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Sun H, Su X, Jin L, Li C, Kou J, Zhang J, Li X. Response of Carbon-Fixing Bacteria to Patchy Degradation of the Alpine Meadow in the Source Zone of the Yellow River, West China. PLANTS (BASEL, SWITZERLAND) 2024; 13:579. [PMID: 38475426 DOI: 10.3390/plants13050579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 02/01/2024] [Accepted: 02/06/2024] [Indexed: 03/14/2024]
Abstract
This study aims to enlighten our understanding of the distribution of soil carbon-fixing bacteria (cbbL-harboring bacteria) and their community diversity in differently degraded patches at three altitudes. MiSeq high-throughput sequencing technology was used to analyze the soil carbon-fixing bacteria community diversity of degraded patches and healthy meadow at three altitudes. Redundancy analysis (RDA) and structural equation model (SEM) were used to analyze the correlation and influence path between environmental factors and carbon-fixing bacteria. The results showed that degradation reduced the relative abundance of Proteobacteria from 99.67% to 95.57%. Sulfurifustis, Cupriavidus, and Alkalispirillum were the dominant genera at the three altitudes. Hydrogenophaga and Ectothiorhodospira changed significantly with altitude. RDA results confirmed that available phosphorus (AP) was strongly and positively correlated with Proteobacteria. AP and total nitrogen (TN) were strongly and positively correlated with Hydrogenophaga. Grass coverage and sedge aboveground biomass were strongly and positively correlated with Sulfurifustis and Ectothiorhodospira, respectively. Elevation adversely affected the relative abundance of dominant carbon-fixing bacteria and diversity index by reducing the coverage of grass and soil volumetric moisture content (SVMC) indirectly, and also had a direct positive impact on the Chao1 index (path coefficient = 0.800). Therefore, increasing the content of nitrogen, phosphorus and SVMC and vegetation coverage, especially sedge and grass, will be conducive to the recovery of the diversity of soil carbon-fixing bacteria and improve the soil autotrophic microbial carbon sequestration potential in degraded meadows, especially in high-altitude areas.
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Affiliation(s)
- Huafang Sun
- State Key Laboratory of Plateau Ecology and Agriculture, College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, China
- College of Eco-Environment and Resources, Qinghai University for Nationalities, Xining 810007, China
| | - Xiaoxue Su
- State Key Laboratory of Plateau Ecology and Agriculture, College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, China
| | - Liqun Jin
- State Key Laboratory of Plateau Ecology and Agriculture, College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, China
| | - Chengyi Li
- State Key Laboratory of Plateau Ecology and Agriculture, College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, China
| | - Jiancun Kou
- College of Grassland Agriculture, Northwest A&F University, Yangling 712100, China
| | - Jing Zhang
- State Key Laboratory of Plateau Ecology and Agriculture, College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, China
| | - Xilai Li
- State Key Laboratory of Plateau Ecology and Agriculture, College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, China
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Song S, Xiong K, Chi Y. Response of grassland ecosystem function to plant functional traits under different vegetation restoration models in areas of karst desertification. FRONTIERS IN PLANT SCIENCE 2023; 14:1239190. [PMID: 38148857 PMCID: PMC10749941 DOI: 10.3389/fpls.2023.1239190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 11/20/2023] [Indexed: 12/28/2023]
Abstract
Plant functional traits serve as a bridge between plants, the environment, and ecosystem function, playing an important role in predicting the changes in ecosystem function that occur during ecological restoration. However, the response of grassland ecosystem function to plant functional traits in the context of ecological restoration in areas of karst desertification remains unclear. Therefore, in this study, we selected five plant functional traits [namely, plant height (H), specific leaf area (SLA), leaf dry matter content (LDMC), root length (RL), and root dry matter content (RDMC)], measured these along with community-weighted mean (CWM) and functional trait diversity, and combined these measures with 10 indexes related to ecosystem function in order to investigate the differences in plant functional traits and ecosystem function, as well as the relationship between plant functional traits and ecosystem functions, under four ecological restoration models [Dactylis glomerata (DG), Lolium perenne (LP), Lolium perenne + Trifolium repens (LT), and natural grassland (NG)]. We found that: 1) the Margalef index and Shannon-Wiener index were significantly lower for plant species in DG and LP than for those in NG (P<0.05), while the Simpson index was significantly higher in the former than in NG (P<0.05); 2) CWMH, CWMLDMC, and CWMRDMC were significantly higher in DG, LP, and LT than in NG, while CWMSLA was significantly lower in the former than in NG (P<0.05). The functional richness index (FRic) was significantly higher in DG and LP than in NG and LT, but the functional dispersion index (FDis) and Rao's quadratic entropy index (RaoQ) were significantly lower in DG and LP than in NG and LT (P<0.05), and there was no significant difference between DG and LP, or between NG and LT (P>0.05); 3) ecosystem function, including ecosystem productivity, carbon storage, water conservation and soil conservation, was highest in LT and lowest in NG; and 4) CWMLDMC (F=56.7, P=0.024), CWMRL (F=28.7, P=0.024), and CWMH (F=4.5, P=0.048) were the main factors affecting ecosystem function. The results showed that the mixed pasture of perennial ryegrass and white clover was most conductive to restoration of ecosystem function. This discovery has important implications for the establishment of vegetation, optimal utilization of resources, and the sustainable development of degraded karst ecosystems.
