Purpose
Soil fungi have been proven to influence the plant productivity and community composition of grasslands, but regulation of soil fungi on the responses of plant production-community ...composition relationship to grazing and mowing remains unclear.
Methods
Here, we assessed the functional characteristics of three fungal groups using the Ribosomal Database Project (RDP) classifier and data available in FUNGuild, and we characterized the community of saprotrophic, mycorrhizal, and potential plant pathogenic fungi from surface (0–10 cm) and subsurface soils (10–20 cm) of temperate grasslands, which experienced three management practices, grazing, mowing, and grazing + mowing, respectively.
Results
We found that all three disturbances decreased plant aboveground production and changed plant community composition in grasslands. Compared with the control, grazing significantly reduced the richness of both saprophytic fungi and potential plant pathogens from surface soil, where the richness of saprophytic fungi under grazing + mowing was also significantly reduced. No changes in the richness of mycorrhizal fungi among three disturbances were observed compared to the control in the surface soil, where antagonistic interaction between potential plant pathogens and saprotrophic fungi drove the plant production-community composition relationship. On the contrary, three disturbances did not change the richness of all fungal functional guilds in the subsurface soil, where the plant production-community composition relationship was driven by antagonistic interaction between mycorrhizal fungi and potential plant pathogens.
Conclusion
The findings reveal that antagonistic interaction between fungal guilds played important roles in regulating response of plant production-community composition to grazing and mowing in grasslands. Our finding highlights that potential plant pathogens also have a crucial effect on plant production-community composition relationship. This knowledge is important for predicting the shifts in ecosystem functions as consequence of changes in soil fungal groups during grassland management.
Forage-grain ratoon rice (FG-RR) is a dual-cropping system, with forage harvested in the initial season and grain during the regeneration phase. While it is known that the timing of mowing and ...nitrogen (N) fertilization are key drivers that influence FG-RR production, physiological mechanisms ensuing mowing and N fertilizer application remain unclear. We conducted field experiments in 2021 and 2022 to investigate the yield and growth characteristics of ratooned crops (RC) under various mowing treatments (heading, milk-ripening, dry-ripening and maturity) using three N levels (135, 270, and 405 kg ha−1), two rice genotypes, Taoyouxiangzhan (TYXZ) and Liangyou 6326 (LY6326). Our results demonstrate a significant increase in ratoon yield when mowing occurred at heading or milk-ripening stages compared with maturity, with a yield increase of 2.2-fold when mowing occurred at heading. Early mowing stages increased stubble biomass (up to 73 %) and non-structural carbohydrate (up to 198 %) compared with that at maturity. Mowing at heading or milk-ripening improved accumulated temperature and light exposure, and when coupled with higher N application (270 kg ha−1 N), amplified ratoon ability to recover. Collectively, these factors raised leaf area index, canopy light interception and biomass. Hierarchical partitioning analysis underscored the substantial yet indirect influence of environmental drivers of ratoon yield, alongside a direct driver of growth, particularly thermal sum. We conclude that mowing at heading and milk-ripening with 270 kg ha−1 N elicits optimal ratoon yield with forage production, although further studies are required to determine how these guidelines vary across environments.
•Early mowing and optimize N fertilizer elicit higher forage quality & ratoon yield.•Improvement of ratoon yield attribute to high panicle number.•Environmental factors primarily thermal sum drive ratoon yield formation.
Invasive plant species can hinder the establishment and growth of native plants and impact several ecosystem properties, such as soil cover, nutrient cycling, fire regimes and hydrology. Controlling ...invasive plants is then a necessary, yet usually expensive, step towards the restoration of an ecosystem. A synthesis of literature is needed to understand variation in invasive plants' impacts and their practical control in restoration contexts, and to identify associated knowledge gaps.
We reviewed 372 articles published from 2000 to 2019 covering the control of undesirable plants (both exotic invasive and overabundant native plant species) in ecological restoration to gather information on the main plants being controlled and methods used, and considering the distribution of studies among biomes and countries grouped according to the Human Development Index (HDI).
