scholarly journals Interactive effects of global change factors on soil respiration and its components: a meta-analysis

2016 ◽  
Vol 22 (9) ◽  
pp. 3157-3169 ◽  
Author(s):  
Lingyan Zhou ◽  
Xuhui Zhou ◽  
Junjiong Shao ◽  
Yuanyuan Nie ◽  
Yanghui He ◽  
...  
Keyword(s):  
Global Change ◽  
Soil Respiration ◽  
Meta Analysis ◽  
Interactive Effects ◽  
Change Factors

Soil respiration and its components respond asymmetrically to throughfall reduction and nitrogen additions in a subtropical Moso bamboo forest in the Southwest China

2020 ◽  
Author(s):  
Yi Wang ◽  
Shirong Liu ◽  
Junwei Luan
Keyword(s):  
Global Change ◽  
Soil Respiration ◽  
Southwest China ◽  
Fine Root ◽  
Global Climate ◽  
Moso Bamboo ◽  
Change Factors ◽  
The Impact ◽  
Throughfall Reduction ◽  
Nitrogen Additions

<p>The roles of multiple global change are expected for many terrestrial ecosystems in future. As two main global change factors, the impact of drought and nitrogen deposition and their interaction on soil respiration and its components (R) remains unclear. To explore the responses of soil respiration (R<sub>s</sub>), autotrophic respiration (R<sub>a</sub>) and heterotrophic respiration (R<sub>h</sub>) to multiple global change factors, we established a field experiment of throughfall reduction and nitrogen additions in a subtropical Moso bamboo (<em>Phyllostachys heterocycla</em>) forest in the Southwest China, using a 4 × 4 completely randomized design. Results showed that bivariate exponential equation with soil temperature (T) and soil moisture (SWC) (R=a.e<sup>bT</sup>.SWC<sup>c</sup>) was fitted to predict R<sub>s</sub>, R<sub>a</sub> and R<sub>h</sub>. Throughfall reduction, nitrogen additions and their interaction had no effect on annual mean R<sub>s</sub> and R<sub>a</sub>, but nitrogen additions significantly depressed annual mean R<sub>h</sub>. Nitrogen additions significantly decreased contribution of R<sub>h</sub> to R<sub>s</sub> and increased contribution of R<sub>a</sub> to R<sub>s</sub>, however, the contributions were non-responsive under throughfall reduction. The more positive effect of nitrogen additions on the contribution of R<sub>a</sub> to R<sub>s</sub> was appeared compared with that of throughfall reduction, thereby more negative effect on the contribution of R<sub>h</sub> to R<sub>s</sub>. The fine root biomass, fine root carbon and nitrogen storage regulated R<sub>s</sub>, while fine root phosphorus storage determined R<sub>a</sub>. The R<sub>h</sub> was negatively correlated with vector lengths, thus suggesting that microbial carbon limitation caused the decline of R<sub>h</sub>. Our findings demonstrate that the nitrogen additions played overriding role than throughfall reduction in affecting the contribution of R<sub>a</sub> and R<sub>h</sub> to R<sub>s</sub>. Moreover, the negative response of temperature sensitivity of R<sub>s</sub> and R<sub>h</sub> to nitrogen additions, suggesting that that the nitrogen additions may weaken the positive response of soil CO<sub>2</sub> emission to global climate warming. Our study highlights asymmetrical responses of R<sub>s</sub>, R<sub>a</sub> and R<sub>h </sub>to throughfall reduction and nitrogen additions and could enhance accurate predictions of soil carbon dynamics in response to multiple global climate change in future.</p>

scholarly journals Global change factors influence different aspects of arbuscular mycorrhizal fungal communities

2021 ◽  
Author(s):  
Junqiang Zheng ◽  
Mingming Cui ◽  
Cong Wang ◽  
Jian Wang ◽  
Shilin Wang ◽  
...  
Keyword(s):  
Global Change ◽  
Variable Selection ◽  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizal ◽  
Dispersal Limitation ◽  
Interactive Effects ◽  
N Addition ◽  
Change Factors ◽  
Α Diversity ◽  
Amf Communities

Abstract BackgroundThe functional diversity of arbuscular mycorrhizal fungi ( AMF) affects the resistance and resilience of plant communities to environmental stresses. However, considerable uncertainty remains about how the complex interactions among elevated atmospheric CO 2 (eCO 2 ), nitrogen deposition (eN), increased precipitation (eP), and warming (eT) affect AMF communities. These global change factors (GCFs) always occur simultaneously, and their interactions likely affect AMF community structure and assembly processes. In this study, the interactive effects of these four GCFs on AMF communities were explored in an open-top chamber field experiment in a semiarid grassland. ResultsElevated CO 2 , eN, eT, and eP and their interactions did not affect AM fungal biomass. The relative abundance of Paraglomus increased with N addition across treatment combinations, whereas that of Glomus decreased with N addition, especially combined with eT and eCO 2 . Precipitation, T, and N affected AMF phylogenetic α-diversity, and the three-way interaction among CO 2 , T, and N affected taxonomic and phylogenetic α-diversity. Nitrogen addition significantly affected the β-diversity of AMF communities. Both variable selection and dispersal limitation played major roles in shaping AMF communities, whereas homogeneous selection and homogenizing dispersal had almost no influence on AMF community assembly. The contribution of variable selection decreased under eCO 2 , eN and eT, but not under eP. The contribution of dispersal limitation decreased under eCO 2 , eT, and eP but it increased under eN. The assembly of AMF communities under the sixteen GCF combinations was strongly influenced by dispersal limitation, variable selection and ecological drift. ConclusionsElevated CO 2 , warming, N addition, and increased precipitation influenced different aspects of AMF communities. The interactive effects of the four GCFs on AMF communities were limited. Collectively, the results of this study suggest that AMF communities in semiarid grasslands can resist changes in the global climate.

Sign in / Sign up

Export Citation Format

Share Document