کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10505027 946848 2013 17 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The climate-population nexus in the East African Horn: Emerging degradation trends in rangeland and pastoral livelihood zones
ترجمه فارسی عنوان
ناسازگاری آب و هوا در شاخ آفریقای شرقی: روند تشدید در مناطق زراعی و صیادی
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم محیط زیست علوم زیست محیطی (عمومی)
چکیده انگلیسی
Increasing climate variability and extreme weather conditions along with declining trends in both rainfall and temperature represent major risk factors affecting agricultural production and food security in many regions of the world. The rangelands of Ethiopia, Kenya, and Somalia in the East African Horn remain one of the world's most food insecure regions, yet have substantially increasing human populations predominantly dependent on pastoralist and agro-pastoralist livelihoods. We identify regions where substantial rainfall decrease between two periods interrupted by the 1998 El Nino event (1981-2012) in the East African Horn is coupled with human population density increases. Vegetation in this region is characterized by a variable mosaic of land covers, generally dominated by grasslands necessary for agro-pastoralism, interspersed by woody vegetation. Recent assessments indicate that vegetation degradation is occurring, adversely impacting fragile ecosystems and human livelihoods. Using AVHRR and MODIS vegetation products from 1981 to 2012, we observe changes in vegetation patterns and productivity over the last decade across the East African Horn. We observe vegetation browning trends in areas experiencing reduced main-growing season precipitation; these areas are also concurrently experiencing increasing population pressures. We also found that the drying precipitation patterns only partially statistically explain the vegetation browning trends, indicating that other factors such as population pressures and land use changes might be responsible for the observed declining vegetation condition. Furthermore, we show that the general vegetation browning trends persist even during years with normal rainfall conditions such as 2012, pointing to potential long-term degradation of rangelands on which approximately 10 million people depend. These findings may have implications for current and future regional food security monitoring and forecasting as well as for mitigation and adaptation strategies in a region where population is expected to continue increasing against a backdrop of drying climate trends and increased climatic variability.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Global Environmental Change - Volume 23, Issue 6, December 2013, Pages 1525-1541
نویسندگان
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