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Extended over 85.4 km2 with more than 2.5 million date palm trees, Al-Ahsa oasis in the eastern part of Saudi Arabia is the largest oasis in Arabian Peninsula and probably in the world. The oasis became a World Heritage site in 2018 and has also been part of the UNESCO Creative Cities Network since 2015. The urban expansion and the transition from farms being the main source of income to farms being lifestyle properties, has changed the farm management practices. However, farm ownership continues to be a very strong feature of Al Ahsa communities, with livestock raising integrated with the cultivation of date palms. In oasis farms, date palms products are used as animal feed while animal manure is used as date palm fertilizer. Unfortunately, the huge stockpiles of date palm fronds and burning within the oasis suggest that the waste management practices may not be environmentally sustainable. Therefore, this study was carried out to assess the impact of livestock raising on the oasis farms soil conditions. The methodology followed in the study involved site visits to farms, reviewing related reports and articles on farm management practices and water quality. Key findings of the study indicated that livestock raising on date palm farms has significantly increased over the last 4 decades. Since the 1970’s, the number of farms housing cows has increased from 34% to 100%, and the number with hybrid poultry farms has increased from 4% to 50%. Results indicated that the reuse of all cow and chicken sand / manure mixes, generated on oasis farms, as fertilizer would increase the nitrogen, phosphorus and potassium by 17, 32 and 8 times respectively, over the recommended levels. Moreover, further application of manure from intensive chicken and dairy enterprises located near the oasis as fertilizer is not sustainable and lead to several environmental impacts. To reduce these impacts, the study recommends the development of a composting facility for the date palm fronds which may provide a sustainable alternative waste management system for the green and livestock wastes. In addition, farmers could benefit from both a high volume, low cost mulch that could be produced from date palm pruning, and a low volume, higher cost composted soil conditioner that could be produced from low nutrient shredded green waste and high nutrient livestock waste. Reuse of these recycled products within the urban centers could improve water use efficiency and protect landscape plantings from sand storms, and could replace imported soil conditioners. These alternative waste management strategies will reduce the nutrient pressure on the oasis by redirecting organic products processed from farm wastes for beneficial reuse in urban centers. |
