Temporal Precipitation Variation and Leaf Stoichiometric Changes Mediate the Dynamics of Tree Growth Responses to Nitrogen Addition Over Time DOI
Aijun Xing, Haihua Shen, Enzai Du

и другие.

Journal of Geophysical Research Biogeosciences, Год журнала: 2024, Номер 129(10)

Опубликована: Окт. 1, 2024

Abstract Nitrogen (N) addition can stimulate tree growth; however, the strength of this growth effect usually changes over time and factors underlying these responses are not fully understood. Based on a decade‐long N experiment (by adding 0, 20, 50, 100 kg ha −1 yr ) in boreal forest, we studied to explored potential role temporal precipitation variation plant stoichiometric mediating this. We found positive but changed nonlinearly time. Annual was positively related under high‐level addition; hence, hump‐shape pattern contributed nonlinear responses. After effects were accounted for, peaked seventh year then declined for all levels N. Later reductions could partly be attributed increased leaf N:phosphorus (P) ratio time, especially at higher rates. also an increase soil acid phosphatase, labile occluded P fraction, decreased resorption efficiency with increasing rates during late stage experiment, suggesting demand. Collectively, our results imply that nutrient stoichiometry cumulative input may limit stimulation while appears unlikely modulate atmospheric deposition.

Язык: Английский

A new high-resolution multi-drought-index dataset for mainland China DOI Creative Commons
Qi Zhang, Chiyuan Miao, Jiajia Su

и другие.

Earth system science data, Год журнала: 2025, Номер 17(3), С. 837 - 853

Опубликована: Март 5, 2025

Abstract. Drought indices are crucial for assessing and managing water scarcity agricultural risks; however, the lack of a unified data foundation in existing datasets leads to inconsistencies that challenge comparability drought indices. This study is dedicated creating CHM_Drought, an innovative comprehensive long-term meteorological dataset with spatial resolution 0.1° collected from 1961 2022 mainland China. It features six pivotal indices: standardized precipitation index (SPI), evapotranspiration (SPEI), evaporative demand (EDDI), Palmer severity (PDSI), self-calibrating (SC-PDSI), vapor pressure deficit (VPD), which SPI, SPEI, EDDI contain multi-scale periods 2 weeks 1–12 months. The application high-density station complete framework starting basic elements (the China Hydro-Meteorology dataset, CHM). Demonstrating its robustness, excels accurately capturing events across China, as evidenced by detailed depiction summer Yangtze River basin. In addition, evaluate we performed consistency tests calculated based on Climatic Research Unit (CRU) CN05.1 found all had high overall 2-week-scale potential early-warning roles monitoring. Overall, our bridges gap high-precision multi-index CHM-based ensures reliability contributes enhancing understanding patterns trends Free access can be at https://doi.org/10.5281/zenodo.14634773 (Zhang Miao, 2025).

Язык: Английский

Процитировано

0

Climate Variability Modulates the Temporal Stability of Carbon Sequestration by Changing Multiple Facets of Biodiversity in Temperate Forests Across Scales DOI

Jiahui Chen,

Xuetao Qiao, Minhui Hao

и другие.

Global Change Biology, Год журнала: 2025, Номер 31(4)

Опубликована: Апрель 1, 2025

ABSTRACT Climate variability poses a significant threat to ecosystem function and stability. Previous studies suggest that multiple facets of biodiversity enhance the temporal stability forest functioning through compensatory effects. However, as climate change intensifies, two key questions remain unresolved: (1) mechanisms by which different sustain carbon sequestration across spatial scales (2) how influences at scales. In this study, based on data from 262 natural communities in temperate forests northeastern China, we aggregated metacommunities varying extents. Using ordinary‐least squares regression, examined relationships between (hereafter, “stability”) We then employed mixed‐effects models assess influence biotic Additionally, applied piecewise structural equation modeling disentangle among variability, biodiversity, Our findings indicate (taxonomic, functional, phylogenetic diversity) primarily insurance Temperature was negatively correlated with all facets, declines were associated reduced Precipitation contrast, α diversity but positively β facets. Unexpectedly, precipitation exhibited an overall positive correlation These results increasing temperature may pose greater ecosystems future. Thus, preserving will be critical for mitigating adverse effects warming. Furthermore, impact cannot overlooked arid semi‐arid regions. study provides novel insights into conservation under global change.

Язык: Английский

Процитировано

0

Temporal Precipitation Variation and Leaf Stoichiometric Changes Mediate the Dynamics of Tree Growth Responses to Nitrogen Addition Over Time DOI
Aijun Xing, Haihua Shen, Enzai Du

и другие.

Journal of Geophysical Research Biogeosciences, Год журнала: 2024, Номер 129(10)

Опубликована: Окт. 1, 2024

Abstract Nitrogen (N) addition can stimulate tree growth; however, the strength of this growth effect usually changes over time and factors underlying these responses are not fully understood. Based on a decade‐long N experiment (by adding 0, 20, 50, 100 kg ha −1 yr ) in boreal forest, we studied to explored potential role temporal precipitation variation plant stoichiometric mediating this. We found positive but changed nonlinearly time. Annual was positively related under high‐level addition; hence, hump‐shape pattern contributed nonlinear responses. After effects were accounted for, peaked seventh year then declined for all levels N. Later reductions could partly be attributed increased leaf N:phosphorus (P) ratio time, especially at higher rates. also an increase soil acid phosphatase, labile occluded P fraction, decreased resorption efficiency with increasing rates during late stage experiment, suggesting demand. Collectively, our results imply that nutrient stoichiometry cumulative input may limit stimulation while appears unlikely modulate atmospheric deposition.

Язык: Английский

Процитировано

0