黄土丘陵区生态治理对土壤碳氮磷及其化学计量特征的影响

发布时间：2018-08-09 17:40

【摘要】：为了探究不同生态治理措施对土壤碳(C)、氮(N)、磷(P)含量及其化学计量特征的影响,为黄土丘陵区的生态治理与植被恢复提供科学依据,以黄土丘陵区典型小流域王茂沟为例,通过野外采样与室内分析相结合的方法,对研究区坡耕地、林地、草地、灌木地及梯田等5个样地0—100cm土壤样品的C、N、P及其化学计量比进行了分析研究。结果表明:(1)坡耕地经过生态治理转变为林地、草地、灌木地及梯田等生态用地,土壤C、N含量分别提高了1.27,1.18,1.24,1.14倍及1.64,1.64,1.76,1.57倍;土壤C和N呈极显著的正相关关系;在0—100cm土层,林地、草地、灌木地及梯田的土壤C、N分布规律一致,均随土壤深度增加而减小,且在0—20cm土层出现了富集现象,而土壤P含量分布比较均匀;(2)坡耕地C∶N均值显著大于其他样地(P0.05),在0—20cm土层,土壤C∶P与N∶P表现为林地、草地、灌木地及梯田显著高于坡耕地(P0.05);土壤C∶N随着土层深度的变化不显著,C∶P与N∶P随土层加深呈减小的趋势;(3)土壤C、N、P化学计量比的分布主要由土壤C、N决定;土壤C∶P、N∶P与土壤中铵态氮、粘粒、砂粒、水稳性大团聚体含量之间的相关性均通过了显著性检验(P0.05)。土壤C、N、P及其化学计量比不仅受生态治理和土层深度的影响,还与土壤理化性质相关,土壤C∶N、C∶P、N∶P可以指示土壤的肥力状况。
[Abstract]:In order to explore the effects of different ecological control measures on soil carbon, (C), nitrogen, (N), phosphorus and (P) contents and their stoichiometric characteristics, and to provide scientific basis for ecological management and vegetation restoration in loess hilly areas, a typical small watershed Wang Mao gully in loess hilly region was taken as an example. Based on the method of field sampling and indoor analysis, the 0-100cm soil samples and their stoichiometric ratios of five plots in the study area, such as sloping farmland, woodland, grassland, shrub land and terrace, were studied. The results showed that: (1) after ecological treatment, the soil C ~ + N content of sloping farmland changed into forest land, grassland, shrub land and terrace, the content of C ~ + N in soil increased 1.27 ~ 1.18 ~ 1.24 ~ 1.14 times and 1.64 ~ 1.64 ~ 1.76 ~ 1.57 times respectively, the correlation between soil C and N was very significant, and in 0-100cm soil layer, forest land. The distribution of Con N in grassland, shrub land and terrace was the same, which decreased with the increase of soil depth, and was enriched in 0-20cm soil layer. (2) the average value of C _ (1) N in sloping farmland was significantly higher than that in other plots (P0.05). In 0-20cm soil layer, soil C _ (1) P and N _ (1) P were forest land and grassland. Shrub land and terrace were significantly higher than sloping farmland (P0.05), soil C _ (1) N was not significantly changed with the depth of soil layer, C _ (10) P and N _ (7) P decreased with the deepening of soil layer, (3) the distribution of soil C _ (10) N _ (N) stoichiometric ratio was mainly determined by soil C ~ (2 +). The correlation between the content of ammonium nitrogen, clay, sand and water stable aggregates in soil C: Pn: P passed the significant test (P0.05). Soil C N N P and its stoichiometric ratio were not only affected by ecological treatment and soil depth, but also related to soil physical and chemical properties.
【作者单位】：西安理工大学西北旱区生态水利工程国家重点实验室培育基地;
【基金】：国家自然科学基金重点项目“黄土高原生态建设的生态—水文过程响应机理研究”(41330858);国家自然科学基金项目“基于能量过程的坡沟系统侵蚀产沙过程调控与模拟”(41471226) 陕西省青年科技新星计划项目(2016KJXX-68)
【分类号】：S153.6

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