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Affiliation(s)
- Shuzhen Song
- School of Karst Science, Guizhou Normal University, Guiyang, China
| | - Kangning Xiong
- State Engineering Technology Institute for Karst Desertification Control, Guizhou Normal University, Guiyang, China
| | - Yongkuan Chi
- School of Karst Science, Guizhou Normal University, Guiyang, China
- State Engineering Technology Institute for Karst Desertification Control, Guizhou Normal University, Guiyang, China
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Yang C, Zhang H, Zhao X, Liu P, Wang L, Wang W. A functional metagenomics study of soil carbon and nitrogen degradation networks and limiting factors on the Tibetan plateau. Front Microbiol 2023; 14:1170806. [PMID: 37228377 PMCID: PMC10203874 DOI: 10.3389/fmicb.2023.1170806] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 04/10/2023] [Indexed: 05/27/2023] Open
Abstract
Introduction The Three-River Source Nature Reserve is located in the core area of the Qinghai-Tibetan Plateau, with the alpine swamp, meadow and steppe as the main ecosystem types. However, the microbial communities in these alpine ecosystems, and their carbon and nitrogen degrading metabolic networks and limiting factors remain unclear. Methods We sequenced the diversity of bacteria and fungi in alpine swamps, meadows, steppes, and their degraded and artificially restored ecosystems and analyzed soil environmental conditions. Results The results indicated that moisture content had a greater influence on soil microbial community structure compared to degradation and restoration. Proteobacteria dominated in high moisture alpine swamps and alpine meadows, while Actinobacteria dominated in low moisture alpine steppes and artificial grasslands. A metabolic network analysis of carbon and nitrogen degradation and transformation using metagenomic sequencing revealed that plateau microorganisms lacked comprehensive and efficient enzyme systems to degrade organic carbon, nitrogen, and other biological macromolecules, so that the short-term degradation of alpine vegetation had no effect on the basic composition of soil microbial community. Correlation analysis found that nitrogen fixation was strong in meadows with high moisture content, and their key nitrogen-fixing enzymes were significantly related to Sphingomonas. Denitrification metabolism was enhanced in water-deficient habitats, and the key enzyme, nitrous oxide reductase, was significantly related to Phycicoccus and accelerated the loss of nitrogen. Furthermore, Bacillus contained a large number of amylases (GH13 and GH15) and proteases (S8, S11, S26, and M24) which may promote the efficient degradation of organic carbon and nitrogen in artificially restored grasslands. Discussion This study illustrated the irrecoverability of meadow degradation and offered fundamental information for altering microbial communities to restore alpine ecosystems.
