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Yang H, Cheng L, Che L, Su Y, Li Y. Nutrients addition decreases soil fungal diversity and alters fungal guilds and co-occurrence networks in a semi-arid grassland in northern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:172100. [PMID: 38556007 DOI: 10.1016/j.scitotenv.2024.172100] [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: 12/28/2023] [Revised: 03/13/2024] [Accepted: 03/28/2024] [Indexed: 04/02/2024]
Abstract
Anthropogenic eutrophication is known to impair the diversity and stability of aboveground community, but its effects on the diversity, composition and stability of belowground ecosystems are not yet fully understood. In this study, we conducted a 9-year nitrogen (N) and phosphorus (P) addition experiment in a semi-arid grassland of Northern China to elucidate the impacts of nutrients addition on soil fungal diversity, functional guilds, and co-occurrence networks. The results showed that N addition significantly decreased soil fungal diversity and altered fungal community composition, whereas P addition had no impact on them. The relative abundance of arbuscular mycorrhizal fungi and leaf_saprotroph were reduced by N and P addition, but P addition enhanced the abundance of saprotrophic fungi. Co-occurrence network analysis revealed that N addition destabilized fungal network complexity and stability, while P addition slightly increased the network complexity. Additionally, the network analysis of N × P interaction revealed that P addition mitigated negative effects of N addition on network complexity and stability. Structural equation modeling (SEM) results suggested that nutrients addition directly or indirectly influenced the fungal community structure through the loss of plant richness and the increase of perennial grass biomass. These findings indicate that in comparison to P addition, N addition exhibits a pronounced negative effect on soil fungal communities. Our findings also suggest that changes in plant functional groups under nutrients deposition are pivotal in shaping soil fungal community structure in semi-arid grassland and highlight the need for a better understanding of the belowground ecosystem dynamics.
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Affiliation(s)
- Hongling Yang
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Tongliao 028300, China
| | - Li Cheng
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Tongliao 028300, China
| | - Limuge Che
- Graduate School of Dairy Science, Rakuno Gakuen University, Hokkaido, 069-8501, Japan
| | - YongZhong Su
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
| | - Yulin Li
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Tongliao 028300, China.
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Ye H, Tu N, Wu Z, He S, Zhao Y, Yue M, Hong M. Identification of bacteria and fungi responsible for litter decomposition in desert steppes via combined DNA stable isotope probing. Front Microbiol 2024; 15:1353629. [PMID: 38525080 PMCID: PMC10957780 DOI: 10.3389/fmicb.2024.1353629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 02/28/2024] [Indexed: 03/26/2024] Open
Abstract
Introduction Soil microorganisms play crucial roles in determining the fate of litter in desert steppes because their activities constitute a major component of the global carbon (C) cycle. Human activities lead to increased ecosystem nitrogen (N) deposition, which has unpredictable impacts on soil microorganism diversity and functions. Nowadays, it is necessary to further study the succession of these microorganisms in the process of litter decomposition in desert steppe, and explore the effect of N deposition on this process. This issue is particularly important to resolve because it contributes to the broader understanding of nutrient cycling processes in desert steppes. Methods In this study, DNA stable isotope probing (DNA-SIP) was used to study changes in soil bacterial and fungal community composition and function during 8 weeks of culture of 13C-labeled litter in desert steppes. Results The results were as follows: (1) Actinomycetota, Pseudomonadota, and Ascomycota are the main microorganisms involved in litter decomposition in desert steppes; (2) N deposition (50 kg ha-1 year-1) significantly increased the relative abundance of some microorganisms involved in the decomposition process; and (3) N deposition likely promotes litter decomposition in desert steppes by increasing the abundances of N cycles bacteria (usually carrying GH family functional genes). Discussion These findings contribute to a deeper understanding of the C assimilation mechanisms associated with litter residue production, emphasizing the importance of extensive C utilization.
