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Abstract: As a compensatory response to herbivory, plants may branch vigorously when the growth of dormant meristems is triggered by shoot damage. Undamaged plants, on the other hand, often restrain branching, and this limitation on growth can be considered a cost of tolerance to herbivory. Restrained branching is caused by apical dominance and may, alternatively, be associated with fitness benefits in competitive environments that favor fast vertical growth. To test these hypotheses regarding selection for restrained branching, we compared the performance of two subspecies of the biennial grassland herb Gentianella campestris; the tall, apically dominant ssp. campestris and the short, multi‐stemmed ssp. islandica, which shows reduced apical dominance. For both subspecies, we manipulated the height of surrounding vegetation (competition) and damage intensity in grasslands of differing productivity (high, medium, low), and examined population growth rates using matrix population models combined with life table response experiments. In the absence of damage, ssp. campestris exhibited a higher population growth rate than ssp. islandica in the tallest vegetation, however with the growth rate still being below one. In the medium and low productivity environments where the vegetation was shorter, the population growth rate of ssp. islandica was considerably higher than that of ssp. campestris as long as no more than about 50% of the plants were damaged. When plants were damaged, the apically dominant ssp. campestris showed a positive population growth rate (λ > 1) and often overcompensatory seed production in all productivity levels, while ssp. islandica showed no compensation and therefore the population was predicted to decline (λ < 1). We conclude that restrained branching in Gentianella cannot be selected for by competition alone, but that episodes of apical damage are required to maintain the trait. Furthermore, because of the costs of restrained branching, apical dominance should be selected against in grasslands where competition and disturbance are low. [ABSTRACT FROM AUTHOR]

This research compares the production of hay in three historical European agro-ecological systems: in northern Romania, central Sweden and eastern central France. We analyse hay production in relation to the entire production system, the local natural conditions, and the variety of ways by which hay production was transformed over time. We found broad commonalities, but also discovered significant differences in each of three historical trajectories. Introduction of fodder crops, crop rotations and mechanization are important drivers of changes in all three areas, although the timing, sequence and causation vary from place to place. There are significant differences in the organization of farm labour, in the role of beef and dairy production, the role of political reforms and the climatic constraints of outdoor grazing which affected the transformation of fodder production. "is paper highlights the potential of an integrated, interdisciplinary approach for better understanding the complex interaction of people, their social and economic contexts, and their environment. [ABSTRACT FROM AUTHOR]

The article discusses a study on investigation of Arthropod communities in two Swedish semi-natural grasslands, two types of grazing regime one conventional grazing and another traditional late management. It discusses various explanation regarding effects of grazing season on a number of habitat variables like temperature, food resources, structure of vegetation, and disturbance. Litter and tall vegetation in late grazing may increase prey abundance, attracting predators to the treatment area.

The reformation of the Swedish agricultural system, about 150years ago, drastically changed the use of semi-natural grasslands. Grassland plant diversity has declined due to abandonment, changed management methods and production intensification. Current diversity patterns are thus a result of historical and current land use in combination. In this study we investigate the relative importance of historical grassland management and current land use for grassland plant diversity. The distribution of 128 grassland plant species in an agricultural landscape in southwest Sweden was analysed in relation to current land use and land use in three historical time periods; the 18th and the 19th century and around 1960. Land use during the three historical periods was also combined into land-use sequences. Four diversity estimates were used: number of grassland species, number of grassland specialists, Shannon–Wiener index on the specialists and total cover/hectare of specialists. Historical land use – especially 18th century and the land-use sequences – explained more of the variation among study sites than did current land use. Continuity of a specific management type was important for grassland plants as indicated by highest diversities being found in pastures continuously grazed since the 18th century. Former hay meadows, currently grazed, did not differ in any diversity estimate from abandoned hay meadows, indicating that change of management from mowing to grazing a century ago may cause diversity declines similar to abandonment some 40years ago. Limited artificial fertilisation in the managed areas may have contributed to this effect. Further decline in grassland biodiversity in the agricultural landscape is expected because a substantial proportion of grassland plant populations occur in abandoned areas. [Copyright &y& Elsevier]

In order to estimate how much population extinction risk may be affected by local fragmentation, population viability analyses were performed in six populations of the endangered grassland herb Gentianella campestris in Sweden. The populations had been experimentally reintroduced to grasslands that were locally fragmented by juniper shrubs. The sites represented three sizes of grassland and two levels of grassland abundance in the landscape. Five years' demographic data were evaluated in a stochastic matrix population model, and studies of seed set, pollinator abundance, and inbreeding depression were performed in order to examine possible links between population viability and pollination. In all six sites, plants with reduced capacity of self-pollination (due to herkogamy) showed strongly reduced population viability in locally fragmented grassland habit, with pronounced extinction thresholds at certain levels of local fragmentation. Population viability was reduced because of inbreeding depression and reduced seed production in combination, both caused by pollinator deficit in locally fragmented grasslands. Plants with high selfing capacity had low population viability over the entire local fragmentation gradients. Selfing yielded high seed set in the absence of pollinators and was advantageous in fragmented parts of the grasslands. However, selfing had negative effects in nonfragmented parts of the grasslands, because it decreased the chances of cross-pollination and because selfed progeny had reduced fitness compared to outcrossed offspring. A comparison among the six sites indicated that the negative effects of local fragmentation were amplified by reduced size of the grassland sites and by reduced abundance of grassland habitat in the landscape. To my knowledge, this is the first quantitative estimate of increased extinction risk in fragmented plant populations. [ABSTRACT FROM AUTHOR]

