Stock of seeds in soil of fir groves bilberry

It is known that the recovery of the vegetation may be due to the seeds that come from the outside or contained in the soil bank of plant communities [4]. The number of the seeds in the forest floor, even in the lean years of 9-27 pc. per 1 m2, and in the harvest - 364-910 units per 1 m2. [2] However, data on the stock of viable seeds in the soil of spruce spruce blueberry Arkhangelsk region is very small, so this issue is very important.

Studies were conducted in the indigenous spruce blueberry in the Primorsky district of Arkhangelsk region (northern taiga subzone). The research was bilberry spruce IV quality class, the class of age are maturing and ripe. In the structure there are larch and birch. The undergrowth is presented juniper, wild rose and red currant.

In eight trial areas have been studied by the natural regeneration of spruce undergrowth translation (accounting for 30 sites on 4 m2 each were counted undergrowth by category size and condition), and the samples were taken from the litter and soil metal prism with sides 5 cm Prism dug into the soil before 10 cm and then separated the litter and soil samples were separated into layers: 0-5 and 5-10. Each litter sample thickness was measured with a ruler to the nearest 0.1 cm in 5 replicates. The method of manually sorting the seeds was selected [5, 6]. We took into account only the basic seeds of trees that make up the stand. This spruce, larch and birch. The species of seeds was determined by the determinant [1, 7], and the viability of the seeds of spruce and larch - by flotation. Birch seed viability was not determined due to the fact that birch seeds are difficult to separate from the lionfish.

The studies found that the number of the trustworthy regrowth category perfectly trustworthy (BB) and a benign defect (DB) required for the successful resumption is at an insufficient level. Therefore, the resumption of the stand is poor, because the number of young growth of less than 4.6 million units / ha. [3] (Pic. 1).

Studies have shown that quantitative stock of seeds of woody plants in the soil spruce blueberry is high. However, the percentage of viable seeds is very low or non-existent (Pic. 2).

Рис. 1 Количество благонадёжного подроста на пробных площадях.

Ель

Число жизнеспособных семян

Общее число семян

Рис. 2. Supply of seeds of tree species in soil and litter.

According to the number of the seeds in the soil is dominated by the spruce seeds from 100 to 760 per m2. In second place - birch seeds in the soil of 60-360 per m2. Larch seeds less likely, their number is 60-280 per m2. The number of viable seeds eaten is 20-80 per m2, larch - 20-60

per m2. Such amount of seed is not enough for a successful resume. Therefore, the amount of undergrowth and the explored areas is insufficient. The bulk of the seeds in the spruce forests are concentrated in the upper layers of the litter ((93-100% of the total number of seeds). Ibid, and there is a large mass of viable seeds. (Fig. 3. Contents of seeds of tree species in the litter and the mineral horizon)).

%

Ель

Лиственница

Берёза

Подстилка 0-5 см почвы

In the upper layer of the mineral

Лиственница

found a small amount of the seeds of all species (0-7% of the total number of seeds), but they were not viable. It can be assumed that they were here to collect random samples of the soil and litter. In the deeper layers of the soil in the spruce blueberry seed stock not. The low content of the viable seeds in the soil ripe spruce could be explained by the fact that with age, the ability of trees to produce enough seeds is reduced, and it can be assumed that the spruce forms only a temporary seed bank, in which the seeds remain viable for a short time.

The relationship between the number of the

seeds of spruce and fir saplings expressed logorifmicheskoy curve (Fig. 4). In the figure, each point represents the average of 4-6 observations. Correlation analysis showed that the relationship between these indicators closely, curved (correlation coefficient is 0,71 ± 0,10; reliability - 7.0; curvilinear figure - 0.43).

Рис. 4. Зависимость количества благонадёжного подроста ели от

количества семян в почве

According to the research, the following conclusions:

• a.    the number of the trustworthy spruce in the spruce blueberry is insufficient for a successful resumption;

• b.    supply of spruce seeds in the soil and litter spruce blueberry was alone sufficient to create the necessary for the resumption of spruce saplings (100-760 pcs. / m2), if it were not for the low number of viable seeds - 20-80 per m2;

• c.    the number of the viable seeds in the larch litter and the mineral soil layer is also low and is 20-60 per m2;

• d.    most concentrated in seed upper litter. In mineral soil horizons indigenous spruce blueberry seed is very small or non-existent. The number of the seeds decreases with the advance deep into the soil, as well as in the mineral layers is no viable seeds of all the studied tree species;

• e.    trustworthy relationship between the number of young spruce and reserve seeds curved, strong (correlation coefficient of 0,71 ± 0,10; reliability - 7.0; curvilinear figure - 0.43).

On the picture: blueberries. URL: