Moist Grassland Research Articles

Prioritization of important plant areas for conservation of frailejones (Espeletiinae, Asteraceae) in the Northern Andes

AbstractThe tropical Andes region harbors areas that are highly significant for biodiversity at both global and local scales. However, despite the severe conservation threats that this region has to confront, conservation initiatives are limited, by funding and because of the need for more information to decide which areas are priorities for conservation. Identifying Important Plant Areas (IPAs) offers a valuable methodology for establishing conservation priorities, a particularly complex task in a mega-biodiverse region such as the northern Andean tropics. Due to its iconic recognition and conservation value, this study focused on the Espeletiinae subtribe (Asteraceae) as a model group; hence, the distribution data for 138 species was compiled from 5560 georeferenced records. Using the IPA methodology, we divided the study area, this is, the distribution area of the subtribe in the Andean tropics, into 220 Units of Analysis (UA) represented by 10 × 10 km plots. Refined species’ distribution areas, incorporating richness, threatened species, and ecosystem-based richness distributions, were analyzed using newly generated maps to evaluate the conservation value of each UA. Our analysis identified 176 UAs with some level of relevance using sub-criterion cA1 (with 59 species) and 51 UAs using sub-criterion cB (with 76 species). Integrating both criteria, we classified 11 UAs as high-priority, 62 as medium-priority, and 147 as low-priority, highlighting the IPAs that require focused conservation efforts. Two identified high-priority IPAs are located in Venezuela and nine in Colombia, predominantly associated with the Eastern Cordillera. These areas concentrate between 7 and 12 species. They are mainly linked to the páramo complexes of Colombia and the Sierra Nevada in Venezuela, primarily within Cool Temperate Moist Grassland ecosystems on mountains. Our results provide a spatial planning procedure and analytical tool for decision-makers to guide conservation management and actions across northern Andes.

Seed germination requirements of the rare Helosciadium repens (aka Apium repens) determine persistence of seeds in the soil seed bank.

The rare and threatened Heliosciadium repens grows in moist grasslands and has a distinct life cycle. Plants reproduce both clonally, although ramets tend to be short-lived, and sexually, with seeds that can form a persistent soil seed bank. The germination requirements of H. repens were investigated, yielding important information for its habitat management and conservation. We examined the soil seed bank in three populations and carried out germination experiments and embryo growth measurements with fresh seeds in laboratory, greenhouse and outdoor conditions. We also investigated the effects of storage and burial of seeds. H. repens formed a long-term persistent (>6 years) soil seed bank with very pronounced primary dormancy, but no secondary dormancy or dormancy cycles. Seeds can germinate throughout the growing season when temperatures are sufficiently high. Embryo growth and seed germination are triggered by light and, to a lesser extent, daily temperature fluctuations. Seeds of H. repens seem to have developed a unique germination syndrome with several strategies to remain dormant in the soil until optimal conditions are present for seedling establishment and survival. Both sexual reproduction and seed bank formation are crucial for the long-term survival of the populations.

Soil and Vegetation Characteristics of Grassland have a Greater Influence on the Abundance and Diversity of Earthworms than the Mowing Intensity in a Managed Nature Reserve

Effects of mowing on vegetation parameters have been well studied. However, less is known about mowing effects on soil fauna and if soil properties alter this. We investigated earthworm communities in a long-term experiment 14 years after its establishment in 5 dry, fresh and moist grassland plots located in the Natura 2000 site Lainzer Tiergarten near Vienna, Austria (238–402 m a.s.l., 48°10′ N, 16°12′ E). The grasslands were either mowed once a year or every second year, or not mowed since being established. Earthworms were assessed using the non-destructive octet electro-shocking method. Additionally, vegetation composition, soil conductivity, temperature and moisture were assessed. We found 13 earthworm species across all treatments, although their abundance was generally low with 6.1 ± 4.7 worms m−2. The total earthworm abundance and species diversity was higher in dry compared to fresh and moist grasslands but was not affected by mowing frequency. Endogeic earthworms (Aporrectodea caliginosa, Aporrectodea rosea) and epigeics (Lumbricus rubellus) were more tolerant to mowing than anecics (Lumbricus terrestris, Allolobophora longa). Since plant species richness was highest in annually mown grasslands and earthworm species richness was positively related to plant species numbers, we recommend regular, low-input management to promote above- and belowground biodiversity in these grasslands.

