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51.
Pesticide exposure assessment for surface waters in the EU. Part 1: Some comments on the current procedure 下载免费PDF全文
Martin Bach Mirjam Diesner Dietlinde Großmann Djamal Guerniche Udo Hommen Michael Klein Roland Kubiak Alexandra Müller Jan Priegnitz Kai Thomas Matthias Trapp 《Pest management science》2016,72(7):1279-1284
In 2001, the European Commission introduced a risk assessment project known as FOCUS (FOrum for the Coordination of pesticide fate models and their USe) for the surface water risk assessment of active substances in the European Union. Even for the national authorisation of plant protection products (PPPs), the vast majority of EU member states still refer to the four runoff and six drainage scenarios selected by the FOCUS Surface Water Workgroup. However, our study, as well as the European Food Safety Authority (EFSA), has stated the need for various improvements. Current developments in pesticide exposure assessment mainly relate to two processes. Firstly, predicted environmental concentrations (PECs) of pesticides are calculated by introducing model input variables such as weather conditions, soil properties and substance fate parameters that have a probabilistic nature. Secondly, spatially distributed PECs for soil–climate scenarios are derived on the basis of an analysis of geodata. Such approaches facilitate the calculation of a spatiotemporal cumulative distribution function (CDF) of PECs for a given area of interest and are subsequently used to determine an exposure concentration endpoint as a given percentile of the CDF. For national PPP authorisation, we propose that, in the future, exposure endpoints should be determined from the overall known statistical PEC population for an area of interest, and derived for soil and climate conditions specific to the particular member state. © 2016 Society of Chemical Industry 相似文献
52.
Dissolved and colloidal phosphorus fluxes in forest ecosystems—an almost blind spot in ecosystem research 下载免费PDF全文
Roland Bol Dorit Julich Dominik Brödlin Jan Siemens Klaus Kaiser Michaela Anna Dippold Sandra Spielvogel Thomas Zilla Daniela Mewes Friedhelm von Blanckenburg Heike Puhlmann Stefan Holzmann Markus Weiler Wulf Amelung Friederike Lang Yakov Kuzyakov Karl‐Heinz Feger Nina Gottselig Erwin Klumpp Anna Missong Carola Winkelmann David Uhlig Jakob Sohrt Klaus von Wilpert Bei Wu Frank Hagedorn 《植物养料与土壤学杂志》2016,179(4):425-438
Understanding and quantification of phosphorus (P) fluxes are key requirements for predictions of future forest ecosystems changes as well as for transferring lessons learned from natural ecosystems to croplands and plantations. This review summarizes and evaluates the recent knowledge on mechanisms, magnitude, and relevance by which dissolved and colloidal inorganic and organic P forms can be translocated within or exported from forest ecosystems. Attention is paid to hydrological pathways of P losses at the soil profile and landscape scales, and the subsequent influence of P on aquatic ecosystems. New (unpublished) data from the German Priority Program 1685 “Ecosystem Nutrition: Forest Strategies for limited Phosphorus Resources” were added to provide up‐to‐date flux‐based information. Nitrogen (N) additions increase the release of water‐transportable P forms. Most P found in percolates and pore waters belongs to the so‐called dissolved organic P (DOP) fractions, rich in orthophosphate‐monoesters and also containing some orthophosphate‐diesters. Total solution P concentrations range from ca. 1 to 400 µg P L?1, with large variations among forest stands. Recent sophisticated analyses revealed that large portions of the DOP in forest stream water can comprise natural nanoparticles and fine colloids which under extreme conditions may account for 40–100% of the P losses. Their translocation within preferential flow passes may be rapid, mediated by storm events. The potential total P loss through leaching into subsoils and with streams was found to be less than 50 mg P m?2 a?1, suggesting effects on ecosystems at centennial to millennium scale. All current data are based on selected snapshots only. Quantitative measurements of P fluxes in temperate forest systems are nearly absent in the literature, probably due to main research focus on the C and N cycles. Therefore, we lack complete ecosystem‐based assessments of dissolved and colloidal P fluxes within and from temperate forest systems. 相似文献
53.
