Terrestrial ecosystems contain significant carbon storage, vital to the global carbon cycle and climate change. Alterations in human production activities and environmental factors affect the stability of carbon storage in soil. Carbon sequestration in plant phytoliths offers a sustainable method for long-term carbon stabilization. Carbon occluded in phytoliths (PhytOC) is a kind of carbon that can be stable and not decomposed for a long time, so it is crucial to conduct more in-depth research on it. We undertook a meta-analysis on PhytOC across global terrestrial ecosystems, analyzing 60 articles, encapsulating 534 observations. We observed notable differences in phytolith and PhytOC contents across various ecosystems. Bamboo forest ecosystems exhibited the highest vegetation phytolith and PhytOC content, while soil phytolith content was most prominent in bamboo forests and PhytOC content in croplands. Human activities, such as grassland grazing, had a lesser impact on soil PhytOC transport than actions like cutting and tillage in croplands and forests. Our study separated bamboo ecosystems, analyzing their PhytOC content and revealing an underestimation of their carbon sink capacity. Notwithstanding our findings, phytoliths’ intricate environmental interactions warrant further exploration, crucial for refining ecosystem management and accurately estimating PhytOC stocks. This deepened understanding lays the foundation for studying phytoliths and the carbon sink dynamics.
{"title":"The phytolith carbon sequestration in terrestrial ecosystems: the underestimated potential of bamboo forest","authors":"Xuekun Cheng, Huiru Lv, Shuhan Liu, Chong Li, Pingheng Li, Yufeng Zhou, Yongjun Shi, Guomo Zhou","doi":"10.1186/s13717-023-00476-3","DOIUrl":"https://doi.org/10.1186/s13717-023-00476-3","url":null,"abstract":"Terrestrial ecosystems contain significant carbon storage, vital to the global carbon cycle and climate change. Alterations in human production activities and environmental factors affect the stability of carbon storage in soil. Carbon sequestration in plant phytoliths offers a sustainable method for long-term carbon stabilization. Carbon occluded in phytoliths (PhytOC) is a kind of carbon that can be stable and not decomposed for a long time, so it is crucial to conduct more in-depth research on it. We undertook a meta-analysis on PhytOC across global terrestrial ecosystems, analyzing 60 articles, encapsulating 534 observations. We observed notable differences in phytolith and PhytOC contents across various ecosystems. Bamboo forest ecosystems exhibited the highest vegetation phytolith and PhytOC content, while soil phytolith content was most prominent in bamboo forests and PhytOC content in croplands. Human activities, such as grassland grazing, had a lesser impact on soil PhytOC transport than actions like cutting and tillage in croplands and forests. Our study separated bamboo ecosystems, analyzing their PhytOC content and revealing an underestimation of their carbon sink capacity. Notwithstanding our findings, phytoliths’ intricate environmental interactions warrant further exploration, crucial for refining ecosystem management and accurately estimating PhytOC stocks. This deepened understanding lays the foundation for studying phytoliths and the carbon sink dynamics.","PeriodicalId":11419,"journal":{"name":"Ecological Processes","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138818632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Clarifying the enrichment and response processes of triclosan (TCS) in hydrophytes is crucial for assessing the ecological risk of TCS in aquatic environments. This study delves into the chronic toxic effects of TCS in floating plant Eichhornia crassipes (Mart.) Solms and submerged plant Hydrilla verticillata (L. f.) Royle exposed to TCS sediments through hydroponic experiments. The absorption abilities of hydrophytes to TCS were species-dependent. The concentration of TCS in the roots of E. crassipes was significantly higher than that in its leaves, while the absorption capacities of the leaves of H. verticillata to TCS were stronger than that in its roots. Furthermore, the physiological indexes, including chlorophyll concentration, soluble protein concentration, and antioxidant enzyme activities, showed a significant decrease with the exposure concentration and time of TCS. Although the chlorophyll and soluble protein concentrations and the antioxidant enzyme activities in the leaves were initially increased at a low concentration of TCS (at 7 days of exposure), they decreased significantly over time. Compared to the leaves, the physiological indexes of the roots were more sensitive to the ecotoxicological effects of TCS. The inhibition effects of TCS on H. verticillata were significantly higher than those on E. crassipes, which may be associated with the absorbing abilities of TCS and the growth characteristics of the plants. Pearson’s correlation analysis found a significant negative correlation between the TCS concentrations and the antioxidant enzyme activities in the plants. This study highlighted the differences in the uptake and enrichment process and toxic effects of TCS by different aquatic plants. Compared with E. crassipes, H. verticillata is more sensitive to TCS toxicity.
