The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Ulrich Zumkier - One of the best experts on this subject based on the ideXlab platform.
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large scale monitoring of effects of clothianidin dressed oilseed rape seeds on Pollinating Insects in northern germany effects on red mason bees osmia bicornis
Ecotoxicology, 2016Co-Authors: Britta Peters, Ulrich ZumkierAbstract:The aim of this study was to investigate the effects of Elado® (10 g clothianidin & 2 g beta-cyfluthrin/kg seed)-dressed oilseed rape on the development and reproduction of mason bees (Osmia bicornis) as part of a large-scale monitoring field study in Northern Germany, where oilseed rape is usually cultivated at 25–33 % of the arable land. Both reference and test sites comprised 65 km2 in which no other crops attractive to Pollinating Insects were present. Six study locations were selected per site and three nesting shelters were placed at each location. Of these locations, three locations were directly adjacent to oilseed rape fields, while the other three locations were situated 100 m distant from the nearest oilseed rape field. At each location, 1500 cocoons of O. bicornis were placed into the central nesting shelter. During the exposure phase, nest building activities and foraging behaviour were assessed repeatedly. Cocoons were harvested in autumn to assess parasitization and reproduction including larval development. The following spring, the emergence of the next generation of adults from cocoons was monitored. High reproductive output and low parasitization rates indicated that Elado®-dressed oilseed rape did not cause any detrimental effects on the development or reproduction of mason bees.
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large scale monitoring of effects of clothianidin dressed osr seeds on Pollinating Insects in northern germany effects on large earth bumble bees bombus terrestris
Ecotoxicology, 2016Co-Authors: Guido Sterk, Britta Peters, Ulrich ZumkierAbstract:The aim of this study was to investigate the effects of Elado®-dressed winter oilseed rape (OSR, 10 g clothianidin & 2 g beta-cyfluthrin/kg seed) on the development, reproduction and behaviour of large earth bumble bees (Bombus terrestris) as part of a large-scale monitoring field study in Northern Germany, where OSR is usually cultivated at 25–33 % of the arable land. Both reference and test sites comprised 65 km2 in which no other crops attractive to Pollinating Insects were present. Six study locations were selected per site and 10 bumble bee hives were placed at each location. At each site, three locations were directly adjacent to OSR fields and three locations were situated 400 m distant from the nearest OSR field. The development of colonies was monitored from the beginning of OSR flowering in April until June 2014. Pollen from returning foragers was analysed for its composition. An average of 44 % of OSR pollen was found in pollen loads of bumble bees indicating that OSR was a major resource for the colonies. At the end of OSR flowering, hives were transferred to a nature reserve until the end of the study. Colony development in terms of hive weight and the number of workers showed a typical course with no statistically significant differences between the sites. Reproductive output was comparatively high and not negatively affected by the exposure to treated OSR. In summary, Elado®-dressed OSR did not cause any detrimental effects on the development or reproduction of bumble bee colonies.
Britta Peters - One of the best experts on this subject based on the ideXlab platform.
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large scale monitoring of effects of clothianidin dressed oilseed rape seeds on Pollinating Insects in northern germany effects on red mason bees osmia bicornis
Ecotoxicology, 2016Co-Authors: Britta Peters, Ulrich ZumkierAbstract:The aim of this study was to investigate the effects of Elado® (10 g clothianidin & 2 g beta-cyfluthrin/kg seed)-dressed oilseed rape on the development and reproduction of mason bees (Osmia bicornis) as part of a large-scale monitoring field study in Northern Germany, where oilseed rape is usually cultivated at 25–33 % of the arable land. Both reference and test sites comprised 65 km2 in which no other crops attractive to Pollinating Insects were present. Six study locations were selected per site and three nesting shelters were placed at each location. Of these locations, three locations were directly adjacent to oilseed rape fields, while the other three locations were situated 100 m distant from the nearest oilseed rape field. At each location, 1500 cocoons of O. bicornis were placed into the central nesting shelter. During the exposure phase, nest building activities and foraging behaviour were assessed repeatedly. Cocoons were harvested in autumn to assess parasitization and reproduction including larval development. The following spring, the emergence of the next generation of adults from cocoons was monitored. High reproductive output and low parasitization rates indicated that Elado®-dressed oilseed rape did not cause any detrimental effects on the development or reproduction of mason bees.
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large scale monitoring of effects of clothianidin dressed osr seeds on Pollinating Insects in northern germany effects on large earth bumble bees bombus terrestris
Ecotoxicology, 2016Co-Authors: Guido Sterk, Britta Peters, Ulrich ZumkierAbstract:The aim of this study was to investigate the effects of Elado®-dressed winter oilseed rape (OSR, 10 g clothianidin & 2 g beta-cyfluthrin/kg seed) on the development, reproduction and behaviour of large earth bumble bees (Bombus terrestris) as part of a large-scale monitoring field study in Northern Germany, where OSR is usually cultivated at 25–33 % of the arable land. Both reference and test sites comprised 65 km2 in which no other crops attractive to Pollinating Insects were present. Six study locations were selected per site and 10 bumble bee hives were placed at each location. At each site, three locations were directly adjacent to OSR fields and three locations were situated 400 m distant from the nearest OSR field. The development of colonies was monitored from the beginning of OSR flowering in April until June 2014. Pollen from returning foragers was analysed for its composition. An average of 44 % of OSR pollen was found in pollen loads of bumble bees indicating that OSR was a major resource for the colonies. At the end of OSR flowering, hives were transferred to a nature reserve until the end of the study. Colony development in terms of hive weight and the number of workers showed a typical course with no statistically significant differences between the sites. Reproductive output was comparatively high and not negatively affected by the exposure to treated OSR. In summary, Elado®-dressed OSR did not cause any detrimental effects on the development or reproduction of bumble bee colonies.
