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土壤动物对高寒森林凋落物养分元素动态具有重要影响,但这种影响受控于凋落物质量及环境条件。为了解土壤动物对高寒森林凋落物不同分解时期凋落物中N和P元素动态的影响,采用凋落物分解袋的方法,于凋落物第一年分解的不同时期,即冻结前期、冻结期、融化期、生长季节初期、生长季节中期和生长季节末期,研究了3.00和0.04 mm孔径凋落物袋中川西亚高山和高山森林的代表性植物——康定柳(Salix paraplesia)、方枝柏(Sabina saltuaria)、红桦(Betula albosinensis)和岷江冷杉(Abies fargesii var.faxoniana)凋落物中的N和P元素动态特征。结果表明:康定柳和红桦凋落物中的N元素呈现出释放—富集—释放的模式,方枝柏、岷江冷杉凋落物中的N元素则表现为释放—富集模式;凋落物P元素总体表现为释放模式,但4种植物凋落物均在生长季节中期具有明显的富集过程;从凋落物分解的第一年来看,土壤动物明显促进了4种植物凋落物N的释放,而抑制了P的释放;不同时期土壤动物对凋落物中N和P释放量的影响存在显著差异,且分别与正积温呈极显著正相关和极显著负相关关系;相对于阔叶植物凋落物,土壤动物对针叶植物凋落物中N和P元素动态的影响更为显著。这些结果为深入了解高寒森林生态系统土壤动物与凋落物分解等物质循环过程的相互联系具有重要意义。
Soil fauna has an important impact on nutrient elements in litter in alpine forests, but this effect is controlled by litter quality and environmental conditions. In order to understand the effects of soil fauna on the dynamics of N and P elements in litter at different decomposition stages of alpine forest litter, litter decomposition bags were used to study the effects of litter decomposition on the dynamics of litter decomposition in different periods of first year, Salix paraplesia, Sabina saltuaria, a representative plant in the 3.00 and 0.04 mm bore litter bags in the western Sichuan alpine and alpine forests, were studied in the period, early growing season, mid-growing season and late season. , Betula albosinensis and Abies fargesii var. Faxoniana litters. The results showed that the N element in the litter of Kangding and Betula platyphylla showed a pattern of release-enrichment-release. The N element in the litter of Fagus incana and Abies faxoniana showed a pattern of release-enrichment, However, all four plant litters showed significant enrichment during mid-season of growing season. From the first year of litter decomposition, soil animals significantly promoted the release of four plant litter N and inhibited The release of P. The soil animals had significant differences in the release of N and P from the litter in different periods and showed extremely significant positive and negative correlations with the positive accumulated temperature respectively. Compared with the broad-leaved litter and soil The effects of animals on the dynamics of N and P elements in the litter of coniferous plants were more significant. These results are of great significance for understanding the interrelation between soil animal and litter decomposition and other material cycles in the alpine forest ecosystem.