| In this paper, the water-consuming characteristic of Salix psammophila seedlings from Minqin county in Gansu province, Yanchi county in Ninxia province, Dalateqi and Wushenqi in inner Mongolia and Yulin in Shanxi province were studied with the method of simulated drought in greenhouse combining with experiments about their adaptability in order to choose water-saving and drought-resistant Salix psammophila provenances fit for the arid and semi-arid areas of Northern China; Simultaneously, application of advanced technique of drought-resistance for afforestation (for example, solid water, foliage fertilizer and so on) were studied to provide references and practically methods of reconstruction of forest vegetation for sand prevention and control in the arid and semi-arid area in China.The result of the studies on water consumption of seedlings both in normal water supply and water stress conditions showed that: in normal water supply condition, The average ratio of the maximum water consuming rate of seedlings and the average rate of daily water consuming rate of seedlings is 1.56, the average of ratio of the maximum photosynthesis rate and the average rate daily photosynthesis rate is 1.54, the average of ratio of the maximum respiration rate and the average of rate daily respiration rate is 1.60. These conclusions show the ratio of the respiration (water consuming ), photosynthesis rate and the average rate have a steady relation in all kinds of trees. According to the ratio, the respiration water consuming and productivity of photosynthesis in a whole day can be calculated by measuring the maximum of instantaneous rate. In addition, the order of respiration rate of 5 Salix psammophila provenance does not accord with that of water consuming in normal water condition, but the total trend is very similar .i.e. the water consuming rate of seedling from Yanchi is more higher , the water consuming rate of seedling from Yulin and Minqin is more lower . However , the respiration rate accord with water consuming rate in aspect of the ratio of the maximum rate and the average rate .In normal water supply condition , the total daily water consumption of seedlings from Minqin, Yanchi, Dalate, Wushenqi and Yulin was respectively 167.30g·d-1, 214.58 g·d-1,176.28 g·d-1, 156.85 g·d-1,和 121.31 g·d-1, however, the total daily water consumption was respectively 32.42 g·d-1,27.90 g·d-1,27.06 g·d-1,39.16 g·d-1和38.80 g·d-1, respectivelydecreased to 19.4%, 12.6%, 15.4%, 21.1% and 31.9% of that in normal water condition, water consuming rate of seedlings from Minqin was on the lowest level provenance in the course of experience; seedlings from Yanchi had the highest water consuming rate in normal water supply, and the water consuming rate decreased greatly after water stress; seedlings from Yulin and Wushenqi did not decrease too much, and the water consuming rate came to more high at the end of the experiment; Dalate were at the middling during the whole experiment. Along with the water consuming research, the response to water stress of seedlings from five provenances at different water condition was also studied from the following aspects as leaf water potential, leaf water content, photosynthesis rate, respiration rate and water use efficiency. The result shows that, compared with the other provenances, seedlings from Minqin had the greater drought-resistance capability, while photosynthesis rate of seedlings from Dalate was the highest in normal water supply, which make sense for its growthThree aspects as survival rate, height growth and number of ramification were compared in the adaptability ability of seedlings in the field. The result showed that, in the three experimental places, average survival rate of seedlings from Minqin is the highest; while at the aspect of growing condition, both the height growth and the number of ramification of the seedlings from Dalate were upper.The application of solid water and foliar fertilizer on forestation showed that, both of th...
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