Traditional crofting management supports and maintains machair floral diversity

Grazing systems in the high Himalayas are changing in response to socioeconomic factors and policy decisions. As well as effects on livelihood of herders, such changes may have significant impacts on plant species richness and composition. The objectives of this study were to explore how plant species richness and composition respond to livestock grazing in the high Himalayan rangelands. The study was conducted in three mountainous Protected Areas of Nepal viz. Sagarmatha (Mt Everest) National Park, Gaurishankar Conservation Area and Khaptad National Park. Species and environmental data were collected along perpendicular transects outwards from goths (semi-permanent stopping and camping points). It was found that the distance from goths generally represents a grazing disturbance gradient. The core areas near goths had low species richness per plot (α-diversity) where nitrophilous and grazing-tolerant species were commonly found. However, the highest species richness, total numbers of species and occurrences of rare species at mid- and farther distances from goths within 800 m suggest that negative effects of summer livestock grazing were small and confined to limited areas near goths. Altitude, soil moisture content, percentage shrub cover and distance from goths were the variables significantly correlated with species composition, although the relative importance of these factors varied across study sites. This research can be used to inform decision-making about seasonal livestock grazing in the Himalayan rangelands, which should incorporate both ecological as well as socioeconomic considerations.

ABSTRACTBackground: Increased soil phosphorus (P) caused by agricultural intensification has been associated with decreased plant species richness (SR) in central Europe. How plant communities and soil P gradients are related in unimproved open habitats remains unclear.Aims: The aim of this article was to characterise the relationship between soil chemical parameters and plant species composition and richness in unimproved open habitats.Methods: The influence of soil chemical parameters (pH, P, K, Mg) on species composition was assessed, using data from 40 heathland and 54 grassland plots, by non-metric multidimensional scaling and permutational multivariate analysis of variance. The relationship between soil chemical parameters and SR was tested by linear mixed effects models.Results: A direct relationship between heathland community composition and pH was observed, explaining 10% of variation in species composition, while P, Mg and pH together explained 17% of variation in grassland composition. In heathlands, SR increased with increasing pH, whereas in grasslands, SR decreased with increasing soil P.Conclusions: Soil chemical parameters were substantially related to plant community composition and richness. In an area spared from a century of agricultural intensification, reduced pH appeared to constrain SR in heathlands, while even slight P increases (<10 mg kg−1) depressed plant SR in semi-natural grasslands.

Temperate semi‐natural grasslands are known for their high plant species richness at small spatial scales. We examined the variation in small‐scale species richness in a sample of 63 sites from Swedish semi‐natural grasslands, located as fragments in the modem landscape dominated by forest and agricultural land. Data were obtained from two spatial scales at each site. 1 dm2 and 4 m2. Using an analysis based on a Monte Carlo simulation, we found support for the species‐pool hypothesis: a high species richness at the I dm‐ scale was associated with high species richness at the 4 m2 scale. The conclusion from this pattern analysis would, however, be considerably strengthened if we could reduce the likelihood that other mechanisms than sampling from species pools of unequal size influence the pattern of small‐scale species richness. Additional analyses were made in order to identify such mechanisms. We examined whether four putative key traits: seed size, seed production, plant size and reproductive allocation were different among species at comparatively species‐rich vs species‐poor I dm’ plots. We found only a little evidence for such differences. There was a weak tendency that species in the plots with high species richness possessed larger (and fewer) seeds than species from species‐poor plots. Our results are congruent with the main prediction of the species pool model: variation in small‐scale species richness (1 dm2‐ scale) is basically a result of sampling from unequally sized community species pools (4 m2 scale). Variation in species richness between the 4 nr semi‐natural grassland “patches” may thus be sought for among mechanisms operating al larger spatial scales than 4 m2. We briefly discuss such mechanisms, based on other studies performed in the same study area.

