[Effects of Mercury Pollution on Soil Organic Carbon Stability and Carbon-fixing Microbial Communities].

To elucidate the effects of Hg pollution on soil organic carbon stability and autotrophic microbial carbon assimilation, the characteristics of soil CO emission rate, organic carbon components, and and functional microorganisms before and after 29 d of Hg pollution were studied using indoor culture experiments and molecular biology techniques. The results showed that the effects of different levels of Hg pollution on soil CO emission rates were different. High levels of Hg （S2,S3,and S5） inhibited soil CO cumulative emissions, whereas low levels of Hg （S1,S4,and S6） promoted soil carbon emissions.

[Effects of Different Fertilization Treatments on Bacterial Community and Citrus Quality in Yellow Soils of the Yunnan-Guizhou Plateau].

To investigate the intrinsic driving mechanism of citrus yield and quality enhancement under different fertilizer applications, a field experiment was conducted to study the effects of biochar （SW）, organic fertilizer （YJ）, farmyard manure （NJ）, chemical fertilizer （HF）, and no fertilizer as the control （CK） on soil physical and chemical properties, bacterial community characteristics, and citrus quality of citrus orchards in the yellow soil area of the Yunnan-Guizhou Plateau. The results showed that compared with those in the CK treatment, the yield, single fruit weight, edible rate, juice rate, vitamin C content, and soluble solids of citrus increased under the different fertilization treatments. In contrast, the titratable acid content of citrus decreased, resulting in an increase in the solid-acid ratio of citrus.

[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.

[Response Characteristics of Soil Fungal Community Structure to Long-term Continuous Cropping of Pepper].

This study aimed to clarify the effect of long-term continuous cropping of pepper on soil fungal community structure, reveal the mechanism of continuous cropping obstacles, and provide a theoretical basis for the ecological safety and sustainable development of pepper industry. We took the pepper continuous cropping soil in the vegetable greenhouse planting base of Tongren City as the research object. The diversity and community structure of fungi in farmland soil were analyzed using Illumina MiSeq high-throughput sequencing, the responses of soil physio-chemical properties and fungal community characteristics to long-term continuous pepper cropping were discussed, and the relationships between the characteristics of fungal community structure and environmental factors were determined using CCA and correlation network analysis.

[Effects of Nano-copper Oxide on Physiobiochemical Properties of L. and Its Heavy Metal Accumulation Under Cadmium Stress].

To investigate the effects of nano-copper oxide (CuO NPs) on plant growth, physio-biochemical characteristics, and heavy metal content under cadmium stress, a hydroponics experiment was conducted on the effects of single and combined treatments of CuO NPs (0, 10, 20, and 50 mg·L) and Cd (0, 1, and 5 μmol·L) on the fresh weight, photosynthetic pigment content, MDA content, antioxidant enzyme activity (CAT, POD, SOD, and GR), and Cu and Cd contents in L. The results showed that under the single addition of CuO NPs, the fresh weight and activities of CAT, POD, and GR were inhibited as a whole. Photosynthetic pigment content and SOD activity increased first and then decreased with the increase in CuO NPs concentration, whereas MDA content in leaves and roots, and Cu content in subcells of L.

[Pollution Characteristics, Source Analysis, and Risk Assessment of Heavy Metals in the Surrounding Farmlands of Manganese Mining Area].

In order to understand the status of heavy metal pollution and the resulting ecological risk of farmland soil surrounding the manganese mining area, 174 soil samples were collected, and the heavy metals(Cu, Zn, Pb, Cr, Ni, Mn, As, and Hg) were analyzed. Principal component analysis (PCA) and the positive matrix factorization (PMF) model were used to determine the source of heavy metals in the soils. The single-factor pollution index method, geo-accumulation index method, potential ecological risk assessment method, and US EPA health risk assessment model were used to evaluate the ecological environment risk of heavy metals.

[Characteristics of Microbial Community Structure in the Surrounding Farmlands of a Mercury Mining Area and Its Environmental Driving Factors].

In order to investigate the characteristics of soil microbial community structure and their relationships with environmental factors in the surrounding farmlands of a mercury mining region, we analyzed soil physical and chemical properties, Hg pollution, enzyme activity, and microbial community structure characteristics in the surrounding farmlands of a mercury mining region in Tong Ren (Bahuang Town, Bijiang District; Huaqiao Town, Shiqian County; Kaide Town, Jiangkou County; and Chuantong town, Bijiang District; referred to as BJ, SQ, JK, and TR, respectively). The relationships between the characteristics of soil microbial community structure and environmental factors were determined using redundancy analysis (RDA) and correlation network analysis. The results showed that the degree of soil Hg contamination varied depending on the sampling locations in the study region.

[Structural Characteristics of Micro-nano Particle Size Biochar and Its Adsorption Mechanism for Cd].

The aim of this study was to investigate the structural characteristics of biochar with different micro/nano particle sizes and its effect on the adsorption performance of Cd. Corn stalk biochar with different particle sizes (180-250 μm, 50-75 μm, and ≤ 20 μm, denoted as BC-1, BC-2, and BC-3, respectively) were prepared using the sieving and ball milling method. The structural properties of different particle sizes of biochar were analyzed via elemental analysis, laser particle size analysis, SEM, BET, FTIR, and XPS.

[Variations in Cadmium Accumulation and Transport and Ionomic Traits Among Different Winter Wheat Varieties].