Environment and management jointly shape the spatial patterns of plant species diversity of moist grasslands in the mountains of Northeastern Yunnan

Grasslands account for about a quarter of the Earth’s land area and are one of the major terrestrial ecosystems, with significant ecological and economic value. The influence of environmental factors and management types on grassland biodiversity has garnered considerable attention. This study investigated how patterns of species richness are influenced by geographical distance, environmental gradients, and management type in the grasslands of northeastern Yunnan, China. We used structural equation modeling to disentangle the impacts of environment and management on phylogenetic community structure, and partial Mantel tests to estimate the roles of dispersal limitation and environmental filtering on taxonomic and phylogenetic beta diversity of three types of grasslands. Our results show that taxonomic alpha diversity increased in grazed grasslands and decreased in mowed grasslands, compared with protected grasslands. However, the phylogenetic structure of both grazed and mowed grassland communities was clustered, whereas that of protected communities was random. Moreover, both grazing and mowing significantly reduced the taxonomic and phylogenetic beta diversity of grasslands, with the lowest values observed in mowed grasslands. Both taxonomic and phylogenetic beta diversity were dominated by species turnover under different management types. The taxonomic and phylogenetic beta diversities of protected and grazed grasslands were simultaneously affected by environmental filtering and dispersal limitation, with the later playing a stronger role. In addition, mowing and related management measures had a stronger filtering effect on grassland community structure, as reflected by changes in community composition.

Evaluating the potential for reintroducing the endangered wild water buffalo (Bubalus arnee) in Kanha National Park, central India

Reintroducing megafauna to their historic range is an effective strategy to halt their extinctions and restore ecosystems. Wild water buffalo (Bubalus arnee) is an endangered megaherbivore that is lost from 95% of its range. About 90% of its global population (less than 4000) resides within India, in two isolated populations: northeast and central India. The central Indian population is on the verge of extinction and warrants urgent conservation interventions. We assess the potential and provide a strategy for reintroducing buffaloes in Kanha National Park, India. Habitat suitability using the global occurrence of buffalo revealed low‐lying grasslands with least human pressure found in Kanha (390 km2) to be suitable. Within this suitable range, we evaluated vegetation composition, forage biomass, and potential carrying capacity. Multidimensional ordination classified these suitable sites into moist and dry grassland clusters. Moist grasslands were found to better suit reintroduction due to lower grazing pressure, higher productivity, and availability of perennial water sources. Distinct matriarchal clades of swamp and river buffalo were observed. Within the river buffalo clade, Indian wild buffaloes formed a distinct cluster with close proximity between northeast and central Indian samples, suggesting northeast buffaloes could be sourced for a founding population in Kanha. Following IUCN guidelines, we discuss the reintroduction strategy that could sustain approximately 200 buffaloes in the area and subsequently expand to other suitable habitats in central India. If implemented as proposed, recovery of this lost ecosystem engineer will help to restore grasslands, and swamp habitats, as well as contribute to its global conservation efforts.

Global variations and drivers of nitrous oxide emissions from forests and grasslands

Nitrous oxide (N2O) emissions are highly variable due to the complex interaction of climatic and ecological factors. Here, we obtained in-situ annual N2O emission flux data from almost 180 peer-papers to evaluate the dominant drivers of N2O emissions from forests and unfertilized grasslands at a global scale. The average value of N2O emission fluxes from forest (1.389 kg Nha-1yr-1) is almost twice as large as that from grassland (0.675 kg Nha-1yr-1). Soil texture and climate are the primary drivers of global forest and grassland annual N2O emissions. However, the best predictors varied according to land use and region. Soil clay content was the best predictor for N2O emissions from forest soils, especially in moist or wet regions, while soil sand content predicted N2O emissions from dry or moist grasslands in temperate and tropical regions best. Air temperature was important for N2O emission from forest, while precipitation was more efficient in grassland. This study provides an overall understanding of the relationship between natural N2O emissions and climatic and environmental variables. Moreover, the identification of principle factors for different regions will reduce the uncertainty range of N2O flux estimates, and help to identify region specific climate change mitigation and adaptation strategies.

