不同沙土配比对盆栽平邑甜茶的生长及~(15)N吸收、利用和损失的影响

以当年生盆栽平邑甜茶为试材,应用15↑N同位素示踪技术研究不同沙土配比（不加沙、沙/（沙＋土）=20%、40%、60%、80%、纯沙）对植株的生长及15↑N吸收、利用和损失的影响。结果表明：不同的沙土配比处理,平邑甜茶植株具有不同的生长状况及氮素吸收、利用和损失。沙土配比20%处理的植株生长量（株高、茎粗和总干重）最大（37.54 cm,3.457 mm和16.20 g）,60%处理的全氮和15↑N吸收量最大,分别为189.31,32.39 mg,20%～60%处理下的生长量与氮素吸收、利用要显著高于不加沙和高沙处理（沙土配比〉60%）。各处理的Ndff值和15↑N分配率均为地上部〉地下部,20%～80%处理的植株各部分Ndff值随沙土配比的增大而增大。土壤中15↑N残留量与土壤沙土配比大小呈负相关,随着沙土配比增大,氮素总损失呈现增大的趋势。平邑甜茶植株生长和养分吸收、利用与土壤质地密切相关,适宜的沙土配比有利于植株的生长和氮素吸收、利用,较高的沙土配比加剧了土壤氮素损失。

Effects of Different Sand/Soil Ratio on Growth and ~(15)N Absorption,Utilization and Loss of Potted Malus hupenhensis

One-year-old Malus hupehensis grown in a pot were used in the present study to explore the effects of different sand/soil ratio(clay with no sand,sand/soil ratio=20%,40%,60%,80%,pure-sand)on growth and 15 N absorption,utilization,and loss using 15N trace technique.Results showed that there were different values of plant growth,15N absorption and utilization under different treatments.The value of plant growth(height,stem diameter and total dry weight)was highest(37.54 cm,3.457 mm and 30.46 g) under 20% trea...