{"title":"Enrichment and toxic effects of triclosan on aquatic macrophytes Eichhornia crassipes and Hydrilla verticillata exposed to triclosan in sediments","authors":"Xiuxiu Yan, Fangyu Hu, Jing An, Yongchao Yin, Lingyan Zhang, Shuhe Wei","doi":"10.1186/s13717-023-00471-8","DOIUrl":"https://doi.org/10.1186/s13717-023-00471-8","url":null,"abstract":"Clarifying the enrichment and response processes of triclosan (TCS) in hydrophytes is crucial for assessing the ecological risk of TCS in aquatic environments. This study delves into the chronic toxic effects of TCS in floating plant Eichhornia crassipes (Mart.) Solms and submerged plant Hydrilla verticillata (L. f.) Royle exposed to TCS sediments through hydroponic experiments. The absorption abilities of hydrophytes to TCS were species-dependent. The concentration of TCS in the roots of E. crassipes was significantly higher than that in its leaves, while the absorption capacities of the leaves of H. verticillata to TCS were stronger than that in its roots. Furthermore, the physiological indexes, including chlorophyll concentration, soluble protein concentration, and antioxidant enzyme activities, showed a significant decrease with the exposure concentration and time of TCS. Although the chlorophyll and soluble protein concentrations and the antioxidant enzyme activities in the leaves were initially increased at a low concentration of TCS (at 7 days of exposure), they decreased significantly over time. Compared to the leaves, the physiological indexes of the roots were more sensitive to the ecotoxicological effects of TCS. The inhibition effects of TCS on H. verticillata were significantly higher than those on E. crassipes, which may be associated with the absorbing abilities of TCS and the growth characteristics of the plants. Pearson’s correlation analysis found a significant negative correlation between the TCS concentrations and the antioxidant enzyme activities in the plants. This study highlighted the differences in the uptake and enrichment process and toxic effects of TCS by different aquatic plants. Compared with E. crassipes, H. verticillata is more sensitive to TCS toxicity.","PeriodicalId":11419,"journal":{"name":"Ecological Processes","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138742017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-18DOI: 10.1186/s13717-023-00477-2
Jiangzhou Xia, Yang Chen, Wenping Yuan, Ying-Ping Wang
The allocation of photosynthate among the parts of plants (e.g., leaves, wood tissues and roots) strongly regulates their growth, and this conditions the terrestrial carbon cycle. Recent studies have shown that atmospheric CO2 and climate change dominate the changes in carbon allocation in plants, but the magnitude and mechanism of its effects remain unclear. The Community Atmosphere Biosphere Land Exchange (CABLE) model can accurately simulate the responses of carbon allocation to environmental changes. This study quantifies the contributions of four environmental factors—atmospheric CO2, temperature, precipitation, and radiation—on resource availability and carbon allocation from 1979 to 2014 by using the CABLE model. The results of the CABLE model showed that rising CO2 significantly reduced carbon allocation to the leaves of plants at a global scale, but the other three environmental factors exhibited contrasting effects that dominated the rise in carbon allocation to the leaves. The increased precipitation and CO2 significantly reduced the light availability and increased carbon allocation to the wooden parts of plants. By contrast, the rising temperature reduced the water availability, resulting in a decrease in carbon allocation to the wooden parts. All four environmental factors consistently exhibited negative effects on carbon allocation to the roots, with rising precipitation causing the largest reduction in carbon allocation to them. Moreover, except for CO2, the effects of the other three environmental factors were heterogeneous owing to their variable interactions in different regions. The CABLE model can accurately represent the mechanisms of response of resource availability and carbon allocation to environmental changes. Our study highlights the substantial environmental regulation of global carbon allocation. The responses of carbon allocation to global environmental changes need to be extensively studied through ecosystem models based on different hypotheses.
{"title":"The effects of multiple environmental factors on global carbon allocation","authors":"Jiangzhou Xia, Yang Chen, Wenping Yuan, Ying-Ping Wang","doi":"10.1186/s13717-023-00477-2","DOIUrl":"https://doi.org/10.1186/s13717-023-00477-2","url":null,"abstract":"The allocation of photosynthate among the parts of plants (e.g., leaves, wood tissues and roots) strongly regulates their growth, and this conditions the terrestrial carbon cycle. Recent studies have shown that atmospheric CO2 and climate change dominate the changes in carbon allocation in plants, but the magnitude and mechanism of its effects remain unclear. The Community Atmosphere Biosphere Land Exchange (CABLE) model can accurately simulate the responses of carbon allocation to environmental changes. This study quantifies the contributions of four environmental factors—atmospheric CO2, temperature, precipitation, and radiation—on resource availability and carbon allocation from 1979 to 2014 by using the CABLE model. The results of the CABLE model showed that rising CO2 significantly reduced carbon allocation to the leaves of plants at a global scale, but the other three environmental factors exhibited contrasting effects that dominated the rise in carbon allocation to the leaves. The increased precipitation and CO2 significantly reduced the light availability and increased carbon allocation to the wooden parts of plants. By contrast, the rising temperature reduced the water availability, resulting in a decrease in carbon allocation to the wooden parts. All four environmental factors consistently exhibited negative effects on carbon allocation to the roots, with rising precipitation causing the largest reduction in carbon allocation to them. Moreover, except for CO2, the effects of the other three environmental factors were heterogeneous owing to their variable interactions in different regions. The CABLE model can accurately represent the mechanisms of response of resource availability and carbon allocation to environmental changes. Our study highlights the substantial environmental regulation of global carbon allocation. The responses of carbon allocation to global environmental changes need to be extensively studied through ecosystem models based on different hypotheses.","PeriodicalId":11419,"journal":{"name":"Ecological Processes","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138715351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-12DOI: 10.1186/s13717-023-00473-6
Tingting Zhang, Nan Du, Zhi Geng, Sikai Wang, Yu Gao, Gang Yang, Xiaorong Huang, Tao Zhang, Ping Zhuang, Feng Zhao
The provision of habitat for fishery species in estuaries is highly valued and represents one of the most challenging ecosystem service values to quantify. However, quantifying this value is challenging due to complex relationships between habitat change, ecological processes, and environmental variations. This study aims to estimate estuarine habitat degradation and its impact on the reproduction process of the crab Eriocheir sinensis by characterizing the changes in breeding habitat and investigating relationships between the species and its habitat in the Yangtze River Estuary. A species distribution model recently developed was applied to estimate the extent and quality of breeding habitat changes from 2014–2021. The intrinsic (physiological) and external (structural) reproductive attributes of the breeding process were measured to assess the effects of habitat change. The relationships among habitat change, reproductive attributes and environmental factors were analyzed to understand the underlying driving forces of habitat degradation for breeding process by multivariate statistical analysis. About 34.24% of essential habitat was lost, mainly in highly suitable areas due to reclamation and waterway construction. Habitat degradation significantly affects female distribution and their reproductive processes, particularly gonad development during the pre-reproductive period and fecundity during the reproductive period, without altering population structure. These results indicated that the main ecological function served by the highly suitable breeding ground was the provision for development of gonad and improvement of fecundity. Increases of salinity and turbidity, caused by hydrodynamic changes from large-scale waterway construction, were identified as the environmental determinants contributing to cumulative habitat degradation. These influences ultimately led to a decrease in the fecundity of E. sinensis. Our research sheds light on the quantification of habitat degradation in the Yangtze River Estuary and its implications for the reproduction process of E. sinensis, which can serve as a foundation for assessing and quantifying the ecosystem service values provided by these breeding grounds. This information is valuable for policymakers and resource managers in making informed decisions regarding habitat conservation and the sustainable utilization of fishery resources.