A field trial was conducted to identify the key factors affecting intraspecific variation in the cadmium (Cd) content in the grain of winter wheat. Three wheat cultivars with low Cd accumulation and two wheat cultivars with high Cd accumulation were planted. The Cd accumulation and transport and ionomic traits were examined in different organs of the tested wheat cultivars.

[Effects of Intercropping of L. and L. on the Growth and Cadmium Accumulation of Plants].

A pot experiment was conducted to reveal the effects of intercropping a low-cadmium (Cd) accumulating cultivar and a Cd hyperaccumulator on the safe utilization and phytoextraction of Cd-polluted soils. Two cultivars of L. (the low-Cd accumulating cultivar Huajun, and the common cultivar Hanlü), were intercropped with four cultivars of L.

[Effect of Mn-Modified Biochar on the Characteristics of Aggregate Structure and the Content of Cd in Weakly Alkaline Cd-Contaminated Soil].

Field experiments were conducted to investigate the effects of Mn-based modified rice husk biochar on soil organic carbon, aggregate structure, mass load, and the content of available Cd in aggregates. The results showed that the concentration of soil organic carbon increased gradually with additional modified biochar, resulting in a 3.2%-32% increase compared with the CK.

[Effect of Different Passivating Agents on the Stabilization of Heavy Metals in Chicken Manure Compost and Its Maturity Evaluating Indexes].

We explore the effects of different passivating agents on livestock manure treatment by using chicken manure and straw as raw materials and thermophilic rapid fermentation. We investigate the effects of sepiolite (SE), calcium magnesium phosphate fertilizer (NP), biochar (BI), compounds of sepiolite plus calcium magnesium phosphate fertilizer (S+N), sepiolite plus biochar (S+B), calcium magnesium phosphate fertilizer plus biochar (N+B), and sepiolite plus calcium magnesium phosphate fertilizer and biochar (SNB) on the physical and chemical characteristics, heavy metal fraction and distribution, and organic matter content in chicken manure compost. The results showed that the addition of different passivating agents significantly increased the pH in chicken manure organic fertilizer (<0.

[Substructure Characteristics of Combined Acid-Base Modified Sepiolite and Its Adsorption for Cd(Ⅱ)].

To enhance the adsorption capacity of sepiolite (Sep) on Cd in solution, an acid-base Sep (ABsep) was obtained using the method of combined acid-base modification. The structural properties of Sep and ABsep were analyzed by adsorption-desorption isotherms of N, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray powder diffraction (XRD). Static adsorption experiments were carried out to evaluate the effects of time, mass ratio of ABsep/Cd, temperature, adsorbent dose, pH, and co-existing ions on the adsorption of Cd by ABsep.

[Characteristics of Heavy Metals in Chicken Manure Organic Fertilizers in the Huang-Huai-Hai Region and related Environmental Risk Assessment].

One hundred and twenty types of chicken manure organic fertilizer samples were collected from five provinces and two cities in the Huang-Huai-Hai region, to investigate heavy metal content, fractionation, and environmental risk through toxicity characteristic leaching procedures. Results showed that content of heavy metals in chicken manure organic fertilizer varied greatly, in the order of Zn > Cu > Pb > As > Cd. When compared with the standard for organic manure, ratios of Cd, As, and Pb exceeded the standard by 6.

[Effect of Foliar Zinc Application on Bioaccessibility of Cadmium and Zinc in Pakchoi].

Two cultivars of pakchoi with different cadmium (Cd) accumulation were grown in nutrient solutions containing low and sufficient zinc (Zn) levels. ZnSO and ZnNa EDTA were applied as foliar fertilizers. The bioaccessibilities of Cd and Zn in pakchoi were assessed by the digestion method, and the bioaccessible established daily intakes (BEDI) of Cd and Zn from pakchoi were calculated.

[Immobilization remediation of Cd and Pb contaminated soil: remediation potential and soil environmental quality].

A pot experiment was conducted to investigate the immobilization remediation effects of sepiolite on soils artificially combined contamination by Cd and Pb using a set of various pH and speciation of Cd and Pb in soil, heavy metal concentration in Oryza sativa L., and soil enzyme activity and microbial quantity. Results showed that the addition of sepiolite increased the soil pH, and the exchangeable fraction of heavy metals was converted into Fe-Mn oxide, organic and residual forms, the concentration of exchangeable form of Cd and Pb reduced by 1.

[Adsorption of Cd2+ on biochar from aqueous solution].

Biomass-based materials such as biochar have a good performance in heavy metal adsorption. The adsorption of Cd2+ on biochar converted from cotton straw was studied. Adsorption isotherm, kinetics and effect factors such as temperature, pH and ionic strength were investigated.

[Characteristics of cadmium tolerance and bioaccumulation of Bidens pilosa L. seedlings].

Bidens pilosa L. has been identified as a newly found Cd-hyperaccumulator. In the present study, the characteristics of its Cd tolerance (growth response and physiological and biochemical characteristics) and accumulation were examined.

Joint effects of arsenic and cadmium on plant growth and metal bioaccumulation: a potential Cd-hyperaccumulator and As-excluder Bidens pilosa L.

Joint effects of arsenic (As) and cadmium (Cd) on the growth of Bidens pilosa L. and its uptake and accumulation of As and Cd were investigated using the field pot-culture experiment. The results showed that single Cd ( View Article and Find Full Text PDF