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51.
New Forests - In seedling-based reforestation operations, seed source is known to be an influential variable affecting outplanting success. Adaptive variation among seed sources may also be an...  相似文献   
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In this study, the information needs of non-industrial private forest owners in Finland, after logging operations, were investigated. The study was carried out as an online survey in 2017. The survey was targeted at non-industrial private forest owners who had sold their timber during the previous 10 years (2008–2017) and whose email addresses were in the customer relationship management system of a large wood procurement company in Finland. A response link for the survey was successfully sent to 31,988 forest owners, of whom 3323 replied (response rate: 10.4%). The final study data included 3284 non-industrial private forest owners. The results of the study, which need to be interpreted cautiously due to the low response rate, showed that the forest owners want better-quality reporting after logging operations. Furthermore, the results suggested that gender, age, education, occupational status, place of living, size of, and access to, forest property, and length of, and objectives for, forest ownership have a significant effect on their information needs. Younger, highly-educated, female, urban-living and multi-objective forest owners with larger forest holdings and short forest ownership tenures desired more information. Particularly, the respondents conveyed that they would like more and better information about thinning harvesting result. The results also indicated that when different groups of forest owners call for certain information, there is a need for producing different types of reports after logging operations for different forest owner segments.

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Ohne Zusammenfassung f. f?chf. Dberforftmeifter. f. bahr. Regierungs- und Forftrath von Mürzburg. f. preuk. Dberforftmeifter aus Breslau. f. f?chf. Dberforftmeifter. f. bahr. Regierungs- und Forftrath von Augsburg. f. bahr. Regierungs- und Forftrath aus Regensburg. Dberj?germeifter von Braunfchweig. f. bahr. Regierungs- und Forftrath aus München. f. f?chf. Dberf?rfter. f. f?chf. Dberforftmeifter. f. f?chf. Dberforftrath. herz. braunfchweig. Forftmeifter von Blanfenburg. Direftor der fürftlich Cfterhazh’fchen Herrfchaft Spoly Parsto. fürftl. fondershauf. Dberfortmeifter. f. bahr. Redierf?rfter don Schmarzenbach. f. preuk. Dberf?rfter. f. f. Forftrath aus Brekburg. f. preuk. Dberf?rfter von Altruppin. f. hann?v. Forftmeifter von Rienburg. Forftmeifter in preuk. Schleften. f. preuk. Dberforftmeifter von Berlin. herz. aftenburg. Dberfortmeifter. f. preuk. Dberf?rfter. f. f?chf. Dberf?rfter. f. ruff. Forftfomiff?r aus Marfchau. f. preuk. Forftinfpeftor. f. f?chf. Forftinfpeftor. grokh. meimar. Forftinfpeftor von Martfuhl. f. mürttb. Dberf?rfter und Brofeffor aus Hohenheim. f. hannov. Forftmeifter aus Hammeln. Dberforftmeifter aus Sotha. herz. altenburg. Dberf?rfter aus Hummelshain. herz. altenburg. Revierf?rfter aus Milchwig. herz. altenburg. geheimer Finanzrath und Dberforftmeifter. herz. altenb. Dberforftmeifter aus Hummelshain. grokh. f?chf. geheimer Dberforftrath aus Qifenach. herz. naffau. Dberforftrath aus Miesbaden. grokh. heff. Dberforftfefret?r aus Darmftadt. f. f?chf. Dberforftmeifter.  相似文献   
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Digestates vary in composition and studies regarding their impact on C and N dynamics in soils are scarce. The objective was to analyse the C and N dynamics of digestates originating from various substrates applied to a sandy Cambisol and a silty Anthrosol. In three laboratory experiments (4–6 weeks), the effects of digestate properties, N rate and water content were tested. Averaged over both soils, 21% of the C supplied was emitted as CO2. Potential NH3 emissions during the first week ranged between 6% and 12% of NH4+ present in the digestates. The emission factors in the sandy Cambisol were on average 1.2 and 2 times higher for CO2 and potential NH3, respectively, compared to the silty Anthrosol. Similarly, net nitrogen mineralization in the sandy Cambisol was approximately twice the N mineralized in the silty Anthrosol. Net nitrification was not influenced by soil texture or different digestates, but increased with increasing application rates and had highest values at 75% of water holding capacity. Our results indicate that the type of substrate input for anaerobic digestion influences the properties of the digestate and therefore the dynamics of C and N. However, soil texture can affect these dynamics markedly.  相似文献   
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Finnish isolates of Beauveria bassiana (8 isolates), Metarhizium anisopliae (7), Tolypocladium sp. (2), Paecilomyces farinosus (2), P. fumosoroseus (1), Steinernema feltiae (3) and Bacillus thuringiensis ('Muscabac') were tested for efficacy against mixed populations of Delia radicum and D. floralis under field conditions in 1986–90. All pathogens were applied preventatively, the fungi as aqueous conidial or mycelial suspensions, dry conidia or dry mycelial powder. In only two of the nine experiments did B. bassiana or M. anisopliae give some control. In 1986, B. bassiana SF85–2 and Tolypocladium sp. SF85–4 (both at rate 1.2 x 109 conidia plant‐ 1), and ‘Muscabac’ (25 g 1?1, 1 dl plant?1) reduced the number of pupae by 80%, 60% and 50%, respectively, as compared with untreated and chemical (isophenphos) controls. In 1990, M. anisopliae SF86–39 at rate 1.6 x 109conidia plant?1 and 1.5 x 108 CFU plant?1 and S. feltiae SFS‐22 (35000 plant?1), increased the yield of cauliflower 2.2, 1.8, and 2.3‐fold, respectively, as compared with the untreated control, but these yields were only 19%, 15% and 19% of those of the chemical (diazinon) control. Paecilomyces isolates were ineffective in the 1986 experiment in which they were included. Our results suggest that it is difficult to find efficient control agents among the fungal and nematode species tested for use as biopesticides against cabbage root flies, but that the potential of M. anisopliae against these pests deserves further study.  相似文献   
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