干旱区生态环境知识资源中心(Arid): 岷江上游干旱河谷优势灌丛群落土壤生态酶化学计量特征

Arid

	岷江上游干旱河谷优势灌丛群落土壤生态酶化学计量特征
其他题名	Patterns of ecoenzymatic stoichiometry in the dominant shrubs in the semi-arid Upper Minjiang River Valley
	王冰冰 1; 曲来叶 1; 马克明 1; 张心昱 2; 宋成军 3
来源期刊	生态学报
ISSN	1000-0933
出版年	2015
卷号	35 期号:18 页码:6078-6088
中文摘要	与碳(C)、氮(N)和磷(P)分解矿化相关的土壤生态酶的相对活性可以揭示微生物生长和代谢过程的能量限制。尽管干旱生态系统愈来愈受到生态学家的关注,但在土壤水分有效性限制和斑块状分布的植被背景下,探讨土壤酶活性化学计量特征,及其与土壤物理、化学因子和土壤微生物群落结构的关系的相关研究仍十分缺乏。通过调查岷江干旱河谷不同水分梯度4个研究样地(两河口、飞虹、撮箕和牟托)灌丛及其丛间空地的土壤物理化学性质、微生物群落组成和土壤生态酶活性,探讨不同水分梯度样地间及灌丛和空地间土壤酶活性计量的分布特征。结果显示,岷江干旱河谷土壤С:N:P酶活性化学计量表现出了与全球尺度上酶活性化学计量的相对特异性(С:N:P=3:2:2vs.1:1:1)。整体上,岷江干旱河谷区域土壤微生物生长代谢存在一定程度的N限制。虽然酶活性化学计量特征在所有空地和灌丛土壤之间总体未表现出显著差异,但对各研究地的进一步分析表明,两个相对干旱的两河口和飞虹样地表现出更为明显的N限制,而两个相对湿润的撮箕和牟托样地则存在一定的P限制。这种样地间的差异性主要受土壤水分有效性的驱动。逐步回归分析表明,土壤含水量是不同样地间土壤С:N酶活性比(ln(BG):ln(NAG+LAP))和N:P酶活性比(ln(NAG+LAP):ln(AP))的决定性影响因子。而土壤含水量与С:N酶活性比具有显著正相关关系,与N:P酶活性比表现为显著负相关关系。此外,土壤真菌、菌根真菌和真菌:细菌比对土壤酶活性化学计量的影响,说明了真菌和菌根真菌类群对干旱河谷养分循环的重要作用。
英文摘要	The activities of soil ecoenzymes in relation to the mineralization of soil organic carbon, nitrogen, and phosphorus can reveal stoichiometric and energy limitations on the growth and metabolism of soil microbes. Despite the fact that arid and semi-arid ecosystems have received considerable attention in recent years, studies on the patterns of soil ecoenzymatic stoichiometry and the relationships among soil physiochemical and microbial community factors are still rare. In this study,we investigated the variations of soil physiochemical properties, microbial community composition, and EEAs by comparing soils in dominant shrubs and in the shrub-interspaces at four sites (Lianghekou, Feihong, Cuoji, and Moutuo). These study sites were expected to differ with respect to the level of water stress along the semi-arid valley in the upper Minjiang River, Sichuan province. The patterns of ecoenzymatic stoichiometry of С:N:P were different in the semi-arid Minjiang River valley as compared to those in the global pattern (C:N:P = 3:2:2 vs. 1:1:1). Overall, there may be some degree of nitrogen limitation of microbial metabolism in this semi-arid region,which was supported by the relative activities of beta-glucosidase compared to beta-N-acetylglucosaminidase + leucine aminopeptidase and beta-N-acetylglucosaminidase + leucine aminopeptidase to phosphatase. The different patterns of enzymatic stoichiometry between the soils in shrubs and in the shrub interspaces were not obvious. However, the limitation of C, N, and P resources in each individual site was somewhat site specific and may be due to the soil water availability. The two relatively drier sites (Lianghekou and Feihong) were more constrained by nitrogen availability, while:he two relatively wetter sites (Cuoji and Moutuo) were more constrained by phosphorus availability. The variations of soil enzymatic stoichiometric patterns were affected by nutrient availabilities and soil water content as shown by the Pearson product-moment correlation analysis. The results of stepwise regression further revealed that the variations of enzyme ratios, such as С:N and N:P, were driven primarily by soil water content. Soil water content was positively correlated with the С:N enzyme ratio and negatively correlated with the N:P enzyme ratio. We also observed that arbuscular mycorrhizal fungi (AMF) and the fungi-to-bacteria ratio positively correlated with the С:N enzyme ratio, but negatively with the N: P enzyme ratio, which may imply that the enrichment of fungi and AMF communities will benefit С and P cycling by influencing enzyme activities. Our results suggest that any predicted decrease in soil water with climate change will probably further constrain the availability of N and P in this N-limited ecosystem in the semi-arid region. Moreover,this study also highlights the important role of fungi and AMF communities in meditating С and P cycling in this semi-arid region.
中文关键词	岷江 ; 干旱河谷 ; 生态酶化学计量 ; 养分有效性 ; 土壤含水量
英文关键词	Minjiang River semi-arid river valley ecoenzymatic stoichiometry nutrient availability soil water content
语种	中文
国家	中国
收录类别	CSCD
WOS类目	BIOLOGY
WOS研究方向	Life Sciences & Biomedicine - Other Topics
CSCD记录号	CSCD:5522101
来源机构	中国科学院地理科学与资源研究所
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/233201
作者单位	1.中国科学院生态环境研究中心, 城市与区域国家重点实验室, 北京 100085, 中国; 2.中国科学院地理科学与资源研究所, 中国科学院生态系统网络观测与模拟重点实验, 北京 100101, 中国; 3.农业部规划设计研究院, 北京 100125, 中国
推荐引用方式 GB/T 7714	王冰冰,曲来叶,马克明,等. 岷江上游干旱河谷优势灌丛群落土壤生态酶化学计量特征[J]. 中国科学院地理科学与资源研究所,2015,35(18):6078-6088.
APA	王冰冰,曲来叶,马克明,张心昱,&宋成军.(2015).岷江上游干旱河谷优势灌丛群落土壤生态酶化学计量特征.生态学报,35(18),6078-6088.
MLA	王冰冰,et al."岷江上游干旱河谷优势灌丛群落土壤生态酶化学计量特征".生态学报 35.18(2015):6078-6088.