scholarly journals Mobility and Phytoavailability of Arsenic and Cadmium at the Soil-corn Interface in Sewage Irrigation Polluted Farmlands Northwest, China

Author(s):  
Xiang Ning ◽  
Shengli Wang ◽  
Yi Wu ◽  
Mengbo Liu ◽  
Meng Yang ◽  
...  

Abstract The activity of heavy metals in farmland soil and the safety of food crops after long-term sewage irrigation are the premise of sustainable development of agriculture. The major pollutants of arsenic (As) and cadmium (Cd) in farmland-corn system affected by sewage irrigation for 40 years were studied. The results showed that although the content of total As in soil was high, the absorption and transport of total As by corn were relatively small, and As could not migrate down the soil profile. On the contrary, Cd mainly exists in the form of exchangeable and carbonate-bound which has strong fluidity. By optimizing the method of investigating the bioavailability of pollutants and systematically and comprehensively studying the migration law of pollutants in various parts of maize tissues, it is concluded that Cd still has high activity after stopping sewage irrigation, and the development process of maize roots has a significant relationship between the contact of heavy metals in the surface soil and the enrichment of heavy metals in the upper part of corn tissues (p < 0.01). Therefore, this study can increase the understanding of the migration law of pollutants in corn, and provide a basis for remediation of contaminated soil in local and other areas.

2018 ◽  
Vol 635 ◽  
pp. 995-1003 ◽  
Author(s):  
Ting Guo ◽  
Chenlu Lou ◽  
Weiwei Zhai ◽  
Xianjin Tang ◽  
Muhammad Z. Hashmi ◽  
...  

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Yintao Lu ◽  
Hong Yao ◽  
Dan Shan ◽  
Yichen Jiang ◽  
Shichao Zhang ◽  
...  

Soil and plant samples were collected from Tongliao, China, during the maize growth cycle between May and October 2010. Heavy metals, such as Cr, Pb, Ni, and Zn, were analyzed. The concentrations of Cr, Pb, Ni, and Zn in the wastewater-irrigated area were higher than those in the topsoil from the groundwater-irrigated area. The concentrations of metals in the maize increased as follows: Pb < Ni < Zn < Cr. In addition, Cr, Pb, and Ni mainly accumulated in the maize roots, and Zn mainly accumulated in the maize fruit. The results of translocation factors (TF) and bioconcentration factors (BCF) of maize for heavy metals revealed that maize is an excluder plant and a potential accumulator plant and can serve as an ideal slope remediation plant. In addition, the increasing heavy metal contents in soils that have been polluted by wastewater irrigation must result in the accumulation of Cr, Pb, Ni, and Zn in maize. Thus, the pollution level can be decreased by harvesting and disposing of and recovering the plant material.


2020 ◽  
Vol 66 (No. 2) ◽  
pp. 65-72 ◽  
Author(s):  
Changrui Zhou ◽  
Qiang Ma ◽  
Wantai Yu ◽  
Zhuqing Xia ◽  
Chuanchuan Ning ◽  
...  

Application of composted pig manure (PM) is a traditional practice to improve soil fertility, whereas generally leads to some environmental questions. The effects of PM application on Cd, Cu and Zn accumulation in soil and maize were investigated based on a long-term field trial in Northeast China, including control (CK), PM<sub>L</sub>, PM<sub>M</sub>, and PM<sub>H</sub>, receiving 0, 100, 250 and 500 kg total N/ha/year from 2002 to 2008 and 0, 10, 25 and 50 t fresh weight/ha/year from 2009 to 2018, respectively. Results showed that long-term soil application of PM increased maize grain yield, soil organic carbon (SOC) contents, coupled with significant accumulation and availability of Cd, Cu, and Zn in soil (0–15 cm). Compared with CK, the soil total Cd, Cu and Zn concentrations significantly increased by 105, 287 and 108% at high PM rate, respectively. Notably, the increments enhanced these heavy metals storage in maize roots rather than in grains. Moreover, the application of PM confirmed vertical transport of heavy metals in the tested soil, particularly for Cd and Cu in PM<sub>H</sub> treatment. Overall, the repeated application of PM can cause the accumulation and leaching of Cd, Cu and Zn in soil.


2015 ◽  
Vol 17 (4) ◽  
pp. 835-846 ◽  

<p>A method is proposed for the assessment of the interactive accumulation of heavy metals in soils. Sixty surface soil samples were collected from fifteen sites, at a depth of 0-30cm, evenly distributed, within the 30,700ha comprising the study area.</p> <p>It was found that at least&nbsp; some of these metals were significantly contributed to soil, i.e. Mn 9.53, Fe 8.06, Zn 0.86, Pb 0.29, Cd 0.033, Co 0.112 and Ni 0.125 kg/ha, respectively.</p> <p>Similarly considerable levels of plant nutrients were accumulated in the studied soil such as P<sub>2</sub>O<sub>5</sub> 8.6, or 3.75 kg P/ha, K<sub>2</sub>O 52.92 or 43.94 kg K/ha, and Ca 78.98 kg/ha. As expected, the heavy metals accumulated in lower concentrations than those of plant nutrients and in non toxic levels. Nevertheless, the toxicity of these metals must be considered in relation to long term accumulation.</p> <div> <p>It was shown that the proposed method, based on the quantification of the elemental interactions contribution in heavy metals, could be used as a tool for the quantitative assessment of their accumulation and for the prediction of the &laquo;silent&nbsp; pollution&raquo; that gradually occurs in soils with these metals.</p> </div> <p>&nbsp;</p>


2016 ◽  
Vol 171 ◽  
pp. 153-161 ◽  
Author(s):  
Weiqing Meng ◽  
Zuwei Wang ◽  
Beibei Hu ◽  
Zhongliang Wang ◽  
Hongyuan Li ◽  
...  

1983 ◽  
Vol 15 (5) ◽  
pp. 129-135 ◽  
Author(s):  
Z Filip ◽  
K Seidel ◽  
H Dizer

To determine whether long-term sewage treatment can take place without a pollution risk for soil and groundwater, samples from sewage irrigation fields in West Berlin which have been in use since about 1890 were analyzed for enteric viruses and microorganisms. Enteric viruses were detected in only seven samples from a total number of eighty seven taken from different soil depths. With only one exception, no viruses were found below 60 cm. No viruses were detected in groundwater samples. Long-term sewage irrigation did not result in significant changes in the colony courts of aerobic soil bacteria, but the counts of anaerobic bacteria and actinomycetes were slightly elevated and those of microscopic fungi slightly decreased. Potentially pathogenic bacteria were not detected in soil below 90 cm.


Author(s):  
Juan Carlos Moreno-Brid ◽  
Esteban Pérez Caldentey ◽  
Laura Valdez

NAFINSA was essential to Mexico’s development process. It served as the financial agent of the Federal Government and provided preferential access to long-term finance favouring selected business interests and groups. With the Washington Consensus, its tasks were reduced to correcting for market failures, becoming a complement to commercial banks, and focusing on attending the market segments falling outside the scope of commercial bank activity (notably SMEs). Although it appears as a successful story of institutional transformation, on closer inspection, NAFINSA has not been able to overcome key obstacles and its success in alleviating credit restrictions is very limited. NAFINSA must recover some of its functions, prerogatives, and responsibilities as a policy bank to become relevant in strengthening financial intermediation for capital formation.


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