Current Issue
  • Volume 16 Issue 6
    The diagram shows how managing biodiversity and trophic interactions across the food web can enhance ecosystem functions and services in agricultural systems, leading to the ecological intensification of agriculture. The Images used to create the diagram are from Integration and Application Network (ian.umces.edu/media-library). See Buzhdygan & Petermann in this issue.
      
    Review
    Zi-Jun Ji, Lu-Feng Zhao, Tao-Jie Zhang, Ran-Xin Dai, Jian-Jun Tang, Liang-Liang Hu, Xin Chen
    2023, 16 (6): rtad014.
    Abstract ( 123 )   PDF(pc) (370KB) ( 154 )   Save
    Species coculture can increase agro-biodiversity and therefore constitutes an ecological intensification measure for agriculture. Rice-aquatic animal coculture, one type of species coculture, has been practiced and researched widely. Here, we review recent studies and present results of a quantitative analysis of literature on rice-aquatic animal coculture systems. We address three questions: (i) can rice yield and soil fertility be maintained or increased with less chemical input through rice-aquatic animal coculture? (ii) how do aquatic animals benefit the paddy ecosystem? (iii) how can coculture be implemented for ecological intensification? Meta-analysis based on published papers showed that rice-aquatic animal cocultures increased rice yield, soil organic carbon and total nitrogen and decreased insect pests and weeds compared with rice monocultures. Studies also showed that rice-aquatic animal cocultures reduced pesticide and fertilizer application compared with rice monocultures. Rice plants provide a beneficial environment for aquatic animals, leading to high animal activities in the field. Aquatic animals, in turn, help remove rice pests and act as ecological engineers that affect soil conditions, which favor the growth of rice plants. Aquatic animals promote nutrient cycling and the complementary use of nutrients between rice and aquatic animals, which enhances nutrient-use efficiency in the coculture. To generate beneficial outcomes, how to develop compatible partnerships between rice and aquatic animals, and compatible culturing strategies for coculture systems are the key points. Investigating which traits of aquatic animals and rice varieties could best match to create productive and sustainable coculture systems could be one of the future focuses.
    Rob W. Brooker, Cathy Hawes, Pietro P. M. Iannetta, Alison J. Karley, Delphine Renard
    2023, 16 (6): rtad015.
    Abstract ( 111 )   PDF(pc) (650KB) ( 164 )   Save
    Ecological intensification (EI) is the enhancement of ecosystem services to complement or substitute for the role of anthropogenic inputs in maintaining or increasing yields. EI has potential to increase farming’s environmental sustainability, e.g. reducing environmentally harmful management activities while sustaining yields. EI is based upon ecological processes which in turn are influenced by biodiversity. We review how biodiversity, particularly vascular plant diversity, can regulate ecosystem processes relevant to EI at multiple spatial scales. At an individual plant genotype level, complementarity in functional traits has a direct impact on productivity. At in-field, population level, mixtures of crop types confer resilience to minimize the risk of pest and disease incidence and spread. Scaling up to the field level, a diversity of non-crop plants (i.e. weeds) provides resources necessary for in-field functional processes, both below ground (carbon inputs, decomposition) and above ground (resource continuity for pollinators and natural enemies). At the landscape scale, mosaics of semi-natural and managed vegetation provide buffers against extreme events through flood and drought risk mitigation, climate amelioration and pest population regulation. Overall this emphasizes the importance of heterogeneity across scales in maintaining ecosystem functions in farmland. Major research challenges highlighted by our review include the need: to better integrate plant functional diversity (from traits to habitat scales) into cropping system design; to quantify the (likely interactive) contribution of plant diversity for effective EI relative to other management options; and to optimize through targeted management the system function benefits of biodiversity for resilient, efficient and productive agroecosystems.
    Christian Schöb, Nadine Engbersen, Jesús López-Angulo, Anja Schmutz, Laura Stefan
    2023, 16 (6): rtad016.
