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雪对树木种子有刺激作用,因为雪水里的重水含量比普通水低,氮化物含量比普通水高的缘故,而高量的重水对种子的新陈代谢作用是不利的。同时,雪还能够吸收大气中的氨,氨是植物生长大量需要的元素,因而雪水能提高种子的发芽率和发芽势,能促使幼苗早出土,并能显著提高幼苗出土后一段时间内的耐寒性与抗病性。幼苗越冬时,雪象一层厚厚的被子覆盖其上,雪内保持着一定的恒温,不至于使幼苗裸露在外,因温度变化太大或风吹沙打而发生冻害和风干。尤其
Snow has a stimulating effect on tree seeds because the heavy water content in snow water is lower than normal water and the nitride content is higher than ordinary water, while high levels of heavy water are detrimental to the metabolism of seeds. At the same time, snow can also absorb ammonia in the atmosphere, ammonia is a large number of plant growth elements needed, so snow can improve the seed germination rate and germination potential, can promote seedling early unearthed, and can significantly improve the seedlings after a period of time Cold resistance and disease resistance. When the seedling is overwintering, the snow is covered with a thick quilt covering it. The snow keeps a constant temperature so that the seedlings will not be exposed and the frost damage and air-drying will occur due to the temperature change or the sand blowing. especially