The Experts below are selected from a list of 24498 Experts worldwide ranked by ideXlab platform
Kadambot H. M. Siddique - One of the best experts on this subject based on the ideXlab platform.
-
combined ditch buried straw return technology in a ridge furrow Plastic Film mulch system implications for crop yield and soil organic matter dynamics
Soil & Tillage Research, 2020Co-Authors: Duanpu Song, Pengfei Dang, Lina Wei, Xiaoliang Qin, Kadambot H. M. SiddiqueAbstract:Abstract A ridge–furrow Plastic Film mulch (RP) configuration can increase crop and straw yields in semiarid areas of China. This study advocated for a novel soil tillage practice (ditch buried straw return) in a ridge–furrow Plastic Film mulch system. There were three treatments: (i) flat cultivation, CK; (ii) ridge–furrow Plastic Film mulch with no straw return (RP−S); and (iii) ridge–furrow Plastic Film mulch with ditch buried straw return (RP+S). Field experiments were conducted from 2015 to 2018 on the Loess Plateau of China to study the effects of straw incorporation on maize growth, biomass, water use efficiency, soil organic carbon, and total nitrogen sequestration capacity in RP systems. The mean rate of straw decomposition in RP+S reached 81 % at harvest of each year. The RP systems provided suitable hydrothermal conditions for maize growth. Both RP treatments promoted maize growth, particularly biomass accumulation and plant height under RP+S. The RP+S treatment also had greater concentrations of soil organic carbon and total nitrogen in surface soil at harvest, higher total nitrogen accumulation, nitrogen content and crude protein in maize grain, and higher maize yields and water use efficiencies than the other two treatments. In summary, the introduction of ditch buried straw return to RP is an effective measure for promoting the sustainable development of Film mulching systems in semiarid regions of China by improving soil fertility and increasing crop yields.
-
Alfalfa forage yield, soil water and P availability in response to Plastic Film mulch and P fertilization in a semiarid environment
Field Crops Research, 2018Co-Authors: Cheng-long Han, Jing-wei Fan, Xiao-peng Shi, Meng Kong, Xiao-yan Shi, Kadambot H. M. Siddique, Yangyang ZhaoAbstract:Abstract Alfalfa (Medicago sativa L.) is an important forage legume in farming and animal husbandry systems in semiarid areas. However, its forage yields in dryland farming areas are usually very low due to water shortages and low soil phosphorus (P) availability. This study assessed the effects of Plastic Film mulch and P fertilization on alfalfa forage yield and shoot P uptake in response to improved soil moisture and soil P availability in a dryland farming system of northwest China. A six-year field experiment, which commenced in 2011, was conducted at Yuzhong County, Gansu Province, China in randomized blocks of split-plot design with two mulch treatments—Plastic Film mulch with ridge and furrow (M) and no Plastic Film mulch with flat planting (NM)—as the main plots, and four P levels—0, 9.73, 19.3, 28.9 kg P ha−1—as split plots. Alfalfa forage yield and shoot P uptake and concentration increased linearly with increasing P level in the NM treatment. In the M treatment, shoot P concentration also increased linearly with increasing P level, but shoot P uptake and forage yield were well-fitted by a quadratic model with P level as the independent variable and a lower physiological P use efficiency at high P level. Alfalfa forage yield and water use efficiency increased with Plastic Film mulch. Soil water content in the upper 1 m of soil increased with Plastic Film mulch and was higher in the 2014 growing season and in April 2015 due to more rainfall. However, at 1–5 m soil depth, the soil water content decreased with Plastic Film mulch and P fertilization but increased at high P levels with Plastic Film mulch. Soil pH decreased with Plastic Film mulch and P fertilization, with a stronger effect from the latter, which is beneficial for improving soil P availability. Soil available P, mostly derived from inorganic P, increased with P fertilization and was lower in M than NM treatments due to alfalfa uptake and competition with soil microorganisms. We concluded that Plastic Film mulch and P fertilization, of about 16.1 or 17.5 kg P ha−1, was an appropriate combination to improve soil water condition and soil P availability for increased alfalfa forage yield or shoot P uptake in this semiarid region.
