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Although we understand the ecological processes eliciting changes in plant community composition during secondary succession, we do not understand whether co-occurring changes in plant detritus shape saprotrophic microbial communities in soil. In this study, we investigated soil microbial composition and function across an old-field chronosequence ranging from 16 to 86 years following agricultural abandonment, as well as three forests representing potential late-successional ecosystems. Fungal and bacterial community composition was quantified from ribosomal DNA, and insight into the functional potential of the microbial community to decay plant litter was gained from shotgun metagenomics and extracellular enzyme assays. Accumulation of soil organic matter across the chronosequence exerted a positive and significant effect on fungal phylogenetic β-diversity and the activity of extracellular enzymes with lignocellulolytic activity. In addition, the increasing abundance of lignin-rich C 4 grasses was positively related to the composition of fungal genes with lignocellulolytic function, thereby linking plant community composition, litter biochemistry, and microbial community function. However, edaphic properties were the primary agent shaping bacterial communities, as bacterial β-diversity and variation in functional gene composition displayed a significant and positive relationship to soil pH across the chronosequence. The late-successional forests were compositionally distinct from the oldest old fields, indicating that substantial changes occur in soil microbial communities as old fields give way to forests. Taken together, our observations demonstrate that plants govern the turnover of soil fungal communities and functional characteristics during secondary succession, due to the continual input of detritus and differences in litter biochemistry among plant species.

Land use change is the result of interactions between processes operating at different scales. Simulation models at regional to global scales are often incapable of including locally determined processes of land use change. This paper introduces a modeling approach that integrates demand-driven changes in land area with locally determined conversion processes. The model is illustrated with an application for European land use. Interactions between changing demands for agricultural land and vegetation processes leading to the re-growth of (semi-) natural vegetation on abandoned farmland are explicitly addressed. Succession of natural vegetation is simulated based on the spatial variation in biophysical and management related conditions, while the dynamics of the agricultural area are determined by a global multi-sector model. The results allow an exploration of the future dynamics of European land use and landscapes. The model approach is similarly suitable for other regions and processes where large scale processes interact with local dynamics.

Understanding constraints to ecological restoration on former agricultural land has become increasingly important due to agricultural land degradation in the developed world, and growing evidence for enduring agricultural legacies that limit native species recovery. In particular, the removal of native plant biomass and subsequent disturbance of soil properties through farming activities can alter soil ecosystem processes. Planting of native plant species is a common approach to restoring native vegetation on agricultural land and is assumed to benefit soil ecosystem processes, but the degree to which altered soil chemical processes recover is poorly documented. We investigated recovery of soil chemical properties after restoration in semiarid Western Australia, hypothesizing that elevated nutrient concentrations would gradually decline post planting, but available phosphorus (P) concentrations would remain higher than reference conditions. We used a space-for-time substitution approach, comparing 10 planted old field plots with matched fallow cropland and reference woodlands. Sampling on planted old fields and reference woodland plots was stratified into open patches and under tree canopy to account for consistent differences between these areas. The most prominent legacy of cropping was significantly and substantially higher concentrations of soil available P in fallow croplands and restored old fields compared with reference woodlands. Soil mineral nitrogen (N) concentrations were elevated in fallow croplands compared to open patches in reference woodlands (ammonium and nitrate) and under the tree canopy (ammonium). However, in restored old fields, mineral N concentrations were similar to woodland sites, providing evidence for amelioration over time. No significant differences in nutrient concentrations under tree canopies compared with open patches had developed in the planted old fields, despite a distinction between open patches and he under ttree canopy in reference woodlands for total N. We conclude that soil P legacies in old fields may inhibit the recolonization of native species that are sensitive to, or uncompetitive at, elevated P concentrations. To achieve full recovery, further research is required to test restoration practices aimed at reducing soil P concentrations to facilitate native plant establishment and persistence.

Background and aims The importance of plant-soil feedback is becoming widely acknowledged; however, how different soil conditions influence these interactions is still relatively unknown. Using soil from a degraded old-field and a remnant grassland, we aimed to explore home-field advantages in plant-soil feedbacks and plant responses to the abiotic and biotic soil conditions. We quantified the soil bacterial and fungal community from these sites and their responses to soil conditions and plant species. Methods Sterilized old-field and remnant-grassland soil was inoculated with home or away soil in a reciprocal transplant experiment using a native grass, Rytidosperma auriculatum, and an invasive grass, Avena barbata, as test species. The soil fungal and bacterial communities were characterised using high throughput sequencing. Results Plants had a greater growth response to microbes when an inoculant was added to its home soil. However, this relationship is complex, with microbial communities changing in response to the plant species and soil type. Conclusion The apparent home-field advantage of the soil microbes shown in this study may restrict the utility of inoculants as a management tool. However, since we inoculated sterile soil, future work should focus on understanding how the inoculated microbial community interacts and competes with resident communities.