Parjeet Singh Aulakh Major S. Dhaliwal Salesh Kumar Jindal Roland Schafleitner Kuldeep Singh 《Plant Breeding》2016,135(4):531-535
Most of the hybrid seed in chilli are produced manually, but the use of male sterility (MS) can reduce the cost of hybrid seed production. MS‐12, a nuclear male‐sterile (NMS) line developed at Punjab Agricultural University, Ludhiana (India), has been utilized to develop commercial F1 hybrids. A recessive gene, designated as ms10, governs MS in MS‐12. Due to recessive gene control, development of new NMS lines incorporating ms10 gene is tedious and time‐consuming. We identified SSR markers AVRDC‐PP12 and AVRDC_MD997* linked to the ms10 gene. A total of 558 primer pairs were screened following bulked segregant analysis (BSA). Linkage analysis in 210 F2 plants indicated that the two SSR markers were linked to the ms10 gene and the marker AVRDC‐PP12 was closest to the gene at 7.2 cM distance. The marker was mapped to chromosome 1 at genome position 175 694 513 to 175 694 644. Until more closely linked markers are developed, the marker AVRDC‐PP12 would facilitate transfer of ms10 gene through marker‐assisted selection (MAS). Fine mapping would lead to cloning of the ms10 gene. 相似文献
54.
Journal of Plant Diseases and Protection - Factors influencing the sprouting ability of rhizome pieces of Calystegia sepium and root pieces of Convolvulus arvensis were analyzed in four... 相似文献
55.
Journal of Plant Diseases and Protection - Roots, collars and rhizosphere soils from diseased boxwood saplings (Buxus sempervirens) from German and Romanian nurseries were shown to be colonized by... 相似文献
56.
Peter Hanson Roland Schafleitner Shu-Mei Huang Chee-Wee Tan Dolores Ledesma Ray-Yu Yang 《Euphytica》2014,200(3):441-454
Consumption of flavonoids found in fruits and vegetables is linked to beneficial health outcomes. Tomato is among the most widely consumed and economically important vegetables worldwide and improvement of the nutrient content could lead to significant health benefits. Rutin, (quercetin-3-rutinoside), the main flavonol in tomato fruit, is confined to the peel. Rutin synthesis is limited by low expression of chalcone isomerase, the enzyme catalyzing the conversion of naringenin chalcone to naringenin quercetin. The wild tomato species Solanum habrochaites is a major source of new alleles to improve cultivated tomato (Solanum lycopersicum). AVRDC—The World Vegetable Center identified introgression line (IL) LA3984 containing a segment of S. habrochaites on chromosome 5 expressing high levels of rutin in full red ripe fruit. An AVRDC high rutin tomato line evaluated for 2 years and two seasons in Taiwan produced mean rutin content about four- to five-fold greater than the mean of all entries and about 11–12 times higher than the commercial fresh market and processing tomato cultivars. The quantitative trait locus (QTL) conditioning high rutin content was mapped to a 0.42 Mb segment on chromosome 5 flanked by markers c2_At3g55120/TaqI and ch05-4.883/ApaLI. Marker c2_Atg55120 overlaps with the chalcone-flavonone isomerase gene Solyc05g10320, and a second chalcone-flavonone isomerase gene is located 3,000 bp upstream from c2_At3g551220. Results of this project will facilitate breeding of high flavonoid tomato lines. 相似文献
57.
Petra Kahle Christel Baum Barbara Boelcke Josefine Kohl Roland Ulrich 《植物养料与土壤学杂志》2010,173(5):737-746
Short‐rotation forestry (SRF) on arable soils has high potentials for biomass production and leads to long‐term no‐tillage management. In the present study, the vertical distributions of soil chemical and microbial properties after 15 y of SRF with willows and poplar (Salix and Populus spp.) in 3‐ and 6‐year rotations on an arable soil were measured and compared to a pertinent tilled arable site. Two transects at different positions in the relief (upper and lower slope; transect 1 and 2) were investigated. Short‐rotation forestry caused significant changes in the vertical distribution of all investigated soil properties (organic and microbial C, total and microbial N, soil enzyme activities), however, the dimension and location (horizons) of significant effects varied. The rotation periods affected the vertical distribution of the soil properties within the SRF significantly. In transect 1, SRF had higher organic‐C concentrations in the subsoil (Bv horizon), whereas in transect 2, the organic‐C concentrations were increased predominantly in the topsoil (Ah horizon). Sufficient plant supply of P and K in combination with decreased concentrations of these elements in the subsoil under SRF pointed to an effective nutrient mobilization and transfer from the deeper soil horizons even in the long term. In transect 1, the microbial‐C concentrations were higher in the B and C horizons and in transect 2 in the A horizons under SRF than under arable use. The activities of β‐glucosidases and acid phosphatases in the soil were predominantly lower under SRF than under arable use in the topsoil and subsoil. We conclude, that long‐term SRF on arable sites can contribute to increased C sequestration and changes in the vertical distribution of soil microbial biomass and soil enzyme activities in the topsoil and also in the subsoil. 相似文献
58.
