Grassland Species Research Articles

Adatok és kiegészítések Magyarország edényes flórájához

The paper presents 1593 current chorological data of 584 taxa (species, subspe­cies, varietas, hybrids) from Hungary, collected during the last few years. All of these connec­ted also to a total of 184 CEU quadrats. Among the species characteristic to the natural habi­tats, we high­lighted the records of several species protected in Hungary (Adoxa moschatelina, Althaea canna­bina, Cardamine parviflora, Centaurium pulchellum, Gagea pusilla, Orobanche reticulata, Potentilla patula, Rosa zagrabiensis, Spergula pentandra, Trifolium diffusum, Vale­rianella dentata, V. rimosa, Veronica officinalis, Viola collina and V. pumila). In the Northern part of Hungary, we observed the establishment of Cerastium dubium and Ranunculus peda­tus at several places along road­sides, which species have been known from the surrounding saline areas for a long time, but their appearance at roadsides is relatively new phenomenon. In addition, Aegilops cylindrica, Crypsis schoenoides, and Fumaria vaillantii subsp. vaillantii were found in one location – each species on roadsides. Along the railway tracks, we found disturbance-tolerant pioneers of rocky grasslands, open sandy and loess grasslands, e.g. many population of the native Androsace elon­gata, Anthemis ruthenica, Centaurea arenaria, Draba nemorosa, Erodium ciconium, Medicago monspeliaca, Microrrhinum minus, Saxifraga tridactylites and Vulpia myuros were found, as well as numerous ruderalia and the archae­ophyt such as Aegilops cylindrica. In addition to the more common species from the urban flora, we present some new data on the occurrence of the rarer Amaranthus blitum subsp. emarginatus, Chenopodium glaucum, Ch. murale, Ch. opulifolium, Ch. vulvaria and Euphorbia peplus. We have also listed some of the rarer field weeds and species that can establish in younger and older old-fields. Bromus secalinus has been found in several places in the north­eastern part of Hungary. We also observed Calepina irregularis, Centaurea solstitialis, Centau­rium pulchellum, Erysimum cheiranthoides, Filago lutescens, Fumaria officinalis subsp. of­ficinalis, Geranium dissectum, Misopates orontium, Myagrum perfoliatum, Reseda phyteuma, Sper­gularia salina and Veronica anagalloides populations. Erodium hoefftianum is a member of the natural flora, but is now found only in old-fields. We found some pasture weeds in re­gions where they are not common (e.g. Bupleurum tenuissimum, Cerastium dubium and Tri­folium striatum). The study also presents some species that are data deficient for taxonomic reasons, but not very rare ones (or we don’t know that). This group includes Arabis sagittata, Bolboschoenus glaucus, Bromus commutatus, B. racemosus, B. ramosus, Fumaria vaillantii subsp. schrammii, Ononis spi­nosiformis subsp. semihircina, Potentilla collina and Viola suavis “white morfotype”. We have drawn attention to the effect of ecological-botanical works on flora-influencing. We found An­themis ruthenica (species of sandy grasslands) in a moun­tain meadow, which is probably the result of seeds accidentally introduced by researchers. Finally, the paper provides data on the current distribution of hybrid taxa. A new individual of Betula ×rhombifolia was established in the Mátra Mts. We found some Euphorbia individuals that appeared to be a transitional form between E. esila and E. virgata (E. ×intercedens; Eu. esula subsp. saratoi). We also present some Verbascum and Viola hybrids. Hybrids were determined on a macromorphological basis.

Modeling the Distribution of the Rare and Red-Listed Halophytic Moss Species Entosthodon hungaricus Under Various Climate Change Scenarios in Serbia

Entosthodon hungaricus is a rare moss species of the salty grasslands in Serbia. It is threatened with extinction due to habitat destruction and loss, although it reproduces sexually. In this study, we tested different models predicting its distribution under several climate scenarios over the next 8 decades. All models tested indicated a reduction in range to varying extents. Due to the specific substrate type as well as the predicted loss owing to the climate change, shifting is not an option for the survival of this species; and, therefore, it deserves special attention for its conservation and management.