-
multi site assessment of the effects of Plastic Film mulch on the soil organic carbon balance in semiarid areas of china
Agricultural and Forest Meteorology, 2016Co-Authors: Yong Peng Wang, Neil C Turner, Lin Wang, Kadambot H. M. SiddiqueAbstract:Abstract Plastic-Film mulch is widely used to increase soil temperature and reduce water evaporation in vegetable production. In China, it is also extensively used for growing grain crops, especially in temperature and rainfall limited areas. However, it remains unclear whether the technology is sustainable in terms of maintenance of soil organic carbon (SOC) balance. We assessed the effects of Plastic-Film mulch on the SOC balance in maize (Zea mays L.) production in a range of cold semiarid environments. We imposed four treatments: (i) no Plastic-Film mulch or straw incorporation, (ii) Plastic-Film mulch, (iii) straw incorporation in soil without mulch, and (v) straw incorporation plus mulch, in ridge–furrow prepared fields at five sites along a hydrothermal gradient for up to six years. Maize root biomass across sites increased by 23–38% in mulched plots associated with the increase in aboveground biomass, indicating an increased SOC input, compared to that in non-mulched plots. The Plastic-Film mulch increased SOC mineralization, indicated by the stimulated decomposition of buried maize straw, and a 4–5% reduction in the concentration of light-fraction SOC (
-
multi site assessment of the effects of Plastic Film mulch on dryland maize productivity in semiarid areas in china
Agricultural and Forest Meteorology, 2016Co-Authors: Yong Peng Wang, Neil C Turner, Jing Zhu, Cheng Yun Fan, Xue Jing Kong, Kadambot H. M. SiddiqueAbstract:Transparent Plastic-Film mulch combined with ridge-furrow technology is widely used to improve crop productivity in cold semiarid areas of China, but whether the technology has similar benefits in different climatic environments is not known. The present study was initiated to assess the variation of Plastic-Film mulch on maize (Zea mays L.) production in different semiarid environments. Four treatments: (i) Plastic-Film mulch, (ii) straw incorporation in soil without Plastic-Film mulch, (iii) straw incorporation plus Plastic-Film mulch, and (iv) no Plastic-Film mulch or straw incorporation (control) were imposed in ridge-furrow prepared fields at five sites along a hydrothermal gradient for up to 6 years. Compared to non-mulched plots, maize grain yield and aboveground biomass in mulched plots increased by 30–107% and 37–69%, respectively, across sites due to increased soil temperature and moisture principally during early growth. Plastic mulch increased grain yield to a greater extent at sites with higher hydrothermal limitations. Plastic mulch increased the harvest index of maize at cooler sites, but showed a decrease in harvest index at warmer sites, compared with no mulch. The mulch decreased the year-to-year variation in maize yield at the more hydrothermally-limited sites, but increased the variation at less hydrothermally-limited sites. Compared to no straw incorporation, straw incorporation increased grain yield and aboveground biomass by 7–12% and 8–12%, respectively, across the five sites. The present study suggests that the benefits of Plastic-Film mulch on maize grain yield and its stability varied significantly with local climatic conditions and that Plastic-Film mulch can be preferentially applied for maize production where both insufficient rainfall and low spring temperatures are limiting factors.
