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While it is known that interactions between plants and soil fungi drive many essential ecosystem functions, considerable uncertainty exists over the drivers of fungal community composition in the rhizosphere. Here, we examined the roles of plant species identity, phylogeny and functional traits in shaping rhizosphere fungal communities and tested the robustness of these relationships to environmental change. We conducted a glasshouse experiment consisting of 21 temperate grassland species grown under three different environmental treatments and characterised the fungal communities within the rhizosphere of these plants. We found that plant species identity, plant phylogenetic relatedness and plant traits all affected rhizosphere fungal community composition. Trait relationships with fungal communities were primarily driven by interactions with arbuscular mycorrhizal fungi, and root traits were stronger predictors of fungal communities than leaf traits. These patterns were independent of the environmental treatments the plants were grown under. Our results showcase the key role of plant root traits, especially root diameter, root nitrogen and specific root length, in driving rhizosphere fungal community composition, demonstrating the potential for root traits to be used within predictive frameworks of plant–fungal relationships. Furthermore, we highlight how key limitations in our understanding of fungal function may obscure previously unmeasured plant–fungal interactions.

The extreme species richness of some temperate grasslands is a globally relevant yet understudied phenomenon. Until now, few records from thoroughly sampled, though not permanently fixed, vegetation plots were available. We therefore established a network of 40 permanent 4 × 4-m2 plots in species-rich grasslands of the White Carpathians (Czechia), Ukraine, Hungary and Romania. Thirty-one of them form the main dataset comprising plots from discrete forest-steppe grasslands (the Brachypodio-Molinietum association of the Cirsio-Brachypodion pinnati alliance), while nine of them forms the local dataset from a single locality in the White Carpathians, whose vegetation lacks most forest-steppe species and is transitional between the Bromion erecti and Arrhenatherion elatioris alliances (the Anthoxantho-Agrostietum and Anthyllido vulnerariae-Trifolietum montani associations). The permanent plots contain a nested subplot of 1 m2, except for five plots from Ukraine and Romania. Most plots harboured at least 80 vascular plant species per 16 m2, with the mean richness of 16-m2 plots was 95.3 species in the main dataset and 84 species in the local dataset. Mean richness of the 1-m2 subplots, presumably reflecting local environmental conditions and competitive relationships more than that of 16 m2 plots, did not vary between the two datasets, with a general mean of 57.6 species. Species counts of 16-m2 plots and 1-m2 subplots correlated, albeit only moderately, only in the main dataset. The presented datasets may be used for comparative analyses as well as for a future revisiting of the plots and may bring novel insights into the dynamics of extreme species richness.

While northern temperate grasslands are important for supporting beef production, it remains unclear how grassland above- and belowground biomass responds to long-term cattle grazing. Here, we use a comprehensive dataset from 73 grasslands distributed across a broad agro-climatic gradient to quantify grassland shoot, litter, and shallow (top 30 cm) root biomass in areas with and without grazing. Additionally, we relate biomass to soil carbon (C) concentrations. Forb biomass was greater (p −1 for grazed vs. 2210 kg ha−1 for non-grazed; p > 0.05). Forb crude protein concentrations were lower (p −1) and without (7130 kg ha−1) grazing (p > 0.05). Surface mineral soil C concentrations were positively related to peak grassland biomass, particularly total (above + belowground) biomass, and with increasing forb biomass in grazed areas. Finally, total aboveground shoot biomass and soil C concentrations in the top 15 cm of soil were both positively related to the proportion of introduced plant diversity in grazed and non-grazed grasslands. Overall, cattle grazing at moderate stocking rates had minimal impact on peak grassland biomass, including above- and belowground, and a positive contribution exists from introduced plant species to maintaining herbage productivity and soil C.

Monitoring biomass yield in grassland is of key importance to support sustainable management decisions. Especially the high spatio-temporal variety in grasslands requires rapid and cost-efficient data acquisition with a high spatial and temporal resolution. Therefore, this study aims to evaluate the comparability of UAV-based simultaneously acquired vegetation indices from a consumer-grade RGB-camera (Sony Alpha 6000) and a well-calibrated narrow-band multispectral camera (MicaSense RedEdge-M) to estimate dry matter biomass yield. The study site is an experimental grassland field in Germany with four nitrogen fertilizer levels. Biomass yield and UAV-based data for the first cut in May 2018 was analysed in this study. From the RGB-data the Plant Pigment Ratio Index (PPR) and the Normalized Green Red Difference Index (NGRDI) and from the multispectral data the Normalized Difference Vegetation Index (NDVI) are calculated as predictors for dry biomass yield. The NGRDI and NDVI perform moderately well with cross-validation R2 of 0.57 and 0.63 respectively, while the PPR performs better with an R2 of 0.70. These results indicate the potential of low-cost UAV-based methods for rapid assessment of grasslands.