Decrease in species richness and diversity, and shrub encroachment in Cerrado grasslands: A 20 years study

AbstractQuestionThe Cerrado is a global biodiversity hotspot, highly threatened by changes in land use. Alterations in species composition and the colonization of Cerrado grasslands by woody species can lead to long‐term changes in these communities. In this study, we investigated changes over 20 years in three grassland areas, in terms of species richness and diversity and growth‐form cover, as well as the effects of shrub and grass encroachment on species richness.LocationCerrado Brazilian savanna, moist grassland and dry shrub grassland. Areas under low and high anthropogenic pressure.MethodsPlant species composition and cover were sampled on seven occasions between the years 2000 and 2020, in permanent line‐transects. We compared plant cover, richness, diversity and growth‐form cover between the periods for each area. Next, we developed mixed‐effect linear models to test whether species richness in grasslands at the latest sampling event was altered by species representing 70% of the species cover at this time.ResultsGrasslands located in areas under higher anthropogenic pressure presented reduced richness and diversity, and cover concentrated on a few species of shrubs and large tussock grasses. Moist grassland undergoing encroachment by the native shrub Trembleya parviflora had lost over 50% of its diversity since encroachment. In the same area, a shrub grassland undergoing encroachment by native shrub Raulinoreitzia tremula, three native grass species and one exotic grass presented significantly reduced species richness. The moist grassland in an area under low anthropogenic pressure showed a reordering of the species cover over time, but a decrease in species richness.ConclusionWe observed changes in plant richness, diversity, cover, composition and growth‐form cover over a period of 20 years in grassland communities. We found, however, different trajectories in the three grassland areas sampled, mainly due to the encroachment of a few species, leading to floristic homogenization in grasslands located in areas under high anthropogenic pressure.

Distribution of the greater naked-tailed armadillo Cabassous tatouay (Desmarest, 1804) in South America, with new records and species distribution modeling

ABSTRACT Cabassous tatouay occurs in moist forests, savannas, and grasslands of south, central, and northeastern Brazil, eastern Paraguay, northeastern Argentina, and Uruguay. Despite its wide distribution range, C. tatouay is scarcely recorded in some regions. This study aimed to: present new records of C. tatouay; compile the localities where the species was recorded according to published scientific accounts; and model its distribution range along South America. We present five new records of C. tatouay from Goiás and Minas Gerais states, Brazil. The review of published accounts resulted in 99 studies, which provided 279 occurrences of C. tatouay to Brazil, Argentina, Paraguay, and Uruguay. The great majority of records are from Brazil, mainly from the Atlantic Forest (119), Cerrado (52), and Pampas (49) biomes. Most records from the Cerrado are placed close to or in transition zones with the Atlantic Forest. Five records are within the Caatinga, but restricted to humid montane forest enclaves. The species distribution models indicate that C. tatouay is probably absent to Amazonia and Pantanal. The higher suitability for the species occurs in eastern Paraguay, northeastern Argentina, and south central Brazil, specifically in the Pampas, Atlantic Forest, and the southern part of the Cerrado.

Precipitation effects on nematode diversity and carbon footprint across grasslands.

Free-living nematodes are one of the most diverse metazoan taxa in terrestrial ecosystems and are critical to the global soil carbon (C) cycling through their role in organic matter decomposition. They are highly dependent on water availability for movement, feeding, and reproduction. Projected changes in precipitation across temporal and spatial scales will affect free-living nematodes and their contribution to C cycling with unforeseen consequences. We experimentally reduced and increased growing season precipitation for 2years in 120 field plots at arid, semiarid, and mesic grasslands and assessed precipitation controls on nematode genus diversity, community structure, and C footprint. Increasing annual precipitation reduced nematode diversity and evenness over time at all sites, but the mechanism behind these temporal responses differed for dry and moist grasslands. In arid and semiarid sites, there was a loss of drought-adapted rare taxa with increasing precipitation, whereas in mesic conditions increases in the population of predaceous taxa with increasing precipitation may have caused the observed reductions in dominant colonizer taxa and yielded the negative precipitation-diversity relationship. The effects of temporal changes in precipitation on all aspects of the nematode C footprint (respiration, production, and biomass C) were all dependent on the site (significant spatial×temporal precipitation interaction) and consistent with diversity responses at mesic, but not at arid and semiarid, grasslands. These results suggest that free-living nematode biodiversity and their C footprint will respond to climate change-driven shifts in water availability and that more frequent extreme wet years may accelerate decomposition and C turnover in semiarid and arid grasslands.

