Search results for "temporal scale"
showing 6 items of 36 documents
Millennial-scale terrestrial ecosystem responses to Upper Pleistocene climatic changes: 4D-reconstruction of the Schwalbenberg Loess-Palaeosol-Sequen…
2021
Abstract Loess-Palaeosol-Sequences (LPS) in the Central European region provide outstanding terrestrial polygenetic and multiphase archives responding to past climate and environments over various spatial and temporal scales. As yet, however, the geomorphological and pedogenic processes involved in LPS formation, and their interplay with changes in ecological conditions, impede robust correlation with other palaeoenvironmental archives. The Schwalbenberg LPS, which drape a hillslope in the Middle Rhine Valley in western Central Europe, provide unique high-resolution records highly suitable for investigating the processes involved in their formation and the relationship to climatic influence…
Mechanisms involved in spatial and temporal mobility of disease patches caused by Rhizoctonia solani in sugar beet field : Induction of antagonists w…
2008
National audience; Rhizoctonia solani AG 2-2 causes damping-off and root rot on sugar beet in patches that are highly mobile both on spatial and temporal scales. They never occur in the same place where they were in the previous season. The aim of the present study was to uncover the mechanisms underlying the dynamics of disease patches. It was observed that soil inoculum potential was higher within diseased patch than in healthy area. However, the dormant pathogen in healthy area was stimulated by addition of buckwheat meal more than that in diseased patch. In addition soil from diseased area was more suppressive towards the disease. We did not observe significant differences in bacterial …
Reduction in site fidelity with smaller spatial scale may suggest scale-dependent information use
2014
Animals change the strategy that they use to select breeding sites at the spatial scales of habitat, patch, and microhabitat. In this regard, breeding site fidelity is expected to vary according to environmental predictability, which, in turn, is expected to differ between each spatial scale. However, whether or not animals change their degree of site fidelity at different spatial scales remains unclear. We captured and released males of the terrestrial frog Pseudophryne bibronii into alternative patches within a breeding habitat and determined the extent to which site fidelity influenced individual nest-site choice. We found that males tended to return to their original patch rather than r…
Statistical check of USLE-M and USLE-MM to predict bare plot soil loss in two Italian environments
2018
The USLE-M and the USLE-MM estimate event plot soil loss. In both models, the erosivity term is given by the runoff coefficient, QR, times the single-storm erosion index, EI30. In the USLE-MM, QREI30is raised to an exponent b1> 1 whereas b1= 1 is assumed in the USLE-M. Simple linear regression analysis can be applied to parameterize both models, but logarithmically transformed data have to be used for USLE-MM. Parameterizing the USLE-MM with nonlinear regression of untransformed data could be a more appropriate procedure. A statistical check of the two suggested models (USLE-M and USLE-MM), considering two alternative parameterization procedures for the USLE-MM, was carried out for the Mass…
Application of EMI and FDR Sensors to Assess the Fraction of Transpirable Soil Water over an Olive Grove
2018
Accurate soil water status measurements across spatial and temporal scales are still a challenging task, specifically at intermediate spatial (0.1–10 ha) and temporal (minutes to days) scales. Consequently, a gap in knowledge limits our understanding of the reliability of the spatial measurements and its practical applicability in agricultural water management. This paper compares the cumulative EM38 (Geonics Ltd., Mississauga, ON, Canada) response collected by placing the sensor above ground with the corresponding soil water content obtained by integrating the values measured with an FDR (frequency domain reflectometry) sensor. In two field areas, characterized by different soil clay conte…
Diversification in evolutionary arenas - assessment and synthesis
2019
Abstract Understanding how and why rates of evolutionary diversification vary is a central issue in evolutionary biology and ecology. The concept of adaptive radiation has attracted much interest, but is metaphorical and verbal in nature, making it difficult to quantitatively compare different evolutionary lineages or geographic regions. In addition, the causes of evolutionary stasis are relatively neglected. Here we review the central concepts in the evolutionary diversification literature and bring these together by proposing a general framework for estimating rates of diversification and quantifying their underlying dynamics, which can be applied across clades and regions and across spat…