Preservation Of Taxa Research Articles

In situ conservation of Helosciadium nodiflorum: a crop wild relative of celery in Germany

Crop wild relatives (CWR) represent valuable sources of traits that can enhance the abiotic and biotic stress tolerance of crops. Due to climate change and expansion of land use, they may suffer from population decline, which increases the risk of losing these resources. The in situ conservation of CWR is receiving growing attention to preserve their intraspecific diversity. In contrast to the safeguarding of seeds ex situ, the preservation of taxa in their natural habitat facilitates the development of new adaptations to changing environmental conditions. However, studies aiming at the establishment of their in situ conservation are rare. Therefore, we identified and genotyped Helosciadium nodiflorum occurrences in Germany. Helosciadium nodiflorum is an endangered CWR of cultivated celery (Apium graveolens). For 20 occurrences the number of individuals, the number of sexually reproducing individuals, and potential threats were recorded. Genetic differences were examined using 17 newly developed simple sequence repeats (SSR). Population genetic analyses, like the inference of the compositional genetic differentiation, of population structure, and a Discriminant Analysis of Principal Components were conducted. The analyses revealed that most occurrences were genetically distinct. Geographically closely located populations are often also genetically more similar. Several populations revealed a composite genome indicative of hybridizations between distinct populations. Populations that experienced fixation were also identified. Based on the genetic diversity, the location in different ecogeographic units, and the support of local stakeholders, we recommend the establishment of 15 genetic reserves for H. nodiflorum in Germany.

Can soda ash dumping grounds provide replacement habitats for digger wasps (Hymenoptera, Apoidea, Spheciformes)?

BackgroundPublished sources document a loss of biodiversity at an extreme rate, mainly because natural and semi-natural ecosystems are becoming fragmented and isolated, thus losing their biological functions. These changes significantly influence biological diversity, which is a complex phenomenon that changes over time. Contemporary ecologists must therefore draw attention to anthropogenic replacement habitats and increase their conservation status. In our studies we show the positive role of soda ash dumping grounds as an alternative habitat for digger wasps, especially the thermophilic species.Methodology/Principal findingsIn the years 2007–2010 we carried out investigations in postindustrial soda ash dumping grounds located in Central Poland. We demonstrated that these areas serve as replacement habitats for thermophilic species of Spheciformes and, indirectly, for their potential prey. The studies were conducted in three microhabitat types, varying in soil moisture, salinity and alkalinity, that were changing in the course of ecological succession. We trapped 2571 specimens belonging to 64 species of digger wasps. Species typical of open sunny spaces comprised 73% of the whole inventory. The obtained results suggest that the stage of succession determines the richness, abundance and diversity of Spheciformes. The most favorable conditions for digger wasps were observed in habitats at late successional stages.Conclusions/SignificanceOur results clearly showed that these habitats were replacement habitats for thermophilous Spheciformes, including rare taxa that require genetic, species and ecosystem protection, according to the Biodiversity Convention. We showed that some types of industry might play a positive role in the preservation of taxa in the landscape, and that even degraded industrial wasteland can replace habitats under anthropopressure, serving as refugia of biological diversity, especially for disturbance-dependent species.

Pollen analysis of modern tree bark samples from the Manendragarh Forest Range of the Koriya district, Chhattisgarh, India

Pollen from modern tree bark samples collected in the Manendragarh Forest Range, Koriya District, Chhattisgarh, India, was investigated with the objective to understand the pollen rain in and around the study area, using modern tree bark samples as a new tool. The palyno-assemblages revealed the dominance of non-arboreals (herbs) over arboreals (trees and shrubs). Trees constitute an average of 17.23% pollen in the total pollen rain, whereas the average contribution of shrubs is only 0.33%. The non-arboreals have an average of 82.44% pollen in the total pollen rain. This bias in the form of representation of trees and shrubs, despite their ample presence in the forest, could be due to the differences in pollen production, dispersal and preservation of taxa, which depends on plant species and climatic conditions.

Diagenesis of bivalves from Jurassic and Lower Cretaceous lacustrine deposits of northeastern China

AbstractIn contrast to the numerous excellently preserved arthropods, vertebrates and plants from the Mesozoic lacustrine fossil lagerstätten of northeastern China, which have calcium phosphate or organic skeletons, the preservation of taxa with a calcareous skeleton is fairly poor. Here we investigate, using a scanning electron microscope and energy dispersive X-ray spectrometer, the preservational modes of bivalves from the Jurassic Daohugou Fossil Beds of Inner Mongolia and the Lower Cretaceous Yixian Formation of eastern Liaoning. The Jurassic bivalve Ferganoconcha sibirica is preserved as strongly compressed composite moulds which contain remains of the organic periostracum. In the Yixian Formation, the bivalves Sphaerium anderssoni and Arguniella ventricosa occur as compacted internal, external or composite moulds or are preserved with a silicified shell, and rarely with a shell consisting of iron hydroxides, which had replaced pyrite during late diagenesis/weathering. Silicification produced partly fabric-replacive microcrystalline quartz and partly void-filling megaquartz crystals after the carbonate shell had been dissolved. Films of authigenic aluminosilicate minerals, partly secondarily silicified, cover the exterior and interior shell surfaces. Occasionally, early diagenetic pyrite crystals, now oxidized to iron hydroxides, filled shell cavities forming internal moulds and rarely replaced the bivalve shell. The poor preservation of the bivalves reflects the environment and water chemistry of these lakes, which were heavily influenced by volcanic processes. Frequent ash deposition and decomposition of volcanic glass particles created acidic and alkaline lake and interstitial waters, which led to early diagenetic formation of authigenic aluminosilicate minerals, ferruginous internal moulds, dissolution of shell carbonate and silicification of shells.