{"title":"Estimation of estuarine habitat degradation and its influence on the reproduction process of the crab Eriocheir sinensis in the Yangtze River Estuary","authors":"Tingting Zhang, Nan Du, Zhi Geng, Sikai Wang, Yu Gao, Gang Yang, Xiaorong Huang, Tao Zhang, Ping Zhuang, Feng Zhao","doi":"10.1186/s13717-023-00473-6","DOIUrl":"https://doi.org/10.1186/s13717-023-00473-6","url":null,"abstract":"The provision of habitat for fishery species in estuaries is highly valued and represents one of the most challenging ecosystem service values to quantify. However, quantifying this value is challenging due to complex relationships between habitat change, ecological processes, and environmental variations. This study aims to estimate estuarine habitat degradation and its impact on the reproduction process of the crab Eriocheir sinensis by characterizing the changes in breeding habitat and investigating relationships between the species and its habitat in the Yangtze River Estuary. A species distribution model recently developed was applied to estimate the extent and quality of breeding habitat changes from 2014–2021. The intrinsic (physiological) and external (structural) reproductive attributes of the breeding process were measured to assess the effects of habitat change. The relationships among habitat change, reproductive attributes and environmental factors were analyzed to understand the underlying driving forces of habitat degradation for breeding process by multivariate statistical analysis. About 34.24% of essential habitat was lost, mainly in highly suitable areas due to reclamation and waterway construction. Habitat degradation significantly affects female distribution and their reproductive processes, particularly gonad development during the pre-reproductive period and fecundity during the reproductive period, without altering population structure. These results indicated that the main ecological function served by the highly suitable breeding ground was the provision for development of gonad and improvement of fecundity. Increases of salinity and turbidity, caused by hydrodynamic changes from large-scale waterway construction, were identified as the environmental determinants contributing to cumulative habitat degradation. These influences ultimately led to a decrease in the fecundity of E. sinensis. Our research sheds light on the quantification of habitat degradation in the Yangtze River Estuary and its implications for the reproduction process of E. sinensis, which can serve as a foundation for assessing and quantifying the ecosystem service values provided by these breeding grounds. This information is valuable for policymakers and resource managers in making informed decisions regarding habitat conservation and the sustainable utilization of fishery resources.","PeriodicalId":11419,"journal":{"name":"Ecological Processes","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138574792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-06DOI: 10.1186/s13717-023-00472-7
Daigard R. Ortega Rodriguez, Raúl Sánchez-Salguero, Andrea Hevia, Renata C. Bovi, Marciel J. Ferreira, James H. Speer, Fidel A. Roig, Mario Tomazello-Filho
The increase in the frequency and intensity of droughts is pointed out as one of the main factors altering biogeochemical cycles in the Amazon basin. An eco-nutritional approach using X-ray fluorescence micro-analysis (µXRF) is proposed to verify the long- and short-term effects of droughts on the growth and xylem nutrient concentrations of Cedrela fissilis Vell. Fourteen radii were selected from a tree-ring width chronology and X-rayed by Itrax Multiscanner. Profiles of ring width, wood density, and concentrations of aluminum (Al), phosphorus (P), sulfur (S), calcium (Ca), potassium (K), manganese (Mn), iron (Fe) and strontium (Sr) together with Al/Ca, Ca/Mn, K/Ca, Sr/Ca and Mn/S ratios were constructed and correlated with precipitation, temperature, the difference between precipitation and potential evapotranspiration (P-PET) and standardized precipitation–evapotranspiration index (SPEI). During dry years, C. fissilis showed narrower, less dense rings, lower Al, P, S and Ca, and higher K and Fe concentrations (the opposite was found in wet years). Ring width decreased (together with Al, P, S, K, Ca, Mn, Fe, Sr, Al/Ca, K/Ca and Sr/Ca) and wood density increased (together with Ca/Mn and Mn/S), which was associated with an increase in evapotranspiration and temperature over time, mainly since 1990. Cedrela fissilis showed a tendency to increase its capacity for resistance, and a recovery and resilience in growth over time associated with responses in Al, Ca, P and S. However, it showed a risk in the capacity for recovery of the pre-drought density values, associated with unsatisfactory responses in Al, Ca, K, Fe and P. This study is the first attempt to analyze tree-ring nutritional evidences of C. fissilis trees to climate sensitivity and resilience to drought, based on long-term data from seasonal moist tropical forests of the Amazon. Our data suggested that C. fissilis is undergoing alterations in the concentration, use and redistribution of nutrients associated with increasing wood density and decreasing growth over time, due to the increase of drought frequency in the southern Amazon.
