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Abstract Organisms have evolved diverse strategies to manage parasite infections. Broadly, hosts may avoid infection by altering behaviour, resist infection by targeting parasites or tolerate infection by repairing associated damage. The effectiveness of a strategy depends on interactions between, for example, resource availability, parasite traits (virulence, life‐history) and the host itself (nutritional status, immunopathology). To understand how these factors shape host parasite‐mitigation strategies, we developed a mathematical model of within‐host, parasite‐immune dynamics in the context of helminth infections. The model incorporated host nutrition and resource allocation to different mechanisms of immune response: larval parasite prevention; adult parasite clearance; damage repair (tolerance). We also considered a non‐immune strategy: avoidance via anorexia, reducing intake of infective stages. Resources not allocated to immune processes promoted host condition, whereas harm due to parasites and immunopathology diminished it. Maximising condition (a proxy for fitness), we determined optimal host investment for each parasite‐mitigation strategy, singly and combined, across different environmental resource levels and parasite trait values. Which strategy was optimal varied with scenario. Tolerance generally performed well, especially with high resources. Success of the different resistance strategies (larval prevention or adult clearance) tracked relative virulence of larval and adult parasites: slowly maturing, highly damaging larvae favoured prevention; rapidly maturing, less harmful larvae favoured clearance. Anorexia was viable only in the short term, due to reduced host nutrition. Combined strategies always outperformed any lone strategy: these were dominated by tolerance, with some investment in resistance. Choice of parasite mitigation strategy has profound consequences for hosts, impacting their condition, survival and reproductive success. We show that the efficacy of different strategies is highly dependent on timescale, parasite traits and resource availability. Models that integrate such factors can inform the collection and interpretation of empirical data, to understand how those drivers interact to shape host immune responses in natural systems.

The relevance of intercropping, where two or more crop species are simultaneously grown on the same land space, is growing due to its potential for improving resource use and maintaining stable yields under variable weather conditions. However, the actual growth of intercropped species may differ resulting from the idiosyncratic effect of crop diversity, and with this, the realized benefits from intercrops are found to depend critically on the cultivar, species, management and environmental conditions. This study aimed to apply a trait-based approach, in which ecological niche spaces are defined through n-dimensional hypervolumes, to identify the contribution of species/cultivar, cultivation design (sole crop or intercrop) and management (low or high fertilization) to the trait diversity of four crop species, pea-barley and faba bean-wheat, when grown as sole crops and intercrops. Four traits were used as trait axes for the trait space analysis: canopy height, shoot biomass, tiller/node number, and grain yield. We found that trait spaces differed with crop species and cultivars, and whether they were grown as intercrops or sole crops. Trait spaces differed between high and low fertilization only for the cereals grown in the more productive site (i.e. Denmark). Species grown as intercrops had larger volumes than when grown as sole crops, as a result of trait plasticity. This response to intercropping was apparent in almost all the species grown in Sweden and Denmark, except for wheat in Denmark. The study demonstrated that individual species responded to intercropping compared to sole cropping through the plasticity of traits, which influenced the shape of the hypervolumes to divide up the trait space between the species. The findings are important in illustrating the plastic responses of arable crops, which are relevant for understanding the productivity of species grown in intercrops as compared to sole crops.

Soil seed banks are reservoirs of plant biodiversity. Here the authors compile a global dataset of soil seed banks in natural plant communities and report a spatially explicit analysis of environmental controls of seed bank density and diversity.

The attribution of biodiversity trends to the action of individual drivers is a first step in developing strategies to conserve, enhance and restore that diversity. One approach to that identification is to link information on species trends with information on ecological preferences that relate to the drivers. Long-term and short-term occupancy trends for 326 bryophyte species (1972–2015 and 2005–2015, respectively) and 437 lichen species (1971–2015 and 2005–2015, respectively) for Scotland were linked with appropriate indicators to assess the action of specific drivers. Bryophyte species of heathlands and woodlands showed positive trends, whilst lichen species from these habitats showed negative trends. Bryophytes and lichens of drier habitats and locations tended to have more positive trends whilst those of wetter habitats tended to be negative. Similarly, evidence suggested that bryophytes and lichens of open areas had more negative trends than those of shadier habitats and that species from both groups of higher fertility habitats had more positive trends than those of less fertile ones. Bryophyte species from warmer areas tended to increase in range. Opposite trends for bryophytes and lichens in heathlands and woodlands suggest competition for space or opposite reactions to other drivers, but it is clear that they should not be lumped into a single functional grouping. There were clear trends for suggesting that increased temperatures (bryophytes only), cumulative nitrogen pollution and reduced land use intensity were shifting assemblages. The overall predominance of negative trends for lichens suggests that many species have lost habitat through decreasing light availability and increased dryness, and potentially through competition with bryophytes. Given the international importance of Scotland for both these groups, these trends for lichens are of concern.

