关键词: 陕西, 陕西, 温室, 低温冻害, 损失率, 风险, 加温, 界线

Abstract:

In order to select species which were suitable for being planted in saline land and tidal flat in the southern coast of Zhejiang Province, the author extensively collected and introduced species which had salt tolerance and wind resistance, conducted regional test. The results showed that: soil conditions along the coast were complex, in new reclaimed coastal land, soil salinity increased gradually with depth; 1‰-3‰ salinity of 36 candidate species, 3‰-5‰ salinity of 28 candidate species, 5‰-8‰ salinity of 16 candidate species; Ficus concinna var. subsessilis, Taxodium mucronatum×Cryptomeria fortunei etc. 19 species showed strong wind resistance, with trees grew older, the rate dropped down that trees were blew down by the wind; crown diameter/height ratio of shelterbelt species of different age classes was between 0.45-1.13, Ficus concinna var. subsessilis, Buxus megistophylla, Nerium oleander were the highest, relative crown length values of Nerium oleander, Buxus megistophylla were more, must be planted with other species, and the protective effect could play better; the annual growth rhythm of several high resistance species showed, the order from high to low was: Eucalyptus.Dunnii (1.18 cm/a)＞Casuarina equisetifolia 501 (1.16 cm/a)＞Taxodium mucronatum×Cryptomeria fortunei (1.08 cm/a)＞Ficus concinna var. subsessili (1.07 cm/a)＞Sapium sebiferum s (0.92 cm/a). And the diameter growth rate was: Ficus concinna var. subsessilI i(1.58 cm/a)＞Eucalyptus.Dunnii (1.35 cm/a)＞Casuarina equisetifolia 501 (1.15 cm/a)＞Taxodium mucronatum×Cryptomeria fortunei (1.06 cm/a)＞Sapium sebiferums (0.93 cm/a). was the minimum, relative crown length values of Nerium oleander, Buxus megistophylla, Rhaphiolepis umbellata were more, must be planted with other species, and the protective effect can play better; the annual growth rhythm of several high resistance species showed, the order from high to low was Casuarina equisetifolia 501＞Eucalyptus.Dunnii＞Taxodium mucronatum ×Cryptomeria fortunei＞Sapium sebiferum＞Ficus concinna var. subsessilis＞Quercus virginiana.