Pasture Abandonment Research Articles

Nutrient stocks and phosphorus fractions in mountain soils of Southern Ecuador after conversion of forest to pasture

Understanding pasture degradation processes is the key for sustainable land management in the tropical mountain rainforest region of the South Ecuadorian Andes. We estimated the stocks of total carbon and nutrients, microbial biomass and different P fractions along a gradient of land-uses that is typical of the eastern escarpment of the Cordillera Real i.e., old-growth evergreen lower montane forest, active pastures (17 and 50 years-old), abandoned pastures 10 and 20 years old with bracken fern or successional vegetation. Conversion of forest to pasture by slash-and-burn increased the stocks of SOC, TN, P and S in mineral topsoil of active pasture sites. Microbial growth in pasture soils was enhanced by improved availability of nutrients, C:N ratio, and increased soil pH. Up to 39 % of the total P in mineral soil was stored in the microbial biomass indicating its importance as a dynamic, easily available P reservoir at all sites. At a 17 years-old pasture the stock of NH4F extractable organic P, which is considered to be mineralisable in the short-term, was twice as high as in all other soils. The importance of the NaOH extractable organic P pool increased with pasture age. Pasture degradation was accelerated by a decline of this P stock, which is essential for the long-term P supply. Stocks of microbial biomass, total N and S had returned to forest levels 10 years after pasture abandonment; soil pH and total P 20 years after growth of successional bush vegetation. Only the C:N ratio increased above forest level indicating an ongoing loss of N after 20 years. Soil nutrient depletion and microbial biomass decline enforced the degradation of pastures on the investigated Cambisol sites.

Modern forest management and the decline of the Woodland Brown (Lopinga achine) in Central Europe

The Woodland Brown (Lopinga achine) is a characteristic flagship species for forests. Although it has experienced a dramatic decline, our knowledge concerning the reasons for the population loss is scarce. In this paper: (i) we analyze its habitat preferences on a regional scale in the Bavarian Alps; and (ii) we attempt to determine potential drivers of the decline on a national scale across Germany.Vegetation structure, microclimate and host-plant availability were the most crucial factors explaining habitat selection. Forests with a light canopy on south-facing slopes were the preferred woodland type in the study area. They had a medium-high and dense herbaceous layer rich in low-competitive sedges. Carex alba appeared to be the main host plant. Dense stands of C. alba are necessary to fulfill the eggs’ humidity requirements and to enable ease of access by the larvae. The preference for extraordinarily light forests on warm south-facing slopes most likely reflects a compensation for the cold mountain climate near the altitudinal range limit.Within Germany, L. achine populations have become extinct in regions with a mild climate, while most of the remaining colonies are restricted to areas with cold winters. However, the explanatory power of the model was very low. As the disappearance of the species coincides temporally with the abandonment of coppicing and wood pasture, we assume that the cessation of this management technique was the major driver of the range retraction. In most of the Central European habitats, long-term survival of L. achine strongly depends on suitable forest management.

Can re-establishment of cattle grazing restore bryophyte diversity in abandoned mesic semi-natural grasslands?

Changes of agricultural practices have led to decline of semi-natural habitats sustained by traditional animal husbandry in many European regions. The abandonment of semi-natural pastures leads to increase of vascular plant biomass and subsequent decline of weak competitors such as bryophytes. Re-establishing traditional animal husbandry may potentially restore biodiversity but the success of such measures remains insufficiently known. In this study, we asked if re-establishing cattle grazing on previously abandoned grasslands will restore their bryophyte communities. The effect of cattle grazing on bryophyte communities of mesic semi-natural grasslands was studied in south-western Finland in a comparison of (i) continuously grazed pastures, (ii) previously abandoned pastures where grazing was re-established during 1990s, and (iii) abandoned pastures, where grazing had ceased during late 1960s to early 1980s. The average cover, species richness, species density and species diversity of bryophytes were significantly higher in the continuously grazed than in the abandoned grasslands. Ordination analyses revealed clear differences also in community structure between the management classes. Re-established grasslands were ecologically heterogeneous and situated in between the continuously grazed and abandoned grasslands in all characteristics, indicating variable effect of the restoration measure. Seventeen bryophyte species were recognized as significant indicators of the three grassland classes, four of which could be used as indicators of valuable grassland habitats. Although there was variation in the consequences of re-introduction of grazing, the results give evidence of positive effect of grazing on regaining bryophyte diversity of abandoned grasslands.

