|
|
|
Impact of Climate and Land-Use Changes on Water Security for Agriculture in Northern China |
QIU Guo-yu, YIN Jin , Shu Geng |
1.Key Laboratory for Urban Habitat Environment Science and Technology, School of Environment and Energy, Shenzhen Graduate School of Peking University, Shenzhen 518055, P.R.China
2.Department of Plant Sciences, University of California, Davis, CA 95616, USA
3.China Institute of Water Resources and Hydropower Research, Beijing 100038, P.R.China |
|
|
摘要 North China is the most important food basket of China, where the majority of wheat and corn are produced. Most crops grown in North China are irrigated, thus water security is food security. Since the 1980s, drying has been frequently observed, as shown by a reduction in precipitation, cutoff in riverflow, and shrinkage of lakes. This increase in drying cannot be explained by climate change alone. We propose that intensive land-use in this area in recent decades has had a significant impact. The objectives of the study are to develop a quantitative model of the concurrent processes of climate change and land-use in North China, and to estimate the relative contributions of each on the observed drying. We integrated relevant socioeconomic data, land-use data, and climate data in the model, and carried out a detailed multitemporal (decade, year, day) analysis. Results showed that land-use has greatly changed since 1999. This change is mainly associated with an extremely important 1999 national policy of “returning farmland and grazing land to forest and grassland”. We found an interesting interaction between climate change and land use policy on riverflow, runoff, and evapotranspiration. During 1970s and 1980s, climate change explained more than 80%, while the land-use change explained only 10% of the riverflow change. The relative contributions were 45 and 45% in the 1980s-1990s and 35 and 55% in the 1990s-2000s respectively for climate change and land-use change. Since the 1990s land-use change has also contributed more to runoff change than climate change. The opposite trend was found for changes in evapotranspiration. Water availability for agriculture in northern China is simultaneously stressed by extensive changes in land-use and rapid climate change. Adaptation of ecological principles, such as the “returning farmland/grazing land to forest and grassland” policy, and other adjustments of economic developmental strategies can be effective tools to mitigate the water shortage problem in northern China and promote sustainable agricultural and food development.
Abstract North China is the most important food basket of China, where the majority of wheat and corn are produced. Most crops grown in North China are irrigated, thus water security is food security. Since the 1980s, drying has been frequently observed, as shown by a reduction in precipitation, cutoff in riverflow, and shrinkage of lakes. This increase in drying cannot be explained by climate change alone. We propose that intensive land-use in this area in recent decades has had a significant impact. The objectives of the study are to develop a quantitative model of the concurrent processes of climate change and land-use in North China, and to estimate the relative contributions of each on the observed drying. We integrated relevant socioeconomic data, land-use data, and climate data in the model, and carried out a detailed multitemporal (decade, year, day) analysis. Results showed that land-use has greatly changed since 1999. This change is mainly associated with an extremely important 1999 national policy of “returning farmland and grazing land to forest and grassland”. We found an interesting interaction between climate change and land use policy on riverflow, runoff, and evapotranspiration. During 1970s and 1980s, climate change explained more than 80%, while the land-use change explained only 10% of the riverflow change. The relative contributions were 45 and 45% in the 1980s-1990s and 35 and 55% in the 1990s-2000s respectively for climate change and land-use change. Since the 1990s land-use change has also contributed more to runoff change than climate change. The opposite trend was found for changes in evapotranspiration. Water availability for agriculture in northern China is simultaneously stressed by extensive changes in land-use and rapid climate change. Adaptation of ecological principles, such as the “returning farmland/grazing land to forest and grassland” policy, and other adjustments of economic developmental strategies can be effective tools to mitigate the water shortage problem in northern China and promote sustainable agricultural and food development.
|
Received: 10 November 2011
Accepted:
|
Fund: We acknowledge, with gratitude, the financial support from the National Natural Science Foundation of China (91025008 and 30972421). |
Corresponding Authors:
Correspondence Shu Geng, Tel: +86-755-26032802, E-mail: sgeng@ucdavis.edu, gengxu@pkusz.edu.cn
E-mail: sgeng@ucdavis.edu
|
Cite this article:
QIU Guo-yu, YIN Jin , Shu Geng.