    Abstract ( 59 )   PDF(pc) (724KB) ( 61 )   Save
    Inspired by grassland biodiversity experiments studying the impact of plant diversity on primary productivity, the Crop Diversity Experiment setup in 2018 aimed at testing whether these biodiversity benefits also hold for annual crop systems and whether crop mixtures also achieved transgressive overyielding, i.e. yield in mixture that was higher than the most productive monoculture. The first 3 years of the experiment demonstrated that crop mixtures do not only increase yield compared with an average monoculture but often also compared with the highest yielding monoculture. The crop diversity effects were stronger under more stressful environmental conditions and were often achieved in mixtures with legume crops. However, we observed transgressive overyielding also under favorable conditions and in mixtures without legumes. With our investigation of the underlying mechanisms of the yield benefits we found both direct complementarities between crop species and indirect effects via other organisms. The former included chemical, spatial and temporal complementarity in Nuptake, complementary root distribution leading to complementary water uptake, as well as spatial and temporal complementarity in light use. Among the indirect mechanisms we identified complementary suppression of weeds and more abundant plant growth-promoting microbes in crop mixtures, apart from complementarity in pest and disease suppression not yet studied in the Crop Diversity Experiment but demonstrated elsewhere. In consequence, the Crop Diversity Experiment supports not only the assumption that the ecological processes identified in biodiversity experiments also hold in crop systems, but that diversification of arable crop systems provides a valuable tool to sustainably produce food.
    Emanuel B. Kopp, Pascal A. Niklaus, Samuel E. Wuest
    2023, 16 (6): rtad017.
    Abstract ( 50 )   PDF(pc) (841KB) ( 83 )   Save
    Crop variety mixtures can provide many benefits, including pathogen suppression and increased yield and yield stability. However, these benefits do not necessarily occur in all mixtures, and the benefits of diversity may be compromised by disadvantages due to increased crop heterogeneity. In-field development of mixtures by assembling many combinations of crop genotypes without prior expectation about which genotypes need to be combined to produce well-performing mixtures results in prohibitively large designs. Therefore, effective tools are required to narrow down the number of promising variety mixtures, and to then identify in experiments which of these deliver the highest benefits. Here, we first review current knowledge about the mechanisms underlying effects in ecological diversity experiments and in current agricultural applications. We then discuss some of the principal difficulties arising in the application of this knowledge to develop good variety mixtures. We also discuss non-conventional approaches to solve some of these issues. In particular, we highlight the potential and limitations of trait-based methods to determine good variety mixing partners, and argue that nontraditional traits and trait-derived metrics may be needed for the trait-based approach to deliver its full potential. Specifically, we argue that good mixing partners can be identified using modern genetic and genomic approaches. Alternatively, good mixtures may be obtained by combining varieties that respond differently to environmental variation; such varieties could easily be identified in standard variety testing trials. Preliminary analyses show that niche differences underlying the different environmental responses can indicate functional complementarity and promote mixture yield and yield stability.
    Research Article
    Oksana Y. Buzhdygan, Jana S. Petermann
    2023, 16 (6): rtad019.
    Abstract ( 68 )   PDF(pc) (2683KB) ( 109 )   Save
    One central challenge for humanity is to mitigate and adapt to an ongoing climate and biodiversity crisis while providing resources to a growing human population. Ecological intensification (EI) aims to maximize crop productivity while minimizing impacts on the environment, especially by using biodiversity to improve ecosystem functions and services. Many EI measures are based on trophic interactions between organisms (e.g. pollination, biocontrol). Here, we investigate how research on multitrophic effects of biodiversity on ecosystem functioning could advance the application of EI measures in agriculture and forestry. We review previous studies and use qualitative analyses of the literature to test how important variables such as landuse parameters or habitat complexity affect multitrophic diversity, ecosystem functions and multitrophic biodiversity-ecosystem functioning relationships. We found that positive effects of biodiversity on ecosystem functions are prevalent in production systems, largely across ecosystem function dimensions, trophic levels, study methodologies and different ecosystem functions, however, with certain context dependencies. We also found strong impacts of land use and management on multitrophic biodiversity and ecosystem functions. We detected knowledge gaps in terms of data from underrepresented geographical areas, production systems, organism groups and functional diversity measurements. Additionally, we identified several aspects that require more attention in the future, such as trade-offs between multiple functions, temporal dynamics, effects of climate change, the spatial scale of the measures and their implementation. This information will be vital to ensure that agricultural and forest landscapes produce resources for humanity sustainably within the environmental limits of the planet.