Recovery of amphibian species richness and composition in a chronosequence of secondary forests, northeastern Costa Rica

In some tropical regions, following the abandonment of agriculture and pastures, secondary forests can recover plant species richness and forest structure (e.g. canopy cover, biomass); however, the importance of these secondary forests for fauna is not clear. Secondary forests can benefit fauna by providing suitable habitats, connecting forests fragments, and increasing gene flow. Previous studies of forest regeneration have showed different levels of amphibian recovery. In Puerto Rico, 1–5years old secondary forests achieved similar amphibian species richness and composition in comparison with old-growth forests, while in Brazil secondary forests from 14 to 19years of recovery only recovered 60% of the species of old-growth forests. We evaluated amphibian recovery in secondary forests in northeastern Costa Rica, by assessing amphibian recovery in 12 secondary forests that vary in age of recovery and in three old-growth forests using visual and acoustic surveys. Our sites varied in terms of their landscape (e.g. amount of surrounding forest) and forest characteristics (e.g. forest age, aboveground biomass, basal area, number of tree species, number of stems, leaf-litter depth), but there was no relationship between these characteristics and amphibian species richness or species composition. We found that amphibians are recovering rapidly in secondary forests in Costa Rica, and even young forests (10–16years) had similar species richness and composition in comparison with old-growth forests. These forests are providing suitable microhabitats conditions for amphibians. In addition, this study highlights the importance of landscape characteristics. The abundance of amphibian species sources (e.g. forest patches) and connections between forests appear to be helping the species colonize these sites. Worldwide, the area of secondary forests is increasing, and our results show that these habitats are suitable for a diversity of amphibian species, suggesting that these forests can help reduce amphibian population and species decline.

Drivers of floristic change in large cities – A case study of Frankfurt/Main (Germany)

The main aim of the study is to reconstruct diversity of established vascular plants between 1800 and 2000 in today's area of Frankfurt/Main (Germany, Hesse) – using historical literature, herbarium vouchers, and a recent landscape survey – and to interpret changes (extinctions and gains) in the light of land use changes (drivers). Species numbers declined from 1800 (1232 species; 926 indigenous–228 archaeophytes–78 neophytes) to 1900 (1200 species; 871–219–110), and 2000 (1107 species; 698–166–252). The most important drivers for the loss of species (319 spp.) are use of fertilizers and herbicides, abandonment of wood pastures, abandonment and melioration of wet grassland. Most species gained (193 spp.) were intentionally introduced as ornamentals. Among the neophytes naturalized after 1800, short-living plants adapted to dry open habitats dominate. Plants using the C4 carbon fixation pathway (C4-plants) are predominantly neophytes. Drivers for the loss of species are general changes in land use. Nature conservation slackened the loss of species in the last decades; today about 3% of the vascular plants are conservation dependent. Comparatively high rates of short-living plants adapted to dry open habitats and C4-plants among neophytes indicate a warming of the climate. We expect a rising number of garden escapes. Furthermore, the flora will become more dependent on conservation measures. Remnants of now obsolete forms of land use like low nutrient grassland shall be integrated into parks and urban open spaces.

Land-use change in a tropical mountain rainforest region of southern Ecuador affects soil microorganisms and nutrient cycling

