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Auteur Harald Albrecht |
Documents disponibles écrits par cet auteur (8)
Affiner la rechercheCan rare arable plants benefit biological pest control potential of cereal aphids in croplands? / Alina Twerski in Basic and applied ecology, Online (12 December 2022)
Titre : Can rare arable plants benefit biological pest control potential of cereal aphids in croplands? Type de document : Imprimé Auteurs : Alina Twerski ; Harald Albrecht ; Róbert Gallé ; Fabian Sauter ; Péter Császár ; Christina Fischer Année de publication : 2022 Article en page(s) : 1-46 Langues : Anglais (eng) Catégories : [CBNPMP-Thématique] Messicole Résumé : In agricultural landscapes, arable plants are negatively affected by management intensification. These species can fulfill various ecosystem functions, such as biological pest control, by supporting predators. The ecosystem functions of common plant species are widely known. By contrast, the contribution of rare arable plants (RAPs) to biocontrol in cereal fields remains poorly understood. This study investigated the effect of RAPs on biocontrol potential. We compared cropped plots with and without sowing of rare and threatened arable plant species and investigated the effects on cereal aphids and their antagonistic predators, active hunting, and web-building spiders, as well as carnivorous/omnivorous carabids. We counted the total number of aphids on cereal shoots and trapped ground-dwelling arthropods on an experimental field and on 10 agricultural farms in the vicinity of Munich, Germany, in 2018 and 2019. The effects of the presence of RAP were analyzed using linear mixed-effect models, whereas cover of RAPs was analyzed using structural equation models. Linear models revealed that the presence of RAPs did not significantly affect the aphid density and the activity densities of spiders and carabids. Structural equation models revealed direct negative effects of RAP cover on aphid density. However, no indirect effects via the predators of aphids were detected. Direct negative effects of active hunting spiders on aphids were determined, but not of the other potential predators. The weak impact of RAPs on spiders and carabids suggests that the species richness of plant communities exerts only little influence on organisms at higher trophic levels. Our results suggest that RAPs may indirectly impact aphid infestation, however, the activity density of spiders and carabids were unsuitable indicators for such interactions. Lien pérenne : DOI : 10.1016/j.baae.2022.12.003 Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=148564
in Basic and applied ecology > Online (12 December 2022) . - 1-46Twerski, Alina, Albrecht, Harald, Gallé, Róbert, Sauter, Fabian, Császár, Péter, Fischer, Christina 2022 Can rare arable plants benefit biological pest control potential of cereal aphids in croplands? Basic and applied ecology, Online: 1-46.Documents numériques
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est un extrait de Proceedings 9th EWRS Symposium, Budapest 1995. Challenges for Weed Science in a Changing Europe (1995)
Titre : Changes in the arable weed flora of Germany during the last five decades Type de document : Extrait d'ouvrage Auteurs : Harald Albrecht Année de publication : 1995 Importance : p. 41-48 Langues : Anglais (eng) Catégories : [CBNPMP-Thématique] Messicole Résumé : A whole string of investigations recently described the changes in the agrestal weed flora of different German regions during the last five decades. The present paper summarizes and evaluates the results of these reports. Most of the publications dealing with the change in the average number of weed species found a decline of between 50 to 90 %. Only on barren soils with a sandy texture, which were formerly characterized by low numbers of weed species, the intensified use of fertilizers occasionally caused a rise in variety. Of 203 species, the development of which was mentioned in at last two publications, 120 decreased in occurence (= 59 %), 58 stayed on a constant level (= 29 %) and 25 species (= 12 %) were found more often. Dicotyledoneous plants, cereal weeds, and indicators for calcerous and acid soils were particularly affected by the decline. Another group of taxa which today show considerably lower frequency in fields than in the middle of the century comprises plants mainly occurring in grassland communities. In contrast, where monocotyledoneous and nitropilic plants as well as root crop weeds are concerned, a constant to increasing tendency was observed. Of the species registered in the present survey, 35 are mentioned in the red data books for the eastern and western part of Germany. 27 of them decreased, 6 showed no significant change and 2 species increased in frequency. The development of the weed flora during the last decades has its roots in farreaching changes in arable farming practice. Modifications in the choice of crops, in rotations, chemical and mechanical weed control, fertilizing, soil management, sowing time and technique, purification of seed and land consolidation are reasons for this process. Due to strong interactions between all these components, it is impossible to reconstruct the influence of every single factor on the change of the agrestal weed flora in Germany during the last decades. Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=85639 Albrecht, Harald 1995 Changes in the arable weed flora of Germany during the last five decades. In: Proceedings 9th EWRS Symposium, Budapest 1995. Challenges for Weed Science in a Changing Europe. : 41-48.Documents numériques
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Chapitre (1995)Adobe Acrobat PDF