Abstract: Individual species may be useful as indicators of biodiversity if an association exists between the presence of a species and another component of biodiversity. We evaluated 40 species of birds and small mammals, including 11 species of conservation concern, as potential indicators of species richness and species composition in southern California coastal sage scrub habitats. This habitat, which is the target of large‐scale conservation planning, has been greatly reduced by human development and supports many plants and animals of conservation concern. We asked whether there is an association between the presence of a potential indicator species and the species richness and composition of the bird or small‐mammal community in which it is found. We used point counts and live‐trapping to quantify the distribution of birds and small mammals, respectively, at 155 points in 16 sites located in three counties. Of the few species we found associated with species richness, some were associated with higher species richness and others with lower richness, and species of conservation concern were not more frequently associated with species richness than were common species. Ordination analysis revealed a geographic gradient in coastal sage scrub bird and small‐mammal species composition across southern California, and 18 of the species we evaluated were associated with the composition of the bird and small‐mammal community in which they were found. Our results suggest that efforts to conserve bird and small‐mammal biodiversity in coastal sage scrub should not focus exclusively on rare species or on locations with the highest species richness, but instead should focus on a diverse suite of species that are representative of the range of variation in communities found in coastal sage scrub habitats.

Plant species richness and composition in managed grasslands: The relative importance of field management and environmental factors

Summary The use of surrogates to identify protected areas is a common practice in conservation biology. The use of top predators as surrogates has been criticized but recently a strong positive relationship was found between the presence of top predators and species diversity of several taxa. As mentioned by the authors, these striking results need to be assessed on a larger scale. We used data from the Swiss Biodiversity Monitoring Programme and the Swiss breeding bird survey to analyse the use of raptor species as a surrogate for plant, butterfly and bird species richness. For each raptor species, we compared species richness in sites where a raptor species was recorded and compared these sites with the remaining sites in which the raptor species was not recorded. For comparison we conducted the same analyses using tits Parus spp. Tits are common prey species of some raptor species and were the most species‐rich generalist genus in our data. We found little justification for a focus on top predators when identifying conservation areas. For bird and plant species richness, raptors were reasonable surrogates for high species richness but no raptor species predicted sites with above‐average butterfly species richness. The presence of tit species performed equally as well as the presence of raptor species to predict sites with high species richness of birds and plants, and performed even better for predicting high butterfly species richness. Synthesis and applications. Conservation planners using indicator species should be aware that relationships among higher taxa are complex and depend on the species group and the scale of analysis. As shown with the case of raptors, the usefulness of a biodiversity indicator can vary between adjacent areas even if the same species groups are analysed. We recommend the use of more than one indicator species from different taxonomic groups when identifying areas of high biodiversity.

Pollinating insect populations, essential for maintaining wild plant diversity and agricultural productivity, rely on (semi)natural habitats. An increasing human population is encroaching upon and deteriorating pollinator habitats. Thus the population persistence of pollinating insects and their associated ecosystem services may depend upon on man-made novel habitats; however, their importance for ecosystem services is barely understood. We tested if man-made infrastructure (railway embankments) in an agricultural landscape establishes novel habitats that support large populations of pollinators (bees, butterflies, hoverflies) when compared to typical habitats for these insects, i.e., semi-natural grasslands. We also identified key environmental factors affecting the species richness and abundance of pollinators on embankments. Species richness and abundance of bees and butterflies were higher for railway embankments than for grasslands. The occurrence of bare (non-vegetated) ground on embankments positively affected bee species richness and abundance, but negatively affected butterfly populations. Species richness and abundance of butterflies positively depended on species richness of native plants on embankments, whereas bee species richness was positively affected by species richness of non-native flowering plants. The density of shrubs on embankments negatively affected the number of bee species and their abundance. Bee and hoverfly species richness were positively related to wood cover in a landscape surrounding embankments. This is the first study showing that railway embankments constitute valuable habitat for the conservation of pollinators in farmland. Specific conservation strategies involving embankments should focus on preventing habitat deterioration due to encroachment of dense shrubs and maintaining grassland vegetation with patches of bare ground.