Over the past decades, the tropical mountain rainforest of southern Ecuador has been threatened by conversion to cattle pastures. Frequently, these pastures are invaded by bracken fern and abandoned when bracken becomes dominant. Changes in land-use (forest–pasture–abandoned pasture) can affect soil microorganisms and their physiological responses with respect to soil carbon and nutrient cycling. In situ investigations on litter decomposition and soil respiration as well as biogeochemical characterization of the soil were carried out to identify the driving factors behind. The conversion of forest to pasture induced a pronounced increase in CO2–C effluxes to 12.2 Mg ha−1 a−1 which did not decrease after abandonment. Soil microbial activity and biomass showed a different pattern with lowest values at forest and abandoned pasture sites. With 3445 mg kg−1 (0–5 cm) microbial biomass carbon (MBC by CFE-method), the active pasture had a more than three times higher value than forest and abandoned pasture, which was among the highest in tropical pasture soils. A shift in the microbial community structure (phospholipid fatty acid, PLFA) was also induced by the establishment of pasture land; the relative abundance of fungi and Gram-negative bacteria increased. PLFA fingerprints of the forest organic layer were more similar to pasture than to forest mineral soil. Chemical properties (pH value, exchangeable cations) were the main factors influencing the respective microbial structure. Bracken-invasion resulted in a decrease in the quantity and quality of above- and belowground biomass. The lower organic substance and nutrient availability induced a significant decline in microbial biomass and activity. After pasture abandonment, these differences in soil microbial function were not accompanied by pronounced shifts in the community structure and in soil pH as was shown for the conversion to pasture. A disconnection between microbial structure and function was identified. Similar soil CO2–C effluxes between active and abandoned pasture sites might be explained by an underestimation of the effluxes from the active pasture site. All measurements were carried out between grass tussocks where fine-root density was about 2.6 times lower than below tussocks. Thus, lower proportions of root respiration were expected than below tussocks. Overall, soil microorganisms responded differently to changes in land-use from forest to pasture and from pasture to abandoned pasture resulting in pronounced changes of carbon and nutrient cycling and hence of ecosystem functioning.

Microbial communities on litter of managed and abandoned alpine pastureland

Degradation of litter strongly depends on its chemical composition, which in turn affects the associated microorganisms. In the alpine region, the abandonment of pastures leads to a rigorous change in the composition of the litter layer, shifting from grass to highly recalcitrant dwarf shrub litter, thus affecting the food web and decomposition processes. Three species belonging to different functional groups (grasses, herbs, dwarf shrubs) and indigenous on managed and/or abandoned alpine pastureland were selected for this study, the annual grass Dactylis glomerata, characteristic for managed sites, Trollius europaeus as representative of a herb common on both managed and abandoned areas, and Vaccinium vitis-idea as typical dwarf shrub arising on abandoned alpine pastures. Litter bags containing litter material from either one of the three plant types were incubated on the soil surface for 9 weeks. DNA was extracted from the substrate, amplified and analysed using PCR–DGGE. Fingerprinting analyses of bacterial and fungal communities showed that the microbiota attached to the litter differed considerably depending on the plant type. Nonetheless, specific bacterial bands were present in the fingerprinting patterns of all three litter types. Identifying these organisms applying the 16S rRNA clone libraries revealed the dominance of bacteria from the class Bacteroidetes, representing two thirds of all identified band positions.

Soil seed bank during succession at an abandoned pasture in the upper Paraná river-floodplain, Brazil

We evaluated density and species composition of the soil seed bank in active pasture and in secondary forest on a 10 year-old abandoned pasture to identify changes in density, richness, diversity and species composition during secondary succession of abandoned pastures. The implications of those changes for the forest recovery process were also considered. Soil samples were collected at Porto Rico island, state of Paraná, in 2007. The seedling emergence method was used. Data on active pasture collected in 1996, published by Campos and Souza (2003) were used for comparative analysis. No evidence was found of a pattern of changes in density of the soil seed bank during succession of abandoned pastures. We observed increases in richness and diversity, in the contribution of tree and shrub species and dominance of herb species for the seed bank during the first 10 years of abandonment of pastures in riparian forests. At the end of succession, the soil used as pasture can result in systems that are different from the original environment, due to seed bank impoverishment and presence of exotic species.

Development of spatially explicit emission scenario from land-use change and biomass burning for the input data of climate projection

In the preparatory phase of IPCC AR5 development, Representative Concentration Pathways (RCPs) have been constructed by Integrated Assessment Models (IAMs) groups as new forcing scenarios used for climate modeling and earth system modeling groups. In the process of RCP 6.0 scenario development, which has been conducted by the Asia-Pacific Integrated Model (AIM), we constructed a scenario of spatially explicit long-term aerosol emissions from biomass burning and net land-use change CO2 emissions in order to complement energy use and industrial emissions scenarios projected by socio-economic component of AIM.To estimate the emissions from biomass burning, we incorporate a vegetation fire component into the terrestrial biogeochemical process model VISIT (Vegetation Integrative SImulation Tool). For the net land-use change CO2 emission, we use gridded land-use change transition matrix data developed in the process of downscaling the RCP6.0 land use scenario for the evaluation of emission from deforestation (primary land and secondary land into cropland, pasture, and urban), and also the evaluation of regrowth absorption from abandonment of cropland and pasture. In this process, uncertainty of land emissions due to the effect of CO2 concentration and land-use scenario is examined, and reveals significant effect of CO2 fertilization effect on vegetation to the land emissions.