{"title":"Does climate change alter the nutrient trends of Cedrela fissilis Vell. trees in the southern Brazilian Amazon?","authors":"Daigard R. Ortega Rodriguez, Raúl Sánchez-Salguero, Andrea Hevia, Renata C. Bovi, Marciel J. Ferreira, James H. Speer, Fidel A. Roig, Mario Tomazello-Filho","doi":"10.1186/s13717-023-00472-7","DOIUrl":"https://doi.org/10.1186/s13717-023-00472-7","url":null,"abstract":"The increase in the frequency and intensity of droughts is pointed out as one of the main factors altering biogeochemical cycles in the Amazon basin. An eco-nutritional approach using X-ray fluorescence micro-analysis (µXRF) is proposed to verify the long- and short-term effects of droughts on the growth and xylem nutrient concentrations of Cedrela fissilis Vell. Fourteen radii were selected from a tree-ring width chronology and X-rayed by Itrax Multiscanner. Profiles of ring width, wood density, and concentrations of aluminum (Al), phosphorus (P), sulfur (S), calcium (Ca), potassium (K), manganese (Mn), iron (Fe) and strontium (Sr) together with Al/Ca, Ca/Mn, K/Ca, Sr/Ca and Mn/S ratios were constructed and correlated with precipitation, temperature, the difference between precipitation and potential evapotranspiration (P-PET) and standardized precipitation–evapotranspiration index (SPEI). During dry years, C. fissilis showed narrower, less dense rings, lower Al, P, S and Ca, and higher K and Fe concentrations (the opposite was found in wet years). Ring width decreased (together with Al, P, S, K, Ca, Mn, Fe, Sr, Al/Ca, K/Ca and Sr/Ca) and wood density increased (together with Ca/Mn and Mn/S), which was associated with an increase in evapotranspiration and temperature over time, mainly since 1990. Cedrela fissilis showed a tendency to increase its capacity for resistance, and a recovery and resilience in growth over time associated with responses in Al, Ca, P and S. However, it showed a risk in the capacity for recovery of the pre-drought density values, associated with unsatisfactory responses in Al, Ca, K, Fe and P. This study is the first attempt to analyze tree-ring nutritional evidences of C. fissilis trees to climate sensitivity and resilience to drought, based on long-term data from seasonal moist tropical forests of the Amazon. Our data suggested that C. fissilis is undergoing alterations in the concentration, use and redistribution of nutrients associated with increasing wood density and decreasing growth over time, due to the increase of drought frequency in the southern Amazon.","PeriodicalId":11419,"journal":{"name":"Ecological Processes","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138538119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.1186/s13717-023-00466-5
Wangchen Sonam, Yongqin Liu, Liangdong Guo
Microbial communities in different plant compartments are relatively independent entities. However, the influence of environmental factors on the microbial community in different compartments of periglacial plants remains unclear. In this study, we quantified the bacterial communities in the rhizosphere soil, as well as root and leaf endosphere compartments of a periglacial plant, Potentilla fruticosa var. albicans, using high-throughput DNA sequencing. Moreover, we evaluated the impacts of habitat types (glacier terminus zone, moraine ridge, and alpine meadow) on the bacterial community in different plant compartments of Potentilla fruticosa var. albicans. Our results showed that habitat type had a significant effect on the alpha diversity (Chao1 richness) of endophytic bacteria, but not on the rhizospheric bacteria. The community composition of rhizospheric and endophytic bacteria was significantly different across the three habitats, and habitat type had a greater effect on the endophytic bacteria than on rhizospheric bacteria. The contribution of rhizosphere soil to the root and leaf endophytes decreased with the transformation of habitats from glacier terminus zone to alpine meadow. In contrast, host selection pressure sequentially increased from the glacier terminus zone to the moraine ridge to the alpine meadow. Furthermore, we found that the bacterial co-occurrence network in the alpine meadow was more modular but had lower complexity and connectedness than that in the glacier terminus zone. The bacterial community was governed primarily by stochastic processes regardless of habitat type. This study reveals that the diversity and composition of endophytic bacteria associated with Potentilla fruticosa var. albicans are more affected by habitat types than that of rhizospheric bacteria. Our study also demonstrates that the assembly patterns and co-occurrence patterns of bacterial communities associated with Potentilla fruticosa var. albicans vary by habitat type. These results advance the current understanding of community assembly and ecological interactions of microbial communities associated with periglacial plants.