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Affiliation(s)
- He Ye
- Key Laboratory of Soil Quality and Nutrient Resources, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Agricultural Ecological Security and Green Development, Universities of Inner Mongolia Autonomous Region, Hohhot, China
| | - Nare Tu
- Key Laboratory of Soil Quality and Nutrient Resources, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Agricultural Ecological Security and Green Development, Universities of Inner Mongolia Autonomous Region, Hohhot, China
| | - Zhendan Wu
- Key Laboratory of Soil Quality and Nutrient Resources, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Agricultural Ecological Security and Green Development, Universities of Inner Mongolia Autonomous Region, Hohhot, China
| | - Shilong He
- Key Laboratory of Soil Quality and Nutrient Resources, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Agricultural Ecological Security and Green Development, Universities of Inner Mongolia Autonomous Region, Hohhot, China
| | - Yu Zhao
- Key Laboratory of Soil Quality and Nutrient Resources, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Agricultural Ecological Security and Green Development, Universities of Inner Mongolia Autonomous Region, Hohhot, China
| | - Mei Yue
- Key Laboratory of Soil Quality and Nutrient Resources, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Agricultural Ecological Security and Green Development, Universities of Inner Mongolia Autonomous Region, Hohhot, China
| | - Mei Hong
- Key Laboratory of Soil Quality and Nutrient Resources, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Agricultural Ecological Security and Green Development, Universities of Inner Mongolia Autonomous Region, Hohhot, China
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Zhang Z, Tang G, Chai X, Liu B, Gao X, Zeng F, Wang Y, Zhang B. Different Responses of Soil Bacterial and Fungal Communities in Three Typical Vegetations following Nitrogen Deposition in an Arid Desert. Microorganisms 2023; 11:2471. [PMID: 37894130 PMCID: PMC10609353 DOI: 10.3390/microorganisms11102471] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/22/2023] [Accepted: 09/29/2023] [Indexed: 10/29/2023] Open
Abstract
The effects of increased nitrogen (N) deposition on desert ecosystems have been extensively studied from a plant community perspective. However, the response of soil microbial communities, which play a crucial role in nutrient cycling, to N inputs and plant community types remains poorly understood. In this study, we conducted a two-year N-addition experiment with five gradients (0, 10, 30, 60, and 120 kg N ha-1 year-1) to evaluate the effect of increased N deposition on soil bacterial and fungal communities in three plant community types, namely, Alhagi sparsifolia Shap., Karelinia caspia (Pall.) Less. monocultures and their mixed community in a desert steppe located on the southern edge of the Taklimakan Desert, Northwest China. Our results indicate that N deposition and plant community types exerted an independent and significant influence on the soil microbial community. Bacterial α-diversity and community dissimilarity showed a unimodal pattern with peaks at 30 and 60 kg N ha-1 year-1, respectively. By contrast, fungal α-diversity and community dissimilarity did not vary significantly with increased N inputs. Furthermore, plant community type significantly altered microbial community dissimilarity. The Mantel test and redundancy analysis indicated that soil pH and total and inorganic N (NH4+ and NO3-) levels were the most critical factors regulating soil microbial communities. Similar to the patterns observed in taxonomic composition, fungi exhibit stronger resistance to N addition compared to bacteria in terms of their functionality. Overall, our findings suggest that the response of soil microbial communities to N deposition is domain-specific and independent of desert plant community diversity, and the bacterial community has a critical threshold under N enrichment in arid deserts.
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Affiliation(s)
- Zhihao Zhang
- Xinjiang Key Laboratory of Desert Plant Roots Ecology and Vegetation Restoration, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; (Z.Z.)
- State Key Laboratory of Desert and Oasis Ecology, Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Cele National Station of Observation and Research for Desert-Grassland Ecosystems, Cele 848300, China
| | - Gangliang Tang
- Xinjiang Key Laboratory of Desert Plant Roots Ecology and Vegetation Restoration, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; (Z.Z.)
- State Key Laboratory of Desert and Oasis Ecology, Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Cele National Station of Observation and Research for Desert-Grassland Ecosystems, Cele 848300, China
| | - Xutian Chai
- Xinjiang Key Laboratory of Desert Plant Roots Ecology and Vegetation Restoration, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; (Z.Z.)
