Long-Term Effects of Nitrogen Management Practices on Grain Yield,Nitrogen Uptake,and Efficiency in Irrigated Corn

ABSTRACT

Crop management strategies that improve Nitrogen Use Efficiency (NUE) increase profits while reducing the detrimental effects on the environment associated with fertilizer nitrogen (N) loss. Effective N management should include several critical factors that are very interrelated. A study was conducted at the Panhandle Research and Extension Center, Goodwell, OK to evaluate the effects of multiple nitrogen management practices including N rate, source, time of application, methods of fertilizer and residue incorporation over a long period of time on grain yield, N uptake and NUE in irrigated corn. Fourteen treatments were evaluated in a randomized complete block design with three replicates. Results of data analyzed on the individual year and averages of all years showed that grain yield and N uptake were improved with N rates and N management practices compared to checks. Both N recovery and efficiency of use were high for the 118 kg N ha^{? 1} rate.     

黑龙江风沙土区不同耕作措施对玉米地土壤水分及产量的影响

针对黑龙江省西部风沙土区干旱频繁发生、土壤风蚀严重的特点,采取打茬播种、旋耕播种、免耕等不同保护性耕作措施,与当地传统耕作的玉米进行对比试验。结果表明:旋耕措施对土壤含水量具有显著改善作用。旋耕处理土壤结构较好,能够有效接纳降水,增大储水库容;免耕条件下对土壤水分的影响主要表现在玉米生长前期及中期,免耕处理耕作次数较其它处理少,在春季保持了底层土壤水分。旋耕处理的玉米产量最高,与对照相比增加了31.2%;其次为打茬播种处理,产量比对照增加了13%;免耕处理的玉米产量最低,与对照相比产量降低了20.4%。     

耕作方式和氮肥水平对旱地冬小麦籽粒品质的影响

为研究不同耕作方式和氮肥水平对旱地冬小麦籽粒品质的影响,选择常规耕作(CT)、秸秆还田(CTI)、全膜覆土穴播(PM)、免耕秸秆覆盖(NTS)4种耕作方式和75(N1)、150(N2)、225(N3)、300 kg·hm~(-2)(N4)4个氮肥水平,在典型的西北旱作雨养农业区甘肃省农业科学院小麦研究所清水试验站设计大田试验。结果表明,耕作方式和氮肥水平对小麦蛋白质及其组分含量、湿面筋、面团稳定时间、籽粒产量均有显著或极显著影响。与CT相比,PM显著提高了谷蛋白含量和谷醇比,延长了面团稳定时间,有利于加工品质的改善;而NTS的蛋白质总量、湿面筋、球蛋白、麦谷蛋白、谷醇比均显著低于CT。施氮显著提高了籽粒蛋白质、湿面筋、蛋白质各组分含量,增加了面团延伸性和吸水率。与N1相比,N4冬小麦的醇溶蛋白、麦谷蛋白、球蛋白、清蛋白分别增加了56.38%、27.60%、20.87%、17.03%;在4种蛋白组分中,施氮更有利于醇溶蛋白的累积,因此过量的氮肥应用显著降低了谷醇比、缩短了面团稳定时间和最大拉伸比值。同一氮肥水平下,不同耕作方式处理的小麦籽粒平均产量依次为PMCTICTNTS,PM下的平均产量为6 259.63 kg·hm~(-2),比CTI、CT、NTS分别高6.24%、10.54%和20.95%。同一耕作方式下,不同氮肥水平处理的小麦籽粒平均产量依次为N2N3N4N1,其中N2下小麦籽粒平均产量达到6 184.64 kg·hm~(-2),比N3、N4、N1分别高5.78%、7.31%、19.06%。综上可知,在甘肃半干旱雨养农业区实施全膜覆土穴播栽培模式,并增施150 kg·hm~(-2)氮肥,既能大幅度增加小麦籽粒产量,也有利于加工品质的改善,是该地区小麦生产实现高产和优产的最佳耕作和供氮模式。本研究结果为甘肃旱作雨养农业区冬小麦的高产、优质栽培提供了理论参考。     

