Anthropogenic Disturbance and Biodiversity of Marine Benthic Communities in Antarctica: A Regional Comparison
Anthropogenic Disturbance and Biodiversity of Marine Benthic Communities in Antarctica: A Regional Comparison
复制标题
南极洲海洋底栖群落的人为干扰和生物多样性：区域比较
作者：
J. Stark;Stacy Kim;J. Oliver
比较了位于不同地区的两个南极站对海洋沉积物大型动物群落的影响：位于罗斯海的麦克默多站；以及位于南极洲东部的一个更典型的小站——凯西站。群落结构和多样性沿人为干扰从严重污染到未污染的梯度进行了比较。我们研究了在比较不相关研究数据时存在的一些固有问题，如不同的采样方法、采样的时空尺度和分类的不确定性。这些问题产生了特定的偏差，在解释模式时要考虑到这些偏差。两区对照点群落差异很大，但均以甲壳类为主。群落对人为干扰（金属、油和污水污染沉积物）的响应也不同。在麦克默多，受干扰地区的甲壳类动物比例下降，多毛类占主导地位，而在凯西，甲壳类动物对干扰的反应增加，主要是通过增加片脚类动物。尽管社区的总体反应不同，但也有一些共同的因素。介形类、丘贝类和棘皮类对干扰均较为敏感。多毛纲、多毛纲和多毛纲是受干扰地点的标志。片足类、等足类和单足类动物在不同站点的响应不同。受干扰地点的生物多样性和分类独特性均显著降低。然而，影响的大小与污染程度无关，较小、污染较少的站Casey的生物多样性减少幅度更大。因此，污染程度低至中等的小站的影响可能与污染严重的大型站的影响一样大。区域范围广泛的环境影响可能对确定群落的组成及其对干扰的反应很重要，但也有一些关于反应的概括，将有助于未来对监测站的管理。
The impacts of two Antarctic stations in different regions, on marine sediment macrofaunal communities were compared: McMurdo, a very large station in the Ross Sea; and Casey, a more typical small station in East Antarctica. Community structure and diversity were compared along a gradient of anthropogenic disturbance from heavily contaminated to uncontaminated locations. We examined some of the inherent problems in comparing data from unrelated studies, such as different sampling methods, spatial and temporal scales of sampling and taxonomic uncertainty. These issues generated specific biases which were taken into account when interpreting patterns. Control sites in the two regions had very different communities but both were dominated by crustaceans. Community responses to anthropogenic disturbance (sediment contamination by metals, oils and sewage) were also different. At McMurdo the proportion of crustaceans decreased in disturbed areas and polychaetes became dominant, whereas at Casey, crustaceans increased in response to disturbance, largely through an increase in amphipods. Despite differing overall community responses there were some common elements. Ostracods, cumaceans and echinoderms were sensitive to disturbance in both regions. Capitellid, dorvelleid and orbiniid polychaetes were indicative of disturbed sites. Amphipods, isopods and tanaids had different responses at each station. Biodiversity and taxonomic distinctness were significantly lower at disturbed locations in both regions. The size of the impact, however, was not related to the level of contamination, with a larger reduction in biodiversity at Casey, the smaller, less polluted station. The impacts of small stations, with low to moderate levels of contamination, can thus be as great as those of large or heavily contaminated stations. Regional broad scale environmental influences may be important in determining the composition of communities and thus their response to disturbance, but there are some generalizations regarding responses which will aid future management of stations.