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Affiliation(s)
- Chong Yang
- School of Geographical Sciences, Qinghai Normal University, Xining, China
- School of Life Sciences, Qinghai Normal University, Xining, China
| | - Hong Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Xinquan Zhao
- Northwest Plateau Institute of Biology, Chinese Academy of Sciences, Xining, China
| | - Pan Liu
- School of Geographical Sciences, Qinghai Normal University, Xining, China
| | - Lushan Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Wenying Wang
- School of Life Sciences, Qinghai Normal University, Xining, China
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Jiang C, Zhao J, Ding Y, Li G. Vis-NIR Spectroscopy Combined with GAN Data Augmentation for Predicting Soil Nutrients in Degraded Alpine Meadows on the Qinghai-Tibet Plateau. SENSORS (BASEL, SWITZERLAND) 2023; 23:3686. [PMID: 37050746 PMCID: PMC10098562 DOI: 10.3390/s23073686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/22/2023] [Accepted: 03/29/2023] [Indexed: 06/19/2023]
Abstract
Soil nutrients play vital roles in vegetation growth and are a key indicator of land degradation. Accurate, rapid, and non-destructive measurement of the soil nutrient content is important for ecological conservation, degradation monitoring, and precision farming. Currently, visible and near-infrared (Vis-NIR) spectroscopy allows for rapid and non-destructive monitoring of soil nutrients. However, the performance of Vis-NIR inversion models is extremely dependent on the number of samples. Limited samples may lead to low prediction accuracy of the models. Therefore, modeling and prediction based on a small sample size remain a challenge. This study proposes a method for the simultaneous augmentation of soil spectral and nutrient data (total nitrogen (TN), soil organic matter (SOM), total potassium oxide (TK2O), and total phosphorus pentoxide (TP2O5)) using a generative adversarial network (GAN). The sample augmentation range and the level of accuracy improvement were also analyzed. First, 42 soil samples were collected from the pika disturbance area on the QTP. The collected soils were measured in the laboratory for Vis-NIR and TN, SOM, TK2O, and TP2O5 data. A GAN was then used to augment the soil spectral and nutrient data simultaneously. Finally, the effect of adding different numbers of generative samples to the training set on the predictive performance of a convolutional neural network (CNN) was analyzed and compared with another data augmentation method (extended multiplicative signal augmentation, EMSA). The results showed that a GAN can generate data very similar to real data and with better diversity. A total of 15, 30, 60, 120, and 240 generative samples (GAN and EMSA) were randomly selected from 300 generative samples to be included in the real data to train the CNN model. The model performance first improved and then deteriorated, and the GAN was more effective than EMSA. Further shortening the interval for adding GAN data revealed that the optimal ranges were 30-40, 50-60, 30-35, and 25-35 for TK2O, TN, TP2O5, and SOM, respectively, and the validation set accuracy was maximized in these ranges. Therefore, the above method can compensate to some extent for insufficient samples in the hyperspectral prediction of soil nutrients, and can quickly and accurately estimate the content of soil TK2O, TN, TP2O5, and SOM.
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Affiliation(s)
- Chuanli Jiang
- Department of Geologic Engineering, Qinghai University, Xining 810016, China
| | - Jianyun Zhao
- Department of Geologic Engineering, Qinghai University, Xining 810016, China
- Key Lab of Cenozoic Resource & Environment in North Margin of the Tibetan Plateau, Xining 810016, China
| | - Yuanyuan Ding
- Department of Geologic Engineering, Qinghai University, Xining 810016, China
| | - Guorong Li
- Department of Geologic Engineering, Qinghai University, Xining 810016, China
- Key Lab of Cenozoic Resource & Environment in North Margin of the Tibetan Plateau, Xining 810016, China
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Jiang C, Sun X, Liu Y, Zhu S, Wu K, Li H, Shui W. Karst tiankeng shapes the differential composition and structure of bacterial and fungal communities in karst land. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:32573-32584. [PMID: 36469271 DOI: 10.1007/s11356-022-24229-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 11/11/2022] [Indexed: 06/17/2023]
Abstract
Karst tiankeng are important biodiversity conservation reservoirs. However, the unique habitats of karst tiankeng affect microbial community structure remained poorly understood. In this study, we collected soil samples from karst tiankeng (TK) and karst land (KL) and subjected to high-throughput sequencing. Based on the classification of the total, abundance, and rare taxa for bacteria and fungi, a multivariate statistical analysis was carried out. The results revealed that bacterial community Shannon diversity and Pielou's evenness were highest in TK. The rare taxa were ubiquitous in all soil samples, while the higher Shannon diversity of the abundant taxa of TK may be related to the habitat preferences of species and niche differentiation. The community composition of bacterial and fungal sub-communities exhibited significant dissimilarity between TK and KL. The redundancy analysis further demonstrated that abundant taxa were environmentally more constrained than rare taxa. The bacterial and fungal networks of KL were more complex than TK. The keystones of the network transforms may suggest their significant role in the ecological function of the karst tiankeng ecosystem. This study represents the first reports of the characteristics of bacterial and fungal communities in karst tiankeng.
