Schwermetalle und organische Umweltchemikalien in Rehwild (Capreolus capreolus L.) aus Forst- und Agrarstandorten

The roe deer indicates the contamination of ecosystems with environmental chemicals. The influence of land use on the contamination of five different forest and agricultural ecosystems in Rheinland Pfalz was proven. The cadmium and lead content was measured in renal tissue of the roe deer. The organic chemicals PCB, α-HCH, Lindan, DDT, and DDE were investigated in kidneys and liver and correlated to adipose tissue. The following results have been obtained: Lead: The Pb-contamination was generally low in all ecosystems investigated. Cadmium: The Cd-values showed an area-dependend contamination of the organs. The data of the test organs from the forest sites and the semi-agricultural area were 2–4 times higher than the ZEBS-limit. The contamination of the animals corresponded to the wet deposition of Cd in the regions. σPCB: The PCB-results indicated a relativly high contamination of the ecosystems. The PCB-ZEBS-limit for the interior organs was surpassed in all areas.α-HCH, γ-HCH (Lindan): The uniformly low values of the HCH-group indicated that these compounds were probably not of ecotoxicological significance in the agricultural and forest regions.DDT, DDE: The results obtained showed a low background contamination in all ecosystems investigated. Areas with former high DDT-applications revealed higher values of DDE in the tissues. ZEBS: Central institution for the evaluation of chemicals in the environment (Bundesgesundheitsamt)     

Abschätzung des umweltchemischen und ökotoxikologischen Verhaltens von Stoffen durch computergestützte Analyse von Struktur und Verhalten sowie von Struktur und Wirkung

Risk assessment of chemicals requires comprehensive data material, which often is not available. To provide substitutes for the lacking experimental ecotoxicological and physico-chemical data, a software-system (SAR-System) has been developed comprising more than 90 estimation models for relevant endpoints. The approach is based on quantitative structure-activity relationships (QSAR). Two major aspects characterize the SAR-System:

1. The implemented models were tested for their validity and application range.
2. The QSARs are accessible by a menu-driven programme package.

The following endpoints are included: Thysico-Chemical Data: 1-Octanol/water-partition-coefficient log P_ow, vapour pressure, water solubility, pK_a-value, boiling point Biological Data: Toxicity towards fish, daphnia, tetrahymenae, algae, bacteria and mammals, mutagenicity. Distribution: soil sorption, bioconcentration, Henry-Constant, Mackay (Level I). Degradation: photodegradation, biodegradability.     

Teil I: Das Osnabrücker Umweltmanagement-Modell für Hochschulen

Through their use of energy and materials, universities cause a great deal of environmental pollution which could be reduced considerably by an effective choice of organizational and technical measures. There are some examples for environmental protection measures at several universities, but a professional environmental management system (EMS) for universities with a systematic approach to reduce the consumption of resources is lacking. At the University of Osnabrück, the basis for an EMS applicable for a university has been developed for the first time in Germany and the use of this system can also be transferred to other universities. The EMS is composed of ten building blocks, for example, alteration of the administration’s organizational structure, adoption of environmental guidelines, analysis of the energy and material flows which result in an eco-balance, an environmental program or measures to inform the staff and to help to involve them in environmental management. Over the next months, these ten building blocks will gradually be implemented at the University of Osnabrück. Five articles will provide an overview about the EMS developed for the University of Osnabrück as a whole and will describe parts of the material and energy flow analysis, and the planned environmental information system.

Part I: An Environmental Management Model for Universities: From Environmental Guidelines to the Involvement of Employees

Part II: The Energy Balance of the University of Osnabrück: Analysis of the Energy Flows and Conclusions

Part III: The Traffic Balance of the University of Osnabrück: Calculation of the Environmental Pollution which is caused by the University’s Commuters and Business Trips

Part IV: A Concept of Waste Reduction for the University of Osnabrück: Constructing the Waste Balance and Measures to Inform and Involve the Staff

Part V: The Planned Environmental Information System of the University of Osnabrück: Concept and Integration into the Management Information System

     

Metabolism of neolignans from P. regnellii (Piperaceae) in the beetle Naupactus bipes (Coleoptera: Curculionidae)