Titre : Development of the arable vegetation 23 years after conversion from conventional to organic farming – experiences from a farm-scale case study in southern Germany Type de document : Imprimé Auteurs : Harald Albrecht ; Sandra Mademann ; Helmut Weikl Année de publication : 2020 Article en page(s) : 291-308 Langues : Anglais (eng) Catégories : [CBNPMP-Thématique] Messicole Résumé : Recent meta-analyses assessing the impact of organic farming on plant species diversity showed that positive effects mainly occurred at a small scale while benefits at the farm or landscape level were less pronounced. The studies also detected that common species were more favored by organic farming than rare ones. In a farm scale study in southern Bavaria, Germany, we analyzed how the conversion to organic farming changed arable plant communities over a 23-years period and questioned the impact on weed management and species conservation. Vegetation sampling started two years before this conver-sion. At the end of the study period, crop cover had slightly decreased but yields of winter cereals (5.2 t/ha) still achieved 78% of the pre-organic harvest. Arable plant cover increased from 2 to 40% and the soil seed banks enlarged from 4200 to 33,300 seeds m-². Total numbers of plant species increased by 46% at the plot level and by 22% at the farm level, plant species characteristic of arable fields in-creased by 50% and 19%, respectively. Populations of both threatened and problematic plant species clearly profited from the conversion. Our results generally confirm that organic farming benefits plant biodiversity in arable land. Such benefits being more pronounced at the plot scale verifies previous studies, however, these effects were also visible over the whole arable area of the farm. A significant increase in the cover of insect-pollinated plants indicated that organic management can also support ecosystem functions. Our data prove that long-term organic farming can increase nature conservation value of the arable flora with only a moderate setback of crop yields. Lien pérenne : DOI : 10.14471/2020.40.005 Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=148429
in Tuexenia > 40 (2020) . - 291-308Albrecht, Harald, Mademann, Sandra, Weikl, Helmut 2020 Development of the arable vegetation 23 years after conversion from conventional to organic farming – experiences from a farm-scale case study in southern Germany. Tuexenia, 40: 291-308.Documents numériques
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Article (2020)URLFloristic diversity at the habitat scale in agricultural landscapes of Central Europe - summary, conclusions and perspectives / Rainer Waldhardt (2003)
est un tiré à part de 98 (1-3) - September 2003 - Biotic indicators for biodiversity and sustainable agriculture (Agriculture, ecosystems & environment)
Titre : Floristic diversity at the habitat scale in agricultural landscapes of Central Europe - summary, conclusions and perspectives Type de document : Tiré à part de revue Auteurs : Rainer Waldhardt (1961-) ; Dietmar Simmering ; Harald Albrecht Année de publication : 2003 Importance : 79 - 85 Langues : Anglais (eng) Catégories : [CBNPMP-Thématique] Biodiversité, niveau de perception
[CBNPMP-Thématique] Terres agricoles et paysages artificielsRésumé : Referring to the agricultural history in Central Europe determinants of floristic diversity at the habitat scale and the decline in diversity over the last few decades are described. In this context the preservation of floristic diversity is stressed to be one important goal of modern, multifunctional agricultural land use. To reach this goal indicators of diversity are useful tools to evaluate the effects management practices have on floristic diversity in agro-ecosystems. However, “key indicators” that allow an easy assessment and evaluation of diversity are still lacking. Potentially, indicators of biodiversity measures at the habitat scale can be developed from a large number of parameters. An attempt to classify parameters into three major types of indicators and requirements indicators have to meet are presented. Based on the contributions in this special issue and further references recent approaches to indicate floristic diversity at the habitat scale in agricultural landscapes of Central Europe are summarized and discussed. It is concluded that further research should focus on the validation of existing approaches and their integration into a comprehensive set of indicators and on the development of standardized modes of collection for data. Lien pérenne : DOI : 10.1016/S0167-8809(03)00071-9 Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=134224 Waldhardt, Rainer (1961-), Simmering, Dietmar, Albrecht, Harald 2003 Floristic diversity at the habitat scale in agricultural landscapes of Central Europe - summary, conclusions and perspectives. Agriculture, ecosystems & environment, 98(1-3) : 79 - 85.Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 22116 JC Tiré à part Bureaux Conservation Consultable
Titre : Management options for the conservation of rare arable plants in Europe Type de document : Tiré à part de revue Auteurs : Harald Albrecht ; Jocelyne Cambecèdes ; Marion Lang ; Markus Wagner Année de publication : 2016 Langues : Anglais (eng) Catégories : [CBNPMP-Thématique] Conservation et gestion des espèces
[CBNPMP-Thématique] Mauvaises herbes
[CBNPMP-Thématique] MessicoleRésumé : Rapid intensification of farming after 1950 resulted in a dramatic decline in plant species diversity in European arable ecosystems, and pronounced shifts in species composition, including severe decreases in many species closely adapted to traditional agricultural practices. These changes in the arable vegetation have also resulted in pronounced losses of food and habitat resources for the dependent fauna. To counter these trends, and to conserve traditional arable plant communities, various strategies have been developed, ranging from an integration of conservation aspects into existing farming systems with a focus on crop production (“land sharing strategies”) to “land sparing” measures where conservation aspects take priority over crop production. This review gives an overview of those strategies, with a particular focus on arable plant conservation. Among the systems integrating species conservation into regular crop production, good results were achieved with organic farming and traditional “lowintensity farming systems”. Where production-focused management cannot deliver rare species persistence, targeted conservation measures are required. A wide range of such measures is available, e.g. in the form of conservation headlands, uncropped cultivated field margins, and wildflower strips, and in the form of arable reserves and fields primarily managed for conservation objectives. Finally, we discuss the possibility of re-introducing rare arable species at suitable sites, highlighting the importance of favourable management for successful establishment, based on existing experimental evidence. Lien pérenne : DOI : 10.1080/23818107.2016.1237886 Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=135361 Albrecht, Harald, Cambecèdes, Jocelyne, Lang, Marion, Wagner, Markus 2016 Management options for the conservation of rare arable plants in Europe. Botany letters, 163(4) .Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 25927A MYC Tiré à part Bureaux Mycologie Consultable Documents numériques
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