陕西关中平原小麦/玉米轮作体系施肥现状调查与评价

【目的】调查和分析陕西关中平原农户施肥现状,为指导农民合理施肥提供参考。【方法】于2011-10-2012-03,在陕西省冬小麦/夏玉米轮作区,选择有代表性的10个县(区)(岐山、陈仓、扶风、泾阳、武功、兴平、杨凌、蒲城、富平、临渭),在每个县(区)选择代表性乡镇4~18个,每乡镇选择代表性村3~10个,每村选择4~5家农户,采用实地问卷调查形式,对冬小麦、夏玉米产量及田间管理和施肥情况进行调查,并对调查数据进行分析和评价。【结果】关中平原小麦纯N、P2O5和K2O平均用量分别为(210±106),(183±121)和(25±49)kg/hm2,小麦平均产量为(6.5±1.0)t/hm2;夏玉米纯N、P2O5和K2O平均用量分别为(288±113),(45±88)和(12±30)kg/hm2,玉米平均产量为(6.2±1.2)t/hm2。冬小麦施氮量适中的农户占33.6%,施氮量很低的农户占3.5%,偏低的占7.6%,偏高的占16.8%,很高的占38.5%。夏玉米施氮量适中的农户占11.2%,施氮量很低的占4.4%,偏低的占6.2%,偏高的占13.5%,很高的占64.7%。冬小麦N、P2O5和K2O主要以基肥方式施入,其中基施的N肥占总氮投入量的90%以上;夏玉米氮肥主要以拔节期追肥方式施入,基施氮肥约占总氮量的10%。冬小麦N、P2O5和K2O平均偏生产力分别为31.0,35.5,260.0kg/kg;夏玉米分别为21.5,137.8,516.7kg/kg。【结论】在关中平原小麦/玉米轮作体系中,氮肥施用过量严重,且前期投入偏多、后期投入偏少;磷肥偏高是目前该体系养分资源投入中的另一个问题,未来需要进一步加强对农民的宣传培训,使其科学合理施肥。     

AquaCrop模型在华北平原黑龙港流域典型区冬小麦-夏玉米种植模式上的适用性评价

为评估AquaCrop模型在黑龙港流域模拟冬小麦-夏玉米水分利用与作物产量的适用性,根据田间试验数据和FAO提供的参数值,对AquaCrop模型进行模型非保守性参数的本地化校准和验证。结果表明,AquaCrop模拟冬小麦冠层覆盖值和实测值的归一化均方根误差(NRMSE)为15.90%,模拟产量与实测产量之间的NRMSE为4.23%;模拟夏玉米冠层覆盖值和产量值与相应实测值之间的NRMSE分别为11.59%和11.69%。本研究校准所得参数对黑龙港流域典型站点有较好的适应性,校验后的AquaCrop可以用于黑龙港流域冬小麦-夏玉米水分管理、产量潜力等相关研究。     

气候变暖背景下黄淮海平原北部冬小麦生育期霜冻灾害发生规律

为探明气候变暖背景下黄淮海平原北部冬小麦生育期霜冻灾害发生规律,采用线性倾向估计、Mann-Kendall法和R/S分析法,分析1960-2017年的黄淮海平原北部12个气象站点0 cm地面最低温度数据.结果表明:1)年均气温表现出一致的上升趋势,北部升温速率高于南部.2)研究区初霜冻推迟,终霜冻提前,无霜期延长,初霜...     

冬小麦秸秆还田对夏玉米生长发育及产量的影响

【目的】探讨不同品种冬小麦秸秆、秸秆覆盖量和覆盖方式对夏玉米生长发育和产量的影响。【方法】于2012年在陕西关中一年两熟典型地区,采用随机区组设计,选用小偃22和小偃216 2个冬小麦品种秸秆,设秸秆混入耕层、秸秆带状覆盖、秸秆全面覆盖3种秸秆还田方式,以及4 500,7 500和10 500kg/hm2 3个秸秆还田量,以秸秆不还田为对照,于夏玉米幼苗期和发育中期测定株高、茎粗、次生根数、叶片颜色、单株干质量,并于成熟期测定株高、穗位高及产量构成因素,研究各处理对夏玉米生长发育及产量的影响。【结果】2012年夏玉米播种后由于较长时期干旱少雨,冬小麦秸秆覆盖的保墒作用大于其化感作用,各秸秆还田处理夏玉米生长发育及产量总体优于对照。在2个小麦品种秸秆中,以小偃216秸秆对夏玉米诸性状的表现较好;在3种秸秆还田量中,以7 500kg/hm2秸秆还田量较为适宜;3种秸秆还田方式中,则以秸秆带状覆盖方式对夏玉米生长发育影响较小;在此组合下,夏玉米幼苗和植株生长健壮,成熟期产量最高。【结论】对夏玉米进行秸秆覆盖时,以冬小麦秸秆覆盖量为7 500kg/hm2的带状覆盖方式最好。     