- State Key Laboratory of Desert and Oasis Ecology, Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Cele National Station of Observation and Research for Desert-Grassland Ecosystems, Cele 848300, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bo Liu
- School of Resources and Environment, Linyi University, Linyi 276000, China
| | - Xiaopeng Gao
- Department of Soil Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Fanjiang Zeng
- Xinjiang Key Laboratory of Desert Plant Roots Ecology and Vegetation Restoration, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; (Z.Z.)
- State Key Laboratory of Desert and Oasis Ecology, Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Cele National Station of Observation and Research for Desert-Grassland Ecosystems, Cele 848300, China
| | - Yun Wang
- Life Science and Technology School, Linnan Normal University, Zhanjiang 524048, China
| | - Bo Zhang
- Xinjiang Key Laboratory of Desert Plant Roots Ecology and Vegetation Restoration, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; (Z.Z.)
- Cele National Station of Observation and Research for Desert-Grassland Ecosystems, Cele 848300, China
- National Engineering Technology Research Center for Desert-Oasis Ecological Construction, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
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Fang Z, Yu H, Li C, Wang B, Jiao F, Huang J. Long-term phosphorus addition alters plant community composition but not ecosystem stability of a nitrogen-enriched desert steppe. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 879:163033. [PMID: 36966843 DOI: 10.1016/j.scitotenv.2023.163033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 03/03/2023] [Accepted: 03/20/2023] [Indexed: 05/17/2023]
Abstract
Under ongoing global change, whether grassland ecosystems can maintain their functions and services depends largely on their stability. However, how ecosystem stability responds to increasing phosphorus (P) inputs under nitrogen (N) loading remains unclear. We conducted a 7-year field experiment to examine the influence of elevated P inputs (ranging from 0 to 16 g P m-2 yr-1) on the temporal stability of aboveground net primary productivity (ANPP) under N addition of 5 g N·m-2·yr-1 in a desert steppe. We found that under N loading, P addition altered plant community composition but did not significantly affect ecosystem stability. Specifically, with the increase in the P addition rate, declines in the relative ANPP of legume could be compensated for by an increase in the relative ANPP of grass and forb species, yet community ANPP and diversity remained unchanged. Notably, the stability and asynchrony of dominant species tended to decrease with increasing P addition, and a significant decrease in legume stability was observed at high P rates (>8 g P m-2 yr-1). Moreover, P addition indirectly affected ecosystem stability by multiple pathways (e.g., species diversity, species asynchrony, dominant species asynchrony, and dominant species stability), as revealed by structural equation modeling results. Our results suggest that multiple mechanisms work concurrently in stabilizing the ecosystem stability of desert steppes and that increasing P inputs may not alter desert steppe ecosystem stability under future N-enriched scenarios. Our results will help improve the accuracy of vegetation dynamics assessments in arid ecosystems under future global change.
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Affiliation(s)
- Zhao Fang
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in northwestern China, Yinchuan 750021, China; Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in northwestern China of Ministry of Education, Yinchuan 750021, China; School of Ecology and Environment, Ningxia University, Yinchuan 750021, China; Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Hailong Yu
- School of Geography and Planning, Ningxia University, Yinchuan 750021, China
| | - Chunhuan Li
- School of Geography and Planning, Ningxia University, Yinchuan 750021, China
| | - Bin Wang
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Fuyang 311400, China
| | - Feng Jiao
- Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Juying Huang
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in northwestern China, Yinchuan 750021, China; Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in northwestern China of Ministry of Education, Yinchuan 750021, China; School of Ecology and Environment, Ningxia University, Yinchuan 750021, China.
