Brian Njoroge Mwangi, Yuelin Li, D. Otieno, Shi-zhong Liu, Shimin Wei, Ze Meng, Qianmei Zhang, De-qiang Zhang, Juxiu Liu, G. Chu, F. Haider, J. Tenhunen
The study aimed to show that droughts are increasing in frequency and intensity in the Dinghushan Biosphere Reserve and to illustrate the effects of seasonal droughts on carbon gain in a sub-tropical forest. This is in response to the threat posed by increased droughts due to global climate change. We used four drought indices to accurately determine periods of drought and periods of increased precipitation. Thereafter, the measured eddy flux and soil moisture content data collected from 2003 to 2014 were compared between the droughts and wet periods to determine drought impacts on the ecosystem carbon gain. Drought accounted for about 20% of the 12-year study period, with the highest drought events and severity occurring between 2012 and 2013. The average annual precipitation and air temperature during the study period were 1404.57 ±43.2 mm and 22.65 ±0.1 ℃, respectively, showing a decrease of 523 mm in precipitation and an increase of 2.55 ℃ in temperature, compared to the 30-year records (1990-2020). Contrary to most published data for most forest ecosystems globally, Dinghushan Biosphere Reserve recorded significant carbon gain during 60% of the drought period.
{"title":"Seasonal droughts drive up carbon gain in a sub-tropical forest","authors":"Brian Njoroge Mwangi, Yuelin Li, D. Otieno, Shi-zhong Liu, Shimin Wei, Ze Meng, Qianmei Zhang, De-qiang Zhang, Juxiu Liu, G. Chu, F. Haider, J. Tenhunen","doi":"10.1093/jpe/rtac088","DOIUrl":"https://doi.org/10.1093/jpe/rtac088","url":null,"abstract":"\u0000 The study aimed to show that droughts are increasing in frequency and intensity in the Dinghushan Biosphere Reserve and to illustrate the effects of seasonal droughts on carbon gain in a sub-tropical forest. This is in response to the threat posed by increased droughts due to global climate change. We used four drought indices to accurately determine periods of drought and periods of increased precipitation. Thereafter, the measured eddy flux and soil moisture content data collected from 2003 to 2014 were compared between the droughts and wet periods to determine drought impacts on the ecosystem carbon gain. Drought accounted for about 20% of the 12-year study period, with the highest drought events and severity occurring between 2012 and 2013. The average annual precipitation and air temperature during the study period were 1404.57 ±43.2 mm and 22.65 ±0.1 ℃, respectively, showing a decrease of 523 mm in precipitation and an increase of 2.55 ℃ in temperature, compared to the 30-year records (1990-2020). Contrary to most published data for most forest ecosystems globally, Dinghushan Biosphere Reserve recorded significant carbon gain during 60% of the drought period.","PeriodicalId":50085,"journal":{"name":"Journal of Plant Ecology","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48155983","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}
Yaowen Zhang, Yunlong Zhang, T. Huo, Bin Wei, Kangli Chen, Nan Liu, Yingjun Zhang, Junyi Liang
Grazing exclusion using fencing has been considered an effective means of vegetation restoration in degraded grasslands. Increased plant growth during recovery requires more nitrogen (N), which is a major limiting factor in northern China. It remains unclear whether soil N supply in this region can support long-term vegetation restoration. In this study, a field inventory was conducted in seven temperate grasslands in northern China. At each site, grassland outside of the fencing experienced continuous grazing, whereas that within the fencing was protected. Results showed that grazing exclusion significantly increased aboveground biomass, species richness, and the Shannon–Wiener diversity index by 126.2%, 42.6%, and 18.8%, respectively. Grazing exclusion reduced the concentrations of nitrate and total inorganic N by 51.9% and 21.0%, respectively, suggesting that there may be a mismatch between N supply and plant demand during the growing season. The aboveground biomass, species richness, and Shannon–Wiener diversity index in the restored grasslands were positively correlated with legume dominance within the community. These results indicate that the vegetation restoration in temperate grasslands could be constrained by soil N availability, which may be supplemented through biological N fixation.
