基于CERES-Maize模型的吉林春玉米遗传参数调试

为了应用CERES-Maize模型模拟吉林春玉米生长发育和产量形成,需要确定主栽春玉米品种的遗传参数。采用晚熟春玉米品种‘吉单159’和‘先玉335’多年田间观测数据和同期气象、土壤等数据进行遗传参数调试,并对模型的模拟效果进行验证。结果表明:2个春玉米品种生育期的模拟值和实测值散点均在1:1线周围。‘吉单159’播种至开花天数和播种至成熟天数RMSE值分别为3.78和10.90。‘先玉335’播种至出苗天数、播种至开花天数和播种至成熟天数RMSE值分别为1.12、3.20和4.85。2个品种春玉米的地上部生物量和叶面积指数的模拟值与实测值均在抽雄期接近,三叶期和七叶期差异最大。‘吉单159’和‘先玉335’产量的RRMSE值分别为4.31%和4.81%。说明CERES-Maize模型对吉林春玉米生育期和产量模拟效果较好,地上部生物量次之,叶面积指数一般。总之,CERES-Maize模型能够应用于吉林省气候变化对春玉米影响的评价。     

丛枝菌根真菌与间作对滇池流域红壤上大豆生长及磷累积的影响

为了探讨玉米/大豆间作体系中不同丛枝菌根真菌(AMF)对大豆生长及磷吸收累积的影响,通过盆栽模拟试验对不同AMF处理[不接种(NM)、接种Glomus mosseae(GM)、接种Glomus etunicatum(GE)]与不同根系分隔方式(不分隔、尼龙网分隔、塑料布分隔)组合进行研究。结果表明,大豆根系侵染率GM一根系不分隔处理最高。与NM处理相比,无论何种根系分隔方式,GM处理均显著增加了大豆的株高及其植株生物量,并明显增加了大豆地上部磷含量及磷吸收量;GE处理也明显增加了大豆植株生物量和株高并显著增加了根系磷吸收量。无论何种AMF处理,大豆根系磷吸收量均以尼龙网分隔处理显著高于塑料布分隔处理,明显高于不分隔处理。所有复合处理中,大豆地上部磷含量和磷吸收量、根系磷吸收效率均是GM一根系塑料布分隔处理最高。可见,在滇池流域玉米/大豆间作种植区通过GM一根系塑料布分隔处理可以有效促进大豆地上部磷的迁移累积,进而改善其生长。     

丛枝菌根真菌根外菌丝对紫色土中的氮素利用状况

摘 要：本研究采用修改后的Hawkins and George（1999）的装置,并以中性紫色土壤为基质模拟自然生长环境,研究根外菌丝对土壤中的氮素的利用状况。结果表明：接种Glomus intraradices发挥了较好的菌根效应,相对不接种处理,普遍提高了玉米地上部和根系的氮、磷营养状况;根外菌丝能扩大根系对氮素的吸收范围,扩大的吸收范围应不小于5cm;而根外菌丝利用的氮素形态主要是无机态的氮。     

磷营养对不同大豆品种生长和磷吸收利用效率的影响

采用液体培养方法,研究了磷素营养对山西省审定的10个有代表性的大豆品种生长和磷吸收利用效率的影响。结果表明,在低磷和高磷条件下,不同大豆品种的株高、主根长、根体积、叶面积和植株干物质量差异达到了显著或极显著水平。在高磷条件下不同大豆品种间植株的磷吸收量差异达到了极显著水平,但在低磷条件下其差异不显著。晋豆11号、晋豆4号和晋豆23号在低磷条件下具有较高的磷利用效率,表明它们适合于低磷土壤种植;晋豆10号和晋豆11号在高磷条件下磷的利用率较高,说明它们适合于磷有效含量高的土壤种植。合理利用大豆品种资源,有利于发挥品种利用磷素的潜力,提高磷的利用效率。     

不同连作年限对大豆根际土壤养分的影响

本试验通过对不同连作年限大豆根际土壤养分的测定,明确了连作对大豆根际土壤养分的影响,研究结果表明,连作处理根际土壤pH值随连作年限增长呈下降趋势,各连作大豆根际土壤中氮、磷、钾、镁、锌、硼、钼、有机质等养分含量均低于正茬,不同连作年限对大豆根际土壤中铁、钙、锰含量的影响未表现出线形规律。     

