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1.
罗武松  金津  王金秋 《水产科技情报》2016,43(3):151-154, 159
阐述了在人工控制的模拟自然生境条件下淞江鲈鱼种的两种产业化培育模式:车间系统产业化培育和车间—池塘接力产业化培育。前者包括模拟自然生境浅海海水生态系统、河口混盐生态系统和河流淡水生态系统的车间系统调控技术,鱼种早期培育、淡化技术和关键生态因子的调控技术等;后者即在鱼种培育的前期,水环境要求海水和半咸水时,在模拟自然生境的车间系统中进行培育,鱼种淡化结束后移至池塘环境中继续培育,该模式的技术要点包括车间培育阶段的鱼种淡化、鱼种驯化,池塘培育阶段的池塘准备、饵料生物培养、鱼种放养、水质调控和鱼种捕捞。  相似文献   

2.
新疆塔里木河水系土著鱼类区系组成与分布   总被引:11,自引:0,他引:11  
2003年-2007年对新疆塔里木河水系土著鱼类的种类和分布进行了一次全面调查,根据不同的海拔和生境,在整个调查范围内设置鱼类采集点200个,共采集鱼类标本3000余号,经鉴定有1目2科5属12种,均为中亚高山复合体的裂腹鱼和高原鳅种类。其中国家Ⅰ类保护动物扁吻鱼仅分布在海拔1 500 m以下,裂腹鱼属鱼类主要聚居于海拔1 300~2 700 m一带,裸重唇鱼属鱼类主要聚居于海拔1 500~2 900 m一带,重唇鱼属鱼类主要聚居于海拔2 700~3 700 m一带。高原鳅分布在裂腹鱼分布范围之内,最高可至3 700 m,土著鱼类的水平及垂直分布差异明显,水平分布表现出明显的多样性和地域性,垂直分布具有明显的地带性。塔里木河水系土著鱼类在大尺度、大空间的分布格局有缩小的趋势,扁吻鱼栖息地岛屿化程度高。  相似文献   

3.
开展面向湖泊健康的生态需水研究,构建有效的湖泊生态需水调控和保障体系,对于水资源科学管理、水生态系统修复、湖泊健康保护、水生态文明构建等具有重要意义。选取洪泽湖为研究对象,针对多闸坝条件下的湖泊生态需水问题,进行了系统的研究。研究表明,通过调控上游入湖水系主要控制工程以改变洪泽湖过境水过程,可显著提升洪泽湖生态水位保障效果,在此基础上增加引调水量6.86亿m3/年可保障每年水位过程均满足生态水位过程要求,年保证率达100%,生态水位偏离差为0m。  相似文献   

4.
熊文  邱凉 《水利渔业》2006,26(2):63-66
景观格局规划以城市景观生态多样性保护和异质性维持为基础,通过景观生态恢复和重建,构建城市景观生态安全格局,以实现城市生态持续发展。城市景观生态安全格局包括一些关键性的局部、点及位置关系,对维护和控制某种生态过程有着关键作用,对城市的社会、生态、经济持续、健康发展具有重要意义。通过分析广州城市生态适应性,确定生态保护源地,分析了各个保护源的景观阻力面,最后根据景观生态原理确定广州市城市景观生态安全格局中的“缓冲带”、“廊道”、“战略点”、“隔离带”,构建了广州市城乡一体化景观生态安全格局。  相似文献   

5.
海洋牧场与休闲渔业融合发展是我国海洋牧场发展方向之一,现阶段海洋牧场休闲产业规模较小,类型较为单一,主要以游钓和潜水休闲为主,其景观观赏性功能有待深入挖掘和开发。海洋牧场景观格局研究主要针对海洋牧场景观资源的形成、分布及其在景观空间上排列和布局等方面,发现并了解其生态系统或空间属性变异程度表观现象。本研究以粤东柘林湾海洋牧场示范区为案例,采用景观格局分析法对景观要素特征指数及景观异质性指数进行计算,研究表明,粤东柘林湾海洋牧场示范区自然景观为景观基质,半自然景观斑块面积最多,故破碎度指数最高,受人类活动影响最大,对生物多样性保护及景观生境维护应加强;文化景观与整体景观分离度较大,导致整体景观连通性较差,影响景观效果;滨海景观斑块较少,丰富度不高,但根据调查显示周边旅游资源丰富,因此缺乏与粤东柘林湾海洋牧场结合开发利用。总之,本研究通过解析海洋牧场景观格局空间内不同景观的分布状况及相互之间的作用和影响,为下一步进行景观生态规划提供数据支持,并为开发和利用海洋牧场休闲渔业与生态景观可持续化发展,综合提升海洋牧场的生态、经济和社会价值提供支撑。  相似文献   

