IDENTIFYING SENSITIVE INDICES IN THE RESPONSE OF AQUATIC BIOTA TO LANDSCAPE PATTERN CHANGES: A CASE STUDY OF THE TAIZI RIVER BASIN IN NORTH CHINA

Abstract

It is widely accepted that riverine ecosystems are influenced by the landscape pattern changes of their corresponding watersheds, but few studies have identified the most sensitive and nonsensitive biotic indices, the most influential landscape metrics and the relationship between aquatic biota and landscape patterns. To address this problem, Taizi river basin of Northeast China is taken as a case study, in which GIS technology and landscape ecology method are adopted. The study is performed at both the basin scale (entire drainage area upstream from certain sample point) and the riparian scale (a certain width buffer on each side of sample point extending the length of drainage network) to direct future landscape pattern design at the corresponding scales. The results show that at the basin scale, the species richness of benthic macroinvertebrate (B-S) and the fish index of biotic integrity (F-IBI) are the most sensitive biotic indices to landscape metrics, whereas the species richness of phytoplankton (P-S), the Shannon–Weaver diversity index of phytoplankton (P-H), zooplankton (Z-H), benthic macroinvertebrate (B-H) and fish density (F-D) are not sensitive to landscape pattern changes; at the riparian scale, F-IBI, B-S and zooplankton density (Z-D) have significant correlations with 9 of 10 landscape metrics calculated in this study, whereas P-S, P-H, Z-H, B-H, F-D and species richness of fish have very low correlations with riparian landscape pattern changes. At the basin scale, no landscape pattern metrics show obviously more influence on the riverine ecosystems than other metrics. At the riparian scale, Shannon's diversity index is a very influential factor. As to both of the two scales, B-S and F-IBI are correlated with most landscape metrics. The information derived above can help understand the impacts of landscape change on river ecosystems more clearly and provide useful scientific information on river ecosystem protection from the viewpoint of landscape. Copyright © 2013 John Wiley & Sons, Ltd.