Root‐Borne Microbial Necromass—An Overlooked Source of Grassland Soil Organic Carbon

AbstractRoot‐borne microbial necromass carbon (MNC) is an under‐investigated contributor to soil organic carbon (SOC) in grasslands. Here we conduct a benchmark assessment of root‐borne MNC based on amino sugars in the fresh roots of 27 dominant species and mixed roots (including dead ones) of mixed species in Inner Mongolian grasslands. We find that mixed roots contain 9.1−62.4 mg g−1 MNC, which may contribute ∼10% of MNC in surface soils (0−10 cm) if all enters the soil without degradation. Root (and arbuscular mycorrhizal fungi; AMF) turnover rather than AMF biomass controls root‐borne MNC accumulation. Based on a microcosm decomposition experiment of mixed roots in model soils under optimal conditions (∼22°C; 60% of maximum water holding capacity), we further estimate that 43%−75% of root‐borne MNC remains after 2‐year decomposition, implying that root‐borne MNC is relatively stable. Hence, root‐borne MNC may be an overlooked potential source of soil MNC and SOC in grasslands.

Spatial Heterogeneity Affects the Spatial Distribution Patterns of Caragana tibetica Scrubs

Caragana tibetica is a common species in the shrub-encroached desert grasslands of Inner Mongolia, China. Studying its distribution and factors can improve our grasp of shrub-encroached grassland dynamics and aid in regional biodiversity conservation. This study examined eight C. tibetica communities using point pattern analysis to assess the spatial distribution pattern (SDP) and the influencing factors of C. tibetica scrubs. We also propose a new index, i.e., the degree of deviation index (DoDI), to quantify the SDP of scrubs. The results revealed the following: (1) The shrubland of C. tibetica in the study area showed aggregated distribution on the scale of 0–30 m. On the scale of 30–50 m, the degree of aggregation gradually weakened and random distribution appeared. (2) There was not a significant correlation between SDP and environmental factors; however, DoDI showed that habitat heterogeneity had a certain impact on C. tibetica in the study area. Our research indicates that spatial heterogeneity contributes to the SDP of shrub plants in the shrub-encroached grasslands of the Inner Mongolia Plateau, and the use of DoDI enhances the ability to quantify and isolate the role of spatial heterogeneity. This study helps to deepen the understanding of the mechanisms of shrub encroachment formation in grasslands.

Habitat management interventions for a specialist mid- successional grassland butterfly, the Lulworth Skipper

Evidence-based management is needed to reverse declines in insect abundance. The Lulworth Skipper Thymelicus acteon is a range-restricted and declining species in the UK and northern Europe associated with mid-successional grassland, which presents management challenges because interventions are necessary to prevent long-term habitat deterioration but can result in short-term reductions in quality. In addition, site management should be compatible for the focal species and for wider plant and insect diversity. We conducted factorial experimental management trials to understand effects of cutting and rotovation on the height and structure of vegetation containing the larval host plant Tor-grass Brachypodium rupestre. We monitored vegetation height, B. rupestre cover and plant diversity, and T. acteon larval presence over four years. Rotovation and cutting differed in their effects on habitat structure and larval occupancy relative to controls. Vegetation height and host plant cover, the most important components of habitat quality for T. acteon, were faster to recover to suitable levels on cut plots. However, larval occupancy increased more quickly on rotovated plots, where plant species diversity was also higher. Results suggest that due to initial negative impacts of interventions on T. acteon occupancy, low frequency or low-intensity management, such as managing sections of a site every three years, is advisable. Our results show that rotovation or cutting the sward can be suitable for mid-successional grassland species such as Lulworth Skipper on sites where grazing might be problematic. Rotational grazing or rotovation can maintain suitable conditions for habitat specialist insects requiring a range of different grassland conditions, serving wider conservation goals.

