Evolution and Efficiency Assessment of Pesticide and Fertiliser Inputs to Cultivated Land in China

Excessive use of pesticides and fertilisers has been a key issue limiting sustainable agricultural development. China is a typical pesticide- and chemical-fertiliser-dependent agricultural production area. We have matched the target indicators related to sustainable agricultural development (SDG1 and SDG2) and analysed the gap between China and four developed countries in terms of fertiliser and pesticide use intensity and efficiency from 2002 to 2016. We have used an improved Logarithmic Mean Divisia Index model and cluster analysis to identify the factors and effects driving increased pesticide and fertiliser inputs in China, and we discuss the exploratory effects of different provinces in reducing pesticide and fertiliser application and increasing efficiency. The findings reveal that (1) China is a typical pesticide- and fertiliser-dependent agricultural production area. The average combined fertiliser application efficiency in China from 2002 to 2016 was only 28% of that of the Netherlands, and the country’s average combined pesticide application efficiency was only 35% of that of the USA. (2) The most important of the three main drivers of the increase in pesticide and fertiliser inputs in China is the value added of the primary industry, contributing 56% for the period 2007–2016. (3) Further analysis at the provincial level according to four types—high-intensity high-yield type, high-intensity low-yield type, low-intensity high-yield type, and low-intensity low-yield type—clarified the provinces that should be focused on at the national level in terms of pesticide and fertiliser application reduction and efficiency increase in the future

A Rapid Screening Method for the Determination of Seventy Pesticide Residues in Soil Using Microwave-Assisted Extraction Coupled to Gas Chromatography and Mass Spectrometry

A rapid screening method using microwave-assisted extraction (MAE) in combination with gas chromatography and mass spectrometry for the determination of 70 pesticide residues in soil was established. The pesticides included 27 organophosphorus pesticides (OPPs), 29 organochlorine pesticides (OCPs), nine pyrethroids, and five carbamates. Parameters that could affect the efficiency of extraction, such as temperature, time, and solvent, were investigated. The condition of the extraction, under which recoveries of all 70 pesticides ranged from 70% to 120%, was optimized with a 1: 1 (V/V) mixture of acetone and hexane, a temperature of 100 degrees C, and an extraction time of 10 min. All compounds studied could be recovered in good yields and with relative standard deviations (RSDs) lower than 20%. The linearity of the method for all the pesticides was greater than 0.99 over a concentration range of 0.1-5 mu g/g. The detection limits varied from 0.5 to 211.25 ng/g. Interday and intraday precision analyses yielded RSDs of 1.2%-11.7% and 3.6%-15.1%, respectively. This method, which was as effective as Soxhlet extraction and accelerated solvent extraction (ASE), proved to be accurate and precise. When the proposed method was used to examine environmental samples, the obtained results were in good agreement with those obtained using Soxhlet extraction.A rapid screening method using microwave-assisted extraction (MAE) in combination with gas chromatography and mass spectrometry for the determination of 70 pesticide residues in soil was established. The pesticides included 27 organophosphorus pesticides (OPPs), 29 organochlorine pesticides (OCPs), nine pyrethroids, and five carbamates. Parameters that could affect the efficiency of extraction, such as temperature, time, and solvent, were investigated. The condition of the extraction, under which recoveries of all 70 pesticides ranged from 70% to 120%, was optimized with a 1: 1 (V/V) mixture of acetone and hexane, a temperature of 100 degrees C, and an extraction time of 10 min. All compounds studied could be recovered in good yields and with relative standard deviations (RSDs) lower than 20%. The linearity of the method for all the pesticides was greater than 0.99 over a concentration range of 0.1-5 mu g/g. The detection limits varied from 0.5 to 211.25 ng/g. Interday and intraday precision analyses yielded RSDs of 1.2%-11.7% and 3.6%-15.1%, respectively. This method, which was as effective as Soxhlet extraction and accelerated solvent extraction (ASE), proved to be accurate and precise. When the proposed method was used to examine environmental samples, the obtained results were in good agreement with those obtained using Soxhlet extraction

Point-of-care, multispectral, smartphone-based dermascopes for dermal lesion screening and erythema monitoring

