不同施肥措施对洞庭湖区旱地肥力及作物产量的影响

应用长期定位试验方法,研究了洞庭湖区非粮食作物棉花-油菜轮作下,农民习惯施肥(TF)、配方施肥(NPK)及有机肥和化肥不同配比模式[有机肥来源氮占配方肥总氮量的50%(50%OM)、30%(30%OM)和10%(10%OM)]的作物产量和土壤养分的变化,以期为相应作物种植制度下的合理施肥提供参考。研究结果表明:在本试验施肥量及有机无机肥配比下,有机肥和化肥配施显著提高了棉花和油菜的产量,且以50%OM处理产量最高,各处理产量的顺序为50%OM30%OM10%OMNPKTFCK(不施肥对照);当有机氮施用量占总氮量的50%时(50%OM处理),棉花和油菜产量分别比NPK处理高24.52%、29.57%,比习惯施肥(TF)处理分别高46.03%和49.07%。同时,施用有机肥各处理作物产量的年际变化均不到20%,明显小于NPK、TF和CK处理,即施用有机肥不仅能促进旱地作物高产,同时也能保证其稳产。有机肥与化肥配施能增加土壤有机质、全氮、碱解氮和速效钾含量,且以50%OM处理效果最好,与试验前比较的增加幅度分别达57.5%、38.2%、65.1%和48.1%;土壤有效磷含量有随施入磷素量的增加而增加趋势;而CK处理土壤有机质和养分含量则均呈逐年下降的趋势。各处理土壤有机质和养分含量(Y)随试验年限(X)的变化均可用方程式Y=a X+b来表示。在洞庭湖区肥力较高的旱地土壤中,合理的有机肥和化肥施用比例对保障非粮作物高产稳产和耕地地力提升尤为重要,且本试验条件下当有机肥来源氮占总施氮量的50%时能获得最佳效果。     

Erosional impacts on soil properties and corn yield on Alfisols in central Ohio

Accelerated soil erosion can impact upon agronomic productivity by reducing topsoil depth (TSD), decreasing plant available water capacity and creating nutrient imbalance in soil and within plant. Research information on soil‐specific cause – effect relationship is needed to develop management strategies for restoring productivity of eroded soils. Therefore, two field experiments were established on Alfisols in central Ohio to quantify erosion‐induced changes in soil properties and assess their effects on corn growth and yield. Experiment 1 involved studying the effects of past erosion on soil properties and corn yield on field runoff plots where soil was severely eroded and comparing it with that on adjacent slightly eroded soil. In addition, soil properties and corn grain yield in runoff plots were compared on side‐slopes with that on toe‐slopes or depositional sites. Experiment 2 involved relating corn growth and yield to topsoil depth on a sloping land. With recommended rates of fertilizer application, corn grain yield did not differ among erosional phases. Fertilizer application masked the adverse effects of erosion on corn yield. Corn grain yield on depositional sites was about 50 per cent more than that on side‐slope position. Corn plants on the side‐slope positions exhibited symptoms of nutrient deficiency, and the ear leaves contained significantly lower concentrations of P and Mg and higher concentrations of Mn and K than those grown on depositional sites. Corn grain yield in experiment 2 was positively correlated with the TSD. Soil in the depositional site contained significantly more sand and silt and less clay than that on the side‐slope position. There were also differences in soil properties among erosional phases. The soil organic carbon (SOC) content was 19\7 g kg⁻¹ in slightly eroded compared with 15\1 g kg⁻¹ in severely eroded sites. Aggregate stability and the mean weight diameter (MWD) were also significantly more in slightly eroded than severely eroded soils. Adverse effects of severe erosion on soil quality were related to reduction in soil water retention, and decrease in soil concentration of N and P, and increase in those of K, Ca and Mg. Severe erosion increased leaf nutrient contents of K, Mn and Fe and decreased those of Ca and Mg. Corn grain yield was positively correlated with aggregation, silt and soil N contents. It was also negatively correlated with leaf content of Fe. Copyright © 2000 John Wiley & Sons, Ltd.     