-
effects of water management with Plastic Film in a semi arid agricultural system on available soil carbon fractions
European Journal of Soil Biology, 2013Co-Authors: Changan Liu, Limin Zhou, Qi Feng, Chengchen Pan, Le Wang, Jiling Chen, Yu Jia, Kadambot H. M. SiddiqueAbstract:Abstract There is little information regarding the sustainability of the high yield agroecosystem with double ridges and furrows mulched with Plastic Film in semi-arid areas. In this study, we explored the sustainability of this agroecosystem with different mulching time during two growing seasons over 2006 and 2007. Three treatments were designed: (i) Plastic Film mulching applied at sowing and Film removed at harvest (CK); (ii) mulching applied 30 days before sowing and removed at harvest (M1); and (iii) mulching applied at sowing and Film left on field after harvest and used continually for mulching in the second season (M2). Microbial biomass C (MBC) and ratio of MBC to soil organic C (SOC) (MBC/SOC) were higher in M1 and M2 than in CK in 2007 growing season. The reduction rates of the ratios of light fraction of organic C (LFOC) to SOC (LFOC/SOC) with sampling dates were 0.0020, 0.0047 and 0.0045 for CK, M1 and M2, respectively. A larger value means a faster reduction rate of LFOC/SOC with sampling dates, and implying farming system would face a higher unsustainable risk. MBC correlated negative significantly with LFOC ( R = −0.939, P = 0.0001) and mineral N ( R = −0.835, P = 0.0007) due to low soil C pool. Accordingly, Film mulched ridge and furrow system would threaten the sustainability of soil ecosystem via MBC increase a semi-arid agroecosystem. The practices of mulching applied 30 d before sowing (M1) and use of Plastic Film once every two years (M2) lead to increased environmental risk for the farming system.
Zhaohui Wang - One of the best experts on this subject based on the ideXlab platform.
-
Plastic Film mulch increased winter wheat grain yield but reduced its protein content in dryland of northwest china
Field Crops Research, 2018Co-Authors: Laichao Luo, Zhaohui Wang, Ming Huang, Xiaoli Hui, Sen Wang, Yue Zhao, Xiang Zhang, Chaopeng Diao, Hanbing CaoAbstract:Abstract Plastic Film mulch has been proved of great potential to enhance crop productivities in drylands, but there is still lacking insight into its underlying changes in crop grain nutritional quality. Therefore, field experiments were conducted to investigate the effects of different soil surface managements on grain yield and its protein content of winter wheat in 2014–2016 at different fertilizer input levels under no mulch and Plastic Film mulch at seven sites in dryland of the Loess Plateau in northwest China. Compared with no mulch, overall average grain yield was significantly increased by 13.7%, but its protein content was decreased by 7.8% with Plastic Film mulch. Apart from the dilution effects caused by the much more increase of grain yield, the decreased N remobilization from vegetative parts to grain and the lowered crop N uptake from soil during grain filling stage were found to be the main reasons, when the overall average of N remobilization efficiency, N harvest index and post-anthesis N uptake was respectively decreased by 16.0%, 5.7% and 24.0%. However, the winter wheat grain protein content was observed to increase more quickly with the N rate increase under Plastic Film mulch, compared to no mulch. This provides opportunity to increase the grain protein content under Plastic Film mulch to the same level of no mulch by increasing the N fertilizer application rates, and an estimation of optimal N application rates for winter wheat grain yield and its protein content was computed under Plastic Film mulch in drylands.
-
effects of Plastic Film combined with straw mulch on grain yield and water use efficiency of winter wheat in loess plateau
Field Crops Research, 2015Co-Authors: Yanlong Chen, Ting Liu, Xiaohong Tian, Xiaofeng Wang, Shaoxia Wang, Zhaohui WangAbstract:The development of effective water management practices is critical for increasing winter wheat production and achieving food security and sustainable development of dryland agriculture in China. A 3-year field experiment was conducted from Sept 2007 to July 2010 at a tableland and a terrace in Loess Plateau to investigate the effects of Plastic Film combined with straw mulch on soil moisture, temperature, grain yield, and water use efficiency (WUE) of winter wheat in the drylands. The results indicated that grain yield and WUE greatly varied with precipitation and drought indexes among years, but the Plastic Film combined with straw mulch (FS) invariably increased grain yield (mean 35%) and WUE (mean 25%) with a slight increase of evapotranspiration (ET) (mean 8%) compared with conventional practices (CK). In the fallow period, the ridge-furrow framework in the FS treatment significantly increased rainwater retention in the furrow during periods of high precipitation, and consequently soil water storage was elevated during sowing. In the growing season, the FS treatment created soil conditions that were both cooler in the hot summer months and warmer in the cool winter months and thus effectively reduced soil water evaporation and retained moisture. Therefore, Plastic Film combined with straw mulch could serve as a water management procedure in the Loess Plateau. Compared with the tableland, a 35% lower mean grain yield and 33% lower mean WUE were recorded at the terrace, which was attributed to differences in soil properties. Thus, there is considerable potential for further improvement in winter wheat production and WUE at the terrace when the FS was adopted with the modification of soil properties.
