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991.
992.
In a recent perspective (Diversity and Distributions, 29, 39–50), ‘10 variables’ were proposed to measure vegetation structure from airborne laser scanning (ALS) for assessing species distributions and habitat suitability. We worry about this list because the variables predominantly represent variation in vegetation height, the vertical variability of vegetation biomass is insufficiently captured, and variables of vegetation cover are ill-defined or not ecosystem agnostic. We urge for a better defined, more comprehensive and more balanced list, and for assessing which information from ALS point clouds is truly essential to measure the major dimensions of 3D vegetation structure within and across ecosystems and animal habitats. We think that the currently proposed ‘list of 10 ALS metrics’ is premature and that researchers and stakeholders should be cautious in adopting this list. 相似文献
993.
Poverty and environmental degradation seem to be endemic in many of the former homeland territories of South Africa. The political legacy of Apartheid might have ceased, but the economic and environmental consequences thereof still have to be dealt with. In one interesting case such a poverty-stricken and environmentally degraded area (Bushbuckridge) lies adjacent to a world conservation icon, the Kruger National Park. Currently, however, the community of Bushbuckridge does not enjoy much benefit from this unique geographic location. On the contrary there seems to be increasing tension between the community in their quest for survival and the national park as a conservation enclave. This tension will not disappear automatically. The situation needs to be managed. It is proposed here that by broadening the conservation corridor through land restoration and by incorporating the Bushbuckridge communal land as an IUCN Category VI protected area (a protected area within which sustainable resource harvesting by communities is permitted) into the Kruger National Park and under the provision that the community remains the land owner, the conservation initiative could benefit the community as much as by a factor of four. For this to be successful a proper managerial and institutional system will have to be in place, including a system that will allow the trade in ecosystem goods and services. 相似文献
994.
Anthropogenic pressures put at jeopardy ecosystem services (ES) provided by natural habitats. Ecosystem Based Management (EBM) approaches can support policymakers dealing with physical, chemical, and biological stresses caused by high-risk water pollution (HRWP) and sudden-accidental pollution (SAP). The objective of this study is to evaluate how alarming HRWP pressures might become in fragile marine, coastal, estuarine, and freshwater socio-ecological systems (MCEF-SES) surrounded by heavily industrialized and urbanized areas. To this end a spatially explicit analysis, using the InVEST-Habitat Risk Assessment (InVEST-HRA) model in combination with expert judgement from researchers from various fields, is performed. An application is provided for the case of the Ria de Aveiro (RdA) coastal lagoon in Portugal. Results show high spatial variance of HRWP hazards across RdA, with one major multi-layer risk hotspot at the center of the research area and a second patch of multiple risk hotspots towards the North of RdA. Salines emerge as the most threatened habitat followed by Intertidal flats and Saltmarshes. The most significant water pollution risk sources contributing to Salines cumulative risk are Fossil fuel processing, storage and sale units, Industrial units, Aquaculture, and the Marinas. Industries involving dangerous substances in the region threaten primarily Watercourses. This study confirms the InVEST-HRA model in combination with expert judgement is a transparent and easily replicable approach to build ES-based knowledge about habitat risks threatening MCEF-SES in a Natura 2000 site heavily pressured by HRWP hazards. After further valuation analysis, pondering gains and losses from regional development and environmental protection, this knowledge can support the planning and management of coastal areas and the prioritization of pollution abatement interventions. In particular, by estimating the loss that HRWP causes in the value of ecosystem services, defining HRWP abatement policies, assessing the effectiveness, costs and benefits of those abatement policies and, ultimately, evaluating the results for the well-being of local communities through global efficiency analysis, cost-benefit analysis or cost-effectiveness analysis. Hence, it bridges the gap between an informed EBM and the development policies of fragile regions. 相似文献
995.
996.
