Phosphorus(P),as a limiting nutrient,plays a crucial role in the mountainous ecosystem development.Its biogeochemical cycle in mountainous ecosystems determines the bioavailability and sustainable supply of P,and thus...Phosphorus(P),as a limiting nutrient,plays a crucial role in the mountainous ecosystem development.Its biogeochemical cycle in mountainous ecosystems determines the bioavailability and sustainable supply of P,and thus becomes a crucial process which needs to be fully understood and described for ecological and environmental conservation.However,most of research about P biogeochemical processes has been carried out in aquatic environment and agronomic field,but rare researches have been done in mountain ecosystem.In the present review,we summarize researches on P biogeochemical cycle concerning mountain ecosystem in recent decades,including rock weathering,the release,transformation and bioavailability of P,interactions between the P biological cycle and microbial and plant life,as well as the development of models.Based on the state of art,we propose the future work on this direction,including the integration of all these research,the development of a practical model to understand the P biogeochemical cycle and its bioavailability,and to provide a reference for ecological and environmental conservation of mountainous ecosystems and lowland aquatic systems.展开更多
New terrestrial habitats have emerged and a primary succession has developed in the retreat area(29°34'N, 102°00'E, 2951–2886 m) after the retreat of the Hailuogou glacier. To investigate soil micro...New terrestrial habitats have emerged and a primary succession has developed in the retreat area(29°34'N, 102°00'E, 2951–2886 m) after the retreat of the Hailuogou glacier. To investigate soil microbial changes along the primary successional chronosequence, mixed soil samples were collected at six sites at different ages(2 young sites, 2 mid-aged sites, and 2 old sites). The RNA was extracted and amplified. Bacterial 16 S r RNA and fungal 18 S r RNA were analyzed using high-throughput 454 pyrosequencing analysis. Overall, pyrosequencing showed that Proteobacteria, Acidobacteria, Bacteroidetes and Actinobacteria were the main bacterial phyla, and the fungal communities were strongly dominated by the phyla Ascomycota and Basidiomycota in the retreat area. The Shannon diversity index(Hshannon) of bacteria was 6.5 – 7.9, and that of fungi was 2.2 – 4.1 in these sites. For the bacterial communities, diversity and evenness values were highest on the mid-age sites and wererelatively low on the young and old sites. A similar trend was observed for the fungal communities. In contrast, soil properties showed significant linear distributional trends(increase or decrease) with the age of the site. Combining the linear change patterns of soil properties, the highest values of bacterial and fungal evenness and diversity in the mid-aged sites indicated that there was less environmental stress and more niches for microbial communities in the middle successional stage compare with other stages. In addition, our analysis showed that microbial communities were the main drivers that build a soil organic matter pool to expedite pedogenesis for ecosystem succession. This primary succession in the Hailuogou glacier retreat area is developing rapidly compared with that in other glacier retreats.展开更多
The distribution of trace metals in remote alpine region is an effective way to understand the impacts of regional human activity and vegetation on the alpine ecosystem. In this study, the concentrations of cadmium(Cd...The distribution of trace metals in remote alpine region is an effective way to understand the impacts of regional human activity and vegetation on the alpine ecosystem. In this study, the concentrations of cadmium(Cd), copper(Cu), lead(Pb), and zinc(Zn) in the soils of Gongga Mountain, Eastern Tibetan Plateau, were investigated to reveal their seasonal and spatial distribution and enrichment state, and to decipher the effects of atmospheric deposition and vegetation on their distributions among five vegetation zones. The results showed that the concentrations of Cd, Pb, and Zn were higher in the O horizon than in other horizons despite the seasonal changes, whereas Cu was enriched in the C horizon. The enrichment states of the metals studied in the soils decreased in the order of Cd > Pb > Zn > Cu. Cd and Pb were mainly sourced from atmospheric deposition; Zn was from both atmospheric deposition and parent materials, whereas Cu was mainly from parent materials.Seasonally, the trace metals were generally higher in May and December but lower in September, implying the impact of vegetation on the distribution of trace metals under the plant uptake and the litter decomposition. Spatially, the higher enrichment of Cu, Pb, and Zn in the soils existed in the mixed broadleafconiferous forests and coniferous forests(approximately 3000 m above sea level). The results suggested that atmospheric deposition and biological processes are main factors controlling the seasonal and spatial distribution of trace metals in the soils of the remote alpine ecosystem.展开更多
Water level is an important index for studying hydrologic processes. Water level rise processes were studied in three catchments(catchment I, II, III in Chen Jiagou watershed in the Three Gorge Reservoir Area) with di...Water level is an important index for studying hydrologic processes. Water level rise processes were studied in three catchments(catchment I, II, III in Chen Jiagou watershed in the Three Gorge Reservoir Area) with different areas to provide useful information to inform data extension from a gauged-catchment to an ungauged catchment. The results showed that there are seasonal changes in the dominant driving mode of the rise of the water level. The rise of the water level in March is likely mainly driven by the mode of stored-full runoff, and in September or October, it is mainly driven by Horton-flow. The correlation coefficients of all indexes were significant among the three catchments, suggesting that these catchments have similarities and that water level data extension is likely to be completed successfully between the large catchment(III-Catchment) and the small catchment(ICatchment). It was confirmed that there is good similarity between the 0.6 km^2 and 6 km^2 catchments, and the data correlation is good between the catchments with the area differences in the Three Gorges Reservoir Area. In addition, the rise processes of the water level in the catchments were not only different under the same rain conditions, but this difference could also change with the rain condition.展开更多
基金funded by Chinese Academy of Sciences (Grant Nos. KZCX2-YW-BR-21 and KZZD-EW-TZ-06)Natural Science Foundation of China (Grant No. 41272200)
文摘Phosphorus(P),as a limiting nutrient,plays a crucial role in the mountainous ecosystem development.Its biogeochemical cycle in mountainous ecosystems determines the bioavailability and sustainable supply of P,and thus becomes a crucial process which needs to be fully understood and described for ecological and environmental conservation.However,most of research about P biogeochemical processes has been carried out in aquatic environment and agronomic field,but rare researches have been done in mountain ecosystem.In the present review,we summarize researches on P biogeochemical cycle concerning mountain ecosystem in recent decades,including rock weathering,the release,transformation and bioavailability of P,interactions between the P biological cycle and microbial and plant life,as well as the development of models.Based on the state of art,we propose the future work on this direction,including the integration of all these research,the development of a practical model to understand the P biogeochemical cycle and its bioavailability,and to provide a reference for ecological and environmental conservation of mountainous ecosystems and lowland aquatic systems.