Jun Wang - One of the best experts on this subject based on the ideXlab platform.
-
effects of Plastic Film residues on occurrence of phthalates and microbial activity in soils
Chemosphere, 2016Co-Authors: Jun Wang, Ying Teng, Peter Christie, Manyun Zhang, Gangcai Chen, Tongbin Zhu, Shen Zhang, Yongming LuoAbstract:Plastic Film mulching has played an important role in Chinese agriculture, especially in vegetable production, but large amounts of Film residues can accumulate in the soil. The present study investigated the effects of Plastic Film residues on the occurrence of soil PAEs and microbial activities using a batch pot experiment. PAE concentrations increased with increasing Plastic Film residues but the soil microbial carbon and nitrogen, enzyme activities and microbial diversity decreased significantly. At the end of the experiment the PAE concentrations were 0-2.02 mg kg(-1) in the different treatments. Soil microbial C and N, enzyme activities, AWCD value, and Shannon-Weaver and Simpson indices declined by about 28.9-76.2%, 14.9-59.0%, 4.9-22.7%, 23.0-42.0% and 1.8-18.7%, respectively. Soil microbial activity was positively correlated with soil PAE concentration, and soil PAE concentrations were impacted by Plastic color and residue volume. Correlations among, and molecular mechanisms of, Plastic Film residues, PAE occurrence and microbial activity require further study.
-
occurrence and risk assessment of phthalate esters paes in vegetables and soils of suburban Plastic Film greenhouses
Science of The Total Environment, 2015Co-Authors: Jun Wang, Yongming Luo, Peter Christie, Manyun Zhang, Gangcai Chen, Ying TengAbstract:Phthalate esters (PAEs) are suspected of having adverse effects on human health and have been frequently detected in soils and vegetables. The present study investigated their occurrence and composition in Plastic Film greenhouse soil-vegetable systems and assessed their potential health risks to farmers exposed to these widespread pollutants. Six priority control phthalates, namely dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP), were determined in 44 Plastic Film greenhouse vegetables and corresponding soils. Total PAEs ranged from 0.51 to 7.16mgkg(-1) in vegetables and 0.40 to 6.20mgkg(-1) in soils with average concentrations of 2.56 and 2.23mgkg(-1), respectively. DnBP, DEHP and DnOP contributed more than 90% of the total PAEs in both vegetables and soils but the proportions of DnBP and DnOP in vegetables were significantly (p 3.00mgkg(-1) but were <2.50mgkg(-1) in the corresponding soils. Stem and leaf vegetables accumulated more PAEs. There were no clear relationships between vegetable and soil PAEs. Risk assessment indicates that DnBP, DEHP and DnOP exhibited elevated non-cancer risk with values of 0.039, 0.338 and 0.038, respectively. The carcinogenic risk of DEHP was about 3.94×10(-5) to farmers working in Plastic Film greenhouses. Health risks were mainly by exposure through vegetable consumption and soil ingestion.
