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31.
32.
Rhett D Harrison Sylvester Tan Joshua B. Plotkin Ferry Slik Matteo Detto Tania Brenes Akira Itoh Stuart J. Davies 《Ecology letters》2013,16(5):687-694
Hunting affects a considerably greater area of the tropical forest biome than deforestation and logging combined. Often even large remote protected areas are depleted of a substantial proportion of their vertebrate fauna. However, understanding of the long‐term ecological consequences of defaunation in tropical forests remains poor. Using tree census data from a large‐scale plot monitored over a 15‐year period since the approximate onset of intense hunting, we provide a comprehensive assessment of the immediate consequences of defaunation for a tropical tree community. Our data strongly suggest that over‐hunting has engendered pervasive changes in tree population spatial structure and dynamics, leading to a consistent decline in local tree diversity over time. However, we do not find any support for suggestions that over‐hunting reduces above‐ground biomass or biomass accumulation rate in this forest. To maintain critical ecosystem processes in tropical forests increased efforts are required to protect and restore wildlife populations. 相似文献
33.
《Basic and Applied Ecology》2014,15(5):385-395
Wood-pastures are fragile ecosystems because they were formed by, and depend on specific, low-intensity multifunctional management. Although their ecological and cultural significance is high, wood-pastures are rapidly deteriorating all over Europe, mainly due to changing land use. We still lack a basic understanding of the ecological value of wood-pastures, and in which features they differ from other landscape elements. In this paper we investigated the ecological value of wood-pastures for passerine birds by (i) comparing bird assemblages of wood-pastures with those of closed forests and open pastures and (ii) exploring the relationships between variables describing wood-pastures and species traits of the bird assemblages. Our study region (Southern Transylvania, Romania) provides a unique opportunity to understand the importance of a traditional cultural and ecological environment for many different organisms. Wood-pastures had a higher overall number of bird species, and a higher spatial turnover in bird community composition than closed forests and open pastures. We found significant associations between bird species traits and habitat structural elements in wood-pastures such as large trees, oak- and pear trees and shrubs. Our findings suggest that traditional wood-pastures in Southern Transylvania have distinct and rich passerine bird communities. This richness is inextricably linked to the multifunctional, low-intensity land use traditionally applied in the wood-pastures that promotes high niche diversity. For effective conservation of the biodiversity of wood-pastures, a detailed understanding is needed of how different management regimes may influence the key structural elements of wood-pastures relevant for biodiversity and these should be protected. 相似文献
34.
Background. The 7th Framework Programme for Research and Technological Development is helping the European Union to prepare for an integrative system for intelligent management of biodiversity knowledge. The infrastructure that is envisaged and that will be further developed within the Programme “Horizon 2020” aims to provide open and free access to taxonomic information to anyone with a requirement for biodiversity data, without the need for individual consent of other persons or institutions. Open and free access to information will foster the re-use and improve the quality of data, will accelerate research, and will promote new types of research. Progress towards the goal of free and open access to content is hampered by numerous technical, economic, sociological, legal, and other factors. The present article addresses barriers to the open exchange of biodiversity knowledge that arise from European laws, in particular European legislation on copyright and database protection rights.We present a legal point of view as to what will be needed to bring distributed information together and facilitate its re-use by data mining, integration into semantic knowledge systems, and similar techniques. We address exceptions and limitations of copyright or database protection within Europe, and we point to the importance of data use agreements. We illustrate how exceptions and limitations have been transformed into national legislations within some European states to create inconsistencies that impede access to biodiversity information.Conclusions. The legal situation within the EU is unsatisfactory because there are inconsistencies among states that hamper the deployment of an open biodiversity knowledge management system. Scientists within the EU who work with copyright protected works or with protected databases have to be aware of regulations that vary from country to country. This is a major stumbling block to international collaboration and is an impediment to the open exchange of biodiversity knowledge. Such differences should be removed by unifying exceptions and limitations for research purposes in a binding, Europe-wide regulation. 相似文献
35.
36.