Correction to: Rapid root development in clay subsoils enhances the early growth of native grassland species

Correction to: Rapid root development in clay subsoils enhances the early growth of native grassland species

Historical and ongoing hybridisation in Southern South American grassland species

Natural hybridisation in plants can impact genetic and morphological diversity, including the emergence of better-adapted new populations and the potential extinction of some lineages involved in this intricate process. Under progressive global warming, species often need to migrate to newly suitable areas, which may be an additional challenge for species with low dispersal ability. Throughout the search for new environments, previously allopatric lineages can come into secondary contact and eventually hybridise if reproductive isolation is incomplete. Here, we focused on two taxa representing the natural herbaceous component of southern South American lowland grasslands. We aimed to evaluate the impact of contact zones and potential hybridisation on the evolutionary relationships and population dynamics. We used single nucleotide polymorphisms and morphological data of multiple individuals from allopatric and contact zones between taxa to shed light on hybridisation patterns and demographic scenarios. Our results indicated that the contact zones impact taxa’s genetic and morphological diversity, and each contact zone had different patterns of genetic diversity and morphology, constituting stable populations that potentially reflect hybridisation events occurring at distinct evolutionary times.

Overview of plant species translocations in Luxembourg

In Luxembourg, 34 % of native plants and archaeophytes are considered threatened or regionally extinct. Species translocations have been implemented in Luxembourg for more than 25 years as a conservation strategy to counteract biodiversity loss. In this overview, we have compiled data on conservation actions implemented between 1997 and 2023. The information collected includes the translocation locations, the plant taxa targeted, the methods used, and the monitoring conducted. For a subset of translocations, we have also included data on the survival of planted juveniles. Examples of translocations from various habitat types were also presented to illustrate different approaches. We found that 585 translocations involving 99 taxa from 26 families were initiated by four main institutions in Luxembourg. The conservation actions mainly targeted Endangered and Critically Endangered, but also Least Concern species. Translocations mainly took place in open land habitats, particularly in grasslands and arable land, with a higher density in the southwestern part of the country. 39 % of the translocations took place in national nature reserves whereas 21 % were in areas without any legal protection status. Planting young plants was the preferred method rather than sowing seeds. In 89 % of the translocations, monitoring was conducted by recording survival of the plants, while natural recruitment of new individuals was rarely recorded. 68 % of the translocations were judged successful by the practitioners, mostly based on transplant survival. Detailed data for the subset of 31 grassland species showed that the survival rate of about half of the species considered successful varied between 25 and 71 %. Translocations are essential for the long-term conservation of plant species, but protection and adaptive management of translocation sites are also essential. Translocations conform to national and European priorities for increasing habitat restorations to counteract species decline. To improve conservation outcomes, actions such as translocations need to be consistently documented, monitoring standardized, and experience needs to be shared among stakeholders.

Lambs Grazing With Adult Ewes Prefer Forbs With High-Nutrient Content in Native Grasslands Dominated by Leymus chinensis and Stipa grandis.

Grazing livestock in grasslands face the challenge of obtaining sufficient nutrition due to uneven distribution of plant species and fluctuating vegetation productivity and nutrient levels. In northern China, Leymus chinensis and Stipa grandis are the dominant perennial species in native grasslands, but they provide limited nutrition compared to forbs with higher crude protein (CP) content. While dietary ingredients can affect the nutritional intake of grazing livestock, the influence of different grazing strategies on dietary selection remains unclear. In this study, three sheep grazing strategies (lambs alone, mixed lambs and ewes, and ewes alone) were used to explore dietary selection. We investigated the influence of vegetation characteristic (above-ground biomass production, height, and species diversity) and foraging behavior (feed intake, organic matter digestibility, and daily grazing time) on the mechanisms of dietary selection (taxonomic family richness and composition). Forage consumption across the grazing strategies revealed that species from Poaceae, Rosaceae, and Cyperaceae families were frequently consumed. Both ewes and lambs in the mixed-grazing strategy preferentially consumed forbs with diverse species composition (Jacob's D > 0), which contained higher CP than those available in the overall vegetation (p < 0.05). In addition, dietary richness was significantly (p < 0.05) influenced by vegetation species diversity except for animals in the lambs alone strategy. Compared to lambs in mixed-grazing, lambs alone had both greater daily grazing time and consumption of grass with lower digestibility (p < 0.05). Our study is the first to demonstrate that lambs can develop a similar dietary selection and behavioral pattern when grazing with adult ewes in temperate grasslands. Our study indicates that the conservation of species diversity in native grasslands is critically beneficial to livestock nutrition.

