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1.
供水型水库底栖动物完整性指数的构建   总被引:1,自引:0,他引:1       下载免费PDF全文
为给水源地水库的生态风险评估提供科学依据和决策支持,根据浙江省和湖北省几个典型水库的调查数据,构建了底栖动物完整性指数(B-IBI)。参考相关文献及调研选取了32个备选参数,经统计分析筛选出8个指示能力较强的参数,构建B-IBI指标体系,分别为香侬-维纳多样性指数(Shan2)、捕食者类群数量百分比(Pred-Pct)、寡毛类物种数百分比(%OligoTax)、非水生昆虫数量百分比(NonInPct)、Hilsenhoff生物指数(HBI)、收集者物种数百分比(%CllctTax)、收集者数量百分比(CllctPct)和平均物种数量(RichnessPerTaxon)。确立了水库生态系统健康评价标准,并与潜在环境梯度进行了相关性分析。结果表明,该指数很好地反映了潜在环境梯度,用于供水型水库的水生态系统健康评估较为合适。  相似文献
2.
黑龙江省雨热同季,农业水资源属于我国北方较多地区,但降水分布不均,春旱和夏涝对农业生产影响较大。嫩江和松花江干流水对工农业生产、人们生活和改善生态环境均有较大影响,关键是要提高控制率。松花江干流外来过境水资源、东部地下水资源和国境界河水资源等均有较大开发潜力。农业水资源丰富的地区,应优先发展水稻。农业水资源较少的地区发展旱田节水灌溉,应优先选择菜瓜果类高效益作物和对生产影响较大的种子苗木等,扩大玉米催芽坐水种面积,种植附加值较高的经济作物。  相似文献
3.
党中央、国务院十分重视水利建设工作,数年的中央"一号文件"多次提到建立由国家、地方和农民共同负担的水利设施建设投入长效机制。2011年中央"一号文件"中提出加大公共财政对水利的投入,将水利作为公共财政投入的重点领域,这些为我国加快推动水利建设提供了难得的历史机遇。本文分析了国外发达国家和国内一些地区的经验,总结提出对我国水利建设的启示。  相似文献
4.
水足迹指一个国家、一个地区或一个人,在一定时间内消费的所有产品和服务所需要的水资源数量。本文运用该理论对六盘水市水资源进行了水足迹和相关指标的计算。结果表明:⑴六盘水市水足迹从2005年的37.51亿m3上升到2007年的41.56亿m3,其后又由2007年的41.56亿m3下降到2010年的39.54亿m3,这一变化趋势与农业水足迹用水量和工业水足迹用水量一致,水足迹以农业水足迹用水量和工业水足迹用水量为主,两者的总量占到了总用水量的96%以上;⑵六盘水市水资源强度呈不断下降的趋势,从2005年的1804.06m3/万元下降到2010年的789.71 m3/万元,有利于提高水资源的利用率;⑶2006年、2010年六盘水水资源压力指数超过1,只有采取多渠道开发水资源、提高工业用水的重复利用率、加大污水治理和水体污染防治力度、开展节水技术等措施,才能确保六盘水市水资源安全。  相似文献
5.
节约型渔业发展战略是辽宁渔业可持续发展的基本战略。其研究不仅具有经济意义,而且具有社会、生态意义。文章阐述了发展节约型渔业的意义和节约型渔业与传统渔业的区别;分析了辽宁发展节约型渔业的障碍;提出了辽宁节约型渔业发展战略措施。  相似文献
6.
Freshwater fish populations in England and Wales form an important resource with up to 2.2 million anglers involved in the recreational fishery. The resource consists principally of indigenous and naturalised cyprinids, and strongholds of species endangered elsewhere in Europe. Each component is under pressure from a range of sources including water abstraction and climate change. Water resources are under significant pressure and droughts in parts of England and Wales exposed the fragility of water supply systems. Climate change is a major concern, driving a re-assessment of water supply yields. There are no objective methods available to predict changes in fish communities likely to arise from different water resource management options, except for simple systems. It is difficult to manage water resources using anything other than a precautionary approach. Accurate assessment of environmental requirements are required to strike the right balance between the needs of aquatic ecosystems and of economic efficiency.  相似文献
7.
8.
