Xiao Rui, Jiang Diwei, Christakos George, Fei Xufeng, Wu Jiaping
Institute of Islands and Coastal Ecosystems, Zhejiang University, Zhoushan, China.
School of Remote Sensing and Information Engineering, Wuhan University, Wuhan, China.
PLoS One. 2016 Nov 10;11(11):e0166224. doi: 10.1371/journal.pone.0166224. eCollection 2016.
Soil sealing (loss of soil resources due to extensive land covering for the purpose of house building, road construction etc.) and subsequent soil landscape pattern changes constitute typical environmental problems in many places worldwide. Previous studies concentrated on soil sealing in urbanized regions, whereas rural areas have not been given sufficient attention. Accordingly, this paper studies soil landscape pattern dynamics (i.e., landscape pattern changes in response to rural anthropogenic activities) in the Tiaoxi watershed (Zhejiang province, eastern China), in which surface sealing is by far the predominant component of human forcing with respect to environmental change. A novel approach of quantifying the impacts of rural anthropogenic activities on soil resources is presented. Specifically, quantitative relationships were derived between five soil landscape pattern metrics (patch density, edge density, shape index, Shannon's diversity index and aggregation index) and three rural anthropogenic activity indicators (anthropogenic activity intensity, distance to towns, and distance to roads) at two landscape block scales (3 and 5 km) between 1985 and 2010. The results showed that the Tiaoxi watershed experienced extensive rural settlement expansion and high rates of soil sealing. Soil landscapes became more fragmented, more irregular, more isolated, and less diverse. Relationships between soil landscape pattern changes and rural anthropogenic activities differed with the scale (spatial and temporal) and variable considered. In particular, the anthropogenic activity intensity was found to be the most important indicator explaining social development intensity, whereas the other two proximity indicators had a significant impact at certain temporal interval. In combination with scale effects, spatial dependency (correlation) was shown to play a key role that should be carefully taken into consideration in any relevant environmental study. Overall, the findings of this work suggest that soil sealing can be a critical human forcing issue with considerable consequences deserving serious attention by the experts, the public and the government alike.
土壤封闭（由于建房、修路等大规模土地覆盖导致土壤资源流失）以及随之而来的土壤景观格局变化是全球许多地方典型的环境问题。以往的研究主要集中在城市化地区的土壤封闭，而农村地区尚未得到足够的关注。因此，本文研究了苕溪流域（中国东部浙江省）的土壤景观格局动态（即响应农村人为活动的景观格局变化），在该流域，就环境变化而言，地表封闭是人类活动影响的主要组成部分。本文提出了一种量化农村人为活动对土壤资源影响的新方法。具体而言，推导了1985年至2010年间两个景观斑块尺度（3公里和5公里）下五个土壤景观格局指标（斑块密度、边缘密度、形状指数、香农多样性指数和聚集度指数）与三个农村人为活动指标（人为活动强度、到城镇的距离和到道路的距离）之间的定量关系。结果表明，苕溪流域经历了广泛的农村聚落扩张和高比例的土壤封闭。土壤景观变得更加破碎、更加不规则、更加孤立且多样性降低。土壤景观格局变化与农村人为活动之间的关系因所考虑的尺度（空间和时间）及变量而异。特别是，人为活动强度被发现是解释社会发展强度的最重要指标，而其他两个邻近指标在特定时间间隔内有显著影响。结合尺度效应，空间依赖性（相关性）被证明起着关键作用，在任何相关环境研究中都应予以仔细考虑。总体而言，这项工作的结果表明，土壤封闭可能是一个关键的人类活动影响问题，其后果相当严重，值得专家、公众和政府 alike 的认真关注。 （注：原文中“alike”未准确翻译，这里保留原文是因为不太明确其确切想表达的中文含义，根据语境推测可能是“等等”之类的意思，但不确定，故保留英文。）
