The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to...The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to its rich mineral and geothermal resources.This review provides a comprehensive analysis of As content,focusing on its distribution,environmental migration,and transformation behavior across the plateau.The review further evaluates the distribution of As in different functional areas,revealing that geothermal fields(107.2 mg/kg),mining areas(53.8 mg/kg),and croplands(39.3 mg/kg)have the highest As concentrations,followed by river and lake sediments and adjacent areas(33.1 mg/kg).These elevated levels are primarily attributed to the presence of As-rich minerals,such as arsenopyrite and pyrite.Additionally,human activities,including mining and geothermal energy production,exacerbate the release of As into the environment.The review also highlights the role of localmicroorganisms,particularly those fromthe phyla Proteobacteria and Actinobacteria,which possess As metabolic genes that facilitate As translocation.Given the unique climatic conditions of the plateau,conventionalmethods for As controlmay not be fully effective.However,the review identifies promising remediation strategies that are environmentally adaptable,such as the use of local microorganisms,specific adsorbents,and integrated technologies,which offer potential solutions for managing and utilizing Ascontaminated soils on the plateau.展开更多
Achieving sustainable energy and chemical production has become an important issue for human society.Photocatalysis has attracted much attention due to its ability to harness solar energy to drive chemical reactions.M...Achieving sustainable energy and chemical production has become an important issue for human society.Photocatalysis has attracted much attention due to its ability to harness solar energy to drive chemical reactions.Metal sulfide-based photocatalysts(e.g.,Cd S,Zn In2S4)have shown substantial potential in biomass-based hydroxyl compound valorization.In this review,we summarize the recent progress in metal sulfide-based photocatalysts for the photo upgrading of biomass-derived hydroxyl compounds coupled with reduction reactions(e.g.,CO_(2)reduction,H_(2)O_(2)generation,and H_(2)evolution).The mechanism of biomass redox reactions is discussed,highlighting the potential of realizing the valorization of biomass-derived compounds coupled with the reduction reactions,which is beneficial for researchers to actively explore biomass biorefinery pathways in order to modulate the selectivity of the valueadded products.Various modification strategies are presented,including elemental doping,defect engineering,heterojunction construction,and cocatalyst loading.These strategies modulate the energy band structure,surface electron density,and built-in electric field strength of metal sulfide-based photocatalysts,thereby enhancing their photocatalytic performance.The challenges and prospects of metal sulfidebased photocatalysts in biomass valorization are analyzed.This approach contributes to the development of photocatalysts that can accelerate biomass photo-upgrading coupling reactions.This review aims to provide deeper insights into the photocatalytic biorefinery pathways and contribute to the development of functionalized photocatalysts that can accelerate biomass photo upgrading,highlighting the synergistic effects of multiple coupling reactions.展开更多
The exponential growth of antibiotic-resistant bacteria and antibiotic-resistant genes(ARGs)in soil-crop systems in recent years has posed a great challenge to ecological security and human health.While many studies h...The exponential growth of antibiotic-resistant bacteria and antibiotic-resistant genes(ARGs)in soil-crop systems in recent years has posed a great challenge to ecological security and human health.While many studies have documented the residues of ARGs in soils and crops,but little is known about who drives the proliferation of ARGs in farming systems and what their underlying mechanisms are.Herein,we explored the occurrence and proliferating behavior of ARGs in soil-crop environments in terms of root secretions and plant volatiles.This review highlighted that plant root secretions and volatile organic compounds(VOCs)served as key substances mediating the development of antibiotic resistance in the soil-crop system.Still,there is controversy here as to plant root secretions promote the ARGs proliferation or inhibit.Some studies indicated that root secretions can suppress the colonization of ARGs,mainly attributed by the production of bluntedmetabolic enzymes and blocking of cellular exocytosis systems.Whereas the others have evidenced that root secretions can promote ARGs proliferation,primarily by altering the structure of microbial communities to influence species interactions and thus indirectly affect the proliferation of ARGs.Also,VOCs can act as molecular signals to convey antibiotic resistance information to their neighbors,which in turn drive the up-regulation of ARGs expression.Even so,the mechanism by which VOC-driven antibiotic resistance acquisition and proliferation need to be further probed.Overall,this review contributed to the development of products and technologies to impede the ARGs proliferation in agricultural environment.展开更多
Formamide condensation with Ni can generate the N–C structure,widely recognized as an efficient catalyst for electrocatalytic CO_(2) reduction reaction(CO_(2)RR).To improve the utilization efficiency of Ni atoms,we i...Formamide condensation with Ni can generate the N–C structure,widely recognized as an efficient catalyst for electrocatalytic CO_(2) reduction reaction(CO_(2)RR).To improve the utilization efficiency of Ni atoms,we introduced metal oxides as substrates to modulate the growth of a formamide-Ni(FA-Ni)condensate.FA-Ni@TiO_(2) demonstrated 2.8 times higher partial CO current density and Ni turnover frequency than FA-Ni,which were also higher than those of other FA-Ni@metal oxides,including ZrO_(2),Al_(2)O_(3),Fe_(2)O_(3),and ZnO.The improved performance of CO_(2)RR can be attributed to the Ni content exposed on FA-Ni@TiO_(2) being twice that of the raw FA-Ni condensate.The Fourier transform infrared results suggested that formamide was adsorbed on TiO_(2) via the-CHO group,exposing-NH_(2) for potential interaction with Ni.As a result,Ni atoms were predispersed on the TiO_(2) surface.By contrast,the dispersion of Ni atoms was not enhanced by other metal oxides,such as Al_(2)O_(3),Fe_(2)O_(3),and ZnO,owing to the robust acidity of their surface sites.These metal oxides adsorbed formamide via-NH_(2),leading to the absence of extra-NH_(2) available for binding to Ni atoms.This study provides new insights into the development of appropriate substrates for single-atom catalysts.展开更多
The removal of highly toxic arsenic(As)and antimony(Sb)contaminants in water by adsorption presents a great challenge worldwide.Conventional adsorbents exhibit insufficient efficacy for removing pentavalent oxyanions,...The removal of highly toxic arsenic(As)and antimony(Sb)contaminants in water by adsorption presents a great challenge worldwide.Conventional adsorbents exhibit insufficient efficacy for removing pentavalent oxyanions,As(Ⅴ)and Sb(Ⅴ),which are predominant compared with the trivalent species,As(Ⅲ)and Sb(Ⅲ),in surface waters.Here,we synthesized a novel composite adsorbent,amine-functionalized polystyrene resin loaded with nano TiO_(2)(Am PSd-Ti).The mm-scale spheres showed outstanding adsorption capacities for As(Ⅲ),As(Ⅴ),Sb(Ⅲ),and Sb(Ⅴ)at 73.85,153.29,86.80,and 123.71 mg/g,respectively.Am PSd-Ti exhibited selective adsorption for As and Sb in the presence of Cl^(-),NO_(3)^(-),SO_(4)^(2-),and F^(-).As and Sb were adsorbed by the nano-sized TiO_(2)confined in the porous resin via forming innersphere complexes.The protonated amine groups enhanced the adsorption of As(Ⅴ)and Sb(Ⅴ)by electrostatic attraction and hydrogen bonding,which was confirmed by experimental results and molecular dynamics simulations.Fixed-bed column tests showed breakthrough curves with adsorption capacities of1.38 mg/g(6600 BV)and 6.65 mg/g(1260 BV)upon treating real As-contaminated groundwater and Sbcontaminated industrial wastewater.Our study highlights a feasible strategy by incorporating inorganic metal oxides into organic polymers to achieve highly efficient removal of As and Sb in real-world scenarios.展开更多
