Patterns of pollination interactions at the community level are related to the type and quantity of floral resources

1. A fundamental question in community ecology is how the quantity of floral resources affects pollinator activity and how this relates to the structure and robustness of pollination networks. The issue has been mainly addressed at the species level, while at the community level several questions are still open. 2. Using a species-rich semi-natural grassland as model ecosystem, we explored the relationship between community-level quantity of floral resources, the number of flower visits at community level and descriptors of the structure and robustness of pollination networks. To assess whether patterns of pollination interactions were consistent when using different types of floral resources, we measured three types of floral resources, namely the volume of nectar, the number of pollen grains and the number of flowers. 3. Community-level pollinator visitation rate showed a hump-shaped relationship with the quantity of floral resources. Results were consistent among models employing different measures of floral resources as independent variables. The relationship between the quantity of floral resources and the structure and robustness of the network was not consistent among different types of floral resources; only intermediate levels of nectar volume were associated with high levels of network robustness. 4. The pattern we found is in contrast with some former studies which reported positive linear relationships between the community-level visitation rate of pollinators and the quantity of floral resources. Rather, the observed hump-shaped pattern resembles the relationship previously found between the quantity of floral resources of a given plant species and its visitation rate per flower. Our results highlighted that, by using specific types of floral resources (e.g. the volume of nectar and the number of pollen grains), it is possible to reveal ecological processes that would be masked by using the number of flowers as the sole measure of floral resource

Factors affecting reproductive success in three entomophilous orchid species in Hungary

The reproductive success of orchids is traditionally estimated by determining the fruit-set of individuals. Here, we investigated both the fruit and the seed production of three orchid species and the factors that may affect individual fruit-set, like pollination strategy, individual traits or the annual amount of precipitation. The species [Dactylorhiza sambucina (L.) Soó, Dactylorhiza majalis (Rchb.) P. F. Hunt & Summerhayes and Platanthera bifolia (L.) L. C. M. Richard] were studied in three consecutive years (2010–2012) in the Bükk Mountains, Hungary. All three species were proved to be non-autogamous by a bagging experiment. Data analyses showed significant differences between seed numbers but not between fruit-sets of species. There was no statistical difference in individual reproductive success between wet and dry years, however, the effect of the annual amount of precipitation is significant on the population level. Comparison of published fruit-set data revealed accordance with our results in P. bifolia, but not in D. sambucina and D. majalis. We assume that the surprisingly high fruit-set values of the two Dactylorhiza species may be due to the fact that the pollination crisis reported from Western European countries is not an actual problem in the Bükk Mountains, Hungary

Vegetation type and grazing intensity jointly shape grazing effects on grassland biodiversity

LBL

Analysis of factors of effects on venison as food raw material (a pleriminary study)

In Hungary, approximately 200-250 thousand big game animals are hunted annually. Animals are not only hunted for valuable trophies, but also for thousands of tons of venison for consumption. A major part of this is sold abroad, bypassing the Hungarian market. It can be said in general that venison is low in fat and carbohydrate and rich in protein, micro- and macro elements, as well as vitamins. Currently in Hungary, venison is produced in free ranging areas, game preserves and game farms. There are significant differences between them in terms of environmental conditions and the employed keeping and feeding technologies. Impacts of these factors on the meat quality are well-known in domestic animals, but they are only partially understood in game species. The quality of red deer venison, the influential factors and risks have been examined in the current project. Red deer venison has been acquired from free ranging areas, game preserves and game farms. Changes in the volume of venison in Hungary and its distribution between game species were estimated, as well as the tendency in the number of game preserves and game farms was shown in this study. In Hungary, the quantity of hunted game species was approximately 10.000 tons in 2010, from which wild boar and red deer were the most abundant. We expect it to be the same in the future

Is seasonal diet composition of red deer (Cervus elaphus) is affected by game preservation?

In Europe, approx. 280,000 deer, predominantly red deer (Cervus elaphus) and fallow deer (Dama dama) were kept in game preserves in 2012. Information on foraging habits of fenced populations is important for wildlife management purposes. However, actual knowledge of diet composition of red deer is mainly based on studies of free-ranging deer. Until this time, few specific studies have compared the diet composition of deer living in fenced and unfenced areas. Hence, we aimed to compare how diet composition differs inside and outside a game preserve during the vegetation period. Botanical composition of red deer diet was studied in fenced and unfenced areas of a forested region in Gyarmatpuszta, Hungary. We collected faeces samples in spring, summer and autumn (n=20 for each area and period). Analyses were made by microhistological identification of plant epidermis fragments found in the faeces. Browse species dominated the diet of red deer (40-82%) both, in the fenced and unfenced areas throughout the vegetation period. Oak species (Quercus spp.), the common tree of the areas, were always the dominant browse species in the diet (11-53%). The consumption of different shrub species was much lower in the fenced than in unfenced area. Ash (Fraxinus spp.), bramble (Rubus spp.), black locust (Robinia pseudoacacia), dogwood (Cornus sanguinea) or rose (Rosa spp.) were highly selected by some individuals (15-86%). In turn, supplementary food appeared in a higher proportion in red deer diet in the game preserve than outside. This consumption was dominated by corn in fenced area in summer (21±33%) and autumn (35±14,8%). Grasses and forbs did not exceed 10% of the diet in the most cases. Differences in the diet composition can influence the quality of the individuals (body mass, trophy and venison quality) determining the management success in game preserves. Ongoing and later nutritional analyses of consumed plant materials and venison can reveal such differences

A gímszarvas táplálékának összehasonlítása egy vadaskertben és környékén.

Red deer (Cervus elaphus) is a widespread game species in Hungary. The intensive rate of population growth can result a strong degradation of the natural vegetation. In the forested areas serious damage can occur when the main food sources of deer, the available browse species, are lacking or scarce. In the preserves the density of deer can be quite high occasionally, ensuring hunting possibilities and venison production. Since the regeneration of the browse species is restricted by deer, the role of supplementary feeding (hay-silage, grain, special supplements etc.) could be particularly important. Knowledge of red deer diet is mainly based on data of free-ranging deer. However, information on food habits of fenced populations is also important for wildlife management purposes. So far, few specific studies have compared the diet composition of deer living in fenced and unfenced areas. We aimed to compare the diet composition of free living populations with fenced ones during the vegetation period to promote the wildlife management in such a special environment. We collected faeces samples in a preserve and in the neighbouring similar unfenced habitat in spring, summer and autumn (n=20 for each area and period). Analyses were made by microhistological identification of plant epidermis fragments found in the individual faeces. Browse species dominated the deer diet (40-82%) both in the fenced and unfenced areas throughout the vegetation period. Grasses and forbs did not exceed 10% in most cases. Deer consumed mainly oak and acorn, or oak and supplemental corn in the preserve while 4 to 6 species made up the great mass of the diet outside the fences. Only a few individuals consumed the supplementary forage items other than corn in great amount, but most of deer did not eat any of the supplements.The summer diet was more diverse and even in the unfenced area, and more forage items were consumed than in the fenced area. We conclude that the preserves could be unfavourable for red deer. When the natural food resources are largely absent, deer could be forced to feed on litter, or supplementary feed should meet their requirements

The importance of dispersal and species establishment in vegetation dynamics and resilience

Editorial of the Special Feature 'Dispersal and Establishment'

Cultural heritage and biodiversity conservation - plant introduction and practical restoration on ancient burial mounds

K