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An overview of the use of plastic-film mulching in China to increase crop yield and water-use efficiency

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National Science Review 2020年第10期7卷 1523-1526页

作者： Dongbao Sun Haigang Li Enli Wang Wenqing He Weiping Hao Changrong Yan Yuzhong Li Xurong Mei Yanqing Zhang Zhanxiang Sun Zhikuan Jia Huaiping Zhou Tinglu Fan Xucheng Zhang Qin Liu Fengju Wang Chaochun Zhang Jianbo Shen Qingsuo Wang Fusuo Zhang centre for resources Environment and Food Security China Agricultural University Key Laboratory of Dryland Agriculture of Ministry of Education Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences CSIRO Agriculture Flagship Inner Mongolia key laboratory of soil quality and nutrient resources Key laboratory of grassland resource (IMAU) Ministry of EducationCollege of Grassland Resources and EnvironmentInner Mongolia Agricultural University Chinese Academy of agricultural Sciences Liaoning Academy of agricultural Sciences College of Agronomy (Academy of agricultural Sciences) Northwest A & F University Institute of agricultural environment and Resource Shanxi Academy of Agricultural Sciences Institute of Dryland agricultural Research Gansu Academy of Agricultural Sciences Institute of Crop Science Chinese Academy of Agricultural Sciences

Since 1990, crop yields have stagnated in many parts of the world, posing a significant challenge to global food security [1].As such, innovative solutions are needed to increase the resource-use efficiency of cropping systems to produce more grains per unit area. In China, which is home to one-fifth of the global population,

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Effects of flooding stress on the photosynthetic apparatus of leaves of two Physocarpus cultivars

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Journal of Forestry Research 2018年第4期29卷 1041-1051页

作者： Huihui Zhang Peng Feng Wei Yang Xin Sui Xin Li Wei Li Rongtao Zhang Siyu Gu Nan Xu College of resources and environment Northeast Agricultural University College of Life Science Northeast Agricultural University Natural resources and Ecology Institute Heilongjiang Academy of Sciences

We applied under pot-culture conditions and the double-casing pot method to study the characteristics of photosynthetic gas exchange and chlorophyll fluorescence in the leaves of Physocarpus amurensis Maxim （PA） and Physocarpus opulifolius under flooding stress. Our results indicate a significantly higher flooding tolerance of P. opulifolius compared to P. amurensis. Especially in P. amurensis, the limitation of non-stomatal factors played a major role in the advanced stages of flooding stress, observed as a rapid increase of the intercellular C02 con- centration （Ci） and a decrease of the stomatal limitation value （Ls）. The maximal PSII photochemical efficiencies （Fv/Fm） and actual photochemical efficiency （60PSU） in the leaves of P. opulifolius were extent of decrease during the than in P. amurensis. In significantly higher, and the flooding process was smaller addition, the non-chemical quenching （NPQ） in the leaves of P. opulifolius significandy increased from the 10th day under flooding stress, while the variation of NPQ in the leaves of P. amurensis was much smaller. This indicates that the leaves of P. opulifolius had not only higher PSII photochemical activity, but also improved tolerance to flooding stress, which may be caused by its ability to dissipate excess excitation energy by starting NPQ. At the 16th day under flooding stress, the PLABS significantly decreased with greater extent of decrease than Fv/Fm in the leaves of both Physocarpus, but the decreasing extent of PIABS in P. opulifolius was significantly smaller than in P. amurensis. In the 16th day under flooding stress, the fluorescence at J and I point （VJ and V1） in P. amurensis were significantly higher, and the extent of increase in VJ was greater than V1. However, the variations of VJ and V1 in the leaves of P. opulifolius were smaller, suggesting that the damage sites of flooding stress to PSII in the leaves of P. amurensis were mainly located in the electron transport process from QA at th

关键词： Physocarpus amurensis Maxim Physocarpusopulifolius Photosynthesis capacity Chlorophyll fluorescence characteristics

Long-Term Manure Amendments Enhance Soil Aggregation and Carbon Saturation of Stable Pools in North China Plain

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Journal of Integrative Agriculture 2014年第10期13卷 2276-2285页

作者： DU Zhang-liu WU Wen-liang ZHANG Qing-zhong GUO Yan-bin MENG Fan-qiao Key Laboratory of agricultural environment Ministry of Agriculture/Agricultural Clear Watershed GroupInstitute of Environment and Sustainable Development in AgricultureChinese Academy of Agricultural Sciences College of resources and environmental Sciences China Agricultural University

