Wei Zheng

• Ph.D.
• Professor (Associate) at University of Illinois Urbana-Champaign

The co-occurrence of nutrients and pharmaceuticals and personal care products (PPCPs) in sewage effluent can degrade water quality of the receiving watersheds. This study investigated the simultaneous removal of excess nutrients and PPCP contaminants by developing a novel woodchip bioreactor and biochar (B2) treatment system. The result revealed th...

Phosphorus (P) losses from drained agricultural fields are a major cause of eutrophication. In this study, we evaluated the performance of three types of phosphorus sorbing materials (PSMs), including P polymer sorbent pellets, designer biochar pellets, and iron shavings materials, in removing dissolved P at both laboratory and field scales. The la...

Excess nutrients, such as phosphorus (P), in watersheds jeopardize water quality and trigger harmful algal blooms. Using phosphorus sorption material (PSM) to capture P from wastewater and agricultural runoff can help recover nutrients and prevent their water pollution. In this study, a novel designer biochar was generated by pyrolyzing woody bioma...

Since the establishment of the US Hypoxia Task Force (HTF) in 1997, billions of dollars have been invested in Nutrient Reduction Strategy (NRS) implementation in the Mississippi and Atchafalaya River basins (MARB) to reduce the Gulf of Mexico hypoxic zone size to less than 5,000 km2 (1,930 mi2) by 2035 (USEPA 2022). However, after 25 years of conti...

Biosolids and sewage effluent application to agricultural fields is becoming a win-win practice as both an economical waste management strategy and a source of nutrients and organic matter for plant growth. However, these organic wastes contain a variety of trace chemicals of environmental concern such as pharmaceuticals and personal care products...

Purpose of Review Land application of organic wastes such as sewage effluent, biosolids, and animal wastes can introduce pharmaceuticals and personal care products (PPCPs) into soils. Food plants grown in soils receiving organic wastes may take up PPCP contaminants and accumulate them in the edible tissues. The purpose of this review is to summariz...

Excessive phosphorus (P) in marine and freshwater systems has been identified as a primary perpetrator for the harmful and nuisance algal blooms. In this study, a novel designer biochar was produced from sawdust biomass treated with lime sludge prior to pyrolysis. The adsorption of dissolved P on the designer biochar was comprehensively evaluated u...

From the standpoint of increasing agronomic yields, it is crucial to add proper biochars to fitting soils for appropriate plant growth under suitable environmental conditions. For fertile soils, combined applications of biochar and chemical fertilizers or compost can be effective and feasible in improving plant growth and increasing crop yields. Th...

Emerging chemical contaminants such as pharmaceutical residues in water resources continues to threaten the homeostasis of our ecosystem. We have developed a ‘smart-filter’ comprised of tunable, biodegradable, and commercially-amenable pharmaceutical-nano-carbo-scavengers (PNCS) to efficiently and safely remediate pharmaceutical residues. PNCS part...

Nitrapyrin is a nitrification inhibitor that is co-applied with nitrogen fertilizer in agroecosystems. There is limited information on the fate of nitrapyrin after it is applied to agricultural soils. Over the course of one year (March 2016 to June 2017), 192 water samples from seven streams across Iowa and Illinois were analyzed for nitrapyrin, it...

Kewaunee County, Wisconsin is an agricultural area dominated by concentrated animal feeding operations and manure fertilized cropland. The objective of this study was to characterize chemical and antibiotic resistance gene (ARG) profiles of 20 surface water locations in Kewaunee County to better understand relationships between agricultural contami...

Manure-containing water (MCW) is frequently used for agricultural amendment, a practice that introduces natural and synthetic hormones to the environment. Advanced treatment processes are not practical for most animal operations, so inexpensively removing hormones from MCW by capture with vegetable oils was evaluated. Estrone (E1) and 17β-estradiol...

Pretreatment of biomass with phosphoric acid (H 3 PO 4 ) for biochar production was expected to improve carbon (C) retention, porosity structure, and the sorption ability of biochar. This study investigated the interaction of phosphorus with the C structure to elucidate the mechanisms by which H 3 PO 4 simultaneously captured C and created micropor...

Reclaimed water is increasingly used to supplement water resources. However, reclaimed water has a complex matrix, which includes emerging chemical contaminants, that is introduced to the soil when this water is used for irrigation. The effects of microbial activity, dissolved matter, nutrients, and particulate matter in reclaimed water on half-lif...

