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1.
Foltête Jean-Christophe Savary Paul Clauzel Céline Bourgeois Marc Girardet Xavier Sahraoui Yohan Vuidel Gilles Garnier Stéphane 《Landscape Ecology》2020,35(5):1053-1053
Landscape Ecology - In the original publication of the article, the sixth author name has been misspelt. The correct name is given in this Correction. The original article has been corrected. 相似文献
2.
Ghislain Vieilledent Benoît Courbaud Georges Kunstler Jean-François Dhôte 《Annals of Forest Science》2010,67(3):305-305
Question
Tree mortality can be modeled using two complementary covariates, tree size and tree growth. Tree growth is an integrative measure of tree vitality while tree diameter is a good index of sensitivity to disturbances and can be considered as a proxy for tree age which may indicate senescence. Few mortality models integrate both covariates because classical model calibration requires large permanent plot data-sets which are rare. How then can we calibrate a multivariate mortality model including size and growth when permanent plots data are not available?Location
To answer this question, we studied Abies alba and Picea abies mortality in the French Swiss and Italian Alps.Method
Our study proposes an alternative semi-parametric method which includes a random sample of living and dead trees with diameter and growth measurements.Results
We were able to calibrate a mortality model combining both size-dependent and growth-dependent mortality. We demonstrated that A. alba had a lower annual mortality rate (10%) than P. abies (18%) for low growth (< 0.2 mmyear?1). We also demonstrated that for higher diameters (DBH ≥ 70 cm), P. abies had a higher mortality rate (0.45%) than A. alba (0.32%).Conclusion
Our results are consistent with the mechanisms of colonization-competition trade-off and of successional niche theory which may explain the coexistence of these two species in the Alps. The method we developed should be useful for forecasting tree mortality and can improve the efficiency of forest dynamics models. 相似文献3.
Zane Kalvīte Zane Lībiete Ivars Kļaviņš Arta Bārdule Kārlis Bičkovskis 《Scandinavian Journal of Forest Research》2021,36(1):1-14
ABSTRACT Despite near-extinction in the nineteenth century, after efficient restoration measures the population of Eurasian beaver (Castor fiber L.) in Latvia currently is viable and growing. While the ecological effect of the species on water quality and biodiversity is generally positive, the high number of animals in production forests often creates challenges for management. Drainage ditches are among the most favoured habitats of beavers resulting in flooded stands, reduced tree growth and economical losses. The aim of the study was to evaluate the chemical properties of water in forest drainage ditches, affected by beaver activity, and their changes after the dam removal. Chemical composition of surface water in ditches was analysed in sampling points above dam, below dam and in the ditch itself after removal of the dam; results compared to pristine beaver site nearby on a small stream. Results did not show significant differences between concentrations above and below dams. After removal of the dams, significant increase in DOC, N-NO3 -, N-NH4 + and TSS concentrations and significant decrease in TP concentrations were observed in some of the sites. Observed concentrations of all measured parameters were significantly lower in pristine beaver site than in beaver sites on drainage ditches. 相似文献
4.
Context
Landscape graphs are widely used to model connectivity and to support decision-making in conservation planning. Compartmentalization methods applied to such graphs aim to define clusters of highly interconnected patches. Recent studies show that compartmentalization based on modularity is suitable, but it applies to non-weighted graphs whereas most landscape graphs involve weighted nodes and links.Objectives
We propose to adapt modularity computation to weighted landscape graphs and to validate the relevance of the resulting compartments using demographic or genetic data about the patches.Methods
A weighted adjacency matrix was designed to express potential fluxes, associating patch capacities and inter-patch distances. Eight weighting scenarios were compared. The statistical evaluation of each compartmentalization was based on Wilks’ Lambda. These methods were performed on a grassland network where patches are documented by annual densities of water voles in the Jura massif (France).Results
The scenarios in which patch capacity is assigned a small weight led to the more relevant results, giving high modularity values and low Wilks’ Lambda values. When considering a fixed number of compartments, we found a significant negative correlation between these two criteria. Comparison showed that compartments are ecologically more valid than graph components.Conclusions
The method proposed is suitable for designing ecologically functional areas from weighted landscape graphs. Maximum modularity values can serve as a guide for setting the parameters of the adjacency matrix.5.
