武夷山不同海拔梯度黄山松土壤有机氮解聚酶活性及其影响因素

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 武夷山不同海拔梯度黄山松土壤有机氮解聚酶活性及其影响因素 DOI: 10.5846/stxb202101210224 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 福建省自然科学基金项目（2019J05163，2020J01397，2020J01142） Soil organic nitrogen depolymerase activities and its influencing factors of Pinus taiwanensis at different altitude gradients in Wuyi Mountain Author: Affiliation: Fund Project: Natural Science Foundation of Fujian Province(2019J05163；2020J01397；2020J01142) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:土壤有机氮（SON）解聚酶对土壤大分子有机氮的解聚是土壤氮循环的限速步骤，对土壤氮循环至关重要。然而，目前亚热带森林中、高海拔梯度下SON解聚酶活性的动态及其影响因素尚不明确。在武夷山自然保护区海拔1200-2000 m的黄山松林，通过测定5个海拔梯度的土壤环境因子、理化性质和8种SON解聚酶活性的变化，探究了不同海拔梯度下SON解聚酶活性的分布规律及其影响因素。结果表明，除土壤DON含量外，其他测量的土壤环境因子和理化性质在不同海拔梯度下均存在显著的差异。SON解聚酶活性随海拔梯度呈现不同的分布规律：碱性蛋白酶（ALPT）、中性蛋白酶（NPT）、漆酶（Lac）和亮氨酸氨基肽酶（LAP）随海拔升高显著增加，酸性蛋白酶（ACPT）和几丁质酶（Chi）呈现先增后降的趋势，而锰过氧化物酶（Mnp）和谷氨酰胺酶（GLS）在海拔1800 m显著降低（P<0.05）。冗余分析表明，不同海拔梯度下SON解聚酶活性存在明显的聚类，土壤环境因子和理化性质对SON解聚酶活性的解释度高达88.18%。土壤温度（ST），含水率（SM），微生物生物量碳（MBC）和矿质氮（NH4+，NO3-）是不同海拔梯度下SON解聚酶活性变化的重要预测因子。相关分析表明，多数SON解聚酶活性与土壤ST呈显著负相关，与pH，SM，TN，MBC，NH4+和NO3-呈显著正相关。NH4+和NO3-含量动态随海拔梯度均呈现波浪式起伏变化，相比于上游的有机质底物，下游无机氮循环中的矿质氮对SON解聚酶活性产生更直接的影响。该研究有助于拓宽我们对亚热带森林中、高海拔土壤氮循环机理的认识，同时对土壤有效氮保持和生产力的维持具有重要意义。 Abstract:The depolymerization of soil organic nitrogen (SON) depolymerases on soil macromolecule organic nitrogen is the rate-limiting step of the soil nitrogen cycle, which plays a crucial role in the soil nitrogen cycle. However, the dynamics of SON depolymerase activities and their influencing factors in subtropical forests at middle and high altitudes are still unclear. In this study, the soil environmental factors, physicochemical properties and the activities of eight kinds of SON depolymerases were measured in the Pinus taiwanensis forest at the altitude of 1200-2000 m in Wuyishan Nature Reserve, and we investigated the distribution of SON depolymerase activities and their influencing factors at different altitude gradients. The results showed that the significant differences were found in all soil environmental factors and physicochemical properties measured at different altitudes except DON content. The activities of SON depolymerase displayed different distribution patterns with altitude gradient:alkaline protease (ALPT), neutral protease (NPT), laccase (Lac) and leucine aminopeptidase (LAP) increased significantly with altitude, and acid protease (ACPT), chitinase (Chi) exhibited a trend of increasing first and then decreasing, while manganese peroxidase (Mnp) and glutaminase (GLS) decreased significantly at altitude of 1800 m. Redundancy analysis showed that SON depolymerase activities were obviously clustered at different altitudes, and the explanation degree of soil environmental factors and physicochemical properties to them was as high as 88.18%. Soil temperature (ST), soil moisture (SM), microbial biomass carbon (MBC), and mineral nitrogen (NH4+, NO3-) are important predictors of SON depolymerase activities at different altitudes. Correlation analysis showed that most of SON depolymerase activities were negatively correlated with soil ST, while positively correlated with pH, SM, TN, MBC, NH4+ and NO3-. The dynamics of NH4+ and NO3- showed a wave-like fluctuation with altitude gradient. Compared with the upstream organic substrate, the mineral nitrogen in the downstream inorganic nitrogen cycle had a more direct impact on SON depolymerase activities. This study is helpful to broaden our understanding of the mechanism of soil nitrogen cycle in subtropical forests at middle and high altitudes, and is of great significance to the protection of soil available nitrogen and the maintenance of soil productivity. 参考文献 相似文献 引证文献