新型玉米免耕播种机的试验研究

研制了一种小型适用于小麦玉米两茬平作区的具有深松、播种、施肥功能的玉米免耕播种机,获国家实用新型专利。该机施肥播种共用一个窄幅开沟器,化肥点施于两穴种子之间,可一次完成深松、开沟、施肥、播种、覆土、镇压工序。生产试验表明,各项技术性能满足农业种植要求。本机被农业部选为全国首批推荐精少量播种机具。     

Plant Density and Hybrid Impacts on Corn Grain and Forage Yield and Nutrient Uptake

ABSTRACT

Corn (Zea mays L.) production recommendations should be periodically evaluated to ensure that production practices remain in step with genetic improvements. Since most of the recent increases in corn grain yield are due to planting at higher densities and not to increased per-plant yield, this study was undertaken to measure the effects of plant density and hybrid on corn forage and grain yield and on nutrient uptake. Plant density (4.9, 6.2, 7.4, and 8.6 seeds m^?2) and hybrid relative maturity (RM) [early (108 day RM); medium (114 day RM); and late (118 day RM)] combinations were evaluated over five site-years under irrigated and non-irrigated conditions. The interaction of hybrid with plant density was never significant for grain, stem, or leaf biomass. The latest RM hybrid out-yielded the medium and early hybrids by 550 and 1864 kg ha^?1, respectively. Grain yield was highest at 8.6 plants m^?2. Total stem yield was also greatest at the highest plant density but by only 340 kg ha^?1 more than at 7.4 seeds m^?2. Based on grain yield response over sites, the estimated optimum density was 7.6 seeds m^?2, which is 0.7 seeds m^?2 higher than the current recommendation at this average yield level (11.5 Mg ha^?1). Grain nitrogen (N), phosphorus (P), and potassium (K) uptakes were highest for the medium RM hybrid. Nutrient uptake levels varied by planting density, with the lowest levels observed at the lowest and highest plant densities. At 4.9 seeds m^?2, the reduced uptake is explained by lower biomass yields. At the 8.6 seeds m^?2 rate, N and K levels may have been lower due to dilution.     

Nitrogen Status of Pollen Donor Affects Kernel Set and Yield Components in Corn

ABSTRACT

Nitrogen (N) status of corn plants influences yield performance through adjustment of yield components. Physiological function of corn pollen produced under N-stressed conditions has not drawn enough attention in genotype selection and breeding programs. The object of this study was to assess effects of N nutrition of the pollen donor on kernel set and yield components of the pollen recipient in a field trial by using a restricted pollination procedure. Pollen from plants receiving 0 and 240 kg N ha^?1 was manually applied to plants receiving 0, 80, 160, and 240 kg N ha^{? 1} during silk emergence. The high rate of N fertilizer applied to the pollen donor significantly increased kernel number, kernel weight, harvest index, and aboveground biomass in the pollen recipient. The effect of N nutrition of the pollen donor was similar at all N levels that were applied to the pollen recipient so the interaction was not significant for any of the variables.     

春玉米产量、氮肥效率及土壤矿质氮对施氮的响应

为了提高氮肥增产效益,减少对环境的污染,通过田间试验研究了施氮量对春玉米产量、氮肥效率及土壤矿质氮的影响。结果表明,施氮量较低时,春玉米籽粒产量随施氮量增加显著增加,当施氮量高于180 kg·hm-2时,产量保持不变或有减少趋势。氮肥农学利用率、氮素吸收效率、氮素偏生产力和氮收获指数均随着施氮量增加显著降低,氮肥表观利用率和氮肥生理利用率均先增加后降低。从苗期到收获期,施氮处理0~60 cm土层硝态氮含量呈现"上升—下降—上升—下降—稳定"的变化趋势,而60~120 cm土层硝态氮在春玉米生长后期有增加的趋势。随着土层加深,土壤硝态氮含量呈波浪式下降,施氮量240 kg·hm-2和300 kg·hm-2处理在60~100 cm土层硝态氮含量均显著高于其他处理。随着施氮量增加,0~120 cm土层硝态氮累积量显著增加,当施氮量超过240kg·hm-2时,土层中累积的硝态氮存在着较大的淋溶风险。综合考虑产量、氮肥效率和环境效应,179~209 kg N·hm-2是本试验条件下春玉米的合理施氮量。     

