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101.
Implications of Land Use/Land Cover Change in the Buffer Zone of a National Park in the Tropical Andes 总被引:2,自引:0,他引:2
The impacts of land use and land cover (LULC) change in buffer zones surrounding protected ecological reserves have important
implications for the management and conservation of these protected areas. This study examines the spatial and temporal patterns
of LULC change along the boundary of Rio Abiseo National Park in the Northern Peruvian Andes. Landscape change within four
ecological zones was evaluated based on trends expected to occur between 1987 and 2001. Landsat TM and ETM imagery were used
to produce LULC classification maps for both years using a hybrid supervised/unsupervised approach. LULC changes were measured
using landscape metrics and from-to change maps created by post-classification change detection. Contrary to expectations,
tropical upper wet montane forest increased despite being threatened by human-induced fires and cattle grazing of the highland
grasslands inside the park. Within the park’s buffer zone, tropical moist forest remnants were fragmented into more numerous
and smaller patches between 1987 and 2001; this was in part due to conversion into agricultural land. The methods used in
this study provide an effective way to monitor LULC change detection and support the management of protected areas and their
surrounding environments. 相似文献
102.
介绍了哈密名城大气质量状况及特征,作了初步趋势分析.认为哈密地区大气主要污染物为降尘,然而大气环境质量近期发展不会严重恶化. 相似文献
103.
Evaluation of the European Space Agency Climate Change Initiative Soil Moisture Product over China Using Variance Reduction Factor
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Xiaoji Shen Ru An Jonathan Arthur Quaye‐Ballard Ling Zhang Zhe Wang 《Journal of the American Water Resources Association》2016,52(6):1524-1535
In this study, we evaluated the European Space Agency Climate Change Initiative soil moisture product v02.1 (ESA CCI SM v02.1) using in situ observations collected at 547 stations in China from 1991 to 2013. A conventional validation was first conducted, and the triple collocation errors of ESA CCI SM and the European Centre for Medium Range Weather Forecasting reanalysis data were approximately 0.053 and 0.050 m3/m3, respectively. To obtain more reliable validation results, the average soil moisture of the in situ observations per ESA CCI SM pixel was also used as the validation sites. Variance reduction factor (VRF) was adopted to quantify the accuracy of the soil moisture validation sites, and the average VRF was estimated at 4.88%. The validation results were enhanced by excluding validation sites with VRF errors greater than 5% from the statistical analysis. Although the ESA CCI SM underestimated the in situ observations with a Bias of 0.05 m3/m3, a moderately high correlation coefficient of 0.44 and a relatively small unbiased root‐mean‐square difference of 0.05 m3/m3 were observed. This study provides information on the utilization of ESA CCI SM for ecological protection, climate change, and hydrological forecasting. It also suggests the adoption of VRF for future error corrections of satellite‐based products. 相似文献
104.
105.
Modeling Change-Pattern-Value Dynamics on Land Use: An Integrated GIS and Artificial Neural Networks Approach 总被引:6,自引:0,他引:6
The use of spatial methods to detect and characterize changes in land use has been attracting increasing attention from researchers.
The objectives of this article were to formulate the dynamics of land use on the temporal and spatial dimensions from the
perspectives of the Change-Pattern-Value (CPV) and driving mechanism, based on multitemporal remote sensing data and socioeconomic
data. The Artificial Neural Networks were used to identify the factors driving changes in land use. The Pearl River Delta
Region of southeast China, which was experiencing rapid economic growth and widespread land conversion, has been selected
as the study region. The results show that from 1985 to 2000 in the study region (1) the most prominent characteristics of
change in land use were the expansion of the urban land at the expense of farmland, forests, and grasslands, (2) the land-use
pattern was being optimized during this period, (3) in an analysis of value, built-up land can yield a return of more than
30 times that of farmland, water area, and forests lands, and (4) rapid economic development, growth in population, and the
development of an infrastructure were major driving factors behind ecological land loss and the nonecological land expansion. 相似文献
106.
在与灾害进行斗争的长期过程中,人类逐步形成了关于灾害防治的指导思想,其中既有正确的、科学的成分.也有错误的、不合理的成分。本文依据灾害本身的性质与规律,从灾害与自然生态──社会经济系统的相互关系原理出发,分析并重新认识当代社会人类进行灾害防治工作的指导思想.以图确立正确的灾害防治指导思想.为减灾防灾工作顺利而有效的展开奠定基础。 相似文献
107.
This study describes the deforestation impact from three settlements, 5 de Junio, El Tigre, and 30 de Agosto, near the Madidi National Park in Bolivia. First deforestation rates along the road that connects the settlements and then deforestation within each settlement are examined. Landsat Thematic Mapper (TM) imagery from 1987, 1997, and 2000 were used to measure the deforestation. Face-to-face interviews were also used to collect detailed social and land-use information. Road-building and farming have been the major causes of deforestation in this region. The TM measurements indicate a high increase in the deforestation rate along the road in the area of study. The results also show a rapidly escalating deforestation rate in 5 de Junio, a potential high future deforestation rate in El Tigre, and a gradual deforestation increase in 30 de Agosto. The information provided by the settlers about clearing was compared with the imagery analysis. Generally, the settlers estimates were lower than the deforestation as derived from the imagery. 相似文献
108.
通过分析徐州市近几年的大气PM10监测数据和气象条件,研究了大气PM10质量浓度的时间变化规律及气象因素的影响,结果表明:PM10质量浓度年变化呈"冬重夏轻"的规律;在大气污染源数量和污染物排放量相对稳定的情况下,风和降水是影响大气颗粒物污染程度的主要气象因子,PM10浓度随温度的升高而降低,随气压的增强而减少。 相似文献
109.
大气中甲磺酸粒子的来源及其对环境的影响 总被引:2,自引:0,他引:2
讨论了大气中甲磺酸粒子的来源,分析了甲磺酸粒子的自然循环及其对酸雨形成和气候变化的影响。 相似文献
110.