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Song B, Li Y, Yang L, Shi H, Li L, Bai W, Zhao Y. Soil Acidification Under Long-Term N Addition Decreases the Diversity of Soil Bacteria and Fungi and Changes Their Community Composition in a Semiarid Grassland. MICROBIAL ECOLOGY 2023; 85:221-231. [PMID: 35043220 DOI: 10.1007/s00248-021-01954-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 12/21/2021] [Indexed: 06/14/2023]
Abstract
Soil microorganisms play key roles in terrestrial biogeochemical cycles and ecosystem functions. However, few studies address how long-term nitrogen (N) addition gradients impact soil bacterial and fungal diversity and community composition simultaneously. Here, we investigated soil bacterial and fungal diversity and community composition based on a long-term (17 years) N addition gradient experiment (six levels: 0, 2, 4, 8, 16, 32 gN m-2 year-1) in temperate grassland, using the high-throughput Illumina MiSeq sequencing. Results showed that both soil bacterial and fungal alpha diversity responded nonlinearly to the N input gradient and reduced drastically when the N addition rate reached 32 g N m-2 year-1. The relative abundance of soil bacterial phyla Proteobacteria increased and Acidobacteria decreased significantly with increasing N level. In addition, the relative abundance of bacterial functional groups associated with aerobic ammonia oxidation, aerobic nitrite oxidation, nitrification, respiration of sulfate and sulfur compounds, and chitinolysis significantly decreased under the highest N addition treatment. For soil fungi, the relative abundance of Ascomycota increased linearly along the N enrichment gradient. These results suggest that changes in soil microbial community composition under elevated N do not always support the copiotrophic-oligotrophic hypothesis, and some certain functional bacteria would not simply be controlled by soil nutrients. Further analysis illustrated that reduced soil pH under N addition was the main factor driving variations in soil microbial diversity and community structure in this grassland. Our findings highlight the consistently nonlinear responses of soil bacterial and fungal diversity to increasing N input and the significant effects of soil acidification on soil microbial communities, which can be helpful for the prediction of underground ecosystem processes in light of future rising N deposition.
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Affiliation(s)
- Bing Song
- School of Resources and Environmental Engineering, Ludong University, Yantai, 264025, China.
| | - Yong Li
- Beijing Key Laboratory of Wetland Services and Restoration, Institute of Wetland Research, Chinese Academy of Forestry, Beijing, 100091, China
| | - Liuyi Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Huiqiu Shi
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Linghao Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Wenming Bai
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Ying Zhao
- School of Resources and Environmental Engineering, Ludong University, Yantai, 264025, China
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Zhang X, Song X, Wang T, Huang L, Ma H, Wang M, Tan D. The responses to long-term nitrogen addition of soil bacterial, fungal, and archaeal communities in a desert ecosystem. Front Microbiol 2022; 13:1015588. [PMID: 36312972 PMCID: PMC9606763 DOI: 10.3389/fmicb.2022.1015588] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 09/26/2022] [Indexed: 10/29/2023] Open
Abstract
Nitrogen (N) deposition is a worldwide issue caused by human activity. Long-term deposition of N strongly influences plant productivity and community composition. However, it is still unclear how the microbial community responds to long-term N addition in a desert ecosystem. Therefore, a long-term experiment was conducted in the Gurbantonggut Desert in northwestern China in 2015. Four N addition rates, 0 (CK), 5 (N1), 20 (N2), and 80 (N3) kg N ha-1 yr.-1, were tested and the soil was sampled after 6 years of N addition. High-throughput sequencing (HTS) was used to analyze the soil microbial composition. The HTS results showed that N addition had no significant effect on the bacterial α-diversity and β-diversity (p > 0.05) but significantly reduced the archaeal β-diversity (p < 0.05). The fungal Chao1 and ACE indexes in the N2 treatment increased by 24.10 and 26.07%, respectively. In addition, N addition affected the bacterial and fungal community structures. For example, compared to CK, the relative abundance of Actinobacteria increased by 17.80%, and the relative abundance of Bacteroidetes was reduced by 44.46% under N3 treatment. Additionally, N addition also changed the bacterial and fungal community functions. The N3 treatment showed increased relative abundance of nitrate-reducing bacteria (27.06% higher than CK). The relative abundance of symbiotrophic fungi was increased in the N1 treatment (253.11% higher than CK). SOC and NH4 +-N could explain 62% of the changes in the fungal community function. N addition can directly affect the bacterial community function or indirectly through NO3 --N. These results suggest that different microbial groups may have various responses to N addition. Compared with bacteria and fungi, the effect of N addition was less on the archaeal community. Meanwhile, N-mediated changes of the soil properties play an essential role in changes in the microbial community. The results in the present study provided a reliable basis for an understanding of how the microbial community in a desert ecosystem adapts to long-term N deposition.