6.
“三湖”流域独特的地理以及资源优势使其成为玉溪市社会经济发展的重要基础。以“三湖”流域为例,基于景观格局指数建立生态风险模型并利用空间自相关分析、地统计学分析、重心转移等方法对研究区内景观格局变化特征以及生态风险演变进行探究。结果表明:(1)由于社会发展以及人类活动导致建筑用地的分离度等在研究期内呈线性减少趋势,而草地的破碎度在20年将呈上升趋势,由2000年的0.55增长到2020年的0.93。(2)生态风险格局在空间上呈现显著正相关,Moran’s I指数由2000年的0.522下降至2022年的0.513,表明研究区内景观生态风险值在空间分布上的依赖性减弱,空间趋同性逐渐降低。(3)研究区内多年间生态风险呈现先上升后下降的趋势且生态风险格局重心整体向西南偏移,高风险区主要分布在研究区北部的林草地带以及湖泊周围,20年来面积增加了6212.07公顷。研究结果为流域内资源的开发、生态安全保护等重大决策提供支持和帮助。  相似文献   

7.
河流生境健康的准确评估可以为河流生态系统的保护与修复提供重要依据。以长江流域典型支流雅砻江、赤水河、乌江以及汉江为研究对象,对各支流的生境状况进行调查评估,探索影响不同支流生境状况的主要因子,从而为长江流域河流生境保护和修复提供支撑。从河流物理生境形态、河流岸边带生境和水环境特征3个方面选取了10个指标,构建河流生境评价的指标体系。基于该评价体系,2017年8-9月对4条支流的162个断面进行了调查并对河流生境进行了综合评估。评价结果表明,雅砻江、赤水河、乌江、汉江的河流生境综合指数(RHI)分别为124.7、158.5、137.8、135.5,其中赤水河评价等级为“优”,其他河流评价等级均为“良”。人类活动、河岸植被覆盖、河道蜿蜒度等是影响各支流生境变化的主要驱动因子。建议强化支流国土空间管控,建立自然保护区,对具有重要生态服务功能的支流河段开展生态修复。  相似文献   

8.
水生态监测是水生态健康评估、保护及修复的重要基础。随着我国经济转向高质量发展和生态文明建设的不断推进,水生态监测逐步规范化和系统化。本文梳理了国内外水生态监测与评价的发展历程,总结了欧盟和美国水生态监测及评价体系构建的成功经验及对我国的借鉴意义,进一步分析了长江流域水生态监测工作现状及存在的问题,并以问题为导向,从流域统一监管、监测站网优化、监测工作常态化、监测标准体系完善、监测能力提升等多个层面提出建议,以期为长江流域和我国水生态监测和评价工作提供参考。  相似文献   

9.
作为一种重要的时空分析方法,空间信息技术在渔业资源及生态环境监测与评价中极富优势,并能在未来加强渔业的可持续管理水平。本文总结了目前空间信息技术(包括地理信息系统、遥感、空间模型、空间统计学)在渔业资源及生态环境监测与评价中的应用及研究进展,主要集中在四个方面:(1)在渔业生态环境数据采集和监测中的应用;(2)在渔业数据库建立中的应用;(3)在渔业资源生态评价中的应用:包括渔业资源的时空分布模拟、环境变化对渔业资源的影响研究、生态热点区的确定(产卵场、迁移通道等)、鱼类关键生境评估、渔业资源量大小估算;(4)在渔业管理及决策中的应用:包括建立海洋保护区(Marine Protected Areas,MPAs)和进行基于生态系统的渔业管理(Ecosystem-Based Fishery Management,EBFM)。相较传统的方法而言,尽管空间信息技术具有诸多优势,但目前其在渔业生态监测和评价中也面临不少挑战:如数据的有效采集、海量多源数据库需要大量的调整和重构等。今后,渔业资源保护趋向运用整体生态系统方法进行监测和评价,而这需要通过利用多种空间信息技术才能更好地得以实现。  相似文献   

