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以四季竹纯林为对象,研究了4种密度(D1:24600～29800株·hm-2;D2:37500～42600株·hm-2;D3:46500～52800株·hm-2;D4:76500～85500株·hm-2)下1～3年生立竹的成熟叶和凋萎叶的C、N、P化学计量特征及养分重吸收规律.结果表明:随竹林密度的增大,成熟叶C、N、P含量和凋萎叶C、P含量总体下降,凋萎叶N含量先升高后降低,D4密度时成熟叶C含量急剧下降;叶片C/N和C/P呈升高趋势,N/P先升高后降低.D3、D4密度的叶片N、P养分利用效率显著高于D1、D2密度;叶片N、P重吸收率分别呈先降后升和持续升高的趋势.D1～D3密度的成熟叶N/P为16.24～19.37,四季竹生长受P的限制,促进叶片建成,种群生长旺盛.D4密度的成熟叶N/P为13.42～15.74,N限制作用增强,叶片凋萎脱落,种群生长受到抑制.四季竹通过调节叶片的C、N、P含量及其化学计量比,提高了N、P利用效率及重吸收能力,以适应高密度下环境资源的激烈竞争.在本试验条件下,D3密度是四季竹适宜的经营密度.
Four species of pure bamboo were used as experimental materials. Four kinds of density (D1: 24600 ~ 29800 plants · hm-2; D2: 37500 ~ 42600 plants · hm-2; D3: 46500 ~ 52800 plants · hm-2; ~ 85500 plant · hm-2), the C, N, P stoichiometry and nutrient reabsorption of mature and wilted leaves from 1 to 3 years old were studied.The results showed that with the increase of density of bamboo, , N and P content and C and P content in wilting leaves decreased. N content in wilting leaf increased first and then decreased, and C content in mature leaf declined sharply at D4 densities. C / N and C / P of leaves increased, N / P firstly increased and then decreased, N and P nutrient utilization efficiency in leaves at D3 and D4 density was significantly higher than that at D1 and D2, N and P resorption rates in leaves at first, ~ D3 density of mature leaves N / P was 16.24 ~ 19.37, the growth of the four seasons bamboo was limited by P, promote leaf formation, strong population growth.D4 density of mature leaves N / P 13.42 ~ 15.74, N limit enhanced, leaf withered The loss of wilt and the suppression of population growth.Siger bamboo by adjusting the leaf C, N, P content and stoichiometry, improve the N, P utilization efficiency and reabsorption capacity in order to adapt to the intense competition of high-density environment resources. this Under the test conditions, D3 density is the appropriate operating density of the four seasons bamboo.