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Questions: Livestock management in rangelands depends on the production of plant biomass. Biomass production is driven by the temporal and spatial variability in precipitation, but our understanding of how precipitation variability mediates grazing effects on biomass production is still fragmented. Along a 600-km precipitation gradient we extracted biomass data to ask the questions: (a) what are the effects of grazing intensity on biomass production; (b) does grazing intensity interact with plant species richness to affect biomass production; and (c) how do plant functional groups respond to grazing and precipitation?. Location: Mongolia. Methods: Biomass was sampled along 15 grazing intensity transects within the precipitation gradient over two consecutive years. We modeled spatial variability in above-ground plant biomass using mixed-effects models. Normalized difference vegetation index (NDVI) data were combined with field-sampled biomass data to correct for inter-annual precipitation variation. The effects of species richness were modeled with respect to possible interactions with grazing intensity, and the composition of plant functional groups was modeled with respect to possible interactions between grazing intensity and precipitation. Results: Biomass was negatively correlated with grazing intensity and this effect increased as precipitation increased. Biomass was positively correlated with species richness in both years, but the strength of this effect and the interaction between species richness and grazing intensity differed between 2014 and 2015 in line with highly variable precipitation between both years. The plant functional groups grasses, sedges, legumes, wormwood and forbs had contrasting responses to grazing and precipitation. Conclusion: Biomass production in drylands is more vulnerable to changes in precipitation variability and grazing intensities in relatively moist and productive rangelands than in dry and unproductive ones. Future rangeland management needs to address potentially increasing precipitation variability in order to promote desired forage plants, and to preserve the positive effects of biodiversity for biomass production.

In this study, we investigate the performance of machine learning classification approaches and different remotely sensed data sources for identifying and mapping three types of grassland communities found in the Mongolian Steppe region (Artemisia, Caragana and grass dominated steppes). The Mongolian steppe is intensively used as pasture and provides the economic basis for approximately 1 million herders. The grassland types differ in their forage values, which is why a spatially-explicit estimation of their occurrence is of high importance. We compared different sensors, classifiers, and training-sample strategies to identify the most effective approaches for mapping these communities. Ten datasets were used: Landsat 8 OLI (30 m), pan-sharpened Landsat 8 (15 m), Landsat 8 Surface Reflectance (30 m), Sentinel 2 (10 m), Sentinel 2 (20 m), Worldview 3 (0.5 m and 1.2 m), integrated Landsat 8 and Sentinel 2 (30 m), temporal Landsat 8, and temporal Sentinel 2. The two foremost classifiers at producing high accuracy of land cover classification, SVM and RF, were applied with the same training datasets. The training samples were collected in a manner so that they could be used for different spatial resolutions (i.e., ranging from 0.5 to 30 m) with the least effect from mixed training samples and spatial autocorrelation. The results of this study indicate that remote sensing is a viable method for the identification of different grassland communities in the Mongolian Steppe region.

There are still major gaps in our understanding of rangeland degradation. Assessing the interactions between climate and grazing effects could help to explain what unifies and separates rangelands, and may therefore promote a more sustainable management of livestock. We studied 15 local land-use transects along a 600 km long climatic gradient in Central Asia to test the hypothesis that grazing effects differ between relatively moist equilibrium (EQ) and dry non-equilibrium (NEQ) rangeland systems. We analysed plant community composition, species diversity and indicator species for different grazing intensities. We found pronounced differences in community composition along our climate gradient, revealed climate-related grazing effects on richness, responses of Simpson's diversity, and also found different grazing indicator species along the larger transect. We conclude that in NEQ rangelands, grazing effects are limited to sacrifice zones and environmental filtering dominates vegetation composition. With increasing precipitation, resource availability gains in importance leading to more complex communities dominated by grazing-tolerant species under EQ dynamics. Hints for xerophytization in the transition zone between EQ and NEQ highlight the vulnerability of rangelands that temporally shift from one state to the other. This calls for extra care in the management of livestock numbers in these transition areas.

The Munkhkhairkhan mountain area is a unique highland ecosystem with a diverse regional alpine flora. This mountain habitat is located at the overlap of different floristic regions: on its western side KazakhstanâTuran flora is dominating, and on the eastern side East Asian flora is observed. It is known that the whole area has a large number of endemics and rare plant species, because of its specific, harsh habitat conditions. Therefore, the flora of different habitats in the Munkhkhairkhan mountain needs to be investigated and properly protected. Munkhkhairkhan National Park has been founded in 2006, and our survey concentrated on the protected area as well as the surrounding areas of the mountains. All recorded species in this study were based on the collected voucher specimens. Conservation status for remarkable species was also reviewed based on the literature. As a result, we recorded 40 families, 150 genera, and 267 species of vascular plants, including four endemic and 34 subendemic species and 15 species' new distribution notes. Around the Munkhkhairkhan mountain, 16 very rare, 21 rare, eight endangered, and two near threatened species are growing, indicating the high conservation value of this area and the necessity for research. Keywords: Conservation status, Mongolia, Munkhkhairkhan national park, Vascular flora