Influence of fertilization on acrylamide formation during frying of potatoes harvested in 2003 总被引:3,自引:0,他引:3
De Wilde T De Meulenaer B Mestdagh F Govaert Y Vandeburie S Ooghe W Fraselle S Demeulemeester K Van Peteghem C Calus A Degroodt JM Verhé R 《Journal of agricultural and food chemistry》2006,54(2):404-408
The quality of the potato has been found to vary, when grown under different agricultural and environmental conditions, such as the level of fertilization. Consequently these factors may influence the acrylamide formation during the preparation of French fries. These assumptions were studied on three varieties: Bintje, Ramos, and Saturna from the harvest of 2003. Decreasing N fertilization caused increases in the reducing sugar concentration from 60% up to 100% on DM for all varieties studied. Due to a high correlation between the reducing sugar content and the generation of acrylamide during frying, this resulted in a parallel increase in the acrylamide concentration of the French fries. Thus by lowering the amount of N fertilizer, an increase of 30-65% of the acrylamide generation during frying could be observed. It seems of extreme importance to find an appropriate balance between the level of N fertilizer in order to diminish acrylamide formation but on the other hand to obtain an acceptable tuber and to consider the environmental impact. All results reported should be seen in the perspective of the warm growing season of 2003. 相似文献
59.
Tessa Mazor C. Roland Pitcher Wayne Rochester Michel J. Kaiser Jan G. Hiddink Simon Jennings Ricardo Amoroso Robert A. McConnaughey Adriaan D. Rijnsdorp Ana M. Parma Petri Suuronen Jeremy Collie Marija Sciberras Lara Atkinson Deon Durholtz Jim R Ellis Stefan G. Bolam Michaela Schratzberger Elena Couce Jacqueline Eggleton Clement Garcia Paulus Kainge Sarah Paulus Johannes N. Kathena Mayya Gogina P. Daniël van Denderen Aimee A. Keller Beth H. Horness Ray Hilborn 《Fish and Fisheries》2021,22(1):72-86
Bottom trawl fishing is a controversial activity. It yields about a quarter of the world's wild seafood, but also has impacts on the marine environment. Recent advances have quantified and improved understanding of large‐scale impacts of trawling on the seabed. However, such information needs to be coupled with distributions of benthic invertebrates (benthos) to assess whether these populations are being sustained under current trawling regimes. This study collated data from 13 diverse regions of the globe spanning four continents. Within each region, we combined trawl intensity distributions and predicted abundance distributions of benthos groups with impact and recovery parameters for taxonomic classes in a risk assessment model to estimate benthos status. The exposure of 220 predicted benthos‐group distributions to trawling intensity (as swept area ratio) ranged between 0% and 210% (mean = 37%) of abundance. However, benthos status, an indicator of the depleted abundance under chronic trawling pressure as a proportion of untrawled state, ranged between 0.86 and 1 (mean = 0.99), with 78% of benthos groups > 0.95. Mean benthos status was lowest in regions of Europe and Africa, and for taxonomic classes Bivalvia and Gastropoda. Our results demonstrate that while spatial overlap studies can help infer general patterns of potential risk, actual risks cannot be evaluated without using an assessment model that incorporates trawl impact and recovery metrics. These quantitative outputs are essential for sustainability assessments, and together with reference points and thresholds, can help managers ensure use of the marine environment is sustainable under the ecosystem approach to management. 相似文献
60.
Effects of atmospheric and climate change at the timberline of the Central European Alps 总被引:1,自引:0,他引:1
Gerhard Wieser Rainer Matyssek Roland Luzian Peter Zwerger Peter Pindur Walter Oberhuber Andreas Gruber 《Annals of Forest Science》2009,66(4):402-402