Belarusian Polish Forest Mapping Belarusian Polish Forest Mapping

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Belarusian-Polish Forest Mapping project The best protected forest types among Polish BIFs are: upper montane spruce forests (according to available data, over 60% of BIFs of this type are protected, including ca. 9% under strict protection), alder and similar swamp forests (over 30% are protected, including ca. 4% under strict protection), and upland and lower montane coniferous forests (ca. 24% are protected, including ca. 6% under strict protection). The least protected forest types are lowland coniferous and mixed forests (predominantly pine forests) and flood-plain forests – in both forest types over 90% of BIFs are not protected by law and less than 1% is under strict protection. Lowland oak forests and mixed broadleaved forests, lowland beech forests, as well as upland and montane beech forests, have similar contributions of individual protection categories: in each of these forest types less than 2% are under strict protection, while 88% are not protected. Considering the distribution of the existent network of nature reserves in comparison to BIFs, in some cases unprotected BIFs are found a small distance from existent nature reserves. To compare the conservation value of forest stands within nature reserves, in the buffer zone of up to 2 km around the reserves, and outside the zone, a one-way analysis of variance (ANOVA) was performed for 1800 randomly selected 25-ha plots: 600 within reserves (1), 600 in their buffer zones (2), and 600 in other wooded areas (3). We analysed potential differences in contributions of forests that meet selected BIF criteria: Average age of stands more than x years (OG), At least 30 years of difference between species; average age of stands more than 80 years (STR1), At least 5 species in dominant canopy level, average age of stands more than 50 years (STR2), Presence of very old trees (STR3), Endangered vegetation types (RARE_V), Rare forestdependent species present (RARE_SP) Rare broadleaved species present (RARE_BR). The above variables were subject to principal component analysis (PCA), which, because of their strong correlation, grouped them into one variable (PCA 1). An analysis of PCA 1 revealed significant differences between nature reserves and both their buffer zones and other wooded areas (ANOVA: F=66.478; df=2; P=0.000). Post hoc Bonferroni test also showed significant differences between reserves and both their buffer zones and other wooded areas (in both cases P=0.000) and lack of significant differences between the buffer zone and other wooded areas (P=0.106). Dry and sligtly wet lowland coniferous and mixed … Moist or wet lowland coniferous and mixed forests Lowland beech forests Lowland oak forests and mixed broadleaved forests Alder forests and similar swamp forests Flood-plain forests Upland oak forests and mixed broadleaved forests Upland and montane beech forests Upland and lower montane coniferous forests Upland and montane riverine forests Upper montane spruce forests 0 100 000 200 000 300 000 400 000 Strict protection Partial protection No protection Fig. 3.18. Protection categories in individual forest types of BIFs, Poland 42
Belarusian-Polish Forest Mapping project When we used only the values of STR1 (criterion: At least 30 years of difference between species; average age of stands more than 80 years), the analysis also revealed significant differences between reserves and their buffer zones and between the buffer zones and other wooded areas (ANOVA: F=43.724; df=2; P=0.000; post hoc Bonferroni test: reserves vs. buffer zone P=0.000, reserves vs. other wooded areas P=0.000, buffer zone vs. other wooded areas P=0.028). This means that applying the structural criterion STR1, protected areas were more valuable than immediate buffer zones, which, in turn, were more valuable than other comparable forest areas (fig. 3.19). Fig. 3.19. ANOVA of variables describing three distinguished zones (1 = reserves; 2 = buffer zones; 3 = other wooded areas). A = comparison for PCA1; B = comparison for STR1, Poland The lack of significant differences between the buffer zone and other wooded areas in the analysis of the selected set of criteria may indicate that long-term forest management did not cause any increase in contributions of old forests, endangered vegetation types, and stands with rare forest-dependent species present (i.e. forests with a truly high conservation value) outside reserves. On the other hand, the significant difference in proportion of forests that meet the criterion At least 30 years of difference between species; average age of stands more than 80 years between the buffer zone and other wooded areas may attest to some preferences in forest management in buffer zones (e.g. a higher proportion of selective felling than in ‘average’ forests, which contributes to uneven age structure) and the resultant potential of those forests to increase their conservation value. This may be an important incentive to initiate creation of ecological corridors between refuges of forest biodiversity, such as forest reserves. The plan for their creation should be based on a detailed spatial analysis with the use of GIS tools, considering distances between patches of BIFs, the degree of their fragmentation, and conservation value of the areas that could be transformed into ecological corridors between BIFs. The isolation of protected areas, in combination with the fragmentation of BIFs, may result in a decline or even extinction of populations of many forest-dependent species (Hanski and Walsh 2004). Many of the species have already disappeared from areas where they used to be found because of deforestation or transformation of their natural habitats (Bobiec et all. 2005). Remaining patches of BIFs (e.g. old forests) might enable restoration of their populations at least in some parts of their former range of distribution. However, in the situation when only a few selected patches of BIFs are protected as nature reserves, and between them intensive forest management is applied (causing decline of natural features of those forest stands) this is currently unrealistic. 43
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Belarusian Polish Forest Mapping Belarusian Polish Forest Mapping

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