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Assessing sediment regime alteration of the upper Yangtze River

Journal Articles & Books
Dezembro, 2013

Employing the histogram matching approach, the sediment regime alteration of the upper Yangtze River was assessed and its possible causes and environmental influences were discussed. Daily sediment load and flow data from 1950 to 2008 were collected from Yichang hydrometric station. The annual sediment load series was segmented by heuristic segmentation algorithm in 1986 and 2003, and the multi-year mean values of the three phases were 5.28� ×� 10⁸, 3.89� ×� 10⁸ and 0.57� ×� 10⁸� t, respectively.

development of soil and water conservation policies and practices in five selected countries from 1960 to 2010

Journal Articles & Books
Dezembro, 2013
Indonésia
Bolívia
Tunísia
Estados Unidos
Espanha
Etiópia

Since the 1930s there has been worldwide concern about the effects and impacts of land degradation. After the problems experienced in the Dust Bowl in the USA, much attention was paid to soil and water conservation in both developed and developing countries. Initially Governments stimulated the establishment of physical control measures, such as terraces, check dams and reforestation. This was achieved through top-down regulations, and Forestry Departments were often in charge of the implementation.

Evaluating freshwater lens morphology affected by seawater intrusion using chemistry-resistivity integrated technique: a case study of two different land covers in Carey Island, Malaysia

Journal Articles & Books
Dezembro, 2013
Malásia

Freshwater lenses are vital to small island communities but are susceptible to seawater intrusion due to the physical changes in the shoreline land cover. The effect of seawater intrusion and irrigation water on a coastal unconfined aquifer beneath naturally preserved mangrove and deforested mangrove-barren belt was investigated in Carey Island. Analysis of the total dissolved solids (TDS) and earth resistivity (ER) using a geochemistry-electrical integrated technique gave a TDS–ER relationship capable of predicting freshwater lens morphology affected by sea-irrigation water.

Borders without barriers – Structural functionality and green infrastructure in the Austrian–Hungarian transboundary region of Lake Neusiedl

Journal Articles & Books
Dezembro, 2013

Many ongoing processes in today's landscapes impact our environment considerably. Thus, it is enormously important to gather information on qualitative characteristics of our landscapes in order to effectively counteract the negative developments. Structural functionality as proxy for the assessment of habitat quality and species patterns has already proven potential to successfully describe ecological values.

Mountain vegetation change quantification using surface landscape metrics in Lancang watershed, China

Journal Articles & Books
Dezembro, 2013
China

Land cover and vegetation change are among the most important aspects of environmental change. Vegetation change can be quantified by landscape pattern indices (LPI). Landscape indices are routinely calculated using planar land use/land cover (LU/LC) maps, obtained by the projection of a non-flat landscape surface into a two-dimensional Cartesian space. Especially in mountainous areas, quantification on planar maps can lead to underestimation of vegetation and land cover changes. Hoechstetter et al.

Impacts of edge density of field patches on plant species richness and community turnover among margin habitats in agricultural landscapes

Journal Articles & Books
Dezembro, 2013
Finlândia

In intensive agricultural environments, arable field margins are important habitats as reservoirs of various beneficial wild species. Many studies of species diversity in field margins have focused on the local habitat level. However, relationships between the network of the margin habitats and species diversity are less studied. Edge density index of field patches is a class-level landscape metric used as one measure of habitat network. This study focused on edge density index and its impacts on plant species richness and community turnover among the margins in agricultural landscapes.

Comparison between reconstructions of global anthropogenic land cover change over past two millennia

Journal Articles & Books
Dezembro, 2013
Suíça
Alemanha

Three global datasets, the History Database of the Global Environment (HYDE), Kaplan and Krumhardt (KK) and Pongratz of reconstructed anthropogenic land cover change (ALCC) were introduced and compared in this paper. The HYDE dataset was reconstructed by Goldewijk and his colleagues at the National Institute of Public Health and the Environment in Netherland, covering the past 12 000 years. The KK dataset was reconstructed by Kaplan and his colleagues, the Soil-Vegetation-Atmosphere Research Group at the Institute of Environmental Engineering in Switzerland, covering the past 8000 years.

Scale and ecological dependence of ecosystem services evaluation: Spatial extension and economic value of freshwater ecosystems in Italy

Journal Articles & Books
Dezembro, 2013
Itália

Using land cover datasets derived from satellite imagery as a proxy for ecosystem services (ES) mapping and evaluation generates a series of technical problems mainly related to the resolution at which spatial data are acquired. Small sized and highly fragmented ecosystems such as wetlands, streams and rivers are particularly underestimated when coarse resolution land cover datasets are used.

importance of accurate visibility parameterization during atmospheric correction: impact on boreal forest classification

Journal Articles & Books
Dezembro, 2013

Observation of the Earth's surface from spaceborne platforms is complicated by the various layers of the Earth's atmosphere that reflect, scatter, and attenuate electromagnetic radiation passing through them, thus influencing (upward or downward) the signal strength recorded at the sensor relative to the true quantity of radiance reflected from the observed surfaces. The magnitude and spatial distribution of atmospheric effects is non-stationary and will vary due to numerous factors.

Ground reference data error and the mis-estimation of the area of land cover change as a function of its abundance

Journal Articles & Books
Dezembro, 2013

Area estimation is a common application of remote sensing especially in relation to studies of land cover change. The use of an imperfect, nongold-standard, reference is shown to be a source of substantial error in estimates of change area. The relationships between the accuracy of land cover classifications, both real and perceived, together with area of change are explored over the full range of change abundance. The magnitude of mis-estimation varies with the abundance of change and the quality of the data sets used but may be large.

MNDISI: a multi-source composition index for impervious surface area estimation at the individual city scale

Journal Articles & Books
Dezembro, 2013

Impervious surface is a key indicator for monitoring urban land cover changes and human-environment interaction. Although the normalized difference impervious surface index (NDISI) has shown the potential to extract impervious surface areas (ISA) from multi-spectral imagery, it may lack robustness due to the spectral heterogeneity within urban impervious materials and confusion between other land covers. In this letter, a multi-source composition index is proposed to overcome the limitations of the original method.

Landscape pattern and sustainability of a 1300-year-old agricultural landscape in subtropical mountain areas, Southwestern China

Journal Articles & Books
Dezembro, 2013

The Hani terrace landscape located in the mountainous areas of Southwestern China has a history of 1300 years and is a classic example of human–environment harmony. This study investigates the spatial distribution and pattern characteristics of land cover in the landscape using geographical information system and remote-sensing techniques. With the synthetic consideration of both physical and cultural factors, the ecological stability of the landscape was discussed.