不同植物室的微生物群落是相对独立的实体。然而,环境因子对冰缘植物不同区室微生物群落的影响尚不清楚。在这项研究中,我们使用高通量DNA测序技术定量了冰缘植物白白Potentilla fruticosa var. albicans根际土壤中的细菌群落,以及根和叶的内圈区室。此外,我们还评估了不同生境类型(冰川终端区、冰碛垄和高寒草甸)对白白蕨不同植物室细菌群落的影响。结果表明,生境类型对内生细菌的α多样性(Chao1丰富度)有显著影响,但对根际细菌没有显著影响。不同生境根际细菌和内生细菌的群落组成差异显著,生境类型对根际细菌的影响大于对根际细菌的影响。根际土壤对根和叶内生菌的贡献随着生境由冰川终端区向高寒草甸的转变而减小。从冰川终端区到冰碛垄再到高寒草甸,寄主选择压力依次增大。与冰川终端区相比,高寒草甸的细菌共生网络更模块化,但复杂性和连通性较低。与生境类型无关,细菌群落主要受随机过程控制。本研究表明,与白白翻陵草相关的内生细菌多样性和组成受生境类型的影响大于根际细菌的影响。我们的研究还表明,与白僵菌相关的细菌群落的聚集模式和共生模式因生境类型而异。这些结果促进了目前对冰缘植物微生物群落组成和生态相互作用的认识。
{"title":"Endophytic bacteria in the periglacial plant Potentilla fruticosa var. albicans are influenced by habitat type","authors":"Wangchen Sonam, Yongqin Liu, Liangdong Guo","doi":"10.1186/s13717-023-00466-5","DOIUrl":"https://doi.org/10.1186/s13717-023-00466-5","url":null,"abstract":"Microbial communities in different plant compartments are relatively independent entities. However, the influence of environmental factors on the microbial community in different compartments of periglacial plants remains unclear. In this study, we quantified the bacterial communities in the rhizosphere soil, as well as root and leaf endosphere compartments of a periglacial plant, Potentilla fruticosa var. albicans, using high-throughput DNA sequencing. Moreover, we evaluated the impacts of habitat types (glacier terminus zone, moraine ridge, and alpine meadow) on the bacterial community in different plant compartments of Potentilla fruticosa var. albicans. Our results showed that habitat type had a significant effect on the alpha diversity (Chao1 richness) of endophytic bacteria, but not on the rhizospheric bacteria. The community composition of rhizospheric and endophytic bacteria was significantly different across the three habitats, and habitat type had a greater effect on the endophytic bacteria than on rhizospheric bacteria. The contribution of rhizosphere soil to the root and leaf endophytes decreased with the transformation of habitats from glacier terminus zone to alpine meadow. In contrast, host selection pressure sequentially increased from the glacier terminus zone to the moraine ridge to the alpine meadow. Furthermore, we found that the bacterial co-occurrence network in the alpine meadow was more modular but had lower complexity and connectedness than that in the glacier terminus zone. The bacterial community was governed primarily by stochastic processes regardless of habitat type. This study reveals that the diversity and composition of endophytic bacteria associated with Potentilla fruticosa var. albicans are more affected by habitat types than that of rhizospheric bacteria. Our study also demonstrates that the assembly patterns and co-occurrence patterns of bacterial communities associated with Potentilla fruticosa var. albicans vary by habitat type. These results advance the current understanding of community assembly and ecological interactions of microbial communities associated with periglacial plants.","PeriodicalId":11419,"journal":{"name":"Ecological Processes","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138538099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-30DOI: 10.1186/s13717-023-00470-9
Xinyu Wei, Fuzhong Wu, Koenraad Van Meerbeek, Ellen Desie, Xiangyin Ni, Kai Yue, Petr Heděnec, Jing Yang, Nannan An
Changes in soil greenhouse gas (GHG) fluxes caused by nitrogen (N) addition are considered as the key factors contributing to global climate change (global warming and altered precipitation regimes), which in turn alters the feedback between N addition and soil GHG fluxes. However, the effects of N addition on soil GHG emissions under climate change are highly variable and context-dependent, so that further syntheses are required. Here, a meta-analysis of the interactive effects of N addition and climate change (warming and altered precipitation) on the fluxes of three main soil GHGs [carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O)] was conducted by synthesizing 2103 observations retrieved from 57 peer-reviewed articles on multiple terrestrial ecosystems globally. The interactive effects of N addition and climate change on GHG fluxes were generally additive. The combination of N addition and warming or altered precipitation increased N2O emissions significantly while it had minimal effects on CO2 emissions and CH4 uptake, and the effects on CH4 emissions could not be evaluated. Moreover, the magnitude of the combined effects did not differ significantly from the effects of N addition alone. Apparently, the combined effects on CO2 and CH4 varied among ecosystem types due to differences in soil moisture, which was in contrast to the soil N2O emission responses. The soil GHG flux responses to combined N addition and climate change also varied among different climatic conditions and experimental methods. Overall, our findings indicate that the effects of N addition and climate change on soil GHG fluxes were relatively independent, i.e. combined effects of N addition and climate change were equal to or not significantly different from the sum of their respective individual effects. The effects of N addition on soil GHG fluxes influence the feedbacks between climate change and soil GHG fluxes.
