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1.
Zootaxa ; 4903(2): zootaxa.4903.2.5, 2021 Jan 07.
Article in English | MEDLINE | ID: mdl-33757098

ABSTRACT

The species Minoa murinata (Scopoli, 1763) sensu lato is examined throughout its distribution range. Specimens from central Europe (Germany, Italy, France) are compared with those from Serbia, Croatia, Slovenia and newly collected specimens from eastern Turkey, Armenia, Georgia and Russia. The study is based on a combination of behavioural observations, morphological characters (size, wing coloration, structure of male and female genitalia) as well as genetic data (DNA barcoding). The taxon Minoa murinata var. monochroaria Herrich-Schäffer, 1848 is downgraded from subspecies rank to synonymy of M. murinata. Morphological study of the populations from eastern Turkey, Armenia, Georgia and Russia confirm the taxon Minoa murinata f./ssp. lutea Schwingenschuss, 1954 as a bona species. It is herewith upgraded from synonymy of M. murinata to species level. The results of DNA barcoding are discussed. Wing pattern, male and female genitalia of both species are illustrated.


Subject(s)
Lepidoptera , Moths , Animals , Female , Male , Moths/genetics
2.
Sci Total Environ ; 699: 134302, 2020 Jan 10.
Article in English | MEDLINE | ID: mdl-31522046

ABSTRACT

Quantifying the catchment water balance and the characterization of its water quality changes are effective tools for establishing the response of catchments to shifting land management practices. Here we assess long-term hydrological partitioning and stream water chemistry over a 30-year period in a rural mixed land use catchment in northern Germany undergoing riparian wetlands and widespread re-colonization by beavers (Castor fiber) along the river network. We used long-term spatially distributed stream discharge, groundwater levels and surface water quality data with a simple monthly water balance model, changes in the variability in discharge measurements, and statistical analysis of spatio-temporal changes in stream water quality to assess long-term changes. Water balance estimates indicated high proportions of evapotranspiration loss (~90% of total precipitation) and relatively low groundwater recharge (<5% of total precipitation) prior to riparian rehabilitation in 2000. Increasing groundwater levels from 2000 to 2017 and the relatively linear nature of the catchment storage - discharge relationship, indicate a gradual increase in groundwater recharge (buts still <10% of total precipitation). Wetland rehabilitation, greatly enhanced by increasing beaver populations, resulted in longer water transit times in the stream network, less linear storage-discharge relationship and a loss of daily stream variability, increased DOC concentrations, isotopic evaporative enrichment downstream, and moderated stream temperatures. There was limited long-term water quality improvements from wetland rehabilitation on either nitrate or total phosphorus concentrations, with unchanged seasonal summer and winter peak concentrations for phosphorus and nitrate, respectively. This likely reflects the long-term legacy of fertilizer use on nutrient reservoirs in the catchment's soils, aquifers, and stream network. These long-term changes in hydrology and stream chemistry resulting from riparian rehabilitation and changes in agricultural management practices provide invaluable insights into catchment functioning and an evidence base for future planning in relation to long-term climatic changes.


Subject(s)
Environmental Monitoring , Rodentia , Wetlands , Agriculture , Animals , Environmental Restoration and Remediation , Germany , Groundwater , Hydrology , Nitrates , Nitrogen , Phosphorus , Rivers , Soil , Water , Water Movements , Water Quality
3.
Sci Rep ; 5: 16328, 2015 Nov 06.
Article in English | MEDLINE | ID: mdl-26541809

ABSTRACT

Agricultural land covers approximately 40% of Earth's land surface and affects hydromorphological, biogeochemical and ecological characteristics of fluvial networks. In the northern temperate region, agriculture also strongly affects the amount and molecular composition of dissolved organic matter (DOM), which constitutes the main vector of carbon transport from soils to fluvial networks and to the sea, and is involved in a large variety of biogeochemical processes. Here, we provide first evidence about the wider occurrence of agricultural impacts on the concentration and composition of fluvial DOM across climate zones of the northern and southern hemispheres. Both extensive and intensive farming altered fluvial DOM towards a more microbial and less plant-derived composition. Moreover, intensive farming significantly increased dissolved organic nitrogen (DON) concentrations. The DOM composition change and DON concentration increase differed among climate zones and could be related to the intensity of current and historical nitrogen fertilizer use. As a result of agriculture intensification, increased DON concentrations and a more microbial-like DOM composition likely will enhance the reactivity of catchment DOM emissions, thereby fuelling the biogeochemical processing in fluvial networks, and resulting in higher ecosystem productivity and CO2 outgassing.

4.
Antonie Van Leeuwenhoek ; 108(6): 1457-1468, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26437638

ABSTRACT

In the context of studying the influence of N-fertilization on N2 and N2O flux rates in relation to the soil bacterial community composition in fen peat grassland, a group of bacterial strains was isolated that performed dissimilatory nitrate reduction to ammonium and concomitantly produced N2O. The amount of nitrous oxide produced was influenced by the C/N ratio of the medium. The potential to generate nitrous oxide was increased by higher availability of nitrate-N. Phylogenetic analysis based on the 16S rRNA and the rpoB gene sequences demonstrated that the investigated isolates belong to the genus Proteus, showing high similarity with the respective type strains of Proteus vulgaris and Proteus penneri. DNA-DNA hybridization studies revealed differences at the species level. These differences were substantiated by MALDI-TOF MS analysis and several distinct physiological characteristics. On the basis of these results, it was concluded that the soil isolates represent a novel species for which the name Proteus terrae sp. nov. (type strain N5/687(T) =DSM 29910(T) =LMG 28659(T)) is proposed.


