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An ex ante life cycle assessment of wheat with high biological nitrification inhibition capacity
2022
Leon, Ai | Guntur Venkata Subbarao | Kishii, Masahiro | Naruo Matsumoto | Kruseman, Gideon K.
It is essential to increase food production to meet the projected population increase while reducing environmental loads. Biological nitrification inhibition (BNI)-enabled wheat genetic stocks are under development through chromosome engineering by transferring chromosomal regions carrying the BNI trait from a wild relative (Leymus racemosus (Lam.) Tzvelev) into elite wheat varieties; field evaluation of these newly developed BNI-wheat varieties has started. Ten years from now, BNI-enabled elite wheat varieties are expected to be deployed in wheat production systems. This study aims to evaluate the impacts of introducing these novel genetic solutions on life cycle greenhouse gas (LC-GHG) emissions, nitrogen (N) fertilizer application rates and N-use efficiency (NUE). Scenarios were developed based on evidence of nitrification inhibition and nitrous oxide (N2O) emission reduction by BNI crops and by synthetic nitrification inhibitors (SNIs), as both BNI-wheat and SNIs slow the nitrification process. Scenarios including BNI-wheat will inhibit nitrification by 30% by 2030 and 40% by 2050. It was assumed that N fertilizer application rates can potentially be reduced, as N losses through N2O emissions, leaching and runoff are expected to be lower. The results show that the impacts from BNI-wheat with 40% nitrification inhibition by 2050 are assessed to be positive: a 15.0% reduction in N fertilization, a 15.9% reduction in LC-GHG emissions, and a 16.7% improvement in NUE at the farm level. An increase in ammonia volatilization had little influence on the reduction in LC-GHG emissions. The GHG emissions associated with N fertilizer production and soil N2O emissions can be reduced between 7.3 and 9.5% across the wheat-harvested area worldwide by BNI-wheat with 30% and 40% nitrification inhibition, respectively. However, the present study recommends further technological developments (e.g. further developments in BNI-wheat and the development of more powerful SNIs) to reduce environmental impacts while improving wheat production to meet the increasing worldwide demand.
显示更多 [+] 显示较少 [-]Can C-budget of natural capital be restored through conservation agriculture in a tropical and subtropical environment?
2022
de Moraes Sá, João Carlos | Lal, R. | Briedis, Clever | de Oliveira Ferreira, Ademir | Tivet, Florent | Inagaki, Thiago Massao | Potma Gonçalves, Daniel Ruiz | Canalli, Lutécia Beatriz | Burkner dos Santos, Josiane | Romaniw, Jucimare
Conservation agriculture through no-till based on cropping systems with high biomass-C input, is a strategy to restoring the carbon (C) lost from natural capital by conversion to agricultural land. We hypothesize that cropping systems based on quantity, diversity and frequency of biomass-C input above soil C dynamic equilibrium level can recover the natural capital. The objectives of this study were to: i) assess the C-budget of land use change for two contrasting climatic environments, ii) estimate the C turnover time of the natural capital through no-till cropping systems, and iii) determine the C pathway since soil under native vegetation to no-till cropping systems. In a subtropical and tropical environment, three types of land use were used: a) undisturbed soil under native vegetation as the reference of pristine level; b) degraded soil through continuous tillage; and c) soil under continuous no-till cropping system with high biomass-C input. At the subtropical environment, the soil under continuous tillage caused loss of 25.4 Mg C ha⁻¹ in the 0–40 cm layer over 29 years. Of this, 17 Mg C ha⁻¹ was transferred into the 40–100 cm layers, resulting in the net negative C balance for 0–100 cm layer of 8.4 Mg C ha⁻¹ with an environmental cost of USD 1968 ha⁻¹. The 0.59 Mg C ha⁻¹ yr⁻¹ sequestration rate by no-till cropping system promote the C turnover time (soil and vegetation) of 77 years. For tropical environment, the soil C losses reached 27.0 Mg C ha⁻¹ in the 0–100 cm layer over 8 years, with the environmental cost of USD 6155 ha⁻¹, and the natural capital turnover time through C sequestration rate of 2.15 Mg C ha⁻¹ yr⁻¹ was 49 years. The results indicated that the particulate organic C and mineral associate organic C fractions are the indicators of losses and restoration of C and leading C pathway to recover natural capital through no-till cropping systems.
