An In-Depth Assessment of Water Resource Responses to Regional Development Policies Using Hydrological Variation Analysis and System Dynamics Modeling

To maintain sustainability and availability of regional water resources, appropriate integrated water resource management (IWRM) should be based on an assessment of water resource background and responses to regional development and utilization policies. The study proposed an assessment method combining hydrological variation analysis with a system dynamics (SD) model to support IWRM in the Baiyangdian Region, Northern China. Integrated variation analysis and attributive analysis were used to identify variation time and causes of runoff. Then, based on the current water resource situation, an accessibility analysis examined the possibility of achieving a water resources supply and demand balance of social economic development and the ecological environment within individual internal management. Finally, an SD model simulated water resource response to development policies to predict future policy impacts. Results showed that 65.18% of the impact on runoff was from human activities. Sustainability goals were impossible through internal management, but with eco-migration policies and 1 × 108 m3 inter-basin transferred water, it could quickly be achieved, and water ecosystem function could also be recovered. Establishment of the Xiong’an New Area necessitated introduction of integrated cross-basin management to protect the Baiyangdian Region from degradation of its ecological function. Our study proposed a new method for comparation of internal and cross-basin IWRM.

Mid-late Holocene hydroclimate variation in the source region of the Yangtze River revealed by lake sediment records

<p>The headwater region of the Yangtze River serves as major constituent of Chinese Water Tower and is critical in providing fresh water for hundreds of millions of people living downstream. Hydrological variation is mainly influenced by environmental changes. Therefore, a good understanding of climate changes in the source region of the Yangtze River (SRYR) is of great significance. Here, we provide a lacustrine sediment core from Saiyong Co in SRYR, northeastern Tibetan Plateau, China, to reconstruct hydrological variation and the main influencing factors based on the analysis of grain size, scanning XRF, loss on ignition (LOI), which cover the past 6 ka. It is remarkable that total organic matter (LOI-550℃) exhibits opposite patterns regarding to the PC1 of XRF, which represents the allochthonous input, indicating the majority of organic matter was mainly yielded within the lake. Clustering of palaeohydrological proxies, such as the reduced PC1 and increase in median grain size, seems coincide with the weakened strength of the Indian summer monsoon, which suggest a generally dry trend in the SRYR during the mid-late Holocene. However, short pulses of outrageous period occurred at 3.8-3.2 ka BP and 1.5-1.0 ka BP. The abrupt increase in PC1 and very coarse silt indicate the lake catchment became more humid with higher surface runoff, which is consistent with weaker lake productivity. The inferred hydrological change in SRYR since 6 ka BP not only have significant environmental influence, but also agree with other sequences from Tibetan Plateau and the adjacent regions This study provides long-term records of paleoenvironmental evolution which is particularly significant to understand recent and to predict future hydrological change in SRYR.</p>