耐盐保水剂对滨海沙地厚荚相思生理和成活率的影响

针对滨海沙地常年风大、地表水分蒸发量大等恶劣的造林环境,研究耐盐保水剂对滨海沙地厚荚相思生长生理和成活率的影响,为保水剂用于滨海沙地造林提供理论依据和技术支持。结果表明：保水剂水凝胶使用量在1 000-2 000 g/株时,不会显著改善厚荚相思的生长生理指标;当使用量为3 000-4 000 g/株时,土壤能够重复多次吸收、贮藏较多的雨水,从而长时间保持较多的水分,供苗木在无雨的干旱时间利用,延缓旱情,并能够显著提高苗木叶片水势、叶片含水量、叶绿素含量,保持根系活力、根系过氧化物酶（POD）活性的相对稳定,减轻干旱对造林苗木的胁迫;与对照相比,苗木的树高、胸径、树冠分别提高0.52-0.74 m,0.6-0.8 cm和15-25 cm,造林成活率和保存率分别提高26.9%-32.2%和20.1%-36.5%。

Effects of salt-resisting water retentive agent on physiology and survival rate of Acacia crassicarpa in coastal sandy soil

The effects of salt-resisting water retentive agent on growth physiology and survival rate of Acacia crassicarpa in coastal sandy soil were studied.The results showed that it had no significant effects on physiological indexes when 1 000-2 000 g salt-resisting water retentive agent to each seedling was used.However,when 3 000-4 000 g salt-resisting water retentive agent to each seedling was used,enough rainwater could be absorbed and stored by soil.So more rainwater would be supplied for seedling during drought period,which would decrease drought stress to seedling and it would increase the water potential,water content and chlorophyll content of leaves.In addition,it would keep root vigor and maintain the root peroxidase(POD).Compared with CK,the height,DBH and crown width of seedling increased 0.52-0.74 m,0.6-0.8 cm and 15-25 cm,respectively.The survival rate and preserving rate increased 26.9%-32.2% and 20.1%-36.5%,respectively.