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Huber K - - 2010
The poultry red mite Dermanyssus gallinae is a major pest and widespread ectoparasite of laying hens and other domestic and wild birds. Under optimal conditions, D. gallinae can complete its lifecycle in less than 10 days, leading to rapid proliferation of populations in poultry systems. This paper focuses on developing ...
Costello Mark John - - 2010
Depth and topography directly and indirectly influence most ocean environmental conditions, including light penetration and photosynthesis, sedimentation, current movements and stratification, and thus temperature and oxygen gradients. These parameters are thus likely to influence species distribution patterns and productivity in the oceans. They may be considered the foundation for any ...
Poirier Magalie - - 2010
It has been hypothesized that the increase in temperature in this century could lead to an increase in frost damage to plant tissues. Several models have been proposed to describe the development of cold hardiness, but never taking into account extreme climatic and/or physiological events. Our results on walnut tree ...
Tominaga Koji - - 2010
The performance and prediction uncertainty (owing to parameter and structural uncertainties) of four dynamic watershed acidification models (MAGIC, PnET-BGC, SAFE, and VSD) were assessed by systematically applying them to data from the Hubbard Brook Experimental Forest (HBEF), New Hampshire, where long-term records of precipitation and stream chemistry were available. In ...
Drewry J J - - 2011
This paper investigates index models as a tool to estimate the risk of N and P source strengths and loss at the catchment scale. The index models assist managers in improving the focus of remediation actions that reduce nutrient delivery to waterbodies. N and P source risk factors (e.g. soil ...
Hook S E - - 2010
The advent of any new technology is typically met with great excitement. So it was a few years ago, when the combination of advances in sequencing technology and the development of microarray technology made measurements of global gene expression in ecologically relevant species possible. Many of the review papers published ...
Meirmans Patrick G - - 2011
Although F(ST) is widely used as a measure of population structure, it has been criticized recently because of its dependency on within-population diversity. This dependency can lead to difficulties in interpretation and in the comparison of estimates among species or among loci and has led to the development of two ...
Norby Richard J - - 2010
Stimulation of terrestrial plant production by rising CO(2) concentration is projected to reduce the airborne fraction of anthropogenic CO(2) emissions. Coupled climate-carbon cycle models are sensitive to this negative feedback on atmospheric CO(2), but model projections are uncertain because of the expectation that feedbacks through the nitrogen (N) cycle will ...
Olang Luke Omondi - - 2011
The spatio-temporal changes in the land cover states of the Nyando Basin were investigated for auxiliary hydrological impact assessment. The predominant land cover types whose conversions could influence the hydrological response of the region were selected. Six Landsat images for 1973, 1986, and 2000 were processed to discern the changes ...
Little L R - - 2011
Changes in the management of the fin fish fishery of the Great Barrier Reef motivated us to investigate the combined effects on economic returns and fish biomass of no-take areas and regulated total allowable catch allocated in the form of individual transferable quotas (such quotas apportion the total allowable catch ...
Borja Angel - - 2010
Through implementing environmental Directives, Europe has moved towards coordinated and integrated catchment-to-coast management, following the most novel legislation on ecosystem-based approaches worldwide. The novel joint synthesis of this direction reviewed here allows us to regard the Water Framework Directive (WFD) as a 'deconstructing structural approach' whereas the Marine Strategy Framework ...
Wang Xiaoyan - - 2011
The objective of this paper is to study the impact of the mesh size of the digital elevation model (DEM) on terrain attributes within an Annualized AGricultural NonPoint Source pollution (AnnAGNPS) Model simulation at watershed scale and provide a correction of slope gradient for low resolution DEMs. The effect of ...
Salamin Nicolas - - 2010
Climate change poses a serious threat to species persistence. Effective modelling of evolutionary responses to rapid climate change is therefore essential. In this review we examine recent advances in phylogenetic comparative methods, techniques normally used to study adaptation over long periods, which allow them to be applied to the study ...
Oukouomi Noutchie Suares Clovis - - 2010
A theoretical approach is used to investigate the quantitative and qualitative effects of the flocculation and break-up of aggregates of phytoplankton. The importance of these processes in the study of fish recruitment is discussed. Furthermore, results indicate that fragmentation and coagulation dynamics do not play a significant role in the ...
Melbinger Anna - - 2010
Existing theoretical models of evolution focus on the relative fitness advantages of different mutants in a population while the dynamic behavior of the population size is mostly left unconsidered. We present here a generic stochastic model which combines the growth dynamics of the population and its internal evolution. Our model ...
Phong Thai Khanh - - 2011
Monitoring studies revealed high concentrations of pesticides in the drainage canal of paddy fields. It is important to have a way to predict these concentrations in different management scenarios as an assessment tool. A simulation model for predicting the pesticide concentration in a paddy block (PCPF-B) was evaluated and then ...
Vospernik Sonja - - 2010
Height:diameter ratios are an important measure of stand stability. Because of the importance of height:diameter ratios for forest management, individual-tree growth models should correctly depict height:diameter ratios. In particular, (i) height:diameter ratios should not exceed that of very dense stands, (ii) height:diameter ratios should not fall below that of open-grown ...