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Affiliation(s)
- Cong Jiang
- College of Urban and Environmental Sciences, Peking University, Beijing, 100871, People's Republic of China
| | - Xiang Sun
- College of Environment and Safety Engineering, Fujian Province, Fuzhou University, Fuzhou University Town, No. 2 Wulongjiang North Avenue, Fuzhou City, People's Republic of China
| | - Yuanmeng Liu
- College of Environment and Safety Engineering, Fujian Province, Fuzhou University, Fuzhou University Town, No. 2 Wulongjiang North Avenue, Fuzhou City, People's Republic of China
| | - Sufeng Zhu
- Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, 100871, People's Republic of China
| | - Kexing Wu
- College of Environment and Safety Engineering, Fujian Province, Fuzhou University, Fuzhou University Town, No. 2 Wulongjiang North Avenue, Fuzhou City, People's Republic of China
| | - Hui Li
- College of Environment and Safety Engineering, Fujian Province, Fuzhou University, Fuzhou University Town, No. 2 Wulongjiang North Avenue, Fuzhou City, People's Republic of China
| | - Wei Shui
- College of Environment and Safety Engineering, Fujian Province, Fuzhou University, Fuzhou University Town, No. 2 Wulongjiang North Avenue, Fuzhou City, People's Republic of China.
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Wang N, Wan J, Ding M, Zhang H, Li S, Liu L, Zhang Y. More management is needed to improve the effectiveness of artificial grassland in vegetation and soil restoration on the three-river headwaters region of China. FRONTIERS IN PLANT SCIENCE 2023; 14:1152405. [PMID: 37152120 PMCID: PMC10161201 DOI: 10.3389/fpls.2023.1152405] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 04/04/2023] [Indexed: 05/09/2023]
Abstract
Establishing an artificial grassland is a common measure employed to restore heavily degraded alpine grasslands for regional sustainability. The Three-River Headwaters Region in China has significant areas of black-soil-type grassland which is typified by heavy degradation; nearly 35% of the grassland regions in the Three-River Headwaters Region has degraded into this type. There are different plant community types of black-soil-type grasslands, however, it is not clear which restoration measures should be adopted for different kinds of black-soil-type grasslands. Here, we investigate the plant community characteristics and soil physicochemical properties of artificial grasslands, two types of black-soil-type grasslands, and native undegraded grassland in the Three-River Headwaters Region, then analyzed the direct and indirect interactions between the plant and soil properties by partial least squares path models (PLS-PM). Our results revealed that establishing artificial grassland significantly increased aboveground biomass and plant community coverage, and also decreased plant species richness and diversity and soil water content, soil organic carbon and total nitrogen in the 0-10 cm soil layer as compared with black-soil-type grasslands. Plant community diversity had a positive effect on plant community productivity, soil nutrient, and soil water content in native undegraded grassland. These results suggest that more management interventions are needed after establishing an artificial grassland, such as reducing dominant species in two types of black-soil-type grasslands, water regulation in the A. frigida-dominated meadow, diversifying plant species (i.e., Gramineae and sedges), and fertilizer addition.
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Affiliation(s)
- Nengyu Wang
- School of Geography and Environment, Jiangxi Normal University, Nanchang, China
| | - Jiayi Wan
- School of Geography and Environment, Jiangxi Normal University, Nanchang, China
| | - Mingjun Ding
- School of Geography and Environment, Jiangxi Normal University, Nanchang, China
- Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang, China
- *Correspondence: Mingjun Ding,
| | - Hua Zhang
- School of Geography and Environment, Jiangxi Normal University, Nanchang, China
- Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang, China
| | - Shicheng Li
- Department of Land Resource Management, School of Public Administration, China University of Geosciences, Wuhan, China
| | - Linshan Liu
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Science and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Yili Zhang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Science and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
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Zhou X, Xiao Y, Ma D, Xie Y, Wang Y, Zhang H, Wang Y. The competitive strategies of poisonous weeds Elsholtzia densa Benth. on the Qinghai Tibet Plateau: Allelopathy and improving soil environment. FRONTIERS IN PLANT SCIENCE 2023; 14:1124139. [PMID: 37152182 PMCID: PMC10161901 DOI: 10.3389/fpls.2023.1124139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 02/13/2023] [Indexed: 05/09/2023]
Abstract