Grasses and forbs were the most‐studied invasive plant species in restoration sites, but invasive trees were well studied in the tropics. Poaceae and Asteraceae were the most studied families of invasive plants. Non‐chemical interventions (mostly mowing and prescribed fire) were used in more than half of the reviewed studies globally, but chemical methods (mainly glyphosate spraying, used in 40% of projects using herbicides) are also common. The reviewed studies were mostly performed in countries with very high HDI. Countries with low and medium HDI used only non‐chemical methods.
Synthesis and applications. Decisions about which control method to use depend heavily on the invasive plant species' growth forms, the local economic situation where the restoration sites are located and resources available for control. More developed countries tend to use more chemical control, whereas less developed ones use mainly non‐chemical methods. Since most of the reviewed studies were performed in countries with very high HDI, we lack information from developing countries, which concentrates global hotspots for biodiversity conservation and global commitments of forest and landscape restoration.
Resumo
Plantas invasoras podem impedir o estabelecimento e o crescimento de plantas nativas e afetar diversas propriedades dos ecossistemas, como cobertura de solo, ciclagem de nutrientes, regimes de fogo e hidrologia. O controle de plantas invasoras, ainda que oneroso, é uma etapa necessária para restauração de muitos ecossistemas. Desta forma, sintetizar literatura existente sobre plantas invasoras em experimentos de restauração pode auxiliar na compreensão dos impactos e controle prático destas no contexto da restauração ecológica, bem como identificar lacunas de conhecimento.
Nós revisamos 372 artigos, publicados entre os anos 2000–2019, que contemplaram o controle de plantas invasoras (espécies exóticas invasoras ou nativas superabundantes) na restauração ecológica, para sintetizar informações sobre as principais plantas controladas e métodos de controle utilizados. As informações foram agrupadas considerando o bioma, local e Índice de Desenvolvimento Humano (IDH) onde os experimentos foram conduzidos.
Gramíneas e arbusto‐arbustivas apresentaram a maior frequência de ocorrência como plantas invasoras na restauração em todos os biomas analisados, mas espécies arbóreas invasoras foram também muito controladas nos trópicos. Poaceae e Asteraceae foram as famílias de plantas invasoras mais estudadas. Métodos de controle não químico (principalmente roçada e fogo) foram utilizados em mais da metade dos estudos revisados, porém, métodos químicos (principalmente pulverização com glifosato, usado em 40% dos projetos que usaram herbicidas) também foram comuns. A maioria dos estudos revisados foram realizados em países com IDH muito alto. Países com baixo e médio IDH utilizaram somente controle não‐químico.
Sínteses e aplicações. Decisões sobre qual método de controle utilizar dependeram do tipo de espécies invasora, da situação econômica do local onde se planeja fazer a restauração e dos recursos disponíveis. Países mais desenvolvidos tendem a usar mais métodos de controle químico, enquanto aqueles os pouco desenvolvidos utilizaram somente controle não‐químico. Como a maioria dos estudos foram realizados em países com Índice de Desenvolvimento Humano muito alto, se faz necessário mais informações acerca dos países em desenvolvimento, os quais concentram hotspots de biodiversidade para conservação e compromissos globais de restauração.
Decisions about which control method to use depend heavily on the invasive plant species' growth forms, the local economic situation where the restoration sites are located and resources available for control. More developed countries tend to use more chemical control, whereas less developed ones use mainly non‐chemical methods. Since most of the reviewed studies were performed in countries with very high Human Development Index, we lack information from developing countries, which concentrates global hotspots for biodiversity conservation and global commitments of forest and landscape restoration.