Piper regnellii (Piperaceae) contains high levels neolignans with diverse biological activities, including insecticidal. Despite the insecticidal activity of these neolignans, Naupactus bipes (Coleoptera: Curculionidae) larvae and adults were found feeding on the leaves (adults) and roots (larvae) of P. regnellii. The present study investigated the metabolic pathway of neolignans from P. regnellii leaves in the beetle N. bipes, focusing on possible biotransformation or sequestration of these compounds by the beetle. Two of the four plant neolignans could be recovered in the feces of adults feeding on P. regnellii leaves. In addition, four degradation products were detected, including the neolignan 3-[(2R,3R)-2,3-dihydro-3-(methyl)-2-(4-hydroxyphenyl)-5-benzofuranyl]-(2E)-propenal (7), an oxidation product of conocarpan, the major plant neolignan. The adult beetle sequesters the neolignan conocarpan selectively from leaves as well as accumulates neolignan 7. Neolignan 7 was also detected in the larvae of lab-reared beetles.     

Effect of nitrogen source on short-term light and dark CO2 uptake by a marine diatom

Based on a series of short-term incubations involving the marine diatom Chaetoceros simplex (Bbsm), precultured in NH ₄ ⁺ -, NO ₃ ^- -and urea-limited continuous cultures at several dilution rates, we found that both the short-term specific rate of ¹⁴CO₂ uptake and the amount of CO₂ fixed after 8- and 16-min incubations were unaffected by enrichment with NH ₄ ⁺ , urea, or NO ₃ ^- when NH ₄ ⁺ or urea were the preconditioning forms of N, but were slightly suppressed when the cells were first grown on NO ₃ ^- . Similar enrichments in the dark, however, led to significant CO₂ uptake under all conditions of NH ₄ ⁺ enrichment and to similarly enhanced CO₂ uptake, but only at high growth rates, when urea was the source of enrichment nitrogen. Our light results are contrary to some contemporary findings, but there does seem to be agreement that photosynthetic rates of rapidly growing phytoplankton will not be affected by exposure to pulses of nitrogen. Enhanced dark uptake, in contrast, appears to be characteristic of phytoplankton under all degrees of N limitation, and, as such, may be useful as an “all or nothing” index of the nitrogen status of natural waters. There is some indication that the index may be useful in determining both the form of and the degree of N limitation as well.     

Distribution of phytoplankton community and its influence factors in an urban river network,East China

To reveal the distribution characteristics of phytoplankton and the main influence factors under different conditions in the urban rivers, the investigations were conducted during autumn and winter 2014 in Changzhou City, East China. 178 taxa of phytoplankton belonging to 28 functional assemblages were identified. In autumn, the phytoplankton community compositions have high similarity for enhanced hydrological connectivity. The chlorophytes and diatoms (prevailing functional groups C, F, J, P), together with euglenoids (W1), showed high proportions of biomass in the main rivers and connected rivers. It was related to the well mixed eutrophic conditions. The phytoplankton community exhibited spatiotemporal heterogeneity in winter. Affected by the low water level and temperature, the free-living phytoflagellates (X2) replaced groups F and J in the main rivers. Phytoplankton productivity was the highest in the Tongji River. Chlorophytes Dictyosphaerium ehrenbergianum and Chlamydobotrys stellata had an overwhelming superiority during the winter bloom. They were significantly correlated with ammonium, total phosphorus and biochemical oxygen demand. Affected by tail water supply, the diatoms (MP) and euglenoids (W1) dominated in a beheaded river. The multivariate analyses based on the phytoplankton functional groups helped to evaluate the relationships and variations between the urban rivers. The redundancy analysis (RDA) results showed that nitrate nitrogen, water temperature, total nitrogen and total suspended solids were the main influence factors on the phytoplankton community. Except MP, the prevailing groups all showed significant negative correlations with nitrate nitrogen. Availability and utilization of dissolved inorganic nitrogen and hydrodynamic conditions affected the phytoplankton distribution.