Introduction The competitive strategies of plants play a crucial role in their growth. Allelopathy is one of the weapons that plants use to improve their competitive advantage. Methods In order to explore the competitive strategy of a poisonous weed Elsholtzia densa Benth. (E. densa) on the Qinghai-Tibet Plateau (QTP), the effects of decomposing substances of E. densa on growth, root border cells (RBCs) characteristics of highland crop highland barley (Hordeum vulgare L.), and soil environment were determined. Results The decomposing allelopathic effect of E. densa on the germination and seedling growth of highland barley mainly occurred in the early stage of decomposing. The allelopathic effects were mainly on seed germination and root growth of highland barley. After treatment with its decomposing solution, the RBC's mucilage layer of highland barley thickened, and the RBC's activity decreased or even apoptosis compared with the control. However, only the above-ground part of the treatment group showed a significant difference. The effects of E. densa decomposed substances on the soil environment were evaluated from soil physicochemical properties and bacterial community. The results showed that soil bacteria varied greatly in the early stage of decomposion under different concentrations of E. densa. In addition, E. densa decomposing substances increased the soil nutrient content, extracellular enzyme activities, and bacterial community diversity. In the process of decomposition, the bacterial community structure changed constantly, but Actinobacteriota was always the dominant phylum. Discussion These results indicated that E. densa might adopt the following two strategies to help it gain an advantage in the competition: 1. Release allelochemicals that interfere with the defense function of surrounding plants and directly inhibit the growth and development of surrounding plants. 2. By changing the physical and chemical properties of soil and extracellular enzyme activity, residual plant decomposition can stimulate soil microbial activity, improve soil nutrition status, and create a more suitable soil environment for growth.
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Wang S, Jiao C, Zhao D, Zeng J, Xing P, Liu Y, Wu QL. Disentangling the assembly mechanisms of bacterial communities in a transition zone between the alpine steppe and alpine meadow ecosystems on the Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 847:157446. [PMID: 35863578 DOI: 10.1016/j.scitotenv.2022.157446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 07/13/2022] [Accepted: 07/13/2022] [Indexed: 06/15/2023]
Abstract
Alpine meadows and alpine steppes are two major grassland types distributed on the Tibetan Plateau. Due in large part to the differences in hydrothermal and nutrient conditions following the thawing of lakeshore permafrost, alpine meadows and alpine steppes which are characterized by disparate above- and below-ground biomass, could emerge together in the grassland transition zone between meadows and steppes of the Tibetan Plateau. Bacterial communities are essential components of alpine grassland ecosystems and respond rapidly to environmental changes. Despite their ecological significance, it remains poorly elucidated whether and how the assembly patterns of bacterial communities differed between alpine meadows and alpine steppes. Here, to disentangle the assembly mechanisms of bacterial communities from alpine meadows and alpine steppes, we collected samples from three diverse habitats (i.e., sediments, rhizosphere soils and bulk soils) in both alpine meadow and steppe ecosystems on the Tibetan Plateau. Our results indicated that in both meadows and steppes, rhizosphere bacterial communities exhibited higher alpha-diversity but lower beta-diversity compared to the bacterial communities in sediments and bulk soils. However, the close relationships of bacterial communities between different habitats weakened from meadows to steppes. Null model analysis indicated that the importance of environmental selection shaping bacterial community assemblages in all habitats decreased from meadows to steppes, whereas the role of dispersal limitation showed an opposite pattern. Moreover, pH was the primary driver of phylogenetic turnover of bacterial communities in the steppes across all habitats, whereas the dominant drivers of phylogenetic turnover of bacterial communities in meadows varied with habitat types. Overall, our findings provide novel insights into understanding the differences in microbial communities between meadows and steppes in the grassland transition zone on the Tibetan Plateau.
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Affiliation(s)
- Shuren Wang
- Joint International Research Laboratory of Global Change and Water Cycle, State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China; State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| | - Congcong Jiao
- Joint International Research Laboratory of Global Change and Water Cycle, State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China; State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| | - Dayong Zhao
- Joint International Research Laboratory of Global Change and Water Cycle, State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China
| | - Jin Zeng
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China; Sino-Danish Centre for Education and Research, University of Chinese Academy of Sciences, Beijing, China.
