Publications by authors named "Liangquan Wu"

8 Publications

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Effects of nitrogen-enriched biochar on rice growth and yield, iron dynamics, and soil carbon storage and emissions: A tool to improve sustainable rice cultivation.

Environ Pollut 2021 Jun 16;287:117565. Epub 2021 Jun 16.

Key Laboratory of Humid Subtropical Eco-Geographical Process, Ministry of Education, Fujian Normal University, Fuzhou, 350007, China; CSIC, Global Ecology Unit, CREAF-CSIC-UAB, Bellaterra, 08193, Barcelona, Catalonia, Spain; CREAF, Cerdanyola del Vallès, 08193, Catalonia, Spain.

Biochar is often applied to paddy soils as a soil improver, as it retains nutrients and increases C sequestration; as such, it is a tool in the move towards C-neutral agriculture. Nitrogen (N) fertilizers have been excessively applied to rice paddies, particularly in small farms in China, because N is the major limiting factor for rice production. In paddy soils, dynamic changes in iron (Fe) continuously affect soil emissions of methane (CH) and carbon dioxide (CO); however, the links between Fe dynamics and greenhouse gas emissions, dissolved organic carbon (DOC), and rice yields following application of biochar remain unclear. The aims of this study were to examine the effects of two rates of nitrogen (N)-enriched biochar (4 and 8 t ha y) on paddy soil C emissions and storage, rice yields, and Fe dynamics in subtropical early and late rice growing seasons. Field application of N-enriched biochar at 4 and 8 t ha increased C emissions in early and late rice, whereas application at 4 t ha significantly increased rice yields. The results of a culture experiment and a field experiment showed that the application of N-enriched biochar increased soil Feconcentration. There were positive correlations between Feconcentrations and soil CO, CH, and total C emissions, and with soil DOC concentrations. On the other way around, these correlations were negative for soil Feconcentrations. In the soil culture experiment, under the exclusion of plant growth, N-enriched biochar reduced cumulative soil emissions of CH and CO. We conclude that moderate inputs of N-rich biochar (4 t ha) increase rice crop yield and biomass, and soil DOC concentrations, while moderating soil cumulative C emissions, in part, by the impacts of biochar on soil Fe dynamics. We suggest that water management strategies, such as dry-wet cycles, should be employed in rice cultivation to increase Fe oxidation for the inhibition of soil CH and CO production. Overall, we showed that application of 4 t ha of N-enriched biochar may represent a potential tool to improve sustainable food production and security, while minimizing negative environmental impacts.
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http://dx.doi.org/10.1016/j.envpol.2021.117565DOI Listing
June 2021

Orderly Curled Silica Nanosheets with a Small Size and Macromolecular Loading Pores: Synthesis and Delivery of Macromolecules To Eradicate Drug-Resistant Cancer.

ACS Appl Mater Interfaces 2020 Dec 16;12(52):57810-57820. Epub 2020 Dec 16.

Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing 210002, P.R. China.

Hierarchically organized silica nanomaterials have shown great promise for nanomedicine. However, the synthesis of silica nanomaterials with a small size and macromolecular loading pore is still a big challenge. Herein, orderly curled silica nanosheets (OCSNs) with a ∼42 nm diameter and orderly connected large channels (∼13.4 nm) were successfully prepared for the first time. The key to the formation of the unique structure (OCSNs) is using an oil/water reaction system with high concentrations of the surfactant and alkali. The prepared OCSNs exhibit a long blood circulation halftime (0.97 h) and low internalization in the reticuloendothelial system. Notably, the large superficial channels can concurrently house large guest molecules (siRNA) and chemotherapeutic drugs. Furthermore, drug-loaded OCSNs modified with polyglutamic acids can greatly increase the accumulation of incorporated siRNA and doxorubicin in solid tumors and restrain the growth of drug-resistant orthotopic breast cancer by inducing cell apoptosis. Overall, we report the preparation of hierarchically OCSNs; their small size and macromolecular loading pores are very promising for the delivery of large guest molecules and chemotherapeutic drugs for cancer therapy.
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http://dx.doi.org/10.1021/acsami.0c19497DOI Listing
December 2020

Soil Phosphorus Pools, Bioavailability and Environmental Risk in Response to the Phosphorus Supply in the Red Soil of Southern China.

Int J Environ Res Public Health 2020 10 10;17(20). Epub 2020 Oct 10.

International Magnesium Institute, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.