Organic amendment is considered as an effective way to increase soil organic carbon （SOC） stock in croplands. To better understand its potential for SOC sequestration, whether SOC saturation could be observed in an intensive agricultural ecosystem receiving long-term composted manure were examined. Different SOC pools were isolated by physical fractionation techniques ofa Cambisol soil under a long-term manure experiment with wheat-maize cropping in North China Plain. A field experiment was initiated in 1993, with 6 treatments including control （i.e., without fertilization）, chemical fertilizer only, low rate of traditional composted manure （7.5 t ha-h）, high rate of traditional composted manure （15 t ha-~）, low rate ofbio-composted manure （7.5 t ha-h） and high rate of bio-composted manure （15 t ha-h）. The results showed that consecutive （for up to 20 years） composted manure amendments significantly improved soil macro-aggregation, aggregate associated SOC concentration, and soil structure stability. In detail, SOC concentration in the sand-sized fraction （〉53 ~tm） continued to increase with manure application rate, while the silt （2-53 ***） and clay （〈2 ~tm） particles showed no further increase with greater C inputs, exhibiting the C saturation. Further physical separation of small macro-aggregates （250-2 000 tam） into subpools showed that the non-protected coarse particulate organic matter （cPOM, 〉250 pro） was the fraction in which SOC continued to increase with increasing manure application rate. In contrast, the chemical and physical protected C pools （i.e., micro-aggregates and silt-clay occluded in the small macro- aggregates） exhibited no additional C sequestration when the manure application rate was increased. It can be concluded that repeated manure amendments can increase soil macro-aggregation and lead to the increase in relatively stable C pools, showing hierarchical saturation behavior in the intensive cropping system of North China Plain.

关键词： composted manure soil aggregates soil organic carbon carbon saturation

Variation of Bioaccumulation Ability of 2,2',4,4'-Tetrabromodiphenyl Ether by Marine Diatom Skeletonema costatum Under Different N:P Ratios

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Journal of Ocean University of China 2014年第3期13卷 523-530页

作者： CHAI Chao GE Wei YIN Xundong College of resources and environment Qingdao Agricultural University College of Life Sciences Qingdao Agricultural University

The growth, biochemical content and bioaccumulation quantity of 2,2',4,4'-tetrabromodiphenyl ether(BDE-47) in Skeletonema costatum were studied under different N:P ratios(1, 4, 16, 64 and 128). All cellular biochemical contents of S. costatum presented decreasing trend over cultivation time. At early stage of cultivation, the cellular protein, carbohydrate and lipid in S. costatum presented higher values in treatments of N:P=4 and 16. However, they were lower in these treatments at the late stage, but higher in treatments N:P=1 and 128. Similarly, BDE-47 levels per cell of S. costatum were higher in treatments of N:P=4 and 16 at early stage of cultivation, which were 3.8 and 3.7 ng(106 cells)-1, respectively. At the middle stage of cultivation, the BDE-47 level per S. costatum cell lowered; and it further reduced in the treatments of N:P=4 and 16 at the late stage with the values 0.6 and 0.5 ng(106 cells)-1, respectively. However, it rose in N:P=128, reaching up to 2.3 ng(106 cells)-1. Compared with BDE-47 per cell, BDE-47 per algal volume under different N:P ratios did not present obvious difference. The quantity BDE-47 accumulated per cell of S. costatum was positively correlated with protein, carbohydrate and lipid per cell; meanwhile, the BDE-47 per volume had a positive correlation with biochemical content per volume. The variation of bioaccumulation ability of BDE-47 in S. costatum can be explained by biochemical changes due to N:P ratios.

关键词： N:P ratio bioaccumulation polybrominated diphenyl ethers microalgae nutrient

Nitrogen release characteristics of polyethylene-coated controlled-release fertilizers and their dependence on membrane pore structure

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Particuology 2018年第1期16卷 158-164页

作者： Xiangdong Yang Rongfeng Jiang Yangzheng Lin Yanting Li Juan Li Bingqiang Zhao Key Laboratory of Plant Nutrition and Fertilizer Ministry of Agricultureflnstitute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China College of resources and environmental Sciences Centre for Resources Environment and Food Security China Agricultural University Beijing 100193 China Geophysical Laboratory Carnegie Institution of Washington Washington DC 20015 USA