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Phytotoxic effects of phenolic acids from <Emphasis Type="Italic">Merostachys riedeliana,</Emphasis> a native and overabundant Brazilian bamboo

Merostachys riedeliana Rupr. is a native and overabundant bamboo species in the Brazilian Atlantic Forest. Moderate to strong allelopathic activity may be one mechanism that explains this super-dominance and the changes in structure and composition of forest areas occupied by bamboo. This study evaluated the phytotoxic effect of M. riedeliana extracts and fractions and identified their putative allelochemicals. We investigated the presence of allelochemicals in soil collected from stands occupied by M. riedeliana. Furthermore, we evaluated the putative effect of tree allelochemicals, individually and combined, on germination and growth. The aqueous extract of leaves and its ethyl acetate fraction presented the highest inhibitory effects on seed germination and seedling growth. The effect of the extracts and fractions on the target species was species-specific. Neither the individual nor the combined phenolic acids significantly inhibited seed germination; however, a pronounced growth inhibition was observed in M. bimucronata seedlings treated with vanillic acid and in E. verna and M. bimucronata seedlings treated with combined phenolic acids. Isovitexin, vitexin, isoorientin, orientin, and their O-glycoside derivatives, the lactonic dimer of the p-hydroxybenzoic acid and 3,4-methylenedioxymandelic acid were identified in the aqueous extracts and ethyl acetate fraction by Liquid Chromatography-Diode Array Dectector/Electrospray Ionization/Mass Spectrometry (LC-DAD/ESI–MS/MS). The Gas Chromatography-Mass Spectrometer (GC–MS) profile of the same extract and fraction showed the presence of benzoic, benzeneacetic, salicylic, p-hydroxybenzoic, p-hydroxyphenylacetic, vanillic, p-coumaric, protocatechuic, syringic, gallic, m-coumaric vanillylmandelic, 4-methylmandelic, 3,4-methylenedioxymandelic and trans-ferulic acids. The p-benzoic acid and the apigenin 6-C-glucoside (isovitexin) were identified in the soil extract collected from under bamboo-growing areas. Even though laboratory bioassays are not completely predictive of the allelopathic effects that occur in nature, the results of this study provide preliminary evidence of allelopathy as a possible species-specific inhibition mechanism of native species that explain the impoverishment of floristic richness and the functional groups in areas where M. riedeliana is overabundant.     

PEPC-Aktivität

The criteria currently used to determine the extent of novel forest decline areleaf loss andyellowing of leaves. However, these criteria have only a limited value for indicating damage of woody trees, especially the early stages. Therefore, physiological-biochemical parameters will be useful to measure the extent of forest decline. Results from several natural spruce stands indicate that in needles with early signs of damage and needles with severe damage PEPC activity is significantly higher than in needles of healthy plants. Therefore, PEPC activity can reveal beginning damage and may be used as abiochemical indicator for damage assessments of spruce. The influence of air pollutants on PEPC activity in spruce needles was measured in fumigation chambers and open-top chambers; PEPC activity was shown to be affected by long-term exposition only.     

Fitting a parabola to growth data of fishes and some applications to fisheries

Denoting a fish length or weight at age t by X _t , a reference age by t _m , and the corresponding fish length or weight by X _m , the relation between age and length or weight may be described by a parabola as follows: $$\left| {X_t } \right. - X_m \left| = \right.a + b(\left| {t - t_m } \right.\left| ) \right. + c(\left| t \right. - t_m \left| ) \right.^2$$ or $$X_t = A + b(\left| {t - t_m } \right.\left| ) \right. + c(\left| t \right. - t_m \left| ) \right.^2$$ where a, b and c are constants. Each of the above Eqs. describes one curve at ages older than t _m and another one at younger ages, which is made possible by means of the transformation of t to (|t-t _m |). In 2 cases out of 10, the parabola takes the form of a cubic equation. Evidence is given that, as the growth data become fewer, the better fit of the parabola or cubic equation will probably be less in comparison to the von Bertalanffy equation (1938, 1949) as developed by Beverton and Holt (1957) and the power-growth equation (Rafail, 1971), and vice versa. This growth equation is used to derive models for estimating the optimum age and yield for fish populations.     

