摘要:Acacia of the western Butana plain of the Sudan has undergone severe deterioration during last decades as demonstrated by a survey carried out in 2005. The majority of Acacia is non-succulent which are differing spatially, by soil type and in cover; frequency; abundance and density. There was a climax for Acacia in the study area prior to 1850, while its deterioration took place through four successive stages. The ecosystem carrying capacity of the study area was adequate to support Acacia up to the year 1900 when human exploitation of Acacia was balancing with its growth up to that year. Ecological disequilibrium started directly after 1970 and manifested by declining ecosystem carrying capacity and thus deterioration of Acacia. This deterioration of Acacia appears to be linked with the reduction in average annual rainfall. This paper demonstrates that, though important, this factor is not the sole, and may not even be the main factor involved. Government investment policy and associated population activities including, for example agricultural expansion which contributed by 40% in Acacia deterioration and fuel wood by 30%, are shown to have great significance, and cast doubt to any belief that a return to higher rainfall levels would reverse the current deterioration processes.
关键词:Acacia;deterioration;Butana;rainfall fluctuation;Sahel zone;rainfed agriculture human factors;community education