Water uptake by black spruce seedlings from rooting media (solution,sand, peat) treated with inorganic and oxalated aluminum     

Paul A. Arp  Irene Strucel 《Water, air, and soil pollution》1989,44(1-2):57-70

Experiments with solution cultures revealed that 1-yr-old black spruce (Picea mariana [Mill.]) seedlings growing in nutrient solutions experienced reductions in water uptake and moist plant weight when treated with water-soluble inorganic Al at the time of rapid shoot elongation. These reductions occurred with solution concentrations for Al at ≥ 16 mg L^?1. Wilting was noticed with Al ≥ 8 mg L^?1. In contrast, oxalated Al treatments had no visible effects on either water uptake or moist plant weight during shoot elongation. Later, near the time of budset, neither inorganic nor oxalated Al had an effect on moist plant weight or water uptake. This suggests that black spruce seedlings may or may not be susceptible to water-soluble inorganic Al depending on the degree of Al complexation afforded by the rooting medium, and by the plant roots at different times of the growing season. Water uptake was affected by the type of rooting medium in which the seedlings grew. For example, water uptake from peat was greater than water uptake from solution. Water uptake from sand was intermediate. Water uptake from solution-only cultures was probably affected by restricted O₂ supply.  相似文献   

Analysis of organophosphorus pesticides in dried ground ginseng root by capillary gas chromatography-mass spectrometry and -flame photometric detection     

Wong JW  Hennessy MK  Hayward DG  Krynitsky AJ  Cassias I  Schenck FJ 《Journal of agricultural and food chemistry》2007,55(4):1117-1128

A method was developed to determine organophosphorus pesticides (OPs) in dried ground ginseng root. Pesticides were extracted from the sample using acetonitrile/water saturated with salts, followed by solid-phase dispersive cleanup, and analyzed by capillary gas chromatography with electron ionization mass spectrometry in selective ion monitoring mode (GC-MS/SIM) and flame photometric detection (GC-FPD) in phosphorus mode. The detection limits for most of the pesticides were 0.025-0.05 microg/g using GC-FPD but were analyte-dependent for GC-MS/SIM, ranging from 0.005 to 0.50 microg/g. Quantitation was determined from 0.050 to 5.0 microg/g with r 2 > 0.99 for a majority of the pesticides using both detectors. Recovery studies were performed by fortifying the dried ground ginseng root samples to concentrations of 0.025, 0.1, and 1.0 microg/g, resulting in recoveries of >90% for most pesticides by GC-FPD. Lower (<70%) and higher (>120%) recoveries were most likely from complications of pesticide lability or volatility, matrix interference, or inefficient desorption from the solid-phase sorbents. There was difficulty in analyzing the ginseng samples for the OPs using GC-MS at the lower fortification levels for some of the OPs due to lack of confirmation. GC-FPD and GC-MS/SIM complement each other in detecting the OPs in dried ground ginseng root samples. This procedure was shown to be effective and was applied to the analysis of OPs in ginseng root samples. One particular sample, a ground and dried American ginseng (Panax quinquefolius) root sample, was found to contain diazinon quantified at approximately 25 microg/kg by external calibration using matrix-matched standards or standard addition using both detectors. The advantage of using both detectors is that confirmation can be achieved using GC-MS, whereas the use of a megabore column in GC-FPD can be used to quantitate some of the nonpolar OPs without the use of matrix-matched standards or standard addition.  相似文献   

Management of Select Bacterial and Parasitic Conditions of Raptors     

Michelle Willette  Julia Ponder  Luis Cruz-Martinez  Lori Arent  Irene Bueno Padilla  Olga Nicolas de Francisco  Patrick Redig 《Veterinary Clinics of North America: Exotic Animal Practice》2009,12(3):491-517

  相似文献   

New hosts for Lecanosticta acicola and Dothistroma septosporum in newly established arboreta in Spain     

Nebai Mesanza  Rosa Raposo  Margarita Elvira‐Recuenco  Irene Barnes  Ariska van der Nest  Mnica Hernndez  Maria Teresa Pascual  Iskander Barrena  Unai San Martín  Alejandro Cantero  Laura Hernandez‐Escribano  Eugenia Iturritxa 《Forest Pathology》2021,51(1):e12650

A historical outbreak of needle blight disease was recorded during 2018 to 2019 in plantations of Pinus radiata and Pinus nigra in the North of Spain. The main pathogens involved in this historical outbreak were identified as Lecanosticta acicola and Dothistroma septosporum. Recently, a variety of tree species in three arboreta planted between 2011 and 2013 in the Basque Country as part of the European project REINFFORCE were showing symptoms of needle blight and defoliation. The aim of this study was to determine which pine species were affected with these pathogens. Tree species sampled included several provenances of P. brutia, P. elliottii, P. nigra, P. pinaster, P. pinea, P. ponderosa, P. sylvestris and P. taeda. Using molecular identification methods, Lecanosticta acicola was confirmed infecting Pinus brutia (Provenance: Alexandropolis, Greece and var. eldarica, Crimea) and represents a new host species for this pathogen. Pinus elliottii (Provenance: Georgia, USA) and P. ponderosa (Provenance: Central California, USA) are new host reports of L. acicola for Spain. Dothistroma septosporum was found for the first time on P. brutia (Provenance: Marmaris, Turkey) and P. ponderosa (Provenance: Oregon, USA) in Spain and was also detected infecting P. nigra (Provenance: Sologne Vayrières, France).  相似文献   