Soil organic carbon (SOC) is an important carbon pool susceptible to land‐use change (LUC). There are concerns that converting grasslands into the C4 bioenergy crop Miscanthus (to meet demands for renewable energy) could negatively impact SOC, resulting in reductions of greenhouse gas mitigation benefits gained from using Miscanthus as a fuel. This work addresses these concerns by sampling soils (0–30 cm) from a site 12 years (T12) after conversion from marginal agricultural grassland into Miscanthus x giganteus and four other novel Miscanthus hybrids. Soil samples were analysed for changes in below‐ground biomass, SOC and Miscanthus contribution to SOC (using a 13C natural abundance approach). Findings are compared to ECOSSE soil carbon model results (run for a LUC from grassland to Miscanthus scenario and continued grassland counterfactual), and wider implications are considered in the context of life cycle assessments based on the heating value of the dry matter (DM) feedstock. The mean T12 SOC stock at the site was 8 (±1 standard error) Mg C/ha lower than baseline time zero stocks (T0), with assessment of the five individual hybrids showing that while all had lower SOC stock than at T0 the difference was only significant for a single hybrid. Over the longer term, new Miscanthus C4 carbon replaces pre‐existing C3 carbon, though not at a high enough rate to completely offset losses by the end of year 12. At the end of simulated crop lifetime (15 years), the difference in SOC stocks between the two scenarios was 4 Mg C/ha (5 g CO2‐eq/MJ). Including modelled LUC‐induced SOC loss, along with carbon costs relating to soil nitrous oxide emissions, doubled the greenhouse gas intensity of Miscanthus to give a total global warming potential of 10 g CO2‐eq/MJ (180 kg CO2‐eq/Mg DM).

Trifolium is the most used pastoral legume genus in temperate grassland systems, and a common feature in meadows and open space areas in cities and parks. Breeding of Trifolium spp. for pastoral production has been going on for over a century. However, the breeding targets have changed over the decades in response to different environmental and production pressures. Relatively small gains have been made in Trifolium breeding progress. Trifolium breeding programmes aim to maintain a broad genetic base to maximise variation. New Zealand is a global hub in Trifolium breeding, utilising exotic germplasm imported by the Margot Forde Germplasm Centre. This article describes the history of Trifolium breeding in New Zealand as well as the role and past successes of utilising genebanks in forage breeding. The impact of germplasm characterisation and evaluation in breeding programmes is also discussed. The history and challenges of Trifolium breeding and its effect on genetic gain can be used to inform future pre-breeding decisions in this genus, as well as being a model for other forage legumes.

Grassland ecosystems account for approximately 40% of terrestrial biomes globally. These communities are characterized by a large allocation to belowground biomass, often exceeding its aboveground counterpart. However, this biomass investment cannot be entirely attributed to the acquisitive function of roots. Grassland plants also allocate to non-acquisitive, stem-derived, belowground organs, such as rhizomes. These organs are responsible for the key plant functions of space occupancy, resprouting after damage, and seasonal rest. However, biomass investment to rhizomes has rarely been studied. Here we gathered community-level aboveground and rhizome biomass data for 52 temperate grasslands in Czech Republic (Central Europe), differing in management intensity. We found that rhizome biomass scaled linearly with aboveground biomass, and more intensive management disproportionally (negatively) affected rhizome biomass. This finding may have important implications for the persistence of temperate grassland plants and their provision of ecosystem services (e.g., soil carbon sequestration, soil stabilization) in relation to changing environments.

Botanical gardens have contributed to plant conservation through the maintenance of both living and preserved plant specimens for decades. However, there is still a large gap in the literature with regards to understanding the potential conservation value botanical gardens could provide for local pollinators. We investigated how plant-pollinator community structure and diversity may differ between botanical gardens and native habitats by sampling and comparing between two environments: a restored native grassland patch within a local botanical garden and fifteen native, remnant temperate grassland sites in the Northern Great Plains. We found pollinator diversity within the restored native grassland patch was greater than 55% of total remnant temperate grassland transects throughout the entire flowering season, while plant diversity and network community metrics between the two environments remained similar throughout, except that remnant prairies have more links (higher connectance) with pollinators than the garden patch. Overall, our findings demonstrate the promising role restored native grassland patches in botanical gardens could play as reservoirs for local pollinator communities by supporting plant-pollinator interactions comparable to those found in native habitat remnants in the same region.

Community structure contributes to ecosystem persistence and stability. To understand the mechanisms underlying pollination and community stability of natural areas in a human influenced landscape, a better understanding of the interaction patterns between plants and pollinators in disturbed landscapes is needed. The Northern Great Plains still retain extensive tracts of remnant temperate grassland habitat within a matrix of varying land-uses. We used a network-based approach to quantify how temperate grassland attributes and landscape heterogeneity influence plant-pollinator community structure in natural habitats. We also quantified pollinator diversity and floral diversity to assess the functional role of temperate grassland attributes and the surrounding landscape on the composition of the plant-pollinator communities in natural habitats. We found that the amount of local nectar sugar and increased proportions of certain land-uses contribute to pollinator diversity that in turn influences the structure of interactions between plants and pollinators. Understanding the factors contributing to plant-pollinator network structure can guide management decisions to support resilient plant-pollinator communities and conserve the stability of pollination services.

Nitrogen enrichment modifies both plant communities and ecosystem services. It remains unclear how plant species networks will be affected by nitrogen enrichment. We present and compare species networks based on replicated experimental plant communities under different nitrogen addition rates and frequencies. We found that nonrandom assembly rules and specific four-species combinations have temporal stability, but nitrogen enrichment reduced the correlation number of dominant species combinations at the two frequencies considered, and the effect of low-frequency nitrogen addition on this number was much greater than that of high-frequency nitrogen addition. Regardless of nitrogen enrichment level, all the species networks considered exhibited nonrandomness, small-worldness, and non-scale-freeness, which were partly attributable to close species interactions. We also found that the clustering coefficient increased and the average path length decreased under elevated nitrogen addition rates from 0 to 5 g N m−2 year−1, but these two indices showed no pattern from 10 to 50 g N m−2 year−1. Importantly, nitrogen enrichment altered species network structure, especially changing the important position of Cleistogenes squarrosa, which revealed that this species is more sensitive than others to nitrogen enrichment. These results revealed variability in species networks and species combination stability under elevated nitrogen, which may help us understand changes in temperate ecosystems in the face of anthropogenic nitrogen enrichment.

