共查询到20条相似文献，搜索用时 330 毫秒
1.
The spatial variability in mineralization of atrazine, isoproturon and metamitron in soil and subsoil samples taken from a 135-ha catchment in north France was studied. Fifty-one samples from the top layer were taken to represent exhaustively the 31 agricultural fields and 21 soil types of the catchment. Sixteen additional samples were collected between depths of 0.7 and 10 m to represent the major geological materials encountered in the vadose zone of the catchment. All these samples were incubated with 14C-labelled atrazine under laboratory conditions at 28 degrees C. Fourteen selected surface samples which exhibited distinctly different behaviour for atrazine dissipation (including sorption and mineralization) were incubated with 14C-isoproturon and 14C-metamitron. Overall soil microbial activity and specific herbicide degradation activities were monitored during the incubations through measurements of total carbon dioxide and 14C-carbon dioxide respectively. At the end of the incubations, extractable and non-extractable (bound) residues remaining in soils were measured. Variability of herbicide dissipation half-life in soil surface samples was lower for atrazine and metamitron (CV < 12%) than for isoproturon (CV = 46%). The main contributor to the isoproturon dissipation variability was the variability of the extractable residues. For the other herbicides, spatial variability was mainly related to the variability of their mineralization. In all cases, herbicide mineralization half-lives showed higher variability than those of dissipation. Sorption or physicochemical soil properties could not explain atrazine and isoproturon degradation, whose main factors were probably directly related to the dynamics of the specific microbial degradation activity. In contrast, variability of metamitron degradation was significantly correlated to sorption coefficient (K(d)) through correlation with the sorptive soil components, organic matter and clay. Herbicide degradation decreased with depth as did the overall microbial activity. Atrazine mineralization activity was found down to a depth of 2.5 m; beyond that, it was negligible. 相似文献
2.
Robert M Zablotowicz L Jason Krutz Cesare Accinelli Krishna N Reddy 《Pest management science》2009,65(6):658-664
BACKGROUND: The objectives of these laboratory experiments were: (1) to assess bromoxynil sorption, mineralization, bound residue formation and extractable residue persistence in a Dundee silt loam collected from 0–2 cm and 2–10 cm depths under continuous conventional tillage and no‐tillage; (2) to assess the effects of autoclaving on bromoxynil mineralization and bound residue formation; (3) to determine the partitioning of non‐extractable residues; and (4) to ascertain the effects of bromoxynil concentration on extractable and bound residues and metabolite formation. RESULTS: Bromoxynil Kd values ranged from 0.7 to 1.4 L kg?1 and were positively correlated with soil organic carbon. Cumulative mineralization (38.5% ± 1.5), bound residue formation (46.5% ± 0.5) and persistence of extractable residues (T1/2 < 1 day) in non‐autoclaved soils were independent of tillage and depth. Autoclaving decreased mineralization and bound residue formation 257‐fold and 6.0‐fold respectively. Bromoxynil persistence in soil was rate independent (T1/2 < 1 day), and the majority of non‐extractable residues (87%) were associated with the humic acid fraction of soil organic matter. CONCLUSIONS: Irrespective of tillage or depth, bromoxynil half‐life in native soil is less than 1 day owing to rapid incorporation of the herbicide into non‐extractable residues. Bound residue formation is governed principally by biochemical metabolite formation and primarily associated with soil humic acids that are moderately bioavailable for mineralization. These data indicate that the risk of off‐site transport of bromoxynil residues is low owing to rapid incorporation into non‐extractable residues. Published 2009 by John Wiley & Sons, Ltd 相似文献
3.
The mobility and retention of atrazine and dicamba in six Atlantic Coastal Plain soils were estimated by soil thin-layer chromatography (soil-TLC). The soils studied were representative of the major agricultural regions in Delaware and were sampled, by horizon, to the water table. Four horizons from each profile were leached simultaneously with distilled water on one soil-TLC plate. Two values were obtained from each plate: the ratio of the distance traveled by the herbicide center of mass over that traveled by the solvent front (Rm), and a sorption distribution coefficient (Kd). The Rm values ranged from 0·06 to 0·94 for atrazine and from 0·80 to 0·94 for dicamba. Herbicide mobility was found to be greatest in coarse-textured soil horizons that contained low levels of organic matter, clay, and Fe and Al oxides. Correlation analysis indicated that effective cation exchange capacity, exchangeable acidity, exchangeable aluminum, and clay were useful predictive variables or both atrazine mobility and sorption. Organic matter was not useful for predicting soil-TLC derived sorption estimates; however, it was correlated to Kd-batch estimates. Distribution coefficients calculated from soil-TLC data were found to be in general agreement with Kd values obtained for the same soils by batch equilibrium techniques. The average Kd-soil-TLC values for atrazine and dicamba were 2·09(±2·24) and 0·03(±0·02), respectively. The ratio of the batch Kd to the soil-TLC Kd ranged from 0·1 to 19 (x̄=1·6, SD=3·8) for atrazine and from 2·9 to 38 (x̄=12·6, SD=8·7) for dicamba. Thus, although for some horizons agreement between the two methods was good, for other horizons significant discrepancies existed. It is suggested that the soil-TLC gives results under non-equilibrium conditions, whereas the batch procedure is, by definition, at quasi-equilibrium. These fundamental differences may account for the observed differences between the two methods. It is also suggested that, due to this difference, the soil-TLC procedure can provide additional information relevant to herbicide partitioning in the field environment that is not provided by traditional batch equilibrium techniques. © 1998 Society of Chemical Industry 相似文献
4.