科学耕作与留茬改良小麦-玉米两熟农田土壤物理性状及增产效果

为了探讨不同覆盖耕作方式对农田土壤物理性状及作物产量的影响,该试验研究了免耕、常规2种耕作方式和4种留茬高度的玉米秸秆还田处理,对麦-玉两熟农田土壤含水率、容重、孔隙度以及作物产量的影响。结果表明:在0～40cm土层内,秸秆还田的集雨和保水效果显著,免耕留茬0.5m还田处理的含水率比免耕无覆盖处理增加了15.95%。秸秆还田量对0～40cm内土壤贮水量的影响不同。耕作措施显著影响了土壤容重,小麦播种前常规留茬1m还田、常规全量还田处理容重低至1.0g/cm3左右。秸秆还田能增加土壤总孔隙度、降低毛管与非毛管孔隙度的比值。单一免耕处理降低了作物产量,而免耕覆盖能增产,其留茬1m还田处理比无还田处理增产22.44%,比常规留茬0.5m还田处理高3.64%。因此,免耕留茬1m还田处理在改善农田土壤物理性状和增加作物产量方面显著,该研究可为农田管理过程中耕作措施和秸秆还田量的选择提供参考依据。     

水旱轮作制下连续秸秆覆盖对土壤理化性质和作物产量的影响

采用田间定位试验研究方法,于2008～2010连续3年研究了水旱轮作制下连续秸秆覆盖对土壤理化性质和作物产量的影响。结果表明,连续秸秆覆盖显著降低了土壤表层（05cm）容重,提高了05cm和515cm土层土壤含水量。同时连续秸秆覆盖还田还可以显著提高025cm土层土壤有机质、碱解氮、速效磷和速效钾含量。秸秆覆盖对表层（05cm）土壤养分状况的效应更明显。秸秆连续覆盖5季后,05cm土层土壤速效钾含量的增幅（7.64%～15.33%）速效磷（7.52%～10.03%）碱解氮（7.30%～8.74%）有机质（6.08%～7.53%）。秸秆覆盖还田后,可以提高作物产量。其中旱季作物（小麦、油菜）的增产效应要高于水季作物（水稻）,并且随着秸秆还田年限和用量的增加,作物的增产幅度也随之提高。起主要作用的产量构成因素是小麦、水稻的有效穗数以及油菜单株角果数和每角粒数。     

豆麦轮作区麦秸长期还田对作物产量及土壤化学性质的影响

麦秆还田对作物产量影响以及秸秆还田如何施肥是农业生产者极为关注的问题,为了明确豆麦轮作麦秆长期还田对作物产量及对土壤化学性质的影响,该文依托黑河市长期定位实验站,采用裂区试验方法,主处理为秸秆还田与不还田处理,副处理为低、中、高不同施肥水平,试验于1980年开始,轮作模式先后为麦-豆-麦和麦-豆轮作模式,通过连续38 a(1980—2018年)调查,探明麦豆轮作条件下麦秸还田及不同施肥水平对作物产量影响。结果得出:麦秸还田后种植大豆、小麦,多年产量与不还田比差异不显著(P0.05);连续施肥效果,大豆中肥区比低肥区增产7.42%～10.81%,达到差异显著水平,小麦高肥区比低肥区增产14.52%～19.33%,差异极显著(P 0.01);麦秸还田大豆增产效果,还田前期(1～6季)大豆平均产量比不还田增产5.91%,后期(7～16季)平均增产7.52%,麦秸还田小麦增产效果,还田前期(1～5季)和后期(6～16季)平均增产0.31%、0.22%,后期增产频率高;麦秆隔年还田显著增加速效钾含量,施肥可以有效增加土壤碳、氮、磷含量,但长期高肥易导致土壤酸化。     

