甘蔗茎秆在扭转、压缩、拉伸荷载下的破坏试验

甘蔗茎秆物理力学特性是建立甘蔗茎秆材料模型和茎秆在各种荷载下本构关系的基础。该文以“桂林—1号”甘蔗的茎秆为试验材料,采用自制的夹具,在扭转试验机上进行扭转试验,在材料力学万能试验机上进行拉伸、压缩试验。试验结果表明：在扭转荷载下,甘蔗茎秆的破坏形式为产生轴向裂纹;在压缩荷载下的破坏形式为屈曲,并产生轴向裂纹;在拉伸荷载作用下,蔗皮、蔗芯的破坏形式为断裂。对试验用 “桂林－1号”甘蔗茎秆的基部,切变模量的平均值为10.82 MPa,最大剪切应力的平均值为0.45 MPa;基部第一、二、三节的抗压强度平均值分别为14.47 MPa、9.93 MPa和8.24 MPa。基部蔗皮轴向、径向拉伸强度平均值分别为47.02 MPa和2.57 MPa,蔗芯轴向、径向拉伸强度平均值分别为6.71 MPa和1.34 MPa。     

基于产量水平的内蒙古阴山地区马铃薯施肥评价

明确内蒙古阴山地区马铃薯施肥现状,为实现内蒙古马铃薯的稳产增产和养分高效利用提供理论依据。对内蒙古阴山地区连续 5年的调查数据进行分析,基于马铃薯产量确定合理施肥量,对农户实际施肥量进行评价,分析农户施肥存在的问题。旱地马铃薯平均产量 16.6 t/hm²,水浇地马铃薯平均产量 35.9 t/hm²,水浇地马铃薯产量明显高于旱地马铃薯。旱地马铃薯施氮量介于 0～ 363 kg/hm²,平均 103.6 kg/hm²;施磷量介于 0～ 354 kg/hm²,平均 75.9 kg/hm²;施钾量介于 0～ 330 kg/hm²,平均 46.0 kg/hm²。水浇地马铃薯施氮量介于 45～ 471 kg/hm²,平均 224.5 kg/hm²;施磷量介于 0～ 393 kg/hm²,平均 172.4 kg/hm²;施钾量介于 0～ 414 kg/hm²,平均 167.7 kg/hm²。马铃薯的产量和施肥量变异均很大,且氮、磷和钾用量与马铃薯产量不同步。不管是旱地马铃薯,还是水浇地马铃薯,当产量水平由低到高,施氮过量的农户总的趋势是降低的,施氮量适中的农户比例逐渐增加,施氮不足的农户比例逐渐增多;施磷量分布趋势与不同产量水平施氮量分布类似;农户施钾不平衡主要表现为施钾不足。内蒙古阴山地区有 71.6%的农户不施有机肥,且有机肥施用量很低,平均 7.1 t/hm²。内蒙古阴山地区马铃薯养分管理存在的主要问题是化肥施用过量和不足并存,有机肥施用量偏低。     

氮、磷、钾配施对葛根生长及品质的影响

为探明氮、磷、钾肥配施对葛根生长及品质的影响,为葛根高效栽培提供合理的施肥技术支撑和理论依据,采用L9(34)正交试验设计,研究氮、磷、钾配施对葛根产量和主要功能成分的影响,明确研究区葛根氮、磷、钾的最佳施用量。结果表明,不同施肥方案对葛根产量和功能成分的影响显著,其中以N3P1K2(N 270kg/hm²,P2O5 45 kg/hm²,K2O 90 kg/hm²)处理的产量和总黄酮含量最高,分别为2.13 kg/ 株和83.10 mg/g;N1P3K2(N 90 kg/hm²,P2O5 135 kg/hm²,K2O 90 kg/hm²) 的葛根素含量最高, 为24.85 mg/g,N1P2K3(N 90 kg/hm²,P2O5 90 kg/hm²,K2O 135 kg/hm²)处理的大豆苷和大豆苷元含量均为最高,分别为22.96 和2.55 mg/g。氮、磷、钾肥配施对葛根产量和葛根素含量影响的大小顺序为氮肥> 钾肥> 磷肥。以葛根产量为目标的最佳施肥量为N 270 kg/hm²、P2O5 135 kg/hm²、K2O 90 kg/hm²,以葛根品质提升为目标的最佳施肥量为N 180 kg/hm²、P2O5 135 kg/hm²、K2O 90 kg/hm²。     