In recent years,ozone has become one of the key pollutants affecting the urban air qual-ity.Direct catalytic decomposition of ozone emerges as an effective method for ozone re-moval.Field experimentswere conducted to ...In recent years,ozone has become one of the key pollutants affecting the urban air qual-ity.Direct catalytic decomposition of ozone emerges as an effective method for ozone re-moval.Field experimentswere conducted to evaluate the effectiveness of exteriorwall coat-ings with ozone decomposition catalysts for ozone removal in practical applications.ANSYS 2020R1 software was first used for simulation and analysis of ozone concentration and flow fields to investigate the decomposition boundary of these wall coatings.The results show that the exterior wall coatings with manganese-based catalysts can effectively reduce the ozone concentration near the wall coating.The ozone decomposition efficiency is nega-tively correlated with the distance fromthe coating and the decomposition boundary range is around 18 m.The decomposition boundary will increase with the increase of tempera-ture,and decrease with the increase of the wind speed and the relative humidity.These results underscore the viability of using exterior wall coatings with catalysts for controlling ozone pollution in atmospheric environments.This approach presents a promising avenue for addressing ozone pollution through self-purifying materials on building external wall.展开更多
Heavy metal contamination of agricultural soils poses risks and hazards to humans. The remediation of heavy metal-polluted soils has become a hot topic in environmental science and engineering. In this review, the app...Heavy metal contamination of agricultural soils poses risks and hazards to humans. The remediation of heavy metal-polluted soils has become a hot topic in environmental science and engineering. In this review, the application of clay minerals for the remediation of heavy metal-polluted agricultural soils is summarized, in terms of their remediation effects and mechanisms, influencing factors, and future focus. Typical clay minerals, natural sepiolite, palygorskite, and bentonite, have been widely utilized for the in-situ immobilization of heavy metals in soils, especially Cd-polluted paddy soils and wastewater-irrigated farmland soils. Clay minerals are able to increase soil pH, decrease the chemical-extractable fractions and bioavailability of heavy metals in soils, and reduce the heavy metal contents in edible parts of plants. The immobilization effects have been confirmed in field-scale demonstrations and pot trials. Clay minerals can improve the environmental quality of soils and alleviate the hazards of heavy metals to plants. As main factors affecting the immobilization effects, the pH and water condition of soils have drawn academic attention. The remediation mechanisms mainly include liming, precipitation, and sorption effects. However, the molecular mechanisms of microscopic immobilization are unclear. F^ture studies should focus on the long-term stability and improvement of clay minerals in order to obtain a better remediation effect.展开更多
Phytoremediation is a cost-effective and environment-friendly strategy for decontaminating heavy-metal-contaminated soil.However, the practical use of phytoremediation is constrained by the low biomass of plants and l...Phytoremediation is a cost-effective and environment-friendly strategy for decontaminating heavy-metal-contaminated soil.However, the practical use of phytoremediation is constrained by the low biomass of plants and low bioavailability of heavy metals in soil.A pot experiment was conducted to investigate the effects of the metal chelator ethylenediaminetetraacetic acid(EDTA) and EDTA in combination with plant growth-promoting rhizobacteria(Burkholderia sp.D54 or Burkholderia sp.D416) on the growth and metal uptake of the hyperaccumulator Sedum alfredii Hance.According to the results, EDTA application decreased shoot and root biomass by 50% and 43%, respectively.The soil respiration and Cd,Pb, Zn uptake were depressed, while the photosynthetic rate, glutathione and phytochelatin(PC) contents were increased by EDTA application.Interestingly, Burkholderia sp.D54 and Burkholderia sp.D416 inoculation significantly relieved the inhibitory effects of EDTA on plant growth and soil respiration.Compared with the control, EDTA + D416 treatment increased the Cd concentration in shoots and decreased the Pb concentration in shoots and roots, but did not change the Zn concentration in S.alfredii plants.Furthermore,EDTA, EDTA + D54 and EDTA + D416 application increased the cysteine and PC contents in S.alfredii(p < 0.05);among all tested PCs, the most abundant species was PC2, and compared with the control, the PC2 content was increased by 371.0%, 1158.6% and 815.6%,respectively.These results will provide some insights into the practical use of EDTA and PGPR in the phytoremediation of heavy-metal-contaminated soil by S.alfredii.展开更多
Sequential extraction procedure was applied to assess the dynamics of solid-phase transformation of added Cu, Pb, Cd, and Hg in a typical Chinese paddy soil incubated under three moisture regimes (75% field capacity,...Sequential extraction procedure was applied to assess the dynamics of solid-phase transformation of added Cu, Pb, Cd, and Hg in a typical Chinese paddy soil incubated under three moisture regimes (75% field capacity, wetting-drying cycle, and flooding). The heavy metals spiked in the soil were time-dependently transferred from the easily extractable fraction (the exchangeable fraction) into less labile fractions (Fe-Mn oxide- and organic matter-bound fractions), and thus reduced lability of the metals. No significant changes were found for the carbonate-bound and residual fractions of the heavy metals in the soil during the whole incubation. Change rate of the mobility factor (MF), a proportion of weakly bound fractions (exchangeable and carbonate-bound) in the total metal of soil, reflected the transformation rate of metal speciation from the labile fractions toward stable fractions. It was found that soil moisture regime did not change the direction and pathways of transformation of metal speciation, but it significantly affected the transformation rate. In general, the paddy soil under flooding regime had higher metal reactivity compared with 75% field capacity and wetting-drying cycle regimes, resulting in the more complete movement of metals toward stable fractions. This might be related to the increased pH, precipitation of the metals with sulfides and higher concentration of amorphous Fe oxides under submerged condition.展开更多
The pollution of soils by heavy metals has dramatically increased in recent decades. Phytoextraction is a technology that extracts elements from polluted soils using hyperaccumulator plants. The selection of appropria...The pollution of soils by heavy metals has dramatically increased in recent decades. Phytoextraction is a technology that extracts elements from polluted soils using hyperaccumulator plants. The selection of appropriate plant materials is an important factor for successful phytoextraction in field. A field study was conducted to compare the efficiency of six high-biomass forage species in their phytoextraction of heavy metals(Cd, Pb, and Zn) from contaminated soil under two harvesting strategies(double harvesting or single harvesting). Among the tested plants, amaranth accumulated the greatest amounts of Cd and Zn, whereas Rumex K^(-1) had the highest amount of Pb in the shoot under both double and single harvesting. Furthermore, double harvesting significantly increased the shoot biomass of amaranth, sweet sorghum and sudangrass and resulted in higher heavy metal contents in the shoot. Under double harvesting, the total amounts of extracted Cd, Pb and Zn(i.e., in the first plus second crops) for amaranth were 945, 2 650 and 12 400 g ha^(-1), respectively, the highest recorded among the six plant species. The present results indicate that amaranth has great potential for the phytoextraction of Cd from contaminated soils. In addition, the double harvesting method is likely to increase phytoextraction efficiency in practice.展开更多
