Although pesticides have been widely used worldwide to enhance crop yield and product quality,most pesticides are harmful to the environment and human health.Plants absorb pesticides mainly from air and soil.Therefore...Although pesticides have been widely used worldwide to enhance crop yield and product quality,most pesticides are harmful to the environment and human health.Plants absorb pesticides mainly from air and soil.Therefore,the soil-plant pathway is essential for pesticide absorption.Bioconcentration factor(BCF)has extensively been applied to evaluate potential plant contamination by pesticides from soil.Hence,this study developed a simplified plant transpiration-based plant uptake model(PT-model)to estimate plant pesticides’BCF from soil based on plant transpiration.Remote sensing techniques were employed to generate spatiotemporal continuous plant transpiration via evapotranspiration.Pesticide BCF mapping was achieved by integrating PT-model with Moderate Resolution Imaging Spectroradiometer(MODIS)remotely sensed data.The results were compared with a verified model driven by relative humidity and air temperature(RA-model),which has been confirmed byfindings from previous studies.The estimated BCF was within the boundaries of the RA-model,indicating the simulation’s overall acceptability.In this study,the BCF temporal trend estimated by the proposed method agreed with the RA-model assimilating meteorology datasets,while the spatial distribution was partially inconsistent.Overall,the proposed method generates the spatiotemporal patterns of pesticide BCF with relatively consistent results supported by previous records andfindings.展开更多
Plant uptake factor （PUF）, single-variable regression of natural log-transformed concentrations in rice grain/vegetables versus natural log-transformed concentrations in soil and multiple-variable regression with so...Plant uptake factor （PUF）, single-variable regression of natural log-transformed concentrations in rice grain/vegetables versus natural log-transformed concentrations in soil and multiple-variable regression with soil concentrations and pH, was derived, validated and compared based on the paired crop and soil data collected from studies regarding As, Cd and Pb contaminated croplands in China. Results showed that the median value of PUF did not present deterministic prediction. But after natural logarithm transformation, the PUF followed Gaussian distribution which could be useful in risk assessment. The single-variable regression models were significant for As, Cd and Pb uptake both by rice and vegetables; however, the standard errors of all the regressions were comparatively large. Soil pH as a variable was generally significant but it only contributed positively to model fit for Cd uptake. After model comparison and selection, the upper 95% prediction limits of the multiple regression model for Cd uptake by rice was recommended to calculate screening value of Cd for paddy soil based on the limit for Cd concentration in rice grain.展开更多
A total of 222 surface soil samples and 40 plant samples were collected to investigate the spatial distribution and possible sources of soil heavy metals and to know the uptake and translocation of heavy metals from r...A total of 222 surface soil samples and 40 plant samples were collected to investigate the spatial distribution and possible sources of soil heavy metals and to know the uptake and translocation of heavy metals from roots to different plant parts in a representative vegetable production area in the Baguazhou Island, a suburb of Nanjing City, East China. The arithmetic mean values of total Cd, Cr,Cu, Ni, Pb, and Zn concentrations in the soils were 0.314, 133, 41.0, 58.0, 31.8, and 114 mg kg-1, respectively. All of these values were above the topsoil background values in the Nanjing area. Multivariate and geostatistical analyses showed that soil Cd contamination was derived mainly from agricultural practices. In contrast, Cu and Zn were derived mainly from soil parent materials and Pb from atmospheric deposition from highway gasoline stations. Artemisia selengensis, a locally important specialty vegetable, accumulated heavy metals primarily in the edible leaves. The general distribution of heavy metal concentrations in this plant species showed that the highest occurred in the leaves, intermediate in the stems and lowest in the roots. Cd had the highest concentration factor(root-to-soil ratio) and may pose increased health risks in the future to the local population through the consumption of contaminated vegetables.展开更多
Biochar has been shown to be an effective organic soil amendment for the in-situ immobilization of lead(Pb).Little research has been done on the effects of biochar and zeolite interactions on Pb immobilization in cont...Biochar has been shown to be an effective organic soil amendment for the in-situ immobilization of lead(Pb).Little research has been done on the effects of biochar and zeolite interactions on Pb immobilization in contaminated calcareous soils.Therefore,the aim of this study was to investigate the effects of different levels of zeolite(2%and 4%,weight:weight)and biochars(3%,weight:weight)prepared from green compost(GB),poultry manure(PB),and municipal waste(MB)on the content of Pb in spinach shoots and Pb stabilization in a greenhouse experiment conducted using a Pb-contaminated calcareous soil.Application of GB and PB significantly decreased the Pb mobility factor(MF)from 2.8%to 4.6%and the cumulative Pb release(diethylenetriamine pentaacetate(DTPA)extraction)from 16.8%to 20.1%in the calcareous soil,which were further enhanced by the combined addition of zeolite,with Pb MF reduction from 4.4%to 8.4%and cumulative Pb release reduction from 24.8%to 28.6%.The enhancement of soil Pb immobilization was attributed to the properties of the amendments,such as high pH,ash content,and phosphorus content(10.5^(-1)1.0,390-435 g kg^(-1),and 2.5-4.3 g kg^(-1),respectively).Results of the soil Pb sequential extraction and Pb release kinetics were highly and significantly correlated with spinach shoot Pb content.Soil chemical data showed that the application of MB with 4%zeolite was the most effective treatment for immobilizing Pb(8.4%reduction in Pb MF and 28.6%reduction in cumulative DTPA-extractable Pb),which is in agreement with the results of the spinach shoot Pb(89.0%reduction in Pb uptake).展开更多
