辽东山区次生林生态系统主要林型穿透雨的理化性质

2008年7-9月，测定了辽东山区次生林生态系统5种主要林型（落叶松人工林、花曲柳林、杂木林、红松人工林和蒙古栎林）中穿透雨和林外雨的理化性质.结果表明：与林外雨相比，5种林型穿透雨均出现明显的酸化(P＜0.05)，其酸化程度为：红松林＞落叶松林＞杂木林＞蒙古栎林＞花曲柳林；各林型的穿透雨电导率和总溶解固体含量显著升高 (P＜0.05)，为蒙古栎林＞花曲柳林＞落叶松林＞杂木林＞红松林；穿透雨的溶解氧浓度显著降低(P＜0.05)，为红松林＞杂木林＞花曲柳林＞蒙古栎林＞落叶松林；穿透雨中Cl^-浓度较林外雨明显升高，为落叶松林＞蒙古栎林＞杂木林＞花曲柳林＞红松林；花曲柳林、蒙古栎林和杂木林穿透雨中NO₃^-浓度均高于林外雨，而落叶松林和红松林NO₃^-浓度低于林外雨.

Physical and chemical properties of throughfall in main forest types of secondary forest ecosystem in montane regions of eastern Liaoning Province, China

From July to September 2008,a measurement was made on the physical and chemical properties of bulk precipitation and throughfall in five main forest types,i.e.,larch plantation (LP).Fraxinus rhynchophylla stand(FR),mixed forest stand(MF),Korean pine plantation (KP),and Mongolian oak stand(MO),of secondary forest ecosystem in montane regmns of eastern Liaoning Province,China.Comparing with bulk precipitation,the throughfall in the five forest types was significantly acidified(P<0.05),and the acidification degree was in the order of KP> LP>MF>MO>FR.The conductivity and total dissolved solids of the throughfall increased significantly(P<0.05),and were in the sequence of MO>FR>LP>MF>KP.The dissolved oxygen concentration of the throughfall lowered significantly(P<0.05),with the rank of KP>MF>FR>MO>LP,while the Cl~- concentration increased significantly,ranked as LP>MO>MF>FR>KP.The NO_3~- concentrations of the throughfall in FR,MO and MF were higher,while those in LP and KP were lower than that of the bulk precipitation.