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Land Use/Cover Change in the Middle Reaches of the Heihe River Basin over 2000-2011 and Its Implications for Sustainable Water Resource Management.

Hu X, Lu L, Li X, Wang J, Guo M - PLoS ONE (2015)

Bottom Line: From the 1960s to the 1990s, the downstream flow in the HRB declined as a result of large, artificial changes in the distribution of water and land and a lack of effective water resource management.The results show that the most significant land use/cover change in the middle reaches of the HRB was the continuous expansion of farmland for economic interests.The results of this study can also serve as a reference for the sustainable management of water resources in other arid inland river basins.

View Article: PubMed Central - PubMed

Affiliation: Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, 320 Donggang West Road, Lanzhou, 730000, China.

ABSTRACT
The Heihe River Basin (HRB) is a typical arid inland river basin in northwestern China. From the 1960s to the 1990s, the downstream flow in the HRB declined as a result of large, artificial changes in the distribution of water and land and a lack of effective water resource management. Consequently, the ecosystems of the lower reaches of the basin substantially deteriorated. To restore these degraded ecosystems, the Ecological Water Diversion Project (EWDP) was initiated by the Chinese government in 2000. The project led to agricultural and ecological changes in the middle reaches of the basin. In this study, we present three datasets of land use/cover in the middle reaches of the HRB derived from Landsat TM/ETM+ images in 2000, 2007 and 2011. We used these data to investigate changes in land use/cover between 2000 and 2011 and the implications for sustainable water resource management. The results show that the most significant land use/cover change in the middle reaches of the HRB was the continuous expansion of farmland for economic interests. From 2000 to 2011, the farmland area increased by 12.01%. The farmland expansion increased the water resource stress; thus, groundwater was over-extracted and the ecosystem was degraded in particular areas. Both consequences are negative and potentially threaten the sustainability of the middle reaches of the HRB and the entire river basin. Local governments should therefore improve the management of water resources, particularly groundwater management, and should strictly control farmland reclamation. Then, water resources could be ecologically and socioeconomically sustained, and the balance between upstream and downstream water demands could be ensured. The results of this study can also serve as a reference for the sustainable management of water resources in other arid inland river basins.

No MeSH data available.


Case 1: farmland area changes in Xusanwan, Gaotai County, from 2000 to 2007, driven by migrants.
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pone.0128960.g004: Case 1: farmland area changes in Xusanwan, Gaotai County, from 2000 to 2007, driven by migrants.

Mentions: Land use/cover change is often correlated with the implementation of national policy [49], which has been considered a major factor of land use/cover change [50–51]. In the framework of the EWDP, the ecological migration and ‘grain-for-green’ policies were implemented in the middle reaches of the HRB. The impact of these polices on the expansion and abandonment of farmland is obvious. In the middle reaches of the HRB, the regional expansion of farmland was at least partly driven by migrants. Figs 2 and 4 show an example of this phenomenon. Farmland reclamation was very common in Xusanwan, Gaotai County because of the large number of immigrants from the piedmont irrigation district. As a result, the total area of farmland in this region increased by 45% between 2000 and 2007. The ‘grain-for-green’ policy also had an effect on the proportion of the landscape covered by farmland. The main feature of this program provided free grain and cash payments to participating farmers who converted farmland to forests and grassland [52]. After the implementation of the ‘grain-for-green’ policy, arboreal forests, shrub forests, thick grasslands and moderate grasslands in the middle reaches of the HRB increased, albeit by varying degrees (7.76%, 12.78%, 21.88% and 2.91%, respectively), between 2000 and 2007. However, in recent years, some farmers who converted farmland to grassland were not compensated with grain or cash. This outcome, and the price increase for agricultural products, has led farmers to plant crops on farmland that had been converted to grassland or to reclaim new farmland. In the field survey, we also observed that much desert, sparse grassland, sparse forest and overflow land had been reclaimed as farmland by local people (Fig 5).


