共查询到20条相似文献,搜索用时 109 毫秒
1.
2.
3.
重金属超积累植物及其植物修复技术是当前国内外学术界研究的热点领域之一。目前已有As、Se、Cr、Cu、Mn、Pb、Zn等超积累植物被发现的报道。就国内外植物修复技术领域的研究进展进行了综述,阐述了迄今报道的超积累植物研究动态与前景。 相似文献
4.
5.
黄山地区主要能源植物及其开发利用策略 总被引:1,自引:0,他引:1
植物能源是一种清洁、方便的可替代能源,发展植物能源是解决矿石能源危机的可行措施。黄山的植物资源十分丰富,有高等植物222科827属1800余种,其中能源植物有20余种。介绍了黄山地区主要能源植物,提出了其开发利用策略。 相似文献
6.
植物在人工湿地中的作用及物种选择 总被引:13,自引:0,他引:13
本文主要阐述了植物在人工湿地中的作用和选取植物的一些原则,并分析了今后所研究的重点。植物在人工湿地中起着非常重要的作用,不但可以去除污染物质,而且具有生态美学和经济价值;选择植物应考虑植物的净化能力、适应性等因素。最后提出了植物研究需要加强的地方。 相似文献
7.
8.
9.
介绍了植物护坡技术的基本原理和优点,探讨了适合高盐碱堤坝护坡的植物筛选、植物配置和栽植技术,提出了相应的配套措施,分析了当前研究存在的主要问题。 相似文献
10.
11.
Information on distribution and relative abundance of species is integral to sustainable management, especially if they are to be harvested for subsistence or commerce. In northern Australia, natural landscapes are vast, centers of population few, access is difficult, and Aboriginal resource centers and communities have limited funds and infrastructure. Consequently defining distribution and relative abundance by comprehensive ground survey is difficult and expensive. This highlights the need for simple, cheap, automated methodologies to predict the distribution of species in use, or having potential for use, in commercial enterprise. The technique applied here uses a Geographic Information System (GIS) to make predictions of probability of occurrence using an inductive modeling technique based on Bayes' theorem. The study area is in the Maningrida region, central Arnhem Land, in the Northern Territory, Australia. The species examined, Cycas arnhemica and Brachychiton diversifolius, are currently being 'wild harvested' in commercial trials, involving sale of decorative plants and use as carving wood, respectively. This study involved limited and relatively simple ground surveys requiring approximately 7 days of effort for each species. The overall model performance was evaluated using Cohen's kappa statistics. The predictive ability of the model for C. arnhemica was classified as moderate and for B. diversifolius as fair. The difference in model performance can be attributed to the pattern of distribution of these species. C. arnhemica tends to occur in a clumped distribution due to relatively short distance dispersal of its large seeds and vegetative growth from long-lived rhizomes, while B. diversifolius seeds are smaller and more widely dispersed across the landscape. The output from analysis predicts trends in species distribution that are consistent with independent on-site sampling for each species and therefore should prove useful in gauging the extent of resource availability. However, some caution needs to be applied as the models tend to over predict presence which is a function of distribution patterns and of other variables operating in the landscape such as fire histories which were not included in the model due to limited availability of data. 相似文献
12.
13.
A variety of species was observed as either visitors, permanent, or summer residents on surface mines with different ecological adaptations. Passerine species were the most prevalent of the 25 families represented. Bird communities as well as individual species were correlated with the structure and species of vegetation on the mines. The composition of the bird communities changed in response to successional vegetation stages from grassland to forest communities. 相似文献
14.
/ For regional analyses of species imperilment patterns, data on species distributions are available from the U.S. Fish and Wildlife Service and from the state heritage programs. We compared these two different databases as sources of best available information for regional analyses of patterns of aquatic species imperilment for 132 counties in the southern Appalachians and examined patterns produced from the databases. The heritage program database contained information about a greater number of imperiled species because species need not be federally listed as threatened or endangered to be included in this database. In the southern Appalachians, about half of imperiled molluscs and about one-fourth of imperiled fish were listed as threatened or endangered; much smaller proportions of other taxonomic groups were federally listed. Most threatened and endangered species appeared on both lists, but for about 40% of the species inconsistencies exist, notably a lack of recent records in the heritage program dataset. Numbers of species in each county were significantly different between the two datasets for Georgia, Tennessee, and Virginia, where the largest number of threatened and endangered species reside. Nevertheless, some counties always appeared as centers of imperilment, and the general spatial patterns of imperilment were similar. 相似文献
15.
Teea Kortetmäki 《Journal of Agricultural and Environmental Ethics》2018,31(3):307-323
In this article, I apply the environmental or expanded capabilities approach to species and examine whether species as wholes can have capabilities and what are the implications if they can. The examination provides support for the claim that species as evolutionary groups can possess capabilities. They have integrity, which refers to the functionings that enable the self-making and development (evolvement) of species, and it is conceptually possible to identify capabilities that essentially enable or contribute to species integrity. One central capability for species can be identified from conservation literature: adaptive capacity, the ability of species to react to environmental changes by self-regulative evolution. After constructing the main argument that species can have capabilities and that they possess the capability to adaptive capacity, I shortly expound on the implications of these claims. It turns out that there are at least three different ways to apply the notion, and that the claim ‘species have capabilities’ does not entail that species are necessarily recipients of justice. 相似文献
16.
