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Life-cycle of Knautia arvensis covering five stages. The arrows represent yearly transitions and elasticity values of the overall mean matrix are given.  

Life-cycle of Knautia arvensis covering five stages. The arrows represent yearly transitions and elasticity values of the overall mean matrix are given.  

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Grazing is an important management action to conserve biodiversity in semi-natural grasslands but it is important to understand how grazing influences the life-history components and population dynamics of plant species. In this study, we analysed effects of grazing intensity and abandonment on population dynamics of the semi-natural grassland spec...

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... The results of the vote count analysis endorse the importance of maintaining and encouraging traditional practices or short-term abandonment. This result confirms that overgrazing decreases density and richness compared to traditional pastoral activities, as has already been highlighted in many studies (Fleurance, Farruggia, Lanore, & Dumont, 2016;Johansen, Wehn, & Hovstad, 2016;Làzaro et al., 2016;Sonnemann, Buchholz, Rautenberg, & Wurst, 2016;Wang & Tang, 2019). Vote count results were not influenced by any covariate. ...
... This can be explained by the positive effects that a shortterm abandonment can provide in grasslands, while when grazing stops in long-term extensive pastures in woodlands, the abandonment led to a fast woodland progress that is negative for biodiversity. Since woodland can also be considered as a long-term abandonment of grasslands, then only a short-term abandonment of grassland, alternating between grazing and abandonment for a few years can increase biodiversity (Johansen et al., 2016;Koch, Edwards, Blanckenhorn, Walter, & Hofer, 2015;Kouba, Martínez-García, De Frutos, & Alados, 2015). Indeed, meta-analysis showed a clear positive effect of time since abandonment (short to mid-term) on both number of species and individuals, as detailed before. ...
Article
Land-use changes, both in terms of land abandonment and intensification, have led to fragmentation and loss of traditional agricultural habitats. Extensive grazing is among the forms of land use that have undergone the greatest changes. This represents one of the main threats to biodiversity; consequently, a comprehensive overview about the impacts on the biodiversity of changes that are happening in pastoral activities is needed. Moreover, a clear picture of the most widely studied geographical areas, habitats, and taxonomic groups needs to be developed in order to understand the situation. In this framework, we carried out a systematic review and a meta-analysis of the publications related to the impacts of pastoral activities on animal biodiversity in Europe. We analysed 223 articles by searching the ISI Web of Science platform and combining keywords related to "pastoral activities" and "biodiversity indicators”, applying a vote count approach, i.e. simply dividing articles into categories depending on their results (non-significant ones, significant positive results, significant negative ones). Moreover, we conducted a meta-analysis on 33 articles, selecting those focusing on Arthropods (the most studied taxa). To understand the main gaps in this scientific topic, we focused on: i) the identification of the geographical, environmental, and temporal structure of the studies; ii) the description of the main target groups used as bio-indicators; iii) the comparison of different management practices (overgrazing, traditional, agri-environment schemes - AESs), plus land abandonment, to determine which is the best for biodiversity conservation and to evaluate the effectiveness of AESs. There was a bias towards lowlands in comparison to uplands, as well as a lack of long-term studies. Plants were more sensitive than animals to grazing changes. Arthropods’ orders are the taxa used most frequently as indicators, in comparison with vertebrates, especially birds. We identified a generalised negative impact of overgrazing in all the habitats and geographical areas, apparently except in mountainous shrubland. Conversely, land abandonment resulted in a negative influence on biodiversity only in the mountainous areas of southern Europe (underlining the important role of traditional activities), whereas short term abandonment had a beneficial role in central Europe, where overgrazing was more widespread. The meta-analysis suggested that arthropod richness was higher in short to mid-term abandoned pastures than under either extensive or intensive grazing systems. Finally, the effectiveness of AESs for conservation purposes was not confirmed by the vote count approach, whilst meta-analysis detected a positive effect for Arthropods of these same management practices when compared to overgrazing. We highlight a lack of data on AESs, especially when compared with traditional extensive grazing or abandonment. Our findings suggest that AES seems to effectively mimic traditional pastures, contrasting overgrazing, which is one of its main goal. Since AES have a strong potential in influencing sustainable management and promoting biodiversity conservation, the European Union should focus on the most effective and well targeted AES based on research, and further studies will be necessary to continuously assess their effect.