{"title":"Vegetation Restoration Constrained by Nitrogen Availability in Temperate Grasslands in Northern China","authors":"Yaowen Zhang, Yunlong Zhang, T. Huo, Bin Wei, Kangli Chen, Nan Liu, Yingjun Zhang, Junyi Liang","doi":"10.1093/jpe/rtac087","DOIUrl":"https://doi.org/10.1093/jpe/rtac087","url":null,"abstract":"\u0000 Grazing exclusion using fencing has been considered an effective means of vegetation restoration in degraded grasslands. Increased plant growth during recovery requires more nitrogen (N), which is a major limiting factor in northern China. It remains unclear whether soil N supply in this region can support long-term vegetation restoration. In this study, a field inventory was conducted in seven temperate grasslands in northern China. At each site, grassland outside of the fencing experienced continuous grazing, whereas that within the fencing was protected. Results showed that grazing exclusion significantly increased aboveground biomass, species richness, and the Shannon–Wiener diversity index by 126.2%, 42.6%, and 18.8%, respectively. Grazing exclusion reduced the concentrations of nitrate and total inorganic N by 51.9% and 21.0%, respectively, suggesting that there may be a mismatch between N supply and plant demand during the growing season. The aboveground biomass, species richness, and Shannon–Wiener diversity index in the restored grasslands were positively correlated with legume dominance within the community. These results indicate that the vegetation restoration in temperate grasslands could be constrained by soil N availability, which may be supplemented through biological N fixation.","PeriodicalId":50085,"journal":{"name":"Journal of Plant Ecology","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45794286","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}
Yumeng Guo, Meng Zhou, J. Sheng, Yujia Yuan, Guangyuan Yuan, Wen‐Hao Zhang, Wenming Bai
Phosphorus (P) is an essential element for plant growth, however, whether the aboveground net primary productivity (ANPP) of typical steppe was limited by P remains obscure. To detect the effects of P addition on primary productivity and aboveground biomass of different plant functional groups both under ambient and N addition conditions, ANPP and aboveground biomass of grasses and forbs were measured from 2016 to 2020 on a 16-year N and P addition experiment platform in a temperate typical steppe in Inner Mongolia. The soil available N and P concentration were also determined to test the relationship between ANPP and the availability of soil nutrient. We found that P addition under ambient condition had no significant effect on ANPP and the aboveground biomass of grasses and forbs. Whereas, under N addition, P addition significantly increased ANPP and the aboveground biomass of forbs. Furthermore, soil available N and P concentration were increased significantly by N and P addition, respectively. Moreover, there was no significant correlation between ANPP and soil available P concentration, while, ANPP was positively correlated with soil available N concentration. These results suggested that P was not the key factor limiting the primary productivity of the temperate typical steppe in Inner Mongolia. However, under N addition, P addition can promote ANPP and alter the community composition. These findings provide valuable information for the management of the temperate typical steppe.
{"title":"Aboveground net primary productivity was not limited by phosphorus in a temperate typical steppe in Inner Mongolia","authors":"Yumeng Guo, Meng Zhou, J. Sheng, Yujia Yuan, Guangyuan Yuan, Wen‐Hao Zhang, Wenming Bai","doi":"10.1093/jpe/rtac085","DOIUrl":"https://doi.org/10.1093/jpe/rtac085","url":null,"abstract":"\u0000 Phosphorus (P) is an essential element for plant growth, however, whether the aboveground net primary productivity (ANPP) of typical steppe was limited by P remains obscure. To detect the effects of P addition on primary productivity and aboveground biomass of different plant functional groups both under ambient and N addition conditions, ANPP and aboveground biomass of grasses and forbs were measured from 2016 to 2020 on a 16-year N and P addition experiment platform in a temperate typical steppe in Inner Mongolia. The soil available N and P concentration were also determined to test the relationship between ANPP and the availability of soil nutrient. We found that P addition under ambient condition had no significant effect on ANPP and the aboveground biomass of grasses and forbs. Whereas, under N addition, P addition significantly increased ANPP and the aboveground biomass of forbs. Furthermore, soil available N and P concentration were increased significantly by N and P addition, respectively. Moreover, there was no significant correlation between ANPP and soil available P concentration, while, ANPP was positively correlated with soil available N concentration. These results suggested that P was not the key factor limiting the primary productivity of the temperate typical steppe in Inner Mongolia. However, under N addition, P addition can promote ANPP and alter the community composition. These findings provide valuable information for the management of the temperate typical steppe.","PeriodicalId":50085,"journal":{"name":"Journal of Plant Ecology","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49628786","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}
Pesticides are widely used to enhance food production on a global scale. However, little information is available on the effects of pesticide application on leaf physiology and phyllosphere bacterial communities of dioecious plants. Therefore, this study aimed to assess the impact of λ-cyhalothrin, a broad-spectrum pesticide, on leaf physiology and phyllosphere bacterial communities in the dioecious Populus cathayana. Physiological leaf traits such as photosynthetic apparatus (net photosynthetic rate (Pn), stomatal conductance (gs), and transpiration (E)) of males were significantly higher than those of females, independent of pesticide use. In contrast, pesticide application significantly reduced the photosynthetic apparatus for both sexes, and the reduction was greater in males relative to females. Also, pesticide application significantly increased peroxidase (POD) activity and malondialdehyde (MDA) content and maintained superoxide dismutase (SOD) activity and total chlorophyll content in leaves of males. The phyllosphere bacteria showed some conserved characteristics, in which, Simpson and Shannon diversity indices were not affected by sex or pesticide application. Phyllosphere bacterial community composition differed between females and males indicating that intrinsic sex significantly shaped the phyllosphere bacteria community. However, pesticide application significantly increased the relative abundance of Actinobacteria but reduced the relative abundance of Proteobacteria. Principal component analysis showed associations between leaf physiology and specific bacterial taxa. For instance, Proteobacteria negatively correlated with leaf SOD activity and MDA content, while Actinobacteria showed an opposite pattern. Our study highlights sex-specific phyllosphere bacterial community composition and leaf physiological traits in dioecious plants.
