全文获取类型
收费全文 | 59篇 |
免费 | 2篇 |
专业分类
林业 | 11篇 |
农学 | 1篇 |
30篇 | |
综合类 | 2篇 |
农作物 | 1篇 |
水产渔业 | 3篇 |
畜牧兽医 | 9篇 |
园艺 | 3篇 |
植物保护 | 1篇 |
出版年
2021年 | 4篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 2篇 |
2013年 | 6篇 |
2012年 | 3篇 |
2011年 | 4篇 |
2010年 | 2篇 |
2009年 | 2篇 |
2008年 | 3篇 |
2007年 | 6篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
1999年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1989年 | 1篇 |
1978年 | 1篇 |
1971年 | 2篇 |
排序方式: 共有61条查询结果,搜索用时 31 毫秒
51.
Lukáš Hlisnikovský Michal Hejcman Eva Kunzová Ladislav Menšík 《Archives of Agronomy and Soil Science》2019,65(2):152-163
Triticum monococcum L., Triticum dicoccum Schrank and Triticum spelt L. nowadays offer an alternative to Triticum aestivum L. We analyzed grain and straw yield, yielding parameters, chemical composition and bakery quality of these species and compared them with modern T. aestivum at three sites with different soil-climate conditions. The average grain yield varied from 0.41 t ha?1 (T. monococcum) to 5.17 t ha?1 (T. aestivum), straw yield varied from 1.50 t ha?1 (T. dicoccum) to 5.83 t ha?1 (T. aestivum). The yielding parameters and chemical composition of the grain were significantly influenced by soil-climate conditions and wheat species. The highest average crude protein content was recorded in T. spelta (20.55%), while the lowest in T. aestivum (11.20%). The Zeleny’s sedimentation test ranged from 9.0 ml (T. monococcum) to 34.5 ml (T. aestivum) and the value of the Gluten index varied from 7.45 (T. dicoccum) to 89.75 (T. aestivum). According to the results, ancient wheat species provides lower grain and straw yields, higher protein content and mineral concentrations. Concentration of proteins and grain’s baking quality strongly depends on wheat species and soil-climate conditions. 相似文献
52.
Redistribution of organic pollutants in river sediments and alluvial soils related to major floods 总被引:2,自引:5,他引:2
Klara Hilscherova Ladislav Dusek Vratislav Kubik Pavel Cupr Jakub Hofman Jana Klanova Ivan Holoubek 《Journal of Soils and Sediments》2007,7(3):167-177
Background, Aims, and Scope More frequent occurrence of stronger floods in Europe as well as in other parts of the world in recent years raises major
concern about the material damages, but also an important issue of contamination of the affected areas through flooding. The
effects of major floods on levels and distribution of contamination with hydrophobic organic pollutants were examined from
the continuous set of data for floodplain soils and sediments from a model industrial area in the Czech Republic where a 100-year
flood occurred in 1997. The goal of this study was to evaluate the risk related to contamination associated with such extensive
natural events and characterize the spatial and temporal distribution and dynamics of pollutants related to a major flooding
shortly after the floods and also in the time period several years after floods.
Methods Sediments and alluvial soils from fourteen sites each were repeatedly sampled during the period from 1996 until 2005. The
sampling sites represented five regions. Collected top-layer sediment and soil samples were characterized and analyzed for
hydrophobic organic pollutants PCBs, OCPs and HCB using GC-ECD and PAHs using a GC-MS instrument. Spatial and temporal differences
as well as the relative distribution of the pollutants were examined in detail by statistical analysis including multivariate
methods with special emphases placed on the changes related to floods.
Results The organic pollutants levels in both alluvial soils and sediments exceeded the safe environmental limits at numerous sites.