Protected areas alone cannot conserve all biodiversity; we must also conserve biodiversity within production landscapes. Little is known about spider diversity in the Cape Floristic Region (CFR) biodiversity hotspot and factors driving spider diversity in transformed landscapes. Here, we assess spatial patterns of spiders in different transformed biotopes bordering remnant fynbos natural vegetation patches, determine direction of associated edge effects, and identify environmental factors influencing spider local distribution. Spiders were sampled along replicated transects running from remnant patches into three different transformed biotopes: old-fields (abandoned farmland), vineyards, and alien tree plantations. Spider Shannon diversity within old-fields and plantations did not differ from remnant patches, which had the highest diversity, whereas vineyards had the lowest. Overall, spider diversity was consistently high around habitat boundaries, regardless of land use type. Vineyards showed sharp declines in spider diversity along the remnant-vineyard transect, compared to other transects. Spider assemblages within vineyards was significantly different compared to remnant patches and old-fields, whereas other land-uses showed greater similarity. Plant species richness within the transformed biotope core increased overall spider diversity, benefiting plant-dwelling assemblages, but negatively influencing ground-dwelling assemblages. Herbaceous plant cover was driving assemblages within vineyards, whereas Restionaceae plant cover drove assemblages within old-fields. Furthermore, amount of natural vegetation in the landscape influenced spider assemblages within transformed biotopes. Our results show that old-fields have great potential to increase structural and functional connectivity within agricultural mosaics, and their rehabilitation is recommended. Furthermore, increasing plant diversity throughout the transformed landscape can soften the landscape and benefit spider diversity.

Land abandonment due to increasing depopulation of rural areas is an ongoing trend in developed countries worldwide. Abandoned lands represent an opportunity for ecosystem recovery, an urgent need for biodiversity conservation. Seed dispersal services provided by animals are a key feature for this process. Different dispersers may differentially contribute to plant recruitment under different ecological conditions, leading to complementary dispersal services. We studied the dispersal services, quantified as the contribution to plant recruitment, provided by the main dispersal guilds of Spanish juniper Juniperus thurifera L.: small‐to‐medium‐sized strongly frugivorous birds (thrushes) and medium‐to‐large‐sized carnivorous mammals (red fox and stone marten). To do this, we studied seed fate from seed dispersal to seedling survival during 2 years and estimated seed dispersal effectiveness (seedlings recruited per m²) in two ecological contexts derived from ecosystem recovery after a historical period of degradation: remnant woodlands and old fields. Results showed a clear shift in the contribution to plant recruitment between these guilds, resulting in complementary and non‐redundant dispersal services. Thrushes were the main contributors to plant recruitment in woodlands (73%), leading to population growth but with a reduced impact on the colonization of old fields where carnivores contributed to 80% of recruitment (42% red fox, 38% stone marten). The dispersal complementarity observed for thrushes and carnivores is a consequence of their functional diversity, mainly driven by their differences in feeding and movement behaviour. Synthesis and applications. The combination of short‐distance, strongly frugivorous dispersers (e.g. passerine birds) together with big generalist frugivores with long‐distance movements (e.g. carnivorous mammals) maintained (i) effective seed dispersal services in remnant woodlands and (ii) the connectivity between patches promoting old fields colonization and woodland expansion. Thus, it is in heterogeneous landscape mosaics ecosystems (e.g. agro‐environments) where functionally diverse disperser communities play a key role in ecosystem recovery. By performing effective dispersal services across an array of habitat types, functionally diverse disperser communities assist natural restoration of human‐impacted ecosystems all over the world. Thus, dispersal communities provide an important ecosystem service that may replace costly human‐mediated restoration projects.

Questions Sea level rise and saltwater intrusion are changing low‐lying coastal landscapes, converting agricultural land and other upland habitats to tidal marsh. Abandoned, saline agricultural fields are affected by a unique combination of environmental filters, those traditionally found in tidal marsh — salinity and flooding — alongside those of cultivated lands — high nutrient availability and a history of disturbance. We asked how species composition and functional trait composition in saline fields compares to those in traditional old fields and natural ecotones, and whether trends in succession can be detected in saline fields during the first years post‐abandonment. Location Chesapeake Bay (Mid‐Atlantic, USA). Methods We surveyed plant communities assembling in saline fields and compared taxonomic and functional trait diversity to those in old‐field and marsh–forest ecotone communities. We also assessed changes in the saline fields after two and three years of abandonment to detect the direction of succession. Results Saline fields occupied an intermediate taxonomic and trait space between old fields and marsh ecotones. From old fields to saline fields to marsh, communities were less weedy, and more wetland, native, and perennial. Specific leaf area decreased across this transition, in concordance with expected changes in response to salinity. Over time, saline fields became less graminoid and less weedy, and more native, wetland, and woody. Conclusions We conclude that marsh migration into abandoned farmland is producing a novel assembly of plant communities. Intermediate functional traits in the saline fields reflect the novel environmental filters imposed by saltwater intrusion and the cultivation legacy. These patterns suggest that abandoned, saline agricultural fields may develop somewhat differently than natural marsh boundaries, with more shrub dominance and greater resilience to Phragmites australis invasion. Importantly, these results suggest that saline fields will provide a facilitating route for marsh migration. Saltwater intrusion to agricultural fields is producing a novel assembly of plant species that are a mix of wetland plants and agricultural weeds. Saline‐field plant communities were intermediate in composition and functional traits to old fields and marsh–forest ecotones. Over time, saline fields became less graminoid and weedy, and more native, wetland, and woody, or more like scrub‐shrub wetland.

