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Ecosystems with highly pulsed water supply must be better understood as climate change may increase frequency and severity of intense storms, droughts and floods. Here we collected data over 3 years (2016-2018) in the episodic wetland outflow channel (Aluize), Banhine National Park, in which the system state changed from dry to wet to dry. Field sampling included vegetation records, small-scale vegetation zoning, the seed bank and water and soil quality. The same main plant species were found in both dry and wet conditions across the riverbed of the outflow channel. We found only very few diaspores of plants in the soil after prolonged drought. In the subsequent flooded state, we examined very dense vegetation on the water surface, which was dominated by the gramineous species Paspalidium obtusifolium. This species formed a compact floating mat that was rooted to the riverbed. The Cyperaceae Bolboschoenus glaucus showed high clonal growth in the form of root tubers, which likely serve as important food reservoir during drought. Soil and water analyses do not indicate a limitation by nutrients. We outline how resident people may change the plant community structure with an increasing practice of setting fire to the meadows in the dried-up riverbed to facilitate plant regrowth as food for their livestock.
Since 1993 the southern shore of Lake Gülpe in western Brandenburg has been man-aged with Galloway cattle. This is supported by the so called "Vertragsnaturschutz" (i.e. contract nature conservation) in order to preserve the valuable, species-rich vegetation structure. This is an economically justifiable arrangement for the Galloway cattle-farmer. Permanent botanical plots were monitored in the area for four years. For most species, the observed changes in vegetation are considered as mere fluctuations on the basis of their known ecological requirements and data on hydrological dynamics during the study. Only a few species might indicate succession. A continuation of the present form of land management is recommended for the preservation of the current vegetation structure. However it is advisable to continue with monitoring of the vegetation in order to confirm the results over larger timescales. Until then the management with Galloway cattle is to acclaim as a proper treatment to preserve the southern shore of Lake Gülpe.
Since 1992 the southern shore of the Lake Gülpe in western Brandenburg is managed with Galloway cattle to preserve species, vegetation and landscape pattern. This paper presents the vegetation zones which are influenced by the water balance being the most significant and dynamic location factor in the area. Following the plots from dry to wet sites the most important plant communities are: Diantho-Armerietum, Arrhenatheretalia-Gesellschaft (-community), Leonotodon saxatilis -Potentilla anserina-community, Caricetum gracilis as well as Glycerietum aquaticae and Cypero- Samoletum. 23 endangered species were found.
Managing open habitats by wild ungulate browsing and grazing a case-study in North-Eastern Germany
(2011)
Question: Can wild ungulates efficiently maintain and restore open habitats?
Location: Brandenburg, NE Germany.
Methods: The effect of wild ungulate grazing and browsing was studied in three successional stages: (1) Corynephorus canescens-dominated grassland; (2) ruderal tall forb vegetation dominated by Tanacetum vulgare; and (3) Pinus sylvestris-pioneer forest. The study was conducted over 3 yr. In each successional stage, six paired 4 m(2)-monitoring plots of permanently grazed versus ungrazed plots were arranged in three random blocks. Removal of grazing was introduced de novo for the study. In each plot, percentage cover of each plant and lichen species and total cover of woody plants was recorded.
Results: Wild ungulates considerably affected successional pathways and species composition in open habitats but this influence became evident in alteration of abundances of only a few species. Grazing effects differed considerably between successional stages: species richness was higher in grazed versus ungrazed ruderal and pioneer forest plots, but not in the Corynephorus sites. Herbivory affected woody plant cover only in the Pioneer forest sites. Although the study period was too short to observe drastic changes in species richness and woody plant cover, notable changes in species composition were still detected in all successional stages.
Conclusion: Wild ungulate browsing is a useful tool to inhibit encroachment of woody vegetation and to conserve a species-rich, open landscape.
Sansevieria pfennigii, which to date has been a doubtful species, is confirmed as extant by a recent collection from the Lindi Region in southern Tanzania. The original description of the species, which is based on herbarium material only, is here emended based on additional observations recorded from living plants, including fruits that were previously unknown. Sansevieria pfennigii distinguishes from S. canaliculata, to which it was repeatedly assigned, by its capitate instead of elongate inflorescence, rough rather than smooth leaves, non-pungent instead of pungent leaf tips, dull green leaf colour, more delicate overall appearance, alongside other traits. The difference in inflorescence architecture indicates that these species belong to different groups within Sansevieria and are not closely related; the closest relatives of S. pfennigii are probably S. fischeri and S. stuckyi. Sansevieria pfennigii occurs on well-drained soil in forests, close to S. canaliculata populations. According to the extent of the population seen and the species' overall rarity, it is tentatively assessed as critically endangered.
'Biodiversity' is increasingly perceived as an important resource for research and conservation, but also for economy. Conservation, access and sustainable use of biodiversity (genetic resources, species, samples) are negotiated on different political levels, resulting in an internationally binding legal framework. Resulting legislation is binding for all parties involved in biological sampling, i.e. researches and (and in italics) countries, and especially applies for tissue or DNA samples and dervied products thereof. Understanding and awareness of export and import permits for biological samples is increasingly important for biologists to perform research projects legally and timely. Nevertheless, some biologists are still exporting and importing biological samples ignoring or noncompliant with national and international legislation, conventions, and regulations. Resulting difficulties may not only cause serious problems during field work, but may also delay the export, import or exchange of samples. Comprehensive a priori information regarding legal requirements helps to avoid or at least diminish potential problems. We identified four major factors facilitating export/import permits: (1) good personal (mutually trusted) contacts in the country of origin, (2) understanding and compliance with all relevant laws and regulations; (3) access to information regarding knowledge on permits, regulations and laws including their circulation within the researcher communities; and (4) access to consistent and up to date regulations