{"title":"Effects of pesticide application and plant sexual identity on leaf physiological traits and phyllosphere bacterial communities","authors":"Zuodong Zhu, Yue He, Jiahui Xu, Zhenghu Zhou, Amit Kumar, Zhichao Xia","doi":"10.1093/jpe/rtac084","DOIUrl":"https://doi.org/10.1093/jpe/rtac084","url":null,"abstract":"\u0000 Pesticides are widely used to enhance food production on a global scale. However, little information is available on the effects of pesticide application on leaf physiology and phyllosphere bacterial communities of dioecious plants. Therefore, this study aimed to assess the impact of λ-cyhalothrin, a broad-spectrum pesticide, on leaf physiology and phyllosphere bacterial communities in the dioecious Populus cathayana. Physiological leaf traits such as photosynthetic apparatus (net photosynthetic rate (Pn), stomatal conductance (gs), and transpiration (E)) of males were significantly higher than those of females, independent of pesticide use. In contrast, pesticide application significantly reduced the photosynthetic apparatus for both sexes, and the reduction was greater in males relative to females. Also, pesticide application significantly increased peroxidase (POD) activity and malondialdehyde (MDA) content and maintained superoxide dismutase (SOD) activity and total chlorophyll content in leaves of males. The phyllosphere bacteria showed some conserved characteristics, in which, Simpson and Shannon diversity indices were not affected by sex or pesticide application. Phyllosphere bacterial community composition differed between females and males indicating that intrinsic sex significantly shaped the phyllosphere bacteria community. However, pesticide application significantly increased the relative abundance of Actinobacteria but reduced the relative abundance of Proteobacteria. Principal component analysis showed associations between leaf physiology and specific bacterial taxa. For instance, Proteobacteria negatively correlated with leaf SOD activity and MDA content, while Actinobacteria showed an opposite pattern. Our study highlights sex-specific phyllosphere bacterial community composition and leaf physiological traits in dioecious plants.","PeriodicalId":50085,"journal":{"name":"Journal of Plant Ecology","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46310399","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}
Tongrui Zhang, F. Li, Lin Wu, Hao-Yun Wang, Yanlong Li, C. Shi
Nutrient resorption in autumn is a key mechanism of perennial plants for nutrient conservation and efficient use in grassland. Grazing effects on plant nutrient resorption may alter root nutrient conservation and affect plant growth in the subsequent spring. There are many studies on nutrient resorption and conservation of plants in grazing grassland, but few studies on its effect on plant growth in subsequent spring. Taking Stipa grandis, a dominant perennial grass in a semi-arid steppe as a model plant, we examined plant nitrogen (N) and phosphorous (P) resorption traits (resorption efficiency, proficiency and flux) and root nutrient conservation traits (root biomass and nutrient pool) in autumn, and plant growth traits (height, biomass and nutrient pool) in the subsequent spring, in an experimental grassland under four grazing-season treatments (i.e., grazing in spring, summer or autumn, or no grazing). We found that (1) 51-66% of N and 58-80% of P in S. grandis shoots were resorbed in autumn, and the resorption flux was the lowest under autumn grazing, and highest under spring grazing. (2) Root nutrient conservation traits were significantly reduced by summer grazing, slightly decreased by spring grazing, but not affected by autumn grazing. (3) Plant growth in next spring was the best under early spring grazing and the worst under autumn grazing, which was mainly affected by soil moisture rather than root nutrient storage. Our study provides insights into the process of plant nutrient cycling and a theoretical basis for establishing grazing system for grassland protection and rational utilization.