Grazing is seen as a promising tool to maintain and enhance biodiversity due to the creation of structurally diverse pastures. So far, grassland biodiversity has been studied in relation to various grazing management scenarios, but knowledge of grazing effects gained on experiments managed in the same way over various years is very rare. In the first experiment, we aimed to answer the question of which grazing intensity is suitable to benefit insect diversity. On a long-term grazing experiment two treatments of grazing intensity had been established in 2002, and an additional third treatment had been introduced in 2005. The influence on insect diversity in terms of grasshopper (Orthoptera) and butterfly (Lepidoptera) species richness and abundance was investigated from 2002 to 2004 and again in 2010 and 2011. Confirming our hypotheses, the most intensively grazed paddocks featured the lowest diversity. However, the most extensive treatment did not prove to be more favorable for insects than the medium one. We therefore suggest that continuous grazing of medium intensity is most appropriate to maintain and enhance insect diversity due to a sufficient average sward height and the creation of a patchy grazed sward. This grazing management offers several ecological niches beneficial for a wide array of species, in particular for less mobile herbivore groups like grasshoppers. When focusing grassland phytodiversity, it is also important to consider the type of grazing livestock. Grazer species differ with regard to their grazing behavior and can hence differently affect vegetation and sward structure. In a second experiment, we therefore used either cattle or sheep in mono grazing or both grazer species in mixed grazing. In order to analyze the effect of grazers on different sward types, swards were also manipulated with herbicides against dicotyledonous plants. Paddocks were grazed from 2007 to 2011 and vegetation composition was studied before the grazing season each year and additionally in 2012. Sward composition and diversity confirmed obvious differences between sward types. Grazer species, in contrast, had only negligible effects on vegetation development over years and sward structure. Cattle-grazed paddocks had a higher alpha-(species richness) and beta-diversity, but only for one year and one sward type. As conclusion, in rotational stocking the choice between cattle and/or sheep can only be used in a limited way to form vegetation composition and diversity on common agriculturally used grasslands with a very slight advantage for cattle grazing in terms of phytodiversity. On the same experiment, we also studied how plant species diversity and productivity in terms of herbage mass are related with livestock performance. Our results negated the productivity-diversity theory. Pastures might offer enough plant species for complementary resource use even on species-poor, herbicide treated swards. In contrast, forage of swards with a high species richness contained more crude protein and less ADF thereby leading to a higher nutritive value. However, these results might also be attributed to a legume effect due to the overlap of species richness with legume and forb abundance in this experiment. Pasture productivity and quality were both not influenced by grazer species. Considering all years together, findings point towards an enhanced livestock output on phytodiverse pastures reflected by daily live weight gains of lambs. Mixed grazing also seems promising to contribute to an increased animal performance of lambs and suckler cows. In conclusion, livestock grazing can be used to shape sward structure by the variation of grazing intensity with subsequent effects on biodiversity, whereas the type of livestock seems to have only minor effects, at least in the rotational grazing system studied here. Even though the relationship between species richness and herbage production was not found, a higher amount of dicotyledonous forbs and legumes can contribute to a better forage quality which translates also into higher livestock weight gains of lambs. In conclusion, grassland management can be used to enhance biodiversity and this in turn has the potential to improve livestock performance.

In this study, we aim to evaluate the diversity of vascular plants and lichens coexisting in Artemisia sieberi dominated landscapes of northern Iran. Specifically, we wanted to unveil to what extent Artemisia plant cover and soil features affected species diversity and composition of annuals and lichens growing beneath them, and if annual plants and lichen species were associated at fine spatial scales. The study area was located in Artemisia steppes in North-Eastern Iran. Therefore, four localities dominated by Artemisia sieberi in Golestan National Park and Alagol wetland were selected. We quantified plant and lichen species cover in 5 plots in each location, including 25 subplots and five soil samples to characterize edaphic heterogeneity. Data were analyzed using GLM, NMDS, PERMANOVA, and Mantel Tests. We recorded 19 lichen species, three moss species, and 21 annual plant species in the four localities. Alagol and Alikhani had the most similar lichen compositions and Almeh showed great differences with other sites. However, Bagh and Almeh had the most similar and the most different annual species composition comparing the rest locations, respectively. Location explained 50% and 30% of the variance in lichens and annuals species composition, respectively. Soil chemical properties had no significant influences on lichens and annuals parameters except for Mg content in lichen evenness and clay content on total plant cover. We found a highly significant relationship between the lichen composition and annual plant species composition on fine scale (Mantel r: 0.13; p = 0.0003). The cover of Artemisia explained significant but tiny fractions of lichen species composition (1%) and annual plant species composition (2%) at subplot level. Artemisia steppes of northeastern Iran are not homogeneous habitats and shelter high diversity in lichen and annual plant species. Site location conditions may explain the differences among lichens and annuals compositions.