冬小麦、夏玉米品种搭配及氮磷钾统筹施肥技术研究

为提高冬小麦、夏玉米全年总产和肥效,试验在全年N、P、K肥施用总量分别为630、296、302 kg/hm2的情况下,探讨了上下茬配额及品种搭配对全年总产量的影响。4因子裂区设计,主处理为上下茬品种搭配,副处理、副副处理及次副副处理分别为N、K、P在上下茬的分配比例。品种搭配、K处理、N×P、N×P×K对年总产作用极显著,P处理、品种搭配×P×K作用显著。石新733与郑单958搭配,N平均分配,冬小麦施2/3的PK肥、夏玉米施1/3,是获取全年高产的最优方案,并突破了19 500 kg/hm2。N、P、K上下茬平均分配、或小麦均施2/3、或玉米均施2/3,都不利于全年高产。     

A simulation of winter wheat crop responses to irrigation management using CERES-Wheat model in the North China Plain

To improve efficiency in the use of water resources in water-limited environments such as the North China Plain(NCP), where winter wheat is a major and groundwater-consuming crop, the application of water-saving irrigation strategies must be considered as a method for the sustainable development of water resources. The initial objective of this study was to evaluate and validate the ability of the CERES-Wheat model simulation to predict the winter wheat grain yield, biomass yield and water use efficiency(WUE) responses to different irrigation management methods in the NCP. The results from evaluation and validation analyses were compared to observed data from 8 field experiments, and the results indicated that the model can accurately predict these parameters. The modified CERES-Wheat model was then used to simulate the development and growth of winter wheat under different irrigation treatments ranging from rainfed to four irrigation applications(full irrigation) using historical weather data from crop seasons over 33 years(1981–2014). The data were classified into three types according to seasonal precipitation: 100 mm, 100–140 mm, and 140 mm. Our results showed that the grain and biomass yield, harvest index(HI) and WUE responses to irrigation management were influenced by precipitation among years, whereby yield increased with higher precipitation. Scenario simulation analysis also showed that two irrigation applications of 75 mm each at the jointing stage and anthesis stage(T3) resulted in the highest grain yield and WUE among the irrigation treatments. Meanwhile, productivity in this treatment remained stable through different precipitation levels among years. One irrigation at the jointing stage(T1) improved grain yield compared to the rainfed treatment and resulted in yield values near those of T3, especially when precipitation was higher. These results indicate that T3 is the most suitable irrigation strategy under variable precipitation regimes for stable yield of winter wheat with maximum water savings in the NCP. The application of one irrigation at the jointing stage may also serve as an alternative irrigation strategy for further reducing irrigation for sustainable water resources management in this area.     