Root decomposition in grazed and abandoned dry Mediterranean dehesa and mesic mountain grasslands estimated by standard labelled roots

Because root turnover represents the major source for building up soil organic matter in ecosystems with high belowground allocation, like grasslands, sensitive analyses on root decomposition rates may contribute to point out the effect of grazing abandonment on soil C and N dynamics. The objective was to detect changes in root C and N mineralization due to pasture abandonment in Mediterranean dehesa mountain grasslands. Root decomposition was estimated by field incubation of 13C- and 15N-labelled wheat roots mixed with unlabelled soil over one year at 5cm depth in grazed and short-term excluded grasslands in three contrasting situations: (i) a Mediterranean dehesa, (ii) altimontane and (iii) subalpine sites. In addition, the long-term effect of grazing abandonment was estimated in a subalpine shrub encroached site. Overall, root decomposition rates decrease from Mediterranean to mountain sites. Moreover, on mountain sites, either grazing exclusion or shrub encroachment reduced 13C losses from root–soil bags in about four to seven percentage units; in contrast, such an effect was not detected in the Mediterranean grassland. The dynamics of 15N derived from root–soil bags was site-dependent without a clear pattern related to site climate or grazing abandonment. In general, the fate of mineralized root-N, leached or immobilized in the surrounding soil, seems to be related to soil variables such as the C:N ratio.

Asymmetric response to disturbance and recovery: Changes of soil permeability under forest–pasture–forest transitions

In the humid tropics, continuing high deforestation rates are seen alongside an increasing expansion of secondary forests. In order to understand and model the consequences of these dynamic land-use changes for regional water cycles, the response of soil hydraulic properties to forest disturbance and recovery has to be quantified. At a site in the Brazilian Amazônia, we annually monitored soil infiltrability and saturated hydraulic conductivity ( K s) at 12.5, 20 cm, and 50 cm soil depth after manual forest conversion to pasture (year zero to four after pasture establishment), and during secondary succession after pasture abandonment (year zero to seven after pasture abandonment). We evaluated the hydrological consequences of the detected changes by comparing the soil hydraulic properties with site-specific rainfall intensities and hydrometric observations. Within one year after grazing started, infiltrability and K s at 12.5 and 20 cm depth decreased by up to one order of magnitude to levels which are typical for 20-year-old pasture. In the three subsequent monitoring years, infiltrability and K s remained stable. Land use did not impact on subsoil permeability. Whereas infiltrability values are large enough to allow all rainwater to infiltrate even after the conversion, the sudden decline of near-surface K s is of hydrological relevance as perched water tables and overland flow occur more often on pastures than in forests at our study site. After pasture abandonment and during secondary succession, seven years of recovery did not suffice to significantly increase infiltrability and K s at 12.5 depth although a slight recovery is obvious. At 20 cm soil depth, we detected a positive linear increase within the seven-year time frame but annual means did not differ significantly. Although more than a doubling of infiltrability and K s is still required to achieve pre-disturbance levels, which will presumably take more than a decade, the observed slight increases of K s might already decrease the probability of perched water table generation and overland flow development well before complete recovery.

Short-term effects on sheep pastureland due to grazing abandonment in a Western Mediterranean island ecosystem: A multidisciplinary approach

Changes of pasture communities consequent to management practices resulting from land abandonment considerably affect the structure and function of the ecosystem. This study analyses the consequences of grazing abandonment in terms of plant and soil microbial diversity and fertility, on a Mediterranean upland sheep pasture, over a short period (five years). Grazing was experimentally excluded by fencing ten 10×10 m permanent plots within an area that had supported grazing until 2000, by 0.23 sheep ha −1. Plant and soil microbial communities and physicochemical parameters were monitored within the fenced and unfenced control plots, during three sampling times from 2000 (before the fencing) to 2005. Grazing cessation notably altered the floral composition, with an average dissimilarity of 96.7% between the vegetation communities, over five years. No significant change occurred in the control plots that were grazed throughout the sampling period. This work highlighted that, over a short term, the structural change in the specific plant composition affected only the grass species, confirming that grazing favours the small-sized species over the annual species. Further, it was evident that species groups of conservational and phytogeographic interest, like the endemic and Mediterranean-Atlantic species, tended to disappear with pasture abandonment and were substituted by more widespread species throughout the Mediterranean or even the world. Pasture abandonment was accompanied by an increase of soil pH and a decrease in soil organic matter and soil nitrogen. The microbial parameters recorded at three different sampling times revealed a substantial effect of the plant community, or the time of grazing abandonment, on soil microbial abundance and diversity. Considerable importance is given to the consequences of pasture abandonment on the conservation of plant and microbial diversity and on soil fertility.