| | - Peng Xing
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| | - Yongqin Liu
- Center for the Pan-third Pole Environment, Lanzhou University, Lanzhou, China.; State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
| | - Qinglong L Wu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China; Sino-Danish Centre for Education and Research, University of Chinese Academy of Sciences, Beijing, China
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Determining the role of richness and evenness in alpine grassland productivity across climatic and edaphic gradients. Oecologia 2022; 200:491-502. [DOI: 10.1007/s00442-022-05279-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022]
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10
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Wang X, Sun L, Zhao N, Li W, Wei X, Niu B. Multifractal dimensions of soil particle size distribution reveal the erodibility and fertility of alpine grassland soils in the Northern Tibet Plateau. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 315:115145. [PMID: 35525043 DOI: 10.1016/j.jenvman.2022.115145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 04/20/2022] [Accepted: 04/21/2022] [Indexed: 06/14/2023]
Abstract
Climate change and human activities have seriously degraded alpine grassland, potentially affecting soil particle size distribution (PSD) and further influencing the nutrient levels and erodibility of soil. Predicting the fertility and erodibility of alpine soil using multifractal dimensions of soil PSD could be used to enhance the management and restoration of degraded alpine grasslands. In the present study, we evaluated three types of alpine grasslands: alpine meadow (AM), alpine steppe (AS), and alpine desert steppe (ADS). Fencing and grazing management measures were conducted at sites containing each grassland type. Then, we analyzed the PSDs, erodibility, and other properties of soil in the 0-20 cm soil layer. Multifractal characterization of soil PSD was calculated using the fractal scale theory. The findings showed that grassland type significantly impacted soil nutrients and the multifractal dimensions of soil PSDs, whereas management measures affected soil erodibility significantly. The proportion of finer particles decreased as follows: AM > AS > ADS. Compared to grazing, fencing enhanced clay content and reduced the proportion of coarser particles under all three grassland types. AM had higher organic carbon and nitrogen levels than AS and ADS. Multifractal dimensions were highest for AM, with ADS having higher erodibility than AM and AS. Multifractal dimensions (except for correlation dimension) also had significantly positive relationships with soil organic carbon and available nutrient content and soil erodibility, but had significantly negative correlations with soil pH, bulk density, and electrical conductivity. Thus, the multifractal dimensions of soil PSDs could be used to characterize the erodibility and fertility characteristics of soil in alpine regions, providing a reference for assessing vegetation restoration measures in the Northern Tibet Plateau.
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Affiliation(s)
- Xiangtao Wang
- Department of Animal Sciences, Xizang Agriculture and Animal Husbandry College, Linzhi, 860000, China; Lhasa National Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing, 100101, China; University of Chinese Academy of Sciences (UCAS), Beijing, 100049, China
| | - Lei Sun
- Department of Animal Sciences, Xizang Agriculture and Animal Husbandry College, Linzhi, 860000, China
| | - Ningning Zhao
- Department of Animal Sciences, Xizang Agriculture and Animal Husbandry College, Linzhi, 860000, China
| | - Wencheng Li
- Department of Animal Sciences, Xizang Agriculture and Animal Husbandry College, Linzhi, 860000, China
| | - Xuehong Wei
- Department of Animal Sciences, Xizang Agriculture and Animal Husbandry College, Linzhi, 860000, China.
| | - Ben Niu
- Lhasa National Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing, 100101, China; University of Chinese Academy of Sciences (UCAS), Beijing, 100049, China.
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Song S, Xiong K, Chi Y, He C, Fang J, He S. Effect of Cultivated Pastures on Soil Bacterial Communities in the Karst Rocky Desertification Area. Front Microbiol 2022; 13:922989. [PMID: 35966668 PMCID: PMC9368201 DOI: 10.3389/fmicb.2022.922989] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 06/21/2022] [Indexed: 11/13/2022] Open
Abstract
Soil bacteria play an important role in regulating the process of vegetation restoration in karst ecosystems. However, the effects of vegetation restoration for different cultivated pastures on soil bacterial communities in the karst rocky desertification regions remain unclear. Therefore, we hypothesized that mixed pasture is the most effective for soil bacterial communities among different vegetation restorations. In this study, we systematically studied the soil properties and soil bacterial communities in four vegetation restoration modes [i.e., Dactylis glomerata pasture (DG), Lolium perenne pasture (LP), Lolium perenne + Trifolium repens mixed pasture (LT), and natural grassland (NG)] by using 16S rDNA Illumina sequencing, combined with six soil indicators and data models. We found that the vegetation restoration of cultivated pastures can improve the soil nutrient content compared with the natural grassland, especially LT treatment. LT treatment significantly increased the MBC content and Shannon index. The vegetation restoration of cultivated pastures significantly increased the relative abundance of Proteobacteria, but LT treatment significantly decreased the relative abundance of Acidobacteria. Soil pH and MBC significantly correlated with the alpha diversity of soil bacterial. Soil pH and SOC were the main factors that can affect the soil bacterial community. FAPROTAX analysis showed LT treatment significantly decreased the relative abundance of aerobic chemoheterotrophs. The results showed that the bacterial communities were highly beneficial to soil restoration in the LT treatment, and it confirmed our hypothesis. This finding provides a scientific reference for the restoration of degraded ecosystems in karst rocky desertification areas.