... The ramets are only partly autonomous, which enables them to benefit from nutrients (nitrogen, phosphorus, potash, and urea) and photosynthates (sugars, amino acids, and hormones) made available by already existing ramets of the same genet (Lei, 2010). Previous studies (Evette et al., 2009;Johansen, Wehn, & Hovstad, 2016;Lei, 2010) found that the budding potential and ramet production of clonal herbs in disturbed environments is higher than in undisturbed environments. Consequently, the clonal growth and fugitive establishment of Neopicrorhiza could partly remediate the impact of low-intensity harvest in disturbed populations. ...
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A surprisingly large number of species potentially threatened by human harvest lack quantitative ecological studies incorporating harvest effects, especially clonal species in the alpine Himalayas. We studied density and biomass variation of a threatened medicinal herb, Neopicrorhiza scrophulariiflora, to examine the effect of harvest on plant performance. The study covered two regions with contrasting harvest situations—one with open‐access and another protected from commercial harvesting. Four populations from each region were compared along an elevation gradient (3,800–4,800 m). Also, we conducted in situ interviews with 165 and 38 medicinal and aromatic plant users in open‐access and protected regions, respectively, to assess the collection and use patterns of the target species. The quantity harvested per household for traditional healthcare use was similar in both regions. We found no evidence of trade‐driven collection in the protected region but in the open‐access region a trade‐based annual collection of 35–465 kg dried rhizomes per household had a strong negative effect on both density and biomass. In the protected region, the effect of harvest intensity on plant density was positive for vegetative and negative for reproductive individuals, whereas in the open‐access region, the effect was negative for both vegetative and reproductive individuals. The results indicated that a low harvest intensity had no adverse impact on N. scrophulariiflora populations; however, quantification of the optimum level of harvest remains to be explored. Shrub vegetation appeared to buffer the harvest impact on plant density, possibly through the retention of additional moisture. To maintain population viability, we suggest regulating harvest, for example, by introducing rotational harvest systems, ensuring that a sufficient number of reproductive individuals are left as a source of propagules in each harvested population and that populations are given time to recover between harvests. The interaction between human harvest, habitat characteristics, and plant growth strategies is a persistent ecological issue. In the alpine Himalayas, the issue is sparsely explored, particularly for clonal plants commercially harvested from the wild. Hence, in this study we examine density and biomass of Neopicrorhiza scrophulariiflora and its response to harvest depending on vegetation, substrate conditions, and anthropogenic regimes to understand the causal factors involved. Our results indicate that low harvest intensity was acceptable to the plant populations, particularly in an area where exploitation was regulated. Shrubland meadow populations were heavily exploited in one area but appeared more resilient to extraction than other commercially exploited populations. We suggest the development of in situ management regimes and sustainable harvest strategies for long‐term conservation.
... Salix caprea), which establish in abandoned areas, serve as important food sources for pollinators (Totland et al. 2013). It is important, to recognize that the results shown in this case study, might be due to a time-lagged species turnover after abandonment which can allow plants that are attractive to the pollinators to exist for decades in the abandoned areas (Johansen et al. 2016). The timelag may result in the presence of the same species in both managed and abandoned semi-natural grasslands and therefore similar food sources for pollinators although this is not explored in detail here. ...
