武夷山甜槠群落的钾、钠累积和循环

Accumulation and Biological Cycle of K and Na Elements in Castanopsis eyrei Community in Wuyi Mountains

是武夷山森林生态系统研究的一部分，主要讨论５１年生甜槠［Ｃａｓｔａｎｏｐｓｉｓｅｙｒｅｉ（Ｃｈａｍｐ．ｅｘＢｅｎｔｈ．）Ｔｕｔｃｈ．］群落的钾、钠元素的累积和循环．结果表明：甜槠群落的现存量中，含有的钾、钠总量分别为８２．９３６ｇ／ｍ２和３．５１２ｇ／ｍ２，其中地上部分别为６６．７１０ｇ／ｍ２（占总库存量的８０．４４％）和２．９５２ｇ／ｍ２（占８４．０５％）；地下部分别为１６．２２６ｇ／ｍ２（占１９．５６％）和０．５６０ｇ／ｍ２（占１５．９５％）；各组分的库存量均是Ｋ＞Ｎａ．该群落钾、钠的生物循环中，钾、钠的年吸收量分别为４．６０１ｇ／ｍ２·ａ和０．１７８ｇ／ｍ２·ａ；其中年存留量分别为２．９８９ｇ／ｍ２·ａ和０．０９２ｇ／ｍ２·ａ，而年归还量分别为１．６１２ｇ／ｍ２·ａ和０．０８６ｇ／ｍ２·ａ．甜槠群落钾的周转期６５年，钠６２年，钾元素周转比钠元素慢．５１龄甜群槠落钾、钠的富集率分别为１．５１５和１．２２２，均大于１，说明了５１龄甜槠群落中钾、钠仍在不断地吸收累积．

This paper deals mainly with the accumulation and biological cycle of K and Na elements of 51 year old Castanopsis eyrei community at Xianfengling in Wuyi Mountains.The main results of the measurement were as follows:1)The amounts of K and Na in the standing crop of this community were 82.936 g/m 2 and 3.512 g/m 2,in which the amounts of the two elements in the biomass of aboveground were 66.710 g/m 2 for K and 2.952 g/m 2 for Na,and in the biomass of underground were 16.226 g/m 2 for K and 0.560 g/m 2 for Na,respectively. 2)In biological cycle of K and Na of this stand ,the annual values of the vegetation mineral uptak were 4.601 g/m 2·a for K and 0.178 g/m 2·a for Na,of its retention were 1.612 g/m 2·a for K and 0.086 g/m 2·a for Na. respectively. 3)The turnover periods of K and Na were 65 and 62 years respectively.