Background Refaunation/rewilding by large ungulates represents a cost-efficient approach to managing natural biotopes and may be particularly useful for areas whose biodiversity depends on disturbance dynamics and is imperilled by successional changes. To study impacts of refaunation on invertebrates, we focused on butterflies inhabiting the former military training range Milovice, Czech Republic, refaunated since 2015 by a combination of Exmoor pony (“wild” horse), Tauros cattle (“aurochs”), and European wisent. Methods We analysed butterfly presence-absence patterns immediately after the military use termination (early 1990s), prior to the refaunation (2009), and after it (2016–19); and current abundance data gained by monitoring butterflies at refaunated and neglected plots. We used correspondence analysis for the presence-absence comparison and canonical correspondence analysis for the current monitoring, and related results of both ordination methods to the life history and climatic traits, and conservation-related attributes, of recorded butterflies. Results Following the termination of military use, several poorly mobile species inclining towards oceanic climates were lost. Newly gained are mobile species preferring warmer continental conditions. The refaunated plots hosted higher butterfly species richness and abundances. Larger-bodied butterflies developing on coarse grasses and shrubs inclined towards neglected plots, whereas refaunated plots supported smaller species developing on small forbs. Conclusion The changes in species composition following the cessation of military use were attributable to successional change, coupled with changes in species pool operating at larger scales. By blocking succession, large ungulates support butterflies depending on competitively poor plants. Restoring large ungulates populations represents a great hope for conserving specialised insects, provided that settings of the projects, and locally adapted ungulate densities, do not deplete resources for species with often contrasting requirements.

Wildfire activity has surged in North America’s temperate grassland biome. Like many biomes, this system has undergone drastic land-use change over the last century; however, how various land-use types contribute to wildfire patterns in grassland systems is unclear. We determine if certain land-use types have a greater propensity for large wildfire in the U.S. Great Plains and how this changes given the percentage of land covered by a given land-use type. Almost 90% of the area burned in the Great Plains occurred in woody and grassland land-use types. Although grassland comprised the greatest area burned by large wildfires, woody vegetation burned disproportionately more than any other land-use type in the Great Plains. Wildfires were more likely to occur when woody vegetation composed greater than 20% of the landscape. Wildfires were unlikely to occur in croplands, pasture/hay fields, and developed areas. Although these patterns varied by region, wildfire was most likely to occur in woody vegetation and/or grassland in 13 of 14 ecoregions we assessed. Because woody vegetation is more conducive to extreme wildfire behaviour than other land-use types in the Great Plains, woody encroachment could pose a large risk for increasing wildfire exposure. Regional planning could leverage differential wildfire activity across land-uses to devise targeted approaches that decrease human exposure in a system prone to fire.

Oomycetes are an ubiquitous protistan lineage including devastating crop parasites. Although their ecology in agrosystems has been widely studied, little is known of their distribution in natural and semi-natural ecosystems. We provide here a baseline of the diversity and distribution of soil oomycetes, classified by lifestyles (biotrophy, hemibiotrophy and saprotrophy), at the landscape scale in temperate grassland and forest. From 600 soil samples, we obtained 1,148 Operational Taxonomy Units representing ∼20 million Illumina reads (region V4, 18S rRNA gene). We found a majority of hemibiotrophic plant pathogens, which are parasites spending part of their life cycle as saprotrophs after the death of the host. Overall both grassland and forest constitute an important reservoir of plant pathogens. In forests, relative abundances of obligate biotrophs and hemibiotrophs differed between regions and showed opposite responses to edaphic conditions and human-induced management intensification, suggesting different ecological requirements for these two functional guilds.

Soil carbon (C) availability may play a crucial role in regulating how soil respiration responds to the increase of nitrogen (N) inputs. However, the related research is sporadic so far and has not adequately verified this speculation or addressed the topic in a widespread temperate grassland ecosystem. This lack of knowledge hinders our further accurate prediction of C emissions from terrestrial ecosystems. To improve our knowledge of the role of soil C resources in regulating Rs responses to N inputs, we established a situ field experiment with three levels of N addition (0, 50, and 100 kg N ha−1 yr−1) and two levels of glucose (G) addition (0 and 480 kg C ha−1 yr−1) to determine the Rs dynamics in a temperate semiarid grassland in China. The results showed that only N addition had no significant effects on Rs as well as microbial biomass C (MBC) during our 168-hour observation period, whereas G addition and G addition together with N addition had positive effects on Rs and MBC. The regression analysis further showed that the cumulative CO2 efflux was significantly positively related to soil MBC concentrations during the 168-hour observation period. Altogether, our findings verify that soil C availability is an important driver affecting the Rs response to N addition. No response of Rs to increased N availability resulting from N input was attributed to microbial C limitation in a semiarid grassland during a 168-hour observation.