10.
新疆开都河鱼类区系组成与分布   总被引:1,自引:0,他引:1  
2004~2013年间对新疆开都河鱼类的种类和分布进行了10次野外调查,根据不同的海拔和生境,设置鱼类采集点22个,共采集鱼类标本1 990号,分属3目7科19种。其中土著鱼类3种,由裂腹鱼类和高原鳅类构成;外来鱼类16种,隶属2目5科16属,鲤科鱼类占绝对优势。与历史资料相比,土著鱼类中扁吻鱼(Aspiorhynchus laticeps)、塔里木裂腹鱼(Schiorhorax biddulphi)、扁嘴裂腹鱼(Schiorhorax esocinu)和高原裸裂尻鱼(Schiorhorax stoliczkae Steindachner)未见,而外来鱼类则增加了12种,形成了土著鱼类与外来鱼类共存的生态格局;开都河鱼类区系及分布有较明显的多样性和地域性,受人为干扰、水温及大坝阻隔的影响,出山口后河段以外来鱼类占主导,而出山口以上河段则仍以土著鱼类为主,二者在空间分布上有较明显的界限。开都河鱼类区系的演变过程可分为两个阶段:稳定和发展阶段;人工引种后剧烈变化阶段。土著鱼类的保护管理应由政府牵头,进行保护、监测、科研等规划的顶层设计,突出栖息地生境的保护。  相似文献   

11.
  1. Freshwater communities and especially pond‐breeding amphibians are extremely vulnerable to land‐use change, alien species introductions and the use of pesticides or other toxic chemicals, as reflected in their worldwide decline. Effective conservation and management of ponds requires a better understanding of the biotic and abiotic factors that shape diversity patterns and species distribution, especially in cases of habitat loss
  2. The present study aimed to reveal and classify which pond and landscape characteristics are the most important determinants for the occurrence patterns of amphibian species as well as for the overall amphibian species richness in an urban pond network. To achieve this aim, 17 biotic and abiotic variables were measured for 61 ponds and the dataset was analysed by means of a machine‐learning approach, suitability indices and co‐occurrence modelling
  3. The highest probability of Triturus macedonicus occurrence was found at fishless artificial and semi‐natural ponds. The persistence of Lissotriton graecus in ponds was predicted by high pond connectivity and the absence of fish reflecting the species dispersive potential. Pelophylax kurtmuelleri showed a higher probability of occurrence with increased pond connectivity and macrophyte cover.
  4. Amphibian species richness was higher in fishless ponds with well‐oxygenated waters located in sites with a low to intermediate road density network. Ponds categorized as ‘average’ in terms of newt suitability were more frequently inhabited by fish than Triturus macedonicus. Alien fish species showed negative associations with both newt species, while both newt species showed a positive association between them.
  5. The results support the view that conserving a greater number of water bodies with increased landscape connectivity and without any fish presence could provide amphibian species with alternative habitat choices, especially in sites with human pressure where pond stability is at stake owing to continuous landscape changes.
  相似文献   

12.
1. Macrophyte assemblages from 50 ponds throughout the Northumberland coastal plain were surveyed together with adjacent landscape, pond morphology and physical and chemical variables. 2. TWINSPAN classification and CANOCO ordinations suggested that, whilst distinct macrophyte assemblages recurred, relationships of assemblages to environmental variables were weak. Geographical variables (northing, easting and altitude) plus extent of drying out were the most important variables in the CANOCO ordination linking pond types and environmental factors. Most assemblages could be found across a wide range of conditions. Classifications using only aquatic or emergent taxa gave different results. 3. Regression analyses suggested that total species richness of aquatic taxa increased with greater area of deeper water and pH. Emergent taxa richness increased with pond area, areas of deeper water and drying down, and decreased with altitude. The level of prediction was weak. 4. Pond types, defined by their macrophytes, were dispersed throughout the region and interspersed so that adjacent ponds often supported different assemblages. No habitat or locale supported unique types or unusual variety. 5. Local, anecdotal classifications of pond types in Northumberland, e.g. ‘subsidence ponds’, proved unreliable. Classification of ponds using macrophytes suggested greater biodisparity than such simplistic categories. The two main approaches to pond assessment (spatial surveys and ecological classification) need to be combined for sound assessment of the local status of ponds. This would benefit regional selection of pond types for conservation. © 1998 John Wiley & Sons, Ltd.  相似文献   