Biological and chemical characterization of harbour sediments from the Stockholm area     

Britta Eklund  Maria Elfström  Irene Gallego  Bengt-Erik Bengtsson  Magnus Breitholtz 《Journal of Soils and Sediments》2010,10(1):127-141

Purpose  

The main objective of the current study was to assess the impact of pleasure boat activities on harbour sediment quality in the Stockholm area. Sediment contamination is a growing ecological issue, and there is consequently a need to use sediment bioassays in combination with chemical analysis to determine the impact on the ecosystem. To generate sediment toxicity data relevant for the Baltic Sea, a secondary objective was to further develop and evaluate two well-established bioassays for saltwater, with the macroalga Ceramium tenuicorne and the crustacean Nitocra spinipes, to be useful also for toxicity testing of whole sediment. A major concern has been to minimize any manipulation of the sediments. A third objective was to assess whether a simple leaching procedure could be used to simulate sediment toxicity by comparing results from whole sediment and leachate tests.  相似文献   

Multi-residue analysis of PAH, PCB, and OCP optimized for organic matter of forest soil     

Petra Lehnik-Habrink  Sebastian Hein  Tin Win  Wolfram Bremser  Irene Nehls 《Journal of Soils and Sediments》2010,10(8):1487-1498

Purpose

Analyzing organic pollutants in forest soil is challenging because they are strongly physical and chemical bound to soil organic matter (SOM). Within the framework of a forest soil inventory, an analytical protocol for the determination of polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB), and organochlorine pesticides (OCP) should be established and validated using one and the same extraction and cleanup procedure. The protocol should be applicable for reliable analysis of a high number of samples in a short timeframe.

Materials and methods

Two different soil samples representative for the humic layer from a typical mixed and coniferous forest soil had been used for the analysis. Three solvents of different polarity, namely cyclohexane (CH), ethylacetate (EA)/CH (1/1, v/v), and acetone (AC)/CH (2/1, v/v), and the six standard extraction techniques (pressurized liquid extraction (PLE), soxhlet extraction, fluidized bed extraction, sonication, shaking, and one-step extraction recommended for analyzing agricultural soil in Germany (VDLUFA 2008)) were compared concerning their extraction efficiency. For additional matrix separation, two different cleanup procedures (gel permeation chromatography (GPC) and solid-phase extraction (SPE) with different sorbents) were tested. Quantification was carried out using gas chromatography combined with mass spectrometry (GC–MS) and two different injection systems (split/splitless injection and programmable temperature vaporizer (PTV) injection). Labeled internal standards, added prior to extraction, were used for method evaluation.

Results and discussion

For the simultaneous extraction of PAH, PCB, and OCP from organic forest soil PLE with acetone/cyclohexane (2/1, v/v) provided the highest extraction efficiency. A two-step cleanup procedure consisting of GPC followed by SPE with silica gel was entirely sufficient for the separation of humic substances without discrimination of analytes. Recovery rates for the different extraction and cleanup steps ranged between 89% and 106%. For quantification, a GC–MS method was developed using two different injection systems and two capillary columns of different selectivity.

Conclusions

By comparing six standard extraction techniques for PAH, PCB, and OCP from forest soil, we obtained the highest extraction efficiency when using PLE with AC/CH (2/1). For sample injection, we achieved best results using an optimized PTV injection system as it highly reduced the breakdown of thermolabile pesticides. Using this combination of technical equipment, it is possible to determine a concentration of the analytes in the trace level range of 1–2 μg kg^?1 in humic soil.  相似文献   

Decomposition and nutrient release in leaves of Atlantic Rainforest tree species used in agroforestry systems     

Edivânia M. G. Duarte  Irene M. Cardoso  Thomas Stijnen  Maria Alice F. C. Mendonça  Marino S. Coelho  Reinaldo B. Cantarutti  Thomas W. Kuyper  Ecila M. A. Villani  Eduardo S. Mendonça 《Agroforestry Systems》2013,87(4):835-847

