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1.
Kengara Fredrick Orori Doerfler Ulrike Welzl Gerhard Munch Jean Charles Schroll Reiner 《Environmental science and pollution research international》2019,26(9):8779-8788
Environmental Science and Pollution Research - DDT transformation to DDD in soil is the most commonly reported pathway under anaerobic conditions. A few instances of DDT conversion to products... 相似文献
2.
Degradation, bioaccumulation and volatile loss of the 14C-labeled phenylurea herbicide isoproturon (IPU) was examined in a freshwater microcosm with the free floating macrophyte species Lemna minor during a 21-day exposure time. Isoproturon volatilisation was very low with 0.13+/-0.01% of the initially applied herbicide. Only a minor amount of the herbicide was completely metabolised, presumably by rhizosphere microorganisms and released as 14CO2. In total, about 9% isoproturon was removed from the aquatic medium during 21 days. The major portion of the pesticide was removed by bioaccumulation of Lemna minor (5.0+/-0.8%) and the bioconcentration factor (BCF) based on freshweight was 15.8+/-0.2. However, this study indicated a high persistence of IPU in freshwater ecosystems and a potential hazard due to bioaccumulation in non-target species. The novel experimental system of this study, developed for easy use and multiple sampling abilities, enabled quantitatively studying the fate of isoproturon and showed high reproducibility with a mean average (14)C-recovery rate of 97.1+/-0.7%. 相似文献
3.
Grundmann S Fuss R Schmid M Laschinger M Ruth B Schulin R Munch JC Schroll R 《Chemosphere》2007,68(3):511-517
Through transfer of an active, isoproturon degrading microbial community, pesticide mineralization could be successfully enhanced in various soils under laboratory and outdoor conditions. The microbes, extracted from a soil having high native ability to mineralize this chemical, were established on expanded clay particles and distributed to various soils in the form of microbial "hot spots". Both, diffusion controlled isoproturon mass flow towards these "hot spots" (6microg d(-1)) as well as microbial ability to mineralize the herbicide (approximately 5microg d(-1)) were identified as the main processes enabling a multiple augmentation of the native isoproturon mineralization even in soils with heavy metal contamination. Soil pH-value appears to exert an important effect on the sustainability of this process. 相似文献
4.
Isolation and characterization of 1,2,4-trichlorobenzene mineralizing Bordetella sp. and its bioremediation potential in soil 总被引:1,自引:0,他引:1
Wang F Grundmann S Schmid M Dörfler U Roherer S Charles Munch J Hartmann A Jiang X Schroll R 《Chemosphere》2007,67(5):896-902
A soil which has been polluted with chlorinated benzenes for more than 25 years was used for isolation of adapted microorganisms able to mineralize 1,2,4-trichlorobenzene (1,2,4-TCB). A microbial community was enriched from this soil and acclimated in liquid culture under aerobic conditions using 1,2,4-TCB as a sole available carbon source. From this community, two strains were isolated and identified by comparative sequence analysis of their 16S-rRNA coding genes as members of the genus Bordetella with Bordetella sp. QJ2-5 as the highest homological strain and with Bordetella petrii as the closest related described species. The 16S-rDNA of the two isolated strains showed a similarity of 100%. These strains were able to mineralize 1,2,4-TCB within two weeks to approximately 50% in liquid culture experiments. One of these strains was reinoculated to an agricultural soil with low native 1,2,4-TCB degradation capacity to investigate its bioremediation potential. The reinoculated strain kept its biodegradation capability: (14)C-labeled 1,2,4-TCB applied to this inoculated soil was mineralized to about 40% within one month of incubation. This indicates a possible application of the isolated Bordetella sp. for bioremediation of 1,2,4-TCB contaminated sites. 相似文献
5.
Reiner Schroll Sabine Grundmann Ulrike Dörfler Bernhard Ruth Jean Charles Munch 《Water, Air, & Soil Pollution: Focus》2008,8(2):209-216
Several lysimeter scenarios and approaches exist to study the fate of agro-chemicals or contaminants from deposition in soil
columns. In many systems just transport and leaching of the parent compound is followed, in some systems the leaching and
transport of the metabolites is investigated as well. In more sophisticated lysimeter systems the volatilization and also
the mineralization of the applied chemicals can be additionally monitored. Depending on the lysimeter system used and on the
fact whether the applied chemicals are 14C-labeled or not, different results and various interpretations of the results might be achieved. Different lysimeter systems
are described in this paper and a real dataset of a specific lysimeter experiment was transferred and evaluated in a virtual
approach in the different lysimeter systems in order to show the advantages and disadvantages of the various systems. 相似文献
6.