Pollutants concentrations and relative distribution as well as organic carbon content in both sediment and floodplain soils
were significantly affected by the flooding, which resulted in a decrease of all studied contaminants in sediments and significant
rise of the PAH pollution in the flooded soils. There was a unique and highly conserved PAH pattern in soils regardless of
the floods and greater changes in PAH pattern in sediments related to floods. The relative distribution of individual PAHs
reflected a combustion generated PAH profile. PAH levels in the river sediments rose again at the sites with continuous sources
several years after floods.
Discussion The results showed different dynamics of PAHs and PCBs during the floods when PAHs were redistributed from the sediments to
alluvial soils while PCBs have been washed out of the study regions. The data reveal longer contamination memory and consistent
contamination pattern in soils, whereas sediments showed more dynamic changes responding strongly to the actual situation.
The stable PAH pattern within the regions also indicates that a relative amount of all compounds is comparable across the
samples and, thus, that the sources at different sites have similar character.
Conclusions Sediments have the potential to function as a secondary source of contamination for the aquatic ecosystem, but also for the
floodplain soils and other flooded areas. The floods served as a vector of PAHs contamination from sediments to soils. The
reloading of river sediments in time, namely with PAHs, due to present sources increases their risk as a potential source
in the next bigger flood event both to the downstream river basin and affected alluvial soils.
Recommendations and Perspectives The results stress the importance of including the floodplain soil contamination in the risk assessment focused on flood effects.
Floodplain soils have stable long-term environmental memory related to contamination levels, pattern and distribution, whereby
they can provide relevant information on the overall contamination of the area. The sediments will continue to serve as a
potential source of contaminants and alluvial soils as the catchment media reflecting the major flood events, especially until
effective measures are taken to limit contamination sources.
ESS-Submission Editor: Dr. Henner Hollert (Hollert@uni-heidelberg.de)
This article is openly accessible! 相似文献
53.
Spatial patterns and temporal changes of heavy metal distributions in river sediments in a region with multiple pollution sources 总被引:1,自引:1,他引:0
Zdenka Bednarova Jan Kuta Lukas Kohut Jiri Machat Jana Klanova Ivan Holoubek Jiri Jarkovsky Ladislav Dusek Klara Hilscherova 《Journal of Soils and Sediments》2013,13(7):1257-1269
Purpose
The main purpose of this study was to evaluate temporal and regional variability of contamination by heavy metals (HMs) in river sediments using their enrichment factors (EFs) and benchmarking according to sediment quality guidelines (SQGs). The Zlin region in the Czech Republic (Morava and Drevnice River basins) represents a model area where several regionally specific ecological risk assessment studies have recently been conducted with a focus on organic pollution, eco-toxicity, geological, and geochemical characteristics.Materials and methods
Four consecutive sediment sampling campaigns were undertaken in spring and autumn 2005–2006. Aqua-regia leachable content of Cd, Co, Cr, Cu, Ni, Pb, Sb, V, and Zn in surface sediments from 14 sites was analyzed using ICP-MS, and Hg content was analyzed using AMA-254 analyzer. EFs were calculated to identify the human impact on pollution in the area. Comparisons to SGQs were conducted to identify the areas and HMs of greatest risk.Results and discussion
Calculation of EFs contributed to the effective clustering of HMs. Median EFs of Co, Ni, and V ranged from 0.9 to 1.4 at all sites indicating concentrations very close to natural geological background levels. There was greater enrichment at locally polluted sites, the highest in the cases of Cd, Sb, Hg, and Cr. Widespread influence of diffuse HM sources (traffic, agriculture, and urban wastes) was apparent from elevated concentrations of Pb, Cu, and Zn at all sites. EF values also helped to identify the greatest temporal changes and shifts in HMs contamination between adjacent sites caused by 50-year recurrence interval floods in early spring 2006. The impact was most apparent in downstream sites; namely directly below the confluence of the two major rivers.Conclusions
The overall contamination of HMs in the region was classified as low-to-moderate with significantly contaminated sub-areas. The study showed relatively stable spatial distributions of HMs, indicating potential sources of pollution. Cu was identified as the HM of greatest risk. The study emphasizes the necessity of considering both environmental circumstances and background HM occurrence to prevent misinterpretation of the pollution situation. The use of EFs which include grain size proxy normalization and HM background levels, along with the comparison of the detected concentrations to SQGs, proved an efficient way to identify hazardous contamination from anthropogenic sources. 相似文献54.
