Magnitude of shear stress on the san andreas fault: implications of a stress measurement profile at shallow depth   总被引：1，自引：0，他引：1  

Zoback MD  Roller JC 《Science (New York, N.Y.)》1979,206(4417):445-447

A profile of measurements of shear stress perpendicular to the San Andreas fault near Palmdale, California, shows a marked increase in stress with distance from the fault. The pattern suggests that shear stress on the fault increases slowly with depth and reaches a value on the order of the average stress released during earthquakes. This result has important implications for both long- and shortterm prediction of large earthquakes.  相似文献   

Influence of high temperature and humidity on the reproductive performance of swine   总被引：3，自引：0，他引：3  

H S Teague  W L Roller  A P Grifo 《Journal of animal science》1968,27(2):408-411

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THE CRUCIAL POSTWAR NEED FOR AN INTERNATIONAL,AUXILIARY LANGUAGE FOR THE SCIENCES     

Roller D 《Science (New York, N.Y.)》1945,101(2621):299-300

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Trade-off between height growth and spring flushing in common beech (<Emphasis Type="Italic">Fagus sylvatica</Emphasis> L.)     

Dušan Gömöry  Ladislav Paule 《Annals of Forest Science》2011,68(5):975-984

• Introduction   

The annual development cycle of boreal and temperate trees results from an evolutionary trade-off between two opposing forces. These are namely, the adjustment of leaf phenology to the timing of frost occurrence at the beginning and/or the end of the growth season countered by an effective adjustment to the duration of the growth season to maximise photosynthesis and biomass production during the growing season.  相似文献   

Protein heterogeneity in European wheat landraces and obsolete cultivars   总被引：2，自引：0，他引：2  

Edita Gregová  Ji í Hermuth  Ján Kraic  Ladislav Dotla il 《Genetic Resources and Crop Evolution》1999,46(5):521-528

Identity and present degree of genetic homogeneity and heterogeneity, respectively of 52 European wheat accessions, maintained in the collection of wheat genetic resources, have been characterized using analyses of glutenins by sodiumdodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE). Six of the analyzed wheat accessions were observed to be homogeneous, while 46 (88.5%) of them were heterogeneous in protein profiles. Heterogeneous accessions possessed 2 to 13 different protein lanes. Together, 17 high molecular weight glutenin subunit (HMW-GS) alleles have been found. The most frequent HMW-GS alleles at the Glu-A1, Glu-B1, and Glu-D1 complex loci were 1, 7+9, and 2+12, respectively. However, also low frequented HMW-GS alleles or allelic combinations, such as 7+15, 13+16, 20, 6, 7, and 9 were observed. Furthermore, another new allele encoding HMW glutenin subunit with relative molecular weight 98.6 kDa has been found in one of the lines of the cultivar Eritrospermum 917. The Glu-score in the examined accessions varied in broad range, some of the lines reached the maximum value 10.  相似文献   

Serum and tissue ammonium nitrogen and tissue water values in ammonia-intoxicated sheep     

W C Kirkpatrick  M H Roller  R N Swanson 《American journal of veterinary research》1972,33(6):1187-1190

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Structure and diversity of small-mammal communities of lowland forests in the rural central European landscape     

Josef Suchomel  Luboš Purchart  Ladislav Čepelka 《European Journal of Forest Research》2012,131(6):1933-1941

Small-mammal communities were monitored over 4 years in South Moravian rural lowland forests in order to study relationships with various forest habitat types. Early successional sites (plantations) and forest edges maintained communities with higher abundance and diversity. Lowest total abundance was observed in unmanaged lowland forest and highest abundance in plantations with irregular undergrowth management. Low diversity was typical of non-fruiting monocultures. In plantations, both diversity and abundance were affected by herb layer removal, with sites subject to regular cutting, displaying lower levels. Significant differences in diversity and species richness were only detected between early and late successional sites, with the former showing higher values. Two basic small-mammal community groups were determined; (1) those inhabiting sites with a thick herb undergrowth and an open tree canopy (plantation) and (2) those inhabiting stands with sparse or no herb layer and a closed canopy (high forest). Forest stands support long-term populations of dominant small forest-dwelling mammal species and, as such, serve as reservoirs, even in rural landscapes dominated by intensive arable farming. Managed early succession lowland forests represent important refuges for a number of small open-habitat mammals negatively affected by intensive farming.  相似文献   