Predicted effects of simulated ambient warming and moisture on forage nutrient quality and community composition in Mongolian an arid grassland

Sustainable forage and livestock production in grazed grasslands are threatened by global climatic change. In this study, we examined how forage quality at the species and community levels in Mongolian drylands might be affected by warming and additional moisture. Four different treatments, a control, open-top chambers (OTCs) only, OTCs with heaters, and OTCs with additional watering, were set up in the field, and air and soil temperature and soil moisture were monitored. A vegetation survey was conducted and plants were harvested during summer, 1 and 2 years after experimental treatments were established. The harvested plant samples were separated into a dominant species (Stipa) or ‘other species’, and analysed to determine acid detergent fibre (ADF) and in vitro dry-matter digestibility (IVDMD). ADF was measured with the detergent method and the digestibility with the pepsin–cellulase assay. Overall, the warming treatments alone (OTC and OTC with heater) increased ADF 10% and 5% more than did the control at the species and community levels respectively, and decreased digestibility 12% and 11% below the control at the community level. Changes in plant nutritional value may have occurred as a result of changes in plant structure for some or all the plant species monitored, and an indirect effect of the shift in botanical species composition owing to warming. Unlike moist grassland, grass nutrition in arid grasslands was sensitive to treatments associated with the predicted effects of global warming as the results of changes in plant nutrition. It is therefore highly possible that Mongolian livestock production will be negatively affected as a result of ongoing global warming.

Estimating soil organic carbon changes in managed temperate moist grasslands with RothC.

Temperate grassland soils store significant amounts of carbon (C). Estimating how much livestock grazing and manuring can influence grassland soil organic carbon (SOC) is key to improve greenhouse gas grassland budgets. The Rothamsted Carbon (RothC) model, although originally developed and parameterized to model the turnover of organic C in arable topsoil, has been widely used, with varied success, to estimate SOC changes in grassland under different climates, soils, and management conditions. In this paper, we hypothesise that RothC-based SOC predictions in managed grasslands under temperate moist climatic conditions can be improved by incorporating small modifications to the model based on existing field data from diverse experimental locations in Europe. For this, we described and evaluated changes at the level of: (1) the soil water function of RothC, (2) entry pools accounting for the degradability of the exogenous organic matter (EOM) applied (e.g., ruminant excreta), (3) the month-on-month change in the quality of C inputs coming from plant residues (i.e above-, below-ground plant residue and rhizodeposits), and (4) the livestock trampling effect (i.e., poaching damage) as a common problem in areas with higher annual precipitation. In order to evaluate the potential utility of these changes, we performed a simple sensitivity analysis and tested the model predictions against averaged data from four grassland experiments in Europe. Our evaluation showed that the default model’s performance was 78% and whereas some of the modifications seemed to improve RothC SOC predictions (model performance of 95% and 86% for soil water function and plant residues, respectively), others did not lead to any/or almost any improvement (model performance of 80 and 46% for the change in the C input quality and livestock trampling, respectively). We concluded that, whereas adding more complexity to the RothC model by adding the livestock trampling would actually not improve the model, adding the modified soil water function and plant residue components, and at a lesser extent residues quality, could improve predictability of the RothC in managed grasslands under temperate moist climatic conditions.

Herbaceous-shrub species composition, diversity and soil attributes in moist grassland, shrub grassland and savanna in Central Brazil

The Cerrado biome comprises a mosaic of different vegetation types such as grasslands, savannas and forests. We studied soil properties and the herbaceous-shrub layer vegetation in moist grassland, shrub grassland and savanna. We assume that the moist grassland will present a distinct species composition from the other vegetation types, as waterlogging leads to changes in soil features that act as a filter of species that are adapted to this condition. The results showed that the soil in the moist grassland was distinct from the ones in savanna and shrub grassland. We found that the soil organic matter and the proportion of clay particles determined the variation in composition/cover and richness in the herbaceous-shrub layer in the three vegetation types. Higher organic matter content and smaller proportion of clay particles explained the larger distinction in richness and cover in moist grassland (lowest one) compared to shrub grassland and savanna sites. A total of 228 species in 47 families were sampled in the three vegetation types, and only five species were common to all three. The results revealed that, on a local scale, adjacent vegetation types of Cerrado with differences in soil organic matter and clay vary greatly in terms of growth forms, species composition and cover in the herbaceous-shrub layer. Understanding how herbaceous-shrub species richness and cover is related to soil nutrients, and texture heterogeneity in the mosaic of the vegetation types of the Cerrado may be useful in maintaining plant species structure and diversity.

