Báo cáo lâm nghiệp: "Excess nitrogen affects the frost sensitivity of the inner bark of Norway spruce" pdf

... between N and other nutrients in the needles; (c) the frost sensitivity is related to the concentrations of sugar and starch in the bark; (d) the concentrations of sugar and starch in the bark are ... In another study on 30–40 year-old Norway spruce in southern Sweden, the frost sensitivity of the bark and hardiness status of needles were rela- ted to...

Ngày tải lên: 08/08/2014, 01:21

... fertilizer in the aboveground part of a plant, T r – amount of nitrogen absorbed from fertilizer to the root of plants, U c – amount of nitrogen absorbed from the soil in the aboveground part of a ... aff ect the level of experimental crop yield. Be- sides, neither the content of easily available mineral forms of N nor the total quantities of the N fra...

Ngày tải lên: 07/08/2014, 10:21

... of the locality (P > 0.05). Only in the areas at the altitude of 600–700 m a.s.l. the rodent-caused damage was lower than at other localities (P < 0.05). A common characteristic of the ... initiation of an extensive research focused on monitoring the population dynamics of rodents in forest environment, their feeding behaviour and the damage they cause. At...

Ngày tải lên: 07/08/2014, 03:22

... climate are the main sources of the final error. In addition, the low presence of some tree species in the source data set negatively influenced the accuracy of the results. eo- retically, the standard ... rates of tree species situated in lower sites for the estima- tion of their future growth on the basis of ecological analogy. Both, the change in climate...

Ngày tải lên: 07/08/2014, 10:21

... pollution stress. After the pollutant concentrations in the air decreased, the main factor affecting the forest stands is the state of forest soils which shows the insufficiency of the main nutrients ... content in the samples of spruce needles Fig. 4. Ca/Al molar ratio in soil water LH – under the humus horizon, L30 – at the depth of 30 cm of mineral soil, L50...

Ngày tải lên: 07/08/2014, 10:21

... analyzed using the Kruskal-Wallis test as the nonparametric analysis of variance be- cause of the violation of the assumptions of ANOVA. Statistical analyses were carried out using the pro- gram ... 101–111 109 the most effective use of the shorter growing season at the high site. Anatomical structure of needles and shoots In the needles of different species...

Ngày tải lên: 07/08/2014, 10:21

... in theory the disease is likely to extend farther and even exceed the distribution range of the beetle. The beetle is one of the most important vectors of the disease in China, control of the ... survival of the species. Accordingly, the January isotherm rather than latitude is more useful for predicting the northern limit of the beetle distribution. Also, t...

Ngày tải lên: 07/08/2014, 16:20

... there is a need to investigate the global relevance of these concepts when applied to other spe- cies. The objective of our contribution is to research the ways of improving the accuracy of the ... Here, we applied the D m of 5 mm. The scaling factor α is defined as the ratio of the square of root diameter before bifurcation ( ) to the sum of squares of...

Ngày tải lên: 08/08/2014, 01:21

... stigmas. The conca- navalin A-peroxidase reaction allowed the visualization of 15 stigmatic and pollinic glycoproteins. Differences were observed, according to the type of cross: ... increase of its activity (one isoenzyme of isoelectric point about pH 4.2) from 6-20 h after pollination was detected only in the compatible cross. Conclusion The...

Ngày tải lên: 09/08/2014, 04:20

... strips were eligible for harvest at the beginning of the fi rst period. Of these strips, 234 were cut in the fi rst period, 271 in the second, and 279 in the third (Table 1).  e remain- ing ... by multiplying vol/ha generated from the above growth equation by the area of the unit.  e objec- tive of this study is to examine how the introduc- tion of strips in a...

Ngày tải lên: 07/08/2014, 10:21