Exposure of Bromus hordeaceus to fossil- and plant-based micro- and nanoplastics: Impacts and plant-plastic interactions vary depending on polymer type and growth phase

Plastic pollution, especially pollution by micro- and nanoplastics, is now considered a potential threat to all ecosystems, including terrestrial ecosystems such as grassland habitats. This study investigated the impacts of micro- and nano-sized plastics on Bromus hordeaceus, a common grass species in European grasslands. The micro and nanoparticles were fossil-based polyethylene (PE) or plant-based polybutylene adipate terephthalate (PBAT), and these two plastics were used at two different concentrations. Here, we report data on plant development and plastic-plant interactions from two different experiments, (1) an in vitro experiment to test seed germination and establishment and (2) a soil experiment to test plant development and plastic-plant interactions specifically investigated as a form of perforation. Results from the in vitro experiment indicate that while seed germination success was unaffected by plastic type, the presence of all plastic particle types acted as a stimulant, increasing the total length of radicles and sprouts of germinated seeds. Conversely, results from the soil experiment showed that the growth of Bromus hordeaceus was negatively affected by the presence of microPBAT in the soil during the pot assay.Microscopic analysis confirmed that seed and plant structures interacted with all plastic particles via adsorption or perforation. This study demonstrates for the first time the ability of roots to penetrate plastics, especially microPBAT particles. Overall, our study concludes that both fossil-based and plant-based micro- and nano-plastics can influence plant growth, with effects varying based on plastic type, concentration, and plant growth phase. Further research is crucial to fully understand the intricate interactions between microplastics, soil properties, and plant development.

Remotely Sensed Variables Predict Grassland Diversity Better at Scales Below 1,000 km as Opposed to Abiotic Variables That Predict It Better at Larger Scales

AbstractGlobal spatial patterns of vascular plant diversity have been mapped at coarse grain based on climate‐dominated environment–diversity relationships and, where possible, at finer grain using remote sensing. However, for grasslands with their small plant sizes, the limited availability of vegetation plot data has caused large uncertainties in fine‐grained mapping of species diversity. Here we used vegetation survey data from 1,609 field sites (&gt;4,000 plots of 1 m2), remotely sensed data (ecosystem productivity and phenology, habitat heterogeneity, functional traits and spectral diversity), and abiotic data (water‐ and energy‐related, characterizing climate‐dominated environment) together with machine learning and spatial autoregressive models to predict and map grassland species richness per 100 m2 across the Mongolian Plateau at 500 m resolution. Combining all variables yielded a predictive accuracy of 69% compared with 64% using remotely sensed variables or 65% using abiotic variables alone. Among remotely sensed variables, functional traits showed the highest predictive power (55%) in species richness estimation, followed by productivity and phenology (48%), spectral diversity (48%) and habitat heterogeneity (48%). When considering spatial autocorrelation, remotely sensed variables explained 52% and abiotic variables explained 41%. Moreover, Remotely sensed variables provided better prediction at smaller grain size (&lt;∼1,000 km), while water‐ and energy‐dominated macro‐environment variables were the most important drivers and dominated the effects of remotely sensed variables on diversity patterns at macro‐scale (&gt;∼1,000 km). These findings indicate that while remotely sensed vegetation characteristics and climate‐dominated macro‐environment provide similar predictions for mapping grassland plant species richness, they offer complementary explanations across broad spatial scales.

