DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 7-8/1986 str. 104 <-- 104 --> PDF |
formation of barren areas and degraded forests, which could not have been prevented by regulations, although they were already introduced in the statutes of some towns. In the second half of the last century, the lowland forests of Posavina and Podravina were subjected to intensive exploitation. As a result of the changes in the forest ecolsystems, there occurred a weakening of their stability. Civilisation and progress in technic and technology was accompanied with severe interventions by people in biosphere, primarily in the forests, and also outside them. The aforementioned caused changes in the water regime in the soil and all dependant physiological processes, and favourable climatic conditions contributed to the mass spreading of pests and diseases. Today, the main problem in forest protection in the dying out of the important and dominant species in the natural forests of oak, elm, ash, beech, fir and pine. Defoliators play an important role in this process. Thus, investigations are directed towards the discovery of effective methods for their control. A transition was made from the organic-origin preparations to organic synthetic insecticides (DDT, HCH) and organogenic phosphorous substances, which, after being in use for approximately 20 years were substituted by the biological preparations (Dipel, Bactospeine, Thuricide, etc). Recently, a transition was made to the inhibitors of chytin synthesis (diflourbenzuolor), Dimilin preparation, and the application of feromon (Pheroprax) in prognostic service; as well as in the repressive sense. Attention was paid to the integrated methods of pest control, as well as testing for the control of pathogens by fungicides and other methods of inoculation with hypovirulent strains (in Endothia parasitica). During the application of pesticides, records are made of their effect on the environment. The hypothesis of forest dying out due to the emissions is a subject open to investigation, and initial investigative steps have already been made. Prof. Dr. Ankica Pranjić Forest Management and forest Mensuration Our cultivation of forests and their evaluation was done according to special laws in the past. Besides some positive roles which those laws had in the past, they did, however, without doubt, limit the development of dendometry, fotogrametry and biometry. Meanwhile, keeping in mind today´s situation of forest here and around the world, and also the multi-purpose of the forest, the system of gathering information needs to be much larger than before. Information derived from dendometry and photogrametry is not enough on which to base the planning of forestry. Planners have to get all the information on ecologically cultivated types and establish plans of cultivation which need to be flexible and able to cope with outside influence and internal changes of the eco-system. In forming a plan of cultivation, one cultivated form of forest needs to be examined by a team of specialists from different professions. Regarding the huge amount of informa |