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Object-oriented classification of land use/cover using digital aerial orthophotography

Journal Articles & Books
Diciembre, 2012

In automatic/semiautomatic mapping of land use/cover using very high resolution remote-sensing imagery, the major challenge is that a single class of land use contains ground targets with varied spectral values, textures, geometries and spatial features. Here we present an object-oriented strategy for automatic/semiautomatic classifications of land use/cover using very high resolution remote-sensing data. The strategy consists of character detecting, object positioning and coarse classification, then refining the classification result step by step.

Process analysis in the coastal zone of Bénin through remote sensing and socio-economic surveys

Journal Articles & Books
Diciembre, 2012
Benin

Migration and population growth lead in coastal zones, especially in developing countries like Benin in Western Africa, to extreme land use pressure, causing ecological as well as land cover and land use changes, socio-economic modifications, and conflicts of interest and generational conflicts. To detect those fast-moving processes area-wide remains almost impossible in developing countries due to the lack of official statistics, often restricted remote sensing data, and limited financial resources.

Urban lakes in a developing nation: Drivers, states and impacts of water quality and quantity in Dhaka, Bangladesh

Journal Articles & Books
Diciembre, 2012
Bangladesh

This study examined pollution and shrinkage of urban lakes in the rapidly urbanizing city of Dhaka, Bangladesh. A mixed‐method approach was employed, nested within the European Environmental Agency Drivers, Pressure, States, Impacts, Responses Framework and Environmental Systems Analysis tools (as stakeholder and functions analysis methodologies). A variety of stakeholders and policymakers were first interviewed, being asked to participate in an exercise identifying their perceptions of the greatest challenges facing urban lakes in Dhaka.

Legacy of human-induced C erosion and burial on soil–atmosphere C exchange

Journal Articles & Books
Diciembre, 2012

Carbon exchange associated with accelerated erosion following land cover change is an important component of the global C cycle. In current assessments, however, this component is not accounted for. Here, we integrate the effects of accelerated C erosion across point, hillslope, and catchment scale for the 780-km ² Dijle River catchment over the period 4000 B.C. to A.D. 2000 to demonstrate that accelerated erosion results in a net C sink.

Validation of the collection 5 MODIS FPAR product in a heterogeneous agricultural landscape in arid Uzbekistan using multitemporal RapidEye imagery

Journal Articles & Books
Diciembre, 2012
Uzbekistán

The fraction of photosynthetically active radiation (FPAR) absorbed by a vegetation canopy is an important variable for global vegetation modelling and is operationally available from data of the Terra Moderate Resolution Imaging Spectroradiometer (MODIS) satellite sensor starting from the year 2000. Product validation is ongoing and important for constant product improvement, but few studies have investigated the specific accuracy of MODIS FPAR using in situ measurements and none have focused on agricultural areas.

Multi-temporal land-cover classification and change analysis with conditional probability networks: the case of Lesvos Island (Greece)

Journal Articles & Books
Diciembre, 2012
Grecia

This study uses a series of Landsat images to map the main land-cover types on the Mediterranean island of Lesvos, Greece. We compare a single-year maximum likelihood classification (MLC) with a multi-temporal maximum likelihood classification (MTMLC) approach, with time-series class labels modelled using a first-order hidden Markov model comprising continuous and discrete variables. A rigorous validation scheme shows statistically significant higher accuracy figures for the multi-temporal approach.

Mapping and monitoring riparian vegetation distribution, structure and composition with regression tree models and post-classification change metrics

Journal Articles & Books
Diciembre, 2012

Riparian systems have become increasingly susceptible to both natural and human disturbances as cumulative pressures from changing land use and climate alter the hydrological regimes. This article introduces a landscape dynamics monitoring protocol that incorporates riparian structural classes into the land-cover classification scheme and examines riparian change within the context of surrounding land-cover change.

Field_SWAT: A tool for mapping SWAT output to field boundaries

Journal Articles & Books
Diciembre, 2012

The Soil and Water Assessment Tool (SWAT) hydrological/water quality model divides a watershed into hydrological response units (HRUs) based on unique land cover, soil type, and slope. HRUs are a set of discontinuous land masses that are spatially located in the watershed but their responses are not tied to any particular field. Field_SWAT, a simple graphical user interface (GUI)-driven tool, was developed to map SWAT simulations from the HRU layer to a user-defined field boundaries layer.

Using modeled runoff to study DOC dynamics in stream and river flow: A case study of an urban watershed southeast of Boston, Massachusetts

Journal Articles & Books
Diciembre, 2012

The origin, function, and fate of dissolved organic carbon (DOC) in stream flow are not well-understood. This study explores the environmental factors controlling the spatial and temporal variation of DOC in terrestrial ecosystems of a watershed southeast of Boston, Massachusetts. Our hypothesis is that environmental factors: stream flow, land cover type, vegetation density, and drainage area are significant in estimating DOC export from an urban watershed.

hydrologic consequences of land cover change in central Argentina

Journal Articles & Books
Diciembre, 2012
Argentina
América del Sur

Vegetation exerts a strong control on water balance and key hydrological variables like evapotranspiration, water yield or even the flooded area may result severely affected by vegetation changes. Particularly, transitions between tree- and herbaceous-dominated covers, which are taking place at increasing rates in South America, may have the greatest impact on the water balance.

Development and validation of two fish-based indices of biotic integrity for assessing perennial coolwater streams in Wisconsin, USA

Journal Articles & Books
Diciembre, 2012
Estados Unidos de América
América Septentrional

Perennial coolwater streams (maximum daily mean water temperature 20.7–24.6°C; 90th percentile annual exceedence flow≥0.0283m³/s) are common in the Laurentian Great Lakes region of North America, including the state of Wisconsin, but they lack specific and effective bioassessment tools.

Multi-year black carbon emissions from cropland burning in the Russian Federation

Journal Articles & Books
Diciembre, 2012
Rusia
Europa oriental

Cropland fires are an important source of black carbon (BC) emissions. Previous research has suggested that springtime cropland burning in Eastern Europe, more specifically Russia, is a main contributor of BC in the Arctic atmosphere, acting as a short-lived climate forcer strongly influencing snow-ice albedo and radiation transmission.