•Grazing abandonment decreased soil fertility and carbon storage in annual grasslands.•Soil multifunctionality was higher in wet than dry habitats.•Soil multifunctionality decreased with ...abandonment.•Soil multifunctionality was mediated by plant community functional structure.
Extensive livestock grazing is a global land use activity that has numerous social, cultural, and environmental benefits. Many marginal zones grazed for centuries are now suffering from abandonment, which has been found to be interrelated with species and functional diversity loss, and has potential consequences for the provision of ecosystem services such as soil fertility and soil carbon storage. We sampled soil and plant species abundance in a total of 64 plots (5×5m), in wet and dry habitats under different grazing regimes (from moderate grazing to grazing abandonment for at least 30 years) in Central Spain. We tested the influence of grazing intensity and water availability on different variables related to soil fertility and also on soil carbon storage. In addition, Community weighted mean and Rao quadratic entropy were calculated for two effect traits (specific leaf area and plant height), in order to assess the ultimate effects of these functional attributes on multifunctionality (i.e., the provision of several simultaneous ecosystem functions). We found that grazing abandonment generally produces a reduction in soil organic matter, total nitrogen, available potassium and phosphorus, aggregate stability and soil carbon storage. In addition, grazing abandonment had a negative effect on soil texture with loss of fine particles (clay and silt) and water holding capacity, but only in dry habitats and in longer-term abandoned situation. In general, soil multifunctionality was higher in wet than dry habitats, decreased with grazing abandonment in both habitats. Soil multifunctionality was indirectly mediated by the functional structure of size and leaf traits of the local plant communities, but our results suggested that macroscale grazing effects, i.e. translocation of nutrients by grazers among habitats via dung and urine deposition, might be important mechanisms that influence soil multifunctionality at the local level. Agri-environmental policies should be aware of the risk of widespread grazing abandonment and take advantage of the benefits of low-intensity grazing regimes for ecosystem services such as soil fertility and stability, and soil carbon storage.
1. An international group of scientists has built an open internet data base of life-history traits of the Northwest European flora (the LEDA-Traitbase) that can be used as a data source for ...fundamental research on plant biodiversity and coexistence, macro-ecological patterns and plant functional responses. 2. The species-trait matrix comprises referenced information under the control of an editorial board, for ca. 3000 species of the Northwest European flora, combining existing information and additional measurements. The data base currently contains data on 26 plant traits that describe three key features of plant dynamics: persistence, regeneration and dispersal. The LEDA-Traitbase is freely available at http://www.leda-traitbase.org. 3. We present the structure of the data base and an overview of the trait information available. 4. Synthesis. The LEDA Traitbase is useful for large-scale analyses of functional responses of communities to environmental change, effects of community trait composition on ecosystem properties and patterns of rarity and invasiveness, as well as linkages between traits as expressions of fundamental trade-offs in plants.
► Short species, prostrate growth forms and early flowering species disappear with abandonment. ► Tall species and graminoid forms increase with abandonment. ► Soil fertility decreases with ...abandonment.
This paper analyses changes in species richness and functional trait diversity in response to grazing abandonment in Mediterranean grasslands, for five traits that are well connected to ecosystem function and community assembly: Plant Height, Specific Leaf Area, Seed Mass, Onset of Flowering and Growth Form. The impacts of land-use change on floristic composition and community weighted traits were measured along with soil fertility, bare soil cover and litter cover. Results reveal changes in the community average value of all analysed plant functional traits and a loss of functional diversity after abandonment in two of them, which is not accompanied by a change in species richness, indicating a loss of functional groups and a potential effect on the ecosystem functioning.
Abandonment is accompanied by the disappearance of short species, prostrate or creeper growth forms and early flowering species, while tall species and graminoid forms increase, their greater inflammability predicting an increase in wildfire frequency and intensity. Seed Mass and Specific Leaf Area show a weak but significant signal, with abandonment favoring large-seeded species and small Specific Leaf Area. A decline in soil fertility after abandonment is also detected, probably related to the decreased nutrient recycling rate and litter decomposability.
Many dehesa zones in marginal areas are suffering from the abandonment of traditional farming practices. Herbivore grazing affects grassland dynamics, changing the species colonisation and extinction ...relationships via consumption, mechanical disturbance, seed dispersal and altered soil fertility due to dung-borne nutrient input. This paper analyses changes to floristic composition, species richness and heterogeneity as well as soil and light resources in relation to grazing abandonment in two characteristic topography-related types of dehesa habitat (upper slope and lower slope grasslands). Vegetation surveys were undertaken using five replicates in each habitat type in grazed and abandoned grasslands in the Guadarrama range in Central Spain with distric cambisol soils. Additional measurements of light and soil parameters were also undertaken. The results show an effect of grazing on resource availability. In general there was a smaller proportion of fine matter (clay), organic matter, total nitrogen, assimilable potassium and readily available water in abandoned as opposed to grazed zones. We did not find any effect of grazing on phosphorous availability. Abandonment reduces light availability at ground level in lower slope grasslands (wet meadows) but does not produce a significant reduction in upper slope (driest) grasslands, although there is an increased spatial heterogeneity in the availability of light associated with the presence of scattered shrubs. While the total number of species in abandoned zones did not significantly differ from grazed zones, floristic composition changed dramatically with abandonment in both habitat types, with less than 50% of common species. Also, floristic heterogeneity at the small scale increased with abandonment. Designers of agri-environmental policies applied to Mediterranean grasslands should be aware of the risk of widespread grazing abandonment and promote the diversification of grazing regimes across the landscape to maximize species diversity and take advantage of the benefits of low-density grazing in other functions of the ecosystem such as their productivity and stability.
