Redai dili (Apr 2024)
Blue-Green Spatial Evaluation of Tropical Rainforest Areas from the Perspective of Water Ecosystem Resilience: A Case Study of the Nansheng River in Wuzhishan City
Abstract
In tropical rainforest regions, rivers face significant challenges from stormwater, flooding, and human activities, making the construction of resilience in their blue-green spaces critical for overall habitat sustainability. While domestic and international studies have focused on resilient flood management practices and quantitative resilience evaluations, there is a lack of assessments specifically addressing the resilience of river blue-green spaces under different ecological pressure impacts. To address this gap, this study incorporates the "pulse" and "pressure" methods into the Pressure-Pulse-Resilience model to measure the resilience of blue-green spaces. This study also develops a theoretical framework for the resilience of aquatic ecosystems by linking societal and ecological factors. The resilience evaluation route consists of four steps: theoretical model construction, pressure-bearing evaluation superposition, analysis of coincidence and conflict points, and resilience planning strategy layout. To achieve the two main objectives of ensuring a balance between water supply and demand for both water security patterns and ecosystem services, this thesis delves into the regulatory mechanisms of river resilience, adaptation, and recovery, providing valuable insights into the spatial resilience planning of rivers in such regions. By focusing on the Nansheng river in Wuzhishan city as a practical case, this study conducted a multidimensional resilience assessment to cope with the frequent occurrence of water security vulnerable zones or the imbalance between the supply and demand of ecosystem services under double ecological pressure. Using advanced simulation methods, such as the SCS-CN model, the Equivalent Factor Approach, and the Hot Spot Analysis Method, the study identified distinct zones that are prone to stormwater and flood inundation, zones at risk of water safety threats, and zones experiencing a mismatch between water supply and demand in the blue-green space. Based on the identification of resilience deficiencies, including multiple stormwater threat zones, an imbalance between supply and demand of ecosystem services, and the seasonal nature of slow pressures, the thesis proposes three planning strategies: first, an ecological security pattern and zoning control approach is suggested based on stormwater and flood pulses to improve the resilience to cope with sudden pulses, following the principle of bottom-line control. Second, a demand-oriented blue-green space planning and service supply strategy was proposed to coordinate the slow-onset pressure on the blue-green spaces of rivers caused by the demands of residents for daily life and recreation, integrating land space and other related planning to balance the supply and demand of the social-ecological system. Lastly, the study advocates for the construction of dynamic and adaptive resilience facilities that cater to the seasonal changes in ecological pressure faced by the blue-green space in tropical rainforest regions, in fulfillment of multidimensional and multilevel water resilience requirements, that is, water security, water ecology, water landscape, water function, and water vitality. In summary, this study presents an innovative theoretical framework for water ecosystem resilience, utilizing the measurable concepts of "pulse" and "pressure." Through an empirical case study of the Nansheng river in Wuzhishan city, this dissertation established a region-specific evaluation path for the spatial resilience of rivers in tropical rainforest areas.
Keywords