Fumigating soil is important for the production of many high-value vegetable, fruit, and tree crops, but fumigants are toxic pesticides with relatively high volatility, which can lead to significant atmospheric emissions. A field experiment was conducted to measure emissions and subsurface diffusion of a mixture of 1,3-dichloropropene (1,3-D) and c...

Two phosphate fertilizers, triple superphosphate (TSP) and bone meal (BM), were premixed with sawdust and switchgrass biomass for pyrolytic biochar formation. Carbon retention, P release kinetics, and capacity of biochar for stabilizing heavy metals in soil were evaluated. Results show that TSP and BM pretreatment increased carbon retention from 53...

Soil fumigation is an important agronomic practice in the production of many high-value vegetable and fruit crops, but the use of chemical fumigants can lead to excessive atmospheric emissions. A large-scale (2.9 ha) field experiment was conducted to obtain volatilization and cumulative emission rates for two commonly-used soil fumigants under typi...

The feedstocks for biochar production are diverse and many of them contain various minerals in addition to being rich in carbon. Twelve types of biomass classified into 2 categories: plant-based and municipal waste, were employed to produce biochars under 350°C and 500°C. Their pH, point of zero net charge (PZNC), zeta potential, cation and anion e...

There is often over 50% carbon loss during the thermal conversion of biomass into biochar, leading to it controversy for the biochar formation as a carbon sequestration strategy. Sometimes the biochar also seems not to be stable enough due to physical, chemical, and biological reactions in soils. In this study, three phosphorus-bearing materials, H...

The widespread occurrence of pharmaceuticals and personal care products (PPCPs) and natural hormones in watersheds has been recognized as an emerging environmental issue. Potential uptake and internalization of these emerging contaminants by food plants that are irrigated with contaminated water is becoming a food safety issue. In the present study...

This study investigated the distribution and evolution of organic phases during biochar formation from twelve waste biomass and at the highest heating temperatures between 200 °C and 650 °C. Relation of the organic phase transformation to the carbon loss and pore structure was also analyzed. The organic phases in both feedstock biomass and the deri...

This study presents the complete utilization of spent coffee grounds to produce biodiesel, bio-oil, and biochar. Lipids extracted from spent grounds were converted to biodiesel. The neat biodiesel and blended (B5 and B20) fuel properties were evaluated against ASTM and EN standards. Although neat biodiesel displayed high viscosity, moisture, sulfur...

Field application of livestock manure introduces animal hormones and veterinary antibiotics into the environment. Colloids present in manure may potentially intensify the environmental risk of groundwater pollution by colloid-facilitated contaminant transport. The transport behavior of the veterinary antibiotic florfenicol in saturated homogeneousl...

Wastewater from concentrated animal feeding operations (CAFOs) frequently contains high concentrations of steroid estrogenic hormones. Release of these hormones into the environment may occur when CAFO wastewater is applied to agricultural lands as a nutrient and water source for crop production. To assess the potential risk of hormone contaminants...

Soil fumigation is important for growing many fruits and vegetable crops, but fumigant emissions may contaminate the atmosphere. A large-scale field experiment was initiated to test the hypothesis that adding composted municipal green waste to the soil surface in an agricultural field would reduce atmospheric emissions of the 1,3-dichloropropene (1...

Ceftiofur is a third-generation cephalosporin antibiotic that has been widely used to treat bacterial infections in concentrated animal feeding operations (CAFOs). Land application of CAFO waste may lead to the loading of ceftiofur residues and its metabolites to the environment. To understand the potential contamination of the antibiotic in the en...

Biochar is a carbon-rich product generated from biomass through pyrolysis. This study evaluated the ability of an unmodified biochar to sorb two triazine pesticides - atrazine and simazine, and thereby explored potential environmental values of biochar on mitigating pesticide pollution in agricultural production and removing contaminants from waste...

Biochar is a carbon-rich product generated from biomass through pyrolysis. This study evaluated the ability of an unmodified biochar to sorb two triazine pesticides – atrazine and simazine, and thereby explored potential environmental values of biochar on mitigating pesticide pollution in agricultural production and removing contaminants from waste...

