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Highlights •55% of the Upper Paraná Basin (UPRB) has undergone land use and cover changes (LUCC). •Cropland areas have shown the most significant increases in the UPRB. •Grassland areas were massively converted to croplands between 1985 and 2015. •Grassland areas moved towards the north, invading Cerrado and Amazon regions. •Economic drivers were primarily responsible for these LUCC scenarios. Abstract In this study, we show the complexity associated with the recent land cover changes by elucidating the paths of 30 years of changes in the Upper Paraná River Basin (UPRB), a region severely impacted by agricultural activity, one of the areas with the highest density in the production of hydroelectricity, biofuels and food in the world. In this sense, a post-classification comparison approach based on Landsat images was used to identify detailed ‘from-to’ paths behind those land cover changes. The most expressive changes were the expansion of Cropland and Forest areas and the reduction in savannas, with a net change of 17.9%, 4.1%, and −16.9% of the UPRB area, respectively. Cropland areas showed an expressive increase between 1985 and 2015, rising from 249,439 km2 (27.7%) to 412,909 km2 (45.9%). Forest areas increased from 149,389 km2 to 185,839 km2 in the period. Notably, for this class, an intense spatial dynamic of losses (7.5%) and gains (11.6%) took place between 1985 and 2015. This behavior is related to the disappearance of native vegetation fragments in some sub-basins, as well as to afforestation, reforestation, and/or forest restoration in others. The Cerrado (a typical tropical savanna in South America), the most impacted natural biome of the Basin, decreased from 21.9% of the UPRB in 1985 (196,746 km2) to only about 5% of the whole UPRB area in 2015. Grassland areas, mostly used for livestock, decreased from 271,827 km2 (30.2%) to 229,007 km2 (25.5%). This net decrease was associated with a reduction of 160,830 km2 (17.8%) and the appearance of 118,010 km2 (13.2%) in new areas, previously occupied by tropical savannas in 1985. In conclusion, economic factors were the main drivers for land cover changes, especially agriculture and livestock activities, besides forestry and hydroelectric energy production. In addition, Grassland areas that predominated on the left banks of the UPRB in 1985 retreated with the advance of Cropland areas, mainly due to the expansion of sugarcane for ethanol production, a biofuel widely used in Brazil. In turn, pasture areas migrated to the right bank and occupied a significant part of the Cerrado. Finally, our results demonstrate that the transition dynamics among land cover classes can involve complex political-economical mechanisms that are not always captured by remote sensing.

Wood-pastures are threatened anthropogenic biotopes that provide habitat for an extensive group of species. Here we studied the effect of management, grazing intensity, time since abandonment, historical land-use intensity, soil properties and stand conditions on communities of saprotrophic fungi in wood-pastures in Central Finland. We found that the proportion of broadleaved trees and soil pH are the major drivers in the communities of saprotrophic fungi in these boreal wood-pastures. In addition, tree species richness, soil moisture, historical land-use intensity and time since abandonment affected the communities of saprotrophic fungi. Current management or grazing intensity did not have a clear effect on saprotrophic fungal species richness, although dung-inhabiting fungal species richness was highest at intermediate to high grazing intensity. Obviously, there were many more dung-inhabiting fungal species on grazed than on abandoned sites. Our study highlights the conservation value of wood-pastures as hotspots of saprotrophic fungi. peerReviewed

International audience; In the western Algerian steppe, the public authorities have carried out actions aimed at rural development (agricultural development programs) and combating desertification (grazing reserves) to counter the significant and rapid loss of vegetation cover of pastures by overgrazing, and the consequent impacts on local livelihoods. In the Rogassa area, these actions have impacted land tenure and the ancestral and collective way of land use and access. These changes have caused transformations in lifestyle and pasture management. This research aims to characterize how such changes are affecting local pastoralists and what their perceptions are about them. A selective sampling of 150 agropastoral households was carried out by interviewing their heads, analyzing socioeconomic, land tenure and government perception variables. Most agropastoralists access land under tribal tenure, conditioned by local social structures. Pastures are prevailingly perceived by pastoralists as insufficient, and the perception of grazing reserves is largely negative. Pastoralists are worried about land degradation and declining grazing lands, and are looking for solutions and alternatives. However, state interventions have been uncoordinated and have not considered their customary land rights. The generalized awareness of environmental deterioration points to the need for better communication and intervention strategies to be developed by authorities in the future that involve the inhabitants of these lands.