Effect of Nitrogen on Yield and Some Quality Parameters of Sweet Corn

Sweet corn consumption has increased considerably worldwide. Sweet corn is produced for human consumption as either a fresh or a processed product. The nutrient composition of sweet corn is very important for human health and diet. This study aimed to determine the best nitrogen (N) dosage for sweet corn. Kernel mineral composition and protein content were determined for different N rates. The research was carried out during 2003 and 2004 in Sanliurfa, Turkey. Nitrogen application rates were 120, 160, 200, 240, 280, 320, and 360 kg N ha^?1 with control. The fresh ear yield per hectare and the protein and mineral contents of kernel were significant (P < 0.01). The lowest yield was obtained at low N applications, whereas increasing N applications increased the fresh ear yield and protein content of kernel. Nitrogen-use efficiency increased up to 320 kg ha^?1 N dosage (60.2% and 58.6% for 2003 and 2004, respectively), and a decrease was seen at 360 kg ha^?1 N dosage. Leaf area index and root dry matter increased with increasing N supply. The copper concentration of the kernel was generally positively affected by increasing N application. Iron and zinc contents of kernels increased, whereas manganese content decreased, with increasing N doses. At the focus of regression analysis, the best N dosage was 320 kg ha^?1 along with the soil N content for Vega sweet corn variety grown in the southeastern Anatolia region of Turkey.     

施氮与灌水对河西制种玉米产量及水氮利用效率的影响

为探究施氮和灌水对河西灌区制种玉米种子产量以及生产过程中水氮利用的影响,以郑单958(ZD958),先玉335(XY335)为研究对象,设置充分灌水(6 000 m~3·hm~(-2),W_(6000))、中度胁迫(4 500m~3·hm~(-2),W_(4500))、重度胁迫(3 000 m~3·hm~(-2),W_(3000))3个灌水梯度,不施氮(0 kg·hm~(-2),N_0)、中量施氮(225 kg·hm~(-2),N_(225))、过量施氮(450 kg·hm~(-2),N_(450))3个施氮水平,测定收获期种子产量及产量构成,以及播前收后1m深土壤含水量及土壤硝态氮含量。结果表明,灌溉量对种子产量无显著影响,同一灌水条件下施氮处理产量显著高于不施氮,先玉335组合产量较郑单958组合高,最高产量出现在中度胁迫灌水条件下的过量施氮处理(W_(4500)N_(450)),达11 147 kg·hm~(-2);先玉335组合的种子百粒重显著高于郑单958组合,郑单958组合种子各产量构成均表现为施氮处理高于不施氮。在中度胁迫灌水条件下,0~100cm土壤硝态氮的累积量显著高于重度胁迫和充分灌水;水分利用效率、氮肥偏生产力、氮肥农学效率均以中度胁迫灌水条件下中量施氮处理占优。综合考虑产量及水氮利用效率,在本试验条件下,适合河西灌区郑单958制种组合和先玉335制种组合的水氮最佳组合为灌水量4 500 m~3·hm~(-2),施氮量225 kg·hm~(-2)。本研究为河西制种玉米种植中水氮合理利用提供了理论借鉴。     

连续施氮对玉米产量稳定性及其增产潜力的调控

通过7年的定位试验(2007~2013年),研究不同施氮水平对辽北地区玉米产量稳定性、可持续性及其增产潜力的影响。试验氮肥用量从低到高共设N0(不施氮)、N_1(138 kg hm~(-2))、N_2(241.5 kg hm~(-2))、N_3(345 kg hm~(-2))4个水平。结果表明,施氮可以显著增加玉米产量,在一定范围内产量和产量稳定性随施氮量的增加而增加,其中N2处理的产量(平均产量9598.1kg hm~(-2))和增产率(70.7%)最高,年际间变异系数最小,相应的稳定性最高;N_3处理虽然施氮量比N_2处理增加43%,然而产量和产量的稳定性并没有显著提高。根据7年的平均产量研究结果得出肥料-产量效应函数,曲线符合报酬递减率,可知玉米增产潜力为1279.3 kg hm~(-2),由此说明辽北地区的玉米单产还有很大的增产空间。     

Tillage and Lime Rate Effects on Soil Acidity and Grain Yields of a Ten-Year Corn–Soybean Rotation