Subject(s)
Ammonia/metabolism , Nitrates/metabolism , Nitrous Oxide/metabolism , Proteus/classification , Proteus/isolation & purification , Soil Microbiology , Bacterial Typing Techniques , Carbon/metabolism , Cluster Analysis , Culture Media/chemistry , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA-Directed RNA Polymerases/genetics , Deinococcus , Molecular Sequence Data , Nitrogen/metabolism , Nucleic Acid Hybridization , Phylogeny , Proteus/genetics , Proteus/metabolism , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
5.
Environ Manage ; 51(6): 1194-209, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23636204

ABSTRACT

The restoration of ecosystem services, i.e., production, regulation, and information, is a global challenge, which the federal state of Mecklenburg-Vorpommern in NE Germany addressed in 2000 by rewetting over 20,000 ha of degraded peatlands within the Mire Restoration Program. We evaluated ecosystem services in 23 rewetted sites by assessing the following mire parameters within a ten year period: (a) dominant vegetation at the ecosystem level, (b) peat formation potential at the landscape level, and (c) aboveground biomass and nutrient levels. Seven to 10 years after rewetting, the wetlands formed a mosaic of vegetation types with the highest potential for peat formation and several dominant, peat-forming species accumulated high levels of aboveground biomass and nutrients (C, N, P). Common reed (Phragmites australis) accumulated the most biomass (up to 24 t dry matter/ha), and N+P during the growing season. A future management option is to annually harvest aquatic and wetland plants to reduce nutrient levels in restored mire ecosystems.


Subject(s)
Ecosystem , Wetlands , Carbon/analysis , Conservation of Natural Resources , Germany , Magnoliopsida/growth & development , Nitrogen/analysis , Phosphorus/analysis , Soil
6.
Sci Total Environ ; 438: 435-46, 2012 Nov 01.
Article in English | MEDLINE | ID: mdl-23026150

ABSTRACT

Dissolved organic matter (DOM) is an important part of the global carbon cycle and significantly influences aquatic ecosystem functions. Recent studies suggest that its amount and composition in freshwaters may be altered by agricultural land use, whereby the influence of preceding in-stream production and processing is not clear. To assess the land use effect on DOM amount and composition for the export from terrestrial to freshwater systems at the land-water interface, we sampled headwater streams draining agricultural and near-pristine catchments (forested and wetland) in the North German plains. To account for spatial and seasonal variation, we conducted a screening of DOM amount (53 sites) and composition (42 sites), and conducted bi-weekly samplings to investigate seasonal variation at eight sites over one year. Concentrations of dissolved organic carbon (DOC) were significantly higher for agricultural and wetland catchments than for forested catchments. Moreover, DOC loads exhibited higher seasonal variation for agricultural and wetland catchments than for forested catchments, which was due to higher variation in discharge. Parallel Factor Analysis revealed that the composition of DOM in agricultural catchments was significantly different from the other studied catchment types, and was characterized by low redox state and high structural complexity. Moreover, a gradient from protein- to humic-like fluorescence significantly separated forested from agricultural and wetland catchments. The contribution of humic-like DOM was strongly and positively related to DOC concentration, suggesting a mechanistic coupling of both. The effects of land use on patterns of DOC concentration and DOM composition were consistent across seasons, implying that land use strongly regulates DOM export. Overall, this study clearly shows the seasonally independent importance of agricultural land use for the amount and composition of DOM fluxes from the terrestrial zone to surface waters. These altered fluxes may affect ecosystem metabolism and health of agricultural headwaters and downstream situated aquatic ecosystems.


Subject(s)
Agriculture/methods , Humic Substances/analysis , Organic Chemicals/analysis , Rivers/chemistry , Analysis of Variance , Carbon/metabolism , Factor Analysis, Statistical , Germany , Oxidation-Reduction , Seasons , Spectrometry, Fluorescence
7.
Ecol Appl ; 20(5): 1336-49, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20666253

ABSTRACT

Rewetting of drained fens is necessary to stop further soil degradation and to reestablish important ecological functions. However, substantial changes of peat characteristics in the upper soil layers, due to drainage and land use, could counteract their recovery as nutrient-poor systems for an unknown period. We assessed the importance of altered peat properties, such as the degree of peat decomposition and the amount of redox-sensitive phosphorus (P) compounds, for P mobilization in different degraded fens. An experimental design involving 63 intact peat cores from fens with varying drainage and land-use histories was developed to quantify the mobilization of P, as well as that of iron (Fe), ammonium, carbon dioxide, and methane, all indicators of organic-matter decomposition and/or P-releasing processes. We found that net P release rates in peat cores with highly decomposed peat (range: 0.1-52.3 mg P x m(-2) x d(-1)) were significantly correlated to the amount of P bound to redox-sensitive compounds and the molar Fe:P as well as Al:P ratios of peat. We conclude that the following general rules apply for P mobilization in rewetted fens: (1) elevated levels of P release rates and P concentrations in pore water up to three orders of magnitude larger than under natural reference conditions can only be expected for rewetted fens whose surface soil layers consist of highly decomposed peat; (2) peat characteristics, such as the amount of P bound to redox-sensitive Fe(III) compounds (positive correlation) and molar ratios of Fe:P or Al:P (negative correlations), explain the high range of P release rates; and (3) a critical P export to adjacent lakes or rivers can only be expected if molar Fe:P ratios of highly decomposed peat are less than 10.


Subject(s)
Soil , Wetlands , Ammonia/chemistry , Carbon Dioxide/chemistry , Iron/chemistry , Methane/chemistry , Phosphorus/chemistry
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