2012.
Impact of Climate and Land-Use Changes on Water Security for Agriculture in Northern China. Journal of Integrative Agriculture, 12(1): 144-150.
|
[1]Bindoff N L. et al. 2007. Impacts, adaptation and vulnerability. In: Solomon S, et al., eds., Climate Change 2007: The Physical Science Basis. Cambridge University Press, Cambridge, United Kingdom and New York. pp. 175-210. [2]Dai A, Trenberth K E. 2004. Diurnal cycle and its depiction in the community climate system model. Journal of Climate, 17, 930-951. [3]Fu C B, An Z S. 2002. Study of aridification in northern China - a global change issue facing directly the demand of nation. Earth Science Frontiers, 9, 271-275. (in Chinese) [4]Geng S, Zhou Y, Zhang M, Smallwood K S. 2001. A sustainable agro-ecological solution to water shortage in North China plain (Huabei). Journal of Environmental Planning and Management, 44, 345-355. [5]Gleick P H. 2002. Soft water paths. Nature, 418, 373. Kalnay E, Cai M. 2003. Impact of urbanization and land-use change on climate. Nature, 423, 528-531. [6]Liu C M, Cheng T W. 1996. Chinese Water Problem Research. Meteorology Press, Beijing, China. pp. 14- 21. (in Chinese) [7]Li L J, Zhang L, Wang H, Wang J, Yang J W, Jiang D J, Li J Y, Qin D Y. 2007. Assessing the impact of climate variabilityand human activities on streamflow from the Wuding River basin in China. Hydrological Processes, 25, 3485-3491. [8]Milly P C D, Dunne K A, Vecchia A V. 2005. Global pattern of trends in streamflow and water availability in a changing climate. Nature, 438, 347-350. [9]Editors of Nature. 2008. A fresh approach to water. Nature, 452, 253. Oki T, Kanae S. 2006. Global hydrological cycles and world water resources. Science, 313, 1068-1072. [10]Qiu G Y, Yin J, Xiong Y J, Zhao S H, Wang P, Wu X Q, Zeng S.2008. Studies on the effects of climatic warming-drying trend and land-use change on the runoff in the Jinghe river basin. Journal of Natural Resources, 23, 211-218. (in Chinese) [11]Qiu G Y, Yin J, Tian F, Geng S. 2011. Effects of the “conversion of cropland to forest and grassland program” on the water budget of the Jinghe River catchment in China. Journal of Environmental Quality, 40, 1745-1755. [12]Schiermeier Q. 2008. A long dry summer. Nature, 452, 270- 273. [13]Vörösmarty C J, Green P, Salisbury J, Lammers R B. 2000. Global water resources: vulnerability from climate change and population growth. Science, 289, 284-288. [14]Wang H, Li J, Ju Y, Yang C. 2007. Remote sensing and modeling of ecosystems for sustainability IV. In: Wei G, Ustin S L, eds., Proceedings of the SPIE. vol. 6679, 66791R. San Diego, CA. Webber M E. 2008. Energy versus water: solving both crises together. Scientific American, Special editions, 1-5. [15]Xie A, Liu H S, Wu C G, Hu H R. 2004. Drying of soil in the central Inner Mongolia region in recent 50-year. Journal of Nanjing Institute of Meteorology, 27, 479-486. (in Chinese) [16]Zhao M. 2002. A theoretical analysis on the effect of water transportation from south to north China on the local climate in the northern part of China. Journal of Nanjing University (Natural Sciences), 38, 271-280. (in Chinese) |
No Suggested Reading articles found! |
|
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
Cited |
|
|
|
|
|
Shared |
|
|
|
|
|
Discussed |
|
|
|
|