玉米-大豆轮作及氮肥施用对土壤细菌群落结构的影响

在大豆开花期分别对3个施氮水平下(0、50和100 kg hm^-2)大豆连作(大豆-大豆-大豆)、玉米-大豆轮作I (大豆-玉米-大豆)及玉米-大豆轮作II (玉米-玉米-大豆),应用PCR-DGGE技术研究了玉米-大豆轮作及施氮对土壤细菌群落结构变化的影响。结果表明,随着施氮水平的提高,3种种植方式土壤中细菌群落多样性、丰富度均呈减少趋势。高氮处理(100 kg hm^-2)明显降低了大豆连作、玉米-大豆轮作II根际土壤细菌群落多样性及丰富度,玉米-大豆轮作I根际土壤细菌群落多样性及丰富度略有降低。玉米-大豆轮作I种植方式可减轻氮肥对其根际细菌群落多样性和丰富度的影响,但施氮明显改变了其细菌群落结构。玉米-大豆轮作II中大豆根际土壤细菌群落结构较为稳定,受氮肥影响较小。在3种种植方式的土壤中,分布着酸杆菌门、变形菌门及厚壁菌门细菌,其中前两门菌群占主导地位。     

杨树根际土壤磷吸附特性的研究

对滨海脱盐土壤上11年生1-69杨根际、非根际土壤磷吸附特性进行了研究。结果表明,I-69杨根系活动能抑制根际土壤对磷的吸附,抑制能力与培养溶液起始磷浓度相关,当培养溶液起始磷浓度为30 mg／L时,抑制能力最大,根际、非根际土壤磷吸附量之差为-15．57 mg／kg;I-69杨根际、非根际土壤磷恒温吸附数据都能很好地用一元 Langmuir方程、Freundich方程和Temkin方程拟合,其中一元Langmuir方程拟合最好;根际土壤磷吸附容量参数Xm,k, k1,k2的值明显低于非根际土壤,相关分析表明,它们与土壤有效磷含量呈显著负相关。     

施磷对不同间作体系间作优势与磷肥利用的影响

为了探明施磷水平对不同间作体系产量间作优势和磷肥利用的影响,在河北曲周主要研究了施磷对玉米‖蚕豆、玉米‖大豆和玉米‖油菜3种间作体系土地当量比(LER)、磷吸收量、磷肥吸收效率和磷间作优势的影响。结果表明：玉米‖蚕豆的LER是1.24~1.31,玉米‖油菜的LER是1.20~1.24,玉米‖大豆的LER是1.11~1.15,均大于1,具有明显的间作优势;3个磷水平下,吸磷量表现为玉米‖大豆>玉米‖蚕豆>玉米‖油菜,除玉米‖油菜间作体系外,比单作玉米分别高21.5%%~40.2%和13.3%~22.9%,且均随着施磷量的增加而增加,但增加幅度降低;3种间作体系均具有明显的磷间作优势,除玉米‖大豆间作体系外,施磷后均降低;磷肥吸收效率除玉米‖蚕豆在施磷90 kg/hm²外均低于单作玉米,并且随着施磷量的增加而降低。这表明,通过活化磷能力强的作物与玉米间作可以提高土壤难溶性磷的利用,玉米‖大豆和玉米‖蚕豆比玉米‖油菜效果好,适宜的施磷量为90 kg/hm²。     

长期轮作连作对不同作物土壤磷组分的影响

对长期轮作连作条件下的大豆、玉米、小麦土壤磷组分进行研究,试验结果表明,供试土壤在不施肥情况下,土壤全磷以轮作区降幅最大,而土壤有效磷以小麦连作区降幅最大,土壤磷组分以大豆连作区土壤中的Ca2-P降幅最大;在施有机肥的情况下,土壤全磷以大豆连作区增幅最大,而土壤有效磷以轮作区增幅最小,土壤磷组分以轮作土壤中的Ca2-P增幅最大。     

春玉米春大豆间作种植技术研究

采用回归正交旋转组合设计的方法,选择春玉米间作春大豆的畦幅、春玉米密度、春大豆密度三个农艺因子,布置田间参数试验,通过对试验结果的分析,建立了春玉米间作春大豆的总产、春玉米产量、春大豆产量及净产值的三元二次回归模型。根据建立的模型,进行了因子效应分析,并结合计算机模拟寻优,对春玉米间作春大豆的畦幅及其复合群体结构进行了优化。     