第四纪红色粘土发育的红壤中营养元素的淋失

A red soil derived from Quaternary red clay was employed to study nutrient leaching with soil columns repacked in laboratory. The objective was to identify the effects of fertilization practices on leaching patterns and magnitudes of Ca²⁺, Mg²⁺, K⁺, NH₄⁺, and NO₃^-. The treatments were CK (as a control), CaCO₃, CaSO₄, MgCO₃, Ca(H₂PO₄)₂, urea, KCl, and multiple (a mixture of the above-mentioned fertilizers). The fertilizers were added to the bare surface of the soil columns, and then the columns were leached with 120 mL deionized water daily through peristaltic pumps over a period of 92 days. Leaching processes of NH₄⁺, and NO₃^- were only measured in CK, urea, and multiple treatments which were directly related to N leaching. Results showed that sole application of CaSO₄, and Ca(H₂PO₄)₂ scarcely had any effect on the leaching losses of Ca²⁺, Mg²⁺, and K⁺; the application of MgCO₃ stimulated the leaching of Mg²⁺; the application of CaCO₃ promoted the leaching of Ca²⁺, Mg²⁺ and K⁺; urea treatment also promoted the leaching of K⁺ and NH₄⁺, and NO₃^- leaching mainly occurred at late stage of leaching process in particular; under KCl treatment, leaching of Ca²⁺, Mg²⁺, and K⁺ was promoted to a large extent; under multiple treatment, leaching of Ca²⁺, Mg²⁺, K⁺, NH₄⁺, and NO₃^- was all increased and NO₃^- was mainly leached at the end of leaching process and still had a trend of increase.     

沼液与有机肥配施对稻田磷、钾素径流损失的影响

研究沼液、有机肥配施对稻田磷、钾损失的影响,拟明确降低稻田磷、钾元素损失的最佳配施措施。以太湖水稻土为研究对象进行盆栽试验,设置了空白对照(CK)、常规化肥(CF),100%沼液氮替代(N1),75%沼液 +25%猪粪有机肥氮替代(N2),50%沼液＋ 50%猪粪有机肥氮替代(N3)和 100%猪粪有机肥氮替代(N4)6个处理,测定施肥后稻田田面水以及径流磷、钾浓度和流失量。结果显示,各施肥处理径流磷损失量大小依次为N4>N3>N1>CF>N2,其中 N4处理最高,达到 P 44.99 kg/hm²,N2处理最低,为 P 3.94 kg/hm²,仅为前者的8.76%;各施肥处理径流钾损失量大小依次为N1>N3>N4>N2>CF,最高为 N1处理的 K 43.48 kg/hm²,最低为 CF的 K 24.78 kg/hm²;各施肥处理产量无显著差异,处于同一水平。综合比较而言,N2处理可在保持一定产量的基础上显著降低径流磷、钾流失的风险,是一种比较适宜的施肥模式。     

重庆市花椒生产的产量差及影响因素分析

基于重庆市2017年以来的225份调研数据,以产量数据前5%的平均值为产量潜力,产量水平为分类依据,分析当前小农户生产的施肥现状、产量差及其影响因素、化肥减施潜力,以期为区域花椒生产增产增效提供参考依据。重庆花椒平均产量为8.66 t/hm²,产量潜力为16.7 t/hm²,产量差达8.02 t/hm²,当前椒农平均生产水平仅实现了产量潜力的52%,高、中、低产农户的产量差分别为3.11、7.84、12.2 t/hm²;椒园氮、磷、钾化肥用量分别为N 283 kg/hm²、P2O5 182 kg/hm²、K2O 237 kg /hm²。高产组椒农的化肥减施潜力大,其氮、磷和钾肥可分别减施36%、19%和16%;农户平均施肥以及中、低产组农户施肥水平均低于线性-平台模型拟合的合理施肥量,高产组农户是化肥减量和效益提升的主要对象。当前生产条件下,优化施肥量(氮肥N 299 kg/hm²,磷肥P2O5 228 kg/hm²,钾肥K2O 307 kg/hm²)、施肥次数(4～5次)、种植密度(密植,2000株/hm²以上)和整枝管理(果枝长度1.5 m以上,单株结果枝条数47～48条/株)能有效削减花椒产量差15.4%～43.3%;其中,施肥量、施肥次数和种植密度是影响花椒产量的主要因素,三者的贡献率高达52%。综上所述,重庆花椒生产上农户间产量、施肥量差异较大,提升农户科学施肥认识、整枝管理水平、耕地保护意识以及合理密植观念有利于削减花椒产量差和提高花椒生产效率,同时助力农业可持续发展。     

几种甘蔗品种残体量及其养分含量

广西主栽甘蔗品种通过桶栽法研究甘蔗叶、根茬、蔗头、尾梢等残体的量,探讨这些残体与甘蔗茎产量的比例关系以及这些残体所含有的NPK养分.结果表明,甘蔗品种之间其全部残体的量是因品种而异,甘蔗全部残体干重与蔗茎产量鲜重之比为0.167～0.294;甘蔗叶在全部残体中占71.36%,是甘蔗鲜重产量的11.9%～20.7%,叶干重所占单株全部残体的比例最大,根次之,达18.29%,第三为蔗头,占6.37%,而尾梢最低,仅为4.02%;甘蔗收获时干叶、青叶、尾梢、蔗根、蔗头的含N平均值分别为5.92、6.16、7.29、3.87、3.16 g/kg,而磷(P)含量平均值分别为0.65、1.01、2.27、0.59、0.66 g/kg,钾(K)含量平均值分别为6.24、9.11、21.97、5.71、4.92 g/kg;充分利用好这些残体,有助于提高蔗地土壤有机质含量和养分循环利用.     

