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The importance of preserving both protected areas and their surrounding landscapes as one of the major conservation strategies
for tigers has received attention over recent decades. However, the mechanism of how land-use surrounding protected areas
affects the dynamics of tiger populations is poorly understood. We developed Panthera Population Persistence (PPP)—an individual-based
model—to investigate the potential mechanism of the Sumatran tiger population dynamics in a protected area and under different
land-use scenarios surrounding the reserve. We tested three main landscape compositions (single, combined and real land-uses
of Tesso-Nilo National Park and its surrounding area) on the probability of and time to extinction of the Sumatran tiger over
20 years in Central Sumatra. The model successfully explains the mechanisms behind the population response of tigers under
different habitat landscape compositions. Feeding and mating behaviours of tigers are key factors, which determined population
persistence in a heterogeneous landscape. All single land-use scenarios resulted in tiger extinction but had a different probability
of extinction within 20 years. If tropical forest was combined with other land-use types, the probability of extinction was
smaller. The presence of agroforesty and logging concessions adjacent to protected areas encouraged the survival of tiger
populations. However, with the real land-use scenario of Tesso-Nilo National Park, tigers could not survive for more than
10 years. Promoting the practice of agroforestry systems surrounding the park is probably the most reasonable way to steer
land-use surrounding the Tesso-Nilo National Park to support tiger conservation. 相似文献
405.
The oxyfuel process is one of the most promising options to capture CO2 from coal fired power plants. The combustion takes place in an atmosphere of almost pure oxygen, delivered from an air separation unit (ASU), and recirculated flue gas. This provides a flue gas containing 80–90 vol% CO2 on a dry basis. Impurities are caused by the purity of the oxygen from the ASU, the combustion process and air ingress. Via liquefaction a CO2 stream with purity in the range from 85 to 99.5 vol% can be separated and stored geologically. Impurities like O2, NOX, SOX, and CO may negatively influence the transport infrastructure or the geological storage site by causing geochemical reactions. Therefore the maximum acceptable concentrations of the impurities in the separated CO2 stream must be defined regarding the requirements from transportation and storage. The main objective of the research project COORAL therefore is to define the required CO2 purity for capture and storage. 相似文献
406.
Christopher William Woodall Michael C. Amacher William A. Bechtold John W. Coulston Sarah Jovan Charles H. Perry KaDonna C. Randolph Beth K. Schulz Gretchen C. Smith Borys Tkacz Susan Will-Wolf 《Environmental monitoring and assessment》2011,177(1-4):419-436
For two decades, the US Department of Agriculture, Forest Service, has been charged with implementing a nationwide field-based forest health monitoring effort. Given its extensive nature, the monitoring program has been gradually implemented across forest health indicators and inventoried states. Currently, the Forest Service??s Forest Inventory and Analysis program has initiated forest health inventories in all states, and most forest health indicators are being documented in terms of sampling protocols, data management structures, and estimation procedures. Field data from most sample years and indicators are available on-line with numerous analytical examples published both internally and externally. This investment in national forest health monitoring has begun to yield dividends by allowing evaluation of state/regional forest health issues (e.g., pollution and invasive pests) and contributing substantially to national/international reporting efforts (e.g., National Report on Sustainability and US EPA Annual Greenhouse Gas Estimates). With the emerging threat of climate change, full national implementation and remeasurement of a forest health inventory should allow for more robust assessment of forest communities that are undergoing unprecedented changes, aiding future land management and policy decisions. 相似文献
407.
This paper compares the capability of a first-order and a spherical diffusion model to describe and predict long-term sorption and desorption processes of chlortoluron in two soils. Chlortoluron sorption was investigated at different time scales utilizing one rate experiment (120 days) and two sorption/desorption experiments. Experimental periods for sorption and desorption were set to 1 day (five desorption steps) and 30 days (three desorption steps), respectively. Upon fitting, the two models satisfactorily described the whole set of data. The spherical diffusion model performed better than the first-order model. We then tested the predictive capability of the models by predicting 30-day sorption/desorption data using kinetic parameters fitted on 1-day sorption/desorption data only. While the spherical diffusion model was able to predict the 30-day data set, the first-order model failed completely. Fitting both models to subsets of the data corresponding to different experimental time scales revealed that the rate parameter as well as the Freundlich coefficient of the first-order model are strongly time-dependent--a property that is not shared by parameters of the spherical diffusion model. The apparent stability of the spherical diffusion model with regard to time dependency of its parameters indicates that sorptive uptake may be diffusion-controlled. This also explains the models greater predictive power across different time scales compared to the first-order model. Finally, we investigate the suitability of solute class specific log-linear relationships between the first-order rate parameter and the Freundlich coefficient presented by earlier researchers in the light of the time dependency observed for the parameters of the first-order model. 相似文献
408.