-
soil contamination by phthalate esters in chinese intensive vegetable production systems with different modes of use of Plastic Film
Environmental Pollution, 2013Co-Authors: Jun Wang, Yongming Luo, Ying Teng, Peter Christie, Zhengao LiAbstract:The concentrations of six priority phthalic acid esters (PAEs) in intensively managed suburban vegetable soils in Nanjing, east China, were analyzed using gas chromatography-mass spectrometry (GC-MS). The total PAE concentrations in the soils ranged widely from 0.15 to 9.68 mg kg(-1) with a median value of 1.70 mg kg(-1), and di-n-butyl phthalate (DnBP), bis-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) were the most abundant phthalate esters. Soil PAR concentrations depended on the mode of use of Plastic Film in which PAEs were incorporated as Plasticizing agents and both the Plastic Film and poultry manure appeared to be important sources of soil PAEs. Vegetables in rotation with flooded rice led to lower concentrations of PAEs in soil. The results indicate that agricultural Plastic Film can be an important source of soil PAE contamination and further research is required to fully elucidate the mechanisms of PAE contamination of intensive agricultural soils with different use modes of use of Plastic Film. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.
-
Plastic Film mulch effect on spring wheat in a semiarid region
Journal of Sustainable Agriculture, 2005Co-Authors: Jun WangAbstract:ABSTRACT The negative effect on the grain yield of spring wheat when mulching with clear Plastic Film was studied in a semiarid area. Four treatments were set up: M–Plastic Film mulching without phosphorus application; P–phosphorus supplied without mulching; MP–phos–phorus supplied and mulching; and CK–without Film mulching or phosphorus. The dry year, 1998 had only 115 mm rainfall, but a wet year, in 1999, had 240 mm rainfall for the growing periods. Root biomass was significantly enhanced in the mulched treatments, but the amount of water absorbed from the soil did not increase in corresponding proportion. Film mulching reduced biomass ratio of shoots to roots (S/R) by 52% for treatment M and 43% for treatment PM during the late growing period, and S/R was 25% lower in 1998, than in 1999 during the same period. Grain yields were significantly lower in mulched treatments, than in the non-mulched treatments in 1998.
Yongming Luo - One of the best experts on this subject based on the ideXlab platform.
-
effects of Plastic Film residues on occurrence of phthalates and microbial activity in soils
Chemosphere, 2016Co-Authors: Jun Wang, Ying Teng, Peter Christie, Manyun Zhang, Gangcai Chen, Tongbin Zhu, Shen Zhang, Yongming LuoAbstract:Plastic Film mulching has played an important role in Chinese agriculture, especially in vegetable production, but large amounts of Film residues can accumulate in the soil. The present study investigated the effects of Plastic Film residues on the occurrence of soil PAEs and microbial activities using a batch pot experiment. PAE concentrations increased with increasing Plastic Film residues but the soil microbial carbon and nitrogen, enzyme activities and microbial diversity decreased significantly. At the end of the experiment the PAE concentrations were 0-2.02 mg kg(-1) in the different treatments. Soil microbial C and N, enzyme activities, AWCD value, and Shannon-Weaver and Simpson indices declined by about 28.9-76.2%, 14.9-59.0%, 4.9-22.7%, 23.0-42.0% and 1.8-18.7%, respectively. Soil microbial activity was positively correlated with soil PAE concentration, and soil PAE concentrations were impacted by Plastic color and residue volume. Correlations among, and molecular mechanisms of, Plastic Film residues, PAE occurrence and microbial activity require further study.