{"title":"Warming and altered precipitation rarely alter N addition effects on soil greenhouse gas fluxes: a meta-analysis","authors":"Xinyu Wei, Fuzhong Wu, Koenraad Van Meerbeek, Ellen Desie, Xiangyin Ni, Kai Yue, Petr Heděnec, Jing Yang, Nannan An","doi":"10.1186/s13717-023-00470-9","DOIUrl":"https://doi.org/10.1186/s13717-023-00470-9","url":null,"abstract":"Changes in soil greenhouse gas (GHG) fluxes caused by nitrogen (N) addition are considered as the key factors contributing to global climate change (global warming and altered precipitation regimes), which in turn alters the feedback between N addition and soil GHG fluxes. However, the effects of N addition on soil GHG emissions under climate change are highly variable and context-dependent, so that further syntheses are required. Here, a meta-analysis of the interactive effects of N addition and climate change (warming and altered precipitation) on the fluxes of three main soil GHGs [carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O)] was conducted by synthesizing 2103 observations retrieved from 57 peer-reviewed articles on multiple terrestrial ecosystems globally. The interactive effects of N addition and climate change on GHG fluxes were generally additive. The combination of N addition and warming or altered precipitation increased N2O emissions significantly while it had minimal effects on CO2 emissions and CH4 uptake, and the effects on CH4 emissions could not be evaluated. Moreover, the magnitude of the combined effects did not differ significantly from the effects of N addition alone. Apparently, the combined effects on CO2 and CH4 varied among ecosystem types due to differences in soil moisture, which was in contrast to the soil N2O emission responses. The soil GHG flux responses to combined N addition and climate change also varied among different climatic conditions and experimental methods. Overall, our findings indicate that the effects of N addition and climate change on soil GHG fluxes were relatively independent, i.e. combined effects of N addition and climate change were equal to or not significantly different from the sum of their respective individual effects. The effects of N addition on soil GHG fluxes influence the feedbacks between climate change and soil GHG fluxes.","PeriodicalId":11419,"journal":{"name":"Ecological Processes","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138538120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-28DOI: 10.1186/s13717-023-00467-4
Yan Li, Xi Qi, Jianpan Xin, Chu Zhao, Runan Tian
Eutrophication and acid rain are two threats that many water bodies must contend with. Eutrophication and climate change have accelerated widespread outbreaks of cyanobacterial blooms as both have become more severe. Pontederia cordata, a garden ornamental plant, can inhibit some algae growth and remove total nitrogen (TN) and total phosphorus (TP) from the water. In this study, we investigated how simulated acid rain and eutrophication co-pollution affected P. cordata's growth physiology and ability to inhibit algae growth. Under mild eutrophication (2 mg·L−1 TN, 0.4 mg·L−1 TP, and 15 mg·L−1 CODMn) or weak acid rain (pH = 5.0), P. cordata alleviated the degree of cell membrane lipid peroxidation by stabilizing superoxide dismutase (SOD) and catalase (CAT) activities in the leaves, allowing for normal plant growth. Under mild eutrophication and acid rain conditions, cultured P. cordata water samples maintained strong algae inhibition by reducing the Chl a content and SOD activity of Microcystis aeruginosa cells. Compound stress where acid rain was the primary inhibitory factor along with moderate or severe eutrophication inhibited P. cordata growth, which probably reduced the input of algae-inhibiting allelochemicals, thus reducing its ability to inhibit algae. In summary, P. cordata has application potential in mild eutrophic water and acid rain (pH ≥ 4). These findings provide guidance for further research on phytoremediation and algae control in scenarios of compound pollution.
{"title":"Physiological responses and algae inhibition of Pontederia cordata to simulated eutrophication and acid rain co-pollution","authors":"Yan Li, Xi Qi, Jianpan Xin, Chu Zhao, Runan Tian","doi":"10.1186/s13717-023-00467-4","DOIUrl":"https://doi.org/10.1186/s13717-023-00467-4","url":null,"abstract":"Eutrophication and acid rain are two threats that many water bodies must contend with. Eutrophication and climate change have accelerated widespread outbreaks of cyanobacterial blooms as both have become more severe. Pontederia cordata, a garden ornamental plant, can inhibit some algae growth and remove total nitrogen (TN) and total phosphorus (TP) from the water. In this study, we investigated how simulated acid rain and eutrophication co-pollution affected P. cordata's growth physiology and ability to inhibit algae growth. Under mild eutrophication (2 mg·L−1 TN, 0.4 mg·L−1 TP, and 15 mg·L−1 CODMn) or weak acid rain (pH = 5.0), P. cordata alleviated the degree of cell membrane lipid peroxidation by stabilizing superoxide dismutase (SOD) and catalase (CAT) activities in the leaves, allowing for normal plant growth. Under mild eutrophication and acid rain conditions, cultured P. cordata water samples maintained strong algae inhibition by reducing the Chl a content and SOD activity of Microcystis aeruginosa cells. Compound stress where acid rain was the primary inhibitory factor along with moderate or severe eutrophication inhibited P. cordata growth, which probably reduced the input of algae-inhibiting allelochemicals, thus reducing its ability to inhibit algae. In summary, P. cordata has application potential in mild eutrophic water and acid rain (pH ≥ 4). These findings provide guidance for further research on phytoremediation and algae control in scenarios of compound pollution.","PeriodicalId":11419,"journal":{"name":"Ecological Processes","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138538117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-17DOI: 10.1186/s13717-023-00468-3
Haftay Hailu Gebremedhn, Ousmane Ndiaye, Sylvanus Mensah, Cofélas Fassinou, Simon Taugourdeau, Torbern Tagesson, Paulo Salgado
The savannah ecosystems of Sahel have experienced continuous and heavy grazing of livestock for centuries but still, their vegetation response to grazing pressure remains poorly understood. In this study, we analysed the herbaceous plant dynamics, measured by species diversity, composition, cover, and biomass in response to grazing pressure in the savannah ecosystems of Sahel. In Senegal, we selected four savannah sites represented with high, moderate, light and no grazing intensity levels. Transect survey methods were used for sampling the vegetation data within each of the sites. Species richness and composition were analysed using species accumulation curve and multivariate analyses. Furthermore, we used General Linear Models and a piecewise Structural Equation Model (pSEM) to examine the relationships between grazing intensity, vegetation cover, diversity and biomass. The herbaceous species diversity and composition varied significantly among the different grazing intensity levels (p <0.001). The plant species composition shifted from the dominance of grass cover to the dominance of forb cover with increasing grazing pressure. Moreover, the attributes of species diversity, herbaceous biomass, and ground cover were higher on sites with low grazing than sites with high and moderate grazing intensity. Across all sites, species diversity was positively related to total biomass. The pSEM explained 37% of the variance in total biomass and revealed that grazing intensity negatively influenced total biomass both directly and indirectly through its negative influence on species diversity. Managing grazing intensity may lead to higher plant production and higher mixed forage establishment in the dryland savannah ecosystems. This information can be used to support land management strategies and promote sustainable grazing practices that balance the needs of livestock with the conservation of ecosystem health and biodiversity.