In some densely-populated countries, farmland has been widely cadmium (Cd) contaminated, and the utilization of the contaminated farmland for crop production is currently unavoidable. This necessitates the use of low-...In some densely-populated countries, farmland has been widely cadmium (Cd) contaminated, and the utilization of the contaminated farmland for crop production is currently unavoidable. This necessitates the use of low-Cd crops (i.e., pollution-safe cultivars, the crop varieties with the ability to accumulate a low level of Cd in their edible parts when grown on polluted soil) in these areas and highlights the importance of knowledge on phenotypic variation in crop Cd accumulation for food Cd risk control. Studies on phenotypic variation in heavy metal accumulation started decades ago for a wide range of crops, and synthesis of the scattered experimental results in the literature is in need. We built a Low-Cd Crops Database based on literature research, and relevant meta-analysis was performed to quantitatively explore the phenotypic variation in Cd uptake and translocation of rice and wheat. Considerable variability existed among rice (median grain Cd bioconce nt ration factor (BCF) of 0.10) and wheat (median grain Cd BCF of 0.21) phenotypes in grain Cd accumulation, and this variability was labile to soil pH and the level of Cd stress. Wheat statistically had a higher root-to-shoot Cd-translocating ability than rice, highlighting potential food Cd risks and the importance of growing low-Cd wheat in slightly Cd-contaminated regions. Meanwhile, no correlations were detected among soil-to-root, root-to-shoot, and shoot-to-grain translocation factors, implying that Cd uptake and internal translocation in crops were probably controlled by different underlying gene tic mechanisms. Root-to-shoot Cd transport could be a favorable target trait for selecting and breeding low-Cd rice and wheat. In all, this review provides a comprehensive low-Cd crop list for remediation practice and a systematic meta-analysis inferring food Cd risks based on plant capacity for Cd accumulation and desired traits for low-Cd crop breeding.展开更多
基金supported by the Natural Resources of Guangdong[No.[2023]-25]National Natural Science Foundation of China[No.42171400]+1 种基金Natural Science.Foundation of Guangdong Province[No.2021A1515011324]Henan Institute of Sun Yat-sen University[No.2021-006].
文摘Although pesticides have been widely used worldwide to enhance crop yield and product quality,most pesticides are harmful to the environment and human health.Plants absorb pesticides mainly from air and soil.Therefore,the soil-plant pathway is essential for pesticide absorption.Bioconcentration factor(BCF)has extensively been applied to evaluate potential plant contamination by pesticides from soil.Hence,this study developed a simplified plant transpiration-based plant uptake model(PT-model)to estimate plant pesticides’BCF from soil based on plant transpiration.Remote sensing techniques were employed to generate spatiotemporal continuous plant transpiration via evapotranspiration.Pesticide BCF mapping was achieved by integrating PT-model with Moderate Resolution Imaging Spectroradiometer(MODIS)remotely sensed data.The results were compared with a verified model driven by relative humidity and air temperature(RA-model),which has been confirmed byfindings from previous studies.The estimated BCF was within the boundaries of the RA-model,indicating the simulation’s overall acceptability.In this study,the BCF temporal trend estimated by the proposed method agreed with the RA-model assimilating meteorology datasets,while the spatial distribution was partially inconsistent.Overall,the proposed method generates the spatiotemporal patterns of pesticide BCF with relatively consistent results supported by previous records andfindings.
基金supported by the Key Project of the National Natural Science Foundation of China (No.40432005)the Program of Knowledge Innovative Engineering of the Chinese Academy of Sciences (No.CXTD-Z2005-4)the Chinese Ministry of Science and Technology (No.2006DFA91940)
文摘Plant uptake factor （PUF）, single-variable regression of natural log-transformed concentrations in rice grain/vegetables versus natural log-transformed concentrations in soil and multiple-variable regression with soil concentrations and pH, was derived, validated and compared based on the paired crop and soil data collected from studies regarding As, Cd and Pb contaminated croplands in China. Results showed that the median value of PUF did not present deterministic prediction. But after natural logarithm transformation, the PUF followed Gaussian distribution which could be useful in risk assessment. The single-variable regression models were significant for As, Cd and Pb uptake both by rice and vegetables; however, the standard errors of all the regressions were comparatively large. Soil pH as a variable was generally significant but it only contributed positively to model fit for Cd uptake. After model comparison and selection, the upper 95% prediction limits of the multiple regression model for Cd uptake by rice was recommended to calculate screening value of Cd for paddy soil based on the limit for Cd concentration in rice grain.