13.
14.
以扬州市2002年、2007年、2013年的遥感影像为数据源,通过解译获得了扬州市湿地资源分布图,运用转移矩阵法及景观格局指数法对2002-2013年间扬州市湿地动态变化及景观格局演变进行分析,并利用主成分分析法对其驱动力进行探究。结果表明,扬州市2002-2013年湿地面积呈逐年下降趋势,2007年比2002年减少13.69 km2,降幅1.1%;2013年比2007年减少43.23 km2,降幅3.3%。2013年与2002年相比,河流面积稍有减少,降幅为5.6%;滩地面积增加73.2%;库塘面积所占比重由49.84%上升到55.37%,面积增加6.2%;湖泊面积降幅29.7%,所占比重由32.83%下降到24.14%。2002、2007、2013年,各湿地斑块所占景观面积比均为库塘>湖泊>河流>滩地。景观格局指数分析表明,湖泊、滩地及库塘呈现不同程度的破碎化,而河流湿地斑块形状趋于规则且连通性较好。扬州市湿地景观整体呈破碎化趋势,湿地斑块形状趋于复杂,景观多样性增加,各类型湿地呈均衡化趋势发展。社会经济发展、人口增加、第二产业比重及降雨量变化是导致湿地景观格局变化的主要驱动力。  相似文献   

15.
  1. Modification and loss of natural habitats caused by human activities are among the main drivers of biodiversity decline worldwide. To evaluate how land‐use changes affect species diversity at different spatial scales, amphibians represent an excellent group given that their complex life cycle requires both aquatic and terrestrial habitats.
  2. In this study, the influence of wetland characteristics and surrounding landscape features on richness and functional diversity of anurans was investigated in 26 natural wetlands in a human‐modified landscape within the Southern Andean Yungas.
  3. The analysis was performed at two spatial scales: wetland scale (the breeding pond structure) and the surrounding landscape scale. The classification of the landscape was limited to land uses modified by human activities within concentric circular buffers (radius = 0.1, 0.2, 0.5, and 1 km) centred on each breeding pond.
  4. Generalized linear models were applied to investigate the relationship between environmental variables measured at different scales and anuran species richness and functional diversity, respectively.
  5. Pond area best explained the observed variation in both diversity measures, which is consistent with other studies on anuran diversity in disturbed landscapes. In contrast to regression models including landscape scale variables only, integrated models (which included variables on both scales) highly improved model fit.
  6. Conservation strategies for anuran species diversity in these altered Andean Yungas forests should include efforts to maintain or restore aquatic habitats (e.g. breeding ponds) placed within suitable landscapes.
  7. Successful long‐term management will require an understanding of relationships between habitat characteristics at different spatial scales to identify variables that relate to species diversity in such heterogeneous habitats.
  相似文献   

16.
  1. Global environmental change is threatening freshwater biodiversity with ecological impacts predicted to be particularly severe in high-altitude regions. Despite this, an ecological understanding of high-altitude pond networks remains patchy, with only limited knowledge of the environmental and spatial predictors of taxonomic and functional diversity. Moreover, previous studies of pond ecosystems have focused primarily on taxonomic richness and largely overlooked functional diversity.
  2. This study examined the influence of local environmental and spatial factors on taxonomic and functional α and β diversity (including the turnover and nestedness-resultant components) of 17 high-altitude (~2,500 m above sea level) pond macroinvertebrate communities, in the Macun Cirque, Switzerland.
  3. Spatial processes (pond connectivity) were important drivers for taxonomic α diversity, while local environmental variables (pond permanence and surface area) were important determinants of functional α diversity. Species turnover was the most important component of β diversity for taxonomic composition, and functional composition demonstrated a nested spatial pattern.
  4. Variation in taxonomic and functional composition (and the turnover and nestedness components of β diversity) were determined by local environmental variables despite the limited environmental gradients within the pond network. No significant effects of spatial variables on community composition were recorded for either facet of diversity, indicating that compositional variation was determined at a local scale. Water temperature, depth and pond permanence were consistently the most important measured drivers of diversity.
  5. Given the importance of both spatial and environmental variables in structuring taxonomic and functional diversity, landscape-scale conservation and management activities that aim to improve or protect high-altitude freshwater biodiversity should focus on maintaining connectivity among ponds and environmental heterogeneity, particularly pond surface area, water depth, and hydroperiod. Understanding the mechanisms driving taxonomic and functional diversity will be critically important for the management and conservation of macroinvertebrate communities in high-altitude pond networks in the face of climatic warming.
  相似文献   