Zero-valent iron amended biochar(ZVIB)has been proposed as a promising material in immobilizing heavy metals in paddy fields.In this study,the impacts of p H of ZVIB(p H 6.3 and p H 9.7)and watering management techniq...Zero-valent iron amended biochar(ZVIB)has been proposed as a promising material in immobilizing heavy metals in paddy fields.In this study,the impacts of p H of ZVIB(p H 6.3 and p H 9.7)and watering management techniques(watering amount in the order of CON(control,5/72)>3/72>1-3/72>3/100>1/72,with 5/72,for example,representing irrigation given to 5 cm above soil surface in 72 hr regular interval)on As and Cd bioavailability for rice and its grain yield(Yield BR)were investigated in a pot experiment.Brown rice As(As BR)content was irrelative to the watering treatments,while significantly decreased(>50%)with the addition of both ZVIB materials.The diminutions of brown rice Cd(Cd BR)content as well as the Yield BR were highly dependent on both the soil amendment materials’p H and watering amount.Among all the watering treatments,3/72 treatment(15%less irrigation water than the CON)with ZVIB 6.3 amendment was the optimum fit for simultaneous reduction of As BR(50%)and Cd BR contents(19%)as well as for significant increment(12%)of the Yield BR.Although high pH(9.7)ZVIB application could also efficiently decrease As and Cd contents in brown rice,it might risk grain yield lost if appropriate(e.g.3/72 in our study)watering management technique was not chosen.Therefore,ZVIB would be an environmentally friendly option as an amendment material with proper selection of watering management technique to utilize As and Cd co-contaminated arable soils safely for paddy cultivation.展开更多
Soils in part of rice production areas have been seriously contaminated by cadmium (Cd). Rice with high Cd content over allowable limit produced in these areas is widely concerned. Low accumulation varieties can rem...Soils in part of rice production areas have been seriously contaminated by cadmium (Cd). Rice with high Cd content over allowable limit produced in these areas is widely concerned. Low accumulation varieties can remarkably decrease the Cd content in rice as well as the risk of food safety. The translocation of Cd either from soil to root system or from roots to aboveground parts is identified by a lot of ion transport proteins. Transport efficiency of Cd in some rice varieties is regulated by special metal ionic transporters. However, most varieties transport Cd by cation transporters or universal ionic transporters. Both the expression levels and time of gens controlling ionic transporters directly influence the Cd transport rates inside rice plant and the accumulation amount in different organs. Screening and utilizing specific Cd transport genes are the genetic basis of breeding low accumulation varieties.展开更多
Nutrient addition can affect the structure and diversity of grassland plant communities, thus alter the grassland productivity. Studies on grassland plant community composition, structure and diversity in response to ...Nutrient addition can affect the structure and diversity of grassland plant communities, thus alter the grassland productivity. Studies on grassland plant community composition, structure and diversity in response to nutrient addition have an important theoretical and practical significance for the scientific management of grassland, protection of plant diversity and the recovery of degraded grassland. A randomized block design experiment was conducted with six blocks of eight treatments each: control(no nutrient addition) and K, P, N, PK, NK, NP, and NPK addition. We evaluated plant composition, height, coverage, density, and aboveground biomass to estimate primary productivity and plant diversity. Results showed that all treatments increased primary productivity significantly(P〈0.05) with the exception of the K and the NPK treatments had the greatest effect, increasing aboveground biomass 2.46 times compared with the control(P〈0.05). One-way ANOVA and factorial analysis were used for the species richness, Shannon-Wiener index, Pielou index and aboveground biomass, and the relationships between the diversity indices and aboveground biomass were determined through linear regression. We found that fertilization altered the community structure; N(but not P or K) addition increased the proportion of perennial rhizome grasses and significantly reduced that of perennial forbs(P〈0.05), thus it presented a trend of decrease in species richness, Shannon-Wiener and Pielou indexex, respectively. Only the main effects of N had significant impacts on both the diversity indices and the aboveground biomass(P〈0.05), and the interactions between N-P, N-K, P-K and N-P-K could be neglected. With fertilization, plant diversity(correlation coefficient, –0.61), species richness(–0.49), and species evenness(–0.51) were all negatively linearly correlated with primary productivity. The correlations were all significant(P〈0.01). Scientific nutrient management is an effective way to improve grassland productivity, protect the plant diversity as well as recover the degraded grassland.展开更多
Intercropping is an important agronomic practice. However, assessment of intercropping systems using field experiments is often limited by time and cost. In this study, the suitability of using the DeNitrification DeC...Intercropping is an important agronomic practice. However, assessment of intercropping systems using field experiments is often limited by time and cost. In this study, the suitability of using the DeNitrification DeComposition(DNDC) model to simulate intercropping of maize(Zea mays L.) and soybean(Glycine max L.) and its aftereffect on the succeeding wheat(Triticum aestivum L.) crop was tested in the North China Plain. First, the model was calibrated and corroborated to simulate crop yield and nitrogen(N) uptake based on a field experiment with a typical double cropping system. With a wheat crop in winter, the experiment included five treatments in summer: maize monoculture, soybean monoculture, intercropping of maize and soybean with no N topdressing to maize(N0), intercropping of maize and soybean with 75 kg N ha–1topdressing to maize(N75), and intercropping of maize and soybean with 180 kg N ha–1topdressing to maize(N180). All treatments had 45 kg N ha–1as basal fertilizer. After calibration and corroboration, DNDC was used to simulate long-term(1955 to 2012) treatment effects on yield. Results showed that DNDC could stringently capture the yield and N uptake of the intercropping system under all N management scenarios, though it tended to underestimate wheat yield and N uptake under N0 and N75. Long-term simulation results showed that N75 led to the highest maize and soybean yields per unit planting area among all treatments, increasing maize yield by 59% and soybean yield by 24%, resulting in a land utilization rate 42% higher than monoculture. The results suggest a high potential to promote soybean production by intercropping soybean with maize in the North China Plain, which will help to meet the large national demand for soybean.展开更多