Agri-environmental schemes (AES) have been introduced as part of European Union's (EU) Common Agricultural Policy and are now an important part of this. A methodological approach to analyse the ...policy effects of AES is outlined, in which we distinguish between performance effects (on agricultural practices) and outcome effects (environmental impact). The performance effects are further approached including measurement of improvement and protection effects based on 12 indicators on changes/maintenance of land use and agricultural management.
Data from personal interviews of participating and non-participating farmers in AES measures in nine EU Member States and Switzerland were used to analyse policy effects, including single indicator effects on agricultural practices as well as combined effects at the agreement level. Significant effects were found for mineral N-fertiliser use, stocking density reduction, maintenance of a minimum livestock density and pesticides. For AES agreements regulating grassland management, fertiliser use and pesticides, clear indications of combined improvement and protection effects were found. In addition clear improvement effects of agreements regulating fertiliser and pesticides use on mainly arable lands were revealed. It is concluded that the approach presented including the 12 selected indicators has proven to be operational.
Question: Are seed size and plant size linked to species responses to inter-annual variations in rainfall and rainfall distribution during the growing season in annual grasslands? Location: A 16-year ...data set on species abundance in permanent plots 15 km north of Madrid in a Quercus ilex subsp. ballot a dehesa. Methods: At species level, a GLM was used to analyse the effects of various rainfall indices (total autumn rainfall, early autumn rainfall and spring drought) on species abundance residuals with respect to time and topography. We also assessed the importance of seed size and plant size in the species responses at community level using species as data points. Seed mass and maximum stem length were used as surrogates for seed size and plant size, respectively. Results: Seed mass and plant size may explain some of the fluctuations in the floristic composition of annual species associated with autumn rainfall patterns. Species that are more abundant in dry autumns have greater seed mass than those species that are more abundant in wet autumns. Early autumn rainfall seems to favour larger plants. Conclusions: Our empirical results support the hypothesis that autumn rainfall patterns affect the relative establishment capacity of small and large seedlings in annual species.
Columnar cacti are an important feature of the arid “cardonal” landscape in South America. The predominant columnar cactus in the southern zone is
Echinopsis (=
Trichocereus)
terscheckii. At some ...sites, the species suffers considerable trunk damage, attributed in previous studies to feral livestock grazing (donkey and cattle). In order to understand the potential impact of this damage on columnar cactus populations, we investigated whether reproductive output (flower, fruit and seed production) of
Echinopsis terscheckii individuals was related to damage, controlling for the effect of individual plant size and habitat characteristics measured at meso and micro-scale. Cactus trunk damage negatively correlated with the number of flowers and fruits, but not with fruit size. We also found significant effects of meso and micro-habitat conditions on all the analyzed reproductive parameters while plant size was positively related to flower and fruit production. These results show that bark damage reduces the reproductive potential of cacti, and therefore that large feral herbivores could have negative effects on reproduction of columnar cacti. Such findings highlight the need for management programs to monitor population trends of these plants and also exotic herbivores.
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Echinopsis terscheckii reproductive output was related to bark damage by feral livestock grazing. ► We controlled for the effect of individual plant size and habitat characteristics. ► Cactus trunk damage negatively correlated with the number of flowers and fruits, but not with fruit size. ► Bark damage reduces the reproductive potential of this cactus.
1. We analyse diet and propagule selection by the harvester ant Messor barbarus (L.) in Mediterranean grassland and scrubland in central Spain. 2. Diet was estimated by the identification of ...worker-transported prey in 34 colonies per system type, and compared with seed and fruit availability in the foraging areas. Propagules were characterized by six morphological traits: total weight; weight of seed content; the three main dimensions; and shape. 3. The effect of propagule attributes on selectivity was analysed after transforming data into phylogenetically independent contrasts. Propagules from a small number of species dominate the diet of M. barbarus in the study area, in terms of both frequency and contribution in seed weight. In grassland, prey selection depends on ln(prey length) and ln(prey weight)$(R^{2}=0\cdot 57)$. In scrubland, ln(prey length) explains 64% of selection. Long and heavy propagules are preferred. 4. This pattern of selection can be a mere effect of a time-saving foraging strategy, as apparent preference for long propagules can be expected even if workers forage in a non-selective way. 5. Messor ants are likely to play a role in the plant composition of Mediterranean grassland and scrubland, limiting the abundance of long propagules and thus indirectly favouring small-seeded species without dispersal appendages.
The similarity in species composition between seed bank and vegetation was analysed in Mediterranean grasslands in relation to altitude, topography and grazing. Soil samples were collected in ...permanent plots in autumn at the end of the summer drought period and in spring, before the new seed fall and after the natural winter seed stratification. The seed bank composition was determined by greenhouse germination over a nine-month period. Presence/absence of species in the standing vegetation throughout the complete annual cycle, and the percentage area of bare ground in October, were recorded in the same plots. The species composition of the standing vegetation is clearly determined by altitude, topography and grazing, while the floristic composition of the seed banks is only related to altitude and topography in the case of autumn seed bank and with any of the three factors in the spring seed bank. Relative abundances of grasses, legumes and forbs also show different patterns in vegetation and seed bank data. Sørensen similarity between the autumn seed bank and the vegetation declines as altitude rises, but there are no significant differences for topography and grazing. This similarity decreases in the case of the spring seed bank and does not show any significant relationship with any of the factors. The perennial/ annual ratio and the proportion of bare soil in October are proposed as explanatory variables in a predictive model of similarity between the seed composition of the seed bank and vegetation.
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