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Anna Lena Mueller Christian A. Berger Siegfried Schittenhelm Burkhard Stever-Schoo Jens Dauber 《Journal of Agronomy and Crop Science》2020,206(5):529-537
The perennial cup plant (Silphium perfoliatum L.) is considered as an alternative feedstock to maize for biogas plants. Due to its ecological advantages of an extensive management and function as food resource for pollinators, it can be grown in Ecological Focus Areas (EFAs) since 2018. However, studies at the Julius Kühn-Institute in Braunschweig (Germany) showed that the assumed advantage of the cup plant of a high drought tolerance could not be confirmed regarding aspects of crop production and yield. We complemented this experiment by assessing how different soil moisture conditions affect the production of floral resources and insect visitation. In 2014, we sampled three irrigated and three rainfed plots of the cup plant. We quantified the nectar volume and sugar mass per inflorescence, the number of inflorescences per plant and calculated the total nectar sugar production. We further counted insect visitation on the inflorescences. Due to reduced numbers of inflorescences per plant and an earlier harvest, the estimated nectar sugar production was 58 kg/ha regarding irrigated and 20 kg/ha regarding rainfed plots. Honeybee visitation per inflorescence was about twice as high in the irrigated plots. Furthermore, the early harvest is a disadvantage for wild pollinators with a late activity period. 相似文献
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Robert M. REES Juliette MAIRE Anna FLORENCE Nicholas COWAN Ute SKIBA Tony van der WEERDEN Xiaotang JU 《农业科学与工程前沿(英文版)》2020,7(1):75-80
Nitrous oxide (N2O) emissions make up a significant part of agricultural greenhouse gas emissions. There is an urgent need to identify new approaches to the mitigation of these emissions with emerging technology. In this short review four approaches to precision managements of agricultural systems are described based on examples of work being undertaken in the UK and New Zealand. They offer the opportunity for N2O mitigation without any reduction in productivity. These approaches depend upon new sensor technology, modeling and spatial information with which to make management decisions and interventions that can both improve agricultural productivity and environmental protection. 相似文献
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Anna Esposito Daniele DAlonzo Stefano DErrico Eliana De Gregorio Annalisa Guaragna 《Marine drugs》2020,18(11)
In the effort to improve the antimicrobial activity of iminosugars, we report the synthesis of lipophilic iminosugars 10a–b and 11a–b based on the one-pot conjugation of both enantiomeric forms of N-butyldeoxynojirimycin (NBDNJ) and N-nonyloxypentyldeoxynojirimycin (NPDNJ) with cholesterol and a succinic acid model linker. The conjugation reaction was tuned using the established PS-TPP/I2/ImH activating system, which provided the desired compounds in high yields (94–96%) by a one-pot procedure. The substantial increase in the lipophilicity of 10a–b and 11a–b is supposed to improve internalization within the bacterial cell, thereby potentially leading to enhanced antimicrobial properties. However, assays are currently hampered by solubility problems; therefore, alternative administration strategies will need to be devised. 相似文献
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Baranowska-Wójcik Ewa Szwajgier Dominik Winiarska-Mieczan Anna 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):30-32
Plant Foods for Human Nutrition - Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized, among others by abnormal levels of acetyl- and butyrylcholinesterase in... 相似文献
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Linking small pelagic fish and cetacean distribution to model suitable habitat for coastal dolphin species,Delphinus delphis and Tursiops truncatus,in the Greek Seas (Eastern Mediterranean) 下载免费PDF全文
Marianna Giannoulaki Evangelia Markoglou Vasilis D. Valavanis Paraskevi Alexiadou Anna Cucknell Alexandros Frantzis 《水产资源保护:海洋与淡水生态系统》2017,27(2):436-451
- A large‐scale assessment of the summertime suitable habitat for Delphinus delphis (short‐beaked common dolphin) and Tursiops truncatus (common bottlenose dolphin) in Greek Seas (Eastern Mediterranean) was conducted using data from dedicated and opportunistic cetacean surveys and published data records.
- Using a presence/absence approach, generalized additive models were applied to define a suite of environmental, bathymetric and biotic factors that best describe common and bottlenose dolphin spatial distribution, during early (May, June, July) and late (August, September) summer.
- A geographic information system (GIS) was used to integrate sightings data with environmental characteristics, distance from the coast and sardine probability of presence. These variables were considered as good proxies for defining species‐suitable habitat within the study area's coastal environment.
- The final selected models were used to produce annual probability maps of the presence of the species in the entire Greek Seas, as a measure of habitat suitability. Based on the mean probability and standard deviation maps for the study period GIS techniques were subsequently used to determine the persistent (areas with high mean and low variation) and occasional (high mean and high variation) habitat of each species.
- Results showed that there was a high probability of common dolphin presence in areas with a high probability of sardine presence. For bottlenose dolphin, higher probability of the presence of species occurred in areas closer to the shore, with a high probability of sardine presence and with high concentrations of chlorophyll‐a.
- In both seasons, the North Aegean Sea and the Inner Ionian Sea Archipelago were indicated as the most suitable areas for common dolphin distribution. Persistent habitat areas of the bottlenose dolphin included enclosed seas, continental shelf waters, and waters surrounding islands. The indicated suitable areas are discussed along with deficiencies of the models and future implications for conservation.
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Anna Kusumawati Benito Heru Purwanto Makruf Nurudin 《Soil Science and Plant Nutrition》2020,66(1):206-213
ABSTRACT Sugarcane is a strategic commodity in Indonesia. It is usually raised in a monoculture system. There is a lack of information about the effects of extended sugarcane monoculture on the soil carbon fraction. The aim of this study was to determine the relative changes in the soil organic C fractions in response to the duration of sugarcane monoculture on Entisols, Inceptisols, and Vertisols. The measured variables were the percentages of sand, silt, and clay, organic matter (OM), total nitrogen (TN), pH (H2O), cation exchange capacity (CEC), NH4 +, NO3 -, labile carbon fraction (soil carbon mineralization (C-Min), soil microbial carbon (C-Mic), and carbon particulate organic matter (C-POM)), and stable carbon fraction (humic and fulvic acids). Soil type with sugarcane monoculture period had significant influences on the percentages of clay, sand, silt, CEC, and pH (H2O). Soil type and sugarcane monoculture period had no apparent significant effect on C-Min or C-POM but did significantly influence C-Mic. The humic and fulvic acid levels in all three soil types were affected by the duration of sugarcane monoculture. To establish the impact of long-term sugarcane monoculture on the physicochemical properties of soils with various textures, it is more appropriate to measure the soil stable carbon fractions such as humic and fulvic acid rather than the soil labile carbon fractions such as C-Min, C-POM, or C-Mic. 相似文献