Utilization and transfer of nitrogen (N)in a strip intercropping system of garlic (Allium safivum L.) and broad bean (Vicia faba L.) have been investigated rarely. The objectives of this study were to quantify N...Utilization and transfer of nitrogen (N)in a strip intercropping system of garlic (Allium safivum L.) and broad bean (Vicia faba L.) have been investigated rarely. The objectives of this study were to quantify N uptake and utilization by intercropped broad bean and garlic and determine the magnitude of N transfer from broad bean to garlic. Field and pot trials were carried out in the Erhai Lake Basin in China using ^15N tracer applied to the soil or injected into broad bean plants. Strip intercropping of garlic and broad bean increased N absorption (47.2%) compared with sole crop broad bean (31.9%) or sole crop garlic (40.7%) and reduced soil residual N. Nearly 15% of 15N injected into petioles of broad bean intercropped with garlic was recovered in garlic at harvest, suggesting that N could be transferred from broad bean to strip intercropped garlic. The findings provide a basis for evaluating legumes' role in optimizing N fertilization when intercropped with non-legumes.展开更多
This study was designed to find out an optimised planting system of reducing non-point (source) pollution by analyzing the reasons and the factors of influence non-point pollution in farmland of Erhai Lake basin. Th...This study was designed to find out an optimised planting system of reducing non-point (source) pollution by analyzing the reasons and the factors of influence non-point pollution in farmland of Erhai Lake basin. The results showed that incomes, residual nitrogen in soil, and the loss of nitrogen in surface water in rice-garlic system were higher than those in rice-fava bean system. There were positive correlations between the nitrogen loss of farmland, nitrogen inputs, residual nitrogen in soil, and incomes of farmland. Economic benefits and environment benefits are both appropriate, if the area of rice-garlic system would be reduced to 53% and the area of rice-fava bean system increased to 36% of total cropping area in the investigated watershed. Adjustment of planting structure and introduction of reasonable rotation systems is considered an effective measure of controlling agricultural non-point pollution in watersheds of Erhai Lake.展开更多
Nitrogen(N) deficiency is one of the main factors limiting maize(Zea mays L.) productivity. Genetic improvement of root traits could improve nitrogen use efficiency. An association panel of 461 maize inbred lines was ...Nitrogen(N) deficiency is one of the main factors limiting maize(Zea mays L.) productivity. Genetic improvement of root traits could improve nitrogen use efficiency. An association panel of 461 maize inbred lines was assayed for root growth at seedling emergence under high-nitrate(HN, 5 mmol L^(-1))and low-nitrate(LN, 0.05 mmol L^(-1)) conditions. Twenty-one root traits and three shoot traits were measured. Under LN conditions, the root-to-shoot ratio, root dry weight, total root length, axial root length,and lateral root length on the primary root were all increased. Under LN conditions, the heritability of the plant traits ranged from 0.43 to 0.82, a range much wider than that of 0.27 to 0.55 observed under HN conditions. The panel was genotyped with 542,796 high-density single-nucleotide polymorphism(SNP) markers. Totally 328 significant SNP markers were identified using either mixed linear model(MLM) or general linear model analysis, with 34 detected by both methods. In the 100-kb intervals flanking these SNP markers, four candidate genes were identified. Under LN conditions, the protoporphyrinogen IX oxidase 2 gene was associated with total root surface area and the DELLA protein-encoding gene was associated with the length of the visible lateral root zone of the primary root. Under HN conditions, a histone deacetylase gene was associated with plant height. Under both LN and HN conditions, the gene encoding MA3 domain-containing protein was associated with the first whorl crown root number. The phenotypic and genetic information from this study may be exploited for genetic improvement of root traits aimed at increasing NUE in maize.展开更多
This study was conducted to investigate the combined effects of elevated CO2 levels and cadmium (Cd) on the root morphological traits and Cd accumulation in Lolium multiflorum Lam.and Lolium perenne L.exposed to two C...This study was conducted to investigate the combined effects of elevated CO2 levels and cadmium (Cd) on the root morphological traits and Cd accumulation in Lolium multiflorum Lam.and Lolium perenne L.exposed to two CO2 levels (360 and 1000 μl/L) and three Cd levels (0,4,and 16 mg/L) under hydroponic conditions.The results show that elevated levels of CO2 increased shoot biomass more,compared to root biomass,but decreased Cd concentrations in all plant tissues.Cd exposure caused toxicity to both Lolium species,as shown by the restrictions of the root morphological parameters including root length,surface area,volume,and tip numbers.These parameters were significantly higher under elevated levels of CO2 than under ambient CO2,especially for the number of fine roots.The increases in magnitudes of those parameters triggered by elevated levels of CO2 under Cd stress were more than those under non-Cd stress,suggesting an ameliorated Cd stress under elevated levels of CO2.The total Cd uptake per pot,calculated on the basis of biomass,was significantly greater under elevated levels of CO2 than under ambient CO2.Ameliorated Cd toxicity,decreased Cd concentration,and altered root morphological traits in both Lolium species under elevated levels of CO2 may have implications in food safety and phytoremediation.展开更多
Here, the ozone-treated domestic sludge was diluted up to four different multiples and utilized as a nutritional source for hydroponic lettuce growth. Additionally, lettuce was cultured using the modified Hoagland nut...Here, the ozone-treated domestic sludge was diluted up to four different multiples and utilized as a nutritional source for hydroponic lettuce growth. Additionally, lettuce was cultured using the modified Hoagland nutrient solution as a control. The effects of ozone-treated domestic sludge on lettuce growth and nutrition were studied. Results showed that the lettuce treated with modified Hoagland inorganic nutrient solution had increased leaf number, plant height, fresh weight and dry weight compared to those treated with the ozone-treated domestic sludge dilution (P〈0.05). However, the lettuce cultivated with the 2-fold ozone-treated sludge dilution showed significantly higher (P〈0.05) contents of chlorophyll, soluble sugar and ascorbic acid (Vc) compared to that treated with modified Hoagland nutrient solution. And the nitrate concentration in the lettuce cultured with the 2-fold ozone-treated sludge dilution was 53.93% less than that cultured with the modified Hoagland nutrient solution, which was a significant improvement (P〈0.05). This study suggested that the 2-fold ozone-treated sludge dilution is optimal for lettuce hydroponic nutrient requirements.展开更多
Edible oil is an important part of the human daily diet,which is popular in the food industry.People are paying increasing attention to the safety of edible oil as flawed oils have caused enormous international losses...Edible oil is an important part of the human daily diet,which is popular in the food industry.People are paying increasing attention to the safety of edible oil as flawed oils have caused enormous international losses and posed a huge threat to consumer health issues.Therefore,it is necessary and important to analyze the quality and safety of oil product.In the present study,we particularly reviewed recent literature on analysis of emerging pollutants in edible oil including mycotoxins,pesticide residues and heavy metals.In addition,a series of emerging analytical technologies(HPLC,LC-MS/MS and GC-MS)for these contaminants were also summarized in this paper.展开更多
基金supported by the Central Public-interest Scientific Institution Basal Research Fund(No.Y2024QC29)the Central Public-interest Scientific Institution Basal Research Fund(Nos.2024-jbkyywf-lwj and 2024-jbkyywf-zyj).
