Consistent effects of canopy vs. understory nitrogen addition on the soil exchangeable cations and microbial community in two contrasting forests

被引：67

作者：

Shi, Leilei ^{[1
,2
]}

Zhang, Hongzhi ^{[1
,2
]}

Liu, Tao ^{[1
,2
]}

Zhang, Weixin ^{[1
]}

Shao, Yuanhu ^{[1
]}

Ha, Denglong ^{[3
]}

Li, Yuanqiu ^{[4
]}

Zhang, Chuangmao ^{[4
]}

Cai, Xi-an ^{[1
]}

Rao, Xingquan ^{[1
]}

Lin, Yongbiao ^{[1
]}

Zhou, Lixia ^{[1
]}

Zhao, Ping ^{[1
]}

Ye, Qing ^{[1
]}

Zou, Xiaoming ^{[5
]}

Fu, Shenglei ^{[1
]}

机构：

[1] Chinese Acad Sci, Key Lab Vegetat Restorat & Management Degraded Ec, South China Bot Garden, Guangzhou 510650, Guangdong, Peoples R China

[2] Univ Chinese Acad Sci, Beijing 100049, Peoples R China

[3] Jigongshan Natl Nat Reserve, Xinyang 464000, Henan, Peoples R China

[4] Shimentai Natl Nat Reserve, Yingde 513000, Guangdong, Peoples R China

[5] Univ Puerto Rico, Inst Trop Ecosyst Studies, San Juan, PR 00931 USA

来源：

SCIENCE OF THE TOTAL ENVIRONMENT | 2016年 / 553卷

关键词：

N deposition; Canopy addition of N; Understory addition of; MYCORRHIZAL FUNGI; PLANT DIVERSITY; FATTY-ACIDS; DEPOSITION; ACIDIFICATION; NITRATE; IMPACT; CYCLE; METAANALYSIS; RETENTION;

D O I：

10.1016/j.scitotenv.2016.02.100

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

Anthropogenic N deposition has been well documented to cause substantial impacts on he chemical and biological properties of forest soils. In most studies, however, atmospheric N deposition has been simulated by directly adding N u he forest floor. Such studies thus ignored the potentially significant effect of some key processes occurring in forest canopy (i.e., nitrogen retention) and may therefore have incorrectly assessed the effects of N deposition on soils. Here, we conducted an experiment that included both understory addition of N (UAN) and canopy addition of N (CAN) in two contrasting forests (temperate deciduous forest vs. subtropical evergreen forest). The goal was to determine whether the effects on soil exchangeable cations and microbial biomass differed between CAN and UAN. We found that N addition reduced pH, BS (base saturation) and exchangeable Ca and increased exchangeable Al significantly only at the temperate JGS site, and reduced the biomass of most soil microbial groups only at the subtropical SMT site. Except for soil exchangeable Mn, however, effects on soil chemical properties and soil microbial community did not significantly differ between CAN and UAN. Although biotic and abiotic soil characteristics differ significantly and the responses of both soil exchangeable cations and microbial biomass were different between the two study sites, we found no significant interactive effects between study site and N treatment approach on almost all soil properties involved in this study. In addition, N addition rate (25 vs. 50 kg N ha(-1) yr(-1)) did not show different effects on soil properties under both N addition approaches. These findings did not support previous prediction which expected that, by bypassing canopy effects (i.e., canopy retention and foliage fertilization), understory addition of N would overestimate the effects of N deposition on forest soil properties, at least for short time scale. (C) 2016 Elsevier B.V. All rights reserved.

引用

页码：349 / 357

页数：9

共 63 条

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