Tereza Novakova Tomas Matys Grygar Ondrej Babek Martin Famera Martin Mihaljevic Ladislav Strnad 《Journal of Soils and Sediments》2013,13(2):460-473
Purpose
Regional contamination of southern Moravia (SE part of the Czech Republic) by trace metals and magnetic particles during the twentieth century was quantified in fluvial sediments of the Morava River. The influence of local pollution sources on regional contamination of the river sediments and the effect of sampling site heterogeneity were studied in sediment profiles with different lithologies.Materials and methods
Hundreds of sediment samples were obtained from regulated channel banks and naturally inundated floodplains and proxy elemental analyses were carried out by energy dispersive X-ray fluorescence spectroscopy (ED XRF) and further calibrated by inductively coupled plasma mass spectrometry (ICP MS). Magnetic susceptibility was determined as a proxy for industrial contamination. The age model for the floodplain sediments was established from 137Cs and 210Pb dating. Trace metal contamination was assessed by establishing the lithological background values from floodplain profiles and calculating enrichment factors (EF) of trace metals (i.e. Pb, Zn, Cu) and magnetic susceptibility for the entire study area.Results and discussion
Channel sediments are unsuitable for the reconstruction of historical regional contamination due to their lithological heterogeneity and the “chaotic” influence of local sources of contamination, as well as the possibility of geochemical mobility of pollutants. On the other hand, sediments from regulated river banks qualitatively reflected the actual, local contamination of the river system.Conclusions
This approach allowed us to distinguish the influence of local sources of contamination by comparison with more spatially averaged contamination signals from distal floodplain profiles. The studied area is weakly contaminated (EF ~1–2), while individual sediment strata from regulated channel banks reflect local sources of contamination and contain up to several times higher concentrations of trace metals. 相似文献55.
Eva Krascsenitsová Milan Kozánek Ján Ferenčík Ladislav Roller Christian Stauffer Coralie Bertheau 《Journal of pest science》2013,86(4):669-676
The Carpathians are a range of mountains forming an arc roughly 1,500 km long across Central and Eastern Europe. They are an important area for biodiversity and belong to one of the major refuges of the last ice ages for many organisms. The forests of the Carpathians are dominated by spruce, which have suffered continuous outbreaks of the eight spined spruce bark beetle, Ips typographus, in recent decades. The phylogeography of this spruce pest is well documented, however, little is known on small scale, i.e., the Carpathians. Here we applied a mitochondrial marker and studied the genetic variation and structure of Carpathian populations and compared data with published one from other European populations. Twelve haplotypes were characterized and 42 % of those were not detected in other European populations. Despite a slight genetic structure, differences were observed in the haplotype distribution and diversity between the Western/Southern Carpathians and the Eastern Carpathians reflecting at least two potential refugial areas for I. typographus within the Carpathian mountain system. Further data show that the Eastern Beskidian Mountains of the Carpathians could act as barrier for several European haplotypes. This small-scale analysis reveals that the Carpathians have been an important glacial and post-glacial refuge for I. typographus. This information is important for a preventive and reactive forest management. 相似文献
56.
57.
