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Probabilistic uncertainty specification: Overview, elaboration techniques and their application to a mechanistic model of carbon flux

Journal Articles & Books
Diciembre, 2012

It is widely recognised that the appropriate representation for expert judgements of uncertainty is as a probability distribution for the unknown quantity of interest. However, formal elicitation of probability distributions is a non-trivial task. We provide an overview of this field, including an outline of the process of eliciting knowledge from experts in probabilistic form. We explore approaches to probabilistic uncertainty specification including direct elicitation and Bayesian analysis.

use of detailed biotope data for linking biodiversity with ecosystem services in Finland

Journal Articles & Books
Diciembre, 2012
Finlandia
Global

It has been widely accepted that ecosystem services (ESs) should be taken into account in natural resource management decisions. Hence, there is an increasing need for innovative quantification methods and tools to evaluate ESs on different landscape scales, and under varying land-use forms. Integrating biodiversity protection with the provision of ESs is a key element for sustainable land-use planning. Geographic Information Systems (GIS) and spatial analysis, together with various environmental data, provide a suitable foundation for ESs evaluations.

Can remote sensing estimate fine-scale quality indicators of natural habitats?

Journal Articles & Books
Diciembre, 2012

Efficient management and conservation of natural habitats requires a thorough knowledge and sustained monitoring of their ecological quality. In recent years, several methods have been developed to assess the local conservation status in the field. These typically combine estimates of coarse-scale indicators, such as tree and grass encroachments, with very fine-scale indicators that require precise fieldwork, such as the number of key species present. We first tested whether coarse-scale field characteristics can provide information on fine-scale indicators.

Solute geochemical mass-balances and mineral weathering rates in small watersheds II: Biomass nutrient uptake, more equations in more unknowns, and land use/land cover effects

Journal Articles & Books
Diciembre, 2012
Estados Unidos de América

Paired watersheds are used to develop a deciduous nutrient uptake stoichiometry. The watersheds are those of the House Rock Run and the Brubaker Run located in the Pennsylvania Appalachian Piedmont, USA. These two watersheds are nearly identical with respect to bedrock, regolith, climate, geomorphology, morphometry, baseflow hydrology, and type and successional stage of forest vegetation. They only differ by the percentage of deciduous forest cover, with House Rock Run having 59% and Brubaker Run having 76%.

Epistemic uncertainty in predicting shorebird biogeography affected by sea-level rise

Journal Articles & Books
Diciembre, 2012

Accurate spatio-temporal predictions of land-cover are fundamentally important for assessing geomorphological and ecological patterns and processes. This study quantifies the epistemic uncertainty in the species distribution modeling, which is generated by spatio-temporal gaps between the biogeographical data, model selection and model complexity. Epistemic uncertainty is generally given by the sum of subjective and objective uncertainty. The subjective uncertainty generated by the modeler-choice in the manipulation of the environmental variables was analyzed.

Impact Assessment of Watershed Programme Through Remote Sensing and Geographical Information System

Journal Articles & Books
Diciembre, 2012

Impact assessment of watershed development activity assumes greater importance in present day agriculture. Considering the ability of remote sensing technology in watershed monitoring and impact assessment, a study was carried out to investigate the Impact Assessment of Karnataka Watershed Development Project (DANIDA) in Koralahallihalla Sub watershed in Sindagi taluk of Bijapur district in Northern Karnataka using satellite data of two periods i.e., IRS 1 C, LISS-III data of 30 December, 1997 (pre-treatment) and IRS P6, LISS-III data of 17 December, 2004 (post-treatment).

Canada Warbler use of harvested stands following timber management in the southern portion of their range

Journal Articles & Books
Diciembre, 2012
Canadá

We evaluated Canada Warbler (Cardellina canadensis) responses to changes in habitat characteristics (landscape metrics, landcover, and microhabitat features) at multiple spatial scales resulting from timber harvests (clear-cut, heavy partial, and light partial) between 1996 and 2009. Relative abundance of Canada Warblers decreased over time on our West Virginia study area (Wildlife and Ecosystem Research Forest) and within the Appalachian Bird Conservation Region.

Quantifying changes in flooding and habitats in the Tonle Sap Lake (Cambodia) caused by water infrastructure development and climate change in the Mekong Basin

Journal Articles & Books
Diciembre, 2012
Camboya

The economic value of the Tonle Sap Lake Floodplain to Cambodia is arguably among the highest provided to a nation by a single ecosystem around the world. Nonetheless, the Mekong River Basin is changing rapidly due to accelerating water infrastructure development (hydropower, irrigation, flood control, and water supply) and climate change, bringing considerable modifications to the flood pulse of the Tonle Sap Lake in the foreseeable future.

Microbial enzyme stoichiometry and nutrient limitation in US streams and rivers

Journal Articles & Books
Diciembre, 2012
Estados Unidos de América

We analyzed water and sediment chemistry, catchment land cover, and microbial dehydrogenase (DHA) and extracellular enzymes activities (EEA) related to microbial C, N, P, and S acquisition in more than 2100 1st–10th order streams. The streams and their catchments represented gradients in water and sediment chemistry (C, N, P, S) and land cover (% forest, % wetland, % row crop agriculture) against which to compare biofilm and sediment DHA and EEA, and to estimate the extent of nutrient limitation in US streams and rivers.

Impacts of land use changes and synoptic forcing on the seasonal climate over the Pearl River Delta of China

Journal Articles & Books
Diciembre, 2012
China

In this study, the impact of the rapid rate of urbanization over the Pearl River Delta (PRD) region of China since the 1980s on its seasonal climate is investigated using the Weather Research and Forecasting Model. Two land-cover data are employed to simulate the urbanization effects on the regional climate in both summer (June and August) and winter (December and February) for 26 years from 1984 to 2009. Spatial and temporal features of the urbanization effect on temperature and precipitation are found to be different between summer and winter.

Impact of loess relief on land use mosaic in SE Poland

Journal Articles & Books
Diciembre, 2012

Land cover is one of the most changeable environment components in time and space. The type, intensity and spatial distribution of land use forms result directly from the actual and former character of agriculture. In this study, an attempt was made to assess the impact of loess relief on the spatial diversity of land use patch features. The research was carried out within three test areas covering a total of about 100km². The test areas are located within the loess areas of SE Poland. Spatial analyses were carried out using GIS software.

Spatio-temporal variability of streamflow in the Yellow River: possible causes and implications

Journal Articles & Books
Diciembre, 2012
China

The water shortage in the Yellow River, China, has been aggravated by rapid population growth and global climate changes. To identify the characteristics of streamflow change in the Yellow River, approximately 50 years of natural and observed streamflow data from 23 hydrological stations were examined. The Mann-Kendall and Pettitt tests were used to detect trends and abrupt change points.