文摘The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to its rich mineral and geothermal resources.This review provides a comprehensive analysis of As content,focusing on its distribution,environmental migration,and transformation behavior across the plateau.The review further evaluates the distribution of As in different functional areas,revealing that geothermal fields(107.2 mg/kg),mining areas(53.8 mg/kg),and croplands(39.3 mg/kg)have the highest As concentrations,followed by river and lake sediments and adjacent areas(33.1 mg/kg).These elevated levels are primarily attributed to the presence of As-rich minerals,such as arsenopyrite and pyrite.Additionally,human activities,including mining and geothermal energy production,exacerbate the release of As into the environment.The review also highlights the role of localmicroorganisms,particularly those fromthe phyla Proteobacteria and Actinobacteria,which possess As metabolic genes that facilitate As translocation.Given the unique climatic conditions of the plateau,conventionalmethods for As controlmay not be fully effective.However,the review identifies promising remediation strategies that are environmentally adaptable,such as the use of local microorganisms,specific adsorbents,and integrated technologies,which offer potential solutions for managing and utilizing Ascontaminated soils on the plateau.
基金the financial support from the National Natural Science Foundation of China(No.22178181)the Fundamental Research Funds for the Central Universities(Nankai University(No.63253204))。
文摘Achieving sustainable energy and chemical production has become an important issue for human society.Photocatalysis has attracted much attention due to its ability to harness solar energy to drive chemical reactions.Metal sulfide-based photocatalysts(e.g.,Cd S,Zn In2S4)have shown substantial potential in biomass-based hydroxyl compound valorization.In this review,we summarize the recent progress in metal sulfide-based photocatalysts for the photo upgrading of biomass-derived hydroxyl compounds coupled with reduction reactions(e.g.,CO_(2)reduction,H_(2)O_(2)generation,and H_(2)evolution).The mechanism of biomass redox reactions is discussed,highlighting the potential of realizing the valorization of biomass-derived compounds coupled with the reduction reactions,which is beneficial for researchers to actively explore biomass biorefinery pathways in order to modulate the selectivity of the valueadded products.Various modification strategies are presented,including elemental doping,defect engineering,heterojunction construction,and cocatalyst loading.These strategies modulate the energy band structure,surface electron density,and built-in electric field strength of metal sulfide-based photocatalysts,thereby enhancing their photocatalytic performance.The challenges and prospects of metal sulfidebased photocatalysts in biomass valorization are analyzed.This approach contributes to the development of photocatalysts that can accelerate biomass photo-upgrading coupling reactions.This review aims to provide deeper insights into the photocatalytic biorefinery pathways and contribute to the development of functionalized photocatalysts that can accelerate biomass photo upgrading,highlighting the synergistic effects of multiple coupling reactions.
基金supported by the Youth innovation Program of Chinese Academy of Agricultural Sciences(No.Y2023QC32)the foundation of Tianjin Natural Science Foundation(No.22JCQNJC01460)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(Agro-Environmental Protection Institute,Ministry of Agricultural and Rural Affairs)and the Youth Talent Project of Agro-Environmental Protection Institute,Ministry of Agricultural and Rural Affairs(Xu Yan).
文摘The exponential growth of antibiotic-resistant bacteria and antibiotic-resistant genes(ARGs)in soil-crop systems in recent years has posed a great challenge to ecological security and human health.While many studies have documented the residues of ARGs in soils and crops,but little is known about who drives the proliferation of ARGs in farming systems and what their underlying mechanisms are.Herein,we explored the occurrence and proliferating behavior of ARGs in soil-crop environments in terms of root secretions and plant volatiles.This review highlighted that plant root secretions and volatile organic compounds(VOCs)served as key substances mediating the development of antibiotic resistance in the soil-crop system.Still,there is controversy here as to plant root secretions promote the ARGs proliferation or inhibit.Some studies indicated that root secretions can suppress the colonization of ARGs,mainly attributed by the production of bluntedmetabolic enzymes and blocking of cellular exocytosis systems.Whereas the others have evidenced that root secretions can promote ARGs proliferation,primarily by altering the structure of microbial communities to influence species interactions and thus indirectly affect the proliferation of ARGs.Also,VOCs can act as molecular signals to convey antibiotic resistance information to their neighbors,which in turn drive the up-regulation of ARGs expression.Even so,the mechanism by which VOC-driven antibiotic resistance acquisition and proliferation need to be further probed.Overall,this review contributed to the development of products and technologies to impede the ARGs proliferation in agricultural environment.
基金supported by the National Natural Science Foundation of China(No.42077299)the Innovation Program of Chinese Academy of Agricultural Sciences(No.Y2024QC29).
文摘Formamide condensation with Ni can generate the N–C structure,widely recognized as an efficient catalyst for electrocatalytic CO_(2) reduction reaction(CO_(2)RR).To improve the utilization efficiency of Ni atoms,we introduced metal oxides as substrates to modulate the growth of a formamide-Ni(FA-Ni)condensate.FA-Ni@TiO_(2) demonstrated 2.8 times higher partial CO current density and Ni turnover frequency than FA-Ni,which were also higher than those of other FA-Ni@metal oxides,including ZrO_(2),Al_(2)O_(3),Fe_(2)O_(3),and ZnO.The improved performance of CO_(2)RR can be attributed to the Ni content exposed on FA-Ni@TiO_(2) being twice that of the raw FA-Ni condensate.The Fourier transform infrared results suggested that formamide was adsorbed on TiO_(2) via the-CHO group,exposing-NH_(2) for potential interaction with Ni.As a result,Ni atoms were predispersed on the TiO_(2) surface.By contrast,the dispersion of Ni atoms was not enhanced by other metal oxides,such as Al_(2)O_(3),Fe_(2)O_(3),and ZnO,owing to the robust acidity of their surface sites.These metal oxides adsorbed formamide via-NH_(2),leading to the absence of extra-NH_(2) available for binding to Ni atoms.This study provides new insights into the development of appropriate substrates for single-atom catalysts.
