陶粒覆盖对土壤水分、植物光合作用及生长状况的影响

以河北省廊涿高速公路中央隔离种植槽为研究地点,探讨陶粒覆盖对土壤水分、植物光合作用及生长状况的影响,结果表明:(1)陶粒覆盖有效地提高了土壤含水量,减弱了不同土层、不同月份之间的差距,两层覆盖(M2)效果要好于一层覆盖(M1)。从10-60 cm土层,陶粒覆盖对土壤含水量的影响逐渐降低,裸露地面的土壤含水量和陶粒覆盖下的土壤含水量的差距逐渐减弱。越是干旱季节,陶粒覆盖保水效果越明显;(2)陶粒覆盖对月季、大叶黄杨的净光合速率(P_n)、蒸腾速率(T_r)、水分利用效率(WUE)均产生了影响。两植物一天当中任何测量时刻的P_n均为M2>M1>MD(裸地)。陶粒覆盖也提高了月季、大叶黄杨的T_r日均值,使其日变化峰值出现时间发生变化。陶粒覆盖对WUE影响要远远小于对P_n、T_r的影响,相互之间差异均不显著。由于大叶黄杨的抗旱性较差,陶粒覆盖对大叶黄杨光合特性的影响大于对月季的影响。(3)陶粒覆盖大大提高了紫叶小檗、侧柏、小叶黄杨、大叶黄杨、月季5种植物的成活率,增加了植物的地径、株高增长量,M2的效果均好于M1。

Effects of ceramsite mulching on soil water content, photosynthetic physiological characteristics and growth of plants

In this study, we investigated the effects of a combination of surface coverage and planting as well as the effects of ceramsite mulching on soil water content and the photosynthetic physiological characteristics of plants located in the central isolation belt of Langzhuo Highway in Hebei Province. The results were as follows: (1) Ceramsite mulching increased the soil water content, reduced the soil water content disparity among soil depths and months, and provided a more stable environment for growth. In addition, two layers of ceramsite (M2) had better effects than did a single layer of ceramsite (M1). The overall order of soil water content in soil at different depths or during different months was as follows: two layers of ceramsite (M2)> a single layer of ceramsite (M1)> bare soil (MD). The effects of ceramsite mulching on soil water content decreased with soil depth from 10 to 60 cm, while the difference in soil water content between bare soil and areas subject to ceramsite mulching was gradually reduced at these depths. During greater drought months, the effects of ceramsite mulching on soil water were obvious. (2) Moreover, ceramsite mulching had an impact on the net photosynthesis (P_n), transpiration (T_r) and water use efficiency (WUE) of Euonymus japonicus and Rosa chinensis. Specifically, the order of net photosynthesis (P_n) of the two plants at any time of the measurement day was two layers of ceramsite (M2)> a single layer of ceramsite (M1) >bare soil (MD). Furthermore, the average net photosynthesis (P_n) of the two plants was greatly improved under two layers of ceramsite (M2). The average transpiration (T_r) of the two plants also improved, and the spike times changed in response to ceramsite mulching. Variations in the water use efficiency (WUE) among the two plants were affected by ceramsite mulching, with the order of diurnal averages being two layers of ceramsite (M2)>a single layer of ceramsite (M1)> bare soil (MD); however, the differences between each other were not significant. Moreover, the effects of ceramsite mulching on water use efficiency (WUE) were much lower than the effects on net photosynthesis (P_n) and transpiration (T_r). Because the drought-resistance of Euonymus japonicus was worse than that of Rosa chinensis, the effects of ceramsite mulching on Euonymus japonicus were greater than on Rosa chinensis. (3) Ceramsite mulching affected plant survival and growth through its effects on soil and the other conditions of plant growth. Specifically, ceramsite mulching greatly improved the survival rates of Euonymus japonicus L, Platycladus orientalis Franco, Rosa chinensis Jacq, Berberis thumbergii cv.atropurpurea and Euonymus japonicus L and increased the growth of diameter at breast height and the height of all five of these plants. The order of survival rates, growth of diameter at breast height and height of the five plants were as follows: two layers of ceramsite (M2)>a single layer of ceramsite (M1)>bare soil (MD). M2 showed better results than M1, but there were no significant differences between two layers of ceramsite (M2) and a single layer of ceramsite (M1).