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1.
两河口水电站工程建设改变了工程河段的自然生态环境,导致原有鱼类产卵场被部分淹没。修建人工鱼类产卵场是水生生态生境修复的重要措施之一。两河口人工鱼类产卵场位于库尾和平乡河段,总面积1.6hm2。根据流场数值模拟,生境适宜度分析成果,产卵场分成AB两个大区,其中A区为裂腹鱼类产卵场,B区为鮡科鱼类、鳅科鱼类产卵场。A区裂腹鱼类产卵场分为Ⅰ区,Ⅱ区,产卵对象分别为短须裂腹鱼、长丝裂腹鱼等裂腹鱼类以及厚唇裸重唇鱼与软刺裸裂尻鱼;B区鮡科鱼类、鳅科鱼类产卵场分为Ⅲ区与Ⅳ区,产卵对象分别为鮡科鱼类及鳅科鱼类。  相似文献   

2.
我国河鲀鱼资源及其开发利用   总被引:2,自引:0,他引:2  
东方是我国重要的鱼类资源。介绍了河鱼的利用价值及其资源的利用状况 ,探讨了河鱼的开发前景和开发利用途径。  相似文献   

3.
据调查鉴定,流经广西河池地区的红水河、龙江和四堡河的鱼类资源有156种,分隶7目19科97属。其中有91种为本区第一次记录,有土著鱼类153种,并发现金线鲃属鱼类有4个新种。  相似文献   

4.
从1963年开始,四川省先后建立了卧龙、唐家河、王郎、白河和喇叭河等15个不同类型的自然保护区。保护区面积共有51.34万ha,占四川省幅员面积的0.9%。我们先后对保护区的鱼类进行了调查和访问,获鱼类标本468号,经鉴定有5目9科27属35种,其结果如下。1 保护区的溪河特点与鱼类组成1.1 特点唐家河、王郎、小寨子沟、白河、九寨沟、黄  相似文献   

5.
青海省土著经济鱼类资源合理开发意见   总被引:1,自引:0,他引:1  
青海省具有经济价值的土著鱼类,主要是鲤科裂腹鱼亚科中的种类,共约20余种,广泛分布在青海省各种水体之中,尤以黄河、长江水系及其附属水体较为集中.其中青海湖裸鲤(湟鱼)、花斑裸鲤(大嘴鱼)和极边扁咽齿鱼(小嘴鱼),是青海省水产业的支柱.它们不但能忍受高寒的恶劣环境,甚至在较高的盐碱水体中也能生存,是一群生活力很强的鱼类.这3种鱼类生长速度皆较慢,一般5年左右长250克,10年左右达500克.繁殖习性相似,卵和卵巢皆有毒,为沉性卵.每年5—8月为繁殖季节,鱼群皆溯河繁殖.花斑裸鲤和极边扁咽齿鱼虽生活在同一水体之中,但各有自己的产卵场范围,绝不混杂.3种土著鱼类中以极边扁咽齿鱼的相对繁殖力最高,为55.5粒/克,花斑裸鲤和青海湖裸鲤较低,分别为29.7粒/克和31.0粒/克.  相似文献   

6.
王连龙  徐海根  蒋明康 《四川环境》2004,23(5):25-27,46
天全河珍稀鱼类自然保护区是四川省珍稀鱼类和经济鱼类的重要保护区,保护区及其周边地区有高等植物100多种,脊椎动物200余种,其中鱼类5目8科26属39种。但目前保护区面临一系列的问题和困难,如保护区组织机构不健全,管理水平低下,滥捕偷捕现象突出,与社会矛盾较大,资金不足等等。本文针对这些问题,从可持续发展的角度提出了相应的对策,如完善保护区的管理机构,健全社区参与机制,发展生态旅游,适度利用保护区的相关自然资源等。  相似文献   

7.
杨富亿 《资源开发与市场》1998,14(4):161-162,165
根据1990-1994年调查结果表明,我国大兴岭北部现有淡水鱼类计7目5亚目14科,14亚科47属68种,其中经济鱼类22种。与80年代初期相比,有8目2亚目10科2亚科29属33种鱼类未采集到标本,经济鱼类资源少了17种。  相似文献   