    Perspective
    Qing Liu, Wenqiang Zhao
    2023, 16 (6): rtad021.
    Abstract ( 36 )   PDF(pc) (429KB) ( 33 )   Save
    Research Article
    Mustapha Ennajeh, Mitchell Coleman, Jaycie C. Fickle, Viridiana Castro, Robert Brandon Pratt, Anna L. Jacobsen
    2023, 16 (6): rtad022.
    Abstract ( 37 )   PDF(pc) (1753KB) ( 65 )   Save
    Two formerly broadly distributed woody Atriplex species now occur as fragmented populations across a range of microhabitats in the San Joaquin Valley Desert, southern California. We hypothesized that A. lentiformis and A. polycarpa exhibit inter- and intra-specific differences in their leaf and stem structural and functional traits corresponding with differences in soil salinity and aridity. Water potential, xylem structure and function and leaf traits were compared between three populations of A. lentiformis and four populations of A. polycarpa. The two species significantly differed in their xylem traits, with A. lentiformis displaying lower xylem density, wider mean and maximum vessel diameters and higher hydraulic conductivity (Ks). They also differed in their leaf traits, such that A. lentiformis had larger leaves with higher specific leaf area (SLA) than A. polycarpa. Significant intra-specific differences occurred among leaf traits (leaf area, SLA) in A. lentiformis populations. In contrast, populations varied in their stem xylem structural traits (mean vessel wall thickness, mean vessel diameter, maximum vessel length) among A. polycarpa populations. Many of these differences were associated with soil salinity in A. lentiformis, and with minimum seasonal water potential in A. polycarpa. Overall, both saltbush species showed high intra- and inter-specific trait variation. This could be a critical consideration in understanding the evolution of these native species and has important implications for their conservation and restoration.
    Editorial
    Bernhard Schmid, Christian Schöb
    2023, 16 (6): rtad018.
    Abstract ( 79 )   PDF(pc) (195KB) ( 113 )   Save
    Research Article
    Yan Zhang, Yanhong Tang
    2023, 16 (6): rtad023.
    Abstract ( 53 )   PDF(pc) (2169KB) ( 47 )   Save
    Although flower temperature plays an important role in plant reproduction, how it varies spatially on the flower surface is unclear, especially in alpine plants. To characterize spatial variation in flower surface temperature, we examined thermal images of flowers of 18 species along an altitudinal transect from 3200 to 4000 m on Lenglong Mountain on the north-eastern Qinghai-Tibetan Plateau. The surface temperature varied considerably within a flower or floral unit in all plants under sunlight, and was about 1 °C with a maximum of 11 °C higher in the center than at the edges. Solar radiation and flower shape significantly affected the temperature range and standard deviation and the ratio of flower center to edge temperature. The spatial variability of temperature increased with flower size. Flowers in the Asteraceae had higher surface temperatures, greater spatial variability of temperature, and consistently higher and more stable temperatures in the center than at the edge. The ratio of flower center to edge temperature increased with altitude in most species. Heat buildup at the flower center is likely to be widespread in alpine plants; further studies are needed to explore its ecological and evolutional roles.
    Yong-Peng Cha, Jie Zhang, Yin-Mei Ma, Zhao-Li Tong, Yun Wu, Lun Luo, Qing-Jun Li
    2023, 16 (6): rtad024.
    Abstract ( 96 )   PDF(pc) (875KB) ( 74 )   Save
    Spatiotemporal variations in plant-pollinator interactions drive floral evolution and shape the diversity of flowers in angiosperms. However, the potential role of plant-pollinator interactions in driving floral differentiation across flowering times within a population has not been documented. In this study, we aimed to quantify the variations in pollinator-mediated selection of floral traits across different flowering times of Primula sikkimensis (an entomophilous plant) in two natural populations. The results demonstrated that plants were shorter and produced fewer flowers with larger sizes in the early flowering time than in the late flowering time. In early flowering time, pollinator types were fewer and visitation frequency was lower than in late flowering time, resulting in lower female fitness. Pollinator-mediated selection of floral traits varied with flowering time, and more floral traits received pollinator-mediated selection during early flowering time. These results highlight that temporal variation in plant-pollinator interactions may have a potential role in driving floral diversification within the population.