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Affiliation(s)
- Shuzhen Song
- School of Karst Science, Guizhou Normal University, Guiyang, China
- State Engineering Technology Institute for Karst Desertification Control, Guiyang, China
| | - Kangning Xiong
- School of Karst Science, Guizhou Normal University, Guiyang, China
- State Engineering Technology Institute for Karst Desertification Control, Guiyang, China
| | - Yongkuan Chi
- School of Karst Science, Guizhou Normal University, Guiyang, China
- State Engineering Technology Institute for Karst Desertification Control, Guiyang, China
| | - Cheng He
- School of Karst Science, Guizhou Normal University, Guiyang, China
| | - Jinzhong Fang
- School of Karst Science, Guizhou Normal University, Guiyang, China
| | - Shuyu He
- School of Karst Science, Guizhou Normal University, Guiyang, China
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Li H, Qiu Y, Yao T, Han D, Gao Y, Zhang J, Ma Y, Zhang H, Yang X. Nutrients available in the soil regulate the changes of soil microbial community alongside degradation of alpine meadows in the northeast of the Qinghai-Tibet Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 792:148363. [PMID: 34465051 DOI: 10.1016/j.scitotenv.2021.148363] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 06/04/2021] [Accepted: 06/06/2021] [Indexed: 06/13/2023]
Abstract
The alpine meadow in the Qinghai-Tibet Plateau has been seriously degraded due to human activities and climate change in recent decades. Understanding the changes of the soil microbial community in response to the degradation process helps reveal the mechanism underlying the degradation process of alpine meadows. We surveyed and analyzed changes of the vegetation, soil physicochemical properties, and soil microbial community in three degradation levels, namely, non-degradation (ND), moderate degradation (MD), and severe degradation (SD), of the alpine meadows in the northeastern Qinghai-Tibet Plateau. We found that as the level of degradation increased, plant cover, plant density (PD), above-ground biomass (AGB), plant Shannon-Wiener index (PS), soil water content (SWC), soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), and available potassium (AK) decreased significantly, while the soil pH increased from 7.20 to 8.57. Alpine meadow degradation significantly changed the composition of soil bacterial and fungal communities but had no significant impact on the diversity of the microbial communities. Functional predictions indicated that meadow degradation increased the relative abundances of aerobic_chemoheterotrophy, undefined_saprotroph, and plant_pathogen, likely increasing the risk of plant diseases. Redundancy analysis revealed that in ND, the soil microbial community was mainly regulated by PS, PH, PD, SWC, and soil pH. In MD, the soil microbial community was regulated by the soil's available nutrients and SOC. In SD, the soil microbial community was not only regulated by the soil's available nutrients but also influenced by plant characteristics. These results indicate that during alpine meadow degradation, while the changes in the plants and soil environmental factors both affect the composition of the soil microbial community, the influence of soil factors is greater. The soil's available nutrients are the main driving factors regulating the change in the soil microbial community's composition alongside degradation levels.
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Affiliation(s)
- Haiyun Li
- Collaborative Innovation Center for Western Ecological Safety, Lanzhou University, Lanzhou 730000, China.
