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Anthropogenic activities, species invasions, and ecological factors are driving rapid changes in rangeland ecosystems. For ensuring the richness and sustainability of plant species habitats, there is a pressing need for a reliable prediction model that can accurately forecast and map species distribution under varying ecological conditions. We aimed to compare the performance of three widely used machine learning methods: Multilayer perceptron (MLP), radial basis function (RBF), and support vector machine (SVM) in predicting the distribution of Festuca ovina in mountainous protected rangelands. We conducted our investigation by analyzing the distribution of F. ovina in 305 randomly selected plant sample plots. In each plot, we recorded 10 ecological variables. Three machine learning models were developed to predict the likelihood of F. ovina distribution. Our results demonstrated that the RBF model had a higher number of misclassifications (11 samples) compared to MLP and SVM models (10 samples), indicating that MLP and SVM models were more accurate for distribution modeling. Additionally, MLP showed a higher R‐squared value (0.87) compared to SVM (0.85), suggesting that MLP was the most accurate model for restoring degraded lands. Hence, we developed the Festuca ovina Distribution Model (FODM) using the MLP model. Sensitivity analyses revealed that soil texture, soil depth, electrical conductivity (EC), pH, and vegetation density significantly influenced F. ovina distribution, with respective sensitivity coefficients of 0.48, 0.47, 0.45, 0.41, and 0.41. Based on the finalized FODM, we designed an Environmental Decision Support System (EDSS) tool to assist rangeland managers in mapping F. ovina distribution. By applying the EDSS tool, we demonstrated its practicality in using the FODM for effective decision‐making and land management. The EDSS tool serves as a valuable resource for rangeland managers, enabling them to make informed decisions regarding F. ovina restoration and effectively use the predictive capabilities of the FODM in real‐world applications. [ABSTRACT FROM AUTHOR]

Vegetation recovery in severely disturbed alpine ecosystems can be accelerated through active restoration measures. This study evaluated the short‐term effects of two restoration treatments, planting of propagated native Salix (willow) shrubs in three different densities (1, 2.5, and 4 plants/m2) and seeding of the native grass Festuca ovina (sheep fescue), in a disturbed alpine heathland. We evaluated natural vegetation recovery (i.e. vegetation cover, vascular plant species richness, and Salix recruitment) in permanent plots, 5 years after the implementation of restoration measures. The results showed that both treatments had positive but different effects on vegetation recovery; Salix plantings (with densities ≥2.5 plants/m2) increased vascular plant species richness and recruitment of Salix seedlings, whereas seeding of F. ovina increased bottom and field layer cover. Our results also show the importance of soil conditions for vegetation recovery, as moister plots with a higher percentage of fine soil substrate had a higher vegetation cover and vascular plant species richness. This study shows that different restoration treatments can work complementary and also highlights the importance of considering different indicators of vegetation recovery when evaluating the effectiveness of restoration measures. [ABSTRACT FROM AUTHOR]

Reproductive and early‐acting life‐history traits are likely to be particularly important determinants of plant fitness under a changing climate. There have, however, been few robust tests of the evolution of these traits under chronic climate change in natural ecosystems. Such studies are urgently needed, to evaluate the contribution of evolutionary change to population persistence.Here, we examine climate‐driven evolutionary change in reproductive and early‐acting plant life‐history traits in the long‐lived perennial plant, Festuca ovina.We collected established plants of F. ovina from species‐rich calcareous grassland at the Buxton Climate Change Impacts Laboratory (BCCIL), after 17 years of in situ experimental drought treatment.P1 plants collected from drought‐treated and control (ambient climate) plots at BCCIL were used to create an open‐pollinated F1 progeny array, which was subsequently validated using microsatellite markers to establish a robust bi‐parental pedigree. We measured the timing of germination and seed mass in the F1 progeny, the P1 paternal contribution to F1 offspring (paternal reproductive success), and assessed the effects of flowering time on the mating system.F1 seed with ancestry in drought‐treated plots at BCCIL germinated significantly later than seed derived from individuals from control plots. P1 plants from the drought treatment flowered significantly earlier than those from the control plots in summer 2012, but not in 2013. Male reproductive success was also lower in P1 plants collected from drought plots than those from control plots. Furthermore, our pedigree revealed that mating among parents of the F1 progeny had been assortative with respect to flowering time.Synthesis. Our study shows that chronic drought treatment at Buxton Climate Change Impacts Laboratory has driven rapid evolutionary change in reproductive and early‐acting life‐history traits in Festuca ovina, and suggests that evolutionary differentiation may be reinforced through changes in flowering time that reduce the potential for gene flow. [ABSTRACT FROM AUTHOR]

Herbivory is one of the key drivers shaping plant community dynamics. Herbivores can strongly influence plant productivity directly through defoliation and the return of nutrients in the form of dung and urine, but also indirectly by reducing the abundance of neighbouring plants and inducing changes in soil processes. However, the relative importance of these processes is poorly understood. We, therefore, established a common garden experiment to study plant responses to defoliation, dung addition, moss cover, and the soil legacy of reindeer grazing. We used an arctic tundra grazed by reindeer as our study system, and Festuca ovina, a common grazing‐tolerant grass species as the model species. The soil legacy of reindeer grazing had the strongest effect on plants, and resulted in higher growth in soils originating from previously heavily‐grazed sites. Defoliation also had a strong effect and reduced shoot and root growth and nutrient uptake. Plants did not fully compensate for the tissue lost due to defoliation, even when nutrient availability was high. In contrast, defoliation enhanced plant nitrogen concentrations. Dung addition increased plant production, nitrogen concentrations and nutrient uptake, although the effect was fairly small. Mosses also had a positive effect on aboveground plant production as long as the plants were not defoliated. The presence of a thick moss layer reduced plant growth following defoliation. This study demonstrates that grasses, even though they suffer from defoliation, can tolerate high densities of herbivores when all aspects of herbivores on ecosystems are taken into account. Our results further show that the positive effect of herbivores on plant growth via changes in soil properties is essential for plants to cope with a high grazing pressure. The strong effect of the soil legacy of reindeer grazing reveals that herbivores can have long‐lasting effects on plant productivity and ecosystem functioning after grazing has ceased. [ABSTRACT FROM AUTHOR]