    Renfei Chen, Cenxi Shi, Liang Zhang, Chengyi Tu, Jacob Weiner
    2023, 16 (6): rtad025.
    Abstract ( 47 )   PDF(pc) (1390KB) ( 27 )   Save
    According to the original optimal reproductive allocation theory, plants should shift from vegetative growth to reproductive allocation abruptly and completely. Some plants do this, and it is also considered a good strategy for crop plants to maximize yield, but most plants shift gradually. Modified versions of the theory predict such a gradual transition from growth to reproduction. We hypothesize that kin selection can also alter the predictions of optimal allocation theory. We investigated the theoretical implications of both positive and negative kin selection on the timing of plant reproductive development using mathematical models. Under reasonable assumptions of costs and benefits, plants under kin selection are more likely to shift from growth to reproduction in an abrupt way when the initial value of the ratio between reproductive and vegetative biomass is high. Supported by empirical observations, our theoretical predictions have important implications in linking life history and energy allocation as well as for improving yields in agriculture.
    Kittisack Phoutthavong, Masatoshi Katabuchi, Akihiro Nakamura, Xiao Cheng, Min Cao
    2023, 16 (6): rtad026.
    Abstract ( 66 )   PDF(pc) (817KB) ( 47 )   Save
    Plant species often show different taxonomic and functional characteristics between limestone forests (LFs) and non-limestone forests (NLFs) in tropical regions. Pteridophyte species are one of the major components in tropical rainforests; however, the morphological and physiological characteristics of pteridophytes occurring in LFs are poorly understood. We evaluated the differences in seven leaf functional traits between pteridophyte species in LFs and NLFs in southwest China. We measured leaf water content, morphological traits including leaf size, leaf thickness, stomatal length and stomatal density (SD), and physiological traits including stomatal conductance and photosynthetic rate from a total of 25 species. We found that pteridophytes had thicker and smaller leaves with lower SD and stomatal conductance in LFs compared with NLFs, probably reflecting their adaptations in water use strategies. These differences, however, became non-significant when phylogenetic relationships were taken into account, suggesting that phylogenetic conservatism shapes trait differences and ultimately species composition in LFs and NLFs. Some species that were commonly found in both LFs and NLFs exhibited intraspecific variation between forest types, with lower SD in LFs. Our findings suggest that only a handful of pteridophyte species can adapt to their water use strategies in both LFs and NLFs, and thus adaptative radiation is unlikely to occur.
    Zheng-Chao Yu, Xiao-Ting Zheng, Wei He, Wei Lin, Guan-Zhao Yan, Hui Zhu, Chang-Lian Peng
    2023, 16 (6): rtad027.
    Abstract ( 48 )   PDF(pc) (872KB) ( 26 )   Save
    Differences in plant leaf elemental contents due to seasonal climate change reflect potential plant growth strategies. However, the distribution patterns of elements mediated by seasonal climate change remain unclear. This limits assessment of plant growth status and prediction of plant growth dynamics under global climate change. We collected 41 subtropical evergreen broadleaf plant leaves (31 tree species and 10 shrub species) during the wet and dry seasons, and determined foliar contents of macro- and microelements by inductively coupled plasma mass spectrometer. Our results showed that 41 plant leaves had significantly greater macroelement contents and significantly lower microelement contents in wet season than dry season. The highest macroelement content was in tree layer plants in wet season, followed by tree layer plants in dry season and shrub layer plants in wet season, the lowest was in shrub layer plants in dry season. The highest microelement content was in tree and shrub layer plants in dry season, followed by shrub layer plants in wet season, the lowest was in tree layer plants in wet season. Our results show that macro- and microelement contents of plant leaves with different vertical structures are affected by seasonal climate change. The transition from wet to dry season was detrimental to tree layer plants growth, but had less impact on shrub layer plants growth. These findings provide valuable evidence for predicting how different vertically structured subtropical evergreen broadleaf plants can adapt to changes in wet and dry season environments and to future global climate change.