In this study, controlled-release fertilizers （CRFs） with five different nitrogen release periods were pre- pared by coating large urea particles with polyethylene （PE） membranes under various experimental conditions. The preliminary and differential solubility rates, release periods, and membrane pore sizes of the obtained CRFs were measured using water immersion, scanning electron microscopy, and mercury porosimetry. For all CRF samples, the median pore diameters of the membranes were equal to 4.5-5.3 nm and pores with sizes smaller than 10 nm accounted for 86-96% of the total pore surface area. The obtained pore diameter distributions differed for the five studied types of CRF, having release periods of 1,2, 4, 6, and 8 months. Thus, for the CRFs with a 1-month release period, the maximum pore diameter reached a magnitude of 4000 nm, while this value did not exceed 30 nm for the CRFs with a release period of 8 months. Hence, we have established a relationship between the release period of CRFs and their effective maximum pore sizes.

关键词： Controlled-release fertilizer Nutrient release period Membrane pore structure Mercury porosimetryPore size

Characterization of summer PM_(2.5) aerosols from four forest areas in Sichuan,SW China

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Particuology 2015年第3期13卷 94-103页

作者： Hengqin Mo Li Li Wei Lai Min Zhao Jinguo Pu Yi Zhou Shihuai Deng Rural environment Protection Engineering & Technology Center of Sichuan Province College of Resources and EnvironmentSichuan Agricultural University Meishan environmental Monitoring Center

Aerosol samples were collected over 24 and 12 h to represent day/night aerosol characteristics in forest areas at Ya＇an Baima Spring Scenic Area （BM）, Panzhihua Cycas National Nature Reserve （PZ）, Gongga Mountain National Nature Reserve （GG）, and Wolong National Nature Reserve （WL）, during the summers of 2010-2012. Mass and chemical component concentrations, including organic carbon, elemental car- bon, and inorganic ions （F , C1 , NO2-, NO3-, SO42-, C2042-, PO43-, K＋, Na＋, Ca2＋, Mg2＋, and NH4＋）, of PM2.5 aerosols were measured. The average PM2.5 concentrations for 24 h were 72.42, 104.89, 20.55, and 29.19 p,g/m3 at BM, PZ, GG, and WL, respectively. Organic matter accounted for 38.0-49.3%, while ele- mental carbon accounted for 2.0-5.7% of PM2.s mass. The sum concentrations of 5042-, NH4＋, and NO3- accounted for 23.0%, 17.4%, 22.1%, and 30.5% of PM2.s mass at BM, PZ, GG, and WL, respectively. Soil dust was also an important source of PM2.s, accounting for 6.3%, 17.0%, 10.4%, and 19.1% of PM2.s mass at BM, PZ, GG, and WL, respectively. These reconstructed masses accounted for 75.9-102.0% of PM2.5 mass from the four forest areas of SW China.

关键词： PM2.5Forest areasMass closureSouthwest China

CH_4 Oxidation Potentials of Diferent Land Uses in Three Gorges Reservoir Area of Central Subtropical China

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Pedosphere 2013年第5期23卷 609-619页

作者： J. IQBAL LIN Shan HU Rong-Gui ZHAO Jin-Song College of resources and environment Huazhong Agricultural University Department of Agronomy Iowa State University

To compare the CH4 oxidation potential among different land uses and seasons, and to observe its response to monsoon precipi- tation pattern and carbon and nitrogen parameters, a one-year study was conducted for different land uses （vegetable field, tilled and non-tilled orchard, upland crops and pine forest） in central subtropical China. Results showed significant differences in CH4 oxidation potential among different land uses （ranging from -3.08 to 0.36 kg CH4 ha-1 year-l）. Upland with corn-peanut-sweet potato rotation showed the highest CH4 emission, while pine forest showed the highest CH4 oxidation potential among all land uses. Non-tilled citrus orchard （-0.72 ~ 0.08 kg CHa ha-1 year-1） absorbed two times more CH4 than tilled citrus orchard （-0.38 ~ 0.06 kg CH4 ha-1 year-l）. Irrespective of different vegetation, inorganic N fertilizer application significantly influenced CH4 fluxes across the sites （R2 ： 0.86, P -- 0.002）. Water-filled pore space, soil microbial biomass carbon, and dissolved nitrogen showed significant effects across different land uses （31% to 38% of variability） in one linear regression model. However, their cumulative interaction was significant for pine forest only, which might be attributed to undisturbed microbial communities legitimately responding to other variables, leading to net CH4 oxidation in the soil. These results suggested that i） natural soil condition tended to create win-win situation for CH4 oxidation, and agricultural activities could disrupt the oxidation potentials of the soils; and ii） specific management practices including but not limiting to efficient fertilizer application and utilization, water use efficiency, and less soil disruption might be required to increase the CH4 uptake from the soil.

