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光温因子驱动的园艺作物叶龄模型模拟精度比较

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浙江农业学报 2024年第6期36卷 1368-1378页

作者：程陈董朝阳郑生宏周宇博钟宁李文明朱阳春丁枫华冯利平黎贞发丽水学院生态学院浙江丽水323000 中国农业大学资源与环境学院北京100193 天津市气候中心天津300074 丽水市农林科学研究院茶叶研究所浙江丽水323000 丽水市气象局浙江丽水323050

为了提高光温因子驱动的园艺作物通用性叶龄模拟模型的模拟精度,以黄瓜、芹菜、菠菜、小香芹、郁金香和茶叶为供试材料,进行了7年(2016—2022年)的分期播种试验,依据作物生长发育与关键气象因子(辐射和温度)的关系,采用4类建模方法(温... 详细信息

为了提高光温因子驱动的园艺作物通用性叶龄模拟模型的模拟精度,以黄瓜、芹菜、菠菜、小香芹、郁金香和茶叶为供试材料,进行了7年(2016—2022年)的分期播种试验,依据作物生长发育与关键气象因子(辐射和温度)的关系,采用4类建模方法(温差法、积温法、生理发育时间法和辐热积法)构建了园艺作物叶龄模拟模型,并以6种方式(平均值、最值均值、中值、逐步回归、BP神经网络和Elman神经网络)和2种集成逻辑(直接和分步)集成模拟结果,最终优化模型模拟精度。结果表明:1)2种集成逻辑下模型模拟精度均较高,且分步集成逻辑优于直接集成逻辑,平均绝对误差(mean absolute error,MAE)差值为0.31 d,平均相对误差(mean relative error,MRE)差值为0.33%,均方根误差(root mean square error,RMSE)差值为0.40 d,归一化均方根误差(normalized root mean square error,NRMSE)差值为0.46%;2)2种集成逻辑下模型最优时间尺度为逐时尺度,最优作物类型为茶叶,最优建模方法为Elman神经网络集成模拟模型。研究结果可为园艺作物智慧生产管理和可视化提供理论依据和技术支撑。

关键词：园艺作物叶龄模型逐步回归神经网络算法集成逻辑

Variation of Zn content in soils under different land-use types in the Hetao oasis,Inner Mongolia of China

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Journal of Arid Land 2016年第6期8卷 861-870页

作者： zhu yangchun ZHAO Xueyong LIAN Jie CHEN Min Naiman Desertification Research Station/Urat Desert-grassland Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Understanding the status and distribution of the micronutrient Zn in soils is important for managing plant growth and preventing soil pollution for agricultural irrigation systems in arid and semi-arid regions. In this study, a total of 195 soil samples from five soil layers （0-20, 20-40, 40-60, 60-80 and 80-100 cm） in the three land-use types （wasteland, forestland and cropland） after long-term agricultural fertilization and irrigation with Yellow River water were collected in the middle of the Hetao oasis, i.e. the Yongji irrigation sub-oasis. We analyzed the vertical and spatial distributions of Zn content and its relationship with soil properties to determine whether differences of Zn content existed in the soil profiles. The results revealed that the mean content of Zn was 107 mg/kg, 1.9 times higher than the background value （55.7 mg/kg） of the Hetao oasis and much lower than the secondary standard value （300 mg/kg） of the Chinese Environmental Quality Standard for Soils when pH〉7.5. Soil Zn contents were not significantly different and the coefficients of variation of Zn contents were less than 50% in the five soil layers. Soil Zn content was similar from southern to northern parts but increased from western to eastern parts in the sub-oasis. Soil Zn contents did not differ significantly among the three land-use types, but soil total nitrogen （TN） contents were significantly higher in the agriculturally managed forestland and cropland than in the wasteland （P〈0.05）. Zn was significantly and positively correlated with TN （F=36.6, P〈0.001）. The use of fertilizers may increase the content of Zn in soils, but flooding irrigation may minimize the differences in the spatial distribution of soil Zn content in the whole sub-oasis. This research is of important value for soil pollution control and sustainable land use management in arid and semi-arid regions.