    Wei Wang, Xiaodan Sun, Wenhao Huang, Xiaoting Men, Shijie Yi, Fengrong Zheng, Zhaohui Zhang, Zongling Wang
    2023, 16 (6): rtad028.
    Abstract ( 46 )   PDF(pc) (1036KB) ( 50 )   Save
    High total P content but insufficient available P in soil is an obstacle that restricts the efficient utilization of P in saline-alkali soil regions. Although saline-alkali resistant P-solubilizing bacteria (PSB) solubilize insoluble P, few studies have focused on their application in plant growth. We isolated a PSB strain, identified as Bacillus sp. DYS211, from bird droppings in saline-alkali regions and determined its growth characteristics and resistance to salt and alkalis. To investigate the effect of PSB on the germination and growth of plant seeds, we performed a potting experiment using Suaeda salsa with PSB added. The PSB strain grew rapidly in the first 12 h, and the solubilized P content from PSB reached a maximum of 258.22 mg L-1 at 48 h. Saline-alkali tolerance and P-solubilizing ability tests showed that Bacillus sp. DYS211 preferred to dissolve inorganic P, was halophilic, and had a good P-solubilizing effect at 1%-8% salinity (available P > 150 mg L-1). It exhibited good P solubilization abilities when glucose and sucrose were used as C sources or when ammonium sulfate, ammonium nitrate or yeast extract powder were used as N sources. In the growth promotion test, PSB increased seed germination, particularly under high-salinity stress, with a growth promotion of 8.33%. The PSB also improved the growth of S. salsa, including plant height and biomass (up to three times) under both saline and alkaline conditions, and the stem diameter increased under high-salinity stress. This strain demonstrates potential for vegetation restoration in saline-alkali regions.
    Editorial
    Wen-Hao Zhang, Bernhard Schmid
    2023, 16 (6): rtad029.
    Abstract ( 22 )   PDF(pc) (254KB) ( 19 )   Save
    Research Article
    Huayue Nie, Chenrui Wang, Meirong Tian, Jixi Gao
    2023, 16 (6): rtad031.
    Abstract ( 22 )   PDF(pc) (1809KB) ( 11 )   Save
    Litter inputs have great impacts on the soil properties and ecosystem functioning in forests. Rapid litter decomposition leads to decreases in planted forest agricultural waste and enhances the nutrient cycle in forests. The breakdown of litter and the release of various components depend heavily on enzymes. However, the effects of exogenous enzyme preparations on litter decomposition have been hardly investigated. In this study, we examined how these enzymes affected the remaining rate of litter quality, nutrient content (C, N, K), and microbial community diversity. Taking Eriobotrya japonica litter as the research object, five exogenous enzymes (laccase, lignin peroxidase, leucine arylamidase, cellulase, and acid phosphatase) were applied to litter leaves. The mass remaining rate and main nutrient content of the litter were measured during the decomposition period. The microbial diversity attached to the surface of the litter was determined after decomposition at constant temperature and humidity for 189 days. Application of laccase and lignin peroxidase increased litter degradation by affecting microbial diversity, N and K contents. Addition of leucine arylamidase leaded to an increase in N content, and decreased the quality of the litter. The cellulose and lignin decomposition rate in litters was unaffected by the addition of cellulase, laccase, and lignin peroxidase. These results indicate that exogenous addition of enzymes may alter the nutrient content and microbial community, thus affecting litter decomposition. It is imperative to investigate the effects and mechanisms of exogenous enzymes on litter decomposition for regulating decomposition of agricultural waste litter.
    Qiang Sun, Hang-Yu Li, Kuan Li, Xiao-Qing Zhang, Ya-Bo Shi, Yan-Tao Wu, Xing Li, Zhi-Yong Li, Jing-Hui Zhang, Li-Xin Wang, Cun-Zhu Liang
    2023, 16 (6): rtad032.