{"title":"Seasonal grazing alters nutrient resorption and conservation, and affects spring growth of Stipa grandis","authors":"Tongrui Zhang, F. Li, Lin Wu, Hao-Yun Wang, Yanlong Li, C. Shi","doi":"10.1093/jpe/rtac083","DOIUrl":"https://doi.org/10.1093/jpe/rtac083","url":null,"abstract":"\u0000 Nutrient resorption in autumn is a key mechanism of perennial plants for nutrient conservation and efficient use in grassland. Grazing effects on plant nutrient resorption may alter root nutrient conservation and affect plant growth in the subsequent spring. There are many studies on nutrient resorption and conservation of plants in grazing grassland, but few studies on its effect on plant growth in subsequent spring. Taking Stipa grandis, a dominant perennial grass in a semi-arid steppe as a model plant, we examined plant nitrogen (N) and phosphorous (P) resorption traits (resorption efficiency, proficiency and flux) and root nutrient conservation traits (root biomass and nutrient pool) in autumn, and plant growth traits (height, biomass and nutrient pool) in the subsequent spring, in an experimental grassland under four grazing-season treatments (i.e., grazing in spring, summer or autumn, or no grazing). We found that (1) 51-66% of N and 58-80% of P in S. grandis shoots were resorbed in autumn, and the resorption flux was the lowest under autumn grazing, and highest under spring grazing. (2) Root nutrient conservation traits were significantly reduced by summer grazing, slightly decreased by spring grazing, but not affected by autumn grazing. (3) Plant growth in next spring was the best under early spring grazing and the worst under autumn grazing, which was mainly affected by soil moisture rather than root nutrient storage. Our study provides insights into the process of plant nutrient cycling and a theoretical basis for establishing grazing system for grassland protection and rational utilization.","PeriodicalId":50085,"journal":{"name":"Journal of Plant Ecology","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48415329","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}
Plant–arbuscular mycorrhizal fungal (AMF) associations can mediate soil resources among competing plants to influence plant resource capture and fitness, making AMF a potential agent of plant coexistence. We assessed plant coexistence, via niche and fitness differences, using six plant species varying in their mycorrhizal status. We grew the species in 15 competitive pairs with or without AMF. Effects of AMF on coexistence were determined by parametrising pairwise Lotka–Volterra plant competition models. Responses of the six plant species to AMF were determined by comparing the shoot biomass of single plants grown in the absence of any competition with AMF to the shoot biomass without AMF. The inoculation with AMF reduced the fitness differences between competitors, but the degree of AMF-mediated coexistence depended on the identity of the competing plant species. A greater AMF response difference between competing plant species reduced niche overlap and increased coexistence. These results show that while AMF generally reduce fitness differences, the equalizing effect of AMF is not always strong enough to overcome a competitive imbalance due to niche overlap and thus does not always lead to coexistence. Instead, it is the intrinsic growth response of different plant species to AMF can predict reduced niche overlap that in turn leads to coexistence. This implies that mycorrhizal dependence is a plant strategy to reduce niche overlap with competitors allowing for greater coexistence.