17.
  • 1. Habitat heterogeneity has many implications in ecological assessment studies. On one hand it provides varying niches for organisms, increasing diversity. On the other hand, the inherent spatial variability of structurally complex systems may overlap with ecological condition making it difficult to disentangle the effects of perturbation. This study investigated the combined and single effects of habitat and pond condition on the macroinvertebrate assemblages of 35 ponds located in north‐west Spain and spanning a range of water quality and habitat characteristics.
  • 2. Macroinvertebrate communities and several environmental variables were sampled in the summer of 2004 or 2003. Samples were collected from four dominant habitats (vegetated shores, shores without vegetation, submerged vegetation, bare sediments) following a time‐limited sampling. Non‐metric multidimensional scaling and two‐way crossed ANOSIM were used to investigate the taxonomic and functional differences in macroinvertebrate assemblage structure among habitats (four types) and pond conditions (optimal, good, moderate, poor, very poor). To investigate the individual and combined effects of pond condition and habitat on several diversity measures GLM models were used. In addition, the accuracy of two sampling designs — stratified and multihabitat — was compared using the CVs of seven macroinvertebrate attributes.
  • 3. Results showed that macroinvertebrate communities differed significantly, albeit weakly, among habitat types and pond condition categories. In particular, the abundance of several Chironomidae genera, rarefied richness and Shannon index decreased both in perturbed systems and bare sediments, whereas no marked differences occurred between shores and submerged vegetation.
  • 4. We suggest that a multihabitat approach together with the use of community attributes not (or slightly) affected by habitat type will provide more comparable results across ponds than a stratified approach or observation of the whole community, especially in ponds where degradation leads to habitat loss.Copyright © 2009 John Wiley & Sons, Ltd.
  相似文献   

18.
近年来,随着全球气候变暖、水资源开发利用与人类活动的不断加剧,湄公河流域水生态系统健康状况正遭受着严重威胁,其区域社会经济发展呈严峻态势。以湄公河干流老挝沙湾拿吉-柬埔寨桔井段及重要支流为研究区域,结合生境要素空间异质性,利用空间聚类法对其进行水生态功能分区研究。研究结果表明,基于区域地貌特征提取的水生态2个一级区能较好的体现区域水资源分配状况和供给功能;基于流域水系河网、土壤及土地利用特征提取的5个二级分区能反映人类活动对区域水生生境及水质的影响。水文、水生生物及水质数据分别验证了分区结果的合理性。研究结果可为跨界河流水资源管理和水生态环境保护提供了科学支撑。  相似文献   

19.
1. Despite their importance for aquatic biodiversity, ponds are among the most vulnerable freshwater habitats. Owing to their isolation in terrestrial environments, ponds are expected to be relatively well protected from biological invasions, but this depends on many factors. 2. The purpose of this study was to examine the influence of a range of variables (water quality, habitat, and landscape attributes) on the colonization of discrete ponds by a widespread aquatic invader, the red swamp crayfish Procambarus clarkii, which can disperse overland. 3. Investigations were conducted in two networks of ponds, each located in close proximity to a large invaded marsh. The two marshes under study differed in the length of time since the crayfish were introduced. 4. The proportions of colonized ponds and crayfish abundances were moderate in both networks, but higher in the network that had been invaded first. In both networks the distance to the marsh was the main predictor of pond colonization, considering similar energy costs to cross aquatic and terrestrial habitats for the recently invaded network, but assuming that dispersal was 25 times costlier across the terrestrial matrix than via streams for the earlier invaded network. Pond characteristics had no influence on crayfish occurrence in either network. Furthermore, predictions of pond invasion were lower for the recently invaded network. 5. The importance of the distance to the marsh indicates that natural dispersal was the main process of pond colonization by crayfish. Findings also suggested that overland dispersal was rare and costly. By contrast, streams were probably significant in facilitating crayfish dispersal. Differences between the two networks might arise from an invasion process still in progress in the recently invaded network. 6. From a management viewpoint, local actions are encouraged to prevent the spread of crayfish via streams. In addition, broader‐scale actions to mitigate other human disturbances would improve the outlook for pond biodiversity.  相似文献   

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