Investigating an aquatic system as a route of entry for multiple environmental contaminants into Kruger National Park, South Africa

克鲁格国家公园（KNP）是一个200万公顷的保护区，是联合国教科文组织世界遗产，居住着数百种哺乳动物物种（包括狮子，豹子，犀牛，大象和水牛）和鸟类物种（包括许多秃鹫，鹰和鹳物种），其中许多物种具有保护重要性。然而，虽然国家立法保护公园的陆地边界，但环境污染物可以通过一些河流进入，特别是奥利凡特河。奥利凡特河发源于高原地区，向东北偏北方向流动，流经肯尼亚国家警察，最终进入莫桑比克。沿着KNP以外的长度，污染源包括：煤炭和金属开采（添加酸性废水和重金属），灌溉农业地区（径流，含有农药和化肥），以及几个城镇和城市（添加未经处理的废水）。这些污染源和这个独特的保护区的共同位置，有利于探索生态系统的健康和动物生活在这些对比鲜明的景观，这已受到人为活动的影响。在2008年和2009年，零星从那时起，尼罗河鳄鱼和莫桑比克罗非鱼的死亡发生在沿着Olifants的一些网站。泛脂肪炎，一种脂肪组织的炎症性疾病，在两个物种中被确定为死亡原因。确切的原因尚未确定，但有人认为，河流系统中的有机和/或无机污染物耗尽了这些动物体内的自由氧自由基清除剂，降低了它们代谢膳食脂肪酸的能力，导致泛脂肪炎。拟议的研究包括评估沉积物、水和无脊椎动物中的有机和无机污染物水平，在KNP内外的Olifants河流域沿着地点监测鱼类和鳄鱼的情况，以及鱼类和鳄鱼的健康。这将有助于评估污染物在多个营养级的分布和生物利用度，以及它们对动物健康的潜在影响。

Kruger National Park (KNP) is a 2 million hectare protected area, and a UNESCO World Heritage Site, inhabited by hundreds of mammalian species (including lions, leopards, rhinos, elephants and buffalos) and avian species (including numerous vulture, eagle and stork species), with many species of conservation importance. However, while national legislation protect the terrestrial boundaries of the park, environmental pollutants can enter by a number of rivers, particularly the Olifants River. The Olifants River begins in the Highveld region, flowing north-north-east, through KNP, and ultimately enters Mozambique. Along its length outside KNP, contaminant sources include: coal and metal mining (adding acid wastewater and heavy metals), areas of irrigated agriculture (with runoff, containing pesticides and fertilisers), and several towns and cities (adding untreated wastewater). The co-location of these sources of contamination, and this unique conservation area, facilitates a study exploring the health of the ecosystem and the animals living in these contrasting landscapes, which have been variably influenced by anthropogenic activities.In 2008 and 2009, and sporadically since then, dieoffs of Nile crocodiles and Mozambique tilapia occurred at a number of sites along the Olifants. Pansteatitis, an inflammatory condition of fat tissue, was identified in both species as the cause of death. A definitive cause has not been determined, but it has been suggested that organic and/or inorganic contaminants in the river system deplete free oxygen radical scavengers in these animals, reducing their ability to metabolise dietary fatty acids, resulting in pansteatitis.The proposed study involves assessing levels of organic and inorganic contaminants in sediment, water and invertebrates, fish and crocodiles at sites along the Olifants River system within and outside KNP, and health of the fish and crocodiles. This will enable assessment of the distribution and bioavailability of contaminants throughout multiple trophic levels, and their potential impact on animal health.