《Journal of biological education》2012,46(3):135-137
Conserving global biodiversity depends on public awareness, hence the vital role of education and the recent thinking that biodiversity conservation should form part of a new and general scientific literacy taught in schools. A crucial aspect of biodiversity conservation is species identification. Taxonomy in general, and identification keys in particular, are often seen as boring and outdated. Indeed, curricula focused on contemporary areas of biology tend to give a low priority to taxonomy or ignore it completely. However, concern for diminishing global biodiversity has provoked a renewed interest in both traditional and more innovative identification methods, including computer-aided taxonomy. Some ideas for applying information and communication technology (ICT) to constructing identification keysare discussed. The use of linked web pages is proposed as the most easily used and readily accessible method for Year 8 pupils (ages 12 – 13). It is suggested that there is more educational value in pupils then testing and evaluating each other's keys rather than simply using them and that to facilitate this, web-based keys can easily be exchanged via a network. It is concluded that this approach promotes a wide range of transferable ICT skills, but applies them in the context of a current problem facing real biologists, so illustrating how computer technology is assisting biodiversity research. 相似文献
37.
《Journal of biological education》2012,46(2):76-79
A dice game for teaching the relationship between water availability and water loss in plant growth 相似文献
38.
《Journal of biological education》2012,46(4):157-163
This study examined the effectiveness of worksheets while learning about biodiversity in a natural history museum. Despite the frequent use of worksheets by school classes during out-of-school activities, their effectiveness in enhancing knowledge acquisition has been addressed by relatively few empirical studies. 148 Austrian grammar school students aged eleven to fifteen took part in the pre- and post-test questionnaire study which included a one-hour learning phase with worksheets in the museum. Results indicate a high learning effect from pre- to post-test. Further analyses show that worksheets contributed to knowledge gain, but this contribution is similar to that afforded by prior knowledge. The design of the worksheet tasks was also important. A closed task setting required the students to look for clearly defined solutions. This led to greater knowledge gains than open worksheet tasks, where the spectrum of possible answers was wider. We concluded that worksheets can be used effectively for acquiring basic knowledge about biodiversity and suggest how to integrate the findings into the design of worksheets for out-of-school learning. 相似文献
39.
In order to better understand the relationship between reserve design and the species represented by such designs, we examined
the effectiveness of the Western Australian reserve system for conserving angiosperm diversity, and examined the characteristics
of those species conserved. We overlayed species distribution data for 14 plant lineages with the distribution of the reserve
system (8.5% of the State’s area) and identified the species that remained unprotected. We found that, depending upon the
method employed, between 174 (5.7%) and 570 (18.7%) of species were not included within the reserve system. Two main unprotected
regions were identified, one of which was also a centre of high diversity. Geographical range sizes of unprotected species
were six times smaller than those species that were protected, while species richness of small-ranged endemic species coincided
with general patterns of species richness. At the level of Western Australia’s bioregions we found that conservation effectiveness
was most dependent on characteristics of the reserve system rather than characteristics (size and positioning) of species
ranges. At this scale, the most effective way to conserve more species in Western Australia would be to conserve more land,
while conservation would be most successful in a uniformly dispersed reserve system. Our results highlight the fact that reserve
systems may take on two design approaches based on scale––at continental scales, reserves should be clustered around the hotspots
of endemic species, while within regions, an evenly distributed reserve system will most adequately sample species. 相似文献
40.
Paul Sillitoe 《Ethnos》2013,78(3):365-393
The animals of the Papua New Guinea highlands are relatively defenceless. People not only value their meat, hunters sharing catch with kin, but also formally transact several creatures in the all-important socio-political exchanges that characterise their social life. The local sedentary population is dense, yet it has not hunted species to extinction regardless of their value and vulnerability to predation. This paper seeks an answer in the context of socio-political exchange values that inform social status. It uses data from a survey of animal skull trophies displayed in a sample of houses in the Was valley of the Southern Highlands Province to investigate connections between hunting and social standing - exchange status, kin group affiliation and age - with a view to elucidating tacit conservation behaviour which agencies concerned to protect biodiversity might profitably consider given current participatory rhetoric. 相似文献