Significance: The rates of melanoma and nonmelanoma skin cancer are rising across the globe. Due to a shortage of board-certified dermatologists, the burden of dermal lesion screening and erythema monitoring has fallen to primary care physicians (PCPs). An adjunctive device for lesion screening and erythema monitoring would be beneficial because PCPs are not typically extensively trained in dermatological care. Aim: We aim to examine the feasibility of using a smartphone-camera-based dermascope and a USB-camera-based dermascope utilizing polarized white-light imaging (PWLI) and polarized multispectral imaging (PMSI) to map dermal chromophores and erythema. Approach: Two dermascopes integrating LED-based PWLI and PMSI with both a smartphonebased camera and a USB-connected camera were developed to capture images of dermal lesions and erythema. Image processing algorithms were implemented to provide chromophore concentrations and redness measures. Results: PWLI images were successfully converted to an alternate colorspace for erythema measures, and the spectral bandwidth of the PMSI LED illumination was sufficient for mapping of deoxyhemoglobin, oxyhemoglobin, and melanin chromophores. Both types of dermascopes were able to achieve similar relative concentration results. Conclusion: Chromophore mapping and erythema monitoring are feasible with PWLI and PMSI using LED illumination and smartphone-based cameras. These systems can provide a simpler, more portable geometry and reduce device costs compared with interference-filter-based or spectrometer-based clinical-grade systems. Future research should include a rigorous clinical trial to collect longitudinal data and a large enough dataset to train and implement a machine learning-based image classifier.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Development Trend and Driving Factors of Agricultural Chemical Fertilizer Efficiency in China

In China, a high input of chemical fertilizers is currently required for a relatively low increase in agricultural production, and this has resulted in prominent nonpoint source pollution and problems related to the quality of agricultural products. These phenomena threaten China’s implementation of United Nations Sustainable Development Goal 2 (SDG-2). To explore agricultural chemical fertilizer efficiency and the factors driving the growth in chemical fertilizer use in China, as based on an international comparative analysis of China’s chemical fertilizer input, the development trend in the application level and the efficiency in the use of chemical fertilizer in China were subject to time series analysis, and the factors influencing change were identified and analyzed using the Logarithmic Mean Divisia Index (LMDI). The results show that: (1) The gap in agricultural chemical fertilizer efficiency is still large when comparing China with modern agricultural countries, and excessive fertilizer input is still a major problem. (2) The continuous growth in the total amount of chemical fertilizer applied in China during the past 18 years has contributed to the increase in chemical fertilizer application intensity, which provided a cumulative contribution of 85.52%, with smaller contributions from the planting structure and crop sown area. Based on the analysis of fertilizer application, the chemical fertilizer application intensity of the main grain crops was the most significant factor, accounting for about a 40.00% cumulative contribution. (3) Since 2015, the total amount of chemical fertilizers has been reduced through gradually improving the utilization rate of chemical fertilizers, reducing the application intensity of chemical fertilizers, and implementing the fallow rotation system and other measures. Of these, the reduction in application intensity was the most effective at reducing the overall amount of applied fertilizer. To meet the target for achieving sustainable agricultural development, China must still reduce its use of chemical fertilizers by at least 21.80 million tons. Based on the results of current measures and international experience, some suggestions for reducing fertilizer usage are provided

In Situ Determination of Bisphenol A in Beverage Using a Molybdenum Selenide/Reduced Graphene Oxide Nanoparticle Composite Modified Glassy Carbon Electrode

Due to the endocrine disturbing effects of bisphenol A (BPA) on organisms, rapid detection has become one of the most important techniques for monitoring its levels in the aqueous solutions associated with plastics and human beings. In this paper, a glassy carbon electrode (GCE) modified with molybdenum selenide/reduced graphene oxide (MoSe2/rGO) was fabricated for in situ determination of bisphenol A in several beverages. The surface area of the electrode dramatically increases due to the existence of ultra-thin nanosheets in a flower-like structure of MoSe2. Adding phosphotungstic acid in the electrolyte can significantly enhance the repeatability (RSD = 0.4%) and reproducibility (RSD = 2.2%) of the electrode. Under the optimized condition (pH = 6.5), the linear range of BPA was from 0.1 μM–100 μM and the detection limit was 0.015 μM (S/N = 3). When using the as-prepared electrode for analyzing BPA in beverage samples without any pretreatments, the recoveries ranged from 98–107%, and the concentrations were from below the detection limit to 1.7 μM, indicating its potential prospect for routine analysis of BPA

Contamination Status, Environmental Factor and Risk Assessment of Polychlorinated Biphenyls and Hexachlorobutadiene in Greenhouse and Open-Field Agricultural Soils across China

With the popularization and high-intensity utilization of greenhouse cultivation for crops growth, the pollution of greenhouse soils has been of concern. Therefore, a national-scale survey was conducted to investigate the contamination status, sources, influence factors and the risks of polychlorinated biphenyls (PCBs) and hexachlorobutadiene (HCBD) in greenhouse and nearby open-field soils. Contents of PCBs ranged from Pseudomonas as the PCBs-degrader in open-field soils. Although the higher values of mean contents were found in greenhouses, the health risks of ΣPCBs in open-field soils were higher than in greenhouse soils due to the higher percentages of high-toxicity PCBs, especially the carcinogenic risks to children (>10−6). This study provided a full insight on the contamination status and risks of PCBs and HCBD when guiding greenhouse agriculture activities