Browsing by Subject "NATURA 2000"
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Publication Ableitung von Restitutionspotenzialen als Entscheidungshilfe bei der Umsetzung von Moorschutzprogrammen(2005) Röhl, Markus; Böcker, ReinhardAs one of the last peatland-rich states of Germany, Baden-Württemberg possesses no self-standing, conservation program to protect its peatlands. Therefore, after consideration of the state administration, a strategy should be created in the next few years for a Baden-Württemberg peatland protection concept. With this in mind, a methodology for the derivation of peatland restitution potential was developed that can direct the future implementation of such a strategy. The exemplary methodology was developed for the nature conservation area ?Schwenninger Moos?, a medium sized former raised bog strongly disturbed by peat digging and agricultural amelioration. The results were applied to the entire surrounding bio-geographical region, the Baar and the Baaralb. Through this verification of the methodology, significant shortfalls in the state-wide dataset could become evident. As the basis of the evaluation of the restitution potential, data concerning the water level, trophy, and species and biotypes in Schwenninger Moos were collected. The water level of Schwenninger Moos was documented through 34 water gauges, the data from which was analysed through various methods. The half-year median and the combined examination of amplitude, average, and minimum values proved especially suitable for the characterisation of the sites. The trophic classifications of the sites were compared through measuring the principal nutrient levels, pH and conductivity values, as well as the C/N ratio. The vegetation of the investigation area was mapped and the results were subsequently compared to the mapping of biotypes of Baden-Württemberg, the mapping performed in the frame of Natura 2000, as well as that of indicator species groups. The mapping of indicator-species groups proved particularly suitable for the appraisal of the current status of a moor complex. The available data on the mires from the peatland register of Baden-Württemberg were somewhat old (40 years). Therefore these data were verified through comparison-boring and continued measurement by means of georadar. Significant differences arose in a number of comparisons between the peatland register and the author?s investigations with respect to the positional accuracy and the stratum sequence. The derivation of the restitution potential was carried out through the combination of three separate assessments: rewetting-possibility, biotic potential, and conversion potential. These three factors were derived through verbal-argument and brought together in a simple, five-step classification. The rewetting-possibility of an area is the main factor determining the restitution, and it depends considerably on drainage systems, topography, condition of the peat, and the water level. The biotic potential consists of the presence of peat-producing plants and the effects of rewetting on populations of endangered species. The conversion potential is essentially dependent on the dominant uses, ownership and social framework. The methodology was applied to altogether 34 peatland complexes of the Baar and Baaralb. The identification of these locations was only possible by a laborious combination of the peatland register, pedological cartography and conservation-oriented publications. It was found that the peatland register exhibited substantial deficits regarding the classification of small and shallow-layered locations in the Baar. Data concerning vegetation and the occurrence of animals and plants were available for the derivation of the restitution potential. However, some of these proved too old and/or too inaccurate or not spatially verified. Little to no data were present as to the water balance and drainage systems. Only three of the 34 locations exhibited a high restitution potential. 23,5% were classified as having moderate restitution potential; most of these sites are already under protection as nature conservation sites. A slight restitution potential was present in a total of 38.2% of the mire complexes, which consist mostly of small-scale spring mires and intensively agriculturally and silviculturally used locations. Likewise, 29.4% of the moorlands exhibited no more restitution potential. For the implementation of a state-wide mire protection program in the context of the investigation, the substantial deficits were pointed out and recommendations for action were formulated. Primarily, an updated and complete peatland register must be available. Furthermore, vegetation and endangered species maps of the entire peatland complexes protected as high conservation value areas should be available. It is in this regard that a system of indicator vegetation units of south German mires is to be aimed for, as is employed in northeast Germany, for example. Lists of priority sites should be made by regional teams of experts for the respective moor regions or administrative districts.Publication Changing botanical composition of species-rich meadows through variation of management(2022) Boob, Meike; Lewandowski, IrisSpecies-rich hay meadows are threatened habitats for many plant and animal species. The biomass of these meadows has traditionally been used as forage for extensively kept ruminants. During the last decades, their habitat quality and area have been declining. On the one hand, the decline of species-rich hay meadows could be caused by increased fertiliser use as well as earlier and more frequent cutting. On the other hand, a reduction or abandonment of agricultural usage reduces their floristic diversity. This reduces important ecosystem services provided by these habitats, e.g. pollination. Therefore, benchmarking data on botanical composition and biomass is needed to estimate effects of different fertilisation and cutting regimes. This thesis aims at developing recommendations on how to manage species-rich hay meadows in order to conserve habitat functions and to enable agronomic usage at the same time. More specifically, management effects on botanical composition, biomass quantity and quality were investigated in a field trial running from 2013-2018. In this field trial, twelve different treatments were tested in a randomised block design at two sites in southern Germany. The different treatments consisted of a combination of three fertilisation levels (none, PK and NPK) and four different dates of first cut. The cutting date variants were chosen according to the phenology of dominant grasses before, at the beginning and at the end of flowering as well as a late cut at the seed-ripening stage. Both sites were species-rich hay meadows and each plot was fertilised annually and cut twice a year during the six-year field trial. The first study investigates changes in botanical composition. The number of vascular plant species did not significantly change after four years of fertilisation or cutting-date treatments, but botanical composition was affected significantly. The proportion of grasses was promoted by NPK fertilisation at both sites and by early cutting dates at one site only. Forbs were replaced by grasses because this site was dominated by the annual species Rhinanthus alectorolophus, a hemiparasite relying on generative reproduction. The second study addresses the question if living conditions of small plant species are affected by changed management. It was shown that shading reduced the proportion of small plant species due to the increased dry matter yield (DMY) caused by NPK fertilisation. It was concluded that annual NPK fertilisation containing 35 kg N ha-1 impairs the habitat function of species-rich hay meadows and, in the long term, excessive fertilisation could lead to reduced species numbers. Results of the third study revealed that although the date of first cut plays an important role in determining chemical composition of biomass, there is flexibility of choice at later cutting dates. Between the flowering and the seed-ripening stage, there were no significant differences in forage quality. However, late-cut hay is suitable as exclusive feed for horses only. Therefore, an early cut is recommended for use as biogas substrate and to be included into rations for extensively kept ruminants. In conclusion, general patterns of management effects were detected: Annual NPK fertilisation decreases the habitat quality of species-rich hay meadows. Based on the three studies presented in this thesis, the date of first cut in perennial plant communities should be handled more flexibly. This would benefit farmers, because higher forage qualities can be achieved. However, it was shown that there are site-specific effects. Plant communities containing annuals can be severely affected by advanced cutting dates, and the phenology at the date of first cut is crucial for the survival of these species. Interacting negative effects of fertilisation and cutting date on habitat quality suggest that the combination of late cutting date and NPK fertilisation should be avoided. Therefore, the best management at whole-farm scale appears to be a rotational cut and an extensive fertilisation of single meadows.Publication Evaluation der Richtlinienkonformität von Verträglichkeitsprüfungen nach Artikel 6 Flora-Fauna-Habitat-Richtlinie in der Planungspraxis(2011) Matthäus, Gunther; Dieterich, MartinThe dissertation presents findings of a study on the practical implementation of the Habitats Direktive, Art. 6 (3). The formal und methodological quality of 50 appropriate assessments according to the Habitats-Direktive was analysed. Overall, a solid or even high to very high level of quality was found. Only few assessments exhibited serious shortcomings or mistakes with relevant effects on the finding of the assessments. These shortcomings coud be avoided by the introdiktion of binding quality standards.