T. Wagner L. M. Arango Isaza S. Grundmann U. Dörfler R. Schroll M. Schloter A. Hartmann H. Sandermann D. Ernst 《Water, Air, & Soil Pollution: Focus》2008,8(2):155-162
The gene transfer from glyphosate tolerant soybean to Bradyrhizobium japonicum was evaluated in a free-air lysimeter experiment under natural conditions and increasing selection pressure, to monitor for the probability of horizontal gene transfer (HGT). A large volume lysimeter study that offers conditions comparable to normal farming was conducted in 2004 and 2005 with Roundup Ready® (RR) soybean and Roundup® application according to agricultural practice. Analysis of nodules showed, as expected, the presence of the transgenic 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). However, in bacteroids that were isolated from nodules and then cultivated for several rounds in the presence of high levels of glyphosate, the EPSPS gene could no longer be detected. This indicates no stable HGT transfer of the whole EPSPS gene under field conditions. 相似文献
7.
A study to compare the extent of atrazine mineralization in soils from Kenyan sugarcane-cultivated fields with and without history of atrazine use was carried out in the laboratory under controlled conditions. The study was testing the hypothesis that repeated atrazine application to soil will not result in enhanced atrazine mineralization. The study was carried out with 14C-uniformly ring-labeled atrazine in a laboratory under controlled conditions. Atrazine mineralization to 14CO2 in soil with no history of atrazine use was negligible (0.16%) after 163 days of soil incubation. The three metabolites hydroxyatrazine, desisopropylatrazine, and desethylatrazine in the proportion of 17.7%, 1.3%, and 2.6%, respectively, were in the soil after 75 days. In the soil from the sugarcane-cultivated field with history of atrazine use, atrazine mineralization was 89.9% after 98 days. The same soil, amended with mature compost, showed a lag phase of eight days before rapid atrazine mineralization was observed. 相似文献
8.
The formation and fate of chlorinated organic substances in temperate and boreal forest soils 总被引:1,自引:0,他引:1
Nicholas Clarke Květoslava Fuksová Milan Gryndler Zora Lachmanová Hans-Holger Liste Jana Rohlenová Reiner Schroll Peter Schröder Miroslav Matucha 《Environmental science and pollution research international》2009,16(2):127-143
Background, aim and scope Chlorine is an abundant element, commonly occurring in nature either as chloride ions or as chlorinated organic compounds
(OCls). Chlorinated organic substances were long considered purely anthropogenic products; however, they are, in addition,
a commonly occurring and important part of natural ecosystems. Formation of OCls may affect the degradation of soil organic
matter (SOM) and thus the carbon cycle with implications for the ability of forest soils to sequester carbon, whilst the occurrence
of potentially toxic OCls in groundwater aquifers is of concern with regard to water quality. It is thus important to understand
the biogeochemical cycle of chlorine, both inorganic and organic, to get information about the relevant processes in the forest
ecosystem and the effects on these from human activities, including forestry practices. A survey is given of processes in
the soil of temperate and boreal forests, predominantly in Europe, including the participation of chlorine, and gaps in knowledge
and the need for further work are discussed.
Results Chlorine is present as chloride ion and/or OCls in all compartments of temperate and boreal forest ecosystems. It contributes
to the degradation of SOM, thus also affecting carbon sequestration in the forest soil. The most important source of chloride
to coastal forest ecosystems is sea salt deposition, and volcanoes and coal burning can also be important sources. Locally,
de-icing salt can be an important chloride input near major roads. In addition, anthropogenic sources of OCls are manifold.
However, results also indicate the formation of chlorinated organics by microorganisms as an important source, together with
natural abiotic formation. In fact, the soil pool of OCls seems to be a result of the balance between chlorination and degradation
processes. Ecologically, organochlorines may function as antibiotics, signal substances and energy equivalents, in descending
order of significance. Forest management practices can affect the chlorine cycle, although little is at present known about
how.