Reduced tillage and no-tillage systems provide shallow incorporation of surface applied materials at best. Due to concern of over-liming the surface of agricultural soils, producers either reduce lime rates (and apply more often) or perform some sort of soil inversion to mix the lime deeper into the soil profile. The objective of the authors in this field study was to evaluate the effects of tillage, lime rate, and time of limestone application on corn and soybean growth, and assess the changes in soil acidity to an already acidic soil. Treatments consisted of a no lime check, two no-tillage systems with either a 4.5 ton ha^?1 lime application every two years or an annual application of 450 kg pelleted lime ha^?1, a continuous annual chisel tillage system with a 9.0 ton ha^?1 lime application every four years, and two inversion systems utilizing a rotary tiller (Howard Rotovator) where 9.0 ton lime ha^?1 was mixed into the soil followed by either continuous chisel tillage or continuous no-tillage. Inversions occurred in 1999, 2003, and 2007. Soil samples were collected annually in increments of 5 cm to a 30 cm depth for pH determinations. After 10 years, the continuous chisel system increased soil pH in the top 20 cm and had grain yields comparable to the no-tillage system, but not different than the no lime treatment. The no-tillage system increased the pH in the surface 15 cm of soil. The inversion treatments after soybean mixed the lime more thoroughly in the top 15 cm than inversion after corn and also increased the pH to a deeper depth. The pelleted lime had no effect on soil acidity. Soybean yields were affected by lime treatment with the no lime and pelleted lime having the lowest yields. This is most likely due to manganese (Mn) toxicity with these treatments. There was no perceived benefit of inversion of the soil with no-till or chisel systems.     

减氮配施氮肥增效剂对土壤速效氮和玉米产量的影响

过量施氮一直是玉米生产中存在的主要问题,而配施氮肥增效剂可作为减氮条件下玉米实现高产和稳产的一种重要技术措施。2016—2017年在四川省德阳市中江县合兴乡新建村设置田间试验,研究不同施氮量与氮肥增效剂配施对土壤速效氮含量和玉米干物质积累及产量的影响,为玉米减氮增产栽培技术提供科学依据。结果表明:减氮配施增效剂能够增强土壤速效氮供应能力,促进玉米干物质积累,改善产量构成,提高玉米产量,实现玉米减氮不减产。常规氮和减氮20%配施增效剂增产幅度分别为5.53%～13.97%和10.24%～17.05%,减氮配施增效剂的增产效果更好。减氮20%条件下A_2B_4脲酶活性和土壤硝态氮含量较A_2B_2、A_2B_32年平均分别降低了19.00%,15.65%和-2.97%,57.24%,土壤铵态氮含量和产量2年平均提高11.48%,248.50%和3.71%,6.18%。综上,减氮20%条件下硝化抑制剂(DCD)和脲酶抑制剂(HQ)复配土壤速效氮的供应能力最强,可实现玉米减氮不减产。     

旱地玉米保护性耕作机具与作业工艺的组合研究

多年保护性耕作试验取得了保墒增产的明显效果,但也暴露出播种质量不高等问题,仅靠改进机具已难以解决。１９９６年开始增加表土耕作进行配套试验。通过对不同试验处理的秸秆覆盖率、地温、土壤含水量、出苗率和作物产量对比,初步得出增加表土耕作组合方案可以调控地表秸秆覆盖量、改善地面状况、提高地温、保苗增产。在我国北方,干旱低温,秸秆不易腐烂,逐年积累,故应该把表土耕作列为保护性耕作体系的重要内容,只有把作业工艺选择与播种机性能改进结合,才能更有效地解决免耕播种质量不高的问题。     

耕作方式对紫色水稻土颗粒态氮的影响

土壤颗粒态氮作为土壤有机氮中的非稳定性部分,对土壤中氮的平衡有着重要的影响,对作物的生长及增产增收也有着重要意义.试验以西南大学农业部重庆紫色土生态环境重点野外科学观测试验站内于1989年设立的长期免耕试验田为研究对象,研究冬水田平作、水旱轮作、垄作免耕和垄作翻耕等耕作方式对土壤颗粒态氮的影响.结果表明,不同耕作方式下土壤全氮及颗粒态氮含量均具有明显的垂直分布特征,由上到下含量逐渐降低.在0-60 cm的土壤深度内,土壤全氮平均含量依次为垄作免耕(1.53g/kg)>冬水田平作(1.50 g/kg)>垄作翻耕(1.31 g/kg)>水旱轮作(1.16 g/kg);颗粒态氮平均含量依次为冬水田平作(0.55 g/kg)>垄作免耕(0.46 g/kg)>垄作翻耕(0.40 g/kg)>水旱轮作(0.35 g/kg).免耕能够增加土壤全氮含量,但无助于颗粒态氮含量的增加.不同耕作方式下的颗粒态土碳氮比大于全土碳氮比,表明颗粒态土壤有机质易被微生物分解,是土壤营养物质的重要来源.     

