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471.
Modified Whittaker plots as an assessment and monitoring tool for vegetation in a lowland tropical rainforest 总被引:3,自引:0,他引:3
Campbell P Comiskey J Alonso A Dallmeier F Nuñez P Beltran H Baldeon S Nauray W de la Colina R Acurio L Udvardy S 《Environmental monitoring and assessment》2002,76(1):19-41
Resource exploitation in lowland tropical forests is increasingand causing loss of biodiversity. Effective evaluation and management of the impacts of development on tropical forests requires appropriate assessment and monitoring tools. We proposethe use of 0.1-ha multi-scale, modified Whittaker plots (MWPs) to assess and monitor vegetation in lowland tropical rainforests.We established MWPs at 4 sites to: (1) describe and comparecomposition and structure of the sites using MWPs, (2) compare these results to those of 1-ha permanent vegetation plots (BDPs),and (3) evaluate the ability of MWPs to detect changes in populations (statistical power). We recorded more than 400 species at each site. Species composition among the sites was distinctive, while mean abundance and basal area was similar. Comparisons between MWPs and BDPs show that they record similarspecies composition and abundance and that both perform equallywell at detecting rare species. However, MWPs tend to record morespecies, and power analysis studies show that MWPs were more effective at detecting changes in the mean number of species of trees 10 cm in diameter at breast height (dbh) and in herbaceous plants. Ten MWPs were sufficient to detect a change of 11% in the mean number of herb species, and they were able to detect a 14% change in the mean number of species of trees 10 cm dbh. The value of MWPs for assessment and monitoringis discussed, along with recommendations for improving the sampling design to increase power. 相似文献
472.
Francisco Taveira Pinto 《Journal of Coastal Conservation》2004,10(1):147-157
The practice of coastal zone management in Portugal is very recent. Key issues and considerations about natural shoreline
dynamics, main policy instruments, and lessons learned from the EU Demonstration Programmes on Integrated Coastal Zone Management
in Portugal will be outlined in this paper in an attempt to understand how the practice of ICZM and its prospects are. Coastal
zone management problems and their associated side effects, as well as national and international evolution patterns will
be drawn. Some means of achieving better coastal zone management practices and ways of addressing some of its forefront issues
are also identified. Special attention will go to erosion problems. The pressure induced by urban development and economic
activities on coastal areas is increasing. Poor sediment availability combined with years of neglected management and over-exploitation
of resources have had a negative impact, and there are many areas showing evidence of coastal erosion. There is a need to
improve policies and instruments of coastal planning and management. Coastal zone management plans are being developed for
the nine sectors of the continental Portuguese coast, providing a full analysis of coastal systems and a delimitation of uses
in relation to the carrying capacity of the shoreline. 相似文献
473.
Conservation of endangered species requires comprehensive understanding of their distribution and habitat requirements, in order to implement better management strategies. Unfortunately, this understanding is often difficult to gather at the short term required by rapidly declining populations of many rare vertebrates. We present a spatial habitat modeling approach that integrates a molecular technique for species detection with landscape information to assess habitat requirements of a critically endangered mammalian carnivore, the Iberian lynx (Lynx pardinus), in a poorly known population in Spain. We formulated a set of model hypotheses for habitat selection at the spatial scale of home ranges, based on previous information on lynx requirements of space, vegetation, and prey. To obtain the required data for model selection, we designed a sampling protocol based on surveys of feces and their molecular analysis for species identification. After comparing candidate models, we selected a parsimonious one that allowed (1) reliable assessment of lynx habitat requirements at the scale of home ranges, (2) prediction of lynx distribution and potential population size, and (3) identification of landscape management priorities for habitat conservation. This model predicted that the species was more likely to occur in landscapes with a higher percentage of rocky areas and higher cover of bushes typical of mature mediterranean shrubland mosaics. Its accuracy for discriminating lynx presence was approximately 85%, indicating high predictive performance. Mapping model predictions showed that only 16% of the studied areas constitute potential habitat for lynx, even though the region is dominated by large extents of well-preserved native vegetation with low human interference. Habitat was mostly clumped in two nearby patches connected by vegetation adequate for lynx dispersal and had a capacity for 28-62 potential breeding territories. The lynx population in Sierra Morena is probably the largest persisting today, but it is still critically small for optimism about its long-term persistence. Model results suggest habitat conservation and restoration actions needed for preserving the species, including reconciliation of hunting management with preservation of mature shrubland over large areas (particularly in rocky landscapes). The approach presented here can be applied to many other species for which the ecological information needed to develop sound habitat conservation strategies is lacking. 相似文献
474.
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476.
Janaína Campos Senra Carlos Tadashi Yoshizaki Giovana Farina Doro Rodrigo Ruano Maria Augusta Bento Cicaroni Gibelli Agatha Sacramento Rodrigues Vera Hermina Kalika Koch Vera Lúcia Jornada Krebs Marcelo Zugaib Rossana Pulcineli Vieira Francisco Lisandra Stein Bernardes 《黑龙江环境通报》2020,40(11):1408-1417
477.
478.
Birds are the most diverse vertebrate group in Chile, characterized by low species turnover at the country-size scale (high alpha but low beta diversities), resembling an island biota. We tested whether this low differentiation is valid at a local scale, among six forest habitat types. We detected 25 bird species; avifauna composition was significantly different among habitat types, with five species accounting for 60 % of the dissimilarity. We found a higher level of bird assemblage differentiation across habitats at the local scale than has been found at the country-size scale. Such differentiation might be attributed to structural differences among habitats. 相似文献
479.
Defalque Cristiane Maria Marins Fernando Augusto Silva da Silva Aneirson Francisco Rodríguez Elen Yanina Aguirre 《Journal of Material Cycles and Waste Management》2021,23(1):55-76
Journal of Material Cycles and Waste Management - A discussion is currently under way in the literature on the sustainable benefits of recycling material, particularly paper, which has high global... 相似文献
480.
The sequential extraction procedures described by Tessier et al., McGrath and Cegarra, and Gimeno-García et al. were compared
to investigate trace element (As, Cr, Cu, Pb, and Zn) partitioning patterns and extraction efficiency in three contaminated
soils from Mediterranean regions of Spain. Soils were selected from Onda (Castellón) (S1), Aznalcóllar (Sevilla) (S2), and
Silla (Valencia) (S3). S1 was a soil contaminated with Pb and Zn after dumping of wastes from the manufacture of ceramic tiles,
S2 was polluted accidentally with a highly acid and As-concentrated sludge from mining activities, and S3 was a soil with
a high Cr content from tannery sludge disposal. Trace element distribution in the soils—soluble, exchangeable, organically
bound, precipitated with carbonates, bound to iron and manganese oxides, and precipitated with sulfides fractions—varied significantly
according to the extraction procedure used. In addition, different extraction efficiencies were found for the three sequential
extraction procedures compared. Finally, the trace elements studied showed different and specific distribution patterns between
the various soil fractions examined. 相似文献