Integrated modelling for sediment management in a watershed of dynamic land use

本研究的主要目的是对动态土地利用分水岭的泥沙管理进行综合模拟。在尼泊尔选择了一个由丘陵和平坦地形组成的分水岭，以评估山丘的泥沙产量及其对平坦地形河床演变的影响。去年，我们分析了研究区在气候变化下的产沙量。我们发表了两篇同行评议的期刊论文。研究区域的泥沙产生量是在基线时间段内进行的。通过实地考察，收集了与水文气象、土壤、土地利用、海拔和地形数据有关的不同数据。我们还评估了公民科学(CS)数据在尼泊尔加德满都山谷一个小流域管理中的适用性。利用实测资料对产沙量估算模型进行了验证。然后使用不同的气候模型预测不同未来时间段的沉积物产量：近期(2025-2050年)、中期(2051年-2075年)和远期(2076-2100年)。估算采用了基于物理模型和经验模型两种方法。目前，有两篇稿件正在审阅中：1)《国际气候学杂志》；2)《水文科学杂志》。前者侧重于当前和未来情景下研究区极端降水指数的时空分布，后者侧重于极端降水事件期间的降雨径流和淹没模拟。我们现在将重点放在改变LULC上。

The main purpose of our study is to conduct integrated modelling for sediment management in a watershed of dynamic land use. A watershed in Nepal that consists of both hilly and flat terrain was selected to assess sediment yield from the hill and its effects on riverbed evolution at flat terrain. Last year, we analysed the sediment yield of the study area Under the changing climate. We published two peer-reviewed journal papers.The sediment yield of the study area was carried out under a baseline time period. From the field visits, different data related to hydro-meteorology, soil, land use land cover (LULC), elevation, and topographical data were collected. We also evaluated the applicability of citizen-science (CS) data for watershed management in a small watershed in Kathmandu valley, Nepal. The sediment yield estimation model was validated with the observed data. Then sediment yields are projected for different future time periods: the near-future (2025-2050), mid-future (2051-2075) and far-future (2076-2100) under different warming scenarios using different climate models. Both physically-based models and empirical models were employed for the estimation.Currently, two manuscripts are under review: 1) International Journal of Climatology and 2) Hydrological Sciences Journal. The first one focuses on spatio-temporal distribution of extreme precipitation indices in the study area in both present and future scenarios whereas the latter focuses on rainfall-runoff and inundation modelling during extreme precipitation events. We would now focus on changing LULC.