关键词： CH4 emission CH4 fluxes dissolved nitrogen microbial biomass water-filled pore space

Long-Term Fertilization Effect on Fertility of Salt-Affected Soils

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Pedosphere 2005年第5期15卷 669-675页

作者： NIU Ling-An HAO Jin-Min DING Zhong-Yi LI Xin-Bo NIU Xin-Sheng ZHANG Bao-Zhong College of resources and environment China Agricultural University Beijing 100094 （China）. Handan agricultural School Handan 056001 （China）

The long-term effects of annual fertilizer applications on the fertility of salt-affected soils under the rotation system of wheat （Triticum aestivum L.） and maize （Zea mays L.） are not well documented. In 1984, research plots were established to test the effects of annual applications of different rates of nitrogen （N） and phosphorus （P） fertilizers on the fertility of a salt-affected soil （Typic Ustochrept） at the Quzhou Experimental Station, Quzhou County, Hebei Province, China. In October 2001, composite soil samples （0-20 and 20 40 cm） were collected from each plot and analyzed for soil fertility indices. Seventeen years of N and P fertilizer applications increased the soil organic matter （SOM） in the surface layer. With combined N, 270 （N1） and 540 （N2） kg N ha^-1 year^-1, and P, 67.5 （P1） and 135 （P2） kg P205 ha^-1 year^-1, fertilizer applications, total soil N mostly significantly decreased （P〈0.05）. Soil total P in the 0-20 cm layer of the P2 treatment significantly （P （0.05） increased as compared to those of the other treatments. Rapidly available P （RP） in the 0-20 cm layer of the N1P2 treatment was significantly higher than those in the other treatments except the P2 treatment; and RP in the 0-20 cm layer of the P2 treatment significantly increased as compared to those of the other treatments except the P1 and N1P2 treatments. RP in the subsurface soil layer （20-40 cm） of the P2 treatment （4.2 mg P kg^-1） was significantly （P〈0.05） higher than those in the other treatments. Nevertheless, long-term N fertilization did not significantly increase the alkali-hydrolyzable N in the soil. However, in the salt-affected surface soils the application of combined N and P fertilizers over 17 years significantly （P〈0.05） decreased rapidly available potassium （K）. The results suggested that while under long-term fertilizer applications some soil fertility parameters could be maintained or enhanced, careful monitoring of soil fertility was necessary as other nutrients

关键词： long-term fertilization maize salt-affected soil soil fertility wheat

A spatial frequency/spectral indicator-driven model for estimating cultivated land quality using the gradient boosting decision tree and genetic algorithm-back propagation neural network

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International Soil and Water Conservation Research 2022年第4期10卷 635-648页

作者： Ziqing Xia Yiping Peng Chenjie Lin Ya Wen Huiming Liu Zhenhua Liu College of Natural resources and environment South China Agricultural UniversityGuangzhou510642China

Cultivated land quality(CLQ)is related to national food *** and high-precision monitoring of CLQ is crucial for the sustainable development of ***,current satellite image-based evaluation methods that only consider the crop's spatial spectrum characteristics in the key growth stages cannot accurately estimate *** study proposes a new method based on time-series spectral data of crop growth to improve the accuracy of CLQ *** study was conducted in the Conghua District of Guangzhou,Guangdong Province,*** results showed that seven spectral indicators were determined as the optimal indicators based on the gradient boosting decision tree(GBDT)and variance inflation factor(VIF).And the genetic algorithm-back propagation neural network(GA-BPNN)model provided more accurate CLQ estimates than the partial least squares regression(PLSR)model,indicating a nonlinear relationship between CLQ and the *** addition,the GA-BPNN model with a normalized root mean square error(NRMSE)of 9.91%demonstrates the excellent potential for mapping CLQ over large *** model based on the seven optimal indicators of crop phenology provided higher accuracy than the GA-BPNN model based on the normalized difference vegetation index(NDVI)indicators in the spatial domain,significantly decreasing the NRMSE of the CLQ estimates by 3.17%.This further implied that the spectral indicators in the spatial frequency domain can improve the accuracy of estimating CLQ.

关键词： Cultivated land quality Time-series spectral data Spectral indicators Spatial frequency domain Conghua district