Summary 1 Transition matrix models were used to evaluate the effects of environmental stochasticity and four different methods of grassland management on dynamics and viability of a population of the biennial Gentianella campestris (Gentianaceae) in species-rich grassland. Data were collected between 1990 and 1995. 2 Continuous summer grazing, the prevailing management strategy in Scandinavian grasslands, resulted in high recruitment of new plants, mainly because litter accumulation was prevented and gaps were created by trampling. Trampling and repeated grazing, however, caused damage which reduced seed production. Lambda for the average matrix was c. 0.77, and a stochastic matrix model yielded an extinction probability for the total population of c. 0.08 within 50 years. 3 Mowing in mid-July (used as a conservation tool) increased seed production, but litter accumulation following re-growth of the vegetation prevented establishment. Lambda and extinction risk were similar to continuous grazing. 4 Mowing in October (another conservation tool) promoted recruitment because of low litter accumulation, but the seed output decreased because plant growth was impaired by tall vegetation. Lambda was 0.64, while the extinction probability was very high (c. 0.98 within 50 years). 5 Mid-July mowing followed by autumn grazing (the historical management regime) yielded high values for both seed production and establishment of rosettes. Lambda was 0.94 and the probability of extinction within 50 years was below detection level. 6 Log-linear analysis showed that the matrices differed significantly both between treatments and between years. The latter indicates environmental stochasticity, here caused by summer drought that increased the extinction risk. Lambda may be slightly underestimated because drought occurred in one out of five summers during the study period, which is high compared with the natural frequency. 7 We conclude that traditional grassland management is more... [ABSTRACT FROM AUTHOR]

Investigates how populations of Gentianella campestris (G. campestris) responded to damage at various occasions during the vegetation period. Research methods used; Detailed information on G. campestris; Comparison of equally sized clipped and unclipped plants in two populations in central Sweden; Results of this investigation.

Focuses on the impact of overcompensation on the Gentianella campestris plant. Information on overcompensation; Advantages and disadvantages of overcompensation; Information on the plant; Conditions under which the plant grows.

Semi-natural hay meadows are among the most biodiversity-rich terrestrial ecosystems, and are managed for conservation purposes in most of Europe, including Sweden. Romania has some of Europe's largest areas of grasslands still managed with traditional methods. Through interviews and field studies, current management practices were investigated in two Romanian villages, and compared with CAP-generated grassland management in Swedish hay meadows and historical Swedish management of grasslands. The study evaluated the effect of the eligibility criteria within both countries’ National Rural Development Programmes (NRDPs) on different ecologically important components of hay meadow management. The success of Swedish management was measured by assessing population trends for 25 grassland plant species. Current management proved to be considerably more diverse in Romania than in Sweden, but historical Swedish management was similar to management in Romania. Both countries’ NRDPs provide support for some management components, but create barriers against other components. The Romanian NRDP contained more barriers than the Swedish NRDP, yet Swedish management showed little success in preserving grassland plants. NRDPs should nourish the use of local and traditional knowledge in order to preserve biodiversity in semi-natural grasslands. There are major limitations in both countries’ NRDPs. [ABSTRACT FROM PUBLISHER]

Biomass removal by herbivores usually incurs a fitness cost for the attacked plants, with the total cost per unit lost tissue depending on the value of the removed tissue (i.e., how costly it is to be replaced by regrowth). Optimal defense theory, first outlined in the 1960s and 1970s, predicted that these fitness costs result in an arms race between plants and herbivores, in which selection favors resistance strategies that either repel herbivores through morphological and chemical resistance traits in order to reduce their consumption, or result in enemy escape through rapid growth or by timing the growth or flowering to the periods when herbivores are absent. Such resistance against herbivores would most likely evolve when herbivores are abundant, cause extensive damage, and consume valuable plant tissues. The purpose of this Special Feature is to celebrate the 30th anniversary of the phenomenon of overcompensation, specifically, where the finding has brought us and where it is leading us 30 yr later. We first provide a short overview of how the phenomenon of overcompensation has led to broader studies on plant tolerance to herbivory, summarize key findings, and then discuss some promising new directions in light of six featured research papers. [ABSTRACT FROM AUTHOR]