Rapid root development in clay subsoils enhances the early growth of native grassland species

Rapid root development in clay subsoils enhances the early growth of native grassland species

Spatial and Temporal Patterns of Grassland Species Diversity and Their Driving Factors in the Three Rivers Headwater Region of China from 2000 to 2021

Biodiversity loss will lead to a serious decline for ecosystem services, which will ultimately affect human well-being and survival. Monitoring the spatial and temporal dynamics of grassland biodiversity is essential for its conservation and sustainable development. This study integrated ground monitoring data, Landsat remote sensing, and environmental variables in the Three Rivers Headwater Region (TRHR) from 2000 to 2021. We established a reliable model for estimating grassland species diversity, analyzed the spatial and temporal patterns, trends of change, and the driving factors of changes in grassland species diversity over the past 22 years. Among models based on diverse variable selection and machine learning methods, the random forest (RF) combined stepwise regression (STEP) model was found to be the optimal model for estimating grassland species diversity in this study, which had an R2 of 0.44 and an RMSE of 2.56 n/m2 on the test set. The spatial distribution of species diversity showed a pattern of abundance in the southeast and scarcity in the northwest. Trend analysis revealed that species diversity was increasing in 80.46% of the area, whereas 16.59% of the area exhibited a decreasing trend. The analysis of driving factors indicated that the changes in species diversity were driven by both climate change and human activities over the past 22 years in the study area, of which temperature was the most significant driving factor. This study effectively monitors grassland species diversity on a large scale, thereby supporting biodiversity monitoring and grassland resource management.

Tetracycline but not sulfamethazine inhibits early root growth of wild grassland species, while seed germination is hardly affected by either antibiotic

Seed germination and early growth of grassland species might be influenced by veterinary antibiotics that are extensively released into agricultural habitats. Therefore, we tested impacts of the commonly used antibiotics tetracycline and sulfamethazine, single and in mixture, on seed germination and seedling root growth of six typical species of temperate European grasslands (Carum carvi, Centaurea jacea, Galium mollugo, Plantago lanceolata, Silene latifolia, Dactylis glomerata). In standardised germination experiments, we assessed three germination variables (germination percentage, mean germination time, synchrony of germination) and one post-germination variable (seedling root length) under different environmentally realistic antibiotic concentrations (0.1, 1, 10 mg l−1 and a water control). While the germination variables were only irregularly and weakly affected by both antibiotics, seedling root length was strongly reduced by tetracycline, but not by sulfamethazine. Among the test species, D. glomerata was most sensitive to tetracycline with the average root length reduced up to 81 % in the 10 mg l−1 treatment. Its germination behaviour, however, was almost insensitive to the two antibiotics. Mixture effects were only shown in relation to the germination of single species, where the binary mixture produced effects but not the two single antibiotics or, conversely, effects of single antibiotics were lost in the mixture. These findings highlight the potential threat of plant regeneration from seed by veterinary antibiotics, particularly affecting early root growth and potentially influencing plant population growth in natural habitats.

Major distribution shifts are projected for key rangeland grasses under a high-emission scenario in East Africa at the end of the 21st century

Grassland landscapes are important ecosystems in East Africa, providing habitat and grazing grounds for wildlife and livestock and supporting pastoralism, an essential part of the agricultural sector. Since future grassland availability directly affects the future mobility needs of pastoralists and wildlife, we aim to model changes in the distribution of key grassland species under climate change. Here we combine a global and regional climate model with a machine learning-based species distribution model to understand the impact of regional climate change on different key grass species. The application of a dynamical downscaling step allows us to capture the fine-scale effects of the region’s complex climate, its variability and future changes. We show that the co-occurrence of the analysed grass species is reduced in large parts of eastern Africa, and particularly in the Turkana region, under the high-emission RCP8.5 scenario for the last 30 years of the 21st century. Our results suggest that future climate change will alter the natural resource base, with potentially negative impacts on pastoralism and wildlife in East Africa.