Bruhn Dan - - 2011
To understand what governs the patterns of net ecosystem exchange of CO(2), an understanding of factors influencing the component fluxes, ecosystem respiration and gross primary production is needed. In the present paper, we introduce an alternative method for estimating daytime ecosystem respiration based on whole ecosystem fluxes from a linear ...
Ma Jing - - 2011
The Devils Lake Emergency Outlet Diversion conflict is systematically studied from a strategic viewpoint using the Graph Model for Conflict Resolution in order to obtain insights about the resolution of this nagging international dispute. By modelling the conflict for the situation existing as of July 2005, just before the project ...
Bailey Geoffrey N - - 2011
This paper examines the relationship between complex and tectonically active landscapes and patterns of human evolution. We show how active tectonics can produce dynamic landscapes with geomorphological and topographic features that may be critical to long-term patterns of hominin land use, but which are not typically addressed in landscape reconstructions ...
Bailey R M - - 2011
Understanding the behaviour of complex environmental systems, particularly as critical thresholds are approached, is vitally important in many contexts. Among these are the moisture-limited vegetation systems in semi-arid (SA) regions of the World, which support approximately 36 per cent of the human population, maintain considerable biodiversity and which are susceptible ...
Chou Wei-Chun - - 2010
Diarrhea is an important public health problem in Taiwan. Climatic changes and an increase in extreme weather events (extreme heat, drought or rainfalls) have been strongly linked to the incidence of diarrhea-associated disease. This study investigated and quantified the relationship between climate variations and diarrhea-associated morbidity in subtropical Taiwan. Specifically, ...
Ginelli Francesco - - 2010
We show that the collective properties of self-propelled particles aligning with their topological (Voronoi) neighbors are qualitatively different from those of usual models where metric interaction ranges are used. This relevance of metric-free interactions, shown in a minimal setting, indicate that realistic models for the cohesive motion of cells, bird ...
Forrest Jessica - - 2010
Phenology affects nearly all aspects of ecology and evolution. Virtually all biological phenomena-from individual physiology to interspecific relationships to global nutrient fluxes-have annual cycles and are influenced by the timing of abiotic events. Recent years have seen a surge of interest in this topic, as an increasing number of studies ...
Crevoisier Cyril - - 2010
Studies diverge substantially on the actual magnitude of the North American carbon budget. This is due to the lack of appropriate data and also stems from the difficulty to properly model all the details of the flux distribution and transport inside the region of interest. To sidestep these difficulties, we ...
Glenk Klaus - - 2011
This paper describes an approach to account for asymmetric preference formation in discrete choice models used for environmental valuation. The paper draws on data from a case study on preferences for environmental change resulting from a hypothetical rural development and conservation programme in Indonesia. Local knowledge on the current state ...
Lynch A J J - - 2011
There is no comprehensive system of describing threats and disturbances currently used in Australia, despite the widespread impacts of human activities on natural ecosystems. Yet a detailed categorization would facilitate the collation of threatening process information into information systems; enable standardized collection and availability of data; and enable comparative analyses ...
Felinger Attila - - 2011
A number of models in chromatography have analytical solutions in the Laplace or Fourier domain. Often, the moments of the Laplace domain solutions are calculated to characterize the peak shape. Nonlinear fitting in the Fourier domain can be performed to exploit the entire peak shape rather than the moments only. ...
Memon Junaid Alam - - 2011
This study examines the impact of an elaborated irrigation system on the natural resources and society in the deltaic part of the Indus River in Pakistan. Time series information was collected to analyze the ecological and natural resource dynamics, and their impacts on the structure and quality of the occupations ...
Lederhendler A - - 2010
A generalization of the ABC model, a one-dimensional model of a driven system of three particle species with local dynamics, is introduced, in which the model evolves under either (i) density-conserving or (ii) nonconserving dynamics. For equal average densities of the three species, both dynamical models are demonstrated to exhibit ...
Syed Tajdarul H - - 2010
Freshwater discharge from the continents is a key component of Earth's water cycle that sustains human life and ecosystem health. Surprisingly, owing to a number of socioeconomic and political obstacles, a comprehensive global river discharge observing system does not yet exist. Here we use 13 years (1994-2006) of satellite precipitation, ...
Sharma R - - 2010
The high variability in survival over the past three decades of north-west Pacific Chinook salmon Oncorhynchus tshawytscha is summarized for 24 stocks and analysed using hierarchical Bayesian models. Results from a simple model indicate that recruitment anomalies appear to be correlated in time and space. A simple model with a ...
Sadeghi Ravesh Mohammad Hassan - - 2011
Desertification, land degradation in arid, semi-arid, and dry sub-humid regions, is a global environmental problem. With respect to increasing importance of desertification and its complexity, the necessity of attention to the optimal de-desertification alternatives is essential. Therefore, this work presents an analytic hierarchy process (AHP) method to objectively select the ...
Presser Theresa S - - 2010
The main route of exposure for selenium (Se) is dietary, yet regulations lack biologically based protocols for evaluations of risk. We propose here an ecosystem-scale model that conceptualizes and quantifies the variables that determine how Se is processed from water through diet to predators. This approach uses biogeochemical and physiological ...
