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The basin of the Służewiecki Stream, hydrologically uncontrolled, is urbanised, but it has a mosaic-like character, consisting of urban and agricultural land use. This is shown by the graph of the basin and its subcatchments that takes into account the changes of the runoff coefficient in its subcatchments. The land cover changes in 1993–2002 and the forecast for the years until 2012, together with the calculated rainfall hyetograph are input elements to the rainfall-runoff model. The isochrone method with the Kirpich equation constitute the transforming function, and the runoff hyetographs are the output elements from the system. The paper presents also practical problems occurring in the implementation of the recommendations of the local spatial plan as well as consequences resulting from disregarding the recommendations.
Land use/cover change (LUCC) is one of the main factors that influence the terrestrial carbon (C) and nitrogen (N) cycle. We examined the effects of land use/cover change on topsoil C, N, and microbial biomass C, N (MBC, MBN) and their relationship with other soil properties in the middle of Heihe river basin along a land use change gradient of 100-year farmland, 27-year farmland, 33-year pine forest, 28-year poplar forest, and 21-year shrubland, as well as native desert from which all the above cultivated systems are converted. Results revealed that land use conversion from native desert to the above cultivated ecosystems not only changed the basic eco-hydrological factors of the soil, such as improving the soil moisture and field capacity, decreasing the pH and salinity, but also altered the nutrient factors, such as improving the concentrations of soil organic C (SOC), total N (TN), MBC, MBN, NO₃⁻ -N and NH₄⁺ -N,. With the increase of cultivated years, land use conversion had an increasing impact on the C and N sequestration and soil nutrients stabilization.
In recent years, brown bear Ursus arctos populations in Iran have experienced a clear trend of reduction and the species is now officially listed as threatened under provincial legislation. Anthropogenic habitat alteration and increasing human access to previously remote landscapes are potential source of stress for this species in Iran. Therefore, land cover changes in the Chelcheli protected area were mapped for 1991–2013 using time sequential Landsat TM and ETM at 30 meters resolution. Moreover, Maximum entropy (MaxEnt) modeling was used to investigate habitat selection of brown bear. The results showed that suitable patches overlapped with forest areas (Hyrcanian forest) and rivers. Our results also indicate that the brown bear habitat suitability is negatively influenced by human disturbance (e.g., roads, settlements). Increased human disturbance in brown bear habitat in recent decades may cause bears to avoid the disturbed areas. Therefore, the management plans should focus on reducing the human infrastructures around brown bear habitat. A suggestion is to place the core secure areas for brown bear inside the suitable habitat close to rivers where the human access is restricted. Promoting awareness of biodiversity conservation among tourism should also be one of the major focuses of management plans.
Land cover change in any ecosystem vary in space and time. The study analyzed spatialtemporal land cover change to predict forest degradation pressure points in Eastern Mau Forest Reserve. The study objectives were to determine types and amount of spatial-temporal land cover change; land cover change drivers and; forest resources use sustainability. The study used mixed sample survey design involving purposive sampling of spatial data and cluster sampling of forest resource use data. Primary data included ground control points, field validation data and forest resource use data. Secondary data included Landsat imagery, forest and administration boundaries and settlements data. Analysis was done for 1986-2014 period using Remote Sensing and Geographical Information System. The analysis techniques used included object based image segmentation and classification, accuracy assessment and land cover change detection. Land cover types in Eastern Mau Forest consisted of indigenous forest, shrubland, grassland, plantation forest, cultivated fields, bare ground and built-up area. The analysis results depicted that cultivated fields coverage increased from 1% to 47%. Indigenous and plantation forests decreased from 43% to 36% and 34% to 7% respectively. Grassland and shrubland decreased from 16% to 8% and 6% to 2% respectively. Bare ground and built up area had a change of less than 1% each. Causes of pressure that lead to forest degradation included crop cultivation, settlement construction, livestock grazing, charcoal burning, firewood collection, logging, bee keeping and medicinal herbs extraction. Land cover change was more on the eastern side than on the western side. Indigenous and plantation forests were likely to disappear if cropland and built up area expansions were to remain unchecked. The study recommendations were: resettlement activities be eliminated in the Eastern Mau Forest; excision of forest land for crop cultivation should be discouraged; and scientific research should be carried out on sustainable plantation forest activities.
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