Accurate predictions of water vapor at large temporal and spatial scales are particularly important in global studies. In recent years, Central Asian grasslands have been subject to both intensive grazing and variability in climatic conditions. However, uncertainties about grazing on water cycling under climate change still exist. Therefore, the Biome-BGC grazing model was applied to assess the effects of grazing on evapotranspiration (ET) and water use efficiency (WUE). Three grassland types were studied during the period 1979–2011: forest meadow (FM), temperate grassland (TG) and desert grassland (DG). ET shows a gradual decreasing trend from FM (365.65 ± 36.86 mm m−2 yr−1) to DG (183.32 ± 21.15 mm m−2 yr−1), and WUE ranging from 0.62 ± 0.03 g C kg-1 H2O in FM to 1.12 ± 0.10 g C kg−1 H2O in TG, with an average of 0.83 ± 0.05 g C kg−1 H2O. Although there was a significant decrease in ET of 1.47–2.72 mm m−2 yr−1, WUE increased at a rate of 0.004 g C kg−1 H2O yr−1 in Central Asia. From 1979 to 2011, grazing lowered ET by 7.47% in Central Asia; the reduction rates for FM, TG and DG were 3.10%, 12.70% and 7.42%, respectively. In general, grazing decreased WUE by 3.60%. From non-grazed to grazed scenario, WUE increased by 6.86% for FM, but WUE decreased by 7.27% and 5.61% for TG and DG. An over-compensation of GPP under grazing might account for the higher WUE under certain grazing intensities. In order to achieve maximum utilization of water efficiency, proper grazing intensity for TG, DG and FM should be limited to 0.17, 0.39 and 0.38 head/ha, respectively.

Grassland productivity is the most direct indicator of grassland’s ecological status; thus, precise and rapid estimation of grassland productivity has an important significance for evaluating regio...

In support of natural resource agencies in Canada, the United States, and Mexico, we report on a series of component analyses and an updated Landscape Conservation Design for temperate grassland conservation. We targeted 12 major grassland ecosystem types that occur across the Great Plains and Chihuahuan Desert regions. Component analyses included (1) documenting long-term trends in extent by grassland type, (2) identifying species of concern associated with the major grassland types, (3) documenting current protected areas including each grassland type, (4) assessing landscape intactness and connectivity among grassland areas, and (5) identifying Grassland Potential Conservation Areas (GPCAs) to advance grassland conservation. Most severe declines in grassland extent have occurred in tallgrass prairie types, followed by mixed-grass, shortgrass, and semi-desert grasslands. Similar trends by type were documented for landscape intactness and connectivity. Some 174 species of vertebrates, invertebrates, and plants considered by NatureServe as critically imperiled, imperiled, or vulnerable are strongly associated with these grassland types, and 103 are listed under protective legislation in one or more countries. Just 1.2% of historic extent for all types combined is currently found within designated protected areas. A total of 177 GPCAs were identified to represent grassland type diversity in areas least likely to conflict with other land uses. Within identified GPCAs, type-specific representation varied from a low of just 1% of historic extent for Texas Blackland Tallgrass Prairie to a high of 27% for Western Great Plains Sand Prairie. Combined across all 12 grassland types, 15% of historic extent is represented.

The ACT Government funded this research and provided access to the nature reserve and management information, Michael Mulvaney, Geoff King, Joel Patterson, Andrew Halley and Richard Milner in particular. JAC acknowledges support from the Australian Research Council (DE120102221) and ARC Centre of Excellence for Environmental Decisions.

Grassland systems frequently exhibit small-scale botanical and structural heterogeneity with pronounced spatio-temporal dynamics. These features present particular challenges for sensor applications, in addition to limitations posed by the high cost and low spatial resolution of many available remote-sensing (RS) systems. There has been little commercial application of RS for practical grassland farming. This article considers the developments in sensor performance, data analysis and modelling over recent decades, identifies significant advances in RS for grassland research and practice and reviews the most important sensor types and corresponding findings in research. Beside improvements of single sensor types, the development of systems with complementary sensors is seen as a very promising research area, and one that will help to overcome the limitations of single sensors and provide better information about grassland composition, yield and quality. From an agronomic point of view, thematic maps of farm fields are suggested as the central outcome of RS and data analysis. These maps could represent the relevant grassland features and constitute the basis for various farm management decisions at strategic, tactical and operational levels. The overarching goal will be to generate low cost, appropriate and timely information that can be provided to farmers to support their decision-making.

Rapid changes in wildfire patterns are documented globally, increasing pressure to identify regions that may experience increases in wildfire in future decades. Temperate grassland and savanna biomes were some of the most frequently burned regions on Earth, however large wildfires have been largely absent from the Great Plains of North America over the last century. In this paper, we conduct an in-depth analysis of changes in large wildfire (>400 ha) regime characteristics over a 30 year period across the Great Plains. For the entire biome, (i) the average number of large wildfires increased from 33.4 + 5.6 per year from1985-1994 to 116.8 + 28.8 wildfires per year from 2005-2014, (ii) total area burned by large wildfires increased 400%, (iii) over half the ecoregions had greater than a 70% probability of a large wildfire occurring in the last decade, and (iv) seasonality of large wildfires remained relatively similar.

