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Climate change and human activity are two linked factors that alter the spatiotemporal distribution of the available water. Assessing the relative contribution of the two factors on runoff changes can help the planners and managers to better formulate strategies and policies regarding regional water resources. In this work, using two typical sub-basins of the Yellow River as the study area, we first detected the trend and the breakpoint in the annual streamflow data with the Pettitt test during the period 1964–2011. Next, a Budyko-based climate elasticity model and a monthly hydrological model were employed as an integrated method to distinguish the relative contributions of climate change and human activities to the long-term changes in runoff. The results showed that a significant decline in the annual runoff occurred in the two sub-basins during the study period, and the abrupt change point in the annual runoff at the two sub-basins both occurred in 1997. The conceptual hydrological model performed well in reproducing monthly runoff time series at the two sub-basins. The Nash-Sutcliffe efficiency (NSE) between observed and simulated runoff during the validation period exceeds 0.83 for the two sub-basins. Climate elasticity method and hydrological model give consistent attribution results: human activities are the major drivers responsible for the decreased annual runoff in the Ten Great Gullies Basin. The relative contributions of climate change and human activities to the changes in the annual runoff were 22–32% and 68–78%, respectively.

This situated case study outlines how a place-based landscape template provided an integrative platform for the environmental arm of a cross-disciplinary international education initiative, the Three Brothers Project, wherein geographers at the University of Auckland worked alongside engineers at Tsinghua University in Beijing to support collaborative research with grassland and agricultural scientists at Qinghai University in western China. These collaborative efforts built upon strategic leadership at government and university level, an appropriate resource base and engaged practitioners who developed and embedded research opportunities that built upon a shared commitment to research on environmental values in the source zone of the Yellow River. We highlight how a landscape framing brought together divergent mindsets, methodologies and practices in this collaborative research, providing an effective platform to share experiences, discuss perspectives and develop research outcomes.

Meandering channel with distorted bends develops along the Tarim River, the longest dryland river in China. The river bank and bed is majorly composed of coarse silt and fine sand and almost none clay content, making the bank strength very low. The development of meander bend in such environment hence is somehow irrational. We preliminarily investigate the effects of riparian vegetation root on bend development in this region through examining the root cohesion and its enhancement on bank stability. In-situ measurements and sampling of roots from local typical riparian vegetation (i.e., populous, Tamarix, and Phragmites Australis) were conducted to obtain root parameters like diameter and root area ratio. Local bend curvature corresponding to sampling sites are also obtained. BSTEM model is used to quantitatively estimate the effects of different root conditions on improving channel bank strength. Four vegetation root scenarios were modelled, i.e., tree (populous), shrub (Tamarix), grass (Phragmites Australis) and no root. The results show that root supplies effective cohesive reinforcement for the channel bank and enhances the bank safety factors (Fs). Riparian vegetation should be a necessary condition for development of meandering channel in Tarim River.