基金funded by the National Natural Science Foundation of China(Grant Nos.41501281 and 41272200)the Chinese Academy of Sciences(CAS "Light of West China" Program)
文摘New terrestrial habitats have emerged and a primary succession has developed in the retreat area(29°34'N, 102°00'E, 2951–2886 m) after the retreat of the Hailuogou glacier. To investigate soil microbial changes along the primary successional chronosequence, mixed soil samples were collected at six sites at different ages(2 young sites, 2 mid-aged sites, and 2 old sites). The RNA was extracted and amplified. Bacterial 16 S r RNA and fungal 18 S r RNA were analyzed using high-throughput 454 pyrosequencing analysis. Overall, pyrosequencing showed that Proteobacteria, Acidobacteria, Bacteroidetes and Actinobacteria were the main bacterial phyla, and the fungal communities were strongly dominated by the phyla Ascomycota and Basidiomycota in the retreat area. The Shannon diversity index(Hshannon) of bacteria was 6.5 – 7.9, and that of fungi was 2.2 – 4.1 in these sites. For the bacterial communities, diversity and evenness values were highest on the mid-age sites and wererelatively low on the young and old sites. A similar trend was observed for the fungal communities. In contrast, soil properties showed significant linear distributional trends(increase or decrease) with the age of the site. Combining the linear change patterns of soil properties, the highest values of bacterial and fungal evenness and diversity in the mid-aged sites indicated that there was less environmental stress and more niches for microbial communities in the middle successional stage compare with other stages. In addition, our analysis showed that microbial communities were the main drivers that build a soil organic matter pool to expedite pedogenesis for ecosystem succession. This primary succession in the Hailuogou glacier retreat area is developing rapidly compared with that in other glacier retreats.
基金supported by National Natural Science Foundation of China (Grant No. 41402313, Grant No. 41272200)National Key Research and Development Program of China (2016YFC0502401)the Fundamental Research Funds of Institute of Karst Geology, Chinese Academy of Geological Sciences (No. 2017008)
文摘The distribution of trace metals in remote alpine region is an effective way to understand the impacts of regional human activity and vegetation on the alpine ecosystem. In this study, the concentrations of cadmium(Cd), copper(Cu), lead(Pb), and zinc(Zn) in the soils of Gongga Mountain, Eastern Tibetan Plateau, were investigated to reveal their seasonal and spatial distribution and enrichment state, and to decipher the effects of atmospheric deposition and vegetation on their distributions among five vegetation zones. The results showed that the concentrations of Cd, Pb, and Zn were higher in the O horizon than in other horizons despite the seasonal changes, whereas Cu was enriched in the C horizon. The enrichment states of the metals studied in the soils decreased in the order of Cd > Pb > Zn > Cu. Cd and Pb were mainly sourced from atmospheric deposition; Zn was from both atmospheric deposition and parent materials, whereas Cu was mainly from parent materials.Seasonally, the trace metals were generally higher in May and December but lower in September, implying the impact of vegetation on the distribution of trace metals under the plant uptake and the litter decomposition. Spatially, the higher enrichment of Cu, Pb, and Zn in the soils existed in the mixed broadleafconiferous forests and coniferous forests(approximately 3000 m above sea level). The results suggested that atmospheric deposition and biological processes are main factors controlling the seasonal and spatial distribution of trace metals in the soils of the remote alpine ecosystem.
基金funded by West Light Foundation of The Chinese Academy of Sciences,CASthe State Council Three Gorges Construction Committee Project of China
文摘Water level is an important index for studying hydrologic processes. Water level rise processes were studied in three catchments(catchment I, II, III in Chen Jiagou watershed in the Three Gorge Reservoir Area) with different areas to provide useful information to inform data extension from a gauged-catchment to an ungauged catchment. The results showed that there are seasonal changes in the dominant driving mode of the rise of the water level. The rise of the water level in March is likely mainly driven by the mode of stored-full runoff, and in September or October, it is mainly driven by Horton-flow. The correlation coefficients of all indexes were significant among the three catchments, suggesting that these catchments have similarities and that water level data extension is likely to be completed successfully between the large catchment(III-Catchment) and the small catchment(ICatchment). It was confirmed that there is good similarity between the 0.6 km^2 and 6 km^2 catchments, and the data correlation is good between the catchments with the area differences in the Three Gorges Reservoir Area. In addition, the rise processes of the water level in the catchments were not only different under the same rain conditions, but this difference could also change with the rain condition.