6.
7.
Uroy Léa Alignier Audrey Mony Cendrine Foltête Jean-Christophe Ernoult Aude 《Landscape Ecology》2021,36(9):2487-2504
Landscape Ecology - Landscape connectivity plays a key role in determining the persistence of species inhabiting fragmented habitat patches. In dynamic landscapes, most studies measure connectivity... 相似文献
8.
9.
Zusammenfassung 490 Sippen von 21Aegilops-Arten wurden in den Jahren 1980 bis 1982 unter Freilandbedingungen mit künstlicher Infektion auf Resistenz gegenüber dem Erreger der Halmbruchkrankheit des Getreides,Pseudocercosporella herpotrichoides (Fron) Deighton geprüft. Außerdem erfolgte an ausgewählten Sippen die Prüfung der Jungpflanzenanfälligkeit im Phytotron. Unter denAegilops-Mustern erwiesen sich im Freiland 31 Herkünfte als resistent bzw. schwach anfällig. Im einzelnen handelte es sich um Vertreter der ArtenAe. ventricosa, Ae. triuncialis, Ae. kotschyi, Ae. bicornis, Ae. columnaris, Ae. lorentii, Ae. peregrina, Ae. geniculata, Ae. speltoides, Ae. crassa undAe. tauschii. Die im Jungpflanzenstadium geprüften 7 Sippen, 3 vonAe. ventricosa und je 1 vonAe. bicornis, Ae. kotschyi undAe. lorentii, waren ebenfalls resistent bzw. schwach anfällig.
TestingAegilops species for their reaction toPseudocercosporella herpotrichoides (Fron) Deighton
Summary From 1980–1982 490 accessions out of 21Aegilops species were tested in a field trial with artificial infection regarding their resistance toPseudocercosporella herpotrichoides (Fron) Deighton in cereal crops. Simultaneously, selected accessions were checked for their susceptibility in the seedling stage under controlled conditions in the phytotrone. Among theAegilops samples 31 accessions proved to be resistant or only slightly susceptible. This refers toAe. ventricosa, Ae. triuncialis, Ae. kotschyi, Ae. bicornis, Ae. columnaris, Ae. lorentii, Ae. peregrina, Ae. geniculata, Ae. speltoides, Ae. crassa andAe. tauschii. The accessions checked in the seedling stage, i. e. 3 ofAe. ventricosa and 1 ofAe. bicornis, Ae. kotschyi andAe. lorentii, showed also resistance or only low susceptibility.
Aegilops Pseudocercosporella herpotrichoides
1980–1982 . 490 21 Aegilops Pseudocercosporella herpotrichoides (Fron) Deighton. , . Aegilops 31 ; ¶rt; Ae. ventricosa, Ae. triuncialis, Ae. kotschyi, Ae. bicornis, Ae. columnaris, Ae. lorentii, Ae. peregrina, Ae. geniculata, Ae. speltoides, Ae. crassa, Ae. tauschii. , , Ae. ventricosa Ae. bicornis, Ae. kotschyi, Ae. lorentii .相似文献
10.
S P Swanson A M Dahlem H D Rood L M C?te W B Buck T Yoshizawa 《Journal of the Association of Official Analytical Chemists》1986,69(1):41-43
A gas chromatographic method is described for the determination of deoxynivalenol (DON) and its metabolite DOM-1 in milk. Milk samples were extracted with ethyl acetate on a commercially available disposable extraction column, followed by hexane-acetonitrile partitioning. Final purification was accomplished on a reverse phase C-18 cartridge. The trimethylsilyl ether (TMS) derivatives of DON were prepared, chromatographed on an OV-17 column, and quantitated with an electron capture detector. Chromatography of the TMS derivatives of milk extracts was compared to that of the corresponding heptafluorobutyryl derivatives. The limit of detection using TMS derivatives was 1 ng/mL for both toxins with recoveries averaging 82% +/- 9% at 2.5 and 10 ng/mL milk for DON and 85% +/- 6% at 10 ng/mL for DOM-1. 相似文献