关键词： fertilizer land-use type spatial distribution soil profile soil property

CAS-ESM2.0 Successfully Reproduces Historical Atmospheric CO_(2) in a Coupled Carbon−Climate Simulation

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Advances in Atmospheric Sciences 2024年第4期41卷 572-580页

作者： Jiawen zhu Juanxiong HE Duoying JI yangchun LI He ZHANG Minghua ZHANG Xiaodong ZENG Kece FEI Jiangbo JIN International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044China College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China School of Marine and Atmospheric Sciences Stony Brook UniversityNY 11790USA University of Chinese Academy of Sciences Beijing 100049China

The atmospheric carbon dioxide(CO_(2))concentration has been increasing rapidly since the Industrial Revolution,which has led to unequivocal global warming and crucial environmental *** is extremely important to investigate the interactions among atmospheric CO_(2),the physical climate system,and the carbon cycle of the underlying surface for a better understanding of the Earth *** system models are widely used to investigate these interactions via coupled carbon-climate *** Chinese Academy of Sciences Earth System Model version 2(CAS-ESM2.0)has successfully fixed a two-way coupling of atmospheric CO_(2)with the climate and carbon cycle on land and in the *** CAS-ESM2.0,we conducted a coupled carbon-climate simulation by following the CMIP6 proposal of a historical emissions-driven *** paper examines the modeled CO_(2)by comparison with observed CO_(2)at the sites of Mauna Loa and Barrow,and the Greenhouse Gases Observing Satellite(GOSAT)CO_(2)*** results showed that CAS-ESM2.0 agrees very well with observations in reproducing the increasing trend of annual CO_(2)during the period 1850-2014,and in capturing the seasonal cycle of CO_(2)at the two baseline sites,as well as over northern high *** agreements illustrate a good ability of CAS-ESM2.0 in simulating carbon-climate interactions,even though uncertainties remain in the processes *** paper reports an important stage of the development of CAS-ESM with the coupling of carbon and climate,which will provide significant scientific support for climate research and China’s goal of carbon neutrality.

关键词： CAS-ESM atmospheric CO_(2) coupled carbon-climate simulation emissions-driven CMIP6 experiment

Floral traits and pollination system of Zygophyllum xanthoxylum in the managed and wild populations in an arid region of Northwest China

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Journal of Arid Land 2015年第4期7卷 488-500页

作者： CHEN Min ZHAO Xueyong ZUO Xiao'an LIAN Jie zhu yangchun Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences

Zygophyllum xanthoxylum, which belongs to Sarcozygium of Zygophyllaceae, is one of the ecologically important species in Northwest China. In order to understand the pollination system of Z. xanthoxylum, we investigated the following characteristics of this species in the Urat Desert-grassland Research Station in western Inner Mongolia of China： flowering dynamics, pollen viability, pollen limitation, floral visitors and breeding system. The results showed that the flowering period and flowering peak were different between the wild and managed popula- tions, being longer in the managed population. Z. xanthoxylum was pollen-limited, and pollen limitation was more intense in the wild population than in the managed population. Chalicodoma deserticola （Hymenoptera） was found to be the most frequent pollinator in the wild population, while Anthophora fulvitarsis （Hymenoptera） was the most frequent and effective visitor in the managed population. Out-crossing was dominant in the breeding system and self-pollination just played an assistant role to assure the reproduction of Z. xanthoxylum.