Abstract Phylogenetic diversity quantification is based on indices computed from phylogenetic distances among species, which are derived from phylogenetic trees. This approach requires phylogenetic expertise and available molecular data, or a fully sampled synthesis‐based phylogeny. Here, we propose and evaluate a simpler alternative approach based on taxonomic coding. We developed metrics, the clade indices, based on information about clade proportions in communities and species richness of a community or a clade, which do not require phylogenies. Using vegetation records from herbaceous plots from Central Europe and simulated vegetation plots based on a megaphylogeny of vascular plants, we examined fit accuracy of our proposed indices for all dimensions of phylogenetic diversity (richness, divergence, and regularity). For real vegetation data, the clade indices fitted phylogeny‐based metrics very accurately (explanatory power was usually higher than 80% for phylogenetic richness, almost always higher than 90% for phylogenetic divergence, and often higher than 70% for phylogenetic regularity). For phylogenetic regularity, fit accuracy was habitat and species richness dependent. For phylogenetic richness and divergence, the clade indices performed consistently. In simulated datasets, fit accuracy of all clade indices increased with increasing species richness, suggesting better precision in species‐rich habitats and at larger spatial scales. Fit accuracy for phylogenetic divergence and regularity was unreliable at large phylogenetic scales, suggesting inadvisability of our method in habitats including many distantly related lineages. The clade indices are promising alternative measures for all projects with a phylogenetic framework, which can trade‐off a little precision for a significant speed‐up and simplification, such as macroecological analyses or where phylogenetic data is incomplete.

Ellenberg indicator values for plant species are widely used metrics in ecology, providing a proxy measure of environmental conditions, without direct measurements. They integrate environmental conditions over time since species will only persist where conditions are favourable. Ellenberg moisture (F) values summarise the hydrological environment experienced by plants. However, the relationship between indicator values and hydrological metrics appears to be influenced by a range of other abiotic and biotic factors, limiting our ability to fully interpret Ellenberg F. Focussing on Ellenberg F, we evaluated how the unweighted mean plant community F value to hydrology, specifically water table depth, is influenced by other environmental factors, ground cover type and alpha diversity in UK seasonal coastal wetlands (dune slacks). As expected, water table depth had the strongest influence on unweighted mean Ellenberg F. We show that unweighted mean Ellenberg F was more sensitive to changes in water table levels for plant communities that were more nutrient limited, when the organic matter layer was thicker and there was less bare ground cover. Unweighted mean Ellenberg F was consistently lower for a given water table depth, when there was lower atmospheric nitrogen deposition, lower loss of ignition (a measure of organic matter content) and more diverse plant communities. These findings help us to better interpret what Ellenberg F indicator values tell us about hydrological conditions, by understanding the factors which alter that relationship.

