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71.
European Journal of Forest Research - 相似文献
72.
Fr. 《Journal of pest science》1937,13(7):92
Ohne Zusammenfassung 相似文献
73.
74.
Fr. 《Journal of pest science》1937,13(7):92
Ohne Zusammenfassung 相似文献
75.
Fr. 《Journal of pest science》1931,7(5):57-58
Ohne Zusammenfassung 相似文献
76.
77.
78.
Ewald Frömming 《Journal of pest science》1955,28(1):7-9
Ohne Zusammenfassung 相似文献
79.
Mathieu Jonard Frédéric André François Jonard Nicolas Mouton Pierre Procès Quentin Ponette 《Annals of Forest Science》2007,64(2):141-150
Total Soil Respiration (TSR) was measured in pure and mixed stands of oak and beech and was partitioned into two contributions using the forest floor removal technique: Mineral Soil Respiration (MSR) and Forest Floor Respiration (FFR). In addition, laboratory incubations of the forest floor and the Ah horizon were performed to evaluate the heterotrophic respiration and the DOC production of these horizons. The relationships between soil temperature and the various soil respiration contributions in the three stands were compared using Q 10 functions. In situ, significant differences (α = 0,05) between stands were observed for the R 10 parameter (respiration rate at 10 °C) of the TSR, MSR and FFR contributions, while only the temperature sensitivity (Q 10) of TSR was significantly affected by stand composition. The effect of soil water content was only significant on MSR and followed different patterns according to stand composition. Under controlled conditions, the R 10 of the forest floor and of the Ah horizon varied with stand composition and the Q 10 of the forest floor decreased in the order: oak (2.27) > mixture (2.01) > beech (1.71). 相似文献
80.
Stéphanie Mariette Emilie Balsemin Solenn Stoeckel Muriel Tavaud Hervé Le Bouler Frédérique Santi Michel Verger 《Annals of Forest Science》2007,64(5):533-539
Parents and progenies genetic diversity, and male and female contributions to the seed crop were assessed in three experimental Prunus avium seed orchards. Collected data were used to compare different effective population sizes, based on phenological, seed crop and paternity analysis. Our results did not show any difference of genetic diversity between parents and progenies. A limited pollen pollution was detected. We showed that distance and coflowering among clones had a significant effect on effective pollination, and a significant effect of the production of flowers was revealed in one of the seed orchards. Our study also revealed a quite low number of effective size of fathers per mother, but high effective sizes of mothers, fathers and parents at the level of the seed orchard. Finally, the calculation of effective size of mothers, fathers and parents was not highly modified when having the complete information based on the paternity analysis. 相似文献