The transformations of eight herbicides (atrazine, simazine, terbutryn, pendimethalin, carbetamide, 2,4-D, metsulfuron-methyl and dimefuron) in soil after compost addition were monitored during long-term laboratory incubations. The herbicides were applied to soil, compost and soil-compost mixtures. Herbicide sorption, their kinetics of mineralisation and the extractability of residues were compared in the different treatments. Compost addition to soil generally decreased herbicide mineralisation and favoured the stabilisation of herbicide residues. A fraction of the stabilised residues remained extractable and potentially available. However, most of them were unextractable and formed bound residues. Sorption could be at the origin of a kinetically limited biodegradation, mainly for the most highly-sorbed herbicides (atrazine, simazine, terbutryn, pendimethalin and dimefuron). Compost addition had little effects on the less sorbed herbicides (carbetamide, 2,4-D and metsulfuron- methyl). © 1997 SCI. 相似文献
5.
A soil column experiment under outdoor conditions was performed to monitor the fate of 14C-ring-labelled sulcotrione, 2-(2-chloro-4-mesylbenzoyl)cyclohexane-1,3-dione and atrazine, 6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine, in water leachates and in the ploughed horizon of a sandy loam soil. Two months after treatment, the cumulative amounts of herbicide residues leached from the soil were 14.5% and 7% of the applied radioactivity for sulcotrione and atrazine, respectively. Maximum leachate concentrations for each herbicide were observed during the first month following application: 120 and 95 microg litre(-1) for sulcotrione and atrazine respectively. After 2 weeks, 78% of the sulcotrione and atrazine was extractable from the soil, whereas after two months only 10 and 4%, respectively, could be extracted. The maximum sulcotrione content in the first 10 cm of soil was identical with that of atrazine. For both molecules, the content of non-extractable residues was low, being around 15%. Sulcotrione seems to be more mobile than atrazine but the consequences for water contamination are similar since lower doses are used. 相似文献
6.
7.
The metabolism of atrazine in soil was studied in two maize fields located in regions with different soil types. Treatments were cow manure or pig slurry (50 tonnes each ha-1) applied once either in March or in November before sowing, or green manure incorporated in March. Control plots were not treated with organic fertilizers. Atrazine at 0.75 or 1.0 kg a.i. ha-1 was applied after sowing. In the 0-12 cm soil layer, the main atrazine metabolites found were deethylatrazine and hydroxyatrazine. Low concentrations of deisopropylatrazine and 6-chloro-1, 3, 5-triazine-2, 4-diamine were also observed. During the 4 months after sowing, the organic fertilizers decreased the rate of atrazine degradation, but subsequently there were no differences between treated and control plots. At harvest, the concentrations of atrazine and its metabolites were very low and similar in all plots. The organic fertilizers thus did not cause atrazine metabolites to accumulate in soil. In addition, atrazine and its metabolites were never detected below 12 cm in any of the plots. 相似文献
8.
Rates of pesticide degradation in soil exhibit a high degree of variability, the sources of which are usually unclear. Combining data from incubations performed using a range of soil properties and environmental conditions has resulted in greater understanding of factors controlling such degradation. The herbicides clomazone, flumetsulam, atrazine, and cloransulam-methyl, as well as the former insecticide naphthalene offer examples of degradation kinetics controlled by coupling competing processes which may in turn be regulated separately by environmental conditions and soil properties. The processes of degradation and volatilization appear to compete for clomazone in solution; sorbed clomazone is degraded only after the solution phase is depleted. Similarly, volatilization of naphthalene is enhanced when degradation has been inhibited by high nutrient levels. Degradation of the herbicide flumetsulam has been shown to be regulated by sorption, even though the compound has a relatively low affinity for the soil. The fate pathway for cloransulam-methyl shifts from mineralization to formation of metabolities, bound residues and physically occluded material as temperature increases. Atrazine degradation in soil may be controlled in part by the presence of inorganic nitrogen, as the herbicide appears to be used as a nitrogen source by micro-organisms. New insight gained from measurement of multiple fate processes is demonstrated by these examples. 相似文献
9.