Comparative biodiversity of insects and mites was studied in organic and conventional farming systems (FS) of tomato at certified organic farming unit of ASPEE College of Horticulture and Forestry (ACHF) and conventional farm of N. M. College of Agriculture (NMCA), Navsari Agricultural University, Navsari, Gujarat during 2018 – 2020, respectively. Total 1016 insect and mite individuals belonging to 9 insect and 1 mite orders, 14 insect and 2 mite families of 20 species of insects and 2 mites were recorded at organic farm (FS) against 967 individuals belonging to 8 insect and 1 mite orders, 13 insect and 2 mite families containing 17 insect and 2 mite species at conventional farm (FS). The diversity of insect and mites was higher in organic as compared to conventional FS. Higher species richness (22), species abundance (1016), species evenness (J= 0.76), species richness index (R= 3.03) and Shannon diversity index (H= 2.36) was observed at organic FS against lower species richness (19), species abundance (967), species evenness (0.69), species richness index (2.62) and Shannon diversity index (2.04) in conventional FS. Insect order Hemiptera and mite order Acarina were more represented at conventional farm (49.63 and 30.50 %) as compared to organic farm (46.99 and 24.17 %). Insects of Coleoptera order were more abundant at organic FS as compared to conventional FS. Relative abundance of herbivores was higher (82.10 %) with lower species evenness (0.71), species richness (1.20) and Shannon diversity index (1.55) in conventional FS as compared to lower relative abundance (69.68 %) with higher species evenness (0.74), species richness (1.37) and Shannon diversity index (1.71) in organic tomato FS. Similarly, 288 insect and mite predators were recorded at organic farm as compared to 161 individuals of insect and mite predators in conventional tomato FS. The relative abundance of predators was higher (28.30 %) with higher species evenness (0.70), species richness (1.59) and Shannon diversity index (1.64) at organic farm whereas, relative abundance (16.55 %), species evenness (0.67), species richness (1.59) and Shannon diversity index (1.64) remained lower at conventional farm. Similarly, higher parasitoids (21), relative abundance (2.02 %), species evenness (0.96), species richness (0.37) and Shannon weiner index (0.67) was observed in organic FS as compared to conventional FS (15, 1.52, 0.91, 0.34 and 0.63). In the present investigation, no pollinators were observed in both the farming systems.

Global warming has been strongly accelerating in the last decades. Climate models tell us that this trend will continue in the future, accompanied by a marked decline in precipitation in Southern Europe, whereas the Alps will likely receive more winter and less summer precipitation. Climate factors and additionally nitrogen deposition and land-use changes have been identified as global change factors posing threats on high-mountain biodiversity, ecosystem stability and services. On the other hand, the characteristic micro-topographic variability of high mountain ecosystems may buffer them against global change impacts. Monitoring data from European mountain peaks show that changes in biodiversity patterns are closely related to rising temperatures. However, the effects of climate change on plant biodiversity differ significantly between temperate and Mediterranean biomes with species richness increases synchronously with warming in the former and richness decreases in the latter. The MediAlps project aimed at disentangling anthropogenic and natural factors underlying differential changes in plant species composition and richness observed on mountain summits in the European Alps and the Mediterranean biome at the local and regional spatial scale. Changes in plant species richness and composition and present land-use impact based on systematic field observations were recorded on long-term monitoring plots on 23 summits. Soil temperature, water potential and local dry nitrogen deposition were measured in situ. Topographic parameters were recorded with photogrammetric methods. At the regional level, climate data and regional nitrogen deposition data from online resources (CHELSA, EMEP) were used and past land-use impact was assessed via guideline-aided semi-structured interviews. (Generalized) linear mixed-effects models and structural equation models (SEM) were employed to assess the impact of these drivers on biodiversity changes. Furthermore, spatio-temporal analyses based on satellite images were conducted. Climate change is and will probably continue to be the main driver of plant biodiversity, species composition and their changes on mountain summits in both biomes. However, there are biome-specific differences with precipitation playing an important role in the Mediterranean biome in addition to temperature, which clearly is the most important single factor in the temperate biome. These changes will likely lead to a further thermophilisation in both biomes. The upwards movement of species from lower elevations will likely also result in a biotic homogenization of the vegetation, exacerbated by the decline of high-elevation endemic species. Species richness will likely continue to increase in the temperate biome until the “pay-off” of extinction debts or threshold effects of population size on extinction risks set in. With decreasing precipitation species richness in the Mediterranean biome will probably decline in the long run, too. Nevertheless, other anthropogenic drivers have to be considered as well, although their influence is arguably much smaller than that of climate variables, namely nitrogen deposition with a negative influence on species richness change in the temperate biome and present land-use with a positive one in the Mediterranean biome. In addition to MediAlps’ main focus on comparing multiple anthropogenic ecological drivers in the Alps with the Mediterranean mountains, the project substantially contributed to a spatially larger scaled long-term observation effort in the frame of the GLORIA (Global Observation Research Initiative in Alpine Environments) program.