Katrin Born - One of the best experts on this subject based on the ideXlab platform.
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Large-scale monitoring of effects of clothianidin dressed oilseed rape seeds on Pollinating Insects in Northern Germany: implementation of the monitoring project and its representativeness
Ecotoxicology, 2016Co-Authors: Fred Heimbach, Anja Russ, Maren Schimmer, Katrin BornAbstract:Monitoring studies at the landscape level are complex, expensive and difficult to conduct. Many aspects have to be considered to avoid confounding effects which is probably the reason why they are not regularly performed in the context of risk assessments of plant protection products to Pollinating Insects. However, if conducted appropriately their contribution is most valuable. In this paper we identify the requirements of a large-scale monitoring study for the assessment of side-effects of clothianidin seed-treated winter oilseed rape on three species of Pollinating Insects ( Apis mellifera , Bombus terrestris and Osmia bicornis ) and present how these requirements were implemented. Two circular study sites were delineated next to each other in northeast Germany and comprised almost 65 km^2 each. At the reference site, study fields were drilled with clothianidin-free OSR seeds while at the test site the oilseed rape seeds contained a coating with 10 g clothianidin and 2 g beta-cyfluthrin per kg seeds (Elado®). The comparison of environmental conditions at the study sites indicated that they are as similar as possible in terms of climate, soil, land use, history and current practice of agriculture as well as in availability of oilseed rape and non-crop bee forage. Accordingly, local environmental conditions were considered not to have had any confounding effect on the results of the monitoring of the bee species. Furthermore, the study area was found to be representative for other oilseed rape cultivation regions in Europe.
Rodolfo Dirzo - One of the best experts on this subject based on the ideXlab platform.
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effects of fragmentation on pollinator abundance and fruit set of an abundant understory palm in a mexican tropical forest
Biological Conservation, 2008Co-Authors: Armando Aguirre, Rodolfo DirzoAbstract:Abstract Tropical forest fragmentation affects both biodiversity and plant reproductive success when small, isolated fragments sustain a reduced diversity or abundance of pollinators. Fragmentation-related effects have been poorly investigated in the case of palms, an important structural and functional component of tropical forests. We examined the relationships between fragment size and diversity and abundance of flower visitors, and palm reproduction, by quantifying the arthropod fauna associated to inflorescences of the palm Astrocaryum mexicanum, and its fruit set, in fragments of different size. The sample yielded a total of 228,772 arthropods (10 orders, 60 species). Coleoptera was the predominant group (⩾50% of the species), followed by Hymenoptera (20%), while the remaining (30%) was distributed among the other eight orders. We found a predominance of Pollinating Insects (Coleoptera-Nitidulidae), representing 85% of all visitors. Pollinator abundance was negatively affected by fragmentation, with a 4.2-fold average difference between small (
Fred Heimbach - One of the best experts on this subject based on the ideXlab platform.
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Large-scale monitoring of effects of clothianidin dressed oilseed rape seeds on Pollinating Insects in Northern Germany: implementation of the monitoring project and its representativeness
Ecotoxicology, 2016Co-Authors: Fred Heimbach, Anja Russ, Maren Schimmer, Katrin BornAbstract:Monitoring studies at the landscape level are complex, expensive and difficult to conduct. Many aspects have to be considered to avoid confounding effects which is probably the reason why they are not regularly performed in the context of risk assessments of plant protection products to Pollinating Insects. However, if conducted appropriately their contribution is most valuable. In this paper we identify the requirements of a large-scale monitoring study for the assessment of side-effects of clothianidin seed-treated winter oilseed rape on three species of Pollinating Insects ( Apis mellifera , Bombus terrestris and Osmia bicornis ) and present how these requirements were implemented. Two circular study sites were delineated next to each other in northeast Germany and comprised almost 65 km^2 each. At the reference site, study fields were drilled with clothianidin-free OSR seeds while at the test site the oilseed rape seeds contained a coating with 10 g clothianidin and 2 g beta-cyfluthrin per kg seeds (Elado®). The comparison of environmental conditions at the study sites indicated that they are as similar as possible in terms of climate, soil, land use, history and current practice of agriculture as well as in availability of oilseed rape and non-crop bee forage. Accordingly, local environmental conditions were considered not to have had any confounding effect on the results of the monitoring of the bee species. Furthermore, the study area was found to be representative for other oilseed rape cultivation regions in Europe.