AquaCrop模型在东北黑土区作物产量预测中的应用研究

东北黑土区是我国玉米和大豆生产基地,为了实现利用AquaCrop模型优化管理和预测产量,本文基于作物小区田间试验和大田观测数据,采用OAT(one factor at a time)法分析了该模型参数的敏感性,率定了敏感性高的参数,并对率定后的模型进行了验证。结果表明:玉米和大豆产量均对影响经济产量的收获指数十分敏感,二者虽然对冠层和根系生长参数都敏感,但有所差异:玉米对冠层衰减系数(canopy decline coefficient,CDC)更为敏感,而大豆则对限制冠层伸展的水分胁迫系数曲线的形状因子(shape factor for water stress coefficient for canopy expansion,Pexshp)更为敏感;玉米因根系深对最大有效根深(maximum effective rooting depth,Zx)更敏感,大豆因根系浅对根区根系伸展曲线的形状因子(shape factor describing root zone expansion,Rexshp)更敏感。由于玉米需水量大,对冠层形成和枯萎前的作物系数(crop coefficient before canopy formation and senescence,KcTr,x)和归一化水分生产力(normalized water productivity,WP*)很敏感,大豆则是一般敏感。率定后模型模拟玉米产量与实测产量的回归系数由0.34提升至0.89,模拟大豆产量与实测产量的回归系数由0.80提升至0.88。进一步用大田实测产量的验证结果表明:预测的玉米与大豆产量与实测产量间回归方程的决定系数(coefficient of determination,R2)分别为0.775和0.779,均方根误差(root mean square error,RMSE)分别为1.076 t hm^–2和0.299 t hm^–2,标准均方根误差(normalized root mean square error,NRMSE)分别为0.097和0.178,模拟效率(model efficiency,ME)分别为0.747和0.730,率定后的AquaCrop模型能较精准地模拟东北黑土区玉米和大豆产量,可用于产量预测或优化管理。     

AquaCrop模型在东北黑土区作物产量预测中的应用研究

Northeast black soil area is the production area of maize and soybean in China. In order to optimize the agricultural management and forecast crop yield with AquaCrop model, we use OAT (one factor at a time) method to analyze the sensitivity of the model parameters based on the experiment and field observation data, and to validate the model after calibrated the high sensitivity parameters. The results of sensitivity analysis showed that the yields of maize and soybean were both extremely sensitive to the reference harvest index (HI₀) and the parameters of canopy growth and root growth. The difference was that maize was more sensitive to the canopy decline coefficient (CDC), while soybean was more sensitive to the shape factor for water stress coefficient for canopy expansion (Pexshp). Maize was more sensitive to the maximum effective rooting depth (Z_x) because of its deep root, while soybean was more sensitive to the shape factor describing root zone expansion (Rexshp) because of its short roots. Maize was extremely sensitive to the crop coefficient before canopy formation and senescence (Kc_Tr,x) and the normalized water productivity (WP^*) due to the large water demand, while soybean was only generally sensitive. After calibrated the high sensitivity parameters with experiment data, the regression coefficient of simulated yield and measured yield of maize increased from 0.34 to 0.89, and the regression coefficient of simulated yield and measured yield of soybean increased from 0.80 to 0.88. Furthermore, the validation results of field observation data indicated that the determination coefficients (R²), the root mean square error (RMSE), the normalized root mean square error (NRMSE) and the model efficiency (ME) of the AquaCrop model of maize and soybean were 0.775 and 0.779, 1.076 t hm^-2 and 0.299 t hm^-2, 0.097 and 0.178, 0.747 and 0.730, respectively. The calibrated AquaCrop model can accurately simulate the yield of corn and soybean in the black soil area of Northeast China, and is useful for yield prediction and optimal management.     