    Abstract ( 23 )   PDF(pc) (2133KB) ( 16 )   Save
    Soil microorganisms, which include many rare taxa and a small number of abundant taxa, have different contributions to the ecosystem functions and services. High throughput sequencing technology was used to analyze the species composition of soil samples by DNA sequencing. Soil microorganisms were divided into abundant taxa and rare taxa to reveal their composition. Correlation analysis and random forest method were used to further analyze the influence of environmental factors on the community. Finally, the beta nearest taxon index (βNTI) based on the null model was used to elucidate the mechanisms underlying soil microbial community assembly. We found that, in desert soil, the community assembly of rare bacteria was almost entirely dominated by a homogeneous selection of deterministic processes. For comparison, stochastic processes had more pronounced effects on the abundant bacteria. However, both abundant and rare fungi exhibited similar patterns of community assembly, i.e. deterministic and stochastic processes jointly determined the assembly processes of fungal communities. We also observed that community assembly shifted from stochastic to deterministic processes with increasing mean annual precipitation (MAP) and mean annual temperature (MAT) for abundant bacteria. Conversely, for rare fungi, there was an inclination toward a shift from deterministic to stochastic processes with rising MAT. In conclusion, our findings provide compelling evidence that MAT and MAP regulate the community assembly process of abundant and rare microbial communities in desert soil. These findings establish a theoretical foundation for future investigations into the community structure and ecological functions of soil microorganisms.
    Lihua Zhang, Lizhi Jia, Liyuan He, David A. Lipson, Yihui Wang, Shunzhong Wang, Xiaofeng Xu
    2023, 16 (6): rtad035.
    Abstract ( 17 )   PDF(pc) (2253KB) ( 11 )   Save
    The theory of microbial stoichiometry can predict the proportional coupling of microbial assimilation of carbon (C), nitrogen (N), and phosphorus (P). The proportional coupling is quantified by the homeostasis value (H). Covariation of H values for C, N, and P indicates that microbial C, N, and P assimilation are coupled. Here, we used a global dataset to investigate the spatiotemporal dynamics of H values of microbial C, N, and P across biomes. We found that land use and management led to the decoupling of P from C and N metabolism over time and across space. Results from structural equation modeling revealed that edaphic factors dominate the microbial homeostasis of P, while soil elemental concentrations dominate the homeostasis of C and N. This result was further confirmed using the contrasting factors on microbial P vs. microbial C and N derived from a machine-learning algorithm. Overall, our study highlights the impacts of management on shifting microbial roles in nutrient cycling.
    Jiangshan Lai, Weijie Zhu, Dongfang Cui, Lingfeng Mao
    2023, 16 (6): rtad038.
    Abstract ( 101 )   PDF(pc) (506KB) ( 67 )   Save
    glmm.hp is an R package designed to evaluate the relative importance of collinear predictors within generalized linear mixed models (GLMMs). Since its initial release in January 2022, it has been rapidly gained recognition and popularity among ecologists. However, the previous glmm.hp package was limited to work GLMMs derived exclusively from the lme4 and nlme packages. The latest glmm.hp package has extended its functions. It has integrated results obtained from the glmmTMB package, thus enabling it to handle zero-inflated generalized linear mixed models (ZIGLMMs) effectively. Furthermore, it has introduced the new functionalities of commonality analysis and hierarchical partitioning for multiple linear regression models by considering both unadjusted R2 and adjusted R2
    Shuping Guan, Pengdong Chen, Xingle Qu, Xiaolan Wang, Shuopeng Wang, Haiying Li, Jiangping Fang, Yi Wang, Jiarui Chen, Wei Huang, Evan Siemann
    2023, 16 (6): rtad039.
