Spatiotemporal Dynamics of Ecosystem Services Driven by Human Modification over the Past Seven Decades: A Case Study of Sihu Agricultural Watershed, China

Abstract

Understanding the effects of human modification on ecosystem services is critical for effectively managing multiple services and achieving long-term sustainability. The historical dynamics of ecosystem services are important for detecting the impacts before and after intensive modification and deserve further study. To this end, we quantified the spatiotemporal dynamics of 11 ecosystem services across the Sihu agricultural watershed in 1954, 1983, 2001, and 2018. We used the Spearman coefficient, self-organized maps clustering, and redundancy analysis to explore the spatial patterns and potential modification drivers of temporal variations of ecosystem service provision. The results revealed the following: (1) The spatial correlations among ecosystem services in a single year were inconsistent with the ecosystem service change associations during two-time steps. The snapshot correlations at one time led to misunderstandings (such as water yield and runoff control or soil carbon sequestration, and habitat quality changed direction from synergy to trade-off) and missed synergies (such as water purification and recreational potential); (2) Most ecosystem services could be synergetic in one bundle with multifunctionality before intensive modification, but later transformed to single or limited services dominated bundles, especially in lake-polder areas; (3) Lake reclamation and hydraulic infrastructure were the most significant modification indicators explaining the variation of ecosystem services (30.9% of variance explained by lake reclamation in 1954, 38.2% of variance explained by hydraulic infrastructure in 2018). Meanwhile, changes in dominant drivers also indicated the transition from lake-based ecosystem service supply to engineered service. An improved understanding of the spatiotemporal pattern of ecosystem services and the underlying human modification influence is vital for realizing the sustainability and multifunctionality of agricultural watershed.