Identifying a suite of surrogate freshwaterscape fish species: a case study of conservation prioritization in Ontario's Far North,Canada

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城镇-农业-生态协调的高原湖泊流域土地利用优化

为了解高原湖泊流域土地利用布局现状,探究在"城镇-农业-生态"协调下的高原湖泊流域土地利用空间优化配置方案,该文以抚仙湖流域为例,基于3S技术,运用MCR-CLUE-S模型,研究流域城镇建设情景、农业开发情景、生态保护情景和综合优化情景4种模式下2030年国土空间的结构和布局,最终提出抚仙湖流域"城镇-农业-生态空间"协调下的土地利用空间优化分区。结果表明:1)2005、2010和2015年抚仙湖流域城镇空间呈上升趋势,农业空间呈下降趋势,生态空间先升后降,10 a间空间分布格局基本一致;2)以重要水源地、湖滨湿地和大面积自然林地为保护源,选取高程和坡度等8个阻力因子,采用最小累积阻力模型和累积耗费距离模型构建抚仙湖流域生态安全格局,以及有利于生态保护的"源"核心区、生态保护区、生态边缘区、农业开发区、农业边缘区和城镇建设区;3)以生态功能分区面积为约束条件,通过Markov模型结合CLUE-S模型模拟抚仙湖流域2030年城镇建设、农业开发和生态保护情景下"城镇-农业-生态空间"的优化布局。城镇建设情景综合考虑生活需要以及政策指导下以开发城镇空间为主导的"城镇-农业-生态空间"数量及空间结构的发展方向;农业开发情景控制城镇空间规模,开发部分生态空间潜力;生态保护情景下农业空间面积有所减少,城镇空间面积少量增加;4)抚仙湖流域2030年综合优化情景模式下,根据土地功能的不同,划为城镇空间、农业空间、生态空间、城镇-农业空间、城镇-生态空间、农业-生态空间和城镇-农业-生态空间,其中农业-生态空间最小,生态空间最大;5)通过分析4种情景下区域发展的特点,结合抚仙湖流域耕地保护、生态保护和经济社会发展等多种因素,认为综合情景方案更合理并更适合当地的发展,其他3种单要素情景方案可为综合情景方案的实施进行相关的补充和调整。研究结果可为抚仙湖流域国土空间规划和生态保护战略决策提供参考依据。     

中国内陆盐湖卤虫资源开发利用的研究

我国内陆盐湖卤虫资源分布地区约有４３处，其中重点产区有内蒙古的额吉淖尔、黄旗海；青海的尕海、小柴旦湖；新疆的艾比湖、巴里坤湖；山西的解池等７处。卤虫资源量为２５０００～３００００ｔ／ａ；卤虫卵５００～７００ｔ／ａ；可开发量：鲜卤虫１５００ｔ／ａ，原料卤虫卵２００～３００ｔ／ａ。研究了主要盐湖卤虫生物学特性和投喂对虾幼体的饵料效果以及卤虫的孵化特性和加工工艺。并对我国内陆盐湖卤虫资源进行了评估，提出了繁殖保护和开发利用的意见。     

The effects of winter ice cover on the trophic ecology of whitefish (Coregonus lavaretus L.) in subarctic lakes

Lakes in Arctic and subarctic regions display extreme levels of seasonal variation in light, temperature and ice cover. Comparatively little is known regarding the effects of such seasonal variation on the diet and resource use of fish species inhabiting these systems. Variation in the diet of European whitefish Coregonus lavaretus (L.) during periods of ice cover in this region is often regarded as ‘common knowledge’; however, this aspect of the species' ecology has not been examined empirically. Here, we outline the differences in invertebrate community structure, fish activity, and resource use of monomorphic whitefish populations between summer (August–September) and winter (February–March) in three subarctic lakes in Finnish Lapland. Benthic macroinvertebrate densities did not exhibit measurable differences between summer and winter. Zooplankton diversity and abundance, and activity levels of all fish species (measured as catch per unit effort) were lower in winter. The summer diet of C. lavaretus was typical of a generalist utilising a variety of prey sources. In winter, its dietary niche was significantly reduced, and the diet was dominated by chironomid larvae in all study sites. Pelagic productivity decreases during winter, and fish species inhabiting these systems are therefore restricted to feeding on benthic prey. Sampling time has strong effect on our understanding of resource utilisation by whitefish in subarctic lakes and should be taken into account in future studies of these systems.     

The use of littoral mesohabitats and their macroinvertebrate assemblages in the ecological assessment of lakes

• 1. Historically, ecological assessment of lakes has depended on open‐water chemical and phytoplankton analysis, with trophic status determined by chlorophyll a and total phosphorus following the general protocol of the OECD lake classification scheme. This has been accompanied by a prevailing opinion that the littoral zone of lakes is too heterogeneous to allow meaningful inter‐lake comparisons.
• 2. Council of the European Communities Directive 2000/60/EC establishing a framework in the field of water policy (the Water Framework Directive) requires a broader approach to ecological assessment, including the need to incorporate a range of biotic variables. This paper describes the results of a monitoring programme designed to determine within‐ and among‐lake variation of macroinvertebrate communities found in defined mesohabitats of 22 lakes incorporating a range of lake types. Three sampling approaches were applied to the study.
• 3. Triplicate macroinvertebrate samples from a cobble/pebble mesohabitat of 11 lakes showed that community composition from a standard habitat was robust.
• 4. Twinned samples from contrasting habitats of pebble/cobble and macrophyte dominated mesohabitats of 21 lakes had greater similarity within than among lakes. This showed that even across contrasting habitat structure, macroinvertebrate assemblages can provide a reliable lake‐specific indicator.
• 5. Multivariate analysis of replicate samples from 15 visually distinct mesohabitats in one lake showed that within‐lake variation could, nevertheless, be identified as distinct clusters of invertebrate assemblages.
• 6. Conclusions from the work are that variations within lakes were nested in among‐lake variation across a range of lake types, and that macroinvertebrate assemblages can provide meaningful assessment of ecological differences across lakes. Monitoring can, however, produce a substantial amount of ‘noise’ from the data that reflects the complexity of macroinvertebrate community structure in littoral zones. It is recommended that incorporation of macroinvertebrates in ecological assessment is most useful when confined to well defined mesohabitats rather than attempt to incorporate a complete range of mesohabitats within a single lake.