Context dependence of grassland plant response to arbuscular mycorrhizal fungi: The influence of plant successional status and soil resources

Abstract Many of the disturbance‐sensitive, late successional plant species in grasslands respond to arbuscular mycorrhizal (AM) fungi more positively via growth and establishment than plants that readily establish in disturbed areas (i.e. early successional species). Inoculation with AM fungi can therefore aid the establishment of late successional species in disturbed areas. If the differential benefit of AM fungi to late versus early successional plants is context‐dependent, however, this advantage could be diminished in high phosphorus (P) post‐agricultural soils or in future climates with altered precipitation. In this greenhouse experiment, we tested if late successional plant species are less plastic in their reliance on AM fungi than early successional plants by growing 17 plant species of different successional status (9 early and 8 late successional) in full factorial combinations of inoculated or uninoculated with AM fungi, with ambient or high P levels, and with low or high levels of water. AM fungi positively affected the biomass of the 17 grassland plant species, but across all environments, late successional plant species generally responded more positively to AM fungi than early successional plants species. AM fungal growth promotion and change in below‐ground biomass allocation was generally diminished with P fertilizer across all plant species, and while there was significant variation among plant species in the sensitivity of AM fungal responsiveness to P fertilization, this differential sensitivity was not predicted by plant successional status. The role of AM fungi in plant growth promotion was not generally altered by variation in watering, however late successional plant species allocated a greater proportion of their biomass below‐ground in response to AM fungi in low versus high water conditions. Synthesis. Overall greater responsiveness to arbuscular mycorrhizal (AM) fungi by late successional species is consistent with an important role of AM fungi in plant succession, even while AM fungi are less impactful overall in high P soils. However, the increase in responsiveness of below‐ground allocation of late successional species to AM fungi in low water conditions suggests that successional dynamics may be more dependent on AM fungi in future climates that feature greater propensity for drought.

A Small-Sample Classification Strategy for Extracting Fractional Cover of Native Grass Species and Noxious Weeds in the Alpine Grasslands.

The fractional cover of native grass species (NGS) and noxious weeds (NW) provides a more comprehensive understanding of grassland health in the alpine grasslands. However, coverage extraction of NGS and NW from satellite hyperspectral imagery can be challenging due to the small spectral and spatial feature difference, insufficient training samples, and the lack of effective fractional cover extraction methods. In this research, firstly, a feature optimization method is proposed to optimize the difference feature between NGS and NW. Secondly, a spectral-spatial constrained re-clustering training sample extension method (SSCTSE) is proposed to increase the number of training samples. Thirdly, a composite three-kernel SVM method (CTK-SVM) is developed to produce fractional cover maps of NGS and NW. The experimental results show that (1) the feature optimization method is effective in preserving the spectral and spatial difference features while eliminating invalid features; (2) the SSCTSE algorithm is capable of significantly increasing the number of training samples; (3) the fractional cover maps of NGS and NW are produced with the CTK-SVM method with overall accuracies of approximately 65%, and the RMSEs of NGS and NW are approximately 16% and 11%, respectively. The results provide a foundation for the fractional cover extraction of different grass species in alpine grasslands based on satellite hyperspectral imagery.

Vegetation Growth and Physiological Adaptation of Pioneer Plants on Mobile Sand Dunes

The Hunshandake Sandy Land is one of the largest sandy areas in China and the closest source of sand dust to the Beijing and Tianjing areas. Sand fixation by vegetation is considered the most efficient strategy for sand control and sustainable development, so clarifying the vegetation coverage and plant adaptation characteristics in the Hunshandake Sandy Land is helpful in guiding restoration and improving local sustainability. Here, we investigated the vegetation growth on the mobile sand dunes in the Hunshandake Sandy Land and specified the photosynthesis and stomatal characteristics of the pioneer plants for sand fixation. The vegetation survey showed that the windward slopes of the mobile sand dunes had far lower plant coverage (6.3%) and plant biodiversity (two species m−2) than the leeward ones (41.0% and eight species m−2, respectively). Elymus sibiricus L. and Agriophyllum squarrosum (L.) Moq. were the only two sand-fixing pioneer plants that grew on both the windward and leeward slopes of the mobile sand dunes and had higher plant heights, greater abundance, and more biomass than other plants. Physiological measurements revealed that Elymus sibiricus L. and Agriophyllum squarrosum (L.) Moq. also had higher photosynthetic rates, transpiration rates, and water use efficiency. In addition, the stomata density (151–197 number mm−2), length (18–29 μm), and area index (13–19%) of these two pioneer species were smaller than those of the common grassland species in Inner Mongolia, suggesting that they were better adapted to the dry habitat of the mobile sand dunes. These findings not only help in understanding the adaptive strategies of pioneer plants on mobile sand dunes, but also provide practical guidance for sand dune restoration and the sustainable development of local areas. Pioneer sand-fixing plant species that are well adapted to sand dunes can be used for sowing or aerial seeding in sand fixation during ecosystem restoration.