Improved method for comparing abundance data for soil zoological field studies     

Josef Rusek  Vladimír Balík  Ladislav Hnl  Jan Frouz 《European Journal of Soil Biology》1999,35(3):145

Soil bulk density varies among sites as well as microhabitats, and in different years at the same site. Bulk density is a highly variable parameter that introduces undefined but significant errors to abundance field data of soil microfauna when given in individuals per g soil dry mass (sdm). Such data are not comparable among sites, microhabitats and years and they are unsuitable for comparative ecological field studies. Soil corer sampling technique, defined as soil surface square units (e.g. 1 cm²), is recommended to overcome the methodological imprecision of estimating abundance of soil microfauna from field studies in ind·g sdm. This removes consideration of variable soil bulk density and enables us to establish abundance values directly in ind·cm⁻² without any recalculations. Resultant data are comparable both spatially and temporally. Abundance data as individuals per m² is a commonly used unit for soil meso-, macro- and megafauna.

Résumé

La densité apparente du sol est extrêmement variable aussi bien selon les sites que selon les microhabitats, ainsi que selon les différentes années sur un même site. La variabilité de ce paramètre induit des erreurs mal définies, mais significatives, dans l'estimation des abondances de la microfaune du sol lorsque celles-ci sont produites en termes de nombre d'individus par gramme de sol sec. De telles données ne sont pas comparables entre sites, microhabitats, ou années, et ne sont donc pas utilisables pour des études d'écologie comparative. La méthode d'échantillonnage par carottage du sol sur une surface connue (par exemple 1 cm²) est recommandée afin de maîtriser l'imprécision liée aux estimations par poids de sol sec. Cela permet de s'affranchir du paramètre de densité apparente du sol et permet de donner directement des valeurs d'abondance en nombre d'individus par cm² sans aucun calcul. Les données ainsi exprimées sont comparables, à la fois spatialement et temporellement. Le nombre d'individus par m² est une unité communément utilisée pour la méso-, macro- et mégafaune.  相似文献   

Regional Contamination of Moravia (South-Eastern Czech Republic): Temporal Shift of Pb and Zn Loading in Fluvial Sediments     

Matys Grygar  Tomáš  Sedláček  Jan  Bábek  Ondřej  Nováková  Tereza  Strnad  Ladislav  Mihaljevič  Martin 《Water, air, and soil pollution》2012,223(2):739-753

Regional contamination by Pb and Zn in southern Moravia (south-east part of the Czech Republic) in the twentieth century was analysed in Brno Dam lake sediments and in floodplain sediments of the Morava River near Strážnice. The age model for the Brno Dam lake sediments has been obtained by ¹³⁷Cs (maxima corresponding to the nuclear tests in atmosphere and the 1986 Chernobyl accident) and the construction of the dam (1940); the time constraints for the Morava River sediments was the erection of flood defences (1930s) and ²¹⁰Pb dating. In the case of floodplain sediments, profiles exhibiting post-depositional mobilisation of heavy metals by pedogenic processes (gleying) must be excluded to reconstruct the history of contamination. There was a relatively fast joint onset of Pb and Zn load since the early stages of industrialisation in the first half of the twentieth century, but then the concentrations of these two metals developed in a different manner. Pb load only slightly increased till its peak in 1960s and 1970s. The increase of Zn load was rather stepwise: Soon before 1930s (Morava River floodplain) and in 1940s and 1950s (in Brno Lake), the relative contamination by Zn was much lower than during its peak in the 1970s to the present days. The offset of Pb and Zn contamination curves could have been caused by three different artificial sources of these heavy metals. The temporal shift of Pb and Zn loads can be used for dating sediments.  相似文献   

Map-based investigation of soil physical conditions and crop yield using diverse sensor techniques   总被引：1，自引：0，他引：1  

Y. Sun  H. Druecker  E. Hartung  H. Hueging  Q. Cheng  Q. Zeng  W. Sheng  J. Lin  O. Roller  S. Paetzold  P. Schulze Lammers   《Soil & Tillage Research》2011,112(2):149-158

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