Valuing improvements to threatened and endangered marine species: an application of stated preference choice experiments 总被引:1,自引:0,他引:1
Non-market valuation research has produced value estimates for over forty threatened and endangered (T&E) species, including mammals, fish, birds, and crustaceans. Increasingly, Stated Preference Choice Experiments (SPCE) are utilized for valuation, as the format offers flexibility for policy analysis and may reduce certain types of response biases relative to the more traditional Contingent Valuation method. Additionally, SPCE formats can allow respondents to make trade-offs among multiple species, providing information on the distinctiveness of preferences for different T&E species. In this paper we present results of an SPCE involving three U.S. Endangered Species Act (ESA)-listed species: the Puget Sound Chinook salmon, the Hawaiian monk seal, and the smalltooth sawfish. We estimate willingness-to-pay (WTP) values for improving each species' ESA listing status and statistically compare these values between the three species using a method of convolutions approach. Our results suggest that respondents have distinct preferences for the three species, and that WTP estimates differ depending on the species and the level of improvement to their ESA status. Our results should be of interest to researchers and policy-makers, as we provide value estimates for three species that have limited, if any, estimates available in the economics literature, as well as new information about the way respondents make trade-offs among three taxonomically different species. 相似文献
17.
裸果木是我国国家重点保护野生植物,受自然因素和人类活动的影响,其分布区日益缩小。综述了目前国内外对于裸果木的研究现状,提出了研究展望,以期对裸果木的保护提供依据。 相似文献
18.
Waite TA 《Environmental management》2007,40(3):476-480
Bushmeat hunting, a key source of dietary protein, has been implicated as a major extinction threat to tropical vertebrate
species in West Africa. Ideally, any such hunting of wild species should be done sustainably, with off-take levels low enough
to ensure viability of harvested species. Recent work purports to show that a mature bushmeat market in a major city in Ghana
operates sustainably after depletion of vulnerable, slow-reproducing species (Cowlishaw and others 2005). I revisit two aspects of this work. First, I retest the prediction that larger species are transported to the market from
greater distances, as expected if overexploitation depletes large species close to the city. Cowlishaw and others failed to
find a significantly positive relationship between species-specific body mass and distance between capture site and the market.
However, my reanalysis provides evidence for a positive relationship after all, consistent with unsustainable harvesting.
In particular, ungulate species were harvested significantly farther from the market than smaller-bodied rodent species. Second,
I caution that just because species “persist” in the marketplace in no way implies that they can withstand hunting pressure
elsewhere and so should be of little concern to conservationists. I reveal that such species, despite their high intrinsic
rates of population growth, are not robust elsewhere. Several of them have disappeared from a network of protected areas in
Ghana (Brashares and others 2001). I show that faster-reproducing species are not necessarily more likely to persist in protected areas. The mere presence
of fast-reproducing species in a mature bushmeat market should not be construed as generalizable robustness; criteria for
ecological sustainability should ensure viability; and harvested species should be robust, not highly prone to extinction,
in protected areas. 相似文献
19.
Betsabé Ruiz-Guerra Noé Velázquez Rosas Juan Carlos López-Acosta 《Environmental management》2014,54(3):656-667
This study analyzes the potential uses of live fences and pastures as reservoirs of plant diversity for two regions with different management histories, Los Tuxtlas (LT) and Uxpanapa (UX), Veracruz, México. We studied two habitats, live fences and pastures, analyzed their species richness, diversity, structure and plant composition and classified species according to plant regeneration modes (light-demanding and shade tolerant), seed dispersal syndrome and their local uses. We recorded 62 species of trees at LT and 48 at UX. Live fences were more diverse than pastures in both regions. The LT site showed to analyze the relationship a higher diversity of plants in regeneration stages than the one at UX. However, UX had higher diversity of adult plants in the pastures than LT. Composition and structure of live fences were different between regions, as well as within live fences and pastures, 53 % of species were light-demanding and 40 % were shade tolerant; 70 % of the species were dispersed by birds. Differences between sites are associated with the modifications in live fences structure, which changed according to managerial practices and the use of local species; this may influence plant regeneration modes as well as the visits of avian dispersal agents. In LT, all species found in live fences were useful to humans, whereas in UX, less than half were used by the local population. Our results underline the importance of live fences and isolated trees in pasture habitats as potential sites to host native and useful species from tropical rain forests in livestock landscapes. 相似文献
20.
本文根据我国珍稀濒危植物的保护现状和管理工作中存在的问题,系统地探讨了加强我国珍稀濒危植物和野生植物资源保护的政策措施。文中提出一系列具体、有效的政策构思,以及建立政府有关主管部门对珍稀濒危植物协调管理的体制等。 相似文献