| | - Yizhi Qiu
- State Key Laboratory of Grassland Agro-ecosystems, School of Life Science, Lanzhou University, Lanzhou 730000, China
| | - Tuo Yao
- College of Grassland Science, Key Laboratory of Grassland Ecosystem of the Ministry of Education, Gansu Agricultural University, Lanzhou 730070, China
| | - Dongrong Han
- College of Grassland Science, Key Laboratory of Grassland Ecosystem of the Ministry of Education, Gansu Agricultural University, Lanzhou 730070, China
| | - Yamin Gao
- College of Grassland Science, Key Laboratory of Grassland Ecosystem of the Ministry of Education, Gansu Agricultural University, Lanzhou 730070, China
| | - Jiangui Zhang
- College of Grassland Science, Key Laboratory of Grassland Ecosystem of the Ministry of Education, Gansu Agricultural University, Lanzhou 730070, China
| | - Yachun Ma
- College of Grassland Science, Key Laboratory of Grassland Ecosystem of the Ministry of Education, Gansu Agricultural University, Lanzhou 730070, China
| | - Huirong Zhang
- College of Grassland Science, Key Laboratory of Grassland Ecosystem of the Ministry of Education, Gansu Agricultural University, Lanzhou 730070, China
| | - Xiaolei Yang
- College of Grassland Science, Key Laboratory of Grassland Ecosystem of the Ministry of Education, Gansu Agricultural University, Lanzhou 730070, China
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13
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Zhou T, Sun J, Zong N, Hou G, Shi P. Community species diversity mediates the trade-off between aboveground and belowground biomass for grasses and forbs in degraded alpine meadow, Tibetan Plateau. Ecol Evol 2021; 11:13259-13267. [PMID: 34646467 PMCID: PMC8495812 DOI: 10.1002/ece3.8048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 08/03/2021] [Accepted: 08/06/2021] [Indexed: 11/11/2022] Open
Abstract
Although many empirical experiments have shown that increasing degradation results in lower aboveground biomass (AGB), our knowledge of the magnitude of belowground biomass (BGB) for individual plants is a prerequisite for accurately revealing the biomass trade-off in degraded grasslands. Here, by linking the AGB and BGB of individual plants, species in the community, and soil properties, we explored the biomass partitioning patterns in different plant functional groups (grasses of Stipa capillacea and forbs of Anaphalis xylorhiza). Our results indicated that 81% and 60% of the biomass trade-off variations could be explained by environmental factors affecting grasses and forbs, respectively. The change in community species diversity dominated the biomass trade-off via either direct or indirect effects on soil properties and biomass. However, the community species diversity imparted divergent effects on the biomass trade-off for grasses (scored at -0.72) and forbs (scored at 0.59). Our findings suggest that plant communities have evolved two contrasting strategies of biomass allocation patterns in degraded grasslands. These are the "conservative" strategy in grasses, in which plants with larger BGB trade-off depends on gigantic roots for soil resources, and the "opportunistic" strategy in forbs, in which plants can adapt to degraded lands using high variation and optimal biomass allocation.
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Affiliation(s)
- Tiancai Zhou
- Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China
- College of Resources and Environment University of Chinese Academy of Sciences Beijing China
| | - Jian Sun
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE) Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China
| | - Ning Zong
- Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China
| | - Ge Hou
- Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China
- College of Resources and Environment University of Chinese Academy of Sciences Beijing China
| | - Peili Shi
- Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China
- College of Resources and Environment University of Chinese Academy of Sciences Beijing China
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Spatial and Temporal Differences in Alpine Meadow, Alpine Steppe and All Vegetation of the Qinghai-Tibetan Plateau and Their Responses to Climate Change. REMOTE SENSING 2021. [DOI: 10.3390/rs13040669] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Alpine meadow and alpine steppe are the two most widely distributed nonzonal vegetation types in the Qinghai-Tibet Plateau. In the context of global climate change, the differences in spatial-temporal variation trends and their responses to climate change are discussed. It is of great significance to reveal the response of the Qinghai-Tibet Plateau to global climate change and the construction of ecological security barriers. This study takes alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau as the research objects. The normalized difference vegetation index (NDVI) data and meteorological data were used as the data sources between 2000 and 2018. By using the mean value method, threshold method, trend analysis method and correlation analysis method, the spatial and temporal variation trends in the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau were compared and analyzed, and their differences in the responses to climate change were discussed. The results showed the following: (1) The growing season length of alpine meadow was 145~289 d, while that of alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau was 161~273 d, and their growing season lengths were significantly shorter than that of alpine meadow. (2) The annual variation trends of the growing season NDVI for the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau increased obviously, but their fluctuation range and change rate were significantly different. (3) The overall vegetation improvement in the Qinghai-Tibet Plateau was primarily dominated by alpine steppe and alpine meadow, while the degradation was primarily dominated by alpine meadow. (4) The responses between the growing season NDVI and climatic factors in the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau had great spatial heterogeneity in the Qinghai-Tibet Plateau. These findings provide evidence towards understanding the characteristics of the different vegetation types in the Qinghai-Tibet Plateau and their spatial differences in response to climate change.
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