显示更多 [+] 显示较少 [-]Episodes of high tropospheric ozone reduce nodulation, seed production and quality in soybean (Glycine max (L.) merr.) on low fertility soils
2021
Biancari, Lucio | Cerrotta, Clara | Menéndez, Analía I. | Gundel, Pedro E. | Martínez-Ghersa, M Alejandra
Driven by human activities, air pollution and soil degradation are threatening food production systems. Rising ozone in the troposphere can affect several physiological processes in plants and their interaction with symbiotic microorganisms. Plant responses to ozone may depend on both soil fertility and the ontogenetic stage in which they are exposed. In this work, we studied the effects of ozone episodes and soil fertility on soybean plants. We analysed soybean plant responses in the production of aboveground and belowground biomass, structural and functional attributes of rhizobia, and seed production and quality. The experiment was performed with plants grown in two substrates with different fertility (commercial soil, and soil diluted (50%, v/v) with sand). Plants were exposed to acute episodes of ozone during vegetative and reproductive stages. We observed that ozone significantly reduced belowground biomass (≈25%), nodule biomass (≈30%), and biological nitrogen fixation (≈21%). Plants exposed to ozone during reproductive stage growing in soil with reduced fertility had lower seed production (≈10% lower) and seed protein (≈12% lower). These responses on yield and quality can be explained by the observed changes in belowground biomass and nitrogen fixation. The negative impact of ozone on the symbiotic interaction with rhizobia, seed production and quality in soybean plants were greater in soils with reduced fertility. Our results indicate that food security could be at risk in the future if trends in ozone concentration and soil degradation processes continue to increase.
显示更多 [+] 显示较少 [-]Antibiotics degradation in soil: A case of clindamycin, trimethoprim, sulfamethoxazole and their transformation products
2017
Koba, Olga | Golovko, Oksana | Kodešová, Radka | Fér, Miroslav | Grabic, Roman
Twelve different soil types that represent the soil compartments of the Czech Republic were fortified with three antibiotics (clindamycin (CLI), sulfamethoxazole (SUL), and trimethoprim (TRI)) to investigate their fate. Five metabolites (clindamycin sulfoxide (CSO), hydroxy clindamycin sulfoxide (HCSO), S-(SDC) and N-demethyl clindamycin (NDC), N4-acetyl sulfamethoxazole (N4AS), and hydroxy trimethoprim (HTR)) were detected and identified using HPLC/HRMS and HRPS in the soil matrix in this study. The identities of CSO and N4AS were confirmed using commercially available reference standards.The parent compounds degraded in all soils. Almost all of the metabolites have been shown to be persistent in soils, with the exception of N4AS, which was formed and degraded completely within 23 days of exposure. The rate of degradation mainly depended on the soil properties.The PCA results showed a high dependence between the soil type and behaviour of the pharmaceutical metabolites.The mentioned metabolites can be formed in soils, and the most persistent ones may be transported to the ground water and environmental water bodies. Because no information on the effects of those metabolites on living organism are available, more studies should be performed in the future to predict the risk to the environment.
显示更多 [+] 显示较少 [-]Mapping lead concentrations in urban topsoil using proximal and remote sensing data and hybrid statistical approaches
2021
Shi, Tiezhu | Yang, Chao | Liu, Huizeng | Wu, Chao | Wang, Zhihua | Li, He | Zhang, Huifang | Guo, Long | Wu, Guofeng | Su, Fenzhen
Due to rapid urbanization in China, lead (Pb) continues to accumulate in urban topsoil, resulting in soil degradation and increased public exposure. Mapping Pb concentrations in urban topsoil is therefore vital for the evaluation and control of this exposure risk. This study developed spatial models to map Pb concentrations in urban topsoil using proximal and remote sensing data. Proximal sensing reflectance spectra (350–2500 nm) of soils were pre-processed and used to calculate the principal components as landscape factors to represent the soil properties. Other landscape factors, including vegetation and land-use factors, were extracted from time-sequential Landsat images. Two hybrid statistical approaches, regression kriging (RK) and geographically weighted regression (GWR), were adopted to establish prediction models using the landscape factors. The results indicated that the use of landscape factors derived from combined remote and proximal sensing data improved the prediction of Pb concentrations compared with useing these data individually. GWR obtained better results than RK for predicting soil Pb concentration. Thus, joint proximal and remote sensing provides timely, easily accessible, and suitable data for extracting landscape factors.