Department of Agriculture, Environment and Rural Affairs in Northern Ireland, the Teagasc Walsh Fellowship Scheme peer-reviewed In temperate grassland, urea has been shown to have lower nitrous oxide emissions compared to ammonium nitrate-based fertilizer and is less expensive. However, nitrogen (N) loss via ammonia volatilization from urea raises questions regarding yield performance and efficiency. This study compares the yield and N offtake of grass fertilized with urea, calcium ammonium nitrate (CAN) and urea treated with the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) at six site-years. Five annual fertilizer N rates (100–500 kg N/ha) were applied in five equal splits of 20–100 kg N/ha during the growing season. On average, urea produced slightly better yields than CAN in spring (103.5% of CAN yield) and slightly poorer yields in summer (98.4% of CAN yield). There was no significant difference in annual grass yield between urea, CAN and urea + NBPT. Urea had the lowest cost per tonne of DM grass yield produced. However, the urea treatment had lower N offtake than CAN and this difference was more pronounced as the N rate increased. There was no difference in N offtake between urea + NBPT and CAN. While this study shows that urea produced yields comparable to CAN, urea apparent fertilizer N recovery (AFNR) tends to be lower. Urea selection in place of CAN will increase national ammonia emissions which is problematic for countries with targets to reduce ammonia emissions. Promisingly, NBPT allows the agronomic performance of urea to consistently equal CAN across N rates by addressing the ammonia loss limitations of urea. Department of Agriculture, Environment and Rural Affairs in Northern Ireland Teagasc Walsh Fellowship Programme Department of Agriculture, Food and the Marine

Pasture renewal (or pasture renovation) is a common management practice in grass-based production systems aimed at restoring pasture production and forage quality. It is important to understand the impact of pasture renewal on soil organic carbon stocks. Here we report the CO2 and C balance of three blocks of an intensively managed temperate grassland in New Zealand. Two blocks underwent pasture renewal using the spray and direct drill approach (no ploughing), while the third block served as an undisturbed Control. Net ecosystem production (NEP) was measured using eddy covariance, and additional in- and outputs of C (e.g. C in pasture removed by grazers and returned in dung) either measured or estimated. NEPs of the renewed blocks were between 149 and 212 g C m−2 y−1 lower than the NEP of the Control block during the year of pasture renewal. While CO2 sink strength was obviously diminished as a result of pasture renewal, neither renewed block was a source for CO2, presumably due the relatively warm climate which enabled year-round growing conditions. Despite the non-negative NEPs during the year of pasture renewal, both renewed sites were found to lose soil C as indicated by the negative net ecosystem carbon balances (NECBs). NECBs of the renewed blocks were −156 and −222 g C m−2 y−1, compared to a near-neutral NECB of the Control block. Comparison of the findings from the current study on pasture renewal without ploughing to those from an earlier study on pasture renewal including ploughing led to the following conclusions: i) our data did not suggest lower rates of respiratory CO2 losses when spray-and-direct-drill approach was used instead of ploughing; ii) as both the direct CO2 losses due to microbial degradation and the decrease in CO2 uptake through photosynthesis contribute to the total impact of pasture renewal on NEP, the duration of fallow period was found to be important in determining the short-term CO2 losses due to pasture renewal, with shorter fallow period leading to lower net CO2 losses; iii) addition of C in the form of manure, effluent, or extra supplemental feed for cattle may help to reduce the negative impact of pasture renewal on soil C loss at the renewed site.

Recent global-scale studies have revealed intense levels of human activities within many protected areas worldwide. However, these analyses rely on coarse global-scale data, making their utility for informing local-scale conservation action limited. We developed a spatially explicit national human footprint index for Iran, a biologically diverse country in west Asia, based on the latest high-resolution datasets available for human pressures. We assessed the extent and intensity of human pressure within Iranian protected areas, and across the biomes and ecoregions of Iran. We found that almost one-quarter (22%) of officially protected land was under intense human pressure, mostly located in north-west and west of the country. Protected areas within temperate grasslands, savannas, and shrublands are most impacted, with two-third of their area under intense pressure. The findings provide valuable information for targeting management strategies to alleviate human pressures within protected areas, and also act as a comprehensive database to track the state of protected areas through time. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13280-019-01305-8) contains supplementary material, which is available to authorized users.

Grasslands dominate the central regional landscape of the North America, extending from the Canadian prairies south across the Chihuahuan Desert. We describe this grassland diversity, discussing common forms of ecological classification, and highlight the International Vegetation Classification. We then report on a series of analyses and a Landscape Conservation Design for temperate grassland conservation. We targeted 12 major grassland ecosystem types that occur across this region. Component analyses included: (a) documenting long-term trends in extent by grassland type, (b) assessing landscape intactness among grassland areas, and (c) identifying Grassland Potential Conservation Areas to advance grassland conservation. Most severe declines in grassland extent have occurred in tallgrass prairie types, followed by mixed-grass, shortgrass, and semi-desert grasslands. Similar trends by type were documented for landscape intactness and connectivity. A total of 177 Grassland Potential Conservation Areas (GPCAs) were identified to represent grassland type diversity in areas least likely to conflict with other land uses. Within identified GPCAs, type-specific representation varied from a low of just 1% of historic extent for Texas Blackland Tallgrass Prairie to a high of 27% for Western Great Plains Sand Prairie. Combined across all 12 grassland types, 15% of historic extent is represented.

Soil protists are increasingly appreciated as essential components of soil foodwebs; however, there is a dearth of information on the factors structuring their communities. Here we investigate the importance of different biotic and abiotic factors as key drivers of spatial and seasonal distribution of protistan communities. We conducted an intensive survey of a 10m2 grassland plot in Germany, focusing on a major group of protists, the Cercozoa. From 177 soil samples, collected from April to November, we obtained 694 Operational Taxonomy Units representing >6 million Illumina reads. All major cercozoan taxonomic and functional groups were present, dominated by the small flagellates of the Glissomonadida. We found evidence of environmental selection structuring the cercozoan communities both spatially and seasonally. Spatial analyses indicated that communities were correlated within a range of 3.5 meters. Seasonal variations in the abundance of bacterivores and bacteria, followed by that of omnivores suggested a dynamic prey-predator succession. The most influential edaphic properties were moisture and clay content, which differentially affected each functional group. Our study is based on an intense sampling of protists at a small scale, thus providing a detailed description of the biodiversity of different taxa/functional groups and the ecological processes involved in shaping their distribution.

