[Two-stage Inhibition Effects of sp. Y4 Application on Cadmium Uptake and Transport in Wheat].

In order to evaluate the feasibility of using sp. Y4 as a cadmium （Cd）-reducing bacterial agent in contaminated wheat fields， the changes in the rhizosphere soil microbial community and Cd available state， as well as the content and transport characteristics of Cd in the wheat root， basal node， internode， and grain under the treatment of strain Y4 were tested using microbial high-throughput sequencing， step-by-step extraction， subcellular distribution， and occurrence analyses. The results showed that root application of strain Y4 significantly reduced the root and grain Cd content of wheat by 7.

[Effects of sp. Y4 on Cadmium Damage and Uptake in Rice Seedlings].

In order to investigate the effects of sp. Y4 on rice seedlings under cadmium (Cd) stress, seed germination and vermiculite culture experiments were conducted using low Cd-accumulation xiangzaoxian 24 (X24) and high Cd-accumulation Tyou 705 (T705) varieties. The effects of sp.

[Isolation and Identification of the Plant Endophyte R-13 and Its Effect on Cadmium Accumulation in L].

The combination of endophytes and hyperaccumulator plants can significantly improve the efficiency of heavy metal phytoremediation in contaminated soil. A plant endophyte named R-13 was isolated from rice roots in a cadmium (Cd) contaminated paddy field. This strain exhibited a strong tolerance to Cd and could grow on a solid medium with a Cd concentration of 300 mg·kg.

[Foliar Application of L-Cysteine: Effects on the Concentration of Cd and Mineral Elements in Rice].

To evaluate the feasibility of applying L-cysteine (L-Cys) as a foliar conditioner for Cd reduction in rice, a field experiment was conducted to investigate the concentration of Cd and mineral elements in rice after the foliar application of L-Cys. The variation in Cd distribution and morphology in key rice organs was examined to study the Cd reduction mechanisms of spraying L-Cys on rice. The results showed that foliar application of L-Cys at the rice-flowering stage significantly decreased Cd concentration in grains, in a concentration dependent manner, without inhibiting the accumulation of mineral elements Ca, Mg, K, Mn, and Zn.

[Mechanism of -allyl-L-cysteine Alleviating Cadmium Stress in Seedling Roots and Buds of Rice Seedlings].

Cd has toxic effects on rice seed germination and plant growth, which may eventually lead to decreased yield and excessive Cd content in rice grains. The potential mechanism of -allyl-L-cysteine (SAC), a natural sulfur compound derived from garlic extract, in alleviating Cd stress in young roots and buds of rice seedlings was studied by a seed germination experiment. "Zhong zao 35", one of the main rice varieties in Southern China, was selected as the test material.

[Effects of Foliar Spraying of 2,3-dimercaptosuccinic Acid on Cadmium Uptake, Transport, and Antioxidant System in Rice Seedlings].

Rice contaminated by Cd has aroused widespread public concern. It is of great importance to find effective ways to reduce Cd translocation from roots to shoots and alleviate Cd stress in rice to ensuring food quality and safety. In this study, 2,3-dimercaptosuccinic acid (DMSA) was sprayed onto the leaves of rice seedlings to evaluate the feasibility of DMSA reducing Cd translocation to rice shoots and alleviating Cd stress.

Rice vegetative organs alleviate cadmium toxicity by altering the chemical forms of cadmium and increasing the ratio of calcium to manganese.

Altering Cd chemical form is one of the mechanisms to alleviate Cd toxicity in rice plant. Field experiments were carried out in this study to investigate the potential of rice vegetative organs in altering Cd into insoluble chemical forms in the natural environment. Experimental results showed that more than 80% of Cd in rice roots existed in the insoluble forms.

[Stabilization and long-term effect of chromium contaminated soil].

Short-term (3 d and 28 d) and long-term (1 a) stabilization effects of Cr contaminated soil were investigated through nature curing, using four amendments including ferrous sulfide, ferrous sulfate, zero-valent iron and sodium dithionite. The results indicated that ferrous sulfide and zero-valent iron were not helpful for the stabilization of Cr(VI) when directly used because of their poor solubility and immobility. Ferrous sulfate could effectively and rapidly decrease total leaching Cr and Cr(VI) content.

Effects of electrokinetic treatment of contaminated sludge on migration and transformation of Cd, Ni and Zn in various bonding states.

This study assesses the effect of electrokinetic processes on the migration and bonding states of various heavy metals in municipal sludge. The transformation and migration are discussed through the examination of sludge characteristics and distribution of Cd, Zn and Ni after electrokinetic treatments. The migration and distribution of the contaminants after the electrokinetic treatments were determined for each sludge sample by sequential extraction.

[Predicting the cadmium bioavailability in the soil of sugarcane field based on the diffusive gradients in thin films with binding phase of sodium polyacrylate].

The diffusive gradients in thin films (DGT) technique with solid-state binding phases has been widely used for in situ collection and measurement of available heavy metals in waters, soils or sediments, whereas DGT with liquid binding phase is primarily used in the in situ analysis of heavy metals in waters. In this paper, rhizosphere soils of sugarcane were collected in Guangxi and the concentrations of cadmium (Cd) were determined by DGT with a solid-state binding phase of chelex100 (chelex100-DGT) and modified DGT with a liquid binding phase of sodium polyacrylate (CDM-PAAS-DGT). The result showed that the Cd contents in soils measured by DGT with both binding phases and Cd in the roots, leaves and unpolished stems of sugarcane had significant positive correlation.

[Remediation of chromium (VI) contaminated soils using permeable reactive composite electrodes technology].

Electrokinetic transport processes have been shown to have potential for the effective removal of heavy metals from soils. However, pH changes near the anode and cathode limit their widespread application in the remediation of contaminated soils. Permeable reactive composite electrodes (PRCE) were made by attaching reactive materials such as Fe(0) and zeolite to the electrodes, and the effects of the composite electrodes on pH control, chromium removal efficiency and Cr speciation changes were studied in the electrokinetic remediation process of Cr( VI) contaminated soil.

[Stabilization of heavy metals in sewage sludge by using a ferrous iron].

The stabilization of heavy metals in sewage sludge using a ferrous iron is investigated through leaching test and fractionation analysis. The results showed that FeSO4 x 7H2O was not helpful to stabilize the heavy metals in the sludge when used individually since it reduced the pH value of sludge. The pH value dropped significantly from 6.

[Application of Pb stable isotope in source identification of soil pollutants].

Stable isotopes are key importance for tracing the source of heavy metals in soils. 11 surface soil samples were collected in a contaminated site according to geostatistical results, which had a series of concentrations from almost background value of Pb to more than 2 000 microg x g(-1). Pb stable isotope composition of the soil samples was analyzed to imply the sources.

[Application of robust estimator in source identification of soil pollutants: a case study at a heavy metal contaminated site].

Spatial outliers can give us useful information on locations of pollution sources. A Genton's estimator based variogram was applied to analyse the concentration of Cu, Zn, Pb, Cd, As, Se and Hg in soils at a contaminated site. Spatial outliers were identified to imply the location of the pollution sources of heavy metals.