Andreas Engelen Peter Convey Dominic A. Hodgson M. Roger Worland Sieglinde Ott 《Polar Biology》2008,31(12):1453-1460
Inland Antarctic nunataks typically have simple physically weathered soils and limited ecosystem complexity. In this paper
we present quantitative measurements of soil physical and chemical properties at one Antarctic nunatak. We measured pH, grain
size, field capacity, soil organic carbon, phosphate, nitrate, ammonium and the cations magnesium, calcium and potassium along
two transects. The data obtained indicated that very low levels of nutrients were present/available to biota, and that liquid
water was absent, at least from the surface depths of soil, except during periods of active snow melt. Consequently, biological
activity is severely limited. We conclude that, due to the climatic and microclimatic conditions at this location, the development
of biological communities and soils is maintained in an extremely simple but still apparently stable ‘quasi climax’ state.
Increased soil development and biological complexity can be expected if the contemporary rapid regional warming in the Antarctic
Peninsula region continues. 相似文献
997.
998.
The Tropical managed Forests Observatory: a research network addressing the future of tropical logged forests
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Plinio Sist Ervan Rutishauser Marielos Peña-Claros Alexander Shenkin Bruno Hérault Lilian Blanc Christopher Baraloto Fidèle Baya Fabrice Benedet Katia Emidio da Silva Laurent Descroix Joice Nunes Ferreira Sylvie Gourlet-Fleury Marcelino Carneiro Guedes Ismail Bin Harun Riina Jalonen Milton Kanashiro Haruni Krisnawati Mrigesh Kshatriya Philippa Lincoln Lucas Mazzei Vincent Medjibé Robert Nasi Marcus Vinicius N. d'Oliveira Luis C. de Oliveira Nicolas Picard Stephan Pietsch Michelle Pinard Hari Priyadi Francis. E. Putz Ken Rodney Vivien Rossi Anand Roopsind Ademir Roberto Ruschel Nur Hajar Zamah Shari Cintia Rodrigues de Souza Farida Herry Susanty Eleneide Doff Sotta Marisol Toledo Edson Vidal Thales A.P. West Verginia Wortel Toshihiro Yamada 《应用植被学》2015,18(1):171-174
While attention on logging in the tropics has been increasing, studies on the long-term effects of silviculture on forest dynamics and ecology remain scare and spatially limited. Indeed, most of our knowledge on tropical forests arises from studies carried out in undisturbed tropical forests. This bias is problematic given that logged and disturbed tropical forests are now covering a larger area than the so-called primary forests. A new network of permanent sample plots in logged forests, the Tropical managed Forests Observatory (TmFO), aims to fill this gap by providing unprecedented opportunities to examine long-term data on the resilience of logged tropical forests at regional and global scales. TmFO currently includes 24 experimental sites distributed across three tropical regions, with a total of 490 permanent plots and 921 ha of forest inventories. 相似文献
999.
To investigate the applicability of ecological engineering to pollution problems prevalent in present-day Central and Eastern Europe, a SCOPE-UNEP sponsored workshop was held in Estonia in November 1995. The workshop was undertaken specifically to obtain information from and to train planners, managers and scientists in the region. These ‘countries in transition' face, in many respects, unique environmental problems as a result of their recent domination by a centralized planning government system. Twenty workshop findings that resulted from workshop presentations and subsequent discussion are presented. Six papers published as part of this special issue of Ecological Engineering, and summarized here, deal with the general principles of mineland restoration, acidification effects and mitigation in Poland, reestablishment of riparian buffer strips in Estonia, recovery of forests in the Black Triangle of Czechoslovakia and Poland, restoration after 10 years near the Chernobyl nuclear plant accident in the Ukraine, and studies on remediation of contaminated soils in Belarus. 相似文献
1000.
《Indian pacing and electrophysiology journal》2021,21(6):412-415
Tricuspid annular PVCs constitute 8% of idiopathic PVCs and 5% of RV PVCs. Although a rare entity to encounter in routine clinical practice, it can be a prime culprit behind major arrhythmic burden in few individuals. Electroanatomic approach with sub tricuspid retrograde catheter technique can target those annular PVCs and decrease the arrhythmia burden to normal or near normal range. Although procedural approach for parahisian PVCs requires a close look to avoid injury to native conduction system, TA PVCs are a real challenge due to inherent catheter instability and contact issue in sub tricuspid retrograde approach. 相似文献