Nutrient-poor, dry calcareous grasslands in Central Europe harbour an extraordinary high diversity of plants and invertebrates. Consequently, they are of high conservation value. However, changes in agriculture (intensification or abandonment) have resulted in a dramatic reduction of semi-natural grasslands in the twentieth century. Today, dry grasslands are among the most endangered habitats. Furthermore, these grasslands are frequently fragmented and surrounded by forest or intensively cultivated agricultural areas. Semi-natural grasslands are fragile because their maintenance depends on traditional farming techniques. In order to avoid any loss of species by inappropriate land use, it is important to assess the responses of threatened species to particular types of grassland management. Although different types of present and past pasture management are known to affect the species richness and composition of plant communities, knowledge of the effects on invertebrates is limited. In particular, no studies exist on the influence of different types of pasture management on animals with limited mobility, such as gastropods. In the present thesis, I examined the effects of different pasture management practices on the snail community in dry, nutrient-poor grasslands of the Swiss Jura mountains, where extensive grazing with low stocking rate and without use of fertilizers is a traditional form of grassland management. I assessed the snail communities in extensive pastures grazed by horses, cattle or sheep, in cattle pastures with different management intensity and in extensive pastures with different management history in the last 55 years. Furthermore, gastropod species richness and abundance were examined in transects running from extensive pastures through gradual or abrupt forest edges into the forest interior. Grazing by different livestock species did not affect the species richness, abundance and species composition of land snails. However, independent of livestock species, snail species richness, abundance and number of red-listed species decreased with increasing grazing intensity. Furthermore, cattle pastures without fertilizer application and with low grazing intensity harboured more snail species and more threatened snails than pastures with annual addition of fertilizer and higher grazing intensity. Management intensity had also a negative influence on individual snail species (Cochlicopa lubricella, Truncatellina cylindrica, Vitrina pellucida, Helicella itala and Helix pomatia). Former changes in pasture use for a period of 10–40 years altered the present-day snail fauna. Past shrub cover had a negative effect on the total number of snail species and individuals, the number of open-land species and individuals and the number of red-listed individuals. Former use of fertilizer and higher grazing intensity reduced red-listed species and individuals and altered the snail community. The grassland snail communities of the pastures changed distinctly to forest communities at the first bushes or trees of edges towards forest interior irrespective of the type of forest edge. In pastures, at a distance of 10 m from gradual forest edges, more open-land snail species were found than at the corresponding distance from abrupt forest edges. Furthermore, ecotones of gradual forest edges harboured more open-land individuals than those of abrupt forest edges. For the conservation of grassland land snail communities, it does not matter whether pastures are stocked with horses, cattle or sheep, provided the grazing intensity is low. To preserve the threatened snail species in dry, nutrient-poor grasslands, a network of pastures should be managed without fertilization and grazing intensity should not exceed 180 LU.ha-1.d (product of livestock units per hectare and grazing days). Furthermore, to recover the typical grassland snail community in shrub cleared pastures or former fertilized pastures, the connection between intact pastures and grasslands under restoration should be improved by creating and maintaining new semi-natural areas and by exchanging livestock among these areas during the grazing season. Since shadowing of trees and alterations of the microclimate close to the forest edge may reduce the actual size of small grassland fragments, encroaching shrubs should be regularly removed and gradual forest edges created and maintained.