Projected changes of carbon balance in mesic grassland ecosystems in response to warming and elevated CO2 using CMIP5 GCM results in the Central Great Plains, USA

Atmospheric CO2 increased in the 20th century and is expected to continue to do so in the 21st century, with resultant warming. Even so, the effects of these changes on the ecological systems, such as carbon sequestration in grassland ecosystems, are still poorly understood. To improve our understanding of the carbon balance, we developed a two-layer soil hydrology model for Terrestrial Ecosystem Model-Hydro Daily to simulate the carbon fluxes of moist grasslands more accurately. Using the outputs of two Representative Concentration Projection scenarios (RCP4.5 and 8.5) from five Coupled Model Inter-comparison Project Phase 5 climate models, we investigated if projected warming and rising atmospheric CO2 could stimulate net primary production (NPP), net ecosystem productivity (NEP), and ecosystem respiration of two highly productive grassland sites in the central Great Plains (USA) in the 21st century. Our study shows that elevated atmospheric CO2 has a fertilization effect in boosting NPP in grassland ecosystems, with a sensitivity of 0.53 gC m−2 yr−1 and 1.06 gC m−2 yr−1 under the RCP4.5 and RCP8.5 climate scenarios, respectively. Warming is more harmful to NPP in the grassland adapted to a warmer climate. Under the RCP4.5 scenario, both grassland sites likely experience a variable net ecosystem carbon exchange. However, the RCP8.5 scenario and accompanying severe warming would turn both grassland sites to net carbon sources by the end of the century, decreasing NEP by 0.97 gC m−2 yr−1 at the warmer site and by 0.96 gC m−2 yr−1 at the cooler site, driven by increased respiration and limited plant growth.

Montane seasonal wetlands: an inventory of its associated flora in Parque Estadual do Ibitipoca, southeast Brazil

Abstract The aim of the present study was to perform the floristic survey of the wetlands of the Parque Estadual do Ibitipoca (PEIB), comparing them regarding richness, floristic composition and life forms, based on monthly expeditions to collect vascular plants. Eighty-one (81) species were found in the moist grassland, most of them being endemic to Brazil and included in 55 genera and 21 families. The most representative families were Asteraceae (22 spp.), Melastomataceae (nine spp.), Xyridaceae (seven spp.), Poaceae and Orchidaceae (six spp. each), totalizing 62% of the sampled species. Twenty-seven (27) species were found in the seasonal pond, distributed in 23 genera and 11 families. Families with the highest specific richness were Poaceae (eight spp.), Cyperaceae and Asteraceae (five spp. each), totalizing 67% of the sampled species. There was a predominance of hemicryptophyte life form (nearly 43% of the moist grasslands and 63% of the seasonal pond) in both areas. The floristic analysis results showed great importance to conservation with 22% of species under some threatened category, 12 species endemics to Minas Gerais state and one new species of Cyperaceae. Furthermore, only five species occur in both wetland types (5.1% of the species richness).

Noblella thiuni sp. n., a new (singleton) species of minute terrestrial-breeding frog (Amphibia, Anura, Strabomantidae) from the montane forest of the Amazonian Andes of Puno, Peru.

We describe a new species of minute, terrestrial-breeding frog in the genus Noblella. We collected a single specimen in the leaf litter of primary montane forest (2,225 m a.s.l.) near Thiuni, in the Provice of Carabaya, Department of Puno, in the upper watershed of a tributary of the Inambari River of southern Peru, the same locality where we found the types of Psychrophrynella glauca Catenazzi & Ttito 2018. We placed the new species within Noblella on the basis of molecular data, minute size, and overall morphological resemblance with the type species N. peruviana and other species of Noblella, including having three phalanges on finger IV (as in N. coloma, N. heyeri, N. lynchi, N. madreselva, N. peruviana, and N. pygmaea), and terminal phalanges T-shaped and pointed. Noblella thiuni sp. n. is distinguished from all other species of Noblella by having ventral surfaces of legs bright red, and chest and belly copper reddish with a profusion of silvery spots. The new species further differs from known Peruvian species of Noblella by the combination of the following characters: tympanic membrane absent, eyelids lacking tubercles, dorsal skin finely shagreen, tarsal tubercles or folds absent, three phalanges on Finger IV, tips of digits not expanded, no circumferential grooves on digits, inguinal spots present. The new species has a snout–vent length of 11.0 mm in one adult or subadult male. Our new finding confirms the high levels of endemism and beta diversity of small, terrestrial-breeding frogs inhabiting the moss layers and leaf litter in the montane forests of the Amazonian slopes of the Andes and adjacent moist puna grasslands, and suggests much work remains to be done to properly document this diversity.