Copyright © 2003 John Wiley & Sons, Ltd.     

武汉城市湖泊水质及水体富营养化现状评价

为了判别武汉市典型城市湖泊汤逊湖、野芷湖、黄家湖和东野芷湖的水质状况,从2011年3月～2012年2月,对这四个湖泊进行了周年水质监测。采用了水体总氮、总磷、叶绿素a、透明度等参数,对水质现状、水体富营养化程度进行了综合分析。结果表明,该四湖的水质污染程度呈现明显的梯度。水体富营养化综合加权指数法评价表明,湖泊全年富营养化状态级别处于中营养到轻度富营养化之间。     

干旱区平原湖泊旅游资源可持续开发研究——以新疆艾丁湖为例

干旱区的平原湖泊,不仅是该区域重要的水资源,而且是举足轻重的环境资源,它的"冷岛效应"比绿洲更强,这对于西北干旱区的社会、经济、环境可持续发展至关重要.但干旱区平原湖泊的生态环境非常脆弱,人为扰动对其影响较大.随着近年来干旱区平原湖泊旅游资源开发的增多,如何保证这些旅游资源的可持续发展,尽可能保护这些生态环境脆弱地区可...     

Effects of stocked trout on native fish communities in boreal foothills lakes

Nasmith LE, Tonn WM, Paszkowski CA, Scrimgeour GJ. Effects of stocked trout on native fish communities in boreal foothills lakes.
Ecology of Freshwater Fish 2010: 19: 279–289. © 2010 John Wiley & Sons A/S Abstract – Ecological effects of stocking nonnative trout into lakes are receiving increased attention, especially in alpine environments. We assessed effects of stocked trout on native forage fishes in the boreal foothills of Alberta (Canada) by comparing fish density, population size structure and spatial and temporal activities in stocked and unstocked lakes over 3 years (2005–2007). The numerically dominant dace (primarily Phoxinus spp.) were larger in stocked lakes, consistent with size‐limited predation. Dace were also more crepuscular and concentrated on the lake‐bottom in stocked lakes, compared to more daytime activity in the water column in unstocked lakes. There were, however, no demonstrable effects of trout on the abundance of forage fish. The lack of major population‐level impacts of stocked trout suggests that current stocking practices, characteristics of boreal foothill lakes (e.g. thermal structure, abundant invertebrates, dense macrophytes) and/or behavioural adjustments of forage fish contribute to healthy native fish populations in our stocked lakes.     

乌梁素海和岱海的水-沉积物系统中有机磷分布特征

以乌梁素海和岱海2个不同类型湖泊为研究对象,系统探讨了2个湖泊上覆水和沉积物中有机磷（Or-P）的地球化学特征。结果表明,乌梁素海和岱海上覆水中溶解性有机磷（DOP）的含量范围分别为0.02～0.12mg·L^-1和0.01～0.03mg·L^-1,2个湖泊上覆水中DOP均占TDP的60%以上,是上覆水中TDP的重要组成部分和主要存在形态;乌梁素海和岱海沉积物中有机磷（Or-P）的平均含量分别为19.25～69.40mg·kg^-1和168.21～178.41mg·kg^-1;2个湖泊上覆水中DOP含量明显高于英格兰Tamar河口区,2个湖泊沉积物中Or-P的含量低于长江中下游浅水湖泊。据估算,乌梁素海和岱海上覆水中的DOP库分别达到12t和10t;这2个湖泊沉积物中Or-P的差异性反映了湖泊环境及生态类型对Or-P生物有效性的重要影响,揭示有机磷库是不容忽视的潜在生物有效磷源。     

基于底栖动物生物完整性的武汉市湖泊生态系统健康评价

大型底栖动物是生态系统健康评价最常用的生物类群。本文以武汉市浅水湖泊为研究区域,分析近20年（1998-2018）野外调查的104个湖次底栖动物数据,初步构建适合我国中部浅水湖泊底栖动物完整性评价的多参数指数MMI (Multimetric Index),包括36个群落结构性参数和35个功能性参数共71个生物参数,经筛选武汉湖泊MMI指数由总分类单元数、腹足类个体数%、功能趋异指数和穴居者%共4个核心指标组成。通过比值法将健康状态划分为5个等级：健康、亚健康、一般、差和极差。回归分析结果表明,MMI指数不仅与富营养化指标关系显著,能够反映湖泊营养状态的变化;而且能够显著区分城市湖泊与农村湖泊,城市湖泊的健康状况明显差于农村湖泊。基于MMI的健康评价结果表明,武汉市湖泊健康状况一般,其中34.6%湖泊健康状况亚健康以上,41.3%的湖泊健康状况处于一般水平,24.1%湖泊健康状况较差。本研究构建的包含功能性状参数的MMI完整性指数,可在湖泊健康评价中推广应用,也为湖泊修复和可持续发展提供了科学基础。