显示更多 [+] 显示较少 [-]A review on pesticides in flower production: A push to reduce human exposure and environmental contamination
2021
Pereira, Patrícia C.G. | Parente, Cláudio E.T. | Carvalho, Gabriel O. | Torres, João P.M. | Meire, Rodrigo O. | Dorneles, Paulo R. | Malm, Olaf
In several countries, flower import regulations are restricted to food security, by establishing maximum residue limits (MRL) for pesticides in flower-based food products and biosafety, in order to limit the circulation of vectors, pests and exotic species across borders. In this context, the lack of limits on pesticides in flower-products for ornamental purposes can influence the pesticide overuse in production areas, as well as the transfer of contaminated products between countries. Therefore, the purpose of this review was to discuss possible adverse effects on human and environmental health of pesticides used in floriculture, evaluating regulations on the use of these pesticides in the main importing and flower-producing countries. This review included 92 documents. The use of 201 compounds was identified by interviews and analytical measurements. Among them, 93 are banned by the European Union (EU), although 46.3 % of these compounds have been identified in samples from European countries. Latin American countries have a large number of scientific publications on pesticides in flower production (n = 51), while the EU and China have less studies (n = 24) and the United States and Japan have no studies. Regarding adverse health effects, poorer neurobehavioral development, reproductive disorders, congenital malformations and genotoxicity have been reported for residents of flower production areas and workers throughout the flower production cycle. Studies including water samples show overuse of pesticides, while environmental impacts are related to water and air contamination, soil degradation and adverse effects on the reproduction and development of non-target organisms. This review points out that the absence of MRL for non-edible flowers can be crucial for the trade of contaminated products across borders, including pesticides banned in importing countries. Furthermore, setting limits on flowers could reduce the use of pesticides in producing countries.
显示更多 [+] 显示较少 [-]Insights into acetate-mediated copper homeostasis and antioxidant defense in lentil under excessive copper stress
2020
Shahadat Hossain, Md. | Abdelrahman, Mostafa | Tran, Cuong Duy | Nguyen, Kien Huu | Chu, Ha Duc | Watanabe, Yasuko | Hasanuzzaman, Mirza | Mohsin, Sayed Mohammad | Fujita, Masayuki | Tran, Lam-son Phan
Gradual contamination of agricultural land with copper (Cu), due to the indiscriminate uses of fungicides and pesticides, and the discharge of industrial waste to the environment, poses a high threat for soil degradation and consequently food crop production. In this study, we combined morphological, physiological and biochemical assays to investigate the mechanisms underlying acetate-mediated Cu toxicity tolerance in lentil. Results demonstrated that high dose of Cu (3.0 mM CuSO₄. 5H₂O) reduced seedling growth and chlorophyll content, while augmenting Cu contents in both roots and shoots, and increasing oxidative damage in lentil plants through disruption of the antioxidant defense. Principle component analysis clearly indicated that Cu accumulation and increased oxidative damage were the key factors for Cu toxicity in lentil seedlings. However, acetate pretreatment reduced Cu accumulation in roots and shoots, increased proline content and improved the responses of antioxidant defense (e.g. increased catalase and glutathione-S-transferase activities, and improved action of glutathione-ascorbate metabolic pathway). As a result, excess Cu-induced oxidative damage was reduced, and seedling growth was improved under Cu stress conditions, indicating the role of acetate in alleviating Cu toxicity in lentil seedlings. Taken together, exogenous acetate application reduced Cu accumulation in lentil roots and shoots and mitigated oxidative damage by activating the antioxidant defense, which were the major determinants for alleviating Cu toxicity in lentil seedlings. Our findings provide mechanistic insights into the protective roles of acetate in mitigating Cu toxicity in lentil, and suggest that application of acetate could be a novel and economical strategy for the management of heavy metal toxicity and accumulation in crops.
显示更多 [+] 显示较少 [-]Oxidative stress parameters, DNA damage and expression of HSP70 and MT in midgut of Trachyderma hispida (Forskål, 1775) (Coleoptera: Tenebrionidae) from a textile industry area
2020
The textile mill industry is one of the major sources of pollution and contributors of metal contaminants to the environment. At the same time, the industry is important for global economy. Pollution caused by the textile industry is characteristic due to a unique set of potentially toxic substances. Darkling beetles (Coleoptera, Tenebrionidae), which live in all biogeographical regions, are especially common in soil quality and soil degradation studies. Our study was designed to assess long-term effects of textile industry (which generates specific pollution) on soil organisms, namely Trachyderma hispida. We especially wanted to find out what changes allow the species to survive and adapt to these specific conditions. Energy-dispersive X-ray spectroscopy of soil and midgut tissues of T. hispida sampled from a polluted site in the Edku textile industrial area in Egypt revealed a high accumulation of chemical elements, compared to a reference site. The concentration of elements in soil was well correlated with their concentration in the midgut of insects. Activity of superoxide dismutase, catalase, ascorbate peroxidase and glutathione S-transferase were negatively correlated with concentration of elements in soil and in the midgut. Meanwhile, malondialdehyde concentration in the midgut revealed an opposite tendency. DNA damage and expression of stress proteins, (HSP70 and metallothionein - MT) were elevated in insects from the polluted site. The activity of textile industry in the area of Edku undoubtedly causes an increase of soil pollution and, in consequence, causes a number of changes in the bodies of organisms living in these areas, including T. hispidus. Therefore, it is necessary to find a solution which limits the emission of waste from the textile industry, as well as to design modern strategies of processing, storing and utilizing it.