Aiming to support the use of native species from the Atlantic Rainforest in local agroforestry systems, we analysed chemical and biochemical components related to leaf decomposition of Inga subnuda, Senna macranthera, Erythrina verna, Luehea grandiflora, Zeyheria tuberculosa, Aegiphila sellowiana, and Persea americana. These tree species are native (except for P. americana) and commonly used in agroforestry systems in the Atlantic Rainforest. For the three first species (Fabaceae), we also analysed the remaining dry matter and released nutrients from leaves, using litter bags, and biological nitrogen fixation, using Bidens pilosa and Brachiaria plantaginea as references of non-N₂-fixing plants. Leaves from I. subnuda, L. grandiflora, and P. americana had a lower decomposition rate than the other species, exhibiting negative correlations with lignin/N and (lignin+polyphenol)/N ratios. The percentages of remaining dry matter after 1 year were 69 % (I. subnuda), 26 % (S. macranthera) and 16 % (E. verna). Higher nutrient release was found in decreasing order from residues of E. verna, S. macranthera, and I. subnuda. The percentages of nitrogen fixation were 22.6 % (E. verna), 20.6 % (I. subnuda) and 16.6 % (S. macranthera). Diversification of tree species in agroforestry systems allows for input of diversified organic material and can contribute to maintaining and improving soil functions resulting in improvements of soil quality.  相似文献   

Screening and selection of lentil (Lens Miller) germplasm resistant to seed bruchids (Bruchus spp.)     

Irene Laserna-Ruiz  Marcelino De-Los-Mozos-Pascual  Omar Santana-Méridas  Raúl Sánchez-Vioque  María Fernanda Rodríguez-Conde 《Euphytica》2012,188(2):153-162

Seed weevil (Bruchus spp.) is one of the most damaging pests to lentil crop, and the current chemical treatments to control this insect present numerous disadvantages. In this work, we have searched for resistant or almost resistant lentil cultivars to be used as potential sources of genes for resistance to bruchids as a more sustainable and environmentally friendly approach to diminish harvest loss. Thus, a lentil germplasm collection of 571 accessions from 27 different countries, and including wild species was screened for susceptibility to seed bruchids under natural field conditions in Central Spain. Infestation was evaluated in comparison with a check (lentil cultivar ??Lyda??) according to the number of eggs per pod and the infestation rate in seeds (IR). A large variation of IR (0?C70?%) was observed among accessions although, in general, wild species were consistently less affected by bruchids than the check. A total of 32 accessions, including Lens culinaris Medikus subsp. culinaris, Lens culinaris Medikus subsp. orientalis (Boiss.) Ponert, Lens nigricans (M. Bieb.) Godr., and Lens lamottei Cezfr., showed lower infestation rates than the check and were selected as potential sources of resistance to this pest. Potential mechanisms of resistance of selected accessions and their inclusion in a breeding program are outlined.  相似文献   

Transfer of insecticide residues to food stored on or near plywood impregnated with organochlorine insecticides     

F. Bernard Fishwick  Irene Rutter 《Pest management science》1982,13(3):263-268

Formulations of aldrin and dieldrin have been used for a number of years to treat exposed timber components used in the construction of freight containers. The extent to which these insecticides migrate to foodstuffs stored on or near treated plywood has been examined under laboratory conditions and is reported here. A limited survey of organochlorine insecticide residues in samples of foodstuffs, taken from commercial loads carried in freight containers, indicated that residue levels are unlikely to present a health hazard.  相似文献   

GIS-models work well, but are not enough: Habitat preferences of Lanius collurio at multiple levels and conservation implications     

Mattia Brambilla  Fabio Casale  Valentina Bergero  G. Matteo Crovetto  Riccardo Falco  Irene Negri  Paolo Siccardi  Giuseppe Bogliani 《Biological conservation》2009,142(10):2033-2042

Species conservation largely depends on knowledge of habitat needs of target species. GIS-models are increasingly used to assess habitat preferences and distribution of target species, but their accuracy is constrained by availability of digital data layers. We developed a two-steps approach aiming at showing pros and cons of landscape (GIS)- and site-level habitat models, identifying key habitat factors for conservation of a threatened bird species, the red-backed shrike Lanius collurio. A spatially explicit GIS-model was generated using landscape variables, and a second model at site level was developed using fine-scale variables measured on the ground. The GIS-based model was then extrapolated to the entire region to obtain a map of distribution of suitable habitats. Positive associations between shrike occurrence and both hedgerow length and partial shrub cover were detected at both scales. Shrikes were also positively associated with grassland cover at landscape level and with partial cover of untilled herbaceous vegetation at the finer scale, and negatively affected by lucerne cover. The GIS-model led to an affordable map of predicted habitat suitability which should help conservationists to focus on different local priorities, but was unable to identify effects of untilled and lucerne cover. Site-level model gave fine details for habitat management, but its application elsewhere requires ground-measurements of factors. Combining the multiscale models could indicate more urgent actions at large scales (e.g. maintaining suitable habitats, or improving connectivity among isolated patches) and draw a detailed figure of the most suitable habitat for the species. Shrike occurrence was associated with a higher number of shrub and tree species: the indicator value of the species should ensure general benefits for biodiversity from dedicated management.  相似文献