Land Use/Cover Change in the Middle Reaches of the Heihe River Basin over 2000-2011 and Its Implications for Sustainable Water Resource Management.

Hu X, Lu L, Li X, Wang J, Guo M - PLoS ONE (2015)

Case 1: farmland area changes in Xusanwan, Gaotai County, from 2000 to 2007, driven by migrants.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4482701&req=5

pone.0128960.g004: Case 1: farmland area changes in Xusanwan, Gaotai County, from 2000 to 2007, driven by migrants.
Mentions: Land use/cover change is often correlated with the implementation of national policy [49], which has been considered a major factor of land use/cover change [50–51]. In the framework of the EWDP, the ecological migration and ‘grain-for-green’ policies were implemented in the middle reaches of the HRB. The impact of these polices on the expansion and abandonment of farmland is obvious. In the middle reaches of the HRB, the regional expansion of farmland was at least partly driven by migrants. Figs 2 and 4 show an example of this phenomenon. Farmland reclamation was very common in Xusanwan, Gaotai County because of the large number of immigrants from the piedmont irrigation district. As a result, the total area of farmland in this region increased by 45% between 2000 and 2007. The ‘grain-for-green’ policy also had an effect on the proportion of the landscape covered by farmland. The main feature of this program provided free grain and cash payments to participating farmers who converted farmland to forests and grassland [52]. After the implementation of the ‘grain-for-green’ policy, arboreal forests, shrub forests, thick grasslands and moderate grasslands in the middle reaches of the HRB increased, albeit by varying degrees (7.76%, 12.78%, 21.88% and 2.91%, respectively), between 2000 and 2007. However, in recent years, some farmers who converted farmland to grassland were not compensated with grain or cash. This outcome, and the price increase for agricultural products, has led farmers to plant crops on farmland that had been converted to grassland or to reclaim new farmland. In the field survey, we also observed that much desert, sparse grassland, sparse forest and overflow land had been reclaimed as farmland by local people (Fig 5).

Bottom Line: From the 1960s to the 1990s, the downstream flow in the HRB declined as a result of large, artificial changes in the distribution of water and land and a lack of effective water resource management.The results show that the most significant land use/cover change in the middle reaches of the HRB was the continuous expansion of farmland for economic interests.The results of this study can also serve as a reference for the sustainable management of water resources in other arid inland river basins.

View Article: PubMed Central - PubMed

Affiliation: Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, 320 Donggang West Road, Lanzhou, 730000, China.

ABSTRACT
The Heihe River Basin (HRB) is a typical arid inland river basin in northwestern China. From the 1960s to the 1990s, the downstream flow in the HRB declined as a result of large, artificial changes in the distribution of water and land and a lack of effective water resource management. Consequently, the ecosystems of the lower reaches of the basin substantially deteriorated. To restore these degraded ecosystems, the Ecological Water Diversion Project (EWDP) was initiated by the Chinese government in 2000. The project led to agricultural and ecological changes in the middle reaches of the basin. In this study, we present three datasets of land use/cover in the middle reaches of the HRB derived from Landsat TM/ETM+ images in 2000, 2007 and 2011. We used these data to investigate changes in land use/cover between 2000 and 2011 and the implications for sustainable water resource management. The results show that the most significant land use/cover change in the middle reaches of the HRB was the continuous expansion of farmland for economic interests. From 2000 to 2011, the farmland area increased by 12.01%. The farmland expansion increased the water resource stress; thus, groundwater was over-extracted and the ecosystem was degraded in particular areas. Both consequences are negative and potentially threaten the sustainability of the middle reaches of the HRB and the entire river basin. Local governments should therefore improve the management of water resources, particularly groundwater management, and should strictly control farmland reclamation. Then, water resources could be ecologically and socioeconomically sustained, and the balance between upstream and downstream water demands could be ensured. The results of this study can also serve as a reference for the sustainable management of water resources in other arid inland river basins.

No MeSH data available.