基金financial support of the National Natural Science Foundation of China(No.42230706)the Outstanding Youth Science Fund(Overseas)of Shandong Provincial Natural Science Foundation(No.2022HWYQ-015)+1 种基金the Taishan Scholars Project Special Fund(No.tsqn202211039)Qilu Youth Talent Program of Shandong University(No.61440082163171)。
文摘The removal of highly toxic arsenic(As)and antimony(Sb)contaminants in water by adsorption presents a great challenge worldwide.Conventional adsorbents exhibit insufficient efficacy for removing pentavalent oxyanions,As(Ⅴ)and Sb(Ⅴ),which are predominant compared with the trivalent species,As(Ⅲ)and Sb(Ⅲ),in surface waters.Here,we synthesized a novel composite adsorbent,amine-functionalized polystyrene resin loaded with nano TiO_(2)(Am PSd-Ti).The mm-scale spheres showed outstanding adsorption capacities for As(Ⅲ),As(Ⅴ),Sb(Ⅲ),and Sb(Ⅴ)at 73.85,153.29,86.80,and 123.71 mg/g,respectively.Am PSd-Ti exhibited selective adsorption for As and Sb in the presence of Cl^(-),NO_(3)^(-),SO_(4)^(2-),and F^(-).As and Sb were adsorbed by the nano-sized TiO_(2)confined in the porous resin via forming innersphere complexes.The protonated amine groups enhanced the adsorption of As(Ⅴ)and Sb(Ⅴ)by electrostatic attraction and hydrogen bonding,which was confirmed by experimental results and molecular dynamics simulations.Fixed-bed column tests showed breakthrough curves with adsorption capacities of1.38 mg/g(6600 BV)and 6.65 mg/g(1260 BV)upon treating real As-contaminated groundwater and Sbcontaminated industrial wastewater.Our study highlights a feasible strategy by incorporating inorganic metal oxides into organic polymers to achieve highly efficient removal of As and Sb in real-world scenarios.
基金supported by the National Natural Science Foundation of China(Nos.52470114 and 52022104)the National Key R&D Program of China(No.2022YFC3702802)the Youth Innovation Promotion Association,CAS(No.Y2021020).
文摘In recent years,ozone has become one of the key pollutants affecting the urban air qual-ity.Direct catalytic decomposition of ozone emerges as an effective method for ozone re-moval.Field experimentswere conducted to evaluate the effectiveness of exteriorwall coat-ings with ozone decomposition catalysts for ozone removal in practical applications.ANSYS 2020R1 software was first used for simulation and analysis of ozone concentration and flow fields to investigate the decomposition boundary of these wall coatings.The results show that the exterior wall coatings with manganese-based catalysts can effectively reduce the ozone concentration near the wall coating.The ozone decomposition efficiency is nega-tively correlated with the distance fromthe coating and the decomposition boundary range is around 18 m.The decomposition boundary will increase with the increase of tempera-ture,and decrease with the increase of the wind speed and the relative humidity.These results underscore the viability of using exterior wall coatings with catalysts for controlling ozone pollution in atmospheric environments.This approach presents a promising avenue for addressing ozone pollution through self-purifying materials on building external wall.
基金supported by the Central Public Research Institutes Basic Funds for Research and Development, China (No. 2016-szjj-wrxf-lxf)the National Natural Science Foundation of China (No. 41401362)the Funds for Science and Technology Innovation Project from the Chinese Academy of Agricultural Sciences (No. CAAS-XTCX-2016018)
文摘Heavy metal contamination of agricultural soils poses risks and hazards to humans. The remediation of heavy metal-polluted soils has become a hot topic in environmental science and engineering. In this review, the application of clay minerals for the remediation of heavy metal-polluted agricultural soils is summarized, in terms of their remediation effects and mechanisms, influencing factors, and future focus. Typical clay minerals, natural sepiolite, palygorskite, and bentonite, have been widely utilized for the in-situ immobilization of heavy metals in soils, especially Cd-polluted paddy soils and wastewater-irrigated farmland soils. Clay minerals are able to increase soil pH, decrease the chemical-extractable fractions and bioavailability of heavy metals in soils, and reduce the heavy metal contents in edible parts of plants. The immobilization effects have been confirmed in field-scale demonstrations and pot trials. Clay minerals can improve the environmental quality of soils and alleviate the hazards of heavy metals to plants. As main factors affecting the immobilization effects, the pH and water condition of soils have drawn academic attention. The remediation mechanisms mainly include liming, precipitation, and sorption effects. However, the molecular mechanisms of microscopic immobilization are unclear. F^ture studies should focus on the long-term stability and improvement of clay minerals in order to obtain a better remediation effect.
基金supported by the National Natural Science Foundation of China (Nos.41977274, 41807123)the Shaanxi Province Key Research & Development Plan (No.2018ZDXMSF-022)the Scientific Research Program Funded by Shaanxi Provincial Education Department (No.18JK0100).
文摘Phytoremediation is a cost-effective and environment-friendly strategy for decontaminating heavy-metal-contaminated soil.However, the practical use of phytoremediation is constrained by the low biomass of plants and low bioavailability of heavy metals in soil.A pot experiment was conducted to investigate the effects of the metal chelator ethylenediaminetetraacetic acid(EDTA) and EDTA in combination with plant growth-promoting rhizobacteria(Burkholderia sp.D54 or Burkholderia sp.D416) on the growth and metal uptake of the hyperaccumulator Sedum alfredii Hance.According to the results, EDTA application decreased shoot and root biomass by 50% and 43%, respectively.The soil respiration and Cd,Pb, Zn uptake were depressed, while the photosynthetic rate, glutathione and phytochelatin(PC) contents were increased by EDTA application.Interestingly, Burkholderia sp.D54 and Burkholderia sp.D416 inoculation significantly relieved the inhibitory effects of EDTA on plant growth and soil respiration.Compared with the control, EDTA + D416 treatment increased the Cd concentration in shoots and decreased the Pb concentration in shoots and roots, but did not change the Zn concentration in S.alfredii plants.Furthermore,EDTA, EDTA + D54 and EDTA + D416 application increased the cysteine and PC contents in S.alfredii(p < 0.05);among all tested PCs, the most abundant species was PC2, and compared with the control, the PC2 content was increased by 371.0%, 1158.6% and 815.6%,respectively.These results will provide some insights into the practical use of EDTA and PGPR in the phytoremediation of heavy-metal-contaminated soil by S.alfredii.
基金supported by the National Basic Research Program (973) of China (No. 2005CB121104)the National Natural Science Foundation of China (No.41071145)
文摘Sequential extraction procedure was applied to assess the dynamics of solid-phase transformation of added Cu, Pb, Cd, and Hg in a typical Chinese paddy soil incubated under three moisture regimes (75% field capacity, wetting-drying cycle, and flooding). The heavy metals spiked in the soil were time-dependently transferred from the easily extractable fraction (the exchangeable fraction) into less labile fractions (Fe-Mn oxide- and organic matter-bound fractions), and thus reduced lability of the metals. No significant changes were found for the carbonate-bound and residual fractions of the heavy metals in the soil during the whole incubation. Change rate of the mobility factor (MF), a proportion of weakly bound fractions (exchangeable and carbonate-bound) in the total metal of soil, reflected the transformation rate of metal speciation from the labile fractions toward stable fractions. It was found that soil moisture regime did not change the direction and pathways of transformation of metal speciation, but it significantly affected the transformation rate. In general, the paddy soil under flooding regime had higher metal reactivity compared with 75% field capacity and wetting-drying cycle regimes, resulting in the more complete movement of metals toward stable fractions. This might be related to the increased pH, precipitation of the metals with sulfides and higher concentration of amorphous Fe oxides under submerged condition.