-
occurrence and risk assessment of phthalate esters paes in vegetables and soils of suburban Plastic Film greenhouses
Science of The Total Environment, 2015Co-Authors: Jun Wang, Yongming Luo, Peter Christie, Manyun Zhang, Gangcai Chen, Ying TengAbstract:Phthalate esters (PAEs) are suspected of having adverse effects on human health and have been frequently detected in soils and vegetables. The present study investigated their occurrence and composition in Plastic Film greenhouse soil-vegetable systems and assessed their potential health risks to farmers exposed to these widespread pollutants. Six priority control phthalates, namely dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP), were determined in 44 Plastic Film greenhouse vegetables and corresponding soils. Total PAEs ranged from 0.51 to 7.16mgkg(-1) in vegetables and 0.40 to 6.20mgkg(-1) in soils with average concentrations of 2.56 and 2.23mgkg(-1), respectively. DnBP, DEHP and DnOP contributed more than 90% of the total PAEs in both vegetables and soils but the proportions of DnBP and DnOP in vegetables were significantly (p 3.00mgkg(-1) but were <2.50mgkg(-1) in the corresponding soils. Stem and leaf vegetables accumulated more PAEs. There were no clear relationships between vegetable and soil PAEs. Risk assessment indicates that DnBP, DEHP and DnOP exhibited elevated non-cancer risk with values of 0.039, 0.338 and 0.038, respectively. The carcinogenic risk of DEHP was about 3.94×10(-5) to farmers working in Plastic Film greenhouses. Health risks were mainly by exposure through vegetable consumption and soil ingestion.
-
soil contamination by phthalate esters in chinese intensive vegetable production systems with different modes of use of Plastic Film
Environmental Pollution, 2013Co-Authors: Jun Wang, Yongming Luo, Ying Teng, Peter Christie, Zhengao LiAbstract:The concentrations of six priority phthalic acid esters (PAEs) in intensively managed suburban vegetable soils in Nanjing, east China, were analyzed using gas chromatography-mass spectrometry (GC-MS). The total PAE concentrations in the soils ranged widely from 0.15 to 9.68 mg kg(-1) with a median value of 1.70 mg kg(-1), and di-n-butyl phthalate (DnBP), bis-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) were the most abundant phthalate esters. Soil PAR concentrations depended on the mode of use of Plastic Film in which PAEs were incorporated as Plasticizing agents and both the Plastic Film and poultry manure appeared to be important sources of soil PAEs. Vegetables in rotation with flooded rice led to lower concentrations of PAEs in soil. The results indicate that agricultural Plastic Film can be an important source of soil PAE contamination and further research is required to fully elucidate the mechanisms of PAE contamination of intensive agricultural soils with different use modes of use of Plastic Film. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.
-
Empirical estimation of pollution load and contamination levels of phthalate esters in agricultural soils from Plastic Film mulching in China
Environmental Earth Sciences, 2013Co-Authors: Yongshan Chen, Qiaoying Lin, Chunfa Wu, Youwei Hong, Haibo Zhang, Yongming LuoAbstract:Pollution load and contamination levels of phthalate esters (PAEs) in\nagricultural soils throughout China were studied in this work. The usage\namount and residual rates of Plastic Film were the main factors\nexplaining the variation among regions and leading to higher pollution\nload and contamination levels in agricultural big provinces. However,\nhigher pollution loads and contamination levels frequently occurred\nunder non-recycling than recycling scenarios during calculation.\nExtremely high loads (more than 10 kg/ha/year) of PAEs were estimated in\nfive areas including Beijing city, Tibet, Liaoning Province, Jilin\nProvince and Fujian Province and the high contamination levels in\nagricultural soil were presented in these places with more than 4.0\nmg/kg under non-recycling scenarios. The predicted concentrations of\nPAEs in soils exceed the target value for soils from Netherlands (I PAEs\npound = 0.1 mg/kg), indicating very high contamination of most Chinese\nagricultural soils. Significant differences in estimation results after\nPlastic Film utilization suggest that decreasing Plastic Film residue\nafter application is an effective measure to control PAE pollution in\nsoils. However, the comparison between contamination levels of PAEs\nestimated by the model and the previous detections of PAEs pollution\nlevels in agricultural soils showed that there were presented wide range\nof PAE sources indicated to agricultural soils.
Ying Teng - One of the best experts on this subject based on the ideXlab platform.