氮肥后移对强筋小麦氮素积累转运及籽粒产量与品质的影响

为探索强筋小麦施用氮肥的合理基追比模式,在山西中部麦区水地小麦田,研究了氮肥基施、拔节期追施和孕穗期追施的不同比例(10∶0∶0,7∶3∶0,7∶2∶1,6∶4∶0,6∶2∶2,5∶5∶0,5∶3∶2)对强筋小麦CA0547氮素积累转运及籽粒产量与品质的影响。结果表明:(1)适当追氮对强筋小麦CA0547氮素与干物质积累转运及产量品质有显著的调节效应。(2)追氮能显著提高小麦拔节期后的含氮量,提高花前氮素转运量和花后氮素积累量,促进氮素向籽粒中的累积,同时增加花前干物质转运量和花后干物质积累量,为产量提高提供了物质基础。(3)籽粒氮素中约有68.38%~75.18%是来自花前氮素转运,籽粒产量中约有55.12%~70.04%是来自花后干物质积累。追氮通过显著增加穗数和穗粒数来提高产量,并提高氮素吸收效率和氮素生产效率。(4)追氮可提高籽粒醇溶蛋白、谷蛋白、总蛋白质和湿面筋含量,提高面筋指数和淀粉含量,改善谷醇比和直/支比,进而改善籽粒品质。相关分析亦表明,提高干物质花后积累量与花前氮素转运量可以改善小麦品质。(5)拔节期和孕穗期2次施氮效果不如拔节期1次追施。综合分析得出,在本试验条件下,施氮量150kg/hm~2时,基肥、拔节肥、孕穗肥比例为6∶4∶0能较好的协调产量品质之间的关系。     

稳定氮肥用量对夏玉米产量和氮肥利用率的影响

通过大田小区试验,研究了稳定氮肥不同用量对夏玉米产量、养分累积量、氮肥利用效率及经济效益的影响。结果表明,与不施稳定氮肥相比,稳定氮肥施氮量90、150、210 kg·hm-2和270 kg·hm-2分别增产36.7%、62.1%、76.6%和81.9%,地上部氮素总累积量分别增加39.0%、60.3%、79.0%和113.4%,经济效益分别增加36.1%、61.2%、72.7%和77.1%;与农民习惯施用氮肥相比,高量稳定氮肥用量210 kg·hm-2和270 kg·hm-2分别增产7.3%和10.5%,地上部氮素总累积量分别增加3.2%和23.0%,经济效益分别增加9.7%和11.4%。施用稳定氮肥促进夏玉米对氮素的吸收累积,高量210 kg·hm-2和270kg·hm-2处理较习惯施氮提高总吸氮量。施用稳定氮肥各处理氮肥表观利用率和农学效率显著高于农民习惯施氮,偏生产力高于农民习惯施氮,生理效率除270 kg·hm-2处理外,高于农民习惯施氮。稳定氮肥施氮量在210 kg·hm-2时,能较好地协调玉米高产与稳定氮肥合理利用的统一。     

氮肥形态和地膜覆盖对坡耕地玉米产量和土壤氮素流失的影响

采用二因素四水平随机区组试验设计,利用模拟径流小区观测的方法,研究氮肥形态和覆盖对坡耕地玉米产量及土壤氮素流失通量及途径的影响。结果表明:土壤径流以地表径流为主,氮素主要流失途径是地下径流,占总径流量的71.3%,氮素流失的主要形态是硝态氮,占无机氮的92.0%,占水溶性总氮的57.1%。地膜覆盖降低径流深和土壤侵蚀量,增加水溶性氮流失量,提高玉米产量,但是酰胺态氮肥和缓控释肥地膜覆盖可降低氮素流失量,且酰胺态氮肥对玉米增产效果显著;裸地条件下硝态氮肥和缓控释肥可降低地下径流深和氮素流失量,且缓控释肥对玉米增产效果显著。综合考虑水土流失治理和粮食增产增收,四川紫色坡耕地适宜肥料类型为缓控释肥,其次是硝态氮肥,酰胺态氮肥通过地膜覆盖也能较好地控制氮素流失和增加玉米产量。     

