Báo cáo lâm nghiệp: "Water movement and its resistance in young trees of Cryptomeria japonica" pot

... Water movement and its resistance in young trees of Cryptomeria japonicaH. YahataLaboratory of Silviculture, Department of Forestry, Faculty of Agriculture, Kyushu ... University,Fukuoka, JapanIntroductionInformation about water flow resistance isessential to understanding and simulatingwater movement in trees (Yahata, 1987).There are a number of papers ... in the stem in place of Q and the gradients of water potential betweensoil and leaves, .1"’s-1> or between rootstock and leaves, dyrr-,, the resistance of...

Báo cáo lâm nghiệp:"Water relations and hydraulic characteristics of three woody species co-occurring in the same habitat" pptx

... with a maximum in autumn and a minimum in winter (between January and March).Winter temperatures often fall below 0 °C and in the coldest month(January) the mean of the daily minima is, on average, ... as of root and shoot hydraulic resistance in three field-growing species co-occurring in the same habitat i.e. Cotinuscoggygria L. (Wig tree), Prunus mahaleb L. (Mahaleb cherry) and Fraxinus ... relations of co-occurring woody plants 301that measured in May. In September, Rplant was about twice asmuch as that measured in the spring in C. coggygria and P. mahaleb and 2.4 times more in F....

Báo cáo lâm nghiệp:"Stand history and its consequences for the present and future dynamic in two silver fir (Abies alba Mill.) stands in the high Pesio Valley (Piedmont, Italy)" potx

... coppicing of shade-intolerant broadleaves prevented them from competing withthe silver fir and from reaching the dominant, codominant and intermediate layers, thus making it possible to maintain ... establishment of pioneer species and of early-seral shade-intolerant species,historical data of logging. The stands investigated are relatively young; in the past 70 years some periods of heavy logging ... five-year interval of 1935; indeed,intense logging was carried out in the Buscaié forest duringthat interval, and in the plot 1 more than 24% of the silver firs(probably reserves left by cutting)...

Báo cáo lâm nghiệp: "Neuroptera, Raphidioptera and Mecoptera assemblages inhabiting young spruce (Picea abies) forests: dominance structure and seasonal activity patterns" docx

... de-ciduous trees. H and V (2002) ob-served the peak of its activity in spruce forests of Paskovský les and Loucký les at the end of May in 1998. e delay of its flight activity in highlands, ... regularly occurring in coniferous trees. We recorded this species from the mid of May to the mid of August with the peak of its activ-ity at the beginning of July.e flight activity of snake fly Phaeostigma ... a.s.l.) in very young spruce forests (10–20-year-old). All Malaise traps were installed in small forest clearings, minimally 30 m inwards the forest. e forest clearings are covered mainly by...

Báo cáo lâm nghiệp: "ce nucleation and frost resistance of Pinus canariensis seedlings bearing needles in three diﬀerent developmental states" pptx

... frost resistance of expanding current-yearneedles of the Canary Island pine and subalpine evergreentimberline conifers of continental Europe suggest that frosthardening during sprouting and ... formation and E2, released during intracellular freez-ing, were recorded on 1 year old needles of potted seedlings of P. c a -nariensis during controlled freezing treatments (cooling and thawingrates: ... needles in seedlings of P. canariensis in diﬀerent stages of development:currently expanding, fully expanded, and 1 year old needles.Some seeds of P. canariensis may germinate in autumn [16]and...

Báo cáo lâm nghiệp: "Tree density and site quality inﬂuence on Pinus halepensis Mill. reproductive characteristics after large ﬁres" pdf

... Spain (Fig. 1). Two of these ﬁresoccurred in the provinces of Barcelona and Tarragona (NE Spain),where 50 000 ha and 12 500 ha were burned, respectively, and theother two in the provinces of ... diﬀerences depending on whetherseeds are from serotinous or non-serotinous cones. Pine prove-nance must also be regarded as an important factor in deter-mining germination [9].The increase in forest ... factors, including size, age and tree density [24]. In one strategy, seeds germinate from non-serotinous cones un-der warm and dry weather conditions, and in the other, theydevelop from serotinous...

Báo cáo lâm nghiệp: " Nutritive stress and cytokinin status in Norway spruce seedlings (Picea abies L. Karst.)" ppsx

... cytokinin promotedeffects could then cause an increased flux of auxin from theshoot to the root. As this hypothesis seems compatible with thefinding of increased levels of cytokinins in needles ... thecytokinin content in the shoot. In discussing the elevated content of cytokinin ribosides in shoots of seedlings grown on STRESS-AlCl3 – and STRESS-NAA-medium, we assume that the increased ... reduction in the rate of metabolisation of isopentenlyadenosine. We assume that the increased cytokininlevels in shoots of stressed seedlings could in addition to theincreased number of root...

Báo cáo lâm nghiệp: "Geographic variation and bud dormancy in seedlings (Fagus sylvatica L)" potx

... LD alsoplayed a role in removing dormancy and/ orinitiating growth.The findings of experiment 3 supportedthis hypothesis. In the Casentino seedlingsa LD reduced the thermal ... seedlings had been transplanted at thebeginning of autumn in the year of germination(1987) to pots (diameter 18 cm, depth 30 cm)containing 50% fir and chestnut loam and ... and turf and 50% sand; they were then maintained in thenursery, with a plant density of 30 plants/m2, in Florence, during the winter and the followinggrowing season....

Báo cáo lâm nghiệp: "Biomass, litterfall and nutrient content in Castanea sativa coppice stands of southern Europe" ppt

... all chest-nut trees of the Mediterranean area. Dif-ferences in aboveground stand biomassresulted mainly from variations in standdensity of individual trees and their reparti-tion ... Mediterranean.Biomass of individual trees, abovegroundstand biomass, their yearly increments and nutrient contents were studied in coppices of Spain, Italy and France. Litterfall and nu-trient ... Martin trees. In contrast, the phos-phorus content seemed higher in trunks of the Spanish stand than in the two Italianstands. For the branches, generally havingyounger...

Báo cáo lâm nghiệp: "Polyamines during somatic embryo development in Norway spruce (Picea abies [L.])" potx

... level of spermidine (M et al. 1999). A high level of putrescine was determined in the pro-embryogenic tissue of Picea rubens, while spermidine was predominant during the stages of embryo ... ecotype of Norway spruce.Contents of free polyamines (putrescine, spermi-dine, and spermine) were determined in diﬀerent developmental stages of Norway spruce somatic embryos.MATERIALS AND METHODSInduction ... repre-sent the dominant polyamine in somatic embryos of conifers. Whereas the development of both somatic and zygotic embryos of Pinus radiata was charac-terized by a high level of Spd and its concentration...

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