基于磷肥施用深度的夏玉米根层调控提高土壤氮素吸收利用

良好的根系构型能够促进作物高效获取土壤养分。基于磷肥施用深度的根层调控技术可以优化夏玉米根系的时空分布并促进其与土壤水分、养分供应的空间匹配性,为通过玉米根系挖潜实现节肥增效提供理论与技术支撑。本试验以不施磷肥处理为对照(CK),设置距离地表-5 cm (P5)、-10 cm (P10)、-15 cm (P15)和-20 cm (P20)深度施用磷肥处理,分析各处理对夏玉米根系分布、植株生长及产量形成、氮素吸收、积累与转运的影响。结果表明,磷肥适当深施显著促进夏玉米根系生长,根干重、根长密度、根系表面积和根体积均显著增加,整体表现为P15>P10>P20>P5>CK。随着磷肥施用深度的增加,深层玉米根系显著增加。P15和P20处理根干重所占比重,在20～40cm土层分别为12.3%和12.1%;在40～60 cm土层分别为6.7%和6.9%。根系分布深度的增加促进了对土壤氮素的吸收,深施磷肥处理各土层中尤其是20cm以下土层土壤氮素含量显著降低。根系分布的优化同时促进了植株氮素积累与转运, P15处理较P5处理氮素吸收效率、氮积累量、转运量及氮肥偏生产力2年平均...     

Development and Testing of Root Effectiveness Function for Soil Water Uptake

For soil water uptake studies under cropped conditions, root effectiveness for soil water absorption is of great significance. For development of root effectiveness function, information on the age of roots present at any soil depth at any time during the crop growth period is needed. For estimation of root age and root effectiveness function, a methodology has been developed. Wheat crop was used as a test crop. It has been observed that root effectiveness for water uptake remains constant during the early period of root growth and thereafter it decreases exponentially with root age. The application of the proposed root effectiveness function was tested successfully using macroscopic model of soil water dynamics which yielded 7 .83 per cent variation between observed and simulated soil water content on overall basis in the crop root zone for the entire crop growth season.     

设施条件接种丛枝菌根真菌对紫色土上玉米/大豆生长及氮素利用的影响

为了阐明紫色土上接种丛枝菌根真菌（arbuscular mycorrhizal fungus,AMF）和不同间作方式对提高间作玉米（Zea mays L.）、大豆（Glycine max L.）的氮素利用和减少土壤氮残留的贡献。本试验在设施盆栽条件下,采用根系分隔模拟装置研究玉米/大豆间作体系中根系不分隔、尼龙网分隔、塑料膜分隔3种方式和不同AMF处理[不接种AMF（NM）、接种Glomus mosseae（GM）]对玉米、大豆植株生长、氮素累积与利用的影响。研究结果表明：接种GM不同程度提高了间作玉米和大豆根系菌根侵染率、株高、植株生物量及氮含量,而显著降低了玉米和大豆种植土壤的碱解氮含量。其中,GM-根系不分隔处理玉米、大豆的菌根侵染率最高。无论是否接种AMF,大豆生物量和植株氮含量均以根系分隔处理显著高于不分隔处理,而玉米生物量和植株氮含量却刚好相反。此外,GM处理条件下,玉米、大豆根际土壤碱解氮含量均以尼龙网分隔和不分隔处理显著低于塑料膜分隔处理。在所有复合处理中,以GM-根系不分隔处理对玉米生长及氮素累积的促进作用最好;GM-尼龙网分隔处理对大豆生长及氮素累积的促进效果最佳,并更能显著降低玉米、大豆根际土壤的碱解氮残留,可望减轻土壤氮流失而降低氮素流失对地表水体的污染风险。     

腐殖酸及腐殖酸有机肥对玉米养分吸收及肥料利用率的影响

为了促进腐殖酸资源在农业生产上的合理利用,缓解中国有机肥源不足的问题,通过小区试验,研究了不施肥、施化肥、风化煤与化肥配施、腐殖酸有机肥对玉米植株性状、干物质积累、籽粒产量、养分吸收量及肥料利用率的影响。结果表明,不同施肥措施均能显著改善玉米植株生长,促进玉米干物质积累,提高籽粒产量及养分吸收量;风化煤与化肥配施、腐殖酸有机肥较单施化肥显著改善了玉米生长,增加了根重、秸秆重、籽粒产量,提高各部位氮磷含量及氮磷肥的利用率;风化煤与化肥配施、腐殖酸有机肥还能促进植株对钾的吸收,显著提高根系和秸秆中钾含量,对籽粒中钾含量的影响不显著。     

