2014. szeptember 2., kedd

Deák et al. (2014) Tuexenia


Abstract
Wet meadows are transitional habitats between wetlands and dry-mesophilous grasslands; thus, they are vital in sustaining biodiversity as sources, stepping stones and green corridors of species dispersal. It is especially valid for inland alkali vegetation, where high landscape-scale patchiness is typical and rapid shifts between vegetation types occur frequently. Solonetz meadows (Beckmannion eruciformis) are among the best-preserved open habitats in Europe harbouring a unique flora including several endemics. Besides their importance, studies on the vegetation of solonetz meadows are scarce even though this knowledge would be vital for their effective conservation and management. Using own records and literature data, we provide a synthesis of the alliance Beckmannion eruciformis to charac-terise its associations floristically and ecologically in five regions along the river Tisza, East Hungary. We studied three associations of the alliance: (i) Agrostio stoloniferae-Alopecuretum pratensis, (ii) Agrostio stoloniferae-Beckmannietum eruciformis and (iii) Agrostio stoloniferae-Glycerietum pedi-cellatae. We found that solonetz meadow associations were separated along a moisture gradient with Agrostio stoloniferae-Alopecuretum pratensis at the drier end and Agrostio stoloniferae-Glycerietum pedicellateae at the wet end. This gradient was also justified by the distribution of the phytosociological groups. The proportion of species of Festuco-Brometea division was the highest in Agrostio stolonifer-ae-Alopecuretum pratensis, while the proportion of Cypero-Phragmitetea species was the highest in Agrostio stoloniferae-Glycerietum pedicellateae. Species of Puccinellio-Salicornetea had the highest proportion in Agrostio stoloniferae-Beckmannietum eruciformis, indicating the high soil salinity of this association. Our results suggest that Agrostio stoloniferae-Alopecuretum pratensis association plays an important role in preserving the continental flora elements of the surrounding dry grasslands. The ecological indicator values for soil moisture and salinity suggest that in case of the studied solonetz meadow associations, humidity increases with decreasing elevation, while salinity is highest at medium elevations. Our results suggest that Agrostio stoloniferae-Beckmannietum eruciformis is a transition towards salt marsh associations, while Agrostio stoloniferae-Glycerietum pedicellatae is a transition towards freshwater marshes. Our results show that preserving solonetz meadows is an important task for nature conservation as they have a crucial role in maintaining landscape-scale species and habitat diversity and act as buffer zones around wetlands.

Keywords
alkali grasslands, Festuco-Puccinellietea, hay-meadows, landscape-scale diversity, mois-ture gradient, salinity gradient

Biró et al. (2015) Applied Ecology and Environmental Research


Abstract
Honeybees are the most numerous and significant among insect pollinators, but despite their significance their potential role in increasing the reproductive success of threatened European orchids remains largely unexplored. In this study we aim to evaluate the effect of apiary proximity on the fructification rate of the rare and endangered Adriatic Lizard Orchid (Himantoglossum adriaticum H. Baumann). To do so, first we quantified the reproductive success (fruit set) of the Adriatic Lizard Orchids in a Hungarian population in close proximity to a honeybee apiary at Nagytevel. Then we compared the reproductive success in this population to the reproductive success in 3 other Hungarian, 4 Croatian populations (observed during the same year, 2013) and further 4 populations from Hungary (studied in previous years, 1992–2011) with no apiaries in the close proximity of these. The realised 61.7 % fruit set at Nagytevel is the highest reproductive success ever recorded for this species. The importance of apiaries is further emphasised by the fact that the reproductive success of Lizard Orchid individuals decreased significantly with increasing distance from the apiary. Our results provide empirical support for the conservation importance of apiculture and suggests promising results for practical application of apiaries in the conservation of of deceptively pollinated orchids characterised by lower fruit set (e.g. Orchis, Anacamptis, Himantoglossum).

