Trend analysis for the flows of green and blue water in the Heihe River basin, northwestern China

Ecological protection and restoration results in a series of complicated changes in land cover. Lack of research on the historical and potential effects of land cover change on ecosystem service value (ESV) hinders decision-making on trade-offs involved in environmental management. To address this gap, the effects of land cover change on ESV in the upper reaches of the Heihe River Basin in northwestern China were evaluated. First, on the basis of land cover maps for 2001, 2008 and 2015, the land cover map for 2029 was predicted with CA-Markov model. Then, the changes in ESV resulting from land cover change were valuated with the benefit transfer method. The results showed that the total ESV increased from $1207.33 million (USD) in 2001 to $1479.48 million (USD) in 2015, and the value was expected to reach $1574.53 million (USD) in 2029. The increase in ESV can be mainly attributed to expansion in areas of wetland. In this study, the elastic index was applied to identify areas that were more sensitive to ecological management, aiding in selecting sites for investment in ecological protection and restoration programs. Furthermore, the potential effects of land cover change on ESV was evaluated. The results are of great importance for guiding future ecological management.

Download Full-text

Water Environmental Degradation of the Heihe River Basin in Arid Northwestern China

Environmental Monitoring and Assessment ◽

10.1007/s10661-005-3912-6 ◽

2005 ◽

Vol 108 (1-3) ◽

pp. 205-215 ◽

Cited By ~ 71

Author(s):

Shan-Zhong Qi ◽

Fang Luo

Keyword(s):

River Basin ◽

Environmental Degradation ◽

Heihe River Basin ◽

Northwestern China ◽

Heihe River ◽

Arid Northwestern China ◽

The Heihe River Basin

Download Full-text

Assessment of spatial and temporal patterns of green and blue water flows under natural conditions in inland river basins in Northwest China

Hydrology and Earth System Sciences ◽

10.5194/hess-16-2859-2012 ◽

2012 ◽

Vol 16 (8) ◽

pp. 2859-2870 ◽

Cited By ~ 90

Author(s):

C. F. Zang ◽

J. Liu ◽

M. van der Velde ◽

F. Kraxner

Keyword(s):

River Basin ◽

River Basins ◽

Heihe River Basin ◽

Green Water ◽

Heihe River ◽

Blue Water ◽

Natural Conditions ◽

Water Flows ◽

Inland River ◽

Green And Blue Water

Abstract. In arid and semi-arid regions freshwater resources have become scarcer with increasing demands from socio-economic development and population growth. Until recently, water research and management has mainly focused on blue water but ignored green water. Furthermore, in data poor regions hydrological flows under natural conditions are poorly characterised but are a prerequisite to inform future water resources management. Here we report on spatial and temporal patterns of both blue and green water flows that can be expected under natural conditions as simulated by the Soil and Water Assessment Tool (SWAT) for the Heihe river basin, the second largest inland river basin in Northwest China. Calibration and validation at two hydrological stations show good performance of the SWAT model in modelling hydrological processes. The total green and blue water flows were 22.05–25.51 billion m3 in the 2000s for the Heihe river basin. Blue water flows are larger in upstream sub-basins than in downstream sub-basins mainly due to high precipitation and a large amount of snow and melting water in upstream. Green water flows are distributed more homogeneously among different sub-basins. The green water coefficient was 87%–89% in the 2000s for the entire river basin, varying from around 80%–90% in up- and mid-stream sub-basins to above 90% in downstream sub-basins. This is much higher than reported green water coefficients in many other river basins. The spatial patterns of green water coefficients were closely linked to dominant land covers (e.g. snow cover upstream and desert downstream) and climate conditions (e.g. high precipitation upstream and low precipitation downstream). There are no clear consistent historical trends of change in green and blue water flows and the green water coefficient at both the river basin and sub-basin levels. This study provides insights into green and blue water endowments under natural conditions for the entire Heihe river basin at the sub-basin level. The results are helpful to benchmark the natural flows of water in the basin as part of improved water resources management in the inland river basins of China.

Download Full-text