Rhizosphere priming and effects on mobilization and immobilization of multiple soil nutrients

Living roots and their rhizodeposition play a vital role in mediating soil organic carbon (SOC) decomposition and nutrient mobilization. It is virtually unknown how the rhizosphere effects on soil nutrient mobilization are connected with the rhizosphere priming on SOC decomposition. Here we investigated the rhizosphere effects of six grassland species (four grasses and two legumes) on soil nutrient mobilization and SOC decomposition with and without nitrogen (N) fertilization in a 95-day pot experiment. Plant nutrient acquisition, soil extractable nutrients, and net nutrient mobilization or immobilization were determined to evaluate the rhizosphere effect on soil nutrient dynamics. Primed SOC decomposition was measured as the difference in soil-derived CO2–C between planted and unplanted treatments. Without N fertilization, all species consistently increased net phosphorus (P), sodium (Na), iron (Fe), and copper (Cu) mobilization and most species increased net N, sulfur (S), calcium (Ca), and zinc (Zn) mobilization and net potassium (K), magnesium (Mg), and manganese (Mn) immobilization compared to the unplanted soil. These results suggest that grassland species could induce both positive and negative rhizosphere effects on soil nutrient mobilization with different magnitude. With N fertilization, plant-induced net N mobilization increased, while plant-induced net P and S mobilization decreased. Further, plant biomass, plant N, P, and S acquisition, and plant-induced net N, P, and S mobilization (i.e., net nutrient mobilization in excess of the unplanted control), were positively correlated with primed SOC decomposition across six species, indicating that the mobilization of organically bound nutrients (N, P, and S) was connected with the rhizosphere priming on SOC decomposition. In contrast, plant-induced net nutrient mobilization of base cations and micronutrients was not related to primed SOC decomposition. Overall, our results demonstrate that a substantial portion of nutrient availability stems from rhizosphere processes and is plant species-specific, and that nutrient release of N, P and S are closely connected with rhizosphere priming on SOC decomposition.

The Individual Division of Food Hoarding in Autumn Brandt's Voles (Lasiopodomys brandtii).

Brandt's voles (Lasiopodomys brandtii), one of the main non-hibernating rodent species in the typical grassland of Inner Mongolia, live in groups and have the behavioral habit of hoarding food in underground warehouses in autumn to prepare for the winter food shortage ahead. The division of labor and cooperation are typical behavior patterns of gregarious mammals, but it is unclear whether Brandt's voles exercise a division of labor in food hoarding before overwintering. To explore the division of food hoarding in Brandt's voles during the autumn period, three treatments, namely added food, added food + competition, and control, were set up with three replicates. An infrared camera was positioned to observe and record the behavior of Brandt's voles under different treatments. Next, behavioral experiments regarding food-hoarding division were performed on individuals. The results showed that (1) Brandt's voles had two types of hoarding behavior, namely high food hoarding and low food hoarding, but not all individuals displayed hoarding behavior. (2) In all treatments, feeding behavior, which was the most important type of behavior, accounted for the highest proportion of all behaviors. (3) There was no significant difference in body weight and sex between high- and low-food-hoarding individuals of Brandt's voles, and there was no significant difference between high- and low-food-hoarding individuals in other divisions of labor either. (4) There was no significant difference in inquiry ability between high- and low-food-hoarding groups, but there was a significant difference in spatial memory. High-food-hoarding individuals had greater spatial memory. In summary, Brandt's voles had two types of hoarding behavior: high food hoarding and low food hoarding. Furthermore, high-food-hoarding individuals had greater spatial memory.