气候要素、品种及管理措施变化对河南省冬小麦和夏玉米生育期的影响

为揭示气候要素和品种及管理措施变化对冬小麦和夏玉米生育期的影响,利用1980—2014年河南省30个冬小麦站点和18个夏玉米站点的物候观测资料和逐日气象资料,通过一阶差分结合逐步回归的方法分析生长季温度、降水和辐射3个气候要素变化以及品种及管理措施变化对冬小麦、夏玉米全生育期和各生育阶段长度的影响。结果表明:1)河南省冬小麦返青期推迟,拔节、抽穗和成熟期提前;返青-拔节期、拔节-抽穗期分别缩短了4.8±1.9和3.3±0.9 d/10年,抽穗-成熟期延长了2.3±0.8 d/10年,全生育期长度无显著变化趋势。夏玉米大部分站点物候期变化趋势不显著;44%的站点全生育期延长,主要表现在抽雄-成熟期延长2.5±1.4 d/10年。2)冬小麦生长季温度升高,33%的站点降水减少,总辐射无显著变化趋势;气候要素变化主要发生在返青-拔节期。夏玉米生长季温度升高的站点占39%,降水量无显著变化趋势,39%的站点日均总辐射减少;温度升高主要发生在出苗-拔节期,日均总辐射减少主要发生在出苗-拔节期和抽雄-成熟期。3)冬小麦全生育期长度对温度、降水和辐射变化均较敏感,夏玉米全生育期长度对温度和辐射变化敏感。温度、降水和日均总辐射变化使河南省冬小麦全生育期平均缩短了6.3±4.2 d/10年,使夏玉米全生育期平均缩短了0.8±0.9 d/10年;而品种等其他因素使冬小麦和夏玉米全生育期分别延长了5.2±5.4和2.6±2.6 d/10年。气候要素变化缩短了河南省冬小麦和夏玉米的生育期,品种及管理措施等因素改变减缓了气候的负作用。但是各要素变化对河南省冬小麦、夏玉米全生育期、各生育阶段长度的影响仍存在较大的不确定性。     

The impacts of climate change on wheat yield in the Huang-Huai-Hai Plain of China using DSSAT-CERES-Wheat model under different climate scenarios

Climate change has been documented as a major threat to current agricultural strategies. Progress in understanding the impact of climate change on crop yield is essential for agricultural climate adaptation, especially for the Huang-Huai-Hai Plain(3 H Plain) of China which is an area known to be vulnerable to global warming. In this study, the impacts of climate change on winter wheat(Triticum aestivum L.) yield between the baseline period(1981–2010) and two Representative Concentration Pathways(RCP8.5 and RCP4.5) were simulated for the short-term(2010–2039), the medium-term(2040–2069) and the long-term(2070–2099) in the 3 H Plain, by considering the relative contributions of changes in temperature, solar radiation and precipitation using the DSSAT-CERES-Wheat model. Results indicated that the maximum and minimum temperatures(TMAX and TMIN), solar radiation(SRAD), and precipitation(PREP) during the winter wheat season increased under these two RCPs. Yield analysis found that wheat yield increased with the increase in SRAD, PREP and CO2 concentration, but decreased with an increase in temperature. Increasing precipitation contributes the most to the total impact, increasing wheat yield by 9.53, 6.62 and 23.73% for the three terms of future climate under RCP4.5 scenario, and 11.74, 16.38 and 27.78% for the three terms of future climate under RCP8.5 scenario. However, as increases in temperature bring higher evapotranspiration, which further aggravated water deficits, the supposed negative effect of increasing thermal resources decreased wheat yield by 1.92, 4.08 and 5.24% for the three terms of future climate under RCP4.5 scenario, and 3.64, 5.87 and 5.81% for the three terms of future climate under RCP8.5 scenario with clearly larger decreases in RCP8.5. Counterintuitively, the impacts in southern sub-regions were positive, but they were all negative in the remaining sub-regions. Our analysis demonstrated that in the 3 H Plain, which is a part of the mid-high latitude region, the effects of increasing thermal resources were counteracted by the aggravated water deficits caused by the increase in temperature.     

Effects of subsoiling depth,period interval and combined tillage practice on soil properties and yield in the Huang-Huai-Hai Plain,China

Compaction layers are widely distributed in the Huang-Huai-Hai Plain, China, which restrict root growth and reduce yields. The adoption of subsoiling has been recommended to disrupt compacted soil layers and create a reasonable soil structure for crop development. In this paper, the effects of subsoiling depth(30, 35 and 40 cm), period interval(2 or 3 years) and combined pre-sowing tillage practice(rotary cultivation or ploughing) on soil condition improvement was studied on a tidal soil in the Huang-Huai-Hai Plain. Seven tillage patterns were designed by combining different subsoiling depths, period intervals and pre-sowing. The evaluation indicators for soil condition improvement were as follows: thickness of the plough layer and hard pan, soil bulk density, cone index, soil three-phase R values, alkali nitrogen content, crop yield, and economic benefits. The results showed that subsoiling can significantly improve the soil structure and physical properties. In all subsoiling treatments, the depth of 35 or 40 cm at a 2-year interval was the most significant. The thickness of the plough layer increased from 13.67 cm before the test to 21.54–23.45 cm in 2018. The thickness of the hard pan decreased from 17.68 cm before the test to 12.09–12.76 cm in 2018, a decrease of about 40.07%. However, the subsoiling combined presowing tillage practice, that is, rotary cultivation or ploughing, was not significant for soil structure and physical properties. For all subsoiling treatments, the soil bulk density, cone index and soil three-phase R values of the 15–25 cm soil layer were significantly lower compared to single rotary cultivation. Subsoiling was observed to increase the soil alkaline nitrogen and water contents. The tillage patterns that had subsoiling at the depth of 35–40 cm at a 2-year interval combined with rotary cultivation had the highest alkali nitrogen and water contents, which increased by 31.08–34.23% compared with that of the single rotary cultivation. Subsoiling can significantly increase the yield both of wheat and corn, as well as the economic benefits. The treatment of subsoiling at the depth of 35 cm at an interval of 2 years combined with rotary cultivation had the highest annual yield and economic benefits. For this treatment, the annual yield and economic benefits increased by 14.55 and 62.87% in 2018, respectively. In conclusion, the tillage patterns that involved subsoiling at a depth of 35 cm at a 2-year interval along with rotary cultivation are suitable for the Huang-Huai-Hai Plain.     