Exploring the biogeographic patterns of soil microbial diversity is critical for understanding mechanisms underlying the response of soil processes to climate change. Using top- and subsoils from an ∼1,500-km temperate grassland transect, we find divergent patterns of microbial diversity and its determinants in the topsoil versus the subsoil. Furthermore, we find important and direct legacy effects of historical climate change on the microbial diversity of subsoil yet indirect effects on topsoil. Our findings challenge the conventional assumption of similar geographic patterns of soil microbial diversity along soil profiles and help to improve our understanding of how soil microbial communities may respond to future climate change in different regions with various climate histories., Biogeographic patterns and drivers of soil microbial diversity have been extensively studied in the past few decades. However, most research has focused on the topsoil, while the subsoil is assumed to have microbial diversity patterns similar to those of the topsoil. Here we compared patterns and drivers of microbial alpha and beta diversity in and between topsoils (0 to 10 cm) and subsoils (30 to 50 cm) of temperate grasslands in Inner Mongolia of China, covering an ∼1,500-km transect along an aridity gradient. Counter to the conventional assumption, we find contrasting biogeographic patterns of diversity and influencing factors for different bacterial and archaeal groups and between depths. While bacterial diversity remains constant or increases with increasing aridity in topsoil and decreases in subsoil, archaeal diversity decreases in topsoil and remains constant in subsoil. Microbial diversity in the topsoil is most strongly influenced by aboveground vegetation and contemporary climate but is most strongly influenced by the factor historical temperature anomaly since the Last Glacial Maximum (LGM) and by soil pH in the subsoil. Moreover, the biogeographic patterns of topsoil-subsoil community dissimilarities vary for different microbial groups and are overall most strongly influenced by soil fertility differences between depths for bacteria and by contemporary climate for archaea. These findings suggest that diversity patterns observed in the topsoil may not be readily applied to the subsoil horizons. For the subsoil in particular, historical climate plays a vital role in the spatial variation of bacterial diversity. Overall, our study provides novel information for understanding and predicting soil microbial diversity patterns at depth. IMPORTANCE Exploring the biogeographic patterns of soil microbial diversity is critical for understanding mechanisms underlying the response of soil processes to climate change. Using top- and subsoils from an ∼1,500-km temperate grassland transect, we find divergent patterns of microbial diversity and its determinants in the topsoil versus the subsoil. Furthermore, we find important and direct legacy effects of historical climate change on the microbial diversity of subsoil yet indirect effects on topsoil. Our findings challenge the conventional assumption of similar geographic patterns of soil microbial diversity along soil profiles and help to improve our understanding of how soil microbial communities may respond to future climate change in different regions with various climate histories.

Taxonomic research is of fundamental importance in conservation management of threatened species, providing an understanding of species diversity on which management plans are based. The grassland earless dragon lizards (Agamidae: Tympanocryptis ) of southeastern Australia have long been of conservation concern but there have been ongoing taxonomic uncertainties. We provide a comprehensive taxonomic review of this group, integrating multiple lines of evidence, including phylogeography (mtDNA), phylogenomics (SNPs), external morphology and micro X-ray CT scans. Based on these data we assign the lectotype of T. lineata to the Canberra region, restrict the distribution of T. pinguicolla to Victoria and name two new species: T. osbornei sp. nov. (Cooma) and T. mccartneyi sp. nov. (Bathurst). Our results have significant conservation implications. Of particular concern is T. pinguicolla , with the last confident sighting in 1969, raising the possibility of the first extinction of a reptile on mainland Australia. However, our results are equivocal as to whether T. pinguicolla is extant or extinct, emphasizing the immediate imperative for continued surveys to locate any remaining populations of T. pinguicolla . We also highlight the need for a full revision of conservation management plans for all the grassland earless dragons.

After the Korean War, human access to the Korean Demilitarized Zone (DMZ) was highly restricted. However, limited agricultural activity was allowed in the Civilian Control Zone (CCZ) surrounding the DMZ. In this study, land cover and vegetation changes in the western DMZ and CCZ from 1919 to 2017 were investigated. Coniferous forests were nearly completely destroyed during the war and were then converted to deciduous forests by ecological succession. Plains in the DMZ and CCZ areas showed different patterns of land cover changes. In the DMZ, pre-war rice paddies were gradually transformed into grasslands. These grasslands have not returned to forest, and this may be explained by wildfires set for military purposes or hydrological fluctuations in floodplains. Grasslands near the floodplains in the DMZ are highly valued for conservation as a rare land type. Most grasslands in the CCZ were converted back to rice paddies, consistent with their previous use. After the 1990s, ginseng cultivation in the CCZ increased. In addition, the landscape changes in the Korean DMZ and CCZ were affected by political circumstances between South and North Korea. Our results provide baseline information for the development of ecosystem management and conservation plans for the Korean DMZ and CCZ. Given the high biodiversity and ecological integrity of the Korean DMZ region, transboundary governance for conservation should be designed.