Gayle Peter - - 2010
Discovery Bay is one of nine sites around Jamaica's coastline, soon to gain the legislative protection of Fish Sanctuary (and Scientific Reserve) status. Cumulative natural and anthropogenic impacts drove the 1980's coral to algae phase shift. Discovery Bay CARICOMP data (1994 to 2007) showed an increase in coral cover from ...
Gericke Dirk - - 2010
According to the EU directive 91/414/EEC potential environmental concentrations of pesticides have to be assessed with environmental fate models. For the calculation of pesticide concentrations it is necessary to provide an application date which has to match the specific Biologische Bundesanstalt, Bundesamt, Chemische Industrie (BBCH) stage at which the pesticide ...
Dearden J C - - 2010
Bioconcentration factor (BCF) is an important step in the uptake of environmental pollutants in the food chain. It is expensive and time-consuming to measure, so predictive methods are of value. We have used an artificial neural network QSAR approach involving descriptors for hydrophobicity, hydrogen bonding and molecular topology, obtained from ...
Colombo A F - - 2010
After 500 years of exploitation and destruction, the Brazilian Atlantic Forest has been reduced to less the 8% of its original cover, and climate change may pose a new threat to the remnants of this biodiversity hotspot. In this study we used modelling techniques to determine present and future geographical ...
Fujita Yoshiko - - 2010
This study was a preliminary evaluation of ureolytically driven calcite precipitation and strontium coprecipitation for remediating (90)Sr contamination at the Hanford 100-N Area in Washington; in particular the approach is suitable for treating sorbed (90)Sr that could otherwise be a long-term source for groundwater contamination. Geochemical conditions at the site ...
Reynolds Travis William TW Daniel J. Evans School of Public Affairs, University of Washington, Seattle, WA 98195-3055, USA. - - 2010
In 1992, a mental-models-based survey in Pittsburgh, Pennsylvania, revealed that educated laypeople often conflated global climate change and stratospheric ozone depletion, and appeared relatively unaware of the role of anthropogenic carbon dioxide emissions in global warming. This study compares those survey results with 2009 data from a sample of similarly ...
Bennema S C - - 2011
Fasciola hepatica, a trematode parasite with a worldwide distribution, is the cause of important production losses in the dairy industry. Diagnosis is hampered by the fact that the infection is mostly subclinical. To increase awareness and develop regionally adapted control methods, knowledge on the spatial distribution of economically important infection ...
Baasch David M - - 2010
In recent years, elk have begun recolonizing areas east of the Rocky Mountains that are largely agro-forested ecosystems composed of privately owned land where management of elk is an increasing concern due to crop and forage depredation and interspecific disease transmission. We used a Geographic Information System, elk use locations ...
Zhang Yang - - 2011
On the basis of remote sensing and GIS techniques, the Landsat data obtained in 1987, 1996, and 2008 were used to examine coastline changes in the Modern Yellow River (MYR) delta in China. The coastal land lost and gained illustrations were derived, the rates of coastal change were estimated, and ...
Qi Honghai - - 2011
Land use planning is an important element of the integrated watershed management approach. It not only influences the environmental processes such as soil and stream bed erosion, sediment and nutrient concentrations in streams, quality of surface and ground waters in a watershed, but also affects social and economic development in ...
Dierssen Heidi M - - 2010
Phytoplankton biomass and productivity have been continuously monitored from ocean color satellites for over a decade. Yet, the most widely used empirical approach for estimating chlorophyll a (Chl) from satellites can be in error by a factor of 5 or more. Such variability is due to differences in absorption and ...
Omo-Irabor Omo O - - 2011
Mangroves are known for their global environmental and socioeconomic value. Despite their importance, mangrove like other ecosystems is now being threatened by natural and human-induced processes that damage them at alarming rates, thereby diminishing the limited number of existing mangrove vegetation. The development of a spatial vulnerability assessment model that ...
Helle Inari - - 2011
Maritime traffic poses a major threat to marine ecosystems in the form of oil spills. The Gulf of Finland, the easternmost part of the Baltic Sea, has witnessed a rapid increase in oil transportation during the last 15 years. Should a spill occur, the negative ecological impacts may be reduced ...
Majdalani Samer - - 2011
The identification of groundwater parameters in heterogeneous systems is a major challenge in groundwater modeling. Flexible parameterization methods are needed to assess the complexity of the spatial distributions of these parameters in real aquifers. In this article, we introduce an adaptative parameterization to identify the distribution of hydraulic conductivity within ...
Thomson Stuart N - - 2010
Theoretical analysis predicts that enhanced erosion related to late Cenozoic global cooling can act as a first-order influence on the internal dynamics of mountain building, leading to a reduction in orogen width and height. The strongest response is predicted in orogens dominated by highly efficient alpine glacial erosion, producing a ...
Poor Cara J - - 2010
The use of regression tree analysis is examined as a tool to evaluate hydrologic and land use factors that affect nitrate and chloride stream concentrations during low-flow conditions. Although this data mining technique has been used to assess a range of ecological parameters, it has not previously been used for ...
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