Tomasz Golab C.E. Bishop A.L. Donoho J.A. Manthey L.L. Zornes 《Pesticide biochemistry and physiology》1975,5(2):196-204
Radiochemical studies of field soil treated with 14C oryzalin (3,5-dinitro-N4,N4-dipropylsulfanilamide) indicated that the compound was readily degradable. One year after soil treatment with oryzalin, 45% of the original radioactivity had dissipated, 25% was extractable, and 30% was “soil bound”. The extractable fraction contained oryzalin and several degradation products, some of which were isolated and identified. No single degradation product accounted for more than 3% of the applied oryzalin. The “soil-bound” radioactivity was extractable with hot alkali. No significant radioactive residues were detectable in either seed or forage of soybean and wheat plants. No specific metabolites of oryzalin were identified in soybean plants. Trace amounts of radioactivity found in plant tissue appeared to be associated with the various plant constituents. 相似文献
10.
Jian Lu Ruirui Li Yuansen Chang Yang Zhang Nan Zhang Liming Tao Wenping Xu 《Journal of Pesticide Science》2021,46(2):214
Atrazine is the most extensively used herbicide in the agricultural and forestry sectors. Nevertheless, along with the increasing usage amount of Atrazine, its harm exposed gradually, the main problem is its residues in the environment. Microbial adsorption may effectively reduce the pollution caused by atrazine residue in the environment. In this study, a strain of fungi with the function of adsorbing atrazine was selected using microbial screening technology. According to its phenotypic characteristics and 18S rDNA gene sequencing, this strain was of the species genus Aspergillus and was named ECUST-TXZC2018. By studying the dynamic adsorption effect of this strain on atrazine, we found that this strain adsorbed atrazine after 36 hr at pH=5–7, and 20–30°C with more than 70% adsorption. These results demonstrated that ECUST-TXZC2018 had potential application ability to control atrazine residue pollution through the biosorption function. 相似文献
11.
Residual effects of chlorotriazine herbicides in soil at three Rumanian sites. II. Prediction of the phytotoxicity of atrazine residues to following crops Total and plant-available atrazine residues in the top 10 cm soil were measured 120 days after application of 3 kg ai ha?1 to maize (Zea mays L.) at three sites in Rumania. At one site, similar measurements were made 3?5 years after application of 100 kg ai ha?1. Plant-available atrazine residues were estimated by extraction of soil samples with water, and by bioassay using Brassica rapa as the test plant. It was calculated that between 30 and 120μg atrazine 1?1 was potentially available to plants in the different soils. Dose-response relationships for atrazine and the most important rotational crops with maize in Rumania—sunflower, winter wheat, soybean and flax—were determined in hydroponic culture using herbicide concentrations corresponding with the plant-available fractions measured in the different soils. ED50 values were determined by probit analysis and the results showed that sunflower (ED50, 22μg 1?1) was the most sensitive crop, and soybean (ED50, 78μg 1?1) was the least. The residual phytotoxicity of atrazine to succeeding crops in the different soils was predicted using the appropriate availability and phytotoxicity data, and the results showed good agreement with those observed. The results suggest that measurements of plant-available herbicide residues afford a rapid method of assessing possible phytotoxicity to following crops. 相似文献
12.
Raymond J. Hance 《Pest management science》1979,10(1):83-86
The rates of disappearance of atrazine, dichlorprop, linuron and propyzamide were measured in two soils incubated at 22°C and 80% water holding capacity. Observations were made at four pH levels in each soil. Atrazine degradation was relatively insensitive to pH; it increased slightly with increasing pH in one soil and decreased in the other. The other compounds all degraded more slowly at low pH in both soils although dichlorprop had essentially disappeared in 14 days under all conditions, so that the effect of pH is not unlikely to be of practical interest. The ratios of the degradation rates of atrazine, linuron, and propyzamide varied with the soil and the pH. 相似文献
13.