基金supported by the National Natural Science Foundation of China (No. 41501340)the Zhejiang Provincial Natural Science Foundation of China (No. LQ14D010002)
文摘The pollution of soils by heavy metals has dramatically increased in recent decades. Phytoextraction is a technology that extracts elements from polluted soils using hyperaccumulator plants. The selection of appropriate plant materials is an important factor for successful phytoextraction in field. A field study was conducted to compare the efficiency of six high-biomass forage species in their phytoextraction of heavy metals(Cd, Pb, and Zn) from contaminated soil under two harvesting strategies(double harvesting or single harvesting). Among the tested plants, amaranth accumulated the greatest amounts of Cd and Zn, whereas Rumex K^(-1) had the highest amount of Pb in the shoot under both double and single harvesting. Furthermore, double harvesting significantly increased the shoot biomass of amaranth, sweet sorghum and sudangrass and resulted in higher heavy metal contents in the shoot. Under double harvesting, the total amounts of extracted Cd, Pb and Zn(i.e., in the first plus second crops) for amaranth were 945, 2 650 and 12 400 g ha^(-1), respectively, the highest recorded among the six plant species. The present results indicate that amaranth has great potential for the phytoextraction of Cd from contaminated soils. In addition, the double harvesting method is likely to increase phytoextraction efficiency in practice.
基金the National Key Research and Development Program of China(No.2017YFD0801003)。
文摘Zero-valent iron amended biochar(ZVIB)has been proposed as a promising material in immobilizing heavy metals in paddy fields.In this study,the impacts of p H of ZVIB(p H 6.3 and p H 9.7)and watering management techniques(watering amount in the order of CON(control,5/72)>3/72>1-3/72>3/100>1/72,with 5/72,for example,representing irrigation given to 5 cm above soil surface in 72 hr regular interval)on As and Cd bioavailability for rice and its grain yield(Yield BR)were investigated in a pot experiment.Brown rice As(As BR)content was irrelative to the watering treatments,while significantly decreased(>50%)with the addition of both ZVIB materials.The diminutions of brown rice Cd(Cd BR)content as well as the Yield BR were highly dependent on both the soil amendment materials’p H and watering amount.Among all the watering treatments,3/72 treatment(15%less irrigation water than the CON)with ZVIB 6.3 amendment was the optimum fit for simultaneous reduction of As BR(50%)and Cd BR contents(19%)as well as for significant increment(12%)of the Yield BR.Although high pH(9.7)ZVIB application could also efficiently decrease As and Cd contents in brown rice,it might risk grain yield lost if appropriate(e.g.3/72 in our study)watering management technique was not chosen.Therefore,ZVIB would be an environmentally friendly option as an amendment material with proper selection of watering management technique to utilize As and Cd co-contaminated arable soils safely for paddy cultivation.
基金Supported by the Fundamental Research Funds of Central Welfare Scientific Research Institutes(2013-szjj-lzq-04)the Agroecological Environment Protection Program(2013-072)
文摘Soils in part of rice production areas have been seriously contaminated by cadmium (Cd). Rice with high Cd content over allowable limit produced in these areas is widely concerned. Low accumulation varieties can remarkably decrease the Cd content in rice as well as the risk of food safety. The translocation of Cd either from soil to root system or from roots to aboveground parts is identified by a lot of ion transport proteins. Transport efficiency of Cd in some rice varieties is regulated by special metal ionic transporters. However, most varieties transport Cd by cation transporters or universal ionic transporters. Both the expression levels and time of gens controlling ionic transporters directly influence the Cd transport rates inside rice plant and the accumulation amount in different organs. Screening and utilizing specific Cd transport genes are the genetic basis of breeding low accumulation varieties.
基金project was supported by the National Natural Science Foundation of China (31170435)the Key Technologies R&D Program of China during the 12th Five-Year Plan period (2012BAD13B07)+1 种基金the Fundamental Research Laboratory of the Central-Level Nonprofit Research Institutes, Chinathe Open Fund of the Key Laboratory of Environmental Quality in the Ministry of Agriculture and Agricultural Environment and Safety of Agricultural Products in Tianjin, China
文摘Nutrient addition can affect the structure and diversity of grassland plant communities, thus alter the grassland productivity. Studies on grassland plant community composition, structure and diversity in response to nutrient addition have an important theoretical and practical significance for the scientific management of grassland, protection of plant diversity and the recovery of degraded grassland. A randomized block design experiment was conducted with six blocks of eight treatments each: control(no nutrient addition) and K, P, N, PK, NK, NP, and NPK addition. We evaluated plant composition, height, coverage, density, and aboveground biomass to estimate primary productivity and plant diversity. Results showed that all treatments increased primary productivity significantly(P〈0.05) with the exception of the K and the NPK treatments had the greatest effect, increasing aboveground biomass 2.46 times compared with the control(P〈0.05). One-way ANOVA and factorial analysis were used for the species richness, Shannon-Wiener index, Pielou index and aboveground biomass, and the relationships between the diversity indices and aboveground biomass were determined through linear regression. We found that fertilization altered the community structure; N(but not P or K) addition increased the proportion of perennial rhizome grasses and significantly reduced that of perennial forbs(P〈0.05), thus it presented a trend of decrease in species richness, Shannon-Wiener and Pielou indexex, respectively. Only the main effects of N had significant impacts on both the diversity indices and the aboveground biomass(P〈0.05), and the interactions between N-P, N-K, P-K and N-P-K could be neglected. With fertilization, plant diversity(correlation coefficient, –0.61), species richness(–0.49), and species evenness(–0.51) were all negatively linearly correlated with primary productivity. The correlations were all significant(P〈0.01). Scientific nutrient management is an effective way to improve grassland productivity, protect the plant diversity as well as recover the degraded grassland.
基金supported by the National Natural Science Foundation of China (31701995 and 31572208)the National Key Research & Development Program of China (2016YFD0800101)+1 种基金the Newton Fund of UK-China (BB/N013484/1)supported by China Scholarship Council (2015-7169)
文摘Intercropping is an important agronomic practice. However, assessment of intercropping systems using field experiments is often limited by time and cost. In this study, the suitability of using the DeNitrification DeComposition(DNDC) model to simulate intercropping of maize(Zea mays L.) and soybean(Glycine max L.) and its aftereffect on the succeeding wheat(Triticum aestivum L.) crop was tested in the North China Plain. First, the model was calibrated and corroborated to simulate crop yield and nitrogen(N) uptake based on a field experiment with a typical double cropping system. With a wheat crop in winter, the experiment included five treatments in summer: maize monoculture, soybean monoculture, intercropping of maize and soybean with no N topdressing to maize(N0), intercropping of maize and soybean with 75 kg N ha–1topdressing to maize(N75), and intercropping of maize and soybean with 180 kg N ha–1topdressing to maize(N180). All treatments had 45 kg N ha–1as basal fertilizer. After calibration and corroboration, DNDC was used to simulate long-term(1955 to 2012) treatment effects on yield. Results showed that DNDC could stringently capture the yield and N uptake of the intercropping system under all N management scenarios, though it tended to underestimate wheat yield and N uptake under N0 and N75. Long-term simulation results showed that N75 led to the highest maize and soybean yields per unit planting area among all treatments, increasing maize yield by 59% and soybean yield by 24%, resulting in a land utilization rate 42% higher than monoculture. The results suggest a high potential to promote soybean production by intercropping soybean with maize in the North China Plain, which will help to meet the large national demand for soybean.