Data depth for the uniform distribution

Given a set $X$ of $k$ points and a point $z$ in the $n$ -dimensional euclidean space, the Tukey depth of $z$ with respect to $X$ , is defined as $m/k$ , where $m$ is the minimum integer such that $z$ is not in the convex hull of some set of $k-m$ points of $X$ . If $z$ belongs to the closed region $B$ delimited by an ellipsoid, define the continuous depth of $z$ with respect to $B$ as the quotient $V(z)/\text{ Vol }(B)$ , where $V(z)$ is the minimum volume of the intersection of $B$ with the halfspaces defined by any hyperplane passing through $z$ , and $\text{ Vol }(B)$ is the volume of $B$ . We consider $z$ a random variable and prove that, if $z$ is uniformly distributed in $B$ , the continuous depth of $z$ with respect to $B$ has expected value $1/2^{n+1}$ . This result implies that if $z$ and $X$ are uniformly distributed in $B$ , the expected value of Tukey depth of $z$ with respect to $X$ converges to $1/2^{n+1}$ as the number of points $k$ goes to infinity. These findings have applications in ecology, namely within the niche theory, where it is useful to explore and characterize the distribution of points inside species niche.     

Etude expérimentale de la ponte chez trois espèces de copépodes pélagiques (Centropages typicus,Acartia clausi et Temora stylifera)

Egg-laying of 3 common copepod species from the Gulf of Marseilles (Centropages typicus Kröyer, Acatia clausi Giesbrecht, Temora stylifera Dana) has been studied under various trophic conditions, at different periods of the year. The role of phytoplankton abundance in the induction and importance of egg-laying is indicated. The specific quality of the algal suspension used for feeding affected also fertility. A seasonal variation in the importance of egg-laying is established. Some observations are made on egg deposition and development.     

Enhanced biohydrogen generation from organic wastewater containing NH 4 + by phototrophic bacteria Rhodobacter sphaeroides AR-3

NH ₄ ⁺ is typically an inhibitor to hydrogen production from organic wastewater by photo-bacteria. In this experiment, biohydrogen generation with wild-type anoxygenic phototrophic bacterium Rhodobacter sphaeroideswas found to be sensitive to NH ₄ ⁺ due to the significant inhibition of NH ₄ ⁺ to its nitrogenase. In order to avoid the inhibition of NH ₄ ⁺ to biohydrogen generation by R. sphaeroides, a glutamine auxotrophic mutant R. sphaeroides AR-3 was obtained by mutagenizing with ethyl methane sulfonate. The AR-3 mutant could generate biohydrogen efficiently in the hydrogen production medium with a higher NH ₄ ⁺ concentration, because the inhibition of NH ₄ ⁺ to nitrogenase of AR-3 was released. Under suitable conditions, AR-3 effectively produced biohydrogen from tofu wastewater, which normally contains 50–60 mg/L NH ₄ ⁺ , with an average generation rate of 14.2 mL/L·h. This generation rate was increased by more than 100% compared with that from wild-type R. sphaeroides.     

Passive scalar roughness lengths for atmospheric boundary layer flow over complex, fractal topographies

When modeling atmospheric boundary layer flow over rough landscapes, surface fluxes of flow quantities (momentum, temperature, etc.) can be described with equilibrium logarithmic law expressions, all of which require specification of a roughness length that is, physically, the elevation at which the flow quantity equals its surface value. In high Reynolds number flows, such as the atmospheric boundary layer, inertial forces associated with turbulent eddy motions are responsible for surface momentum fluxes (form, or pressure drag). Surface scalar fluxes, on the other hand, occur exclusively via diffusion in the immediate vicinity of the topography—the interfacial region—before being advected by turbulent eddy motions into the bulk of the flow. Owing to this difference in surface transfer mechanism, the passive scalar roughness length, $z_{0S}$ , is known to be less than the momentum roughness length, $z_0$ . In this work, classical relations are used to specify $z_{0S}$ during large-eddy simulation of atmospheric boundary layer flow over aerodynamically rough, synthetic, fractal topographies which exhibit power-law height energy spectrum, $E_h (k) \sim k^{\beta _s}$ , where $\beta _s$ is a (predefined) spectral exponent. These topographies are convenient since they resemble natural landscapes and $\beta _s$ can be varied to change the topography’s aerodynamic roughness (the study considers a suite of topographies with $-2.4 \le \beta _s \le -1.2$ , where $-2.4$ and $-1.2$ are the “most smooth” and “most rough” cases, respectively, corresponding with roughness Reynolds number, $Re_0 \approx 10$ and $300$ ). It is often assumed that $z_{0S}/z_{0} \approx 10^{-1}$ for all $Re_0$ . But results from this work show that the roughness length ratio, $z_{0S}/z_{0}$ , depends strongly on $Re_0$ , ranging between $10^{-3}$ and $10^{-1}$ .     