显示更多 [+] 显示较少 [-]Coupling strategies for ecotoxicological assessment of neonicotinoid insecticides based on their selective lethal effects: Design, screening, and regulation
2022
Zhao, Yuanyuan | Xixi Li, | Xinao Li, | Zheng, Maosheng | Zhang, Yimei | Li, Yu
The recently recognized adverse environmental and toxic effects of neonicotinoid insecticides (NNIs) on non-target organisms are alarming. A comprehensive design, screening, and regulatory system was developed to generate NNI derivatives and mutant receptors with selective-ecotoxicological effects to overcome such adverse effects. For ligand design, taking ACE-09 derivative as an example, the toxicity on non-target animals (aboveground: bees; underground: earthworms), plant absorption, and soil absorption decreased by 4.80% and 13.7%, 10.0%, and 121%, while the toxicity on target animals (aboveground: aphids; underground: B. odoriphagas), plant metabolism, and soil degradation increased by 70.2% and 51.7%, 5.08%, and 8.28%. For receptor modification, the ability of mutants to absorb ACE-09 derivative decreased by 31.0%, while the ability of mutants to metabolize ACE-09 derivative increased by 28.0% in scenario 2 (mainly plant selectivity); the ability of mutants to degrade ACE-09 derivative increased by 11.6% in scenario 3 (mainly soil selectivity). The above results indicated that the selective-ecotoxicological effects of ligand design and receptor modification were both improved. Additionally, the combined effects of the ACE-09 derivative on plant absorption and metabolic mutants improved by 31.1% and 31.4% in scenario 2, respectively, while the effect on microbial degradation mutant improved by 14.9%, indicating that there was a synergistic effect between ligand design and receptor modification. Finally, based on the interaction between the ACE-09 derivative and mutants, the optimal environmental factors that improved the selectivity of their ecotoxicological effects were determined. For example, alternate application of nitrogen and phosphorus fertilizers effectively reduced the oxidative damage to plants caused by NNI residues. The novel ligand-receptor joint modification method, combined with the regulation of environmental factors under multiple scenarios, can biochemically address the ecotoxicological concern and highlight the harmful effects of pesticides on the environment and non-target organisms.
显示更多 [+] 显示较少 [-]Role of Nitrogen in Assessing the Sustainability of Irrigated Areas: Case Study of Northern Mexico
2021
Gutiérrez, Mélida | Calleros-Rincón, Esperanza Yasmin | Espino-Valdés, María Socorro | Alarcón Herrera, María Teresa
World’s food production relies on crops grown in irrigated land to feed an increasing population. In the long term, irrigation agriculture may cause environmental deterioration to the area (soil degradation, aquifer contamination) and its surroundings (greenhouse gas emission, eutrophication) to compromise crop production. Three irrigated areas in northern Mexico (Yaqui Valley, Delicias, Comarca Lagunera) were examined with respect to the challenges to achieve sustainability using reported values of nitrogen (N) along with the conventional aquifer depletion and water contamination parameters. N₂O emissions, measured in only the Yaqui Valley, amounted to up to 4.5% of applied N, and nitrate losses to about 18%. The water tables of these aquifers are dropping at rates of 0.4 m year⁻¹ (Delicias) to 1.5 m year⁻¹ (Comarca Lagunera). High NO₃⁻ concentrations in the Comarca Lagunera (66.2% of wells above 10 mg L⁻¹ NO₃–N) pose a threat to human health. Although lower than 10 mg L⁻¹ NO₃–N in most wells, NO₃⁻ levels in Delicias and Yaqui Valley are increasing with time, although more data are needed to confirm the trend. Overall, and although the efforts by farmers still focus on increasing crop yield, awareness of the advantage of implementing measures towards sustainability is on the rise.
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