Chaire de recherche en eau potable, École Supérieure d'aménagement du territoire et de Développement Régional, Université Laval, 1624 Pavillon F.A. Savard, Ste-Foy, QC G1K 7P4, Canada.
Chaire de recherche en eau potable, École Supérieure d'aménagement du territoire et de Développement Régional, Université Laval, 1624 Pavillon F.A. Savard, Ste-Foy, QC G1K 7P4, Canada.
Sci Total Environ. 2014 Sep 15;493:1014-24. doi: 10.1016/j.scitotenv.2014.06.087. Epub 2014 Jul 10.
Surface water quality is particularly sensitive to land use practices and climatic events that affect its catchment. The relative influence of a set of watershed characteristics (climate, land use, morphology and pedology) and climatic variables on two key water quality parameters (turbidity and fecal coliforms (FC)) was examined in 24 eastern Canadian catchments at various spatial scales (1 km, 5 km, 10 km and the entire catchment). A regression analysis revealed that the entire catchment was a better predictor of water quality. Based on this information, linear mixed effect models for predicting turbidity and FC levels were developed. A set of land use and climate scenarios was considered and applied within the water quality models. Four land use scenarios (no change, same rate of variation, optimistic and pessimistic) and three climate change scenarios (B1, A1B and A2) were tested and variations for the near future (2025) were assessed and compared to the reference period (2000). Climate change impacts on water quality remained low annually for this time horizon (turbidity: +1.5%, FC: +1.6%, A2 scenario). On the other hand, the influence of land use changes appeared to predominate. Significant benefits for both parameters could be expected following the optimistic scenario (turbidity: -16.4%, FC: -6.3%; p < 0.05). However, pessimistic land use scenario led to significant increases on an annual basis (turbidity: +11.6%, FC: +15.2%; p < 0.05). Additional simulations conducted for the late 21st century (2090) revealed that climate change impacts could become equivalent to those modeled for land use for this horizon.
地表水质对影响其集水区的土地利用实践和气候事件特别敏感。在各种空间尺度（1 公里、5 公里、10 公里和整个集水区）下，对一组流域特征（气候、土地利用、形态和土壤学）和气候变量对两个关键水质参数（浊度和粪大肠菌群（FC））的相对影响进行了检查。回归分析表明，整个集水区是水质的更好预测指标。根据这些信息，开发了用于预测浊度和 FC 水平的线性混合效应模型。考虑并在水质模型中应用了一组土地利用和气候情景。测试并比较了四个土地利用情景（无变化、相同变化率、乐观和悲观）和三个气候变化情景（B1、A1B 和 A2）的近未来（2025 年）变化与参考期（2000 年）。对于这一时限（浊度：+1.5%，FC：+1.6%，A2 情景），气候变化对水质的影响仍然较低。另一方面，土地利用变化的影响似乎占主导地位。在乐观情景下，两个参数都有望显著受益（浊度：-16.4%，FC：-6.3%；p<0.05）。然而，悲观的土地利用情景导致每年都有显著增加（浊度：+11.6%，FC：+15.2%；p<0.05）。为 21 世纪末（2090 年）进行的其他模拟表明，气候变化的影响可能与该时段土地利用模型的影响相当。