A field experiment was conducted to measure subsurface movement and volatilization of 1,3-dichloropropene (1,3-D) after shank injection to an agricultural soil. The goal of this study was to evaluate the effect of sprinkler irrigation on the emissions of 1,3-D to the atmosphere and is based on recent research that has shown that saturating the soil...

Concentrated animal feeding operations (CAFOs) generate large volumes of manure and manure-contaminated wash and runoff water. When applied to land at agronomic rates, CAFO wastewater has the potential to be a valuable fertilizer and soil amendment that can improve the physical condition of the soil for plant growth and reduce the demand for high q...

Pyrazosulfuron ethyl (PE) and halosulfuron methyl (HM) are two new highly active sulfonylurea herbicides that have been widely used for weed control in a variety of vegetables and other crops. These two herbicides have similar molecular structures, differing only in the substitutions on the pyrazole ring. Chemical hydrolysis is a primary process af...

The emission to the atmosphere of soil fumigants such as chloropicrin represents a potentially important human exposure pathway. Commonly, determining the air concentration of fumigants is carried out by pumping air through sorbent tubes which chemically retain the fumigant. In order to obtain an accurate measurement, it is essential that the fumig...

The environmental loading of steroid hormones contained in dairy wastes may cause an adverse effect on aquatic species. To better assess the potential risks of hormone contamination resulting from land application of dairy wastes, various steroid hormones were determined in a typical dairy waste disposal system. Quantitative methods using gas chrom...

The prevalent use of soil fumigants has resulted in air pollution in some agricultural regions. Our previous research showed that application of thiosulfate fertilizers at the soil surface may offer an effective and economical approach to reduce the emission of halogenated fumigants via a chemical remediation process. In this fumigant emission-redu...

Changes in fruit quality, decay, phenolic and anthocyanin content, and antioxidant capacity of strawberries (Fragaria × ananassa Duch. cv. Allstar) stored under air and high oxygen atmospheres at 5 °C were investigated. Freshly harvested strawberries were placed in jars and ventilated continuously with air or with 40, 60, 80, or 100 kPa O2 at 5 °C...

Metam sodium is the most widely used soil fumigant in the United States. The primary breakdown product of metam sodium in soil is methyl isothiocyanate (MITC), an active pesticidal agent with a high toxicity and a great potential for volatilization. Reducing atmospheric emissions of MITC is therefore critical to maintain air quality. The objective...

Sulfadimethoxine is a widely used sulfonamide veterinary antibiotic and could be a source of agricultural contamination. Therefore, information is needed about its degradation kinetics in manure under aerobic conditions. Based on the analysis of first-order kinetics and the assumption that sulfadimethoxine availability for degradation in manure cou...

Halogenated fumigants are among the most heavily used pesticides in agriculture. Because of their high mobility and toxicological characteristics, the contamination of air or groundwater by these compounds has been a great environmental concern. In this study, we investigated dehalogenation of several halogenated fumigants by polysulfides. The reac...

Soil fumigants are becoming an important source of volatile organic compounds (VOCs) in air, especially in some agricultural areas. In this study, we used thiourea to construct a reactive surface barrier (RSB) at the soil surface for reducing 1,3-dichloropropene (1,3-D) volatilization. The agrochemical thiourea could rapidly transform volatile 1,3-...

The chlorinated fumigants chloropicrin (trichloronitromethane) and 1,3-dichloropropene (1,3-D) are extensively used in agricultural production for the control of soilborne pests. The reaction of these two fumigants with hydrogen sulfide species (H2S and HS-) was examined in well-defined anoxic aqueous solutions. Chloropicrin underwent an extremely...

Imidacloprid, the major component of many widely used insecticide formulations, is highly persistent in soils. In this study, the sorption of imidacloprid by six soils as well as its photodegradation and hydrolysis in water were studied. The soils differed significantly in organic matter content and other physical and chemical properties. Sorption...

Halogenated fumigants have been used extensively in production agriculture to control soilborne pests. These types of pesticides are highly volatile and are prone to affect air quality and imperil public health. In the present study, a chemical tarp approach, termed a reactive surface barrier (RSB), was developed to reduce the emission of fumigant...

Metam sodium (metam) is a widely used soil fumigant. Combined application of metam and other available fumigants is intended to produce synergic pesticidal effects for a broad spectrum of pest control in soil fumigation. This study aimed to test the compatibility of metam with the halogenated fumigants 1,3-dichloropropene (1,3-D), chloropicrin, met...

