Posted on 13/09/03 in Environment
When dealing with the major threats to the forest there are a number of factors that must be taken into account. In this report we will discuss these threats, highlighting the principle ones. We will then look at the preventive measures in place at the moment and their effectiveness. To conclude we will suggest some alternative solutions and our opinions on what are the major threats to the forest.
While not a major problem in Sumava, there have been some cases. In Sumava fires normally occur near the railways where they can than spread to the wood. Another cause of fires in the forest is a direct result of humans. Some tourists and even forest workers can act irresponsibly by smoking in the forest. The most serious fires can occur when the roots of the trees burn. To stop this happening, those controlling the fire have to dig around the area. The wind is also a major factor in the spreading of these fires. In Sweden forest fires have been tested on a small scale in protected areas and the results are promising.
LEGAL AND ILLEGAL CUTTING
One of the practices that still occurs in the Czech Republic is that specialised firms pay people to sign for ownership of the forests and then cut them down without reforesting them. Legally you can cut 1 hectare of land in the Czech Republic if you reforest it. While different countries have different legislation, there is still much room for improvement. In Sweden, for example, if you are a forest owner, you must spare 5% of the productive forest. This does not always happen though. In Sumava, the forests are cut to try to control the problem with the bark beetle.
While insects are a natural part of the ecology of the forest, with trees in artificial forests such as the spruce trees in Sumava, certain insects can cause major problems. Now we will look at the bark beetle in particular as it it a major problem in Sumava.
The Bark Beetle
While there are many species of bark beetle, the one which is found in the Sumava forest is the Ips typographus. This insect is about half a centimeter long and extremely dangerous for the spruce trees in Sumava. The adult bark beetle is black while the young are yellow. At the beginning of August every year they begin swarming. The male beetle looks for an unhealthy tree as healthy trees have a built-in defense system. While they prefer dead trees, they will move onto unhealthy ones when they are finished. The male bark beetle is attracted to the females feromone and they mate in the bark. The male bark beetle normally mates with 2 or 3 females. After they mate, eggs are laid and these are the beginnings of the corridors that are on the bark. The worms make a cocoon after burrowing and after 2 weeks they make a hole in the bark and a new young bark beetles are born. The factors which affect the bark beetle are temperature and the location of the wood. The number of species can vary and the highlands usually have one while the lowlands have two to three. The bark beetle has a lifespan of two years and under the correct conditions it can produce 100,000 offspring. This is, however the highest number of offspring that can be born and depends on many factors, especially the condition of the trees. The number of bark beetles needed to destroy a healthy tree is between about two and five hundred. When there is storm damage to a tree the beetles attack the unhealthy tree and the forestors are forced to de-bark the tree. Three is the most females that the beetle will mate with and each female has the ability to produce 60 eggs. The foresters can judge how many meters of forest that will be destroyed each year.
Clearcutting can be used as an emergency solution. Mixed forests are also a sustainable bark beetle solution.
These devices are placed in the forest between the trees. These feromone catchers have gaps between the shutters and look like blinds on a window. It works on the principle that an agragation feromone mimics the female bark beetle. However, these catchers can only catch 10% of the population of bark beetles and therefore are not very effective.
The trap tree is made up of three logs which are covered with branches. While it is a suitable measure, it is still not extremely effective at eliminating the bark beetle.
Finally, one of the greatest dangers to the forest can be a result of humans. One of the debates surrounding forests at the moment centres on how much of the forest should be allowed to be open to the public. The right kind of tourism can be fully compatible with the objective of a protected area. However, in many National Parks, this growth has affected the ecology too much. Too many tourists can, in some in cases, create serious pressure on the environment.
Prevention from the bark beetle is one of the most important things to consider when considering the threats to the forest. While cutting the forests helps in the short term, it is not a sustainable answer. Economic income is needed to influence the micro climate or else there will just be spruces again. The other species are not able to grow in the conditions of the spruces. The soil is too acidic for them. There is also a problem with the feromone catcher in that it is only 10% effective. Trap tree also is not a very effective measure. Immediately after the settlement by the bark beetle the trees must be cut and debarked to stop their offspring reproducing.
SUGGESTED POLICY FOR SUMAVA FOREST
Regular and if possible daily monitoring of affected trees. Affected trees must be cut down and debarked to prevent further outbreaks. Trees, where possible, should be left in the wood as it is extremely beneficial to the soil. Attempts should be made to plant beeches, mountain ash and maple to promote and aim at achieving a mixed forest. The spruce monoculture, although an economically viable option is not a good choice for a National park and biodiversity should be encouraged as a long term, sustainable solution.