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Understanding how drivers of change affect ecosystem services (ES) is of great importance. Indicators of ES can be developed based on biophysical measures and be used to investigate the service flow from ecosystems to socio-ecological systems. However, the ES concept is multivariate and the use of normalized composite indicators reduces complexity and facilitates communication between science and policy. The aim of this study is to analyze how land use change affects ES and species richness and how the effects are modified by environmental factors by using composite indicators based on biophysical indicators. Using multivariate and regression analyses, we analyze the effect of grazing management abandonment in semi-natural grasslands in Norway on six ES: nutrient cycling, pollination, forage quality, aesthetics and global and regional climate regulation in addition to species richness along soil and climate gradients. Nutrient cycling, forage quality, regional climate regulation, aesthetics and species richness are larger in managed compared to abandoned grasslands. There are trade-offs among ES as different management strategies provide various ES and these trade-offs vary along environmental gradients. Management policies that aim to conserve ES need to have conservation goals that are context dependent, should recognize ES trade-offs and be adapted to local conditions.
... 4 NB. Farmer S13 is not the neighbour of farmer S10 5 This has been shown to be a likely outcome for Knautia arvensis (Johansen et al. (2016)). regime that allow cutting dates to vary between years and between hay meadows. ...
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Worldwide semi-natural habitats of high biological value are in decline. Consequently, numerous Agri-Environment Schemes (AESs) intended to halt biodiversity loss within these habitats have been implemented. One approach has been the application of "adaptive management", where scientific knowledge is applied alongside the traditional ecological knowledge (TEK) of stakeholders in order to establish an integrated approach that is adjusted as outcomes are assessed. In this paper we examine the effectiveness of the adaptive management approach of Norway's Action Plan for Hay Meadows (APHM). Twenty-nine hay meadows from fourteen farms in the county of Møre og Romsdal were ecologically surveyed over a 2 year period. Interviews were also conducted with owners and land managers to explore TEK and management issues. The inter-disciplinary study found that the disembedding of hay meadow management from its initial commercial purpose (in particular the loss of much of the livestock from the region) has contributed to a significant loss of TEK-which is now largely limited to knowledge of how the fields were managed recently. While, the APHM is limiting biodiversity decline by promoting traditional practices there were indications that the standardisation of management actions might negatively affect species composition in the long term. More critically, continued farm abandonment within the region means that without alternatives to management by farmers many of these meadows are likely to disappear in the next couple of decades. We conclude that adaptive management provides an effective short-term means of preserving hay meadows, but long term conservation will require a means of addressing the continued decline of local farming communities.
... Besides, the indicator value of tundra ecosystems could be enhanced if cryptogams are considered, given that they represent different functional groups with different microhabitat requirements and distribution patterns across elevations . Finally, also long-term monitoring studies are essential when studying climate-change impacts on tundra plant communities, as these often bear the imprint of past climatic changes (Johansen et al. 2016). Especially for lichens and bryophytes, which are generally slow-growing (Ahti 1977), long-term observation records are of major importance, but these are to date still scarce. ...
... En konsekvens av at slått ofte gjennomføres før frø er produsert, vil derfor vaere at plantene kun spres vegetativt. Vegetativ vekst og lang levetid for individer kan fungere som en buffer mot eventuelle miljøendringer som kan påvirke populasjonsstørrelsen ( Johansen et al. 2016). Den vegetative veksten kan dermed bidra til at populasjonene opprettholder sin størrelse til tross for at de ikke produserer modne frø. ...
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Prosjektets mål har vært å evaluere avgjørende aspekter, både økologiske og samfunnsmessige, ved Handlingsplan for slåttemark. Mulighetene for adaptiv skjøtsel og bruk av tradisjonell økologisk kunnskap (TRØK) er hovedtema. For å sikre en enda bedre forvaltning av biologiske verdier knyttet til slåttemark er det basert på prosjektets resultater definet ni anbefalinger. The overriding objective of this project is to integrate scientific and traditional knowledge and evaluate ecological and social implications for the adaptive management suggested in the Action Plan for Hay Meadows in Norway (APHM). Based on the results from the project the project has defined nine recommendations.