基金supported by the National High Technology Research and Development Program (863 Program) of China (No. 2012AA101402-2)
文摘A total of 222 surface soil samples and 40 plant samples were collected to investigate the spatial distribution and possible sources of soil heavy metals and to know the uptake and translocation of heavy metals from roots to different plant parts in a representative vegetable production area in the Baguazhou Island, a suburb of Nanjing City, East China. The arithmetic mean values of total Cd, Cr,Cu, Ni, Pb, and Zn concentrations in the soils were 0.314, 133, 41.0, 58.0, 31.8, and 114 mg kg-1, respectively. All of these values were above the topsoil background values in the Nanjing area. Multivariate and geostatistical analyses showed that soil Cd contamination was derived mainly from agricultural practices. In contrast, Cu and Zn were derived mainly from soil parent materials and Pb from atmospheric deposition from highway gasoline stations. Artemisia selengensis, a locally important specialty vegetable, accumulated heavy metals primarily in the edible leaves. The general distribution of heavy metal concentrations in this plant species showed that the highest occurred in the leaves, intermediate in the stems and lowest in the roots. Cd had the highest concentration factor(root-to-soil ratio) and may pose increased health risks in the future to the local population through the consumption of contaminated vegetables.
文摘Biochar has been shown to be an effective organic soil amendment for the in-situ immobilization of lead(Pb).Little research has been done on the effects of biochar and zeolite interactions on Pb immobilization in contaminated calcareous soils.Therefore,the aim of this study was to investigate the effects of different levels of zeolite(2%and 4%,weight:weight)and biochars(3%,weight:weight)prepared from green compost(GB),poultry manure(PB),and municipal waste(MB)on the content of Pb in spinach shoots and Pb stabilization in a greenhouse experiment conducted using a Pb-contaminated calcareous soil.Application of GB and PB significantly decreased the Pb mobility factor(MF)from 2.8%to 4.6%and the cumulative Pb release(diethylenetriamine pentaacetate(DTPA)extraction)from 16.8%to 20.1%in the calcareous soil,which were further enhanced by the combined addition of zeolite,with Pb MF reduction from 4.4%to 8.4%and cumulative Pb release reduction from 24.8%to 28.6%.The enhancement of soil Pb immobilization was attributed to the properties of the amendments,such as high pH,ash content,and phosphorus content(10.5^(-1)1.0,390-435 g kg^(-1),and 2.5-4.3 g kg^(-1),respectively).Results of the soil Pb sequential extraction and Pb release kinetics were highly and significantly correlated with spinach shoot Pb content.Soil chemical data showed that the application of MB with 4%zeolite was the most effective treatment for immobilizing Pb(8.4%reduction in Pb MF and 28.6%reduction in cumulative DTPA-extractable Pb),which is in agreement with the results of the spinach shoot Pb(89.0%reduction in Pb uptake).
基金?nancially supported by the National Key Research and Development Program of China (No.2018YFD0800306)the Hebei Science Fund for Distinguished Young Scholars,China (No.D2018503005)
文摘In some densely-populated countries, farmland has been widely cadmium (Cd) contaminated, and the utilization of the contaminated farmland for crop production is currently unavoidable. This necessitates the use of low-Cd crops (i.e., pollution-safe cultivars, the crop varieties with the ability to accumulate a low level of Cd in their edible parts when grown on polluted soil) in these areas and highlights the importance of knowledge on phenotypic variation in crop Cd accumulation for food Cd risk control. Studies on phenotypic variation in heavy metal accumulation started decades ago for a wide range of crops, and synthesis of the scattered experimental results in the literature is in need. We built a Low-Cd Crops Database based on literature research, and relevant meta-analysis was performed to quantitatively explore the phenotypic variation in Cd uptake and translocation of rice and wheat. Considerable variability existed among rice (median grain Cd bioconce nt ration factor (BCF) of 0.10) and wheat (median grain Cd BCF of 0.21) phenotypes in grain Cd accumulation, and this variability was labile to soil pH and the level of Cd stress. Wheat statistically had a higher root-to-shoot Cd-translocating ability than rice, highlighting potential food Cd risks and the importance of growing low-Cd wheat in slightly Cd-contaminated regions. Meanwhile, no correlations were detected among soil-to-root, root-to-shoot, and shoot-to-grain translocation factors, implying that Cd uptake and internal translocation in crops were probably controlled by different underlying gene tic mechanisms. Root-to-shoot Cd transport could be a favorable target trait for selecting and breeding low-Cd rice and wheat. In all, this review provides a comprehensive low-Cd crop list for remediation practice and a systematic meta-analysis inferring food Cd risks based on plant capacity for Cd accumulation and desired traits for low-Cd crop breeding.