Effects of land abandonment and changing habitat structure on avian assemblages in upland pastures of Bulgaria

SummaryOver the past half century, grassland birds in Europe have declined dramatically and in order to maintain and restore their populations it is critical to understand how habitat structures and quality within pastures affect birds. This study investigated the effects of habitat structure and pasture abandonment on grassland birds in IBA Ponor, western Bulgaria. Birds were sampled using the point count method at 143 randomly located circular plots and a total of 1,401 observations of birds from 31 species were recorded. The results showed that habitat complexity, management and landscape position influenced bird community structure and species occurrence within the upland pastures. Extensively grazed pastures supported higher structural complexity of vegetation cover and higher bird-species richness and diversity compared with abandoned ones. Moreover, bird species with a preference for grazed rather than abandoned pastures had higher conservation status and most were associated with shrub cover. To maintain high levels of avian diversity, habitat complexity within pastures should be maintained through extensive grazing, to ensure availability of scrub vegetation wherever possible. Finally, this study provided evidence that agri-environmental schemes should not be directly extrapolated from one country or region to another without been tested first, because within the same management, differences in habitat structural characteristics may exist due to the landscape and socio-economic characteristics of the region.

Active land use improves reindeer pastures: evidence from a patch choice experiment

AbstractThe industrialization of agriculture in western societies has often led to either intensified use or abandonment of farmland and open pastures, but experimental evidence on how the dynamics of farmed ecosystems affect space use by large herbivores is limited. We experimentally manipulated farmland patches with cutting and (early summer) low‐ and high‐intensity domestic sheep Ovis aries grazing according to traditional use in north Norway. After treatments, grazing reindeer Rangifer tarandus were exposed to the pastures the subsequent fall (2 months after treatments) and spring (11 months after treatments) as they typically do on their migratory route between summer and winter ranges. The experiment was conducted over 2 subsequent years. We predicted that sheep grazing on farmland during early summer may affect the critical fall and spring range conditions for reindeer either through negative (delayed competition) or positive (grazing facilitation) interactions. We found that the most marked effect of land use on the grazing pattern of reindeer was between no use (the control treatment) and all the other management options involving active land use. The grazing reindeer avoided the pastures no longer in use likely due to senescent plant material. There was a tendency that the lower intensity sheep grazing patches attracted more reindeer than the highest intensity use. These results highlight not only the general principle that large‐scale agricultural changes may affect large herbivores in natural ecosystems, but they also increase our understanding of grazing facilitation as a mechanism in large herbivore assemblages.

Impact of litter quality on mineralization processes in managed and abandoned pasture soils in Southern Ecuador

