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multi-modeling approach to evaluating climate and land use change impacts in a Great Lakes River Basin

Journal Articles & Books
December, 2010

River ecosystems are driven by linked physical, chemical, and biological subsystems, which operate over different temporal and spatial domains. This complexity increases uncertainty in ecological forecasts, and impedes preparation for the ecological consequences of climate change. We describe a recently developed “multi-modeling” system for ecological forecasting in a 7600 km² watershed in the North American Great Lakes Basin.

Soil panning by drive systems of agricultural machines

Policy Papers & Briefs
December, 2010
Belarus

The results of the field research studying the effects of aggregates with heavy payload machines on the soil are presented. The influence of maximum tire pressure on soil while changing the pressure in a wide range is analyzed. The main characteristics of the machines, such as total mass; running gear load level; tire air pressure; maximal pressure on soil; soil density and the dip of the machine's track are shown. The experiment has been made on different soil types. Changes of relative strain of loose and solid sandy clay are displayed.

Deforestación en ecosistemas templados de la precordillera andina del centro-sur de Chile

Journal Articles & Books
December, 2010
Chile

A multitemporal analysis to determine the land cover change was conduced in the pre-Andean range of Maule region of Chile. We used satellite imagery from the year 1989 and 2003 to analyze the likely causes of native forest change. In this period, there was a reduction in native forest area of 44% in the study area, which is equivalent to an annual forest loss rate of 4.1%. The native forest area is replaced by shrublands (29%) and exotic forest plantations (27%). A great proportion of current exotic forest plantations are established on lands that were native forest in 1989 (63%).

Size-dependent pattern of wildfire ignitions in Portugal: when do ignitions turn into big fires

Journal Articles & Books
December, 2010
Portugal

Not all wildfire ignitions result in burned areas of a similar size. The aim of this study was to explore whether there was a size-dependent pattern (in terms of resulting burned area) of fire ignitions in Portugal. For that purpose we characterised 71,618 fire ignitions occurring in the country in the period 2001-2003, in terms of population density in the local parish, land cover type and distance to roads. We then assigned each ignition into subsets of five classes according to the resulting burned area: >5 ha, >50 ha, >100 ha, >250 ha, >500 ha.

Time stability and variability of Electronically Scanned Thinned Array Radiometer soil moisture during Southern Great Plains hydrology experiments

Journal Articles & Books
December, 2010

Variability and time-stability analysis for field-scale (800 m) Electronically Scanned Thinned Array Radiometer soil moisture within a satellite scale footprint (~ 50 km) were quantified using observations from the Southern Great Plains Hydrology Experiment 1997 and 1999 (SGP97 and SGP99).

Timely identification of agricultural crops in the Temelin NPP vicinity using satellite data in the event of radiation contamination

Policy Papers & Briefs
December, 2010
Czech Republic

This study established the possibility of rapid evaluation of land cover structure and situation using as an example the Temelin Nuclear Power Plant (Czech Republic) emergency zone. The composition, surface representation and spatial distribution of crop species in the area of interest were assessed on the basis of satellite data analysis (Landsat 5 TM). The supervised classification method of Landsat data yielded 92% accuracy of classification into the land cover classes.

Multistate modeling of habitat dynamics: factors affecting Florida scrub transition probabilities

Journal Articles & Books
December, 2010

Many ecosystems are influenced by disturbances that create specific successional states and habitat structures that species need to persist. Estimating transition probabilities between habitat states and modeling the factors that influence such transitions have many applications for investigating and managing disturbance‐prone ecosystems. We identify the correspondence between multistate capture–recapture models and Markov models of habitat dynamics.

Towards the use of ecological heterogeneity to design reserve networks: a case study from Dadia National Park, Greece

Journal Articles & Books
December, 2010
Greece

In this paper, we present a novel approach for using ecological heterogeneity in reserve design. We measured five ecological heterogeneity indices (EHI) and we used a database of six biological groups (woody plants, orchids, orthopterans, aquatic and terrestrial herpetofauna and passerine birds) across 30 sites in a Mediterranean reserve (Greece). We found that all the five EHI were significantly related to the overall species richness and to the species richness of woody plants and birds.

Climate change‐linked range expansion of Nathusius' pipistrelle bat, Pipistrellus nathusii (Keyserling & Blasius, 1839)

Journal Articles & Books
December, 2010
United Kingdom
Europe

Aim To examine the effect of climate change on the occurrence and distribution of Pipistrellus nathusii (Nathusius' pipistrelle) in the United Kingdom (UK). Location We modelled habitat and climatic associations of P. nathusii in the UK and applied this model to the species' historical range in continental Europe. Methods A binomial logistic regression model was constructed relating the occurrence of P. nathusii to climate and habitat characteristics using historical species occurrence records (1940-2006) and CORINE land cover data.

Wheeled robot for rural environment

Conference Papers & Reports
December, 2010
Latvia
Spain

In this paper solutions are proposed to improve the performance of a wheeled robot for rural environment. These solutions can be used for a wheeled mobile robot that moves upon curved surfaces, surfaces with irregularities and small coefficient of static friction between the wheels and the surface. The design and control of the robot are based on a new concept of a wheeled mobile robot, which can work in two different modes.

Savanna fire regimes assessment with MODIS fire data: Their relationship to land cover and plant species distribution in western Burkina Faso (West Africa)

Journal Articles & Books
December, 2010
Burkina Faso

The West African savannas are subject to changes in fire regimes related to land use intensification, which may infer significant biological modifications. We investigated the efficiency of MODIS fire products to account for the variability of fire regimes in relation to changes in land cover and savanna vegetation. The specificity and complementarities of both MODIS active fire (MOD14A2 and MYD14A2) and burnt area (MCD45A1) products were assessed in order to characterize fire regimes and to relate them with land cover.

Standardized FAO-LCCS land cover mapping in heterogeneous tree savannas of West Africa

Journal Articles & Books
December, 2010
Burkina Faso
Western Africa

Land cover is a key parameter in geosciences and a linkage between many aspects of the physical and human environments. Savannas belong to the biomes where land cover mapping with remote sensing faces the most difficulties and several studies already addressed the challenging definition of savanna land cover classes. With the aim to standardize ongoing mapping activities, the Land Cover Classification System (LCCS) was initiated in 1993.