The effects of preharvest methyl jasmonate (MJ) application on fruit quality, flavonoid content and antioxidant capacity in black raspberry cv. Jewel (Rubus occidentalis L) and red raspberry cv. Autumn Bliss (Rubus idaeus subsp.) were studied under field condition. Raspberries treated with MJ had higher soluble solids content, total sugars, fructos...

Propachlor and other chloroacetanilide herbicides are frequently detected contaminants of groundwater and surface water in agricultural regions. The purpose of this work was to develop a new approach to remove propachlor residues from the environment via chemical remediation by the nitrification inhibitor thiourea. The transformation processes of p...

Soil fumigation is useful for controlling soil-borne pests and diseases in high-cash-value crops. Fumigants are highly volatile, and approaches to reduce atmospheric emissions are required to protect human and environmental health. Application of fumigants through drip irrigation has been proposed as a means to decrease fumigant emissions, improve...

Methyl iodide (MeI) is a promising alternative to methyl bromide in soil fumigation. The pest-control efficacy and ground water contamination risks of MeI as a fumigant are highly related to its gas-phase distribution and leaching after soil application. In this study, the distribution and leaching of MeI in soil following shank injection and subsu...

Combining several soil fumigants to increase the broad spectrum of pest control is a common fumigation practice in current production agriculture. In this study, we investigated the effect of combined application of chloropicrin and methyl isothiocyanate (MITC) on their transformations and persistence in the environment. In aqueous solution, no dir...

Soil fumigants are used to control a wide variety of soil-borne pests in high-cash-value crops. Application of soil fumigants through drip irrigation systems is receiving increasing attention as a method to improve the uniformity of fumigant application. Little information is available on the emissions and soil distribution of fumigants following s...

Combined application of fumigants is a potential strategy to replace methyl bromide in the control of soil-borne pests. Unfortunately, abiotic and biotic interactions among fumigants restrict some combined application approaches. In this study, the kinetics and mechanisms of reaction between metam sodium (sodium methyldithiocarbamate) and the halog...

Hydrolysis is the major pathway for fumigant 1,3-dichloropropene (1,3-D) degradation in water and soil, yet the process is not well understood. Experiments were conducted to investigate the effect of various environmental factors on the rate of 1,3-D hydrolysis. Cis-, trans-1,3-D and their isomeric mixture were spiked into water and Arlington soil...

Methyl iodide (MeI) is considered a very promising fumigant alternative to methyl bromide (MeBr) for controlling soil-borne pests. Because atmospheric emission of highly volatile fumigants contributes to air pollution, feasible strategies to reduce emissions are urgently needed. In this study, thiourea (a nitrification inhibitor) was shown to accel...

The direct and sensitized photodegradations of imidacloprid, 1-(6-chloro-3-pyridinylmethyl)-N-nitro-2-imidazolidinimine, were investigated in aqueous solution and with and without various photo-sensitizers. Results of the study revealed that the intensity of lamp-house and irradiation wavelength had significant effects on the photolysis of imidaclo...

Persistent fumigant residues in soil resulting from agricultural pest-control practices may be released into water and leached to groundwater. In this study, the leaching potential of persistent soil fumigant residues was evaluated, and the effect of dissolved organic matter (DOM) and ammonium thiosulfate (ATS) amendment was investigated. A silt lo...

The influence of high oxygen concentrations on total phenolic, total anthocyanin, individual phenolic compounds, and antioxidant capacity (measured as oxygen radical absorbance capacity, ORAC) in highbush blueberry fruit (Vaccinium corymbosum L. cv. Duke) was investigated. Freshly harvested blueberries were placed in jars ventilated continuously wi...

Fumigants are used for control of nematodes, fungi, weeds, and insects in high-cash-value crops. Because of their high volatility, a large fraction of the applied mass may be volatilized from the soil surface following application. Emission reduction strategies are needed to prevent adverse human or environmental health impacts. Some emission-reduc...

The mixture of 1,3-dichloropropene (1,3-D) and chloropicrin (CP) is used as a preplant soil fumigant. In comparison with individual fumigants, application of a mixture may affect the environmental dissipation and fate of each chemical, such as emission and degradation. We investigated the degradation of CP, 1,3-D, and their mixture in fresh soils a...