Tropical regions are currently undergoing remarkable rates of land use change accompanied by altered litter inputs to soil. In vast areas of Southern Ecuador forests are clear cut and converted for use as cattle pastures. Frequently these pasture sites are invaded by bracken fern, when bracken becomes dominant pasture productivity decreases and the sites are abandoned. In the present study implications of invasive bracken on soil biogeochemical properties were investigated. Soil samples (0–5 cm) were taken from an active pasture with Setaria sphacelata as predominant grass and from an abandoned pasture overgrown by bracken. Grass (C 4 plant) and bracken (C 3 plant) litter, differing in C:N ratio (33 and 77, respectively) and lignin content (Klason-lignin: 18% and 45%, respectively), were incubated in soils of their corresponding sites and vice versa for 28 days at 22 °C. Unamended microcosms containing only the respective soil or litter were taken as controls. During incubation the amount of CO 2 and its δ 13C-signature were determined at different time intervals. Additionally, the soil microbial community structure (PLFA-analysis) as well as the concentrations of KCl-extractable C and N were monitored. The comparison between the control soils of active and abandoned pasture sites showed that the massive displacement of Setaria-grass by bracken after pasture abandonment was characterized by decreased pH values accompanied by decreased amounts of readily available organic carbon and nitrogen, a lower microbial biomass and decreased activity as well as a higher relative abundance of actinomycetes. The δ 13C-signature of CO 2 indicated a preferential mineralization of grass-derived organic carbon in pasture control soils. In soils amended with grass litter the mineralization of soil organic matter was retarded (negative priming effect) and also a preferential utilization of easily available organic substances derived from the grass litter was evident. Compared to the other treatments, the pasture soil amended with grass litter showed an opposite shift in the microbial community structure towards a lower relative abundance of fungi. After addition of bracken litter to the abandoned pasture soil a positive priming effect seemed to be supported by an N limitation at the end of incubation. This was accompanied by an increase in the ratio of Gram-positive to Gram-negative bacterial PLFA marker. The differences in litter quality between grass and bracken are important triggers of changes in soil biogeochemical and soil microbial properties after land use conversion.

Diet-related composition of the gut microbiota of Lumbricus rubellus as revealed by a molecular fingerprinting technique and cloning

Interactions between earthworms and microorganisms are essential for the functioning of soil ecosystems as they affect organic matter degradation and nutrient cycling. This is also true for the alpine region, where socio-economic changes lead to the increasing abandonment of pastures, which in turn, causes a considerable shift in the diet of saprotrophic invertebrates and thus impacts food web and decomposition processes. To enhance our understanding of how this diet shift influences earthworms and associated microorganisms, we studied the gut content and cast microbiota of Lumbricus rubellus (Lumbricidae, Oligochaeta), a key macrodecomposer on alpine pastureland in the Central Alps. A feeding experiment with L. rubellus and three different food sources that represent the vegetation shift from an alpine pasture to an abandoned site was set up. Earthworms were collected in the field, transferred to a climate chamber and fed with cow manure, dwarf shrub or grass litter for six weeks. PCR-DGGE (Polymerase chain reaction-denaturing gradient gel electrophoresis) analysis of the DNA extracted from the substrates, the earthworms' gut contents and casts revealed that the gut and cast microbiota was strongly influenced by the food source ingested. Cloning of bacterial 16S rRNA gene fragments demonstrated that the intestinal content was dominated by Proteobacteria, especially from the Gamma-subclass, followed by members of the phyla Bacteroidetes, Actinobacteria and Firmicutes. In contrast, Actinobacteria were detected abundantly in all samples types when a cultivation approach was used. In conclusion, the gut microbiota of L. rubellus was shown to be substantially affected by the food source ingested, suggesting that this essential macrodecomposer is exposed to the diet shift resulting from a land-use change in the alpine area.

Molecular fingerprinting analysis of the gut microbiota of Cylindroiulus fulviceps (Diplopoda)

Summary Interactions between soil invertebrates and microorganisms are important for ecosystem functioning as they affect soil processes such as organic matter decomposition and nutrient cycling. This is also true for the alpine region, where the abandonment of pastures leads to a dramatic change in the diet of saprotrophic invertebrates, shifting from pre-digested ruminant dung to highly recalcitrant dwarf shrub litter, which in turn, affects food web and decomposition processes. To get a better understanding of the influence such a diet shift exerts on litter-feeding animals and associated microorganisms, we studied the gut microbiota of Cylindroiulus fulviceps (Julidae, Diplopoda), an essential macrodecomposer on abandoned alpine pastureland in the Central Alps. We investigated if the type of food ingested affects the composition of the gut microbiota of C. fulviceps or if its intestinal tract hosts an indigenous microbiota resilient to substrate changes. A feeding experiment was set up for which individuals were collected in the field, transferred to a climate chamber and fed with cow manure, grass litter or dwarf shrub litter for 6 weeks. DNA extracted from the substrate and the diplopods’ guts was amplified and analysed using PCR-DGGE. The fingerprinting analyses of bacterial, archaeal and fungal communities showed that the intestinal microbiota of C. fulviceps was only little influenced by the substrate ingested. Specific microorganisms that were robust against diet changes were found in the intestinal tracts. Identification of specific bacterial bands in the fingerprinting profiles revealed the dominance of Proteobacteria within the gut samples.