Soil Organic Carbon and Nitrogen Fractions under Different Land Uses and Tillage Practices

Many questions have surfaced regarding long-term impacts of land-use and cultivation system on soil carbon (C) sequestration. The experiment was conducted at Ohio Agricultural Research and Development Center. Only minor variations of soil organic carbon (SOC) and nitrogen (N) fractions with depth under plow tillage (PT). The SOC, total nitrogen (TN), microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) concentrations were higher under grassland and forestland in the top 0–15 cm depth than arable soils. No-tillage (NT) also increased SOC and N fractions concentrations in the surface soils than PT. Compared to arable, grass and forest could significantly improve proportions of MBC and MBN, and reduce proportions of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). NT and forest also increased the ratio of SOC/TN, MBC/MBN, and DOC/DON. Overall, grass and forest provided more labile C and improved C sequestration than arable. So did NT under arable land-use.     

应用15N示踪技术研究耕作方式对甘蔗氮肥吸收利用的影响

为探讨甘蔗适宜的机械耕作方式,以甘蔗品种桂糖42号为材料,采用田间微区¹⁵N示踪技术,研究深松45 cm+旋耕25 cm(T1)、深翻40 cm+圆盘耙碎土25 cm(T2)和旋耕25cm(T3)3种耕作方式对氮肥利用效率及去向的影响。结果表明,3种耕作方式下新植蔗吸收的N有43.40%~46.45%来自当季施用的氮肥,氮肥利用率、残留率和损失率范围分别为14.39%~18.43%、50.70%~55.49%和26.08%~34.91%;宿根蔗吸收的N来自上季施用氮肥的比率为13.27%~14.78%,上季氮肥在宿根季的利用率、残留率和损失率范围分别为7.79%~10.35%、31.41%~34.12%和11.02%~11.50%;两季甘蔗收获后,氮肥残留均随土层深度的增加而明显递减,但T3在0~20 cm土层残留较多,其他耕作方式在20~60 cm土层残留较多。两季甘蔗干物质积累量、肥料氮来源比率、氮肥利用率及氮肥残留率以T1最高,T2次之,T3最低,T1与T3间差异达显著水平;两季甘蔗氮肥损失率以T3最高,T2次之,T1最低,其中在新植蔗3个处理间的差异达显著水平。综上,在红壤旱地,深松深翻能促进甘蔗对氮肥的吸收,减少氮肥损失,增加甘蔗产量,其中深松45 cm+旋耕25 cm(T1)的耕作方式效果较好。本研究结果可为红壤蔗地合理耕作提供科学依据。     

不同耕作模式对东北风沙土区玉米产量及氮素利用率的影响

研究优化集成耕作模式对东北风沙土区玉米产量、肥料氮素利用率及去向的影响,探讨不同耕作模式下玉米产量及氮肥利用率之间的关系,为东北风沙土区玉米生产合理耕作模式的选择提供科学依据。在东北风沙土区传统耕作模式(CT)、优化集成耕作模式1(ITP1)和优化集成耕作模式2(ITP2)小区内设置~(15)N标记微区框栽,以CT处理为对照,研究ITP1和ITP2耕作模式下玉米产量、氮肥利用率及肥料氮去向。结果表明:2种优化耕作模式玉米籽粒产量显著高于传统耕作模式,分别增产30.10%和15.53%。3种耕作模式氮肥利用率介于27.10%～35.46%,ITP1处理和ITP2处理氮肥利用率分别为35.46%和31.40%,比CT处理分别提高了30.85%和15.87%。与CT处理相比,IPT1处理氮肥残留量增加18.67%,损失量降低45.65%;IPT2处理肥料氮残留量介于IPT1和CT处理之间,差异不显著,IPT2氮肥损失率比CT处理降低24.36%,比IPT1增加39.17%。2种优化集成耕作模式增加玉米产量,提高氮肥利用率,减少氮肥污染,IPT1和IPT2两种优化耕作模式适合东北风沙土地区玉米种植。