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Affiliation(s)
- Xuan Zhang
- College of Life Sciences, Xinjiang Agricultural University, Ürümqi, China
| | - Xin Song
- State Key Laboratory of Grassland Agro-Ecosystems, Institute of Arid Agroecology, College of Ecology, Lanzhou University, Lanzhou, China
| | - Taotao Wang
- College of Life Sciences, Xinjiang Agricultural University, Ürümqi, China
| | - Lei Huang
- College of Life Sciences, Xinjiang Agricultural University, Ürümqi, China
| | - Haiyang Ma
- College of Life Sciences, Xinjiang Agricultural University, Ürümqi, China
| | - Mao Wang
- College of Life Sciences, Xinjiang Agricultural University, Ürümqi, China
| | - Dunyan Tan
- College of Life Sciences, Xinjiang Agricultural University, Ürümqi, China
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Rong X, Zhou X, Li X, Yao M, Lu Y, Xu P, Yin B, Li Y, Aanderud ZT, Zhang Y. Biocrust diazotrophs and bacteria rather than fungi are sensitive to chronic low N deposition. Environ Microbiol 2022; 24:5450-5466. [PMID: 35844197 DOI: 10.1111/1462-2920.16095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 06/03/2022] [Indexed: 11/03/2022]
Abstract
Anthropogenic long-term nitrogen (N) deposition may dramatically impact biocrusts due to the overarching N limitation of soil biota in deserts. Even low levels of N may reach a critical loading threshold altering biocrust constituents and function. To identify the impact of chronic and continuous low levels of N deposition on biocrusts, we created a realistic gradient mirroring anthropogenic N addition rate (2:1 NH4 + : NO3 - rates: 0.3, 0.5, 1.0, 1.5, 3 g N m-2 yr-1 ) and measured the response of bacteria and fungi within cyanobacterial-dominated biocrusts over 8 years in a temperate desert, the Gurbantunggut Desert, China. We found that once N deposition reached 1.5 g N m-2 yr-1 biocrust bacterial communities, including diazotrophs, were altered while no such tipping point existed for fungi. Above the threshold, bacterial richness was enhanced, the relative abundance of Chloroflexi, FBP and Gemmatimonadetes was elevated, and diazotrophs shifted from being dominated by Nostocaceae and Scytonemataceae (Cyanobacteria) to free-living Bradyrhizobiaceae (Alphaproteobacteria). Alternatively, the relative recovery of a few fungal species within the Lecanorales, Pleosporales and Verrucariales became either enriched or diminished due to N deposition. The chronic addition of N resulted in a dense and interconnected bacterial co-occurrence network that accentuated a functional shift from networks dominated by phototrophic species within the Nostocaceae, Xenococcaceae, Phormidiaceae and Scytonemataceae (Cyanobacteria) to ammonia-oxidizing species within the Nitrosomonadaceae (Betaproteobacteria) and nitrifying bacteria [i.e. Nitrospiraceae (Nitrospirae)]. Based on structural equation models, the effects of N additions on biocrust constituents were imposed through indirect effects on pH, soil electrical conductivity and ammonium concentrations. In summary, biocrust constituents are generally insensitive to chronic low levels of N depositions until rates reach above 1.5 g N m-2 yr-1 with diazotrophs being the most sensitive biocrust constituents followed by bacteria and finally fungi. Ultimately once the threshold is reached N deposition favours biocrust constituents utilizing inorganic N and other C sources over relying on phototrophic and/or N-fixing cyanobacteria for C and N.
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Affiliation(s)
- Xiaoying Rong
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
| | - Xiaobing Zhou
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
| | - Xiangzhen Li
- Key Laboratory of Environmental and Applied Microbiology, Chinese Academy of Sciences, and Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Minjie Yao
- College of Resources and Environment, Fujian Agriculture and Forest University, Fuzhou, China
| | - Yongxing Lu
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.,University of the Chinese Academy of Sciences, Beijing, China
| | - Peng Xu
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.,University of the Chinese Academy of Sciences, Beijing, China
| | - Benfeng Yin
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
| | - Yonggang Li
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
| | - Zachary T Aanderud
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, USA
| | - Yuanming Zhang
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
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