【摘要】 荒漠化和沙尘暴不仅影响西北地区,同时也影响到相邻地区的国民经济的发展和人民生活的改善。虽然,我国政府历年来都十分重视西北地区的生态条件的改善和环境的建设,但我国沙尘暴的频次和强度在未来几年仍有增加之势。C4(碳四)植物具有高光饱和点、高光合速率和高光合生产效率的生理特性。比C3(碳三)植物耗水少,而光合效率高。对土壤的适应性广,具有较强的竞争力。它应是优先考虑的干旱区水土保持植物。从美国选育的C4纤维禾草可以看出,多年生的C4纤维禾草具有:①光合效率高,而水耗低;②多年生可节省每年播种所需的种、肥和耕作费用,节省生产成本;③强大的根系可使植物体内的氮元素储存起来,提高了土壤养分的利用率等特点。它是干旱区中一种既节水,又是水土保持最有成效的植物资源,对缓解西北地区的荒漠化问题将会发挥巨大的作用。我国温带地区的草本植物资源丰富,其中有不少的C4植物。建议开展C4草本植物和木本植物的选育、引种和推广研究,以在半荒漠地区营造一个环境良好、人与自然和谐的家园。更多还原

【Abstract】 Desertification and sandstorm affect the economic development and the improvement of the people’s livelihood not only in northwest China but also in the adjacent regions.Although the governments at all levels pay great attention to the improvement of ecological conditions and the environmental regeneration in northwest China all along,the occurring frequency and intensity of sandstorms will be in an increase trend in China in near future.C₄ plants have the physiological properties of high light saturation point,high photosynthetic efficiency and high photosynthetic productive efficiency.Water consumption of C₄ plants is less but their photosynthetic efficiency is higher than that of C₃ plants,and their adaptability to soils is wide.C₄ plants should be preferentially selected as the plants in water and soil conservation in arid areas.C₄ plants bred in USA have following properties:（1） Their photosynthetic efficiency is high but their water consumption is low;（2） Some costs in seeds,fertilizers and cultivation of C₄ plant growing can be saved because C₄ plants are perennial;（3） Some nitrogen can be stored in C₄ plants because their roots develop well,and the utilization ratio of soil nutrient can be increased.C₄ plants are the plant resources in water saving and water and soil conservation in arid areas,and they can play an important role in desertification control in northwest China.It is rich in herbage resources in the temperate regions in China,and there are many species of C₄ plants.Therefore,it is suggested to carry out the study on breeding,introduction and popularization of herbaceous and woody plants so as to construct a human-nature harmonious homestead with fine environment in semiarid regions in northwest China.更多还原