The March fly and the ant: the unusual pollination system of Eustegia minuta (Apocynaceae: Asclepiadoideae)

Pollination studies of South African Asclepiadeae (Apocynaceae: Asclepiadoideae) have mostly examined species in the moist summer-rainfall grasslands, with limited studies of the early-diverging groups occurring in the drier winter-rainfall habitats. This study examined the pollination and floral traits of Eustegia minuta, an unusual species endemic to the winter-rainfall Greater Cape Floristic Region and representing an early-diverging clade within the Asclepiadeae. Observations of floral visitors in Jonkershoek Nature Reserve showed that this species is visited primarily by a species of March fly, Bibio turneri (Bibionidae). These flies moved actively between plants and carried pollinaria on their mouthparts. In addition, an ant species, Camponotus vestitus (Formicidae), and a single honey bee Apis mellifera capensis (Apidae) individual carried pollinaria and may contribute to pollination. Bagging experiments confirmed that flowers require pollinators for reproduction. Flowers produced small amounts (1.2 µl per flower) of concentrated (32.5% sugar) nectar. Pollination success was low (14.5% of flowers were pollinated and 3.4% of flowers developed fruits). Pollen transfer efficiency (PTE) was 5.2%. The corolla reflectance was similar to that of green leaves, but the gynostegium exhibited a relatively bright human-white spectral curve. Floral scent comprised over 50 compounds, but was dominated by various aromatics along with 2,3-heptandione, (E)-4,8-dimethylnona-1,3,7-triene and several unidentified compounds. We conclude that E. minuta is pollinated primarily by the March fly B. turneri, although ants and possibly honey bees may make a lesser contribution. Pollination by bibionid flies has not previously been reported in asclepiads and is extremely uncommon amongst angiosperms.

Is the herb-shrub composition of veredas (Brazilian palm swamps) distinguishable?

Vereda (Brazilian palm swamp) is a poorly known savannic phytophysiognomy that occurs on moist soils with high herb-shrub floristic richness. This study aimed to document the herb-shrub species of veredas of the Estacao Ecologica Serra Geral do Tocantins - EESGTO, and compare this flora with other veredas in Brazil. Furthermore, we assessed the similarity of the herb-shrub flora of the studied veredas with that of inventories of other savannas and grasslands in order to evaluate whether veredas possess an exclusive flora. Ordination analysis was performed to understand the floristic relationship among these areas. We recorded 213 species, 105 genera and 49 families at EESGTO, including five new floral records for the Cerrado and 78 for the state of Tocantins. The floristic similarity among veredas at EESGTO and the other sites was low. For all sites, a total of 1,324 species were recorded, of which 342 were unique to veredas and 187 unique to moist grasslands (campos limpos umidos). After reviewing databases, 14.3 % of these species remained exclusive to veredas and moist grasslands. The ordination analysis indicated a gradient in floristic composition from wet to dry phytophysiognomies. In conclusion, we recognize a flora that distinguishes veredas from other Cerrado phytophysiognomies.

Germanium and rare earth elements in topsoil and soil-grown plants on different land use types in the mining area of Freiberg (Germany)