施肥对灌漠土作物产量、土壤肥力与重金属含量的影响

有机物还田是提升土壤肥力的主要措施,但也存在造成土壤金属污染的潜在风险。为查明不同有机物还田对土壤质量及作物产量的影响,本文通过长期定位试验,研究了无肥对照、常规施化肥(氮磷配施)以及70%常规化肥与牛粪、沼渣、污泥、鸡粪、菌渣和猪粪配施对土壤理化性状、有机碳和氮的固存率、氮磷钾活化系数、作物产量及重金属含量的影响。结果表明:牛粪、沼渣、污泥、菌渣、鸡粪和猪粪与70%化肥配施虽作物产量与常规施化肥相似,但6种有机物处理土壤有机质、全氮和碱解氮含量都较常规施化肥处理显著增加,污泥、鸡粪和猪粪处理土壤全磷与速效磷含量较常规施化肥处理显著增加,而且牛粪、沼渣、鸡粪和猪粪处理的速效钾、土壤磷活化系数和土壤钾活化系数较常规施化肥处理也显著提升。牛粪、沼渣、污泥、菌渣、鸡粪和猪粪处理土壤有机碳固存率为36.42%～71.61%,较常规施化肥处理都显著提高;而其氮固存率为6.47%～49.44%,仅有菌渣处理与常规施化肥处理差异不显著,而其他处理较常规施化肥处理显著增加。长期施鸡粪和菌渣处理的土壤铜含量较常规施化肥处理显著增加,增加量分别为4.17mg·kg~(-1)和14.2mg·kg~(-1);而污泥、鸡粪和菌渣处理的土壤锌含量较常规施化肥处理显著增加,增加量分别为13.53 mg·kg~(-1)、22.60 mg·kg~(-1)和49.73mg·kg~(-1)。综上,等有机质(4 500kg×hm~(-2))的牛粪、沼渣、污泥、菌渣、鸡粪和猪粪可替代30%氮磷肥,作物产量不受影响;不同有机物培肥土壤效果为污泥、鸡粪和猪粪优于牛粪和沼渣,而沼渣的培肥效果略差。为保证土壤环境质量稳定不恶化,种植小麦时有机物铜和锌的年携入量应分别低于53.01g×hm~(-2)和221.30 g×hm~(-2),而种植玉米时应分别低于153.40 g×hm~(-2)和347.04 g×hm~(-2)。     

麦稻轮作下耕作模式对土壤理化性质和作物产量的影响

为了探明不同耕作模式对土壤理化性质和作物产量的影响,采用田间定位试验方法,于2007-2010连续4a在麦稻轮作制下开展了本试验研究。结果表明,免耕提高了耕层土壤体积质量,降低了土壤含水率。但是免耕土壤表层(0～10cm)的体积质量仍在作物适宜生长的范围内,并未对作物的生长产生不利影响。免耕促进了土壤有机质和全氮在表层土壤的富集。0～10cm土层有机质和全氮含量比翻耕处理显著增加,而>10～20cm土层上述养分含量明显低于翻耕处理。小麦季免耕土壤的碱解氮、速效磷和速效钾含量的变化趋势与有机质和全氮含量相似,而水稻季免耕处理整个耕层土壤碱解氮、速效磷和速效钾含量均低于翻耕处理。免耕显著的提高了小麦产量,但降低了水稻产量,起主要作用的产量构成因素是小麦和水稻的有效穗数。整个轮作周期的作物产量以小麦免耕水稻翻耕模式的产量较高,比小麦翻耕水稻免耕模式产量增加了5.70%。     

