<正>运用定位研究法采集位于浙江富阳路西林区垦复与未垦复毛竹（Phyllostachys edulis）纯林枯落物样品（2002~2003年），对其枯落物的量进行比较。结果表明：不论夏季或冬季，未垦复毛竹林枯落物烘干重量均显著高于垦复毛竹林，未垦复毛竹林冬季枯落物烘干重量是垦复毛竹林的1.65～5.74倍。不同毛竹林枯落物养分呈现相似的变化特征，即垦复毛竹林枯落物养分含量和贮量由高到低序列为：Ca、K、Mg、N、P，养分含量0.16～3.3 g/kg，养分贮量0.20～4.50 kg/hm2；未垦复毛竹林相应序列是Ca、K、N、Mg、P，养分含量0.20～5.10 g/kg，养分贮量0.70~29.10 kg/hm~。毛竹林垦复之后由于林地表层的枯落物数量大为减少，枯落物养分贮量也显著低于未垦复毛竹林，因而制约潜在肥力的稳定提高，进行土壤管理时应引起注意。

Super absorbent resins with good salt tolerance were synthesized by using solution polymerization of acrylic acid in the presence of a crosslinking agent, a redox initiator and a chelant. The influence of the amount of the crosslinking agent, chelant and redox initiator as well as the neutralized ratio of acrylic acid on the absorption capacity was studied. It was found that the introduction of chelant (ehylenediaminetetraacetic acid) promoted significantly the absorption for the salt solution. The resulted resins showed an absorption capacity of more than 900 g/g for tap water and 190 g/g in case of 0.9% NaC1 solution respectively. It was also demonstrated that the amount of the crosslinking agent and redox initiator influenced to a certain extent the absorption resins for 0.9% NaC1 solution while the neutralized degree of acrylic acid had no significant impact on the absorption capacity.