基于CiteSpace的华北冬小麦-夏玉米周年优化灌溉制度的节水潜力分析

为探究华北地区冬小麦-夏玉米一年两熟制周年优化灌溉制度的节水潜力,基于文献计量学方法,系统梳理了1995—2020年有关华北地区冬小麦-夏玉米一年两熟制周年优化灌溉制度的文献发文量、被引量、高影响力期刊、作者、研究单位、高频词、试验站点,以分析其研究态势,并利用CiteSpace进行了可视化与关联分析。在此基础上,进一步整理了该模式中高灌溉需水量作物冬小麦的关键节水技术,包括了工程节水技术(喷灌、滴灌、微喷灌)、生物节水技术(品种选育)与典型农艺节水技术(优化灌溉制度)等,系统分析了各节水技术对冬小麦产量、耗水量、水分利用效率的影响。结果表明:1)华北地区冬小麦-夏玉米一年两熟制周年优化灌溉制度研究的相关发文量在近年来呈明显增加趋势,发展态势良好,但同时缺乏高被引论文。中国农业大学、中国科学院遗传与发育生物学研究所农业资源研究中心、河南农业大学发文数量排在前三位,分别占总发文数的27%、10%和10%,在该领域具有较高的活跃度;2)从高频词来看,该领域主要聚焦于水分利用效率、产量、光合特性、生长特性、模型模拟等。但相关领域也存在问题,如主要作者、一些研究机构间合作不够密切,田间实验站点分布不均匀且缺少长期稳定的定位观测试验等;3)对于高灌溉需水量作物冬小麦的文献计量研究表明,喷灌、滴灌、微喷灌、选用抗旱节水品种等技术,可降低田间耗水量7%~13%、产量不同程度增加2%~10%,水分利用效率提高约5%~28%。优化灌溉制度,减少灌溉次数,且根据不同降水年型保证冬小麦关键生育期的需水,可降低田间耗水9%~25%,产量降低2%~18%,水分利用效率提高约6%~9%。综上,为进一步保证粮食生产与水资源安全,应将冬小麦-夏玉米一年两茬作为一个整体来充分考虑周年的水分利用,合理优化周年的灌溉制度,构建整合配套的农艺节水技术体系和灌溉设备与技术。     