R Schulz 《Chemosphere》2001,45(4-5):543-551
Spray drift and edge-of-field runoff are regarded as important routes of nonpoint-source pesticide input into aquatic surface waters, with current regulatory risk assessment in Europe focussing largely on spray drift. However, the two routes of entry had rarely been compared directly in the same catchment. To this end, the concentrations and loads of the current-use insecticides azinphos-methyl (AZP) and endosulfan (END) were monitored in the Lourens River, South Africa downstream of a 400-ha fruit orchard area during normal farming practice. Spray drift-related peak pesticide levels in the tributaries were in the range of 95th-percentiles of standard drift values according to regulatory risk assessment procedures. Resulting concentrations in Lourens River water samples (n = 3) at a discharge of 0.28 m3/s were as high as 0.04 +/- 0.01 microg/l AZP and 0.07 +/- 0.02 microg/l END. Pesticide levels at the same site during runoff following 3 storm events varying in rainfall between 6.8 and 18.4 mm/d (discharge: 7.5-22.4 m3/s) were considerably higher: by factors between 6 and 37 for AZP (0.26-1.5 microg/l) and between 2 and 41 for END (0.13-2.9 microg/l). Levels of pesticides associated with suspended particles were increased during runoff only up to 1247 microg/kg AZP and 12082 microg/kg END. A possible reason for the relative importance of runoff is that runoff largely integrates potential pesticide input over both time and space, because the prerequisites for the occurrence of runoff in terms of application and plot characteristics as well as meteorological conditions are far less specific than for spray drift. A probability analysis based on pesticide application patterns and 10-yr rainfall data indicates that the frequencies of rainfall events > or = 10 and > or = 15 mm/d are 3.4 and 1.7 per spraying season, respectively. 相似文献
409.
Reduced take-off ability in robins (Erithacus rubecula) due to migratory fuel load 总被引:11,自引:0,他引:11
Lind Johan Fransson Thord Jakobsson Sven Kullberg Cecillia 《Behavioral ecology and sociobiology》1999,46(1):65-70
Recent studies have shown that large fuel loads in small birds impair flying ability. This is the first study to show how
migratory fuel load affects flying ability, such as velocity and height gained at take-off in a predator escape situation,
in a medium-distance migrant, and whether they adjust their take-off according to predator attack angle. First-year robins
(Erithacus rubecula) were subjected to simulated attacks from a model merlin (Falco columbarius), and take-off velocity and angle were analysed. Robins with a wing load of 0.19 g cm−2 took off at a 39% lower angle than robins with a wing load of 0.13 g cm−2, while velocity remained unaffected. The robins did not adjust their angle of ascent in accordance with the predator's angle
of attack. Since many predators rely on surprise attacks, a difference in flight ability due to varying fuel loads found in
migrating robins can be important for birds' chances of survival when actually attacked.
Received: 28 October 1998 / Received in revised form: 12 January 1999 / Accepted: 30 January 1999 相似文献
410.
Sven Ove Hansson 《Process Safety and Environmental Protection》2010,88(3):168-172
By inherent safety is meant that a hazard is eliminated rather than being managed by various add-on equipment and procedures. Practices of inherent safety have been developed in the chemical industry, and include for instance the substitution of hazardous substances by less hazardous ones. Inherently safer design strives to eliminate the possibility of major adverse events even when the probabilities of these events are small or cannot be meaningfully estimated. Considerations of security can be more easily incorporated into this approach than into most other branches of risk and safety analysis. Therefore, inherent safety has a great potential as a meeting-ground for the much-needed coordination of safety and security work. Its philosophical underpinnings are outlined, and proposals are made for more efficient promotion of its principles. 相似文献