Gravity currents with double stratification: a numerical and analytical investigation

We consider high-Reynolds-number Boussinesq gravity current and intrusion systems in which both the ambient and the propagating “current” are linearly stratified. The main focus is on a current of fixed volume released from a rectangular lock; the height ratio of the fluids $H$ , the stratification parameter of the ambient $S$ , and the internal stratification parameter of the current, $\sigma $ , are quite general. We perform two-dimensional Navier–Stokes simulation and compare the results with those of a previously-published one-layer shallow-water model. The results provide insights into the behavior of the system and enhance the confidence in the approximate model while also revealing its limitations. The qualitative predictions of the model are confirmed, in particular: (1) there is an initial “slumping” stage of propagation with constant speed $u_N$ , after which $u_N$ decays with time; (2) for fixed $H$ and $S$ , the increase of $\sigma $ causes a slower propagation of the current; (3) for some combinations of the parameters $H,S, \sigma $ the fluid released from the lock lacks initially (or runs out quickly of) buoyancy “driving power” in the horizontal direction, and does not propagate like a gravity current. There is also a fair quantitative agreement between the predictions of the model and the simulations concerning the spread of the current.     

Biologische Tests von Bodenextrakten zur Erkennung von Bodenkontaminationen Einstiegswerte und Test-Fensterbreite

Initial values and windows of competence together with a biological test system are introduced to identify soil contaminations. Theinitial values are defined as the amount of extract equivalent to a defined amount of soil (gramm soil equivalent) and the same amount of test medium. This is equivalent to a complete replacement of the test medium with the soil being tested. Theeffect limits should be at least the double standard deviation of the blank values. Based on the values found when testing uncontaminated soils, a higher threshold value has to be established for some test systems. Should no relationship be found to a standard test medium (e.g. agar as a matrix in the Ames assay), the so-calledwindow of competence is defined. Within this window no natural response is found when ex amining uncontaminated soil. For mutagenicity tests, the double spontaneous reversion rate (reversion coefficient of 2) as related o the blank sample is evaluated as the effect limit.     

Marine fungi deteriorating chitin of hydrozoa and keratin-like annelid tubes

Higher marine fungi were found for the first time as degraders of chitinous exoskeletons of hydrozoa and of keratinous (?) tubes of annelids. Collections were made in several locations of the Atlantic and Pacific Oceans. Fruiting bodies and hyphae of the ascomycete Abyssomyces hydrozoicus Kohlm. occurred on hydrozoa at a depth of 631 to 641 m near the South Orkney Islands. Sterile mycelia, some of them resembling Dictyonema zoophytarum Reinsch, were collected on hydrozoa on the North Carolina coast, and offshore at a depth of 46 to 73 m. Tubes of the polychaete Chaetopterus variopedatus (Renier) washed ashore in California contained ascocarps and mycelia of Lulworthia sp. Hyphal growth on and in the animal tubes is described and illustrated.     

Die Wirkung von Photooxidantien auf Sommerweizen (Triticum aestivum L. Star)

The effect of short-time fumigation with the peroxidic photooxidants ozone, peroxyacetyl nitrate (PAN), and hydrogen peroxide (H₂O₂) on the gas exchange of wheat leaves was investigated. Two types of experiments are to be distinguished:

1. Fumigation is carried out at atmospheric CO₂ partial pressure (350 μbar) and the assimilation and transpiration rates are followed simultaneously.
2. The alteration of CO₂-response curves by fumigation is determined; from this, characteristic photosynthetic parameters can be calculated.

With this method, statements about the reaction of both photosynthesis as a whole and specific reaction sites within the most important photosynthetic processes are possible. Ozone in concentrations of 260–280 ppb causes a primary perturbation of the photosynthetic apparatus, whereby the carboxylation rate is affected to nearly the same extent as the electron-transport rate.PAN (120 ppb) causes a reduction in the assimilation rate, primarily due to the closing of the stomata. H₂O₂ affects the gas exchange only in concentrations of above 1 ppm, whereby the reduction of the assimilation rate represents an almost pure stomatal effect. All three fumigants cause an increase in the respiration rate, which may point to an activation of detoxification and repair mechanisms.