几个世纪以来,萨赫勒草原生态系统经历了持续和大量的牲畜放牧,但其植被对放牧压力的反应仍然知之甚少。在本研究中,我们分析了萨赫勒草原生态系统中草本植物对放牧压力的响应,包括物种多样性、组成、覆盖和生物量。在塞内加尔,我们选择了四个草原遗址,分别代表高、中等、轻度和无放牧强度水平。采用样带调查方法对每个站点内的植被数据进行采样。利用物种积累曲线和多变量分析对物种丰富度和组成进行了分析。利用一般线性模型(General Linear Models)和分段结构方程模型(piecwise Structural Equation Model, pSEM)分析了放牧强度、植被覆盖度、多样性和生物量之间的关系。不同放牧强度下草本物种多样性和组成差异显著(p <0.001)。随着放牧压力的增加,植物种类组成由草被为主向草被为主转变。低放牧区的物种多样性、草本生物量和地被盖度均高于高放牧区和中等放牧区。所有样地的物种多样性均与总生物量呈正相关。该模型解释了总生物量变化的37%,揭示了放牧强度通过对物种多样性的负向影响直接和间接地对总生物量产生负向影响。管理放牧强度可以提高旱地草原生态系统的植物产量和混合饲料的建立。这些信息可用于支持土地管理战略和促进可持续放牧做法,以平衡牲畜的需求与保护生态系统健康和生物多样性。
{"title":"Grazing effects on vegetation dynamics in the savannah ecosystems of the Sahel","authors":"Haftay Hailu Gebremedhn, Ousmane Ndiaye, Sylvanus Mensah, Cofélas Fassinou, Simon Taugourdeau, Torbern Tagesson, Paulo Salgado","doi":"10.1186/s13717-023-00468-3","DOIUrl":"https://doi.org/10.1186/s13717-023-00468-3","url":null,"abstract":"The savannah ecosystems of Sahel have experienced continuous and heavy grazing of livestock for centuries but still, their vegetation response to grazing pressure remains poorly understood. In this study, we analysed the herbaceous plant dynamics, measured by species diversity, composition, cover, and biomass in response to grazing pressure in the savannah ecosystems of Sahel. In Senegal, we selected four savannah sites represented with high, moderate, light and no grazing intensity levels. Transect survey methods were used for sampling the vegetation data within each of the sites. Species richness and composition were analysed using species accumulation curve and multivariate analyses. Furthermore, we used General Linear Models and a piecewise Structural Equation Model (pSEM) to examine the relationships between grazing intensity, vegetation cover, diversity and biomass. The herbaceous species diversity and composition varied significantly among the different grazing intensity levels (p <0.001). The plant species composition shifted from the dominance of grass cover to the dominance of forb cover with increasing grazing pressure. Moreover, the attributes of species diversity, herbaceous biomass, and ground cover were higher on sites with low grazing than sites with high and moderate grazing intensity. Across all sites, species diversity was positively related to total biomass. The pSEM explained 37% of the variance in total biomass and revealed that grazing intensity negatively influenced total biomass both directly and indirectly through its negative influence on species diversity. Managing grazing intensity may lead to higher plant production and higher mixed forage establishment in the dryland savannah ecosystems. This information can be used to support land management strategies and promote sustainable grazing practices that balance the needs of livestock with the conservation of ecosystem health and biodiversity.","PeriodicalId":11419,"journal":{"name":"Ecological Processes","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138538106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Background In the Indo-Gangetic Plain, rice–wheat is the most extensively practiced crop rotation. The escalating issue of crop residue burning, particularly rice straw, and the necessity to lower the exorbitant expenses associated with fertilizer inputs stand out as significant challenges for farmers in the region. A well-suited integrated nutrient management (INM) strategy that focuses on recycling crop residues can serve as a solution to address these issues. Such a strategy not only mitigates air pollution resulting from residue burning but also helps combat water pollution due to nitrate losses from agroecosystems. Field experiments were used to evaluate the suitability of eight INM-modules that included various combinations of inorganic fertilizer rates (50%, 100%, 150% of recommended dose), crop residues (wheat and rice stubble retention at 30 cm standing stubble equivalent to 1/3 the straw yield), rice straw compost (RSC), farmyard manure (FYM), and green manuring (GM), compared to 100% recommended dose of fertilizers (F) and no fertilizer application. Results There was a considerable improvement in nitrogen mineralization, grain yields, and nitrogen use efficiency under GM + RSC-F50 and GM + FYM-F50. These INM modules would permit a 50% reduction in the use of chemical fertilizers. There was a little yield penalty with in situ rice residue incorporation at 100% F; however, this could be overcome with 150% F fertilizer application. In situ retention of wheat straw with a full application of fertilizer resulted in steadily rising crop yields over time. Changes in the redox potential, soil pH, and soil organic carbon best accounted for the observed trajectories in nitrogen use efficiency. Conclusion The most promising INM modules for adoption by farmers in the Indo-Gangetic Plain to judiciously use crop residues and curtail chemical fertilizer inputs are green manuring with Sesbania aculeata + rice straw compost at 5 t ha −1 + only 50% of recommended dose of fertilizers (GM + RSC-F50), and green manuring with Sesbania aculeata + farmyard manure at 5 t ha −1 + only 50% of recommended dose of fertilizers (GM + FYM-F50). Sole incorporation of crop residues without nitrogen augmentation from other sources might not help curtail chemical fertilizer use. Composting rice straw, which otherwise is widely burnt, proved a useful nitrogen source and a vital component of INM. Waste rice straw composting at the community scale and its application as a nutrient source can help achieve sustainable nitrogen management in the agroecosystems of Indo-Gangetic Plain.