关键词： Zygophyllum xanthoxylum pollination pollen limitation floral visitor fruit set seed set breeding system

Accumulation and potential sources of heavy metals in soils of the Hetao area,Inner Mongolia,China

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Pedosphere 2020年第2期30卷 244-252页

作者： yangchun zhu Lijin WANG Xueyong ZHAO Jie LIAN Zhenhua ZHANG Ecology Institute Lishui UniversityLishui 323000China Institute of Agricultural Resource and Environmental Sciences Jiangsu Academy of Agricultural SciencesNanjing 210014China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China

Soil contamination by heavy metals is a problem in agricultural irrigation *** assess the accumulation and sources of heavy metals in the Yongji irrigation district of the Hetao area,Inner Mongolia,China,195 soil samples from 39 sites(0–100 cm)were collected,and Zn,Cu,Pb,Cr,and Cd concentrations were *** mean concentrations were 107.17,32.48,12.31,53.53,and 0.22 mg kg-1,respectively,with no significant differences between soil depths(P>0.05).Concentrations of Zn,Cu,and Cd were higher than the background levels,with moderate accumulation;the contamination factor(CF)values were 1.9,1.7,and 1.9,respectively,and the geoaccumulation index(Igeo)was>*** of Pb and Cr were lower than,or close to,the background levels(CF<1,Igeo<0),indicating that they originated from a natural *** monomial potential ecological risk index(Eri)for Zn,Cu,Pb,and Cr was low;Eri for Cd was 55.73,implying a moderate *** grade of potential ecological risk index of the five heavy metals(RI)was low,declining from south to *** studied soils were contaminated with Zn,Cu,and Cd;principal component(PC)analysis implicated the enrichment of Cd and partial Cu(high loading in PC 2)was related to agricultural activities;Zn and partial Cu,closely associated with PC 3,may have originated from irrigation water from the Yellow *** agricultural development should focus on fertilizer and pesticide application and the quality of irrigation water.

关键词： agricultural activity contamination factor geoaccumulation index potential ecological risk principal component analysis soil layer spatial distribution

Artificial root exudates and soil organic carbon mineralization in a degraded sandy grassland in northern China

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Journal of Arid Land 2014年第4期6卷 423-431页

作者： YongQing LUO XueYong ZHAO Olof ANDRéN yangchun zhu WenDa HUANG Naiman Desertification and Farmland Research Station of the Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences Bjorklundavagen 3

Plant root exudates contain various organic and inorganic components that include glucose, citric and oxalic acid. These components affect rhizosphere microbial and microfaunal activities, but the mechanisms are not fully known. Studies concerned from degraded grassland ecosystems with low soil carbon（C） contents are rare, in spite of the global distribution of grasslands in need of restoration. All these have a high potential for carbon sequestration, with a reduced carbon content due to overutilization. An exudate component that rapidly decomposes will increase soil respiration and CO2 emission, while a component that reduces decomposition of native soil carbon can reduce CO2 emission and actually help sequestering carbon in soil. Therefore, to investigate root exudate effects on rhizosphere activity, citric acid, glucose and oxalic acid（0.6 g C/kg dry soil） were added to soils from three biotopes（grassland, fixed dune and mobile dune） located in Naiman, Horqin Sandy Land, Inner Mongolia, China） and subjected to a 24-day incubation experiment together with a control. The soils were also analyzed for general soil properties. The results show that total respiration without exudate addition was highest in grassland soil, intermediate in fixed dune and lowest in mobile dune soil. However, the proportion of native soil carbon mineralized was highest in mobile dune soil, reflecting the low C/N ratio found there. The exudate effects on CO2-C emissions and other variables differed somewhat between biotopes, but total respiration（including that from the added substrates） was significantly increased in all combinations compared with the control, except for oxalic acid addition to mobile dune soil, which reduced CO2-C emissions from native soil carbon. A small but statistically significant increase in pH by the exudate additions in grassland and fixed dune soil was observed, but there was a major decrease from acid additions to mobile dune soil. In contrast, electrical condu

关键词： artificial root exudates carbon mineralization pH variation deteriorated grassland ecosystem Inner Mongolia

Characteristics of high arsenic groundwater in Hetao Basin,Inner Mongolia,northern China

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Research in Cold and Arid Regions 2015年第1期7卷 104-110页

作者： yangchun zhu XueYong Zhao Min Chen YongQing Luo Xin Zhou Naiman Desertification Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