具啄田菁茎瘤的固氮作用

具有固氮作用的茎瘤豆科植物约有三种,即含羞草亚科素食假含羞草属的素食假含羞草(Neptunia oleracea)^[1];蝶形花亚科合萌属的合萌(Aeschynomene indica)^[2,3];和具啄田菁(Sesbania rostrata)^[4]。     

氮、磷、钾配施对胡麻产量的影响及推荐施肥量研究

为了揭示氮、磷、钾肥配施对胡麻生长的影响,采用“3414”不完全正交回归设计,研究了3种施肥梯度下胡麻经济性状、产量、增产率、肥料贡献率和产投比等的变化,并进行胡麻产量肥效模型函数拟合。结果表明:低氮、磷、钾和中氮、磷、钾施肥水平有利于提高胡麻经济性状指标;施氮、磷、钾处理下胡麻产量较不施氮、磷、钾肥处理提高了4.95%～24.07%,胡麻产量随着施肥量的增长呈现出先增高后降低的趋势,当氮(N)、磷(P2O5)、钾(K2O)分别为75、67.5、72 kg/hm²时胡麻产量最高;钾肥对胡麻产量的贡献大于氮肥和磷肥,高磷具有明显的减产效应;通过肥料效应函数拟合分析,本试验条件下推荐最高施肥量为:N 69.1 kg/hm²,P2O5 51.5 kg/hm²,K2O 63.4 kg/hm²,最佳施肥量为:N 39.6 kg/hm²,P2O5 26.5 kg/hm²,K2O 25.7 kg/hm²。     

甘蔗等高种植与新植配置比例对坡面沟蚀引起的氮磷养分流失的影响

[目的] 探讨甘蔗等高种植与新植适宜的配置比例,为甘蔗种植区减少坡面沟蚀和养分流失、提升耕地质量和合理种植甘蔗提供技术支撑。[方法] 通过野外测量与试验分析相结合,确定苗期、分蘖期、伸长期和成熟期4个甘蔗生长时期内低、中、高3种等高种植和新植比例的甘蔗坡面沟蚀量和养分流失量,并明确其影响因素。[结果] ①整个甘蔗生育期,那辣流域甘蔗种植坡面沟蚀及其导致的全氮、全磷流失量分别在31.3～66.3 t/hm²,39.0～82.5 kg/hm²,18.0～38.4 kg/hm²之间; ②苗期是那辣流域沟蚀和养分流失的主要时期,其贡献量占甘蔗全生育期的比例为47.7%～57.7%。③全生育期,高比例等高(H_C)的坡面沟蚀和养分流失比低比例新植坡面(L_C)低33.03%～35.42%(p＜0.05),但中比例等高(M_C)和H_C,L_C的流失量均不显著;低比例新植(L_Rp)坡面沟蚀和养分流失量比高比例新植(H_Rp)低27.41%～32.98%,比中比例新植(M_Rp)低21.02%～25.86%(p＜0.05),凋落物覆盖度和根系密度是影响沟蚀与养分流失的重要因素。④全生育期,坡面全氮和全磷流失量分别占年氮肥和磷肥施用量的24.1%～39.5%和107.0%～156.7%。[结论] 在甘蔗种植时,60%以上的等高种植比例和30%以下新植比例,可以有效减少坡面土肥流失。     

茎秆作物抗倒伏生物力学评价研究及关联分析

研究茎秆作物的生物力学性质可为相关作物机械化生产及产品深加工等作业装备提供设计参数,还能对茎秆作物优种筛选进行评价指标。该文在高秆、中秆和矮秆3个品种,4个不同生长期的小麦茎秆弯折性能试验,2个玉米品种灌浆高峰期弯折性能试验,2个高粱品种灌浆高峰期弯折性能试验,2个大豆品种结荚鼓粒期弯折性能试验数据的基础上,进行了茎秆作物抗倒伏特性的生物力学评价指标研究及关联分析。采用灰色关联法分析了不同生长期惯性矩、弹性模量、抗弯刚度、抗弯强度等与弯折性能有关的各生物力学指标与抗倒性之间的关系,并以小麦茎秆为例对评价指标进行了权重数确定和检验。结果表明：茎秆作物不同品种茎秆生物力学性能指标中的弹性模量、抗弯折强度和惯性矩对倒伏的影响程度基本相当,抗弯刚度对倒伏影响较小。该结论为茎秆作物生物力学评价提供了新的途径和方法。     

Nitrogen doses on physiological attributes and yield of sugarcane grown under subsurface drip fertigation

Soil