背景在印度恒河平原,水稻-小麦是最广泛实行的作物轮作。农作物秸秆焚烧问题日益严重,尤其是秸秆焚烧问题,以及降低化肥投入相关费用的必要性,都是该地区农民面临的重大挑战。一个非常适合的综合营养管理(INM)战略,侧重于作物残留物的循环利用,可以作为解决这些问题的解决方案。这一战略不仅减轻了燃烧残渣造成的空气污染,而且还有助于防治农业生态系统中硝酸盐损失造成的水污染。通过田间试验,对8个inm模块的适宜性进行了评价,这些模块包括不同组合的无机肥料用量(推荐用量的50%、100%和150%)、作物残茬(小麦和水稻留茬30 cm相当于秸秆产量的1/3)、秸秆堆肥(RSC)、农家粪肥(FYM)和绿色施肥(GM),与100%推荐用量的肥料(F)和不施肥相比。结果GM + RSC-F50和GM + fys - f50处理在氮素矿化、产量和氮素利用效率方面均有显著提高。这些INM模块将使化学肥料的使用减少50%。在100% F条件下,稻渣就地掺入对产量影响不大;然而,这可以通过150%的F肥施用来克服。随着时间的推移,小麦秸秆的原位保留和充分施用化肥导致作物产量稳步上升。氧化还原电位、土壤pH和土壤有机碳的变化最能解释氮利用效率的变化轨迹。结论印度河-恒河平原农民为合理利用作物秸秆和减少化肥投入而采用的最有希望的INM模式是田菁+水稻秸秆堆肥5 t / h - 1 +仅为化肥推荐用量的50% (GM + RSC-F50)和田菁+农家肥5 t / h - 1 +仅为化肥推荐用量的50% (GM + fsm - f50)的绿色施肥。在没有从其他来源补充氮肥的情况下,单独掺入作物秸秆可能无助于减少化肥的使用。秸秆堆肥被证明是一种有用的氮源,也是INM的重要组成部分。群落尺度的废稻草堆肥及其作为营养源的应用有助于印度恒河平原农业生态系统实现可持续的氮素管理。
{"title":"Residue recycling options and their implications for sustainable nitrogen management in rice–wheat agroecosystems","authors":"Ajay Kumar Bhardwaj, Kapil Malik, Manu Rani, Uttam Kumar Mandal, Nirmalendu Basak, Awtar Singh, Rajender Kumar Yadav, Suresh Kumar Chaudhari, Dinesh Kumar Sharma","doi":"10.1186/s13717-023-00464-7","DOIUrl":"https://doi.org/10.1186/s13717-023-00464-7","url":null,"abstract":"Abstract Background In the Indo-Gangetic Plain, rice–wheat is the most extensively practiced crop rotation. The escalating issue of crop residue burning, particularly rice straw, and the necessity to lower the exorbitant expenses associated with fertilizer inputs stand out as significant challenges for farmers in the region. A well-suited integrated nutrient management (INM) strategy that focuses on recycling crop residues can serve as a solution to address these issues. Such a strategy not only mitigates air pollution resulting from residue burning but also helps combat water pollution due to nitrate losses from agroecosystems. Field experiments were used to evaluate the suitability of eight INM-modules that included various combinations of inorganic fertilizer rates (50%, 100%, 150% of recommended dose), crop residues (wheat and rice stubble retention at 30 cm standing stubble equivalent to 1/3 the straw yield), rice straw compost (RSC), farmyard manure (FYM), and green manuring (GM), compared to 100% recommended dose of fertilizers (F) and no fertilizer application. Results There was a considerable improvement in nitrogen mineralization, grain yields, and nitrogen use efficiency under GM + RSC-F50 and GM + FYM-F50. These INM modules would permit a 50% reduction in the use of chemical fertilizers. There was a little yield penalty with in situ rice residue incorporation at 100% F; however, this could be overcome with 150% F fertilizer application. In situ retention of wheat straw with a full application of fertilizer resulted in steadily rising crop yields over time. Changes in the redox potential, soil pH, and soil organic carbon best accounted for the observed trajectories in nitrogen use efficiency. Conclusion The most promising INM modules for adoption by farmers in the Indo-Gangetic Plain to judiciously use crop residues and curtail chemical fertilizer inputs are green manuring with Sesbania aculeata + rice straw compost at 5 t ha −1 + only 50% of recommended dose of fertilizers (GM + RSC-F50), and green manuring with Sesbania aculeata + farmyard manure at 5 t ha −1 + only 50% of recommended dose of fertilizers (GM + FYM-F50). Sole incorporation of crop residues without nitrogen augmentation from other sources might not help curtail chemical fertilizer use. Composting rice straw, which otherwise is widely burnt, proved a useful nitrogen source and a vital component of INM. Waste rice straw composting at the community scale and its application as a nutrient source can help achieve sustainable nitrogen management in the agroecosystems of Indo-Gangetic Plain.","PeriodicalId":11419,"journal":{"name":"Ecological Processes","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135137685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}