黄淮海平原地区深松和灌水次数对冬小麦- 夏玉米节水增产的影响

目的 研究黄淮海平原地区冬小麦-夏玉米不同深松时机交互不同灌水次数对作物产量及水分生产效率的影响,为优化黄淮海地区土壤耕作方式提供理论依据。方法 采用土壤耕作方式与灌水次数相结合的方法,设置秋深松+冬小麦2水（QS-2）、秋深松+冬小麦3水（QS-3）、夏深松+冬小麦2水（XS-2）、夏深松+冬小麦3水（XS-3）、对照（CK）共5个处理,研究深松与灌水次数对冬小麦-夏玉米一年两熟农田土壤物理性质、植株生长发育、产量、总产出值及水分生产效率等的影响。结果 深松和灌水次数对土壤容重、土壤紧实度、土壤储水量、总产出值、水分生产效率均有不同程度显著影响。与对照相比,QS-2、XS-2、XS-3处理均显著降低深松后第1年土壤耕层（0—40 cm）及深松后第2年0—20 cm土层的土壤容重;深松各处理均显著降低第1年土壤紧实度,对第2年土壤紧实度影响效果不明显;秋深松后第2年QS-2处理的冬小麦整个生育期平均土壤储水量较CK显著增加18.14%,QS-3处理次之,夏深松后第2年XS-2、XS-3处理分别较CK显著提高24.7%、25.6%;秋深松能显著提高当季冬小麦生长发育,QS-2、QS-3处理地上生物量分别较CK增加了19.29%、27.06%,第2年QS-2和QS-3处理地上生物量较CK均有所提高,差异不显著,秋深松对第2年冬小麦生长发育影响效果减弱,夏深松第2年XS-2和XS-3处理的叶面积和地上生物量均较对照显著提高,夏深松能显著促进后茬冬小麦生长发育;QS-2处理对2年冬小麦-夏玉米总产出值和水分生产效率均显著提高,第1年总产出值和水分生产效率分别较CK提高27.21%、23.51%,第2年分别提高19.54%、18.84%,夏深松显著提高第2年冬小麦-夏玉米总产出值及水分生产效率,XS-2处理分别提高18.50%、17.65%,XS-3处理分别提高19.57%、15.35%。结论 黄淮海平原冬小麦-夏玉米连作采用冬小麦播前秋深松耕作方式,冬小麦全生育期灌水2次,有利于降低农田土壤容重、降低土壤紧实度、提高土壤储水效果、显著提高深松周期内冬小麦-夏玉米总产出值及水分生产效率。建议在黄淮海平原地区平水年和丰水年（夏玉米季降雨充沛）,冬小麦-夏玉米种植区采用秋深松+冬小麦灌2水耕作模式,实现高产与高效。     

华北冬小麦开花及成熟期变化特征分析

利用华北平原59个农业气象观测站1981—2010年冬小麦生育期资料,分析了该区域冬小麦在气候变暖背景下开花期和成熟期的变化趋势特征。研究结果表明：近30年来,华北平原冬小麦开花期和成熟期均发生了明显变化。相对1980s而言,1990s开花期普遍提前2～5 d,成熟期提前1～6 d左右,2000s开花期则一般提前3～9 d,成熟期提前1～7 d左右。因此,随着年代推进,华北平原冬小麦开花期和成熟期提前趋势在进一步加剧。相对1980s而言,1990s生育期等值线普遍北移,而2000s等值线进一步北移的趋势更加明显。研究发现,3—5月月平均气温升高是开花期和成熟期提前的一个重要影响因素。     

近20年黄淮海地区气候变暖对夏玉米生育进程及产量的影响

【目的】探求黄淮海地区近20年气候变暖对夏玉米生长发育进程及产量的影响,为气候变暖背景下夏玉米的高产稳产制定合理的应对措施提供理论依据。【方法】选取黄淮海地区,包括河北、京津地区、河南、山东、安徽和江苏等地区进行区域研究,利用该地区近20年长期观察的气候数据和夏玉米生产数据以及历史产量数据,采用相关分析和非线性多元回归等分析方法,明确气候因子（温度和降水）与夏玉米生育期和产量的关系。【结果】近20年间黄淮海大部分地区夏玉米生长季内区域平均温度呈上升趋势,但存在地区间差异。降水方面,该区东北部的京津-河北地区与山东降水量呈下降的趋势。与1990s相比,2000s河北和山东夏玉米营养生长期天数呈下降趋势,分别下降2 d和1 d,河南呈上升趋势,增加1 d;而生殖生长期呈上升趋势,分别上升4 d和2 d,河南下降1 d。全生育期天数有所增加,平均增加2 d和1 d。河南保持不变。利用F检验法分析审定品种和试验地玉米全生育期线性趋势一致性。结果表明,审定品种生育期和试验地玉米生育期变化呈现一致的趋势,说明品种的变化是影响夏玉米生育期的因子。采用线性偏回归测验法分析品种和气候因子对夏玉米生育期影响重要性。结果表明,气候因子是夏玉米生育期变化的主要因子,影响率占75.3%。黄淮海地区（除江苏外）夏玉米产量以增产为主。非线性分析表明,气温升高会导致黄淮海地区北部的河北与西部的河南夏玉米产量上升,东南部地区各省份夏玉米的减产。降水对该地区干旱少雨的北部地区夏玉米产量有正效应,对湿润多雨的南部地区有负效应。此外,当GDD10上升时,黄淮海地区北部的河北与西部的河南的夏玉米产量会随着上升,而东部和南部的山东、安徽与江苏夏玉米产量将会下降;整个黄淮海地区,当GDD30上升时,会造成全地区夏玉米产量下降,且山东下降最为明显。【结论】黄淮海地区夏玉米的实际生产受气候变暖的影响,夏玉米对气候变暖是逐步适应,可以利用其适应潜力,通过选育生育期长和耐热的夏玉米品种和改进栽培措施来适应气候变暖,从而提高夏玉米产量。     