{"title":"Mycorrhizal fungi reduce fitness differences, but coexistence is determined by differences in intrinsic plant mycorrhizal responsiveness","authors":"C. Wagg, A. McKenzie‐Gopsill","doi":"10.1093/jpe/rtac081","DOIUrl":"https://doi.org/10.1093/jpe/rtac081","url":null,"abstract":"\u0000 Plant–arbuscular mycorrhizal fungal (AMF) associations can mediate soil resources among competing plants to influence plant resource capture and fitness, making AMF a potential agent of plant coexistence. We assessed plant coexistence, via niche and fitness differences, using six plant species varying in their mycorrhizal status. We grew the species in 15 competitive pairs with or without AMF. Effects of AMF on coexistence were determined by parametrising pairwise Lotka–Volterra plant competition models. Responses of the six plant species to AMF were determined by comparing the shoot biomass of single plants grown in the absence of any competition with AMF to the shoot biomass without AMF. The inoculation with AMF reduced the fitness differences between competitors, but the degree of AMF-mediated coexistence depended on the identity of the competing plant species. A greater AMF response difference between competing plant species reduced niche overlap and increased coexistence. These results show that while AMF generally reduce fitness differences, the equalizing effect of AMF is not always strong enough to overcome a competitive imbalance due to niche overlap and thus does not always lead to coexistence. Instead, it is the intrinsic growth response of different plant species to AMF can predict reduced niche overlap that in turn leads to coexistence. This implies that mycorrhizal dependence is a plant strategy to reduce niche overlap with competitors allowing for greater coexistence.","PeriodicalId":50085,"journal":{"name":"Journal of Plant Ecology","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45437337","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}
{"title":"A new system for distinguishing native from exotic species in China","authors":"Song-Zhi Xu, Han Xu, Caiyun Zhao, Zhen-Yu Li","doi":"10.1093/jpe/rtac080","DOIUrl":"https://doi.org/10.1093/jpe/rtac080","url":null,"abstract":"","PeriodicalId":50085,"journal":{"name":"Journal of Plant Ecology","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48101447","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}
Pei Zheng, R. Zhao, Liangchao Jiang, Guojiao Yang, Yinliu Wang, Ruzhen Wang, Xingguo Han, Qiushi Ning
Plant litter decomposition is critical for the carbon (C) balance and nutrient turnover in terrestrial ecosystems and sensitive to the ongoing anthropogenic nitrogen (N) input. Previous studies evaluating the N effect on litter decomposition relied mostly on short-term experiments (< 2 years), which probably masked the real N effect on litter decomposition. Therefore, long-lasting experiments are imperative for the overall evaluation of the litter decomposition dynamics under N enrichment. We conducted a long-term (4-year) N addition experiment with N levels from 0 – 50 g N m -2 yr -1 to examine the potential abiotic and biotic factors in regulating the decomposition process of litterfall from the dominant species Leymus chinensis. The long-term experiment exhibited a consistent decrease of decomposition rate with increasing N addition rates, providing strong evidence showing the inhibitory effect of N addition on decomposition. The N-induced alterations in soil environment (acidification and nutrient stoichiometry), microbial activity (microbial biomass and enzyme activity), changes of litter quality (residual lignin and nutrient content) and plant community (aboveground productivity and species richness) jointly contributed to the lowered decomposition. During the whole decomposition process, the changes of litter quality, including accumulation of lignin and the concentrations of nutrient, were mainly driven by the soil environment and microbial activity in this N-enriched environment. The findings help clarify how increasing N input rates affect long-term litter decomposition, and improve the mechanistic understanding of the linkages between ecosystem N enrichment and C cycling.
植物凋落物分解对陆地生态系统碳(C)平衡和养分周转至关重要，对持续的人为氮(N)输入非常敏感。以往评价N对凋落物分解影响的研究大多依赖于短期实验(< 2年)，这可能掩盖了N对凋落物分解的真实影响。因此，长期实验是全面评价富氮条件下凋落物分解动态的必要条件。为了研究优势种羊草凋落物分解过程中可能存在的非生物和生物因素，我们进行了长期(4年)N添加试验，N水平为0 ~ 50 g N m -2 yr -1。长期实验显示，随着N添加量的增加，分解速率一致降低，为N添加对分解的抑制作用提供了强有力的证据。氮诱导的土壤环境(酸化和养分化学计量)、微生物活性(微生物生物量和酶活性)、凋落物质量(残余木质素和养分含量)和植物群落(地上生产力和物种丰富度)的变化共同导致了分解的降低。在整个分解过程中，凋落物质量的变化，包括木质素积累和养分浓度的变化，主要受土壤环境和富氮环境下微生物活动的驱动。这些发现有助于阐明增加N输入率如何影响凋落物的长期分解，并提高对生态系统N富集与C循环之间联系的机制理解。
{"title":"Increasing nitrogen addition rates suppressed long-term litter decomposition in a temperate meadow steppe","authors":"Pei Zheng, R. Zhao, Liangchao Jiang, Guojiao Yang, Yinliu Wang, Ruzhen Wang, Xingguo Han, Qiushi Ning","doi":"10.1093/jpe/rtac078","DOIUrl":"https://doi.org/10.1093/jpe/rtac078","url":null,"abstract":"\u0000 Plant litter decomposition is critical for the carbon (C) balance and nutrient turnover in terrestrial ecosystems and sensitive to the ongoing anthropogenic nitrogen (N) input. Previous studies evaluating the N effect on litter decomposition relied mostly on short-term experiments (< 2 years), which probably masked the real N effect on litter decomposition. Therefore, long-lasting experiments are imperative for the overall evaluation of the litter decomposition dynamics under N