三种霉菌发酵液对作物的促长作用初报

摘要：本文采用盆栽试验的方法研究了三种霉菌发酵液对玉米、大豆生长的影响。结果表明,适宜浓度的三种霉菌发酵液可以显著提高玉米、大豆的株高、根长,干重及叶绿素含量。对作物具有显著的促长作用。     

Performance and sensitivity of the DSSAT crop growth model in simulating maize yield under conservation agriculture

With the practice of conservation agriculture (CA) soil water and nutrient dynamics are modified by the presence of a mulch of crop residues and by reduced or no-tillage. These alterations may have impacts on crop yields. The crop growth model DSSAT (Decision Support Systems for Agrotechnology Transfer) has recently been modified and used to simulate these impacts on crop growth and yield. In this study, we applied DSSAT to a long-term experiment with maize (Zea mays L.) grown under contrasting tillage and residue management practices in Monze, Southern Province of Zambia. The aim was (1) to assess the capability of DSSAT in simulating crop responses to mulching and no-tillage, and (2) to understand the sensitivity of DSSAT model output to input parameters, with special attention to the determinants of the model response to the practice of CA. The model was first parameterized and calibrated for the tillage treatment (CP) of the experiment, and then run for the CA treatment by removing tillage and applying a mulch of crop residues in the model. In order to reproduce observed maize yields under the CP versus CA treatment, optimal root development in the model was restricted to the upper 22 cm soil layer in the CP treatment, while roots could optimally develop to 100 cm depth under CA. The normalized RMSE values between observed and simulated maize phenology and total above ground biomass and grain yield indicated that the CA treatment was equally well simulated as the CP treatment, for which the model was calibrated. A global sensitivity analysis using co-inertia analysis was performed to describe the DSSAT model response to 32 model input parameters and crop management factors. Phenological cultivar parameters were the most influential model parameters. This analysis also demonstrated that in DSSAT mulching primarily affects the surface soil organic carbon content and secondly the total soil moisture content, since it is negatively correlated with simulated soil water evaporation and run-off. The correlations between the input parameters or crop management factors and the output variables were stable over a wide range of seasonal rainfall conditions. A local sensitivity analysis of simulated maize yield to three key parameters for the simulation of the CA practice revealed that DSSAT responds to mulching particularly when rooting depth is restricted, i.e., when water is a critical limiting crop growth factor. The results of this study demonstrate that DSSAT can be used to simulate crop responses to CA, in particular through simulated mulching effects on the soil water balance, but other, often site-specific, factors that are not modeled by DSSAT, such as plough pan formation under CP or improved soil structure under CA, may need to be considered in the model parameterization to reproduce the observed crop yield effects of CA versus CP.     

小麦/玉米/大豆三熟套作体系中小麦根系分泌特性及氮素吸收研究

为探讨小麦/玉米/大豆多熟套作体系下小麦根系分泌物的分泌特性及其对根系生长环境和植株氮素吸收的影响,2006-2008年连续两个生长季采用田间定位试验,研究了小麦-大豆、小麦-甘薯、小麦/玉米/大豆和小麦/玉米/甘薯4种种植模式下小麦根系分泌物的数量与种类、小麦根系生长、土壤水分、土壤氮含量及植株吸氮量的变化特性。结果表明,与小麦-大豆和小麦-甘薯两种净作模式及小麦/玉米/甘薯套作模式相比,小麦/玉米/大豆套作降低了开花期和成熟期小麦生长区的土壤湿度、pH值及NO₃^--N和NH₄⁺-N的含量,提高了小麦植株地上部总吸氮量、根系活力、根干重及土壤总氮含量,并且,开花期小麦根系分泌有机酸总量和可溶性糖含量增加,表现为套作>净作,大豆茬口>甘薯茬口,边行>中行,其中以小麦边行处理的分泌量最高。拔节期根系分泌的有机酸,净作处理以乙酸含量较高,占总量的47.8%~51.6%,套作处理以柠檬酸含量较高,占总量的31.7%~55.1%;开花期根系分泌的有机酸,净作和套作处理均以乙酸含量较高,占总量的33.3%~78.3%。小麦/玉米/大豆套作对小麦根系分泌有机酸和可溶性糖有促进作用,从而改善了根系生长环境,提高了小麦对氮素的吸收。