Studies on the nutrition and fertilizings of trees. (Part 2) : On the determinations of Cation-exchange capacites and ultimate PH in seedling roots of afforestation trees, especiolly in comparisision with other plants

[Author abstract]The cotion exchange capacities (C. E. C) and ultimate pH (pHu) were determined on root of gymnosperms, and the same experiments were practiced to a root of angiosperms. For gymnosperms is used an afforestation plants as Japan cedar, Japan cypress, Japan red pine and Japan black pine, and on the angiosperms is choosed a diffent plant species to dicotyledon and monocotyledon. The C. E. C. of roots on afforestation plants show to range between 21.03 and 24.54 meq. for 100 g. oven dry matter of roots, and its pHu are recorded to range between 3.4 and 3.6. In general, the C. E. C. value of roots of gymnosperms are much higher than for angiosperms, and the root C. E. C. value of dicotyledons are indied a slightly high tendency to compaed with its monocotyledons. Moreover, the relations between C. E. C. and pHu on fresh excised roots were Considered. Generally, for a given weight of H' roots, there is a tendency for the pHu to be lower when the C. E. C. is high and to increase with decreasing C. E. C.[摘要]杉、桧、赤松、黒松等の植林用植物について根(Root colloid)のカチオン置換容量とその究極pHを検した。又被子植物に属する野生の永年生植物と一年生作物についても同様の測定をおこなった｡根のカチオン置換容量は植物のSpeciesにより又生育状態(一年生、永年生等)によって相違するが造林用樹木においては根の乾物100g当りのカチオン置換容量は21.03-24.54meq.でまたその究極pHは3.4-3.6であった。なお杉、桧、赤松、黒松等の裸子植物の根のカチオン置換容量は披子植物に比較して一般に大きい値を示し又被 F植物につき双子葉植物と単子葉植物を比較すると前者における根のカチオン置換容量は後者に比して一般に大なる傾向がみとめられる｡又根のカチオン置換容量と究極pHの関係については、一般に置換容量の減少は究極pHを増加せしめ、カチオン置換容量が高くなると究極pHは低下する傾向がみとめられた