苏丹草—黑麦草轮作中不同施肥措施对饲草产量及土壤性质的影响

在盆栽试验条件下研究了苏丹草—黑麦草轮作中不同施肥措施对饲草产量、养分吸收及土壤性质的影响。结果表明:各施肥处理均可显著提高饲草产量,整个轮作期,单施化肥（NPK）、石灰和化肥配施（NPK+Lime）、有机肥和化肥配施（NPK+OM）处理的鲜草产量分别比不施肥处理（CK）增加6.1倍、6.8倍和7.3倍;在化肥基础上配合施用石灰和有机肥,鲜草分别增产9.5%和17.2%。养分吸收结果显示,不同施肥处理明显提高饲草N、P、K含量并促进饲草对养分的吸收。土壤养分分析结果表明,与CK及NPK处理相比,增施石灰和有机肥提高酸性土壤pH值,促使其向中性靠近;在NPK基础上配合施用石灰,轮作结束时土壤有效钙含量比NPK处理提高了20.7%,有效铁和有效锰含量降低了26.5%和41.2%;在NPK基础上增施有机肥,能显著提高了土壤中的氮、磷、钾养分含量。     

Influence of tillage on crop residue cover, soil properties and yield components of cowpea in derived savannah ectones of Nigeria

The effects of five tillage treatments: no tillage (NT), disc harrowing (DH), mouldboard ploughing followed by disc harrowing (MPH), disc ploughing followed by disc harrowing (DPH), and disc ploughing followed by two passes of disc harrowing (DPHH) on crop residue cover, soil properties and some yield parameters of cowpea were investigated for a derived savannah ectone soil. The residue left on the soil surface for NT, DH, and MPH is not significantly different. The NT left 32.1 and 44.3% more residue on the soil surface than the DPH and DPHH treatments, respectively. The NT treatment had least average value of soil bulk density of 1.01 g/cm³. The mean soil bulk densities for the DH, MPH, DPH and DPHH vary between 1.20 and 1.35 g/cm³. The soil moisture content decreased with increasing soil depth. At the soil depth of 10–30 cm, the cone penetration resistance at NT was 1.18 MPa compared with 0.92 MPa for the DH treatment, although these were not significant (p≤0.05). The tillage treatments had a significant effect on grain yield, mass of leaves and stems, root length density, and number of pods per plant of cowpea except on the germination count. DH and NT treatments gave different grain yield and number of pods per plant but these values were not statistically different and represent the highest grain yield and number of pods per plant among the other treatments were considered. The root zone exploration revealed highest root density at shallow depths with the DH and MPH treatments.     

盐碱地应用根际促生菌对土壤改良、作物产量与品质的影响——基于Meta分析

本研究搜集了1990-2021年间国内外已发表关于盐碱地根际促生菌（PGPR）应用效果的文献，利用Meta分析方法从土壤盐碱程度、PGPR的接种方式和施用菌种三个方面分析了盐碱地施用PGPR对土壤盐碱化程度、理化指标、作物产量和品质的影响。结果表明，盐碱地应用PGPR降低了土壤pH和EC，显著提高了土壤肥力（速效磷、速效钾、速效氮、全氮、有机质）、作物生理指标（叶绿素含量和抗氧化酶活性）以及作物的产量和品质。与中度和轻度盐碱条件相比，重度盐碱条件下接种PGPR对作物的增产提质效果更加明显，作物产量、类胡萝卜素、可溶性蛋白和可溶性糖含量分别增加了36.3%-57.4%、31.0%-62.5%、37.8%-60.9%和37.9%-68.6%，并且土壤接种方式比种子接种在提升作物产量方面更有优势；接种假单胞菌属PGPR对降低土壤盐碱化程度更显著，土壤pH和EC分别降低了5.2%-9.5%和7.3%-23.0%；接种芽孢杆菌属PGPR对促进作物的产量与品质效果更加明显，作物产量增加了36.5%-54.0%，类胡萝卜素、可溶性蛋白和可溶性糖含量等品质指标提高了30.0%-49.5%、26.0%-64.5%、23.0%-37.7%。通过结构方程模型发现，接种PGPR通过降低土壤盐碱程度，提高土壤肥力与作物生理指标，从而实现了增产提质效果。本研究可为改良盐碱土壤与盐碱地作物高效生产提供理论支撑。