The role of the leaves of Robinia pseudoacacia L., which is widely distributed in the arid lands, on improving soil physical and chemical properties was analyzed at various incubation periods. The incubated soils added with 0, 25, 50 and 75 g Robinia pseudoacacia leaves were tested after consecutive incubation intervals of 6, 8 and 10 months and the different soil parameters were measured. The results showed the increases in organic matter (OM), extractable K, cation exchange capacity (CEC), aggregate stability and water holding capacity, but the decreases in pH value and bulk density after 6 months’ incubation. The gradual decrease in change rates of soil properties indicated less microbial population and organic residual mineralization under acidic conditions, which were resulted from fast decomposition of leaves after the first 6 months incubation. The increases in soil organic matter content, extractable K, CEC, aggregate stability and water holding capacity and the decreases in soil pH and bulk density provide favorable conditions for crop’s growth. 相似文献
14.
Degradation if isoproturon and availability of residues in soil The availability and degradation of 14C-ring-labelled isoproturon in soil was investigated over 140 days under controlled laboratory conditions. Degradation of the active ingredient followed and 65 days later only a minor fraction (0.6%) of the parent molecule remained extractable. A demethylated-isoproturon metabolite was detectable in soil from day 15 (2.6%). The amount of 14CO2 derived from the 14C benzene ring label and liberated over time indicated that a total of 13.6% isoproturon was mineralized during the incubation period. In parallel, the amount of 14C residue extracted from the soil by water followed by methanol or remaining within the soil—analysed by combustion—was also determined at intervals. After 140 days, 72% of the radiolabel added remained in the soil as non-extractable residue. The degradation half-life of extractable isoproturon was an estimated 14 days. 相似文献
15.
水分对不同栽培年限日光温室土壤氮矿化的影响 总被引：1，自引：0，他引：1
采用室内短期（84 d）好气培养法评价了不同水分供应水平下（田间持水量的60%、80%及100%,分别用60FC、80FC和100FC表示）陕西杨凌地区不同栽培年限（种植前、种植第二年及种植第三年）日光温室土壤（0~20 cm及20~40 cm土层）氮素矿化特性。结果表明：随着日光温室栽培年限的延长,0~20 cm土层累积净矿化氮量显著增加,且随栽培年限的增加,20~40 cm 土层氮矿化势呈增加的趋势;土壤水分含量由60FC增加到80FC,土壤累积矿化氮量呈增加趋势,但当含水量达到100FC时,土壤累积矿化氮量降低。回归分析结果表明,土壤有机质含量每增加1 g·kg-1, 60FC、80FC、100FC土壤含水量条件下土壤氮矿化势分别增加 1.62、1.88 mg·kg-1和1.57 mg·kg-1;土壤全氮含量每增加1 g·kg-1,土壤氮矿化势分别增加28.93、33.42 mg·kg-1和27.82 mg·kg-1。因此,建议日光温室蔬菜栽培中应综合考虑温室年限及灌溉量对土壤氮素矿化过程的影响。 相似文献
16.
This study was conducted to evaluate short- and long-term effects of poultry and sheep manures, as well as sunflower, canola, and potato residues, which commonly are being used as organic amendments (OAs) in agricultural soils, on the pH value, buffering capacity, and nitrogen (N) turnover of a sub-alkaline agricultural soil using laboratory incubation. The tested OAs had pH values ranging from alkaline (manures) to acidic (plant residues), and their effects of the short- and log-term on soil pH value were assessed by fractionation of the OAs alkalinity and evaluating the contribution of OA-borne N mineralization to soil acidity. On average, 45% of potential alkalinity in tested OAs was available for acid-base reactions, soluble alkalinity accounted for 58, 80, 32, 50, and 50% of the excess cations for poultry manure, sheep manure, sunflower, canola, and potato residues, respectively. Buffering capacity of the tested OAs was higher for sunflower residues, potato residues, and poultry manure and lower for canola residues and sheep manure. The tested OAs showed different N mineralization potential, and during the 100 days of incubation, soils amended with sheep manure, poultry manure, and potato residues released 107, 118, 129, and 240?mg?N?kg?1 soil, respectively, more than double than that released from unamended soil. Our results demonstrated that long-term impact of OAs on the soil pH value is not related to the initial OAs pH value and soluble alkalinity and that available alkalinity and N mineralization are key factors regulating the soil pH value on the long-term. 相似文献
17.