The total concentrations and chemical fractionation of Germanium (Ge) and selected rare earth elements (REEs) in top soils and soil-grown plants of different land use types (moist grassland, mesic grassland, arable land) were investigated in the post-mining area of Freiberg (Saxony, Germany). The study area covers approximately 1000km2 in the south of Central Saxony, and 138 samples from 46 sampling sites were examined. Ge and REEs in soils were partitioned by a sequential extraction procedure into mobile/exchangeable (Fraction 1), acid soluble (Fraction 2), bound to organic matter (Fraction 3), amorphous Fe/Mn-oxyhydroxides (Fraction 4), crystalline Fe/Mn-oxides (Fraction 5) and residual fractions (Fraction 6). Total concentrations of Ge and REEs in soil varied considerably ranging from 1.0μgg−1 to 4.3μgg−1 for Ge (mean 1.9μgg−1) and 97μgg−1 to 402μgg−1 (mean 168μgg−1) for total REE contents, accounting for 17% and 14% to the investigated light REEs La and Nd, respectively and 2.8% and 1.5% to the investigated heavy REEs Gd and Er, respectively. Elements in potentially plant available fractions represented 8% of total Ge and 30% of total REEs, respectively. Soils on moist grasslands characterized as acidic fluvisols and gleysols with high organic matter content contained significantly higher total concentrations of Ge and REEs and higher concentrations of Ge and REEs in the potentially plant available Fractions 1–3 compared to soils of mesic grassland and arable land. Grass species accumulated significantly higher concentrations of Ge than herb species. Highest concentrations of Ge were measured in plant species growing on moist grassland (Phalaris arundinacea: 449ngg−1), while there were no significant differences with regard to the concentrations of REEs in plants among the different land use types. The results of this study indicate that moist grasslands may act as sinks for Ge and REEs. In these soils high amounts of soil organic matter and low pH may foster the retention of labile forms, increasing the pool of Ge and REEs accessible for phytoextraction. However, the species-specific processes involved during the uptake of REEs need to be understood in order to optimize phytomining techniques.

Greenhouse gas emissions from fen soils used for forage production in northern Germany

Abstract. A large share of peatlands in northwestern Germany is drained for agricultural purposes, thereby emitting high amounts of greenhouse gases (GHGs). In order to quantify the climatic impact of fen soils in dairy farming systems of northern Germany, GHG exchange and forage yield were determined on four experimental sites which differed in terms of management and drainage intensity: (a) rewetted and unutilized grassland (UG), (b) intensive and wet grassland (GW), (c) intensive and moist grassland (GM) and (d) arable forage cropping (AR). Net ecosystem exchange (NEE) of CO2 and fluxes of CH4 and N2O were measured using closed manual chambers. CH4 fluxes were significantly affected by groundwater level (GWL) and soil temperature, whereas N2O fluxes showed a significant relation to the amount of nitrate in top soil. Annual balances of all three gases, as well as the global warming potential (GWP), were significantly correlated to mean annual GWL. A 2-year mean GWP, combined from CO2–C eq. of NEE, CH4 and N2O emissions, as well as C input (slurry) and C output (harvest), was 3.8, 11.7, 17.7 and 17.3 Mg CO2–C eq. ha−1 a−1 for sites UG, GW, GM and AR, respectively (standard error (SE) 2.8, 1.2, 1.8, 2.6). Yield-related emissions for the three agricultural sites were 201, 248 and 269 kg CO2–C eq. (GJ net energy lactation; NEL)−1 for sites GW, GM and AR, respectively (SE 17, 9, 19). The carbon footprint of agricultural commodities grown on fen soils depended on long-term drainage intensity rather than type of management, but management and climate strongly influenced interannual on-site variability. However, arable forage production revealed a high uncertainty of yield and therefore was an unsuitable land use option. Lowest yield-related GHG emissions were achieved by a three-cut system of productive grassland swards in combination with a high GWL (long-term mean ≤ 20 cm below the surface).

Flora vascular de uma área de campo úmido em Analândia, estado de São Paulo

Resumo A fitofisionomia de campo úmido integra-se ao bioma Cerrado quando próximo a nascentes e cursos d'água, e em áreas com lençol freático superficial. Devido às condições edáficas particulares que restringem e selecionam as espécies, esse ambiente apresenta uma flora bastante típica. O presente estudo objetivou listar as espécies de plantas vasculares registradas em área de campo úmido situada na Fazenda Pedra Vermelha, município de Analândia, estado de São Paulo, e comparar os resultados com outros de áreas campestres alagadas no Brasil. A área amostrada possui 5ha e está situada entre as coordenadas 22º7'50"-8'1"S e 47º46'40"-53"O, a 760-770 m de altitude. Foram realizados 18 expedições mensais de coleta, registrando-se 178 espécies em 121 gêneros e 62 famílias. Asteraceae (19 espécies), Cyperaceae (15), Poaceae (14), Melastomataceae (13), Xyridaceae e Eriocaulaceae (8) mostraram-se mais diversas. Uma provável espécie nova para Cyperaceae foi diagnosticada e sete espécies encontram-se listadas como em risco de extinção. A similaridade florística entre o campo úmido amostrado e as áreas usadas para comparação apresentou-se baixa. Os resultados obtidos comprovam uma riqueza florística significativa para o campo úmido da Fazenda Pedra Vermelha.