-
effects of Plastic Film residues on occurrence of phthalates and microbial activity in soils
Chemosphere, 2016Co-Authors: Jun Wang, Ying Teng, Peter Christie, Manyun Zhang, Gangcai Chen, Tongbin Zhu, Shen Zhang, Yongming LuoAbstract:Plastic Film mulching has played an important role in Chinese agriculture, especially in vegetable production, but large amounts of Film residues can accumulate in the soil. The present study investigated the effects of Plastic Film residues on the occurrence of soil PAEs and microbial activities using a batch pot experiment. PAE concentrations increased with increasing Plastic Film residues but the soil microbial carbon and nitrogen, enzyme activities and microbial diversity decreased significantly. At the end of the experiment the PAE concentrations were 0-2.02 mg kg(-1) in the different treatments. Soil microbial C and N, enzyme activities, AWCD value, and Shannon-Weaver and Simpson indices declined by about 28.9-76.2%, 14.9-59.0%, 4.9-22.7%, 23.0-42.0% and 1.8-18.7%, respectively. Soil microbial activity was positively correlated with soil PAE concentration, and soil PAE concentrations were impacted by Plastic color and residue volume. Correlations among, and molecular mechanisms of, Plastic Film residues, PAE occurrence and microbial activity require further study.
-
occurrence and risk assessment of phthalate esters paes in vegetables and soils of suburban Plastic Film greenhouses
Science of The Total Environment, 2015Co-Authors: Jun Wang, Yongming Luo, Peter Christie, Manyun Zhang, Gangcai Chen, Ying TengAbstract:Phthalate esters (PAEs) are suspected of having adverse effects on human health and have been frequently detected in soils and vegetables. The present study investigated their occurrence and composition in Plastic Film greenhouse soil-vegetable systems and assessed their potential health risks to farmers exposed to these widespread pollutants. Six priority control phthalates, namely dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP), were determined in 44 Plastic Film greenhouse vegetables and corresponding soils. Total PAEs ranged from 0.51 to 7.16mgkg(-1) in vegetables and 0.40 to 6.20mgkg(-1) in soils with average concentrations of 2.56 and 2.23mgkg(-1), respectively. DnBP, DEHP and DnOP contributed more than 90% of the total PAEs in both vegetables and soils but the proportions of DnBP and DnOP in vegetables were significantly (p 3.00mgkg(-1) but were <2.50mgkg(-1) in the corresponding soils. Stem and leaf vegetables accumulated more PAEs. There were no clear relationships between vegetable and soil PAEs. Risk assessment indicates that DnBP, DEHP and DnOP exhibited elevated non-cancer risk with values of 0.039, 0.338 and 0.038, respectively. The carcinogenic risk of DEHP was about 3.94×10(-5) to farmers working in Plastic Film greenhouses. Health risks were mainly by exposure through vegetable consumption and soil ingestion.
-
soil contamination by phthalate esters in chinese intensive vegetable production systems with different modes of use of Plastic Film
Environmental Pollution, 2013Co-Authors: Jun Wang, Yongming Luo, Ying Teng, Peter Christie, Zhengao LiAbstract:The concentrations of six priority phthalic acid esters (PAEs) in intensively managed suburban vegetable soils in Nanjing, east China, were analyzed using gas chromatography-mass spectrometry (GC-MS). The total PAE concentrations in the soils ranged widely from 0.15 to 9.68 mg kg(-1) with a median value of 1.70 mg kg(-1), and di-n-butyl phthalate (DnBP), bis-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) were the most abundant phthalate esters. Soil PAR concentrations depended on the mode of use of Plastic Film in which PAEs were incorporated as Plasticizing agents and both the Plastic Film and poultry manure appeared to be important sources of soil PAEs. Vegetables in rotation with flooded rice led to lower concentrations of PAEs in soil. The results indicate that agricultural Plastic Film can be an important source of soil PAE contamination and further research is required to fully elucidate the mechanisms of PAE contamination of intensive agricultural soils with different use modes of use of Plastic Film. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.