enrichment. We conducted a long-term (4-year) N addition experiment with N levels from 0 – 50 g N m -2 yr -1 to examine the potential abiotic and biotic factors in regulating the decomposition process of litterfall from the dominant species Leymus chinensis. The long-term experiment exhibited a consistent decrease of decomposition rate with increasing N addition rates, providing strong evidence showing the inhibitory effect of N addition on decomposition. The N-induced alterations in soil environment (acidification and nutrient stoichiometry), microbial activity (microbial biomass and enzyme activity), changes of litter quality (residual lignin and nutrient content) and plant community (aboveground productivity and species richness) jointly contributed to the lowered decomposition. During the whole decomposition process, the changes of litter quality, including accumulation of lignin and the concentrations of nutrient, were mainly driven by the soil environment and microbial activity in this N-enriched environment. The findings help clarify how increasing N input rates affect long-term litter decomposition, and improve the mechanistic understanding of the linkages between ecosystem N enrichment and C cycling.","PeriodicalId":50085,"journal":{"name":"Journal of Plant Ecology","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43063320","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}
Snow cover changes in temperate desert ecosystems influence plant diversity, richness, and distribution. The growth and distribution of herbaceous plants in these ecosystems are closely related to snow-cover depth, the most important water resource during the growth period due to water shortage during the dry season. However, the response to snow cover change in winter remains unclear. The present investigation was undertaken to examine the influence of snow cover change on the root growth of herbaceous species. The growth of desert typical ephemeral species, Erodium oxyrrhinchum was examined in Gurbantunggut Desert with four snow cover depth treatments in winter. The four treatments were snow removal (−S), ambient snow, double snow (+S), and triple snow (+2S). The snow depth addition increased the abundance and growth rate of herbaceous plants. It also enhanced the biomass (including total and individual biomass) of these plants. The leaf area (LA) of E. oxyrrhinchum increased significantly with snow addition, and the leaf dry matter content (LDMC) had an opposite trend. The study showed that the above-ground section of the plant was more sensitive to snow change than the underground. Snow change also influenced the root morphology. Snow remove resulted in the emergence of more lateral root, whereas snow addition promoted the elongation of the main root for water and nutrient absorption. These results explain how changes in winter snow cover depth alter plant growth, community structure, and ecosystem function during the growing period in temperate desert ecosystems.
{"title":"Typical Ephemeral Plant -Erodium oxyrrhinchum: Growth Response to Snow Change in Temperate Desert, Northwest China","authors":"Jin-fei Yin, Xiaobing Zhou, N. Wu, Yuanming Zhang","doi":"10.1093/jpe/rtac079","DOIUrl":"https://doi.org/10.1093/jpe/rtac079","url":null,"abstract":"\u0000 Snow cover changes in temperate desert ecosystems influence plant diversity, richness, and distribution. The growth and distribution of herbaceous plants in these ecosystems are closely related to snow-cover depth, the most important water resource during the growth period due to water shortage during the dry season. However, the response to snow cover change in winter remains unclear. The present investigation was undertaken to examine the influence of snow cover change on the root growth of herbaceous species. The growth of desert typical ephemeral species, Erodium oxyrrhinchum was examined in Gurbantunggut Desert with four snow cover depth treatments in winter. The four treatments were snow removal (−S), ambient snow, double snow (+S), and triple snow (+2S). The snow depth addition increased the abundance and growth rate of herbaceous plants. It also enhanced the biomass (including total and individual biomass) of these plants. The leaf area (LA) of E. oxyrrhinchum increased significantly with snow addition, and the leaf dry matter content (LDMC) had an opposite trend. The study showed that the above-ground section of the plant was more sensitive to snow change than the underground. Snow change also influenced the root morphology. Snow remove resulted in the emergence of more lateral root, whereas snow addition promoted the elongation of the main root for water and nutrient absorption. These results explain how changes in winter snow cover depth alter plant growth, community structure, and ecosystem function during the growing period in temperate desert ecosystems.","PeriodicalId":50085,"journal":{"name":"Journal of Plant Ecology","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43696479","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}
{"title":"JPE Best Paper awards (2020)","authors":"Wen-Hao Zhang, B. Schmid","doi":"10.1093/jpe/rtac076","DOIUrl":"https://doi.org/10.1093/jpe/rtac076","url":null,"abstract":"","PeriodicalId":50085,"journal":{"name":"Journal of Plant Ecology","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46605612","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}
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