Questions (1) When alpine vegetation is actively restored by seeding, how is vegetation cover influenced by seeding treatments and soil conditions? (2) How does the cover of species differ when they are seeded in a mixture and how is their response influenced by soil conditions? (3) Do individual species perform better or worse in a mixture than when sown separately? Location Hjerkinn, Dovrefjell, Norway. Methods In a factorial, randomized field experiment, we recorded the percentage cover of Festuca ovina, Luzula multiflora subsp. frigida and Poa alpina seeded in four different soil types for 3 yr after seeding. We seeded the three species separately and in a mixture in organic topsoil, peat soil, mineral fine soil and mineral coarse soil. We also recorded seedling emergence in a greenhouse experiment, using the same seeding treatments. Results In the field experiment, vegetation cover established fastest when F. ovina was sown in monoculture, followed by the seed mixture. After 3 yr, mean cover of F. ovina was 1.4 times higher than mean P. alpina cover and more than three times higher than mean L. multiflora cover for single species treatments, and four ( P. alpina) and 15 ( L. multiflora) times higher when the species were seeded together. L. multiflora germinated slowly in the greenhouse experiment, which could partly explain its poor field performance. In the field experiment, establishment was faster in organic soils than mineral soils for all seeding treatments. The largest difference between F. ovina and L. multiflora performance in the mixture treatment was found in the organic soil types, where overall cover was larger than in the mineral soils. In the organic soils, F. ovina was slightly facilitated in the mixture treatment, while the opposite was found for L. multiflora. Conclusion When the restoration goal is to quickly establish a vegetation cover, seeding monocultures of rapidly establishing species may be more effective than seeding mixtures, even in alpine sites, where interspecific facilitation may prevail. [ABSTRACT FROM AUTHOR]

Studies of whether plant community structure and ecosystem properties depend on the genetic diversity of component populations have been largely restricted to species monocultures and have involved levels of genetic differentiation that do not necessarily correspond to that exhibited by neighboring mature individuals in the field. We established experimental communities of varying intraspecific genetic diversity, using genotypes of eight species propagated from clonal material of individuals derived from a small (lOO-m2) limestone grassland community, and tested whether genetic diversity (one, four, and eight genotypes per species) influenced community composition and annual aboveground productivity across communities of one, four, and eight species. Eight-species communities were represented by common grass, sedge, and forb species, and fourand one-species communities were represented by four graminoids and the dominant grass Festuca ovina, respectively. After three years of community development, there was a marginal increase of species diversity with increased genetic diversity in fourand eight-species communities, and genetic diversity altered the performance of genotypes in monospecific communities of F. ovina. However, shifts in composition from genetic diversity were not sufficient to alter patterns of community productivity. Neighborhood models describing pairwise interactions between species indicated that genetic diversity decreased the intensity of competition between species in four-species mixtures, thereby promoting competitive equivalency and enhancing species equitability. In F. ovina monocultures, neighborhood models revealed both synergistic and antagonistic interactions between genotypes that were reduced in intensity on more stressful shallow soils. Although the dependence of F. ovina genotype performance on neighborhood genetic composition did not influence total productivity, such dependence was sufficient to uncouple genotype performance in genetic mixtures and monocultures. Our results point to an important connection between local genetic diversity and species diversity in this species-rich ecosystem but suggest that such community-level dependence on genetic diversity may not feedback to ecosystem productivity. [ABSTRACT FROM AUTHOR]

Growth, dry matter partitioning and nitrogen capture were compared in two grasses of contrasted ecology, subjected to treatments involving pulses of nutrient enrichment of various durations supplied every 6 d over a period of 6 weeks. The potentially fast-growing Arrhenatherum elatius ssp. bulbosum (Willd.) Schubler and Martens was superior in rates of nitrogen capture and dry matter production when exposed to long ( > 10 h) nutrient pulses whereas the slow-growing species Festuca ovina L. enjoyed an advantage in treatments providing nutrient pulses of between 0.1 and 10 h duration. These results are consistent with differences in mechanisms of resource foraging predicted by the C-S-R model of plant strategies and related models. It is concluded that the lower rates of turnover of tissues and the capacity of roots to remain viable under chronic nutrient stress are important components of the ability of Festuca ovina to exploit brief pulses of mineral nutrient enrichment. The range in duration of the pulses advantageous to F. ovina corresponds to that which might be expected to arise from the death and recover of microbial populations in infertile soils. [ABSTRACT FROM AUTHOR]

The effectiveness of Festuca ovina and Poa pratensis as contour grass strips for erosion control was examined in a laboratory experiment for an erodible sandy loamsoil on 21, 25 and 29% slopes. No significant differences (P < 0.05) were observed in runoff between the plots with grass strips and bare soil but significant differences in soil loss were recorded. Both grasses reduced erosion in the early part of the simulated storms by ponding water behind the barrier, filtering sediment and causing deposition within the ponded area. The P. pratensis barrier was less rigid and became flattened under submergence in the later part of the storms. Runoff flowed over the grass strip forming rills on the slope below, which then cut back and undermined the barrier. These barriers resulted in as much soil loss as bare soil towards the end of the storms on all three slopes. The F. ovina was effective in controlling erosion on the 21% and 25% slopes but not on the 29% slope. [ABSTRACT FROM AUTHOR]