Excess phosphorus (P) accumulation in the soil can change the bioavailability of P and increase the leaching risks, but the quantitative evaluation of these responses in acidic red soil is lacking. This study aimed to investigate the composition of soil P fractions under different phosphorus apparent balances (PAB) in acidic red soil and the bioavailability and the leaching change-points of different P fractions. Five phosphorus (P) fertilization rates were applied (0, 16.38, 32.75, 65.50, 131.00 kg P·ha) in every sweet corn cultivation from the field experiment, and the treatments were marked as P0, P1, P2, P3, and P4, respectively. The PAB showed negative values in P0 and P1 which were -49.0 and -15.0 kg P·ha in two years, respectively. In contrast, PAB in P2 as well as in P3 and P4 were positive, the content ranging from 40.2 to 424.3 kg P·ha in two years. Per 100 kg ha P accumulate in the soil, the total P increased by 44.36 and 10.41 mg kg in the surface (0-20 cm) and subsurface (20-40 cm) soil, respectively. The content of inorganic P fractions, including solution phosphate (Sol-P), aluminum phosphate (Al-P), iron phosphate (Fe-P), reduction phosphate (Red-P), and calcium phosphate (Ca-P), significantly increased by 0.25, 16.22, 22.08, 2.04, and 5.08 mg kg, respectively, in surface soil per 100 kg ha P accumulated in the soil. Path analysis showed that the most important soil P fractions contributing to Olsen-P were Sol-P and Al-P, which can directly affect Olsen-P, and their coefficients were 0.24 and 0.73, respectively. Furthermore, the incubation experiments were conducted in the laboratory to investigate the leaching risk of different P fractions, and they showed Sol-P was a potential source of leaching, and the leaching change-points of Al-P and Fe-P were 74.70 and 78.34 mg·kg, respectively. Continuous P that accumulated in soil changed the composition of P fractions, and the bioavailability as well as the leaching risks increased. This is important in optimizing soil P fertilization management in agricultural ecosystems based on the bioavailability and critical levels for leaching of P fractions.
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http://dx.doi.org/10.3390/ijerph17207384DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7599965PMC
October 2020

Magnesium Deficiency Reduced the Yield and Seed Germination in Wax Gourd by Affecting the Carbohydrate Translocation.

Front Plant Sci 2020 11;11:797. Epub 2020 Jun 11.

Key Laboratory for New Technology Research of Vegetable, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China.

Magnesium (Mg) is a particular mineral nutrient greatly affecting the size and activity of sink organs. Wax gourd crop with its fruits having fresh weight up to 20-50 kg per single fruit serves as an excellent experimental plant species for better understanding the role of varied Mg nutrition in sink strength and yield formation. This study aimed to investigate the effects of Mg deficiency on fruit yield and seed vigor in wax gourd grown under field conditions. Plants were grown under field conditions until maturity with increasing soil Mg applications. At the beginning of fruit formation, leaves were used to analyze concentrations of sucrose, starch and Mg as well as phloem export of sucrose. At maturity, fruit yield was determined and the seeds collected were used in germination studies and starch analysis. Low Mg supply resulted in a significant impairment in fruit fresh yield, which was closely associated with higher accumulation of starch and sucrose in source leaves and lower amount of sucrose in phloem exudate. Seeds obtained from Mg deficiency plants exhibited lower amount of starch and substantial reduction in both germination capacity and seedling establishment when compared to the seeds from the Mg adequate plants. Our study revealed that magnesium deficiency significantly diminished fruit yield of field-grown wax gourd, most probably by limiting the carbohydrate transport from source organs to developing fruit. Ensuring sufficient Mg supply to plant species with high sink size such as wax gourd, during the reproductive growth stage, is a critical factor for achieving higher fruit yield formation and also better vigor of next-generation seeds.
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http://dx.doi.org/10.3389/fpls.2020.00797DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7300272PMC
June 2020

Magnesium Fertilization Improves Crop Yield in Most Production Systems: A Meta-Analysis.

Front Plant Sci 2019 24;10:1727. Epub 2020 Jan 24.

Department of Plant Nutrition, The Key Plant-Soil Interaction Lab, MOE, China Agricultural University, Beijing, China.

Magnesium deficiency is a frequently occurring limiting factor for crop production due to low levels of exchangeable Mg (ex-Mg) in acidic soil, which negatively affects sustainability of agriculture development. How Mg fertilization affects crop yield and subsequent physiological outcomes in different crop species, as well as agronomic efficiencies of Mg fertilizers, under varying soil conditions remain particular interesting questions to be addressed. A meta-analysis was performed with 570 paired observations retrieved from 99 field research articles to compare effects of Mg fertilization on crop production and corresponding agronomic efficiencies in different production systems under varying soil conditions. The mean value of yield increase and agronomic efficiency derived from Mg application was 8.5% and 34.4 kg kg respectively, when combining all yield measurements together, regardless of the crop type, soil condition, and other factors. Under severe Mg deficiency (ex-Mg < 60 mg kg), yield increased up to 9.4%, nearly two folds of yield gain (4.9%) in the soil containing more than 120 mg kg ex-Mg. The effects of Mg fertilization on yield was 11.3% when soil pH was lower than 6.5. The agronomic efficiency of Mg fertilizers was negatively correlated with application levels of Mg, with 38.3 kg kg at lower MgO levels (0-50 kg ha) and 32.6 kg kg at higher MgO levels (50-100 kg ha). Clear interactions existed between soil ex-Mg, pH, and types and amount of Mg fertilizers in terms of crop yield increase. With Mg supplementation, Mg accumulation in the leaf tissues increased by 34.3% on average; and concentrations of sugar in edible organs were 5.5% higher compared to non-Mg supplemented treatments. Our analysis corroborated that Mg fertilization enhances crop performance by improving yield or resulting in favorable physiological outcomes, providing great potentials for integrated Mg management for higher crop yield and quality.
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http://dx.doi.org/10.3389/fpls.2019.01727DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6992656PMC
January 2020

Soil acidification in Chinese tea plantations.

