Department of Civil and Environmental Engineering, FAMU-FSU College of Engineering, Tallahassee, FL, 32310, USA; Resilient Infrastructure and Disaster Response Center, FAMU-FSU College of Engineering, Tallahassee, FL, 32310, USA.
Department of Civil and Environmental Engineering, FAMU-FSU College of Engineering, Tallahassee, FL, 32310, USA; Resilient Infrastructure and Disaster Response Center, FAMU-FSU College of Engineering, Tallahassee, FL, 32310, USA.
J Environ Manage. 2024 Jun;362:121284. doi: 10.1016/j.jenvman.2024.121284. Epub 2024 Jun 4.
Future changes in land use/land cover (LULC) and climate (CC) affect watershed hydrology. Despite past research on estimating such changes, studies on the impacts of both these nonstationary stressors on urban watersheds have been limited. Urban watersheds have several important details such as hydraulic infrastructure that call for fine-scale models to predict the impacts of LULC and CC on watershed hydrology. In this paper, a fine-scale hydrologic model-Personal Computer Storm Water Management Model (PCSWMM)-was applied to predict the individual and joint impacts of LULC changes and CC on surface runoff attributes (peak and volume) in 3800 urban subwatersheds in Midwest Florida. The subwatersheds a range of characteristics in terms of drainage area, surface imperviousness, ground slope and LULC distribution. The PCSWMM also represented several hydraulic structures (e.g., ponds and pipes) across the subwatersheds. We analyzed changes in the runoff attributes to determine which stressor is most responsible for the changes and what subwatersheds are mostly sensitive to such changes. Six 24-h design rainfall events (5- to 200-year recurrence intervals) were studied under historical (2010) and future (year 2070) climate and LULC. We evaluated the response of the subwatersheds in terms of runoff peak and volume to the design rainfall events using the PCSWMM. The results indicated that, overall, CC has a greater impact on the runoff attributes than LULC change. We also found that LULC and climate induced changes in runoff are generally more pronounced in greater recurrence intervals and subwatersheds with smaller drainage areas and milder slopes. However, no relationship was found between the changes in runoff and original subwatershed imperviousness; this can be due to the small increase in urban land cover projected for the study area. This research helps urban planners and floodplain managers identify the required strategies to protect urban watersheds against future LULC change and CC.
未来的土地利用/土地覆被（LULC）和气候（CC）变化会影响流域水文。尽管过去已经有研究估算这些变化，但对这两个非稳定压力源对城市流域的影响的研究仍然有限。城市流域有一些重要的细节，例如水力基础设施，需要精细的模型来预测 LULC 和 CC 对流域水文的影响。在本文中，我们应用一个精细的水文模型——个人计算机雨水管理模型（PCSWMM）——来预测 LULC 变化和 CC 对中西部佛罗里达州 3800 个城市子流域地表径流特征（峰值和体积）的单独和联合影响。子流域在排水面积、地表不透水率、地面坡度和 LULC 分布方面存在广泛的特征差异。PCSWMM 还代表了子流域内的几个水力结构（如池塘和管道）。我们分析了径流特征的变化，以确定哪个压力源是变化的主要原因，以及哪些子流域对这些变化最为敏感。我们研究了六种 24 小时设计降雨事件（重现期为 5 至 200 年），包括历史时期（2010 年）和未来时期（2070 年）的气候和 LULC。我们使用 PCSWMM 评估了子流域对设计降雨事件的径流峰值和体积的响应。结果表明，总体而言，CC 对径流特征的影响大于 LULC 变化。我们还发现，LULC 和气候引起的径流变化在较大的重现期和排水面积较小、坡度较缓的子流域中更为显著。然而，在径流变化与原始子流域不透水率之间没有发现关系；这可能是由于研究区域预计城市土地覆被的增加很小。这项研究有助于城市规划者和洪泛区管理者确定保护城市流域免受未来 LULC 变化和 CC 影响所需的策略。