Many countries employ agri-environment schemes to lessen the impact of agriculture on biodiversity. Prioritisation has been a feature of schemes in terms of focussing funding on individual species, habitats or regions. For the 2014–2020 Agri-Environment and Climate Scheme Scotland decided on an alternative prioritisation method; for a number (11) of management options funding was made available for areas (10 km × 10 km grid squares) with more than a threshold of priority species present (a subset of species on the Scottish Biodiversity List likely to benefit from the management options). This approach (Simple targeting) takes no account of the different abundances of the priority species or the possibility that rare species’ distributions are not nested within the more common ones.Three alternative methods were used to assess if that targeting could be made more efficient in its coverage of species’ ranges. Rarity Weighted targeting took into account range sizes of different priority species, Uniqueness targeting focussed on maximising the beta-diversity of targeted grid squares, and Marxan targeting used a reserve selection algorithm to solve the minimum set reserve design problem. Assessment was in terms of how well each method covered the range of the priority species, both on average and on minimum representation of each species on the priority list.Rarity Weighted targeting improved the mean representation of species’ ranges across all 11 options, whereas Marxan targeting performed best of the four methods in ensuring a high minimum representation of species. Uniqueness targeting was uniformly poor. These patterns were conserved whatever the threshold of species richness used in the Simple targeting.If funding for agri-environment options is to be targeted to areas where more species can benefit, then the current Simple targeting approach employed in Scotland can be improved upon in its efficiency at channelling funding to where the priority species are found. However, a strategic choice has to be made as to whether maximising the mean coverage of priority species is the most important objective of the targeting process or whether ensuring high minimum coverage of the species is more important; ensuring that rarer species with ranges poorly nested within those of rarer species are well represented in the targeted areas. Keywords: Agri-Environment and Climate Scheme, Priority species, Scottish Rural Development Programme, Spatial prioritisation, Spatial targeting

Abstract The global scientific community has become increasingly diverse over recent decades, but is this ongoing development also reflected among top‐publishing authors and potential scientific leaders? We surveyed 13 leading journals in ecology, evolution, and conservation to investigate the diversity of the 100 top‐publishing authors in each journal between 1945 and 2019. Out of 1051 individual top‐publishing authors, only 11% are women. The United States, the United Kingdom, Australia, Germany, and Canada account for more than 75% of top‐publishing authors, while countries of the Global South (as well as Russia, Japan, and South Korea) were strikingly underrepresented. The number of top‐publishing authors who are women and/or are from the Global South is increasing only slowly over time. We outline transformative actions that scientific communities can take to enhance diversity, equity and inclusion at author, leadership, and society level. The resulting promotion of scientific innovation and productivity is essential for the development of global solutions in conservation science.

This paper addresses whether the ecosystem service of animal production from grasslands depends upon plant functional identity, plant functional diversity or if the resilience of production is a function of this diversity. Using the results of nine grazing experiments the paper shows that productivity is highly dependent on one leaf trait, leaf dry matter content, as well as rainfall. Animal (secondary) productivity is not dependent on plant functional diversity, but the variability in productivity of grasslands is related to the functional diversity of leaf dry matter content. This and a range of independent studies have shown that functional diversity is reduced at high levels of grassland productivity, so it appears that there is a trade-off between productivity and the resilience of productivity in the face of environmental variation.

Current plant--herbivore interaction models and experiments with mammalian herbivores grazing plant monocultures show the superiority of a maximizing forage quality strategy (MFQ) over a maximizing intake strategy (MI). However, there is a lack of evidence whether grazers comply with the model predictions under field conditions.We assessed diet selection of sheep (Ovis aries) using plant functional traits in productive mesic vs. low-productivity dry species-rich grasslands dominated by resource-exploitative vs. resource-conservative species respectively. Each grassland type was studied in two replicates for two years. We investigated the first grazing cycle in a set of 288 plots with a diameter of 30 cm, i.e. the size of sheep feeding station. In mesic grasslands, high plot defoliation was associated with community weighted means of leaf traits referring to high forage quality, i.e. low leaf dry matter content (LDMC) and high specific leaf area (SLA), with a high proportion of legumes and the most with high community weighted mean of forage indicator value. In contrast in dry grasslands, high community weighted mean of canopy height, an estimate of forage quantity, was the best predictor of plot defoliation. Similar differences in selection on forage quality vs. quantity were detected within plots. Sheep selected plants with higher forage indicator values than the plot specific community weighted mean of forage indicator value in mesic grasslands whereas taller plants were selected in dry grasslands. However, at this scale sheep avoided legumes and plants with higher SLA, preferred plants with higher LDMC while grazing plants with higher forage indicator values in mesic grasslands.Our findings indicate that MFQ appears superior over MI only in habitats with a predominance of resource-exploitative species. Furthermore, plant functional traits (LDMC, SLA, nitrogen fixer) seem to be helpful correlates of forage quality only at the community level.