... Besides, the indicator value of tundra ecosystems could be enhanced if cryptogams are considered, given that they represent different functional groups with different microhabitat requirements and distribution patterns across elevations . Finally, also long-term monitoring studies are essential when studying climate-change impacts on tundra plant communities, as these often bear the imprint of past climatic changes (Johansen et al. 2016). Especially for lichens and bryophytes, which are generally slow-growing (Ahti 1977), long-term observation records are of major importance, but these are to date still scarce. ...
Article
Climate change is affecting the composition and functioning of ecosystems across the globe. Mountain ecosystems are particularly sensitive to climate warming since their biota is generally limited by low temperatures. Cryptogams such as lichens and bryophytes are important for the biodiversity and functioning of these ecosystems, but have not often been incorporated in vegetation resurvey studies. Hence, we lack a good understanding of how vascular plants, lichens and bryophytes respond interactively to climate warming in alpine communities. Here we quantified long-term changes in species richness, cover, composition and thermophilization (i.e. the increasing dominance of warm-adapted species) of vascular plants, lichens and bryophytes on four summits at Dovrefjell, Norway. These summits are situated along an elevational gradient from the low alpine to high alpine zone and were surveyed for all species in 2001, 2008 and 2015. During the 15-year period, a decline in lichen richness and increase in bryophyte richness was detected, whereas no change in vascular plant richness was found. Dwarf-shrub abundance progressively increased at the expense of lichens, and thermophilization was most pronounced for vascular plants, but occurred only on the lowest summits and northern aspects. Lichens showed less thermophilization and, for the bryophytes, no significant thermophilization was found. Although recent climate change may have primarily caused the observed changes in vegetation, combined effects with non-climatic factors (e.g. grazing and trampling) are likely important as well. At a larger scale, alpine vegetation shifts could have a profound impact on biosphere functioning with feedbacks to the global climate.
... This increases opportunities for germination and seedling establishment, especially for smallseeded species (Kahmen & Poschlod 2008). In abandoned grasslands, the field layer is often quite dense, plant litter often accumulates at the soil surface, gaps with bare soil are less frequent than in managed grasslands and regeneration by seed is quite rare (Hamre et al. 2010;Johansen et al. 2016). Species with large seeds are expected to have an advantage compared to species with smaller seeds in abandoned grasslands as the former often produce seedlings with a better ability to penetrate the litter layer and establish under closed vegetation (Kahmen & Poschlod 2008). ...
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Questions What are the effects of abandonment on plant diversity in semi-natural grasslands? Do the effects of abandonment on taxonomic and functional diversity vary along environmental gradients of climate and soil? Location West and Mid Norway. Methods Plant composition was surveyed in 110 subplots of 4 m2 in 14 sites across grazed and abandoned semi-natural grasslands. Climate data were extracted and soil composition analysed. To reduce the number of explanatory variables and deal with collinearity, we performed principal component analyses (PCA). Data on the plant species vegetative height (H), leaf dry matter content (LDMC), specific leaf area (SLA), seed mass (SM), and number of seeds per plant (SNP) for 175 plant species were extracted from the LEDA database. Measures of plant diversity (species richness, community weighted mean of functional traits (CWM) and functional diversity (evenness and range)) were calculated for each subplot. To estimate the effects of abandonment on plant diversity and examine how these effects are moderated by gradients in soil and climate, we fitted mixed models to the data including sites as a random effect. Results Species richness in the subplots was lower in abandoned semi-natural grasslands, especially on more calcareous soils. CWM H, LDMC, and SM were higher in abandoned semi-natural grasslands. CWM LDMC was only higher in the driest subplots. The ranges in H, SLA, and SM as well as evenness in LDMC were also higher in abandoned semi-natural grasslands but the range in LDMC was lower. Conclusions It is important to assess both taxonomic and functional diversity to understand ecosystem processes. The species pool in ecosystems influenced by a long history of intermediate grazing include a high proportion of low stature, grazing tolerant plant species. Abandonment of extensive land-use practices will cause a decline in taxonomic diversity (plant species richness) in such systems due to increased abundances of plants of high stature which outcompete the lower, grazing tolerant plants. This process is predominant especially if moisture, soil fertility and pH are at intermediate levels. Changes in species communities due to abandonment will also influence ecosystem functioning, such as nutrient turnover and fodder production resilience.