As a fragile ecological zone, the temperate grassland region of China has experienced dramatic land use/land cover (LULC) changes due to human disturbances. So far, the impacts of LULC change on climate especially the diurnal temperature range (DTR) in this region are still not well understood. Based on the OMR (observation minus reanalysis) method, this study investigated the effects of LULC on DTR in the temperate grassland region of China. Considering the possible uncertainty of the results due to spatial resolution of the reanalysis dataset, two reanalysis datasets with different spatial resolutions were utilized. Results showed that LULC generally contributed to the decline of DTR in the temperate grassland region of China during 1980 to 2005. Due to different warming effects on monthly maximum temperature (Tmax) and minimum temperature (Tmin), grassland and forest tend to slightly decrease monthly DTR (approximately -0.053 to -0.050°C/decade and approximately -0.059 to -0.055°C/decade, respectively), while bare land has a slightly positive effect on DTR (approximately 0.018-0.021°C/decade). By contrast, cropland and urban tend to slightly decrease Tmax, obviously increase Tmin and thus result in a rapid decline of DTR (approximately -0.556 to -0.503°C/decade and approximately -0.617 to -0.612°C/decade, respectively). In the temperate grassland region of China, grassland vegetation changes due to human disturbances can have some effects on DTR mainly by changing the Tmax. Conversion from grassland to cropland could decrease the DTR by slowing down the increase of Tmax. But the conversion from grassland to bare land, as well as the reduction of grassland vegetation cover will increase Tmax, and consequently the DTR. The results suggest that grassland degradation is likely to result in daylight warming and increased DTR in the temperate grassland region of China.

Based on the observation minus reanalysis (OMR) method, this study explored the impacts of grassland vegetation on diurnal temperature range (DTR) in China’s temperate grassland region from 1982 to 2005. Results showed that temperate grassland vegetation generally tended to decrease growing-season DTR, but the degree of influence of vegetation on DTR was different among different grassland types. From 1982 to 2005, the decline of OMR trend in growing-season DTR was the largest for temperate meadow (−0.191 °C/decade), moderate for temperate steppe (−0.093 °C/decade) and the smallest for temperate desert steppe (−0.022 °C/decade). During the whole growing season, grassland vegetation has a similar warming effect on minimum air temperature (Tmin), and the differences in monthly OMR trends of DTR are mainly determined by the effects of vegetation on maximum air temperature (Tmax). For temperate meadow and temperate steppe, there were obvious cooling effects of vegetation on Tmax from July to September due to evaporative cooling feedback, and these cooling effects intensified with the increase of surface vegetation greenness. For temperate desert steppe, due to low vegetation cover and weak cooling feedback, it exerted comparable warming effects on Tmax and Tmin, thus having no significant impact on DTR change in any month.

This study was funded by AGRI-I (RSF 10/SC/716), the LOEWE-excellence program FACE2FACE, and the Walsh Fellowship program. peer-reviewed An increase in mean soil surface temperature has been observed over the last century, and it is predicted to further increase in the future. The effect of increased temperature on ecosystem carbon fluxes in a permanent temperate grassland was studied in a long-term (6 years) field experiment, using multiple temperature increments induced by IR lamps. Ecosystem respiration (R-eco) and net ecosystem exchange (NEE) were measured and modeled by a modified Lloyd and Taylor model including a soil moisture component for R-eco (average R2 of 0.78) and inclusion of a photosynthetic component based on temperature and radiation for NEE (R2 = 0.65). Modeled NEE values ranged between 2.3 and 5.3 kg CO2 m−2 year−1, depending on treatment. An increase of 2 or 3°C led to increased carbon losses, lowering the carbon storage potential by around 4 tonnes of C ha−1 year−1. The majority of significant NEE differences were found during night-time compared to daytime. This suggests that during daytime the increased respiration could be offset by an increase in photosynthetic uptake. This was also supported by differences in δ13C and δ18O, indicating prolonged increased photosynthetic activity associated with the higher temperature treatments. However, this increase in photosynthesis was insufficient to counteract the 24 h increase in respiration, explaining the higher CO2 emissions due to elevated temperature. This study was funded by AGRI-I (RSF 10/SC/716), the LOEWE-excellence program FACE2FACE, and the Walsh Fellowship program.

Cuniculus paca is considered locally threatened in some parts of its range mainly because of hunting pressure and habitat loss. The species is widely distributed in South and Central America. Agouti’s distribution in Brazil is broad, although there is no information on its occurrence in the Northeast region and in the western part of Rio Grande do Sul state. The species presents a marginal distribution in northeastern Uruguay. Here, we describe 16 new records of the species in the Pampa region, including the western part of Rio Grande do Sul state, Brazil and Uruguay, expanding the C. paca known distribution.

Carabus hungaricus is a typical steppic species declining throughout its range from Central Europe to Eastern Siberia, sharing the fate of the temperate grasslands, being listed in the Habitats Directive (Council Directive 92/43/EEC) (Annexes II and IV) and protected in most countries of occurrence. The populations are isolated, fragmented and even facing extinction. In the spring of 2014, we observed and photographed one female of Carabus hungaricus in “Coridorul Jiului” Natura 2000 site (ROSCI0045), in an area with sandy grasslands near Murta locality (Dolj County), this being the second currently confirmed station for Carabus hungaricus in Romania.

