Alpine grasslands harbour species-rich communities of plants and invertebrates. We examined how environmental variables and anthropogenic impact shape species richness and community structure of terrestrial gastropods in alpine grasslands in the Val Müstair (Eastern Alps, Switzerland). Gastropods were sampled using a standardised method at 76 sites spanning an elevation range from 1430 m to 2770 m. A total of 4763 specimens representing 52 species were recorded. Correspondence analysis based on presence/absence data revealed that the grassland gastropod community was structured in a complex way with elevation, wetness, grazing intensity and inclination of the sites as key factors, while abundance-based analysis identified the importance of the elevation and wetness of sites. Generalized linear model showed that species richness decreased with increasing elevation and increased with increasing soil pH. The grassland gastropod communities were characterized by a high beta diversity, as indicated by the SDR-simplex analysis. Species-specific traits of gastropods showed sensitivity to the environmental characters of the sites, as shown by a fourth-corner analysis.
Authors:M. Cooper, P. Clarke, W. Robertson, I. McPharlin, and R. Jeffrey
Sandy soils of the coastal plain area of Western Australia have poor phosphorous retention capacity which leads to pollution of surface water bodies in the region. Application of bauxite mining residues (termed red mud) to vegetable and crops has been proposed as a solution to increase the phosphorous and water retention and thereby reduce the leaching of nutrients. The thorium and radium-226 concentrations in the red mud residues are in excess of 1 kBq/kg and 300 Bq/kg, respectively. Potentially, the use of these residues on agricultural land could result in increased levels of radionuclides in food crops grown in amended soils. The transfer of long-lived radionuclides of both the natural thorium and uranium series to a variety of vegetable crops grown under controlled conditions is investigated. The effects of varying the rates of application of red mud and phosphate fertilisers on radionuclide uptake are studied. It has been shown previously that fallout caesium-137 in sandy soils of the region transfers readily to food and grazing crops. Some of the parameters which influence that transfer are also examined.
Puszta is a widely known phenomenon that primarily denotes a deserted countryside and not the flat areas, vegetation, cattle grazing and some picturesque landscape items that are usually associated with. In Southern Transdanubia, a borderline during Ottoman rule for 143 years, settlement desertion became a crucial and overwhelming factor from 1543 to 1686. My paper addresses the age of reorganization (1686–1720), right after the Ottomans were defeated, and focuses on land use and the general appearance of the land. There are two major views on this situation. Some historians hold that the elaboration took place in a scarcely populated and “wild,” natural area, thus the process of colonization was inevitable. Meanwhile, other scholars who worked with local archival sources have pointed out that plenty of families survived there whose livelihood changed during the Ottoman occupation but they filled the land with human activities. This resulted in a different type of land structure, which was far from the so-called medieval landscape.
In my paper I follow the second theory and depict the landscape in a minor area on the basis of archival data. I analyze the practices of land use in order to show the way the “puszta” did and did not exist. I also investigate the key factors that affected a new landscape shift, which brought about the colonial landscape.
Authors:Katalin Priskin, Gyöngyvér Tömöry, Erika Bogácsi-Szabó, Bernadett Csányi, and I. Raskó
, the wild aurochs is believed to be the ancestor of European domestic cattle,
. The geography and climate of the Great Hungarian Plain were well suited for these large grazing animals in the Late Neolithic. Till now, there are just a few aurochs mtDNA fragments available from two geographically restricted area, the British Isles and Italy. To increase our knowledge about the genetics of the European aurochsen livestock, and to investigate the phylogenetic position of a late Neolithic aurochs, excavated from the Carpathian Basin, mitochondrial DNA was extracted from a fragment of corpus mandibulae using ancient-DNA techniques and a portion of mitochondrial hypervariable region was amplified by PCR. The resulting sequence was aligned with GenBank sequences of 11 aurochsen. Our new sequence is identical with the sequence of two British aurochs. The 6000-year-old Hungarian aurochs shows a mtDNA sequence pattern, that occurs only among 6–12,000-year-old North European aurochsen, and it does not occur among modern, domesticated cattle.
