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Mean shift-based clustering of remotely sensed data with agricultural and land-cover applications

Journal Articles & Books
Dezembro, 2013

The mean shift (MS) algorithm is based on a statistical approach to the clustering problem. Specifically, the method is a variant of density estimation. We revisit in this article the MS paradigm and its use for clustering of remotely sensed images. Specifically, we investigate further the classification accuracy of remotely sensed images as a function of various MS parameters, such as the variant used, kernel type, dimensionality, kernel bandwidth, etc.

SWAT plant growth modification for improved modeling of perennial vegetation in the tropics

Journal Articles & Books
Dezembro, 2013

The Soil and Water Assessment Tool (SWAT) has been used for assessing the impact of land cover and land management changes on water resources for a wide range of scales and environmental conditions across the globe. However, originally designed for temperate regions, SWAT must be critically examined for its appropriate use in tropical watersheds. One major concern is the simulation of perennial tropical vegetation due to the absence of dormancy.

Identifying bobcat Lynx rufus kill sites using a global positioning system

Journal Articles & Books
Dezembro, 2013
Estados Unidos

The role of predation in ecological systems has received considerable attention in scientific literature and is one of the most important, yet least understood aspects of carnivore ecology. Knowledge of factors that improve our ability to detect predation events using animal telemetry data could be used to develop strategies to reduce time and resources required to obtain reliable kill estimates.

Nest survival of wild turkeys Meleagris gallopavo silvestris in a mixed-use landscape: influences at nest-site and patch scales

Journal Articles & Books
Dezembro, 2013

Nest survival is a critical factor affecting avian demographics, and can be influenced by nesting chronology, fine scale nest-site selection and broad-scale landscape characteristics. We modeled the relative influences of nest age, temporal variation in nest success and habitat-related covariates at two spatial scales (nest-site and patch scale) on daily nest survival during incubation for eastern wild turkeys Meleagris gallopavo silvestris in a mixed-use landscape. Daily survival rate of turkey nests during incubation increased as percent understory cover (vegetation

high-resolution GIS null model of potential forest expansion following land use changes in Norway

Journal Articles & Books
Dezembro, 2013
Noruega

During recent decades, forests have expanded into new areas throughout the whole of Norway. The processes explained as causing the forest expansion have focused mainly on climate or land use changes. To enable a spatially explicit separation of the effects following these two main drivers behind forest expansion, the authors set out to model the potential for natural forest regeneration following land use abandonment, given the present climatic conditions.

Spatial assessment of ecosystem goods and services in complex production landscapes: A case study from south-eastern Australia

Journal Articles & Books
Dezembro, 2013
Austrália

Many production landscapes are complex human-environment systems operating at various spatio-temporal scales and provide a variety of ecosystem goods and services (EGS) vital to human well-being. EGS change over space and time as a result of changing patterns of land use or changes in the composition and structure of different vegetation types. Spatio-temporal assessment of EGS can provide valuable information on the consequences of changing land use and land cover for EGS and helps to deal with this complexity.

Using self-organizing maps to investigate environmental factors regulating colony size and breeding success of the White Stork (Ciconia ciconia)

Journal Articles & Books
Dezembro, 2013
Argélia

We studied variations in the size of breeding colonies and in breeding performance of White Storks Ciconia ciconia in 2006–2008 in north-east Algeria. Each colony site was characterized using 12 environmental variables describing the physical environment, land-cover categories, and human activities, and by three demographic parameters: the number of breeding pairs, the number of pairs with chicks, and the number of fledged chicks per pair.

Groundwater recharge and exploitative potential zone mapping using GIS and GOD techniques

Journal Articles & Books
Dezembro, 2013
Taiwan

Two-thirds of the total area of Taiwan is mountainous terrain, which is the main groundwater recharge source of the plains region. This study assesses groundwater recharge and exploitative potential zone in the central division of the mountain areas of Taiwan (the middle reaches of the Jhuoshuei River Basin). Basic information from remote sensing and a satellite phantom is collected to set up the basic data maps using elevation, Formosa-II images, the Normalized Difference Vegetation Index, drainage distribution, slope, aspect ratio, lineament distribution, and land cover.

procedure to obtain a refined European land use/cover map

Journal Articles & Books
Dezembro, 2013
Europa

Available land use/cover maps differ in their spatial extent and in their thematic, spatial, and temporal resolutions. Due to the costs of producing such maps, there is usually a trade-off between spatial extent and resolution. The only European-wide, consistent, and multi-temporal land use/cover dataset available is the CORINE Land Cover (CLC) map. Despite the value and usefulness of CLC, its minimum mapping unit (MMU) of 25 hectares considerably limits its applications at large scales of analysis.

hydro-climatological lake classification model and its evaluation using global data

Journal Articles & Books
Dezembro, 2013

For many of the world’s lakes, particularly those in remote regions, an assessment of the basin’s sensitivity to climate change is limited by the availability of appropriate hydrologic data. A regional steady-state lake water balance model was developed that uses simple, yet easily estimated or obtained, data to generate an aridity index (potential evapotranspiration to precipitation ratio) to predict changes in lake basin area to lake surface area ratio, a non-dimensional lake-basin property that can be easily obtained from digital maps.

Finer resolution observation and monitoring of global land cover: first mapping results with Landsat TM and ETM+ data

Journal Articles & Books
Dezembro, 2013
Groenlândia
Estados Unidos
Antártida

We have produced the first 30 m resolution global land-cover maps using Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) data. We have classified over 6600 scenes of Landsat TM data after 2006, and over 2300 scenes of Landsat TM and ETM+ data before 2006, all selected from the green season. These images cover most of the world's land surface except Antarctica and Greenland. Most of these images came from the United States Geological Survey in level L1T (orthorectified).

Land-use and land-cover change and its environmental implications in a tropical highland watershed, Ethiopia

Journal Articles & Books
Dezembro, 2013
Etiópia

This study analysed long-term land-use and land-cover change (LUCC) in a highland watershed covering an area of about 154 km² in the Blue Nile basin of Ethiopia. Two sets of panchromatic aerial photographs (1957 and 1982) and a Landsat TM image (2001) were the main input data from which three land-use and land-cover maps were produced by employing geographical information systems/remote sensing techniques. These data were complemented by some socio-economic data that were generated by using household survey, key-informant interview and group discussion methods.