    Abstract ( 49 )   PDF(pc) (1018KB) ( 30 )   Save
    Managing invasions in the context of globalization is a challenge in part because of the difficulty of inferring invader impacts from their invasiveness (i.e. ability to invade ecosystems). Specifically, the relationship between invasiveness and impact may be context-dependent and it has not been explored in such a unique ecosystem as the Tibetan Plateau. Here, we investigated 32 invasive plant species on the Tibetan Plateau in terms of their distribution, abundance, per capita effects on natives and traits across a large geographic transect to test the relationship between invasiveness and impacts on native communities. We decomposed the components (range, R; local abundance, A; per capita effect, E) that drive the impacts, and investigated the relative contributions of plant traits to these components. The results showed that there was no correlation between invasiveness (R × A) and impacts (R × A × E) of invasive species on the Tibetan Plateau. Specifically, plant invasiveness per se did not indicate a serious threat of harmful impact. In this ecosystem, R and A together drove invasiveness, while R alone drove impacts. Fruit type significantly influenced E, and species bearing berry fruits had the most negative per capita effects. However, plant traits did not drive invasiveness or impact through R, A or E. Our results suggest that the mismatch between components driving invasiveness vs. impact prevent the prediction of impacts of invasive species from their invasiveness. Therefore, management actions directed against invasive plants should prioritize broadly distributed species or those with demonstrated high impacts on native species.
    Xin Chen, Yujue Wang, Yuting Shen, Weiguo Sang, Nengwen Xiao, Chunwang Xiao
    2023, 16 (6): rtad040.
    Abstract ( 28 )   PDF(pc) (1432KB) ( 19 )   Save
    Soil moisture, which is an important factor affecting ecosystem function, can maintain microbial activity and ultimately change the microbial community by altering vegetation diversity and controlling the diffusion and transport of soil nutrients. To explore the effects of soil water content (SWC) on soil prokaryotic community, we established a study area covering a natural soil moisture gradient and subdivided it into high (HW, 4.80 ± 1.18%), medium (MW, 2.17 ± 0.09%) and low water contents (LW, 1.85 ± 0.14%) in the grassland ecosystem along the south shore of Hulun Lake in Inner Mongolia, China. Environmental factors were determined by field surveys and laboratory analyses. Soil prokaryotes were determined by high-throughput sequencing techniques. Vegetation characteristics and soil physicochemical properties had a significant effect on prokaryotic richness diversity, and SWC was the most important factor influencing prokaryotic richness diversity. In the MW, the number of differential prokaryotes was lowest, and prokaryotic microorganisms had the highest diversity and relative abundance at the phylum level, which may reflect less intrinsic variation and higher overall activity of the prokaryotic community in the MW. In addition, HW and LW had lower prokaryotic diversity and relative abundance at the phylum level, and phenotypic predictions for both groups indicated a more tolerant prokaryotic community. In summary, the prokaryotic community responded significantly to the natural moisture gradients in grassland ecosystems along the south shore of Hulun Lake, and both too high and too low soil moisture increased prokaryotic stress resistance.
    Jiangshan Lai, Weijie Zhu, Dongfang Cui, Dayong Fan, Lingfeng Mao
    2023, 16 (6): rtad047.
    Abstract ( 24 )   PDF(pc) (674KB) ( 11 )   Save
    The field of forestry research has greatly benefited from the integration of computational tools and statistical methods in recent years. Among these tools, the programming language R has emerged as a powerful and versatile platform for forestry research, ranging from data analysis, modeling to visualization. However, the key trends in general reported R use and patterns in forestry research remain unknown. We analyzed R and R package usage frequencies for 14 800 research articles published in eight top forestry journals across a span of 10 years, from 2013 to 2022. Among these articles, a notable number of 6790 (accounting for 45.7%) explicitly utilized R as their primary tool for data analysis. The adoption of R exhibited a linear growth trend, rising from 28.3% in 2013 to 60.9% in 2022. The top five used packages reported were vegan, lme4, nlme, MuMIn, and ggplot2. Diverse journals have their unique areas of emphasis, resulting in disparities in the frequency of R package application among journals. The average number of R packages used per article also showed an increasing trend over time. The study underscores the recognition that R, with its powerful data statistical and visualization capabilities, plays a pivotal role in enabling researchers to conduct thorough analyses and acquire comprehensive insights into various aspects of forestry science.
IF: 3.0
5-year IF: 2.5
Editors-in-Chief
Yuanhe Yang
Bernhard Schmid
CN 10-1172/Q
ISSN 1752-9921(print)
ISSN 1752-993X(online)