湿地淡水资源供给是一项重要的生态系统服务功能,主要包括城镇居民生活用水、工业(矿业)用水和农业用水三大部分。本文以2013年吉林省湿地淡水供给资源作为研究对象,采用市场价值法,进行省域尺度上与人类生活、工业生产等关系密切的淡水供给服务的识别和核算,研究吉林省不同湿地类型和不同行政区的淡水资源供给量和淡水资源供给价值,分析其淡水资源供给的空间分布及其贡献率,得出2013年吉林省湿地淡水资源供给总量为27.71×108m3,其中,湖泊湿地供给淡水量约为8.06×108m3/年,河流湿地供给淡水量约为6.04×108m3/年,人工湿地供给淡水量约为4.00×108m3/年,沼泽湿地供给淡水量约为2.71×108m3/年;核算吉林省湿地淡水资源供给总价值为83.84亿元/年,其中,湖泊湿地占38.73%,河流湿地29.01%,人工湿地占19.25%,而沼泽湿地所占比例最小,为13.01%。在各组成城市中湿地淡水资源供给价值以松原市最大,其核算价值为26.28亿元/年,占总价值的31.34%,而白山市最小,为2.6亿元/年,占总价值的3.11%。本研究中利用价值量化的方法表征淡水供给为吉林省发展提供的经济价值,对吉林省水资源优化配置、促使社会经济和生态环境协调发展和湿地保护具有重要的理论和实践意义。  相似文献
9.
  1. Patterns of connectivity are critical to structuring both spatial and temporal variation in the composition of species populations and assemblages. Water resource development has an important impact on longitudinal connectivity in rivers, and disrupts natural patterns of dispersal of individuals between segments of the river network. Consequently, artificial barriers alter the structure, size and distribution of species populations leading to impacts on aquatic biodiversity.
  2. Quantitative assessment of the ecological effects of connectivity alteration is necessary to develop effective conservation plans to manage the impacts of anthropogenic fragmentation. Connectivity alteration is a complex environmental disturbance because the potential scale of impact is dependent on the spatial scale at which biota undergo life‐history processes such as spawning and recruitment. Few river networks have single migration barriers, meaning that multiple points of fragmentation are present and have potentially interacting effects. Therefore, conventional ‘control–impact’ approaches to impact assessment may be inappropriate or confounded. Furthermore, monitoring patterns of fish population or assemblage structure moving through fish passage facilities alone creates a mismatch between the spatial scale of impact and assessment of water resource development.
  3. This paper uses a case study in subtropical Australia to highlight three potential approaches to increasing inference of the impact of fragmentation by barriers on riverine fish. Thorough understanding of life‐history and dispersal ecology of fish is necessary to understand and predict the consequences of fragmentation, and comparing patterns of distribution among species with different migration requirements can identify sources of fragmentation. Monitoring patterns in fish assemblages at both the barrier and river network scale increases the strength of inference of the effects of connectivity alteration and management. Experimental removal of artificial barriers would assist in determining the effect of fragmentation by restoring connectivity. Such approaches would improve predictions of connectivity management and underlying drivers of aquatic biodiversity.
Copyright © 2013 John Wiley & Sons, Ltd.  相似文献
10.
Inland capture fisheries provide food for nearly a billion people and are important in the livelihoods of millions of households worldwide. Although there are limitations to evaluating many of the contributions made by inland capture fisheries, there is growing recognition by the international community that these services make critical contributions, most notably to food security and livelihoods in rural populations in those low‐income countries with extensive freshwater resources. With the increasing appreciation of the key role of inland fisheries to the health and well‐being of human populations globally, the Food and Agriculture Organization of the United Nations and Michigan State University convened the 2015 global conference, Freshwater, fish, and the future – cross‐sectoral approaches to sustain livelihoods, food security, and aquatic ecosystems. What emerged from the interactions between inland fisheries’ scientists, resource managers, policymakers and community representatives from across the world was a forward‐looking call to action culminating with the 2015 Rome Declaration “Ten Steps to Responsible Inland Fisheries” (FAO & MSU, Rome declaration on responsible inland fisheries: 5735E/1/06.16). Four years after this landmark conference and declaration, we seek to advance discussion on the “Ten Steps,” namely what successful implementation looks like, assess current examples of implementation, suggest potential signals of progress and provide some specific, indicative examples of progress for each step. While there are promising signs of progress, we conclude that there remains a strong need to galvanize momentum for sustained action to ensure that inland fish and fisheries are accounted for and incorporated into broader water resource management discussions and frameworks.  相似文献
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