Discussion The present data on the apparently considerable size of the pool of OCls indicate its importance for the functioning of the
forest soil system and its stability, but factors controlling their formation, degradation and transport are not clearly understood.
It would be useful to estimate the significance and rates of key processes to be able to judge the importance of OCls in SOM
and litter degradation. Effects of forest management processes affecting SOM and chloride deposition are likely to affect
OCls as well. Further standardisation and harmonisation of sampling and analytical procedures is necessary.
Conclusions and perspectives More work is necessary in order to understand and, if necessary, develop strategies for mitigating the environmental impact
of OCls in temperate and boreal forest soils. This includes both intensified research, especially to understand the key processes
of formation and degradation of chlorinated compounds, and monitoring of the substances in question in forest ecosystems.
It is also important to understand the effect of various forest management techniques on OCls, as management can be used to
produce desired effects. 相似文献
9.
Sebastian Gayler Stefan Trapp Michael Matthies Reiner Schroll Herwart Behrendt 《Environmental science and pollution research international》1995,2(2):98-103
The uptake of terbuthylazine and its medium polar metabolites into maize plants under outdoor conditions is investigated.
For this purpose, a dynamical fate model consisting of soil, plant and air is developed. The model calculations are compared
with experimental results of outdoor lysimeter tests, carried out with14C-labelled herbicide applied to sandy agricultural soil at a single application rate of 890 g/ha. Approximately 0.3 % of the
applied activity remains in all the plants after the vegetation period. The model predicts that about three times that amount
is volatilized from the plants into the air. Activity uptaken from soil and volatilized from plant surface into air is predominately
associated with metabolites. During the whole vegetation period the fraction of unchanged terbuthylazine in the plants is
very small (less than 1 % of the extractable activity). 相似文献
10.
Laturnus F Fahimi I Gryndler M Hartmann A Heal MR Matucha M Schöler HF Schroll R Svensson T 《Environmental science and pollution research international》2005,12(4):233-244
- DOI: http:/dx.doi.org/10.1065/espr2005.06.262
Goal, Scope and Background The anthropogenic environmental emissions of chloroacetic acids and volatile organochlorines have been under scrutiny in
recent years because the two compound groups are suspected to contribute to forest dieback and stratospheric ozone destruction,
respectively. The two organochlorine groups are linked because the atmospheric photochemical oxidation of some volatile organochlorine
compounds is one source of phytotoxic chloroacetic acids in the environment. Moreover, both groups are produced in higher
amounts by natural chlorination of organic matter, e.g. by soil microorganisms, marine macroalgae and salt lake bacteria,
and show similar metabolism pathways. Elucidating the origin and fate of these organohalogens is necessary to implement actions
to counteract environmental problems caused by these compounds.
Main Features While the anthropogenic sources of chloroacetic acids and volatile organochlorines are relatively well-known and within human
control, knowledge of relevant natural processes is scarce and fragmented. This article reviews current knowledge on natural
formation and degradation processes of chloroacetic acids and volatile organochlorines in forest soils, with particular emphasis
on processes in the rhizosphere, and discusses future studies necessary to understand the role of forest soils in the formation
and degradation of these compounds.
Results and Discussion Reviewing the present knowledge of the natural formation and degradation processes of chloroacetic acids and volatile organochlorines
in forest soil has revealed gaps in knowledge regarding the actual mechanisms behind these processes. In particular, there
remains insufficient quantification of reliable budgets and rates of formation and degradation of chloroacetic acids and volatile
organochlorines in forest soil (both biotic and abiotic processes) to evaluate the strength of forest ecosystems regarding
the emission and uptake of chloroacetic acids and volatile organochlorines, both on a regional scale and on a global scale.
Conclusion It is concluded that the overall role of forest soil as a source and/or sink for chloroacetic acids and volatile organochlorines
is still unclear; the available laboratory and field data reveal only bits of the puzzle. Detailed knowledge of the natural
degradation and formation processes in forest soil is important to evaluate the strength of forest ecosystems for the emission
and uptake of chloroacetic acids and volatile organochlorines, both on a regional scale and on a global scale.
Recommendation and Perspective As the natural formation and degradation processes of chloroacetic acids and volatile organochlorines in forest soil can
be influenced by human activities, evaluation of the extent of this influence will help to identify what future actions are
needed to reduce human influences and thus prevent further damage to the environment and to human health caused by these compounds. 相似文献