2025-04-17 中国科学院(CAS)
<関連情報>
- https://english.cas.cn/newsroom/research_news/life/202504/t20250418_1041511.shtml
- https://www.sciencedirect.com/science/article/abs/pii/S0341816225003066?via%3Dihub
- https://link.springer.com/article/10.1007/s11104-025-07391-w
長期的な生態系の発展において、溶存有機物に対する気候と土壌形成の制御は異なる Climate and pedogenesis exert divergent controls on dissolved organic matter during long-term ecosystem development
Zhijian Mou, Yaoyao Hao, Xiaolin Chen, Tao Wang, Benjamin L. Turner, Ellen Kandeler, Hans Lambers, Zhanfeng Liu
CATENA Available online: 3 April 2025
DOI:https://doi.org/10.1016/j.catena.2025.109004
Graphical abstract
Highlights
- Fluorescence-PARAFAC reveals varied effects of climate and pedogenesis on soil DOM.
- Cooler, wetter climates promote DOM humification and stability in coastal ecosystem.
- DOM roles in nutrient cycle and soil carbon storage vary across soil chronosequence.
- Protein-like substances promote DOM bioavailability in early ecosystem development.
- Humic-like DOM increase stability and predominate in nutrient-depleted older soils.
Abstract
Dissolved organic matter (DOM) plays a central role in terrestrial carbon and nutrient cycling, underpinning essential ecosystem functions. Despite its importance, the mechanisms affecting long-term DOM dynamics during ecosystem development remain elusive due to complex variation in pedogenesis-associated nutrient status and biological activities. Here, we investigated the concentrations, optical properties, and compositional attributes of soil DOM across two 2-million-year coastal dune chronosequences under contrasting climatic conditions in southwestern Australia. Using fluorescence excitation-emission matrix spectroscopy coupled with parallel factor analysis, we elucidated distinct effects of climate and pedogenesis on DOM properties. Cooler and wetter climates were associated with greater DOM humification and accumulation. During the progressive phase of ecosystem development, both chronosequences exhibited greater topsoil DOM concentrations and proportions within soil organic matter (SOM), accompanied by a greater abundance of microbial-derived protein-like substances, which enhance DOM availability to microbes. Conversely, the retrogressive phase was characterized by lower DOM concentrations and proportions within SOM, alongside a transition to plant-derived humic substances and greater humification, suggesting increased DOM stability in old soils. Our findings highlight the dual role of DOM in providing bioavailable nutrients during the progressive phase and promoting soil carbon and nutrient accumulation during the retrogressive phase. These insights contribute to our understanding of the changing role of DOM during long-term ecosystem development and future climatic conditions.
パラドックスの解明:200万年前の砂丘年代系列における菌根バイオマスの減少に伴うグロマリン蓄積の増加 Unraveling the paradox: Increased glomalin accumulation amid declining mycorrhizal biomass across a two-million-year dune chronosequence
Zhijian Mou,Yaoyao Hao,Hans Lambers,Benjamin L. Turner,Ellen Kandeler & Zhanfeng Liu
Plant and Soil Published26 March 2025
DOIhttps://doi.org/10.1007/s11104-025-07391-w
Abstract
Background and aims
Arbuscular mycorrhizal fungi (AMF) are integral to the global carbon and nutrient cycles, primarily through the production of glomalin-related soil protein (GRSP), which contributes significantly to soil organic carbon (SOC) accumulation and ecosystem stability. However, the distribution pattern and environmental controls of GRSP during long-term ecosystem development are poorly understood.
Methods
Here, we investigated the dynamics of GRSP and its contribution to SOC accumulation along a 2-million-year chronosequence at Jurien Bay, south-western Australia, a biodiversity hotspot with severe phosphorus (P) deficiency.
Results
Our results revealed a progressive decline in AMF biomass with increasing soil age along the chronosequence, driven by P depletion and a reduction in the relative dominance of mycorrhizal plants (indicated by their relative canopy cover). Paradoxically, GRSP concentrations, especially easily-extractable GRSP (EE-GRSP), increased significantly along the chronosequence and peaked in the most weathered and severely P-impoverished soils. In addition, GRSP contributed up to 142 ± 15 mg SOC g⁻1, with increased production and stability facilitated by interactions with soil acidity, fine texture, nutrient stoichiometry, and mycorrhizal plant richness (the number of plant species that can form a symbiosis with AMF).
Conclusions
These results demonstrate that GRSP dynamics is primarily determined by AMF turnover, mycorrhizal plant species richness, and nutrient limitation, underscoring its critical role in SOC accumulation under nutrient-depleted conditions. This study advances our mechanistic understanding of AMF-mediated soil processes, with implications for sustainable land management and climate change mitigation in nutrient-limited yet biodiverse ecosystems.
