Butterfly-plant interactions and body size patterns along an elevational gradient in the Manang region of central Nepal

Butterflies are widely studied due to their key ecosystem functions.For this reason,they are used in ecosystem assessment,formulating conservation plans and in raising the environmental awareness.Quantification of different factors affecting diversity of butterflies is important for their effective conservation.In this study,we investigated abiotic and biotic factors affecting species richness and community composition of butterflies along an elevational gradient in Manang region,central Nepal.We also tested if butterfly species follow the Bergmann’s rule.A total of 57 butterfly species belonging to 39 genera and 8 families were recorded in the study area.Out of a total of 127 plant species identified in the study region,only 67 plant species were visited by butterflies as nectar sources.Species richness of butterflies increased with increasing elevation.Species richness was significantly higher in places with shrubs compared to other places and also in autumn than in summer.Species richness of butterflies also depended on composition of plant species occurring at the localities.Butterfly species composition varied among sampling localities.It was also determined by habitat type,elevation,sampling time,plant species and interactions of elevation×time.The relationship between butterfly size and elevation was in the opposite direction than expected according to the Bergmann’s rule.In conclusion,protection of butterfly diversity can only be achieved by protecting different habitats across the diverse physiography of the region and different plant species,in particular herbs and shrubs.Our results do not support the Bergmann’s rule for butterflies along an elevational gradient in our region.

Species traits and shoot-root biomass allocation in 20 dry-grassland species

Aims A plant has a limited amount of resources at any time and it allo-cates them to different structures.in spite of the large number of previous studies on allocation patterns within single species,knowledge of general patterns in species allocation is still very limited.This is because each study was done in different condi-tions using different methodology,making generalization dif-ficult.We investigate intraspecific above-versus below-ground biomass allocation among individuals across a spectrum of dry-grassland plant species at two different developmental stages and ask whether allocation is age-and species specific,and whether differences among species can be explained by their life-history traits and phylogeny.Methods We collected data on above-and below-ground biomass of seedlings and adult plants of 20 species from a common garden experiment.We analysed data on shoot-root biomass allocation allometrically and studied the relationship between the allometric exponents(slopes on log-log scale),species life-history traits and phylogenetic distances.Important Findings We found isometric as well as allometric patterns of biomass alloca-tion in the studied species.Seedlings and adult individuals of more than half of the species differed in their above-versus below-ground biomass allometric exponents.Seedlings and adult individuals of the remaining species differed in their allometric coefficients(inter-cepts).Annual species generally allocated proportionally more to above-than below-ground biomass as seedlings than as adults,whereas perennial species showed the opposite pattern.Plant life-history traits,such as plant life span,age of first flowering,month in which the species begin flowering and specific leaf area were much more important in explaining differences in shoot-root allometry among species than were phylogenetic relationships.This suggests that allocation patterns vary greatly among closely related species but can be predicted based on species life-history traits.

Temperature and precipitation,but not geographic distance,explain genetic relatedness among populations in the perennial grass Festuca rubra

Aims Knowledge of genetic structure of natural populations and its determinants may provide key insights into the ability of species to adapt to novel environments.In many genetic studies,the effects of climate could not be disentangled from the effects of geographic proximity.We aimed to understand the effects of temperature and moisture on genetic diversity of populations and separate these effects from the effects of geographic distance.We also wanted to explore the patterns of distribution of genetic diversity in the system and assess the degree of clonality within the populations.We also checked for possible genome size variation in the system.Methods We studied genetic variation within and among 12 populations of the dominant grass Festuca rubra distributed across a unique regional-scale climatic grid in western Norway,Europe and explored the importance of temperature,precipitation and geo-graphic distance for the observed patterns.We also explored the distribution of genetic diversity within and among popula-tions,identified population differentiation and estimated degree of clonality.The analyses used microsatellites as the genetic marker.The analyses were supplemented by flow cytometry of all the material.Important Findings All the material corresponds to hexaploid cytotype,indicating that ploidy variation does not play any role in the system.The results indicate that temperature and precipitation were better predictors of genetic relatedness of the populations than geographic distance,suggesting that temperature and precipitation may be important determinants of population differentiation.In addition,precipitation,alone and in interaction with temperature,strongly affected population genotypic diversity suggesting increased clonality towards the coldest and especially the coldest wettest climates.At the same time,individuals from the coldest and wettest climates also had the high-est individual genetic diversity,suggesting that only the most hetero-zygous individuals survive under these harsh climates.Most of the genetic variation was distributed within populations,suggesting that most populations have sufficient genetic diversity to adapt to novel climatic conditions.The alpine populations,i.e.populations which are likely the most endangered by climate change,however,lack this potential due to the high levels of clonality as detected in our study.

Genotypic diversity and genotype identity of resident species drive community composition

Aims Species-rich plant communities are more resistant to invasions.In the past decade it was demonstrated that genetic variation also has many ecological effects.In our study we aimed to test whether the patterns of response to the genetic diversity of a resident species differ between colonizing species of different growth forms and whether the response is affected by soil nutrients.Methods We established experimental stands of a common grass,Festuca rubra,harbouring three levels of genetic diversity(1,6 or 18 clonal genotypes,referred to as genotypic diversity)under two soil nutrient levels.In the fourth year after the stands were established,we sowed a mixture of four colonizers into the stands:a stoloniferous legume(Trifolium repens),a broad-leaf tussock grass(Anthoxanthum odoratum),a largerosette forb(Plantago lanceolata)and a small-rosette forb(Campanula rotundifolia).We observed species establishment and growth over 3 years.We tested whether colonization success depended on genotypic diversity,specific Festuca genotypes,soil nutrients and colonizer growth form.Important Findings The colonization success and biomass of the colonizers were significantly affected by the genotypic diversity and the genotype identity of the resident clonal grass.The response,however,differed between the colonizers.The strongest response to the genotypic diversity of the resident species was observed in the tussock grass with a growth form and architecture similar to the resident species.The large-rosette species responded in early stages of growth whereas the stoloniferous legume did not respond at all.The intraspecific genotypic diversity and genotype identity of the resident species play an important role in the assembly of plant communities.