Sci Total Environ 2020 May 27;715:136963. Epub 2020 Jan 27.

Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China. Electronic address:

Soil acidification is a major problem in intensive agricultural systems and is becoming increasingly serious. Most research has reported the soil acidification of cereal crops, forests, and grasslands. However, there is no information about soil acidification under tea cultivation on a national scale. Therefore, we conducted a nationwide survey of soil acidification in the major tea-planting areas of China and used two nationwide surveys in three Chinese counties to evaluate changes in soil acidity over the past 20-30 years. Finally, the acidity of soil from forests and traditional and organic tea plantations was compared to evaluate the effects of agricultural management on soil acidification in tea plantations. Our results show that: (1) the average soil pH was 4.68 nationally and ranged from 3.96 to 5.48 in different provinces. Overall, 46.0% of the soil samples had a pH <4.5, which is too acidic for tea growth and only 43.9% had a soil pH of 4.5-5.5, which is optimal for tea growth. (2) In the past 20-30 years, the greatest soil acidification was observed in tea plantations; the pH decreased by 0.47 to 1.43, which is much greater than the decrease seen in fruit and vegetable systems (0.40 to 1.08) and cereals (0.30 to 0.89). (3) Compared with forests, tea cultivation with chemical fertilizer application caused serious soil acidification, while no significant acidification was observed at organic tea plantations. In conclusion, serious soil acidification occurs nationally in China, and organic management is an adaptive choice for sustainable tea growth.
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http://dx.doi.org/10.1016/j.scitotenv.2020.136963DOI Listing
May 2020

Diagnostic and prognostic significance of receptor-binding cancer antigen expressed on SiSo cells in lung-cancer-associated pleural effusion.

Clin Respir J 2018 Jan 21;12(1):279-284. Epub 2016 Jul 21.

Endoscopic Center of Nanjing Chest Hospital, Nanjing, Jiangsu, 210029, China.

Objectives: This study aimed to evaluate the diagnostic and prognostic value of pleural effusion levels of soluble receptor-binding cancer antigen expressed on SiSo cells (sRCAS1) in lung cancer patients with malignant pleural effusion (MPE).

Methods: Pleural effusion samples were collected from 78 patients with MPE, and from 48 patients with benign pleural effusion (BPE). Pleural effusion sRCAS1 concentrations were measured by enzyme-linked immunosorbent assay.

Results: MPE has significantly higher sRCAS1 levels than that of BPE (P < .01). With a cutoff value of 18.7 U/mL, sRCAS1 showed a good diagnostic performance for MPE. Univariate and multivariate analysis indicated that elevated sRCAS1 levels were an independent predictor of overall survival (OS) and disease-free survival (DFS). Kaplan-Meier survival curves further confirmed that patients with high sRCAS1 have shorter DFS and OS (P = .026 and P = .032, respectively).

Conclusion: In conclusion, measurement of sRCAS1 might be a useful diagnostic and prognostic marker for MPE.
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http://dx.doi.org/10.1111/crj.12527DOI Listing
January 2018

Producing more grain with lower environmental costs.

Nature 2014 Oct 3;514(7523):486-9. Epub 2014 Sep 3.

College of Resources &Environmental Sciences, China Agricultural University, Beijing 100193, China.

Agriculture faces great challenges to ensure global food security by increasing yields while reducing environmental costs. Here we address this challenge by conducting a total of 153 site-year field experiments covering the main agro-ecological areas for rice, wheat and maize production in China. A set of integrated soil-crop system management practices based on a modern understanding of crop ecophysiology and soil biogeochemistry increases average yields for rice, wheat and maize from 7.2 million grams per hectare (Mg ha(-1)), 7.2 Mg ha(-1) and 10.5 Mg ha(-1) to 8.5 Mg ha(-1), 8.9 Mg ha(-1) and 14.2 Mg ha(-1), respectively, without any increase in nitrogen fertilizer. Model simulation and life-cycle assessment show that reactive nitrogen losses and greenhouse gas emissions are reduced substantially by integrated soil-crop system management. If farmers in China could achieve average grain yields equivalent to 80% of this treatment by 2030, over the same planting area as in 2012, total production of rice, wheat and maize in China would be more than enough to meet the demand for direct human consumption and a substantially increased demand for animal feed, while decreasing the environmental costs of intensive agriculture.
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http://dx.doi.org/10.1038/nature13609DOI Listing
October 2014
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