Intersection reservations as habitats for meadow butterflies and diurnal moths: Guidelines for planning and management

The study was conducted in a montane grassland of Kokosa District, West Arsi Zone of Oromia Region, southern Ethiopia. The objective of the study was to investigate the relationships between aboveground plant biomass and species richness in three farming systems and four grazing management systems. A total of 180 quadrats (each 1 m x 1 m) were sampled in the three farming systems (dominant livestock-enset, enset-livestock and enset-livestock-cereal) and four grazing management systems (communal, enclosure, stream bank and benchmark). All the farming system and grazing management have different management practices. Plant species composition and aboveground plant biomass at different sites were quantified. Altogether 50 plant species (34 grasses, 4 legumes, 3 sedges and 9 forbs) were recorded in the montane grassland of Kokosa District. Even though the majority of the plant species share the different farming systems and grazing management practices, the highest number of species (39) was recorded in the enset-livestock farming system, whereas the lowest (33) species were recorded in the enset- livestock-cereal farming system when all the grazing management and farming systems were combined. Significantly, the highest species richness (4.9 species m-2) was recorded in the enclosure grazing management site whereas the lowest (3.4 species m-2) was recorded in the benchmark grazing site when all grazing sites and farming systems were combined. The relationship between species richness and biomass was detected in the montane grassland. There was significant difference (P &le; 0.05) in species richness for a combination analysis of farming system by grazing management system of the montane grassland. The highest biomass was recorded in the benchmark grazing management sites while the lowest was recorded in the communal grazing sites. On the contrary, maximum species richness was found in the enclosure grazing management sites which had intermediate biomass yield and the lowest species richness was recorded in the benchmark grazing areas with the maximum biomass records. Thus, species richness was observed first to ascend along with biomass increment up to 1932 kg ha-1 and then declined at constant increase of biomass. An increase in biomass in the benchmark grazing sites was not accompanied by an increase in species richness suggesting the dominance of few species in these sites. The rationale behind this might be due to the competitive exclusion of the less competent species from the community at peak biomass production.Keywords: Biomass; Farming System; Grazing Management; Montane Grassland; Species Richness

Background and AimsMediterranean ecosystems have a high vascular plant species richness (SR) relative to their surface area. This SR, representing the balance between speciation and extinction, has been attributed to multiple mechanisms that result in both high rates of speciation and/or low rates of extinction. An abiding question is, however, what is special about Mediterranean ecosystems that enables this high SR? Apart from the long-term climatic stability of the region, SR has also been related to resource availability, the many individuals hypothesis, resource spatial heterogeneity, temporal heterogeneity and biotic feedbacks.MethodsSpatial patterns of species richness were related to climatic, edaphic and biotic variables and to spatial variability within the Greater Cape Floristic Region (GCFR) of South Africa. Boosted regression tree models were used to explore the strength of relationships between SR and environmental predictors related to each hypothesized mechanism.Key ResultsWater availability (i.e. precipitation) was a stronger predictor of SR than potential evapotranspiration or temperature. Scarcity of nutrients was also related to SR. There was no indication that SR was related to the density of individuals and only temporal heterogeneity induced by fire was related to SR. Spatial heterogeneities of climatic, edaphic and biotic variables were strongly associated with SR. Biotic interactions remain difficult to assess, although we have some evidence for a putative role in regulating SR.ConclusionsWhile the lack of ecosystem-resetting disturbances (e.g. glaciation) is undoubtedly a key requirement for high species accumulation, predictably, no one explanation holds the key to understanding SR. In the GCFR high SR is the product of a combination of adequate water, nutrient scarcity, spatial and temporal heterogeneity, and possibly biotic feedbacks.