Authors:A. Csecserits, R. Szabó, M. Halassy, and T. Rédei
We studied the vegetation of 54 sandy old-fields abandoned at different times. We first surveyed the vegetation in 1998 and developed predictions about the spontaneous succession using the chronosequence approach. Afterwards, we repeated the survey in 2000, 2001, 2002 and 2003, and based on this monitoring we tested the predictions of the chronosequence study. For both approaches, we analysed the changes in functional group composition during succession. According to the chronosequence study, the most important changes occurred in the youngest old-fields, abandoned 1–4 years ago: the species number and abundance of annuals, disturbance-requiring and anthropogenic species decreased, and those of perennials, grassland generalists, and species with low disturbance-tolerance increased. No changes were predicted for the older fields. The monitoring confirmed the predictions for the youngest old-fields. However, during the 5 years of monitoring several functional groups changed in their species number or abundance even on the older abandoned fields. Both of the methods showed that secondary succession on sandy old-fields is relatively fast. The chronosequence study provided a more static view of the processes, while the multi-year monitoring revealed that there were considerable inter-annual changes as well. With the yearly monitoring we can detect the effect of additional factors, such as land use changes (e.g., changes in grazing intensity) and yearly climate fluctuations on the direction and rate of secondary succession.
Competing species often coexist, but the mechanisms allowing long-term coexistence are rarely tested via direct experimental manipulation. We experimentally tested the mechanisms of coexistence in a classic model system, laboratory microcosms in which two species of ciliate protists competed for bacteria. Previous work shows that the species used here compete for bacteria, but can coexist despite large differences in grazing ability. We tested three hypotheses that might explain this surprising coexistence: resource partitioning, chemically-mediated interference competition, and differential use of space. To test for resource partitioning, we conducted an experiment testing the effects of bacterial species richness and composition on the long-term outcome of competition. Manipulating bacterial diversity and composition alters the scope for resource partitioning. Despite strong evidence for differential resource use (e.g., the two ciliates shifted bacterial species composition in different ways), initial bacterial richness and composition did not affect the long-term outcome of competition. Remarkably, the competitive outcome was unchanged even when ciliates competed for a single bacterial species, indicating that the observed resource partitioning is irrelevant to the competitive outcome. In further experiments, we ruled out differential space use and chemically-mediated interference competition as explanations for this surprising coexistence. Coexistence of ciliates on a single bacterial species might reflect partitioning of intraspecific bacterial diversity, and/or osmotrophy or consumption of particulate detritus by the weaker competitor. The results show that this classic model system is not as well-understood as had been previously thought. More broadly, the results dramatically illustrate that merely observing “niche differences” between coexisting species is no evidence that those differences are either necessary or sufficient for long-term coexistence.
Authors:E. Chaideftou, A. Kallimanis, E. Bergmeier, and P. Dimopoulos
Over millions of years there is a long-term increase in species richness, accompanied by substantial turnover in species composition. However, little is known about species temporal turnover over shorter, ecologically relevant time periods, such as years. In the present study, we examine the inter-annual temporal turnover in species composition in 100 m2 plots of the herbaceous layer in a submediterranean oak woodland over six years. We found that approximately half of the accumulated number of species over the six years is accommodated as temporal turnover. We also found that species temporal turnover in undisturbed control plots was not significantly different from that in plots where vegetation was recovering naturally without assistance, i.e., plots undergoing ecological succession. Only in the most disturbed (continuously overgrazed) plots temporal turnover was low to non-existent. We therefore suggest that diversity estimates based on a single year of observations may seriously underestimate species richness or the detrimental effects of disturbance, at least at the 100 m2 scale. Furthermore, we found that, with the exception of the heavily grazed plots, short-lived species (annuals and biennials) did not display significantly greater temporal turnover than long-lived (perennial) species. Our analysis also supports that the space for time substitution applies in the patterns of species turnover. Spatial species turnover was comparable to temporal turnover. Species that are observed in many plots are also present in many years, and vice versa. Also, the similarity in species composition decreased as the time period between observations increased, as is the case with distance decay. Overall we conclude that the patterns of species turnover in time resemble those in space, and thus temporal turnover makes an important contribution to total biodiversity that should not be ignored.