Fumigants are commonly thought to be short-lived in soil, but residues have been found in soils years following application. In this study, formation and extraction of persistent soil fumigant residues were investigated. Fumigants 1,3-dichloropropene (1,3-D), chloropicrin (CP), and methyl isothiocyanate (MITC) were spiked into Arlington, Glenelg, a...

The antioxidant activity of phenolics in fruits of blueberry (Vaccinium corymbosum cv. Sierra), cranberry (Vaccinium macrocarpon cv. Ben Lear), wild chokeberry (Aronia melanocarpa), and lingonberry (Vaccinium vitis-idaea cv. Amberland) was determined in this study. The phenolic constituents and contents among the different berries varied considerab...

The fumigant methyl iodide (MeI, iodomethane) is considered a promising alternative to methyl bromide (MeBr) for soil-borne pest control in high-cash-value crops. However, the high vapor pressure of MeI results in emissions of a significant proportion of the applied mass into the ambient air, and this may lead to pollution of the environment. Integ...

Soil organic matter and clay minerals are responsible for the adsorption of many pesticides. Adsorption and competitive sorption of imidacloprid on clay minerals and humic acids (HA) were determined using the batch equilibration method. The sorption coefficient of imidacloprid on humic acids was significantly higher than that on Ca-clay minerals, i...

Cultural system [hill plasticulture (HC) versus matted row (MR)] and genotype interactions affected strawberry fruit quality. In general, fruit soluble solids content, total sugar, fructose, glucose, ascorbic acid, titratable acid, and citric acid contents were increased in the HC system. Fruit from HC also had higher flavonoid contents and antioxi...

The antioxidant capacities (oxygen radical absorbance capacity, ORAC) and total phenolic contents in extracts of 27 culinary herbs and 12 medicinal herbs were determined. The ORAC values and total phenolic contents for the medicinal herbs ranged from 1.88 to 22.30 micromol of Trolox equivalents (TE)/g of fresh weight and 0.23 to 2.85 mg of gallic a...

The influence of four day/night growing temperature combinations (18/12, 25/12, 25/22, and 30/22 °C) on phenolic acid, flavonol, and anthocyanin content and their antioxidant activities against peroxyl radicals (ROO•), superoxide radicals (O2•-), hydrogen peroxide (H2O2), hydroxyl radicals (OH•), and singlet oxygen (1O2) in fruit juice of Earliglow...

Adsorption of chloroacetanilide herbicide acetochlor, alachlor, metolachlor and propachlor on soils and soil components was determined, and the structural differences of these herbicides were used to explain the order of sorptivity. Adsorption isotherms for all herbicide-soil combinations conformed to the Freundlich equation, and Ki increased with...

The kinetics of the hydrolysis of imidacloprid were studied at different pH values and under various temperatures. Imidacloprid was found to be stable in acidic and neutral water, but readily hydrolysed in alkaline water. The main hydrolysis product was found to be 1-[(6-chloro-3-pyridinyl)methyl]-2-imidazolidone, and a mechanism for its formation...

The physical and photocatalytic properties of the TiO2 loaded on a unique silica using a TiO2 sols, which was prepared by the hydrolysis of titanium n-butoxide in water (pH=1.1) containing different alcohols and alcohol concentration, have been examined. Compared to the bare TiO2 prepared in parallel, all the supported TiO2 showed a higher photoact...

The kinetics of the hydrolysis of imidacloprid were studied at diþ erent pH values and under various temperatures. Imidacloprid was found to be stable in acidic and neutral water, but readily hydrolysed in alkaline water. The main hydrolysis product was found to be 1-[ (6-chloro-3-pyridinyl)methyl ]-2-imidazolidone, and a mechanism for its formatio...

The emission to the atmosphere of soil fumigants such as chloropicrin represents a potentially important human exposure pathway. Commonly, determining the air concentration of fumigants is carried out by pumping air through sorbent tubes which chemically retain the fumigant. In order to obtain an accurate measurement, it is essential that the fumig...

Introduction. The State regulatory agencies' current VOC inventories are based on assuming that 100% of the VOC portion of an applied pesticide is lost to the atmosphere. This tends to overestimate the VOC loading since pesticides are affected to some degree by irreversible sorption, and abiotic and biotic degradation that tends to reduce emissions...