摘要
对樟子松人工林土壤不同层次中的全磷、速效磷 ,各级无机磷、有机磷的含量及其相关性进行了初步分析。结果表明 ,樟子松人工林土壤中全磷和速效磷含量都很低 (全磷约为0 0 5～ 0 18mg·g-1,表层土壤速效磷为 1 5 0～ 2 2 4mg·kg-1) ,处于我国土壤磷含量的最低水平 ,且速效磷不到全磷的 0 5 % ,有机磷占全磷的 4 0 %～ 80 % ,非蓄闭态无机磷以Ca P为主 ,在各土层中均为Ca P >Fe P >Al P。表层土壤中各种形态磷含量都显著高于下面三层 ,是各种生物、物理、化学过程最活跃的区域 ,并且存在磷酸盐沿着土壤剖面的淋溶。速效磷含量与有机磷、Fe P、Al P显著相关。不同密度和林龄的磷素状况无显著差异。可见 ,影响樟子松人工林土壤磷素有效性的因素很复杂 ,在较短的时间尺度上不同形态无机磷的相互转化及其影响因素对整个系统的磷素循环起主要作用 ,Fe P、Al P可能是沙地樟子松人工林土壤速效磷的主要来源 ,而有机磷则是重要的潜在有效磷源。
Concentrations and availability of different forms of soil phosphorus (P) in soil profile in Pinus sylvestris var.mongolica plantation were tested.Meanwhile,correlations between different forms of soil P were analyzed.The results indicated that concentrations of soil total P (0.05～0.18 mg·g -1) and olsen-P (1.50～2.24 mg·kg -1in surface soil) were very low,organic P accounted for 40%～80% of total P,and within inorganic P,Ca-P>Fe-P>Al-P.Concentrations of a total P,organic P and fractionas of inorganic P in the 0～5 cm horizon were significantly higher than those in deeper soil horizons.Additionally,phosphate leaching occured along soil profile.Olsen-P was significantly correlated with organic P,Fe-P,and Al-P. In conclusion,factors controlling soil P availability in our study sites were complex.Most probably,the transformation of different forms of inorganic P,especially Fe-P and Al-P,was the main factor influencing the availability of soil P at the short time scale,while organic P was the most important potential of available P.
出处
《生态学杂志》
CAS
CSCD
北大核心
2004年第5期224-227,共4页
Chinese Journal of Ecology
基金
中国科学院知识创新工程重要方向项目(KZCX3-SW-418)
国家科技攻关计划项目(2002BA517A11-5)
中国科学院沈阳应用生态研究所前沿领域资助项目(SLYQY0409)
关键词
樟子松人工林
土壤磷库
无机磷分级
有效性
Pinus sylvestris var.mongolica plantation,soil phosphorus pool,phosphorus contents,availability.