8.
云南山高谷深,地貌复杂,江河纵横,湖泊众多,鱼类资源非常丰富,达400多种,约占全国淡水鱼类的50%,分隶10目、27科、138属,其中国内仅见于云南的有4个特有科,40个特有属,240个特有种。目前,由于鱼类的生活环境受到严重的干扰和破坏,有部分种类濒临灭绝。为保护鱼类资源和生态系统的平衡,根据国家制定的濒危物种等级标准,云南省把37种濒危鱼类列为保护对象(附表)。  相似文献   

9.
青海湖自1958年开发以来,至1984年其鱼产量均占全省鱼产量的85%—95%。80年代后,扎陵湖、鄂陵湖和可鲁克湖的鱼类资源相继开发,1985年之后全省池塘养鱼又有较大规模的发展,  相似文献   

10.
《环境教育》2005,(10):56-57
片名:《海底总动员》导演:佚名领衔主演:狮子鱼/黄花鱼/刺河豚/穗鳍鱼客串:毒疣鱼/黄貂鱼谁护卫谁了。慈父就这样满载着吸附周身的幼鱼,游向深海中的安全地带。鱼类的“金嗓子”一般人总认为鱼类是沉默寡语的,其实所有的鱼类不仅都能发音,而且还不乏“金嗓子”。人们爱吃的黄花  相似文献   

11.
In recent years, there have been several calls for a UK government policy towards materials. This paper takes some proposals regarding conservation, and applies them to the UK copper-using industries. The main conclusions are that consumption is likely to decline anyway over the next ten years, but government attempts to influence the trend are likely to have little real effect — or else will be very costly, in money and other terms.  相似文献   

12.
This paper critically reflects on the challenges of engaging, proactively, in Corporate Social Responsibility (CSR) in oil-rich sub-Saharan Africa. Most of the region's oil production takes place in enclave-type environments offshore and in countries ruled by autocratic governments which generally exert minimal pressure on companies to embrace CSR. With companies having little sense of who to target in their local economic development policies and programs, there is always a possibility of ‘offshore CSR’ – recognized here as potentially-effective ideas for improving social welfare that linger within the enclave and never fully materialize – surfacing. The aim is to conceptualize and broaden understanding of the challenge of developing CSR programs in these settings, where there are no clear linkages to communities or local economies more generally.  相似文献   

13.
Many authors have suggested that Indigenous communities are especially vulnerable to the direct and indirect impacts of climate change, yet there remains a paucity of fine-grained geographic data on the particular impacts of climate change on specific places and on local communities, especially Australian Indigenous communities. While there are some recent studies being undertaken with Australia's Torres Strait Island people, our research takes up the issues of vulnerability and resilience with two Indigenous communities from different environments on the mainland in North Queensland. They are the Aboriginal peoples of the rainforest and reef environments of the Wet Tropics and the Aboriginal people of the discontiguous rainforest, grasslands, dry forests and marine environments of Cape York. The results demonstrate variability in their understandings of climate change and in their capacities to anticipate and manage its impacts, while at the same time illustrating some common held themes about environmental and cultural values, observed environmental change, attributions of cause and effect, and of climate in general.  相似文献   

14.
A classic research approach is to optimize experimental design and available resources. However, that approach does not guarantee that results will be useful. This article takes the view that research should not be undertaken unless there is assurance that final results will be significant to a level specified before any work is begun. Given that assurance, the relationship between cost and statistical significance is explored, a new approach to optimization s developed, and the use of models in research design is considered.  相似文献   

15.
Patagonia designs and distributes clothing for active use in the outdoors, and many of the people who work for Patagonia are avid climbers, skiers, surfers, and hikers. If the environment is destroyed, there will be no place for Patagonia's customers and employees to use its products. The types of products Patagonia makes and the personal commitment to the environment of its founder and employees make it unique. In the past few years, Patagonia has been systematically reviewing how the company's products and operations affect the environment. This article shows that even with Patagonia's unusual connection to the environment, the company is still finding that total quality environmental management is not easy. It takes analysis, planning, follow-through, and measurement; and even then, not all environmental efforts are successful.  相似文献   