Ladislav Cséfalvay Gabriele Di Gaspero Karel Matouš Diana Bellin Benedetto Ruperti Julie Olejníčková 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(2):291-302
Plasmopara viticola is an economically important pathogen of grapevine. Early detection of P. viticola infection can lead to improved fungicide treatment. Our study aimed to determine whether chlorophyll fluorescence (Chl-F)
imaging can be used to reveal early stages of P. viticola infection under conditions similar to those occurring in commercial vineyards. Maximum (FV/FM) and effective quantum yield of photosystem II (ΦPSII) were identified as the most sensitive reporters of the infection. Heterogeneous distribution of FV/FM and ΦPSII in artificially inoculated leaves was associated with the presence of the developing mycelium 3 days before the occurrence
of visible symptoms and 5 days before the release of spores. Significant changes of FV/FM and ΦPSII were spatially coincident with localised spots of inoculation across the leaf lamina. Reduction of FV/FM was restricted to the leaf area that later yielded sporulation, while the area with significantly lower ΦPSII was larger and probably reflected the leaf parts in which photosynthesis was impaired. Our results indicate that Chl-F can
be used for the early detection of P. viticola infection. Because P. viticola does not expand systemically in the host tissues and the effects of infection are localised, Chl-F imaging at high resolution
is necessary to reveal the disease in the field. 相似文献
58.
Pernilla Carlsson Jaromír Literák Ladislav Dušek Jakub Hofman Thomas D. Bucheli Jana Klánová 《Journal of Soils and Sediments》2016,16(6):1718-1726
Purpose
The scope of this article was to investigate the spatial and temporal variability of enantiomeric fractions (EFs) of persistent organic pollutants (POPs) in soil compared to the uncertainty of the analytical data.Materials and methods
Soil samples were taken with high spatial resolution at two sites in Czech Republic in 2008 to investigate variability on a small spatial scale. In addition, composite soil samples were taken from ten sites in 2005 and 2008 to investigate temporal variations. All samples were analysed for a suite of soil properties as well as concentrations and EFs of polychlorinated biphenyl (PCB) -95, PCB-132 and PCB-149; α-hexachlorocyclohexane (HCH); o,p′-dichlorodiphenyltrichloroethane (DDT); and o,p′-dichlorodiphenyldichloroethane (DDD).Results and discussion
Median EFs of PCB-95 and PCB-149, α-HCH, o,p′-DDT and o,p′-DDD did not change significantly on the sites sampled in 2005 and again in 2008, while PCB-132 changed from EF?=?0.38 to EF?=?0.53. The sampling methodology is therefore very important, and composite samples will not be the best option if enantioselective degradation processes are investigated. Non-racemic EFs of POPs in the subsampled sites in 2008 were correlated to soil parameters, such as total organic carbon (TOC), total nitrogen and humic acids. These parameters are site specific and might vary on a small scale. This can explain why certain soil parameters are reported as significantly correlated with non-racemic EFs of chiral POPs in some studies, but not always in other similar studies.Conclusions
While composite samples may still represent the overall prevailing EF range, they are not ideally suited to study enantiomeric degradation processes, which are taking place at a relative small scale, depending on the heterogeneity of soil parameters such as TOC, total organic nitrogen (TON) and humic acids.59.
60.
Edita Gregová Jiří Hermuth Ján Kraic Ladislav Dotlačil 《Genetic Resources and Crop Evolution》2006,53(5):867-871
The endosperm storage protein of 46 European wheat (Triticum aestivum L.) landraces and obsolete cultivars have been fractionated by SDS-PAGE to determine the composition of high molecular weight
glutenin subunits (HMW-GS) composition. It has been discovered that about 46% of the wheats were heterogeneous, comprising
2–11 different glutenin profiles. Eighteen of them were observed to be homogeneous. A total of 13 HMW-GS alleles, including
3 at the Glu-A1, 8 at the Glu-B1, and 3 at the Glu-D1 loci were revealed. HMW-GS null controlled by locus Glu-A1, subunits 7 + 8 by Glu-B1, and 2 + 12 by Glu-D1 predominated. However low frequented alleles such as 17 + 18, 20, 6, and 7 were observed. Furthermore, other new alleles
encoding HMW-GS at the locus Glu-B1 have been found in one of France cultivar (Saumur d’Automne). The glutenin-based quality score ranged from 4 to 10. 相似文献