基金supported by the Special Fund for Agroscientific Research in the Public Interest,China (201003014)the National Natural Science Foundation of China (31460143)
文摘Utilization and transfer of nitrogen (N)in a strip intercropping system of garlic (Allium safivum L.) and broad bean (Vicia faba L.) have been investigated rarely. The objectives of this study were to quantify N uptake and utilization by intercropped broad bean and garlic and determine the magnitude of N transfer from broad bean to garlic. Field and pot trials were carried out in the Erhai Lake Basin in China using ^15N tracer applied to the soil or injected into broad bean plants. Strip intercropping of garlic and broad bean increased N absorption (47.2%) compared with sole crop broad bean (31.9%) or sole crop garlic (40.7%) and reduced soil residual N. Nearly 15% of 15N injected into petioles of broad bean intercropped with garlic was recovered in garlic at harvest, suggesting that N could be transferred from broad bean to strip intercropped garlic. The findings provide a basis for evaluating legumes' role in optimizing N fertilization when intercropped with non-legumes.
基金funded by the National Water Special Program of China during 11th Five-Year Plan period(2008ZX07105-002)
文摘This study was designed to find out an optimised planting system of reducing non-point (source) pollution by analyzing the reasons and the factors of influence non-point pollution in farmland of Erhai Lake basin. The results showed that incomes, residual nitrogen in soil, and the loss of nitrogen in surface water in rice-garlic system were higher than those in rice-fava bean system. There were positive correlations between the nitrogen loss of farmland, nitrogen inputs, residual nitrogen in soil, and incomes of farmland. Economic benefits and environment benefits are both appropriate, if the area of rice-garlic system would be reduced to 53% and the area of rice-fava bean system increased to 36% of total cropping area in the investigated watershed. Adjustment of planting structure and introduction of reasonable rotation systems is considered an effective measure of controlling agricultural non-point pollution in watersheds of Erhai Lake.
基金supported by the National Natural Science Foundation of China(31672221)。
文摘Nitrogen(N) deficiency is one of the main factors limiting maize(Zea mays L.) productivity. Genetic improvement of root traits could improve nitrogen use efficiency. An association panel of 461 maize inbred lines was assayed for root growth at seedling emergence under high-nitrate(HN, 5 mmol L^(-1))and low-nitrate(LN, 0.05 mmol L^(-1)) conditions. Twenty-one root traits and three shoot traits were measured. Under LN conditions, the root-to-shoot ratio, root dry weight, total root length, axial root length,and lateral root length on the primary root were all increased. Under LN conditions, the heritability of the plant traits ranged from 0.43 to 0.82, a range much wider than that of 0.27 to 0.55 observed under HN conditions. The panel was genotyped with 542,796 high-density single-nucleotide polymorphism(SNP) markers. Totally 328 significant SNP markers were identified using either mixed linear model(MLM) or general linear model analysis, with 34 detected by both methods. In the 100-kb intervals flanking these SNP markers, four candidate genes were identified. Under LN conditions, the protoporphyrinogen IX oxidase 2 gene was associated with total root surface area and the DELLA protein-encoding gene was associated with the length of the visible lateral root zone of the primary root. Under HN conditions, a histone deacetylase gene was associated with plant height. Under both LN and HN conditions, the gene encoding MA3 domain-containing protein was associated with the first whorl crown root number. The phenotypic and genetic information from this study may be exploited for genetic improvement of root traits aimed at increasing NUE in maize.
基金Project supported by the Central Public Research Institute Basic Fund for Research and Development (2008-jxh-1),Agro-environmental Protection Institute,Ministry of Agriculture,China
文摘This study was conducted to investigate the combined effects of elevated CO2 levels and cadmium (Cd) on the root morphological traits and Cd accumulation in Lolium multiflorum Lam.and Lolium perenne L.exposed to two CO2 levels (360 and 1000 μl/L) and three Cd levels (0,4,and 16 mg/L) under hydroponic conditions.The results show that elevated levels of CO2 increased shoot biomass more,compared to root biomass,but decreased Cd concentrations in all plant tissues.Cd exposure caused toxicity to both Lolium species,as shown by the restrictions of the root morphological parameters including root length,surface area,volume,and tip numbers.These parameters were significantly higher under elevated levels of CO2 than under ambient CO2,especially for the number of fine roots.The increases in magnitudes of those parameters triggered by elevated levels of CO2 under Cd stress were more than those under non-Cd stress,suggesting an ameliorated Cd stress under elevated levels of CO2.The total Cd uptake per pot,calculated on the basis of biomass,was significantly greater under elevated levels of CO2 than under ambient CO2.Ameliorated Cd toxicity,decreased Cd concentration,and altered root morphological traits in both Lolium species under elevated levels of CO2 may have implications in food safety and phytoremediation.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest, China (20130310104)the Key Technology R&D Program of Tianjin, China (12ZCZDNC09600)
文摘Here, the ozone-treated domestic sludge was diluted up to four different multiples and utilized as a nutritional source for hydroponic lettuce growth. Additionally, lettuce was cultured using the modified Hoagland nutrient solution as a control. The effects of ozone-treated domestic sludge on lettuce growth and nutrition were studied. Results showed that the lettuce treated with modified Hoagland inorganic nutrient solution had increased leaf number, plant height, fresh weight and dry weight compared to those treated with the ozone-treated domestic sludge dilution (P〈0.05). However, the lettuce cultivated with the 2-fold ozone-treated sludge dilution showed significantly higher (P〈0.05) contents of chlorophyll, soluble sugar and ascorbic acid (Vc) compared to that treated with modified Hoagland nutrient solution. And the nitrate concentration in the lettuce cultured with the 2-fold ozone-treated sludge dilution was 53.93% less than that cultured with the modified Hoagland nutrient solution, which was a significant improvement (P〈0.05). This study suggested that the 2-fold ozone-treated sludge dilution is optimal for lettuce hydroponic nutrient requirements.
基金funded by the Applied basic research plan of Hebei province-key basic research projects(17967502D)2020-Innovation Project-An Yi.
文摘Edible oil is an important part of the human daily diet,which is popular in the food industry.People are paying increasing attention to the safety of edible oil as flawed oils have caused enormous international losses and posed a huge threat to consumer health issues.Therefore,it is necessary and important to analyze the quality and safety of oil product.In the present study,we particularly reviewed recent literature on analysis of emerging pollutants in edible oil including mycotoxins,pesticide residues and heavy metals.In addition,a series of emerging analytical technologies(HPLC,LC-MS/MS and GC-MS)for these contaminants were also summarized in this paper.