Komi reindeer herding: the effects of socialist and post-socialist change on mobility and land use

This paper contributes to the discussion concerning the way in which Soviet state policies have influenced the lives, social organization, economy and culture of a group of indigenous Komi reindeer herders of northern Russia: its main focus is to explain how these policies have changed the herders’ patterns of migration and land use. Extensive anthropological fieldwork—to determine current and past herding practices—was carried out and archives were thoroughly investigated to document land use changes in relation to state reindeer herding policies. It was found that compared with those of several decades ago, the migration routes are now much shorter, as the herders have abandoned large areas of winter pastures located in the southernmost part of their herding territory. This “abandonment” phenomenon is endemic amongst reindeer herders generally, throughout the Komi Republic. Whereas the reasons for the abandonment of winter pastures are diverse, they can be attributed mostly to the state sedentarization policy, which has modified the family structures of herders, and the continuing decreases in state subsidies that have changed the balance between state and private ownership of reindeer. Both these factors have greatly contributed to the herders’ dependence on visiting towns, where they now own flats, and on selling reindeer products, upon which they are increasingly reliant for financial security.

Effects of Historical and Likely Future Scenarios of Land Use on Above- and Belowground Vegetation Carbon Stocks of an Alpine Valley

Long-term trends including depopulation and shifts in agricultural policies and management have led to large-scale land-use changes throughout the European Alps which are likely to affect the size of carbon (C) stocks of the respective land-use types. This article analyzes landscape-scale changes of C-stocks present in the vegetation in relation to historical land use (1865), current land use (2003), and three contrasting scenarios of future land use (2020) in the Stubai Valley, Austria. Results show that more than 47% of the total valley area and more than 90% of the usable agricultural area have undergone a change in land use during the last approximately 140 years. Changes of land use were seen to peak between 1954 and 1973 and slow down there after. Phytomass and C-stocks in 1865 amounted to 63.1 Mg ha−1 and 30.8 Mg C ha−1, and increased until 2003 to 75.8 Mg ha−1 and 37.2 Mg C ha−1, respectively. Evaluations along an altitudinal gradient indicate the highest C gain to be in the sub-Alpine belt (more than doubling of the C-stock) due to the abandonment of pastures and hay meadows. All future scenarios project only a minor increase in phytomass (0.3–2.8 Mg ha−1) and C-stocks (0.2–1.4 Mg C ha−1) because major elements of the landscape (forests, rocks, screes) will be either largely unaffected or are unimportant in their spatial extent (built environment).

Spatial and temporal variability of soil saturated hydraulic conductivity in gradients of disturbance

Tropical montane rain forests are subject to both natural and anthropogenic disturbances, such as shallow landslides and forest-to-pasture conversion. Vegetation regrowth is rapid upon attaining hillslope stability and pasture abandonment, respectively, and apt to affect soil hydrology via changes in soil structure, a sensitive indicator of which is soil saturated hydraulic conductivity ( K s ). Our objective was to quantify the influence of these regionally widespread and important disturbances on K s and the subsequent recovery of K s , and to describe the resulting spatial patterns. In a 2 km 2 large research area in southern Ecuador, we used a mixed design- and model-based sampling strategy for measuring K s in situ at soil depths of 12.5, 20, and 50 cm ( n = 30–150/depth) under landslides of different ages (2 and 8 years), under actively grazed pasture, fallows following pasture abandonment (2–25 years of age), and under natural forest, and for elucidating its spatial patterns. Global means of soil permeability generally decrease with increasing soil depth. K s does not differ among landslides and in comparison to the natural forest, which suggests a marginal effect of the regional landslide activity on soil hydrology. In contrast, results from the human-induced disturbance regime show a permeability decrease of two orders of magnitude after forest conversion to pasture at shallow soil depths, and a slow regeneration after pasture abandonment that requires a recovery time of at least one decade. Disturbances affect the K s spatial structure, in particular the correlation length, in the topsoil. The largest differences in the covariance parameters, however, are found for the subsoil K s , where the spatial structure is independent of land cover. This case study suggests a rather disparate soil hydraulic response to regionally important disturbances. Cattle grazing strongly affects the spatial mean of K s , whereas landslides do not, and both the processes affect the spatial structure of K s in the topsoil.