Sustainable rice production systems are key to food security. Diversified farming systems are essential for ecological intensification and environmental enhancement. Energy use efficiency is one of the main sustainability indicators in agroecosystems. Thus, an assessment of consumption and efficiency of energy in contrasting cropping systems can discriminate their management practices and components sustainability. The goal of this study was to evaluate the energy performance through energy return on investment (EROI) in four rice-based rotation systems that belong to a long-term experiment located in the Temperate Grassland Terrestrial Ecoregion, at the Atlantic side of South America. Rotations analyzed consisted in: a) continuous rice ( R c ); b) rice-soybean ( R − S ); c) rice-pasture for 1.5 years ( R − P S ); and, d) rice-pasture for 3.5 years ( R − P L ). The EROI estimations considered all the inputs and outputs of energy from cradle to farm gate. The greatest EROI was observed in R–S (7.2 M J M J − 1 ) and the lowest energy consumption in R − P L (10,607 M J ( h a y r ) − 1 ). The R − P L ’s EROI (6.7 M J M J − 1 ) was 6.5% and 8% higher than R c and R − P S EROI, respectively. Rotations without pastures produced 79% more energy compared with rotations including pastures. However, energy inputs of rice-pasture rotations were 40% lower than either R − S or R c . The EROI (without animal production) of R − P S , R–S and R c was 25%, 28% and 43% lower than the EROI of R − P L (10 M J M J − 1 ), respectively. For the analyzed South American ecoregion, EROI assessments of four business as usual rice production systems allowed to discriminate and hierarchize their sustainability and diversity.

Understanding future climate change requires accurate estimates of the impacts of atmospheric nitrogen (N) deposition, composed of both inorganic and organic compounds, on greenhouse gas (GHG) fluxes in grassland ecosystems. However, previous studies have focused on inorganic compounds and have not considered the potential effects of organic N sources. Here, we conducted a grassland experiment that included organic, inorganic N, and a mix of them at a ratio of 4:6, with two input rates, to study N inputs induced CO2, CH4, and N2O fluxes, as well as the potential abiotic and biotic mechanisms driving the fluxes. We found that N compositions significantly affected fluxes each of the three GHGs. Greater organic N decreased the impacts of N addition on CO2 and N2O emissions, caused primarily by low rates of increase in substrates (soil available N) for production of CO2 and N2O resulting from high ammonia volatilization rather than changes in microbial activity. Also, greater organic N slightly stimulated CH4 uptake. Nitrogen composition effects on CO2 emissions and CH4 uptake were independent of N input rates and measurement dates, but N2O emissions showed stronger responses to inorganic N under high N addition and in June. These results suggest that future studies should consider the source of N to improve our prediction of future climate impact of N deposition, and that management of N fertilization can help mitigate GHG emissions.

In nitrogen (N)-limited temperate regions, winter is an important period of N accumulation. The accumulated N is released during snowmelt and thawing, and the availability peaks in early spring. However, the early-spring dynamics of specific N forms (i.e., ammonium NH4+ and nitrate NO3−) in temperate grasslands are still not fully understood. Here, we added 15NH4+ and 15NO3− (equivalent to 150 mg 15N m−2) to the soils of a meadow steppe and a typical steppe in northern China immediately after snowmelt, then quantified the retention dynamics of 15NH4+ and 15NO3− in soils, microbes, and plants over the subsequent growing season. Approximately 70% of the added 15N tracers were initially retained within the soil−microbe−plant systems in both temperate grasslands. In early spring, much 15N was immobilized in soils and microbes, while little had been taken up by plants. During the subsequent growing season, approximately 45% of the 15N was rapidly lost by the soils and microbes, but plant 15N acquisition gradually increased. Although soils and plants retained similar levels of 15NH4+ and 15NO3− during the growing season, soil microbes retained more 15NH4+ than 15NO3−. Different plant taxa had distinct 15N acquisition capacities: perennial grasses and forbs accumulated the 15N tracers rapidly, while annuals did not. Perennial grasses were effective immobilizers of the 15NH4+, whereas forbs were effective immobilizers of the 15NO3−. These findings provided evidence of the substantial retention of early-spring N over the following growing season in temperate grasslands, regardless of the vegetation type and N form. However, it was clear that the dynamics of early-spring 15NH4+ and 15NO3− differed within the soil−microbe−plant systems.

‘It is a great travesty how a world grassland type that has nurtured the needs of humans for millenia has received so little appreciation, attention and protection’ (Carbutt et al. 2017, writing on temperate grasslands). The numerous calls for grassland conservation, in many parts of the world, and the now wide acceptance that grasslands have wide ecological and practical importance to humanity, as well as for sustaining native biota, constitute one of the best prospects for grassland insect conservation. At one level, those insects are then ‘passengers’ within the wider targets of conserving grassland biomes and resources – but are also recognised progressively as predominant functional components of sustaining those ecosystems, and that wider management of grasslands may be critical in their conservation.

Root turnover time is jointly predicted by climate factors and soil properties in global grasslands with different vegetation types. Pasture availability is directly related to the belowground dynamics of soil conditions on spatial scales. However, few studies have examined whether pasture availability could be a spatial indicator of grassland root turnover time on a global scale. In the present study, geographically weighted regression (GWR) modelling, coupled with the ordinary least squares (OLS) method, was used to develop an indicator of root turnover time in global grasslands based on pasture availability. The results revealed a significant relationship between pasture availability and root turnover time in global grasslands. Furthermore, this relationship may depend on the type of vegetation and could be affected by animal grazing (including buffaloes, cattle, horses, goats, pigs, and sheep). Based on regression modelling, significantly positive relationships were detected between pasture availability and root turnover time for temperate grassland and meadows (P