土壤中烟嘧磺隆和莠去津残留对甘薯的药害评价 总被引：2，自引：0，他引：2
为了明确玉米田除草剂烟嘧磺隆和莠去津土壤残留对后茬作物甘薯生长的影响,于2017年分别在河北省保定满城区、文安县、霸州市和石家庄藁城区采集甘薯田土壤样品,采用QuEChERS法,结合超高效液相色谱-串联质谱法 (UPLC-MS/MS) 测定了土壤中烟嘧磺隆和莠去津的残留量;通过盆栽试验,测定了烟嘧磺隆、莠去津以及二者混用对甘薯的药害作用。结果表明:在甘薯药害表现严重的河北保定满城区、文安县、霸州市3地甘薯田土壤中烟嘧磺隆的残留量在11.80~87.97 μg/(kg土) 之间,莠去津残留量在2.71~8.40 μg/(kg土) 之间;而在石家庄藁城区无药害症状甘薯田土壤中只检测到莠去津,含量在3.43~4.42 μg/(kg土) 之间。盆栽试验结果表明,栽后20 d每千克甘薯田土壤中烟嘧磺隆含量大于1 μg时,甘薯产生药害症状;烟嘧磺隆对甘薯根系IC50值为3.74 μg/(kg土),IC10值为1.27 μg/(kg土)。土壤中莠去津含量在2~40 μg/(kg土) 范围内,对甘薯茎叶和根系没有可见药害症状,但对根系生长具有轻微抑制作用。烟嘧磺隆与莠去津按质量比10 : 1、5 : 1、5 : 2和5 : 5混用对甘薯药害有一定的拮抗作用,共毒系数CTC50值分别为66.25、59.16、61.30和79.47。烟嘧磺隆对甘薯药害症状主要表现为植株矮小,叶片小,整株或心叶黄化,根系发育受阻,侧根短粗。生产上造成甘薯药害的诱因是土壤中残留的烟嘧磺隆,对甘薯药害阈值为1 μg/(kg土)。 相似文献
18.
Md. Ruhul Amin M. A. Malek Mostafizur Rahman Enamul Hoque 《Pest management science》1998,52(2):152-158
Enzyme immunoassay (EIA) has been tested for the detection of atrazine in soil and water. EIA kits and atrazine-fortified samples were received from the International Atomic Energy Agency. Atrazine concentrations of about 0·01 μg litre-1 could be detected and the central detection point was found at about 0·15 μg litre-1 which is a reasonably sensitive region for atrazine. A validation study with spiked local water samples yielded acceptable results. No treatment was required for water samples. Extraction of atrazine from soil was done by simple shaking with methanol without any clean-up steps. Detection limits of 1×10-2 μg litre-1 for water and 5×10-3 μg kg-1 for soil were achieved. © 1998 SCI. 相似文献
19.
The aim of this study was to investigate the spatial variability in degradation and mineralization of atrazine and isoproturon in subsurface samples taken from sandy loam soils overlying gravel terraces which form part of a groundwater protection zone. Percussion drilling was used to obtain samples from 11 boreholes (maximum depth 3 m). Unlabelled atrazine or isoproturon, and ring-14C-labelled atrazine or isoproturon were added to samples, incubated at 25 degrees C for up to 16 weeks, and analyzed for the residual herbicide or [14C]carbon dioxide. All samples showed the potential to degrade these herbicides, although the percentage degradation decreased by a factor of 2-3 from the surface soil to a depth of 3 m. This was associated with a decrease in organic matter content, but there was no change in the potential to mineralize acetate, indicating that specific changes in the catabolic ability of the microbial population occurred with depth. The capacity of samples to mineralize atrazine and isoproturon to carbon dioxide decreased markedly with depth, with no mineralization potential observed at a depth of 80 cm. 相似文献
20.
Abdellah Yassir Bernard Lagacherie Sabine Houot Guy Soulas 《Pest management science》1999,55(8):799-809
Among 15 soils with different cropping practices, seven which had an history of repeated atrazine applications showed accelerated degradation of this herbicide. By contrast, grassland or agricultural soils with no recorded atrazine application, at least for the last three years, had a low degradation potential. No direct relation was found between the rate of atrazine mineralisation and the size of the microbial biomass. In adapted soils, the amounts of extractable residues were lowered and the very high percentages of radioactivity from [ring-14C]atrazine recovered as [14C]carbon dioxide demonstrated that N-dealkylation and deamidation were the only processes for micro-organisms to derive carbon and energy for heterotrophic growth. Kinetics of microbial 14C accumulation revealed that atrazine ring carbon could be incorporated by direct oxidative condensation with structural components of the bacterial or fungal cell whereas side-chain carbon was preferentially used for biosynthesis of new protoplasmic cell material, as confirmed by the high turnover rate of radiolabelled microbial components. From the determination of the Michaelis–Menten parameters, Vm and Km in the presence of different selective biocides, it was possible to conclude that fungi were probably less active in atrazine degradation than bacteria and that over years the microbial atrazine-degrading community showed an increased efficiency. © 1999 Society of Chemical Industry 相似文献