黄淮海地区冬小麦-夏玉米生育期内水分供需时空变化特征

为明确影响黄淮海地区作物需水的关键气象因子及其变化特征,基于该地区的66个国家标准气象站点1987—2016年长时间序列的逐日观测资料,采用敏感性分析、因子趋势检测和GIS空间分析等方法,定量计算冬小麦-夏玉米生育期内的有效降水量(Pe)、作物需水量(ETc)及灌溉需水量(ETaw),分析1987—2016年黄淮海区冬小麦-夏玉米水分供需的时空变化特征以及ETc对不同气象因子的敏感性差异。研究表明,1987—2016年冬小麦生育期内Pe远不能满足其生长需求,年均ETaw达264mm,特别冬小麦生育期内Pe呈较明显的下降趋势,伴随气温不断升高,使其面临较严重的水分亏缺;而夏玉米生育期与Pe耦合度高,年均ETaw仅为79mm。黄淮海地区北部为冬小麦ETc和ETaw的高值区,南部ETaw相对较低,但1987—2016年增加趋势明显。相对湿度和气温对ETc的影响最大,其次是平均风速和日照时数,相对湿度的减少和气温的显著升高都将导致ETc的增加。     

华北平原夏玉米不同施氮措施的综合增温潜势研究

为探究和利用高固碳、低排放的农业管理措施,以华北平原夏玉米生产为研究对象,采用大田试验和生命周期评价方法,设置对照(CK)、低氮肥(LF)、适宜氮肥(SU)、减排(适宜氮肥+抑制剂,ER)以及高氮肥(HF)5种施氮处理,定量评估夏玉米生产全过程中的土壤排放温室气体增温潜势(GWP_Soil)、农业投入增温潜势(GWP_Indirect)、净初级生产力增温潜势(GWP_NPP)、净综合增温潜势(Net GWP)和农田经济效益。结果表明:不同处理总排放增温潜势(GWP_Soil+GWP_Indirect)为10 831.3~14 301.9 kg/hm²(以CO₂当量计),由高到低依次为HF>SU>LF>ER>CK;HF的GWP_Soil及GWP_Indirect均为最高,较CK处理分别高10.9%和153.3%;GWP_Soil对总排放量的贡献较大(>70%),农业投入中肥料对GWP_Indirect的贡献最大,为54.1%~69.7%(CK除外),灌溉次之;华北平原夏玉米农田Net GWP为负值,是大气的碳汇,SU和ER处理Net GWP最大,绝对值分别较CK处理高 18.1% 和17.9%。综上,ER和SU处理净利润最高,属于高收益-高固碳种植管理模式,但ER与SU处理相比,ER的GWP_Soil降低了8.7%,更有利于温室气体减排,适合作为绿色农业发展模式在华北平原推广。     

Influence of maize straw amendment on soil-borne diseases of winter wheat

A field experiment was conducted during the 2006–2007 wheat growing season at Baoding, Hebei Province, China, aiming at exploring the influence of different amendment rates of maize straw on winter wheat soil-borne diseases induced by Rhizoctonia cereali, Gaeumannomyces graminis and Bipolaris sorokiniana in field conditions. Wheat root vitality, ion infiltration, SOD activity, MDA content and microbial population of the tillage layer were measured. The results showed that the occurrence of three soil-borne diseases tested was significantly different under different amendment rates. During the greening stage and jointing stage, the disease indexes of three soil-borne diseases were reduced significantly by treatments at the maize straw amendment rates of 7500 kg · hm⁻² and 3750 kg · hm⁻². However, disease indexes of wheat common rot and sharp eyespot increased dramatically when the amendment rate increased to 15000 kg · hm⁻². At the amendment rate of 15000 kg · hm⁻², wheat root vigor and SOD activity decreased, and ion infiltration and cell membrane-lipid peroxidation level increased, respectively. In the meantime, higher amounts of bacteria and actinomycetes were recorded in the 7500 kg · hm⁻² amendment rate treatment, while a higher amount of fungi was recorded in the 15000 kg · hm⁻² amendment rate treatment.     

