Conclusions

The sensitivity of hydrologic process and water balance to changes in climatic and land use conditions varied from watershed to watershed. In our study, two hydrological models fitted for mountain and lowland artificial watersheds respectively were applied in Lake Taihu basin to evaluate the seasonal and annual characteristics of hydrological variables and their driving factors, which were not fully understood in previous studies. We found that climate change caused a larger increase of annual runoff in mountain watersheds than that in lowland artificial watersheds, which opposite to the influence of land use change. The scenario of converting cultivate land to residential land increased the discharge mostly comparing to other land use scenarios. In addition, these variations were most notable in May in mountain watersheds, comparing to rice seasons in lowland artificial watersheds. Runoff variation in mountain watersheds were most attributed to climate change. However, the influence of land use change was equally important in the lowland artificial watersheds. Land use change can enhance climate impacts on water balance in lowland artificial watersheds. This study improved our understandings on the different hydrological responses to single and synergetic changes in climate and land use varying watershed characteristics, and can thus support water managers to project the future variation of hydrology and water resources in management practice.