Báo cáo lâm nghiệp: "Studies (L) virus infection of diseased Quercus robur from forest stands in northern Germany " potx

... contamination of soils in forest ecosystems of the Federal Republic of Germany. Eur J For Pathol 19, 47-53 Büttner C, Nienhaus F (1989b) Virus contamination of waters in two forest ... dsRNA in diseased Quercus roburwith chlorotic ringspots and mottle, prominent dsRNA bands of 1.5 to 2.0 kbp were obtained in all 26 investigated plants...

Ngày tải lên: 08/08/2014, 18:21

... methods of calculating strength of mate- rials in non-growing structures. * Corresponding author: fourcaud@lrbb3.pierroton.inra.fr Biomechanics of trees in a forest stand 271 trunk. Inversion of stem ... applications at the stand scale. In order to characterise timber quality in Aquitaine maritime pine forests for instance, foresters often look at the stem base leaning and i...

Ngày tải lên: 08/08/2014, 01:22

... valuable in general. Moreover, industrial operations using heat treatment such as steaming or hot drying are known to change beech colour by inducing a more or less pronounced reddening and darkening. ... The lightness index (L*) ranged from 58.2 to 90.3, redness index (a*) from 6.2 to 18.7, yellow- ness index (b*) from 15.4 to 30.3, C* from 16.9 to 33.4 and H* from 50.4° to 72.5°...

Ngày tải lên: 08/08/2014, 00:22

... Hoch- sauerland (Germany) were collected in 1973 and the seeds were extracted from them in the extraction plant Wolfgang in Hessia. After cleaning, dewinging and drying, the seeds were stored there in sealed containers ... out, turning intensively green (Fig. 2). It should be pointed out that the packing (bag) was opened repeatedly during storage, causing an increase in the seed...

Ngày tải lên: 08/08/2014, 00:21

... although leaching was minimized by watering to field capacity three times a week [55]. 2.4. Plant biomass and chemical analysis At the beginning of October, in the dormancy of seedlings, 35 seedlings of each ... a ICP-IES (Perkin Elmer Optima 3000). 2.5. Sampling and identification of ectomycorrhizae (ECM) In mid of October 2003, the total remaining seedlings of each pot (approx...

Ngày tải lên: 08/08/2014, 00:22

... al. [53] for Garcinia mangostana. In addition, an increasing number of branches of young Quercus petraea and an increasing length growth of these branches with increasing Table I. Results of regression ... 163–171 © INRA, EDP Sciences, 2003 DOI: 10.1051 /forest: 2003009 Original article Growth and biomass partitioning of Fagus sylvatica L. and Quercus robur L. seedlings in...

Ngày tải lên: 08/08/2014, 01:21

... the remobilisation of winter N from first year leaves suggests that hydrolysis of storage proteins and export of amino acids may have occurred [29]. An export of winter C and N was also observed from fine roots. ... changes in content and partitioning of winter C and N in plants Winter C and N represent the amount of C and N assimilated during labeling time, part of whi...

Ngày tải lên: 08/08/2014, 01:22

... immo- bilised before thinning, increased from 0 to 83%; that of wood left on the ground decreased from 64% to 5%; and that of remaining roots left in the soil changed from 8 to 18% (Fig. 3). During the rotation, ... value of 500 g/kg (475 g/kg for beech stands, this case study) can be used without introducing a large margin of error. This was mainly explained by the existence...

Ngày tải lên: 08/08/2014, 01:22

... Percentage of increasing in soil bulk density (gcm –3 ) from post-skidding to pre-skidding for each slope class and effect of slope on soil bulk density No. of passages SC1 SC2 pre-skidding post-skidding ... rutting and forest floor removal was evaluated on a skid trail in the natural forest of north of Iran. Combination of two levels of slope < 20% (SC1) and >...

Ngày tải lên: 07/08/2014, 03:22

... Stratification of the crown was not generally successful in terms of a reduction of sampling errors. Only in combination with deletion of stem segments, a clear improvement in the precision of the ... replacement. In the present study, the effects of the choice of the auxiliary variable, of the deletion of segments, and of the stratification of the tree crown on...

Ngày tải lên: 07/08/2014, 03:22