Grassland biodiversity, including traditional rural biotopes maintained by traditional agricultural practices, has become threatened worldwide. Road verges have been suggested to be complementary or compensatory habitats for species inhabiting grasslands. Species co-occurrence patterns linked with species traits can be used to separate between the different mechanisms (stochasticity, environmental filtering, biotic interactions) behind community structure. Here, we study species co-occurrence networks and underlying mechanisms of ground beetle species (Carabidae) in three different managed grassland types (meadows, pastures, road verges, n = 12 in each type) in Central Finland. We aimed to find out whether road verges can be considered as compensatory to traditional rural biotopes (meadows and pastures). We found that stochasticity explained over 90% of the pairwise co-occurrences, and the non-random co-occurrences were best explained by environmental filtering, regardless of the grassland type. However, the identities and traits of the species showing non-random co-occurrences differed among the habitat types. Thus, environmental factors behind environmental filtering differ among the habitat types and are related to the site-specific characteristics and variation therein. This poses challenges to habitat management since the species’ response to management action may depend on the site-specific characteristics. Although road verges are not fully compensatory to meadows and pastures, the high similarity of species richness and the high level of shared species suggest that for carabids road verges may be corridors connecting the sparse network of the remaining traditional rural biotopes.

Peatland restoration via rewetting aims to recover biological communities and biogeochemical processes typical to pristine peatlands. While rewetting promotes recovery of C accumulation favorable for climate mitigation, it also promotes methane (CH4) emissions. The potential for exceptionally high emissions after rewetting has been measured for Central European peatland sites previously grazed by cattle. We addressed the hypothesis that these exceptionally high CH4 emissions result from the previous land use. We analyzed the effects of cattle dung application to peat soils in a short- (2 weeks), a medium- (1 year) and a long-term (grazing) approach. We measured the CH4 production potentials, determined the numbers of methanogens by mcrA qPCR, and analyzed the methanogen community by mcrA T-RFLP-cloning-sequencing. Dung application significantly increased the CH4 production potential in the short- and the medium-term approach and non-significantly at the cattle-grazed site. The number of methanogens correlated with the CH4 production in the short- and the long-term approach. At all three time horizons, we found a shift in methanogen community due to dung application and a transfer of rumen methanogen sequences (Methanobrevibacter spp.) to the peatland soil that seemed related to increased CH4 production potential. Our findings indicate that cattle grazing of drained peatlands changes their methanogenic microbial community, may introduce rumen-associated methanogens and leads to increased CH4 production. Consequently, rewetting of previously cattle-grazed peatlands has the potential to lead to increased CH4 emissions. Careful consideration of land use history is crucial for successful climate mitigation with peatland rewetting. peerReviewed

Traditional rural biotopes such as wood pastures are species rich habitats which have been created by extensive agriculture. In all European countries both the quality and quantity of traditional rural biotopes have drastically decreased during the past century because of increasing farming intensity. This decline is causing a threat to many species, but very little is known about the conservation ecology of fungi living in wood pastures. Considering vascular plants, it is known that sites with long management history have higher species richness compared to abandoned sites. It is also known that species richness is highest with intermediate grazing intensity. In this study I investigated if there is a difference in fungal species richness between presently grazed and presently ungrazed sites. I also investigated the effect of grazing history on fungal species richness and community assembly. In addition, I studied the effect of current grazing intensity on fungal species richness. All my study sites were broadleaved wood pastures in Central Finland. I studied 12 sites of which 6 were presently grazed by domestic animals and 6 were presently not, but had been grazed in the past. Grazing history of the study sites varied between 40-205 years, and considering sites which were presently ungrazed, the time after abandonment varied between 5-40 years. I focused on the agarics, boletoids, ramarioid fungi, Gasteromycetes, Pezizomycetes, and stipitate polypores. I conducted both sample plot surveys and time constrained surveys on each study site and repeated the surveys three times. Overall, I found 313 fungi species in this study. I found out that presently grazed sites do not have more fungal species than presently ungrazed sites. Instead, my results suggest that fungal species richness increases with grazing history duration and sites with long grazing history have a similar community structure even if they are presently ungrazed. I also suggest that with intermediate grazing intensity species richness is the greatest. I conclude that it is very important to know detailed management history when prioritizing management for sites. Moreover, targeting for optimal grazing intensity for sites may be important.

Moose ( L.) browsing was studied in young Scots pine ( L.) stands mixed with deciduous trees in high-density winter ranges. The proportional use of twig biomass decreased as the availability increased. The total as well as proportional biomass consumption were higher on the moist than on the dry type of forest. The per tree consumption of pine was higher on the moist type, where the availability of pine was lower. Deciduous trees were more consumed on the moist type, where their availability was relatively high. The consumption of pine saplings increased as the availability of birch increased. Pine stem breakages were most numerous when birch occurred as overgrowth above pine and at high birch densities. The availability of other deciduous tree species did not correlate with browsing intensity of Scots pine. Moose browsing had seriously inhibited the development of Scots pines in 6% of the stands, over 60% of available biomass having been removed. Rowan and aspen were commonly over-browsed and their height growth was inhibited, which occurred rarely by birch. There was no difference in the proportion of young stands in forest areas with high and low moose density. A high proportion of peatland forests was found to indicate relatively good feeding habitats in the high-density areas.Alces alcesPinus sylvestris