16.
Private, voluntary eco-labelling and certification programmes are being developed for a number of industries to promote and verify higher environmental, economic and social standards. In some cases, these initiatives have developed regardless of whether there is initial, broad support within industry. This article seeks to identify some of the challenges inherent in the implementation of a sustainable development certification programme for the minerals and metals industry. The article looks for guidance from initiatives that are drawn for the most part from other resource industries, most notably forestry. While the article takes a Canadian perspective, many of the challenges raised in the article are also applicable internationally. The article concludes that stakeholders can learn from other resource industries if a decision is made to develop a certification programme for the minerals and metals industry. Crucial to the long-term success of such a programme will be the establishment of a true partnership among stakeholders throughout the initiative's development. Crown Copyright.  相似文献   

17.
Use and interaction of navigation strategies in regionalized environments   总被引:2,自引:0,他引:2  
In this work, three experiments are reported that studied the use and interaction of navigation strategies both during the learning of a virtual environment and during subsequent route planning tasks. Special interest concerned the role of regions within the environments. Results from Experiment 1 suggest that the regions are perceived and encoded in spatial memory very early during the process of learning an environment. During navigation such regional information could be used to overcome missing or imprecise spatial information on the detailed level. Experiments 2 and 3 studied the use and interaction of route planning strategies that are applied after an environment has been learned. Results suggest (i) that human route planning takes into account region-connectivity and is not based on place-connectivity alone, (ii) that route planning takes into account the distribution of multiple target locations and (iii) that route planning takes into account the complexity of alternative paths.  相似文献   

18.
Although conservation is an inherently transdisciplinary issue, there is much to be gained from examining the problem through an economics lens. Three benefits of such an approach are laid out in this paper. First, many of the drivers of environmental degradation are economic in origin, and the better we understand them, the better we can conserve ecosystems by reducing degradation. Second, economics offers us a when-to-stop rule, which is equivalent to a when-to-conserve rule. All economic production is based on the transformation of raw materials provided by nature. As the economic system grows in physical size, it necessarily displaces and degrades ecosystems. The marginal benefits of economic growth are diminishing, and the marginal costs of ecological degradation are increasing. Conceptually, we should stop economic growth and focus on conservation when the two are equal. Third, economics can help us understand how to efficiently and justly allocate resources toward conservation, and this paper lays out some basic principles for doing so. Unfortunately, the field of economics is dominated by neoclassical economics, which builds an analytical framework based on questionable assumptions and takes an excessively disciplinary and formalistic approach. Conservation is a complex problem, and analysis from individual disciplinary lenses can make important contributions to conservation only when the resulting insights are synthesized into a coherent vision of the whole. Fortunately, there are a number of emerging transdisciplines, such as ecological economics and environmental management, that are dedicated to this task.  相似文献   

19.
This paper assesses the efficacy and relevance of visitor payback as a tool for recreation management in the UK. Visitor payback is essentially a voluntary payment made by visitors towards conservation, differing significantly from the compulsory tourist or bed tax practised in other countries. Attention has recently focused on this technique as a means to supplement the limited funds available for conservation work. However, whilst there are several schemes operating in the UK, there is a dearth of published research that has critically reviewed the concept and operationalization of visitor payback. The research reported here utilizes primary and secondary data to include case studies, semi-structured interviews and focus groups. The findings reveal that visitor payback is a complex concept to evaluate, both in theory and practice, involving a range of benefits and disbenefits. Financial benefits appear less prevalent than the more esoteric ‘feel good’ factor, increased awareness about conservation and partnerships that are evident in payback schemes. Support for visitor payback varies considerably with visitors strongly receptive, whilst the tourism business interests are more cautious. It is concluded that visitor payback needs to be re-conceptualized in more positive terms as a ‘visitor investment scheme’ where conservation takes precedence over financial considerations. Further research is required to try and demystify the tourism business resistance to visitor payback as its potential seems somewhat constrained in the present climate.  相似文献   

20.
The major aim of this paper is to analyze how government funding affects the pace of progress in four states of the remediation process of contaminated sites, from basic risk classification to cleanup. We introduce a methodological framework that takes into account the unobserved site-heterogeneity and simultaneously models duration in the different states. The results show that although site-heterogeneity contributes to make remediation a slow process, the third state, from the elaborate risk classification to the cleanup start, is a particular bottleneck. Even if government funding can speed up the process at this state, the effect is minuscule compared to the amounts of funding required. Thus, there is a need for policy to also focus on other barriers to remediation.  相似文献   

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