The invasive herb Lupinus polyphyllus has been focus of a number of fact sheets worldwide but a comprehensive summary of the species' taxonomy and morphology, distribution, habitat requirements, and biology has been lacking. This paper gives a thorough account of the species' systematic position and taxonomy, highlighting the difficulties to delimit taxa, which is related to interbreeding among members of this genus. However, L. polyphyllus var. polyphyllus is apparently the taxon that has naturalized and is regionally invasive in temperate-humid climates worldwide. We also present an updated distribution map of L. polyphyllus in the native and invaded ranges, which highlights seven regions in the world where the species has been established. We show that the climatic niche of L. polyphyllus in the invaded range shifts towards higher summer precipitation and lower isothermality, probably because the invaded range includes subcontinental regions of eastern Europe and western Siberia. The habitats of L. polyphyllus range from rather dry to wet, have moderately acidic to strongly acidic soils, and the species' indicator values across Europe suggest that it occurs along a gradient from very nutrient poor sites to intermediate to rich sites from northern to southern Europe. The species shows high resistance to both drought and frost. In Central Europe, the species has a stronghold in alpic mountain hay meadows, abandoned meadows and pastures, low and medium altitude hay meadows, anthropogenic herb stands and temperate thickets and scrubs. In northern Europe, the species occurs in anthropogenic herb stands along roads and railroads as well as in abandoned pastures and fields. We also found some doubtful information about L. polyphyllus in the literature. This refers to its description as "rhizomatous perennial" although it lacks rhizomes; an apparently very high longevity of its seeds, which may only be true under artificial conditions in an ex situ seed repository; and a very deep rooting depth, which may not represent the average rooting depth but rather an extreme value. Knowledge about the interrelationships between the species' future population dynamics and spread and ongoing climate warming is lacking. Finally, our review points out that there is currently no evidence-based strategy for a cost-efficient management of L. polyphyllus although it is among the most problematic non-native plant species in Europe due to its environmental and socio-economic impacts. • A timely account of the biology of Lupinus polyphyllus. • Comprehensive review of the species taxonomy and distribution. • Distributions maps for North-America, Europa and the world. • Original figure of the species life cycle. • Comprehensive discussion of potential management options. [ABSTRACT FROM AUTHOR]

Semi-natural hay meadows are species rich habitats, formed by a long history of management and they have experienced a drastic decline all over Europe. There is a vast literature on conservation and species diversity of semi-natural hay-meadows, but very limited information on historic timing of hay cutting. We analyzed data collected between 1873 and 1951 on hay cutting dates and phenology of six plant species from farms distributed across Sweden. The data set comprised 16,015 observations from 175 sites. Results show that date of start and end of hay cutting varied across Sweden. The start of hay cutting was generally delayed by 2.2 days per latitudinal degree and 1.5 days per 100 m altitude, while the end of hay cutting was generally delayed by 2.9 days per latitudinal degree and 2.5 days per 100 m altitude. The average hay cutting period was 18.5 ± 6.6 days, and became slightly shorter northwards. Site-specific factors had a great impact on when hay cutting was performed, as indicated by a significant correlation between flowering (and leafing) phenology in other species and start date of hay cutting. Today, management for conservation is usually related to a calendar date (e.g. regulated in eligibility criteria and requirements for payment in agri-environment programs in EU). In order to mimic historic management that formed this habitat, management should instead account for latitude and altitude, between-year variation in timing of hay cutting, variation in both start and end dates of hay cutting and if possible local phenological conditions. [ABSTRACT FROM AUTHOR]

Roadsides, in particular those being species-rich and of conservation value, are considered to improve landscape permeability by providing corridors among habitat patches and by facilitating species' dispersal. However, little is known about the potential connectivity offered by such high-value roadsides. Using circuit theory, we modelled connectivity provided by high-value roadsides in landscapes with low or high permeability in south-central Sweden, with 'permeability' being measured by the area of semi-natural grasslands. We modelled structural connectivity and, for habitat generalists and specialists, potential functional connectivity focusing on butterflies. We further assessed in which landscapes grassland connectivity is best enhanced through measures for expanding the area of high-value roadsides. Structural connectivity provided by high-value roadsides resulted in similar patterns to those of a functional approach, in which we modelled habitat generalists. In landscapes with low permeability, all target species showed higher movements within compared to between grasslands using high-value roadsides. In landscapes with high permeability, grassland generalists and specialists showed the same patterns, whereas for habitat generalists, connectivity provided by high-value roadsides and grasslands was similar. Increasing the ratio of high-value roadsides can thus enhance structural and functional connectivity in landscapes with low permeability. In contrast, in landscapes with high permeability, roadsides only supported movement of specialised species. Continuous segments of high-value roadsides are most efficient to increase connectivity for specialists, whereas generalists can utilize also short segments of high-value roadsides acting as stepping-stones. Thus, land management should focus on the preservation and restoration of existing semi-natural grasslands. Management for enhancing grassland connectivity through high-value roadsides should aim at maintaining and creating high-value roadside vegetation, preferably in long continuous segments, especially in landscapes with low permeability. • Connectivity through high-value roadsides depends on landscape permeability. • A structural approach can be used to model connectivity for habitat generalists. • A functional approach is needed for modelling connectivity for specialised species. • Connectivity can be enhanced by high-value roadsides in areas with low permeability. • Long roadside sections targeted to connect high-value grasslands boost connectivity. [ABSTRACT FROM AUTHOR]