理论;探讨了生态位构建在进化生物学、生态学协同进化、人类基因遗传和文化过程的关系、管理科学等相关研究领域的应用情况和发展前景.     

绥芬河珠星雅罗鱼溯河生殖群体结构特征研究

珠星雅罗鱼Leuciscus haronensis（Gunther）为鲤科鱼类中少有的溯河洄游类型。本研究采集了880尾2009年度绥芬河溯河洄游生殖群体样本,分析了溯河期、产卵期以及个体的体长、体重组成、年龄与生长、生殖能力、成熟系数、肥满度等主要生态学特征及种群数量。绥芬河珠星雅罗鱼生殖群体分三批溯河繁殖,即3月中...     

Using knowledge of behaviour and optic physiology to improve fish passage through culverts

Culverts reduce connectivity for aquatic animals by being both a hydraulic and physical barrier. However, altered light intensity may also be a behavioural barrier to fish movement, especially for diurnal species that have adapted to moving when it is light. We propose that knowledge of optical physiology and fish behaviour, two important mechanisms underpinning movement, can inform efforts to improve fish movement through culverts. We firstly review the sensory systems of fish with reference to visual sense and explore how this affects fish movement. We then highlight theoretical knowledge that can help us understand fish behaviour and the potential mismatch between the conditions under which fish have evolved and altered conditions within culverts. We describe potential knowledge gaps and directions for future research to improve our understanding of how culverts may affect fish movement. Finally, we explore the potential costs and ecological benefits of different mitigation options to identify those with the most promise for managing the light environment in culverts to facilitate movement. For researchers and managers exploring this subject, we suggest an approach that: (a) identifies light requirements for movement by different species, (b) tests movement under different light conditions and (c) considers an integrative assessment method for testing fish behaviour around culverts. Understanding how optical physiology, fish behaviour and culvert design influence fish movement can improve connectivity for a range of species.     

Using fishers' anecdotes, naturalists' observations and grey literature to reassess marine species at risk: the case of the Gulf grouper in the Gulf of California, Mexico

Designing fishing policies without knowledge of past levels of target species abundance is a dangerous omission for fisheries management. However, as fisheries monitoring started long after exploitation of many species began, this is a difficult issue to address. Here we show how the ‘shifting baseline’ syndrome can affect the stock assessment of a vulnerable species by masking real population trends and thereby put marine animals at serious risk. Current fishery data suggest that landings of the large Gulf grouper (Mycteroperca jordani, Serranidae) are increasing in the Gulf of California. However, reviews of historical evidence, naturalists’ observations and a systematic documentation of fishers’ perceptions of trends in the abundance of this species indicate that it has dramatically declined. The heyday for the Gulf grouper fishery occurred prior to the 1970s, after which abundance dropped rapidly, probably falling to a few percent of former numbers. This decline happened long before fishery statistics were formally developed. We use the case of the Gulf grouper to illustrate how other vulnerable tropical and semi‐tropical fish and shellfish species around the world may be facing the same fate as the Gulf grouper. In accordance with other recent studies, we recommend using historical tools as part of a broad data‐gathering approach to assess the conservation status of marine species that are vulnerable to over‐exploitation.     

鸭绿江花羔红点鲑研究进展

本文综述了鸭绿江花羔红点鲑在形态,生态和养殖等方面研究进展,并提出今后的主要研究方向,保护措施和发展前景。     

The effect of different HUFA enrichment emulsions on the nutritional value of rotifers (Brachionus plicatilis) fed to larval haddock (Melanogrammus aeglefinus).

A feeding study was conducted in the winter 2001 to determine the effects of feeding rotifers (Brachionus plicatilis) enriched with various levels of essential fatty acids on the growth and survival of haddock larvae (Melanogrammus aeglefinus). Rotifer enrichment treatments were: 1) mixed algae, 2) high DHA (docosahexaenoic acid, 22:6n-3), 3) high DHA and EPA (eicosapentaenoic acid, 20:5n-3), and 4) DHA, EPA, and AA (arachidonic acid, 20:4n-6). Larvae were fed rotifers enriched with the different treatments from days 1 to 16 post-hatch. From day 17 until 25 all treatment groups were fed rotifers reared on mixed algae and then weaned onto the International Council for Exploration of the SEA (ICES) Standard Reference Weaning diet (http://allserv.rug.ac.t/aquaculture/rend/rend.htm) over a five day period. The experiment was terminated on day 41 post-hatch. The enrichment treatments affected the fatty acid composition of the rotifers and correlated with the accumulation of these fatty acids in the haddock larvae. However, no significant differences in larval growth or survival to 40 days post hatch were detected, suggesting that all treatments provided the minimal essential fatty acid requirements for haddock.     

Compensatory growth in Atlantic halibut: Effect of starvation and subsequent feeding on growth, maturation, feed utilization and flesh quality

A group of juvenile Atlantic halibut (mean, SD, 199.5 g, 44.7) was split into two experimental groups: one group was fed in excess twice a day and later five days a week (i.e. Control group), and the other group was starved for 5 weeks and then subsequently re-fed for 10 weeks (i.e. 5/10 starvation/re-fed group). This treatment was repeated for three years until the fish were harvested (mean final weight, 4.4 kg). A size +specific compensatory response was seen; partial compensation was observed in halibut weighing less than 500 g whereas full recovery growth was seen in halibut over 2 kg. Food consumption and feed conversion efficiency was measured during two full 5/10 starvation/re-fed cycles. The Control group consumed 86% more food in the measurement period, whereas the FCE 40% higher in the 5/10 starvation/re-fed group (FCE = 0.95) compared to the Control group (FCE = 0.68). In males lower gonadosomatic index (2.2 vs. 3.0) and plasma 11-ketotestosterone (0.22 vs. 1.26 ng ml^− 1) levels in the 5/10 starvation/re-fed group were observed during late winter and spring of 2006 (age 3 years) indicating higher age at 1st maturity. Starvation had a significant effect for improving the quality as starved fish had higher muscle pH (6.4 vs. 6.2), less gaping (0.1 vs. 0.3) and harder texture (61.4 vs. 57.6 N). Overall, the rearing on a repeated 5/10 starvation/re-fed regime for 3 years led to full growth compensation, higher feed conversion efficiency, lower male maturation and improved flesh quality.