... Maintaining connections after establishment forms groups of ramets that are often physiologically integrated. In many clonal species, connected ramets can exchange signals and resources such as water, nutrients, and carbohydrates, and thereby increase their collective performance and survival (e.g., Roiloa et al., 2007;De Kroon et al., 2009;Kui et al., 2013;Song et al., 2013;Touchette et al., 2013;You et al., 2014a;Roiloa et al., 2014;Luo and Zhao, 2015;Johansen et al., 2016). On the other hand, fragmentation of groups by breakage or senescence of connections can form vegetative propagules that disperses more readily and widely than intact groups of ramets (e.g., Boedeltje et al., 2008;Dong et al., 2012;Lin et al., 2012;Roiloa and Retuerto, 2016). ...
Article
Clonal integration and fragmentation are potentially competing advantages of clonal growth. Clonal fragmentation can increase the dispersal of ramets, but it prevents physiological integration, which can increase the growth of clones and may increase their competitive effect on other plant species. We tested whether fragmentation can reduce the competitive effect of invasive clonal plants within mixed communities and whether this effect of fragmentation is greater under conditions in which the competitive effect of a clonal plant is greater. We constructed wetland communities each consisting of four common, co-occurring, mainly aquatic plant species under flooded and unflooded conditions, and compared the growth of the species with and without intact or fragmented groups of ramets of the widespread, amphibious, invasive clonal plant Alternanthera philoxeroides. We measured the community-level competitive effect of A. philoxeroides on the four aquatic plant species. Fragmentation reduced mass accumulation of A. philoxeroides, but did not reduce its competitive effect, either under flooded or under unflooded conditions. One explanation is that A. philoxeroides was able to maintain production of new ramets when fragmented. Clonal plants may thus mitigate trade-offs between the potential ecological advantages of physiological integration and fragmentation by maintaining rates of vegetative reproduction after fragmentation, even when total growth is reduced.
... The accumulating litter layer in forests may inhibit seed germination and result in a decrease in annual species or perennial species that do not vegetatively reproduce (Izhaki et al. 2000). The clonal spread of many perennial forbs may minimize the effect of the litter layer in the forest and enable access to resources from neighboring environments, like the adjacent grasslands, thereby enabling relatively rapid recolonization of, and persistence in, afforested sites and potentially contributing to greater richness of these species in forested habitats (Fahrig et al. 1994;Johansen et al. 2016). ...
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The Campos grasslands of southern South America have been affected by long-term livestock grazing and increasingly widespread afforestation, but the effects of multiple disturbances have not been well studied, especially at multiple spatiotemporal scales. To determine vegetation response to these disturbances, we constructed grazing exclosures bisecting the forest-grassland ecotone at five sites and measured species richness in nested plots for four treatments (grazed forest, ungrazed forest, grazed grassland, and ungrazed grassland) over 18 months. Species-area curves revealed greater small-scale species richness in grasslands than forests but greater rates of species accumulation in forests and thus little difference in richness between habitats at larger scales. Temporally, small-scale richness differed among sample dates, but rates of species accumulation did not. The interactive effect of habitat and management on total species richness varied with times since the exclosures were built. Grazing and afforestation interactively affect the vegetation of the Campos, as plants respond to changes in both disturbances; over the duration of this study, the removal of grazing decreased species richness in grasslands but increased richness in forests. Our results illustrate that the response of plant species richness to grazing and afforestation varies by the nature of the disturbance mechanism, and that multiple disturbances have complex interactive effects on vegetative responses.