CAJ | 학술논문

土壤养分影响植物生长,进而影响凋落物质量和产量;凋落物质量和产量影响凋落物分解过程.基于一个生长实验和一个相同环境分解实验,研究了冬小麦(Triticum aestivum)生境中养分可利用性对凋落物碳(C)和氮(N)释放的影响.结果显示:(1)冬小麦凋落物产量、叶/根C:N比、C释放量和N释放量随土壤养分梯度呈单调变化;(2)土壤养分影响叶凋落物丢失率而不影响根凋落物丢失率;(3)初始叶/根C:N比与其C、N释放量之间存在负相关关系;(4)分解过程降低叶C:N比和根C:N比.结果表明:生境中土壤养分的提高可加速凋落物C、N归还,这反过来可能促进冬小麦生长,因此这种效应是正反馈;初始C:N比可预测凋落物C、N释放量.
토양양분영향식물생장,진이영향조락물질량화산량;조락물질량화산량영향조락물분해과정.기우일개생장실험화일개상동배경분해실험,연구료동소맥(Triticum aestivum)생경중양분가이용성대조락물탄(C)화담(N)석방적영향.결과현시:(1)동소맥조락물산량、협/근C:N비、C석방량화N석방량수토양양분제도정단조변화;(2)토양양분영향협조락물주실솔이불영향근조락물주실솔;(3)초시협/근C:N비여기C、N석방량지간존재부상관관계;(4)분해과정강저협C:N비화근C:N비.결과표명:생경중토양양분적제고가가속조락물C、N귀환,저반과래가능촉진동소맥생장,인차저충효응시정반궤;초시C:N비가예측조락물C、N석방량.
Aims Our objective is to test whether C and N releases in winter wheat (Triticum aestivum) litter change mono-tonically or unimodally with soil nutrients in its habitats.Methods We conducted a growth experiment where winter wheat was subjected to 6-level nutrient regimes and a common garden decomposition experiment. We determined initial C:N ratios of live tissues, biomass loss of litters, C:N ratios of remaining litter, and the amounts of C and N releases. We analyzed correlations between ini-tial C:N ratios and C/N release or between C:N ratios. All data were analyzed with SPSS 13.0 and R 2.9.1.Important findings Litterfall, initial leaf/root C:N ratios, C:N ratios of remaining litter, and C and N releases changed monotonically along a soil nutrient gradient. Soil nutrients had significant effects on biomass loss of leaves, but not of roots. There were negative correlations between initial leaf/root C:N ratios and C and N releases. Initial leaf/root C:N ratios were strongly and positively correlated with C:N ratios of remaining litter. These find-ings suggest that (1) increased soil nutrients surrounding winter wheat plants enhance C and N return in litter, thereby being beneficial to its growth, (2) C:N ratios indicate the potential amounts of C and N releases, and (3) decomposition processes decrease C:N ratios in remaining litter.