CO2倍增时气候及其变率变化对黄淮海平原冬小麦生产的影响

对CO2有效倍增条件下黄淮海平原气候变率的可能变化提出了3种假设,然后利用哥达德空间研究所研制的大气环流模型(GISSGCM)的有关网格点值,结合研究区域6个样点近40年(1961～2000)的逐日气候资料以及DSSAT(农业技术转化决策支持系统)中的WGEN(天气发生器),生成了黄淮海平原(2×CO2)条件下兼顾气候及其变率变化的3种情景。在上述3种情景下分别运行CERES Wheat(作物 环境资源综合系统 小麦模型),并与当前气候(BASELINE)条件下的模拟值进行比较,评价了(2×CO2)条件下气候及其变率变化对冬小麦生产的影响,同时考虑了大气CO2浓度的直接影响。结果表明,在(2×CO2)条件下,灌溉小麦的模拟产量在所有样点都增加了,但随着气候变率的增大,增产幅度减小,产量变异系数增大,稳产性变差;雨育小麦的模拟结果与灌溉小麦相似,但稳产性明显低于灌溉小麦。     

Calibration and validation of SiBcrop Model for simulating LAI and surface heat fluxes of winter wheat in the North China Plain

The accurate representation of surface characteristic is an important process to simulate surface energy and water flux in land-atmosphere boundary layer. Coupling crop growth model in land surface model is an important method to accurately express the surface characteristics and biophysical processes in farmland. However, the previous work mainly focused on crops in single cropping system, less work was done in multiple cropping systems. This article described how to modify the sub-model in the SiBcrop to realize the accuracy simulation of leaf area index(LAI), latent heat flux(LHF) and sensible heat flux(SHF) of winter wheat growing in double cropping system in the North China Plain(NCP). The seeding date of winter wheat was firstly reset according to the actual growing environment in the NCP. The phenophases, LAI and heat fluxes in 2004–2006 at Yucheng Station, Shandong Province, China were used to calibrate the model. The validations of LHF and SHF were based on the measurements at Yucheng Station in 2007–2010 and at Guantao Station, Hebei Province, China in 2009–2010. The results showed the significant accuracy of the calibrated model in simulating these variables, with which the R~2, root mean square error(RMSE) and index of agreement(IOA) between simulated and observed variables were obviously improved than the original code. The sensitivities of the above variables to seeding date were also displayed to further explain the simulation error of the SiBcrop Model. Overall, the research results indicated the modified SiBcrop Model can be applied to simulate the growth and flux process of winter wheat growing in double cropping system in the NCP.     

黄淮海平原微喷灌下冬小麦农田水分渗漏及氮素淋失模拟分析

为了解黄淮海平原冬小麦水分渗漏和氮淋失特征,以优化小麦生产灌溉制度,降低农田水肥施用后土壤氮淋失对环境的影响,本试验于2020—2022年在设置不同灌水处理(充分灌溉、亏缺灌溉)和雨养处理的大田试验基础上,利用土壤-作物系统水热碳氮耦合(WHCNS)模型,通过优化土壤水力学和作物参数,评价模型适用性,并使用校验后的模型定量化分析不同水分管理条件下的农田氮淋失、水分渗漏及特征。结果表明：土壤含水率和硝态氮(以N计)的均方根误差范围分别为0.01～0.07 cm³·cm^-3和3.37～6.39 mg·kg^-1;叶面积指数和干物质量模拟R²≥0.9,一致性指数均≥0.7,模型模拟达到预期效果。使用校验后的模型对0～100cm土层水分渗漏和氮淋失进行动态模拟的结果显示,硝态氮淋失与水分渗漏动态一致,二者均表现为单日量小且持续时间较长,产生渗漏的累计天数占全生育期天数的59.2%～69.4%。与充分灌溉相比,亏缺灌溉在两季冬小麦产量无显著差异的情况下,日氮淋失和水分渗漏量分别减少3.88%～66.94%和37...