The world's grasslands, both natural and managed, provide food and many non-provisioning ecosystem services. Although most grasslands today are used for livestock grazing or fodder production, little ...is known about the spatial patterns of grassland management intensity, especially at broad geographic scales. Using the European Union as a case study, we mapped mowing frequency as a key indicator of grassland management intensity. We used MODIS NDVI time series from 2000-2012 to map mowing frequency using a spline-fitting algorithm that detects up to five mowing events within a single growing season. We combined mowing frequency maps with existing maps of livestock distribution and grassland management frequency to identify clusters of similar grassland management intensity across Europe. Our results highlight generally high mowing frequency in areas of high grassland productivity, especially in Ireland, northern and central France, and the Netherlands. Our analyses also show distinct clusters of similar grassland management, representing different grassland-management intensity regimes. High intensity clusters occurred particularly in western and southern Europe, especially in Ireland, in the northern and central parts of France and Spain, and the Netherlands but also in northern and southern Germany and eastern Poland. Low intensity clusters were found mainly in central and eastern Europe and in mountainous regions but also in Extremadura in Spain, Wales and western England (UK). Generally, our analyses emphasize the usefulness of jointly using satellite time series and agricultural statistics to monitor grassland intensity across broad geographic extents. Our maps allow for a new, spatially-detailed view of management intensity in grassland systems and may help to improve regionally targeted land-use and conservation policies.
Stagnant yields and declining soil health are common characteristics of high-intensity, low-residue cropping systems, such as potato, particularly in northeastern North America. Incorporating ...cultural practices including cover cropping and manure application is a way to combat declines in agroecosystem health and potato productivity. However, manure application and the use of cover crops may exacerbate weed issues through seedbank additions.
This study was aimed at investigating how the cultural practices of cover cropping and manure application and their associated management activities can alter weed community dynamics and weed seedbank composition in a northeastern North American potato rotation.
The study evaluated the use of eight cover crop mixtures—annual and perennial grasses and legumes—grown over two years with/without manure added in year one of the rotation. It also examined the effects of the cover crop mixtures and the presence/absence of manure on the weed community and on seedbank dynamics within a three-year potato rotation between 2019 and 2021.
In year one of the study and directly after application, manure plots had greater weed seedbank density and species richness; however, this did not result in greater in-season weed biomass. Manure application resulted in a gradual decline in weed seedbank density over time regardless of cover crop treatment. Further, manure application increased the in-season competitive ability of cover crops, resulting in greater weed suppression per unit of cover crop biomass. In contrast, in the absence of manure, weed seedbank density remained largely unchanged through time regardless of cover crop treatment. We found that management practices associated with annual and perennial cover crops had distinct ecological filtering effects throughout the rotation on the weed community and prevented the dominance of any particular species.
Together, our results demonstrate that combining the cultural practices of annual or perennial cover cropping and manure application contributes to weed suppression and should be considered an important component of sustainable potato production.
•We studied the use of cover crops and manure application on weed community dynamics.•Manure applied in year one added weed seeds yet did not increase weed pressure.•Manure improved competitive ability of cover crops and led to a continuous decline in the weed seedbank.•Diversified management practices associated with cover crops had species specific effects on weeds.•Our results support the use of cultural practices to build a sustainable potato rotation.
Governments pay agencies to control the activities of farmers who receive governmental support. Field visits are costly and highly time-consuming; hence remote sensing is widely used for monitoring ...farmers' activities. Nowadays, a vast amount of available data from the Sentinel mission significantly boosted research in agriculture. Estonia is among the first countries to take advantage of this data source to automate mowing and ploughing events detection across the country. Although techniques that rely on optical data for monitoring agriculture events are favourable, the availability of such data during the growing season is limited. Thus, alternative data sources have to be evaluated. In this paper, we developed a deep learning model with an integrated reject option for detecting grassland mowing events using time series of Sentinel-1 and Sentinel-2 optical images acquired from 2000 fields in Estonia in 2018 during the vegetative season. The rejection mechanism is based on a threshold over the prediction confidence of the proposed model. The proposed model significantly outperforms the state-of-the-art technique and achieves event accuracy of 73.3% and end of season accuracy of 94.8%.
•Litter from grazing grassland had the highest decomposition rate.•All litter types showed greater decomposition rate in enclosed than used grasslands.•Litter decomposition rate is positively ...correlated with soil moisture in habitat.•No home-field advantage in litter decomposition across grassland-use types.