1. \"Old fields\" are ecosystems that have been previously managed and subsequently abandoned, usually from agricultural use. These systems are classic testing grounds for hypotheses about community assembly. However, old field succession can be difficult to predict: seemingly similar fields often diverge in terms of species composition and environmental conditions. 2. Here, we test the relative roles of contingency and stochasticity in driving vegetative successional dynamics. We draw on three decades of surveys in 24 old fields at the Cedar Creek Ecosystem Science Reserve (Minnesota, USA), and focus on five drivers that are known to shape local plant communities: soil fertility, fire, climate, competition, and demography. These drivers can contribute to contingency when they act consistently across fields and years (e.g., soil nitrogen accumulation, experimental fire regimes, or average climate), or to stochasticity when their effects are variable (e.g., annual variations in weather, or colonization and mortality events). 3. We proceed in two steps. First, we fit regressions estimating abundance, colonization, and mortality for eight major functional groups in relation to these five drivers. We then use these regressions to parameterize a series of metacommunity simulation models, and test whether observed levels of stochasticity and variation in the drivers are sufficient to explain successional divergence. 4. All drivers were significantly associated with plant species abundances, colonization, and mortality. Contingent factors strongly altered predicted successional trajectories. However, replicate simulations with similar conditions followed similar successional trajectories, suggesting that stochastic processes did not lead to divergence. This robustness of successional dynamics may be explained by compensatory trade-offs. For example, species that were abundant late in succession typically suffered from low colonization rates and high mortality rates early in succession. 5. Synthesis. Average successional dynamics among old fields at Cedar Creek follow largely consistent trends. Though dynamics of individual fields vary, much of this variation can be explained by contingent factors. Stochastic processes appear not to be sufficiently strong to create divergent successional trajectories among fields with similar sets of drivers. Our results therefore suggest that divergence among successional trajectories in chronosequences may be the result of predictable contingent factors, rather than unpredictable stochastic fluctuations.

Landscape‐scale restoration requires stakeholder collaboration and recognition of diverse social and ecological motivations to achieve multiple benefits. Yet few landscape restoration projects have set and achieved shared social and ecological goals. Mechanisms to integrate social and ecological motivations will differ in different landscapes. We provide examples from urban, agricultural, and mined landscapes to highlight how integration can achieve multiple benefits and help incentivize restoration. Better communication of ecological and especially social benefits of restoration could increase motivation. Social and economic incentives from carbon markets are evident in agricultural landscapes, biodiversity offset schemes are unlikely to motivate restoration without proof‐of‐concept, and framing restoration in terms of ecosystem services shows promise. Synthesis and applications. When setting restoration goals, it is important to recognize the diverse motivations that influence them. In doing so, and by evaluating both social and ecological benefits, we can better achieve desired restoration outcomes. Customizing incentives to cater for diverse stakeholder motivations could therefore encourage restoration projects. When setting restoration goals, it is important to recognize the diverse motivations that influence them. In doing so, and by evaluating both social and ecological benefits, we can better achieve desired restoration outcomes. Customizing incentives to cater for diverse stakeholder motivations could therefore encourage restoration projects.

AIMS: Across tropical regions, large forest areas have been converted to different agricultural land uses. These uses impose ecological disturbances affecting forest regeneration potential after field abandonment. Finding ways to identify those agricultural land uses limiting forest regeneration is a critical issue for conserving biodiversity in human‐modified landscapes. Here, we developed a fast and inexpensive index, useful for quantifying ecological disturbance regimes associated with agricultural land uses, and tested its power to predict forest regeneration potential. LOCATION: Municipality of Marqués de Comillas, southeast Mexico. METHODS: Interviews were conducted with local farmers to quantify disturbance components (size, duration and severity) associated with agricultural land uses. The scaled values of these disturbance components were added in a simple ecological disturbance index (EDI). In each one of nine recently abandoned fields representing a wide range of EDI values, two 10‐m² plots, one close to and one far from nearby forest remnants, were established. On each plot, all woody plants of 10–100 m in height were counted, identified and measured in four 1‐m² subplots, at the time of field abandonment and 2 yr later. In addition, at each plot, 18 site condition (microclimate and soil) attributes were quantified at the time of abandonment. Plant density, biomass, species richness and species diversity were used as regeneration variables, and EDI and site condition attributes as independent ones. RESULTS: Two years after abandonment, most regeneration variables declined exponentially with EDI. Biomass was not explained by EDI but changed positively with light availability. EDI was strongly correlated to vapour pressure deficit, which also predicted regeneration potential (except biomass). CONCLUSIONS: EDI is a cheap and easy tool for quantifying the ecological disturbance produced by a wide range of agricultural land uses. The index predicted several regeneration variables as well as or better than direct measurements of the site condition at the time of abandonment. EDI can be used to identify biodiversity‐friendly agricultural land uses in human‐modified landscapes.