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141.
Prescribed fires are a common nature conservation practice. They are executed by several parties with limited coordination among them, and little consideration for wildfire occurrences and habitat requirements of fire-dependent species. Here, we gathered data on prescribed fires and wildfires in Sweden during 2011–2015 to (i) evaluate the importance and spatial extent of prescribed fires compared to wildfires and (ii) illustrate how a database can be used as a management tool for prescribed fires. We found that on average only 0.006% (prescribed 65%, wildfires 35%) of the Swedish forest burns per year, with 58% of the prescribed fires occurring on clearcuts. Also, both wildfires and prescribed fires seem to be important for the survival of fire-dependent species. A national fire database would simplify coordination and make planning and evaluation of prescribed fires more efficient. We propose an adaptive management strategy to improve the outcome of prescribed fires. 相似文献
142.
Lauric Thiault Paul Marshall Stefan Gelcich Antoine Collin Frédérique Chlous Joachim Claudet 《Conservation biology》2018,32(2):447-456
An overarching challenge of natural resource management and biodiversity conservation is that relationships between people and nature are difficult to integrate into tools that can effectively guide decision making. Social–ecological vulnerability offers a valuable framework for identifying and understanding important social–ecological linkages, and the implications of dependencies and other feedback loops in the system. Unfortunately, its implementation at local scales has hitherto been limited due at least in part to the lack of operational tools for spatial representation of social–ecological vulnerability. We developed a method to map social–ecological vulnerability based on information on human–nature dependencies and ecosystem services at local scales. We applied our method to the small‐scale fishery of Moorea, French Polynesia, by combining spatially explicit indicators of exposure, sensitivity, and adaptive capacity of both the resource (i.e., vulnerability of reef fish assemblages to fishing) and resource users (i.e., vulnerability of fishing households to the loss of fishing opportunity). Our results revealed that both social and ecological vulnerabilities varied considerably through space and highlighted areas where sources of vulnerability were high for both social and ecological subsystems (i.e., social–ecological vulnerability hotspots) and thus of high priority for management intervention. Our approach can be used to inform decisions about where biodiversity conservation strategies are likely to be more effective and how social impacts from policy decisions can be minimized. It provides a new perspective on human–nature linkages that can help guide sustainability management at local scales; delivers insights distinct from those provided by emphasis on a single vulnerability component (e.g., exposure); and demonstrates the feasibility and value of operationalizing the social–ecological vulnerability framework for policy, planning, and participatory management decisions. 相似文献
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Trevor McIntyre Horst Bornemann Joachim Plötz Cheryl A. Tosh Marthán N. Bester 《Marine Biology》2011,158(9):2125-2139
The at-sea behaviour of marine top predators provides valuable insights into the distribution of prey species and strategies
used by predators to exploit patchily distributed resources. We describe the water column usage and dive strategies of female
southern elephant seals from Marion Island tracked between 2004 and 2008. Dives representing increases in forage effort were
identified using a method that combines dive type analyses and the calculation of relative amounts of time that animals spend
in the bottom phases of dives. Results from this analysis indicate that female elephant seals from Marion Island tend to display
lower levels of forage effort closer to the island and display intensive opportunistic forage bouts that occur at a minimum
distance of approximately 215 km from the island. Females from Marion Island dived deeper and for longer periods of time,
compared to females from other populations. Most animals displayed positive diel vertical migration, evidently foraging pelagically
on vertically migrating prey. A few animals displayed periods of reverse (negative) diel vertical migration, however, diving
to deeper depths at night, compared to daytime. This behaviour is difficult to explain and prey species targeted during such
periods unknown. Our results illustrate plasticity in foraging behaviour of southern elephant seals, as well as inter-population
differences in forage strategies. 相似文献
146.
Michael Neumann Joachim Baumeister Matthias Liess Ralf Schulz 《Environmental Sciences Europe》2003,15(3):152-156
The development and the evaluation of a biological indicator system for pesticide pollution in streams are presented. For small headwater streams with an agricultural catchment area, the expert system LIMPACT estimates the pesticide contamination according to the four classes of Not Detected, Low, Moderate and High contamination without any specification of the chemical agents. The input parameters are the abundance data of benthic macroinvertebrate taxa within four time frames in a year (March/April; May/June; July/August; September/October) and 9 basic water-quality and morphological parameters. The heuristic knowledge base was developed with the shell-kit D3 and contains diagnostic rules with scores to either establish or de-establish a contamination class. We differentiate between positive indicator taxa, which indicate contamination by high abundance values and positive abundance dynamics, and negative indicator taxa, a high abundance of which rules out contamination and indicates an uncontaminated site. We analysed 39 taxa and found 13 positive and 24 negative indicators. The database is comprised of 157 investigations per stream and year. For the evaluation of LIMPACT, we used the same cases. The correct diagnosis for the 157 investigations per stream and year is established by LIMPACT in 66.7 to 85.5% of the cases, with better results for uncontaminated sites. In most of the remaining cases no diagnosis is established instead of an incorrect one. 相似文献
147.
Dagmar Laschka Thomas Striebel Joachim Daub Markus Nachtwey 《Environmental Sciences Europe》1996,8(3):124-129
Using platinum based catalytic converters, platinum is emitted with the exhaust gases and deposited on the roads, and in their vicinity (sewage treatment plants, rivers), which increases the platinum concentrations in aquatic eco-systems. To evaluate the platinum discharge from roads, the platinum concentration was measured in rainwater from a road with a traffic fre quency of 16,000 automobiles per day. The platinum content of the samples varies strongly dependent upon the previous dry period, and the intensity and duration of the rainfall. Platinum was measured in 18 run-off samples from various rainfall events. The maximum platinum concentrations showed values up to 1.1. μg/l. The median value was 15 ng/l. Analysis of a sample from one rainfall events shows that platinum has a well defined firstflush effect, similar to that of particular bound lead and copper. The good correlation between platinum and coarse suspended matter, coarse particular lead and copper indicates that platinum in road run-offs is frequently found to be particular bound. Under the assumption that the road has been completely washed off, the platinum deposition can be estimated to be 14 ng/(m2d). 相似文献
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Joachim Gerlach 《Die Naturwissenschaften》1988,75(8):393-398