Litter decomposition is a key process of nutrient cycling in ecosystems, and has been studied in a wide range of grasslands, including the steppes on the Mongolian Plateau. However, information is hardly available on the responses of grassland litter decomposition to different land-use types, especially if the litters produced from grazing or mowing grasslands have home-field advantage in decomposition. In a five-year field experiment examining the effects of land-use types on grassland ecosystems in central Inner Mongolia, we determined the litter decomposition rate and quality indicators of three dominant steppe plants (Leymus chinensis, Stipa krylovii and Cleistogenes squarrosa) produced in grazing, mowing or enclosed grasslands, both in their respective home habitats versus in reciprocally displaced habitats. We found that (i) the litters from the grazing grassland had higher decomposition rate than that from enclosed grassland, especially when all litters were placed in the enclosed grassland; and the decomposition rate was negatively related with the C/N ratio, lignin concentration and lignin/N ratio in litters (P < 0.001). (ii) During the two-year decomposition period, the mass loss rates, and the difference in mass loss rates of grazing litters between in situ and displaced habitats, were the highest in the first summer period (June-November). (iii) Compared to the decomposition in situ, the litters from grazing or mowing grasslands decomposed apparently faster when being displaced in enclosed grassland, whereas the litters from enclosed grassland decomposed significantly slower (P < 0.05) when being displaced in grazing or mowing grasslands. The faster decomposition in enclosed grassland was associated with the better soil moisture. No home-field advantage is shown in the decomposition of steppe plants across land-use types in the studied grassland, possibly due to the non-significant divergence in soil microbial communities over the five-year experimental period. Our results indicate that the effects on litter decomposition of the soil moisture variation between the grazing/mowing and the enclosed grasslands, is greater than the effects of the variation in litter quality and possibly in microbial communities across different land-use types. Further HFA studies to involve the variation in soil microbial communities are warranted.
Endophytic bacteria are critical for plant growth and health. However, compositional and functional responses of bacterial endophyte communities towards agricultural practices are still poorly ...understood. Hence, we analyzed the influence of fertilizer application and mowing frequency on bacterial endophytes in three agriculturally important grass species. For this purpose, we examined bacterial endophytic communities in aerial plant parts of Dactylis glomerata L., Festuca rubra L., and Lolium perenne L. by pyrotag sequencing of bacterial 16S rRNA genes over two consecutive years. Although management regimes influenced endophyte communities, observed responses were grass species-specific. This might be attributed to several bacteria specifically associated with a single grass species. We further predicted functional profiles from obtained 16S rRNA data. These profiles revealed that predicted abundances of genes involved in plant growth promotion or nitrogen metabolism differed between grass species and between management regimes. Moreover, structural and functional community patterns showed no correlation to each other indicating that plant species-specific selection of endophytes is driven by functional rather than phylogenetic traits. The unique combination of 16S rRNA data and functional profiles provided a holistic picture of compositional and functional responses of bacterial endophytes in agricultural relevant grass species towards management practices.
Managed grasslands cover about one third of the European utilized agricultural area. Appropriate grassland management is key for balancing trade-offs between provisioning and regulating ecosystem ...services. The timing and frequency of mowing events are major factors of grassland management. Recent studies have shown the feasibility of detecting mowing events using remote sensing time series from optical and radar satellites. In this study, we present a new method combining the regular observations of Sentinel-1 (S1) and the better accuracy of Sentinel-2 (S2) grassland mowing detection algorithms. This multi-source approach for grassland monitoring was assessed over large areas and in various contexts. The method was first validated in six European countries, based on Planet image interpretation. Its performances and sensitivity were then thoroughly assessed in an independent study area using a more precise and complete reference dataset based on an intensive field campaign. Results showed the robustness of the method across all study areas and different types of grasslands. The method reached a F1-score of 79% for detecting mowing events on hay meadows. Furthermore, the detection of mowing events along the growing season allows to classify mowing practices with an overall accuracy of 69%. This is promising for differentiating grasslands in terms of management intensity. The method could therefore be used for large-scale grassland monitoring to support agri-environmental schemes in Europe.
Display omitted
•Grassland mowing detection method developed for the Sen4CAP open source toolbox.•Validated in seven European countries through image interpretation and field data.•Combined use of Sentinel-1 and Sentinel-2 increases detection accuracy.•High performances and transferability for large scale grassland monitoring.
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