Keywords
apiculture, fruit set, Himantoglossum adriaticum, pollination crisis, Orchidaceae

Zhang et al. (2014) Pest Management Science


Abstract
BACKGROUND: The two common whitefly species, Bemisia tabaci (Gennadius) MEAM1 and Trialeurodes vaporariorum (Westwood), often co-occur on their host plants. The effect of host plant occupation by one species on later-arriving conspecific individuals or on the other competing species was examined. RESULTS: Resource preoccupied by T. vaporariorum had mostly negative effects on the life history parameters of later-arriving conspecifics. Red-eyed nymph and immature survival of T. vaporariorum decreased when resource was preoccupied by conspecifics, irrespective of the previous occupation scenario. However, resource preoccupied by T. vaporariorum had only minor detrimental effectsonthe performance of later-arriving B. tabaci MEAM1.In theopposite colonisation sequence, previous occupation by B. tabaci MEAM1 had no significant effects on the life history parameters of later-arriving conspecifics, but severe detrimental effects were observed on the performance of later-arriving T. vaporariorum. Total immature survival of T. vaporariorum decreased in both weak and strong previous occupation situations by B. tabaci MEAM1. CONCLUSION: The interspecific interactions between B. tabaci MEAM1 and T. vaporariorum were asymmetric, with B. tabaci MEAM1 being the superior competitor. This superiority could partially explain the rapid spread of B. tabaci MEAM1 in China.


Keywords
Bemisia tabaci, cryptic species, MEAM1, asymmetric competition, interspecific interaction, resource previous occupation, Trialeurodes vaporariorum

Gilioli et al. (2014) Science of the Total Environment


Abstract
The current methods to assess the environmental impacts of plant pests differ in their approaches and there is a lack of the standardized procedures necessary to provide accurate and consistent results, demonstrating the complexity of developing a commonly accepted scheme for this purpose. By including both the structural and functional components of the environment threatened by invasive alien species (IAS), in particular plant pests, we propose an environmental risk assessment scheme that addresses this complexity. Structural components are investigated by evaluating the impacts of the plant pest on genetic, species and landscape diversity. Functional components are evaluated by estimating how plant pests modify ecosystem services in order to determine the extent to which an IAS changes the functional traits that influence ecosystem services. A scenario study at a defined spatial and temporal resolution is then used to explore how an IAS, as an exogenous driving force, may trigger modifications in the target environment. The method presented here provides a standardized approach to generate comparable and reproducible results for environmental risk assessment as a component of Pest Risk Analysis. The method enables the assessment of overall environmental risk which integrates the impacts on different components of the environment and their probabilities of occurrence. The application of the proposed scheme is illustrated by evaluating the environmental impacts of the invasive citrus long-horn beetle, Anoplophora chinensis. 

Keywords
Environmental risk, Plant pests, Invasive alien species (IAS), Ecosystem services, Functional biodiversity, Service-providing units

Zhang et al. (2014) Journal of Integrative Agriculture

Zhang X-M, Yang N-W, Wan F-H, Lövei GL (2014): Density and seasonal dynamics of Bemisia tabaci (Gennadius) Mediterranean on common crops and weeds around cotton fields in Northern China. Journal of Integrative Agriculture 13: 2211-2220. DOI:10.1016/S2095-3119(13)60613-9

Abstract 
BACKGROUND: The two common whitefly species, Bemisia tabaci (Gennadius) MEAM1 and Trialeurodes vaporariorum (Westwood) often co-occur on their host plants. We examined the effect of host plant occupation by one species on later arriving conspecific individuals or on the other competing species.
RESULTS: Resource pre-occupied by T. vaporariorum had mostly negative effects on the life history parameters of later-arriving conspecifics. Red-eyed nymph and immature survival of T. vaporariorum decreased when resource was pre-occupied by conspecifics, irrespective of the previous occupation scenario. However, resource pre-occupied by T. vaporariorum had only minor detrimental effects on the performance of later-arriving B. tabaci MEAM1. In the opposite colonization sequence, previous occupation by B. tabaci MEAM1 had no significant effects on life history parameters of later-arriving conspecifics, but severe detrimental effects were observed on the performance of later-arriving T. vaporariorum. Total immature survival of T. vaporariorum decreased in both weak and strong previous occupation situations by B. tabaci MEAM1.
CONCLUSION: The interspecific interactions between B. tabaci MEAM1 and T. vaporariorum were asymmetric, with B. tabaci MEAM1 being the superior competitor. This superiority could partially explain the rapid spread of B. tabaci MEAM1 in China

Keywords
Bemisia tabaci, cryptic species, MEAM1, asymmetric competition, interspecific interaction, resource previous occupation, Trialeurodes vaporariorum