It is well known that the Hetao Basin is one of the most seriously arsenic-affected groundwater areas in China. In order to understand the characteristics of high arsenic （As） groundwater in the Basin, a brief overview of arsenic in groundwater follows. High arsenic in the Basin commonly occurs in shallow groundwater and the total arsenic concentrations range from 0.58 to 572 μg/L （average 99.73 μg/L）, exceeding the maximum mandated value of 10 μg/L for drinking water in China; As（III） is the predominant species. The regional distribution pattern of arsenic in the groundwater increases from south/southeast to north/northwest. Hangjinhouqi and Wuyuan counties are considered as the most seriously affected areas, with high incidences of endemic arsenicosie diseases in the Hetao Basin. High groundwater arsenic correlates with the increase of well depth. Previous studies proposed that groundwater arsenic in the Basin is mainly originated from desorption of some natural solid materials in the sediments, under reducing condition. Generally, reducing condition is believed to be the primary factor for arsenic releasing from the sediment to groundwater in the region. Under inorganic Or bacterial processes, Fe2O3 changes to FeS and arsenic adsorbed to Fe（OH）3 dissolves into groundwater, and As（V） is re- duced to As（W）. Besides, reducing environments, groundwater hydraulic gradients, organic matter, pH, evapotranspiration, and soil texture are presumed to be the predominant factors that control arsenic mobilization.

关键词： spatial distributions source reducing condition influencing factor

浙西南镉高背景值耕地的水稻安全利用技术研究

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丽水学院学报 2023年第2期45卷 71-76页

作者：陈振华朱阳春浙江农林大学环境与资源学院浙江杭州311300 景宁县农业农村局浙江景宁323500 丽水学院生态学院浙江丽水323000

我国土壤镉(Cd)污染区与水稻种植区在空间分布上基本吻合,水稻属于易积累Cd的作物之一。浙江省西南部分区域,由于母质原因,出现地质性重金属高背景值现象。本研究开展了中轻度Cd污染耕地安全利用的核心技术田间试验,包括低积累水稻品种... 详细信息

我国土壤镉(Cd)污染区与水稻种植区在空间分布上基本吻合,水稻属于易积累Cd的作物之一。浙江省西南部分区域,由于母质原因,出现地质性重金属高背景值现象。本研究开展了中轻度Cd污染耕地安全利用的核心技术田间试验,包括低积累水稻品种筛选、钝化修复材料筛选、农艺调控措施三项技术。结果表明:采用水稻甬优1540+石灰100 kg/亩+全生育期淹水+有机肥1150 kg/亩的安全利用集成技术模式能最大限度地降低水稻籽粒中的Cd含量,可以作为该区域镉高背景值耕地的水稻安全利用技术集成模式并推广应用。

关键词：耕地水稻镉污染安全利用

基于R600/R290混合制冷剂的立式冷冻箱的降温能力试验研究

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制冷与空调 2022年第1期22卷 43-46页

作者：刘悦超朱阳春黄玉杰澳柯玛股份有限公司

为优化以混合制冷剂为工质的立式冷冻箱制冷系统降温能力,对使用R600/R290混合制冷剂的立式冷冻箱在32℃环境温度下进行降温能力试验,研究混合制冷剂充注量、制冷剂各组分配比、毛细管流量及风机转速对其性能的影响。结果表明:混合制冷... 详细信息

为优化以混合制冷剂为工质的立式冷冻箱制冷系统降温能力,对使用R600/R290混合制冷剂的立式冷冻箱在32℃环境温度下进行降温能力试验,研究混合制冷剂充注量、制冷剂各组分配比、毛细管流量及风机转速对其性能的影响。结果表明:混合制冷剂充注量过大会削弱制冷系统降温能力,并使压缩机功率增加;增大毛细管流量、风机转速及混合制冷剂中R290的占比可以提高制冷系统降温能力,制冷系统拉温深度下降0.7~3.3℃,但同时会增大制冷系统运行功率;毛细管流量为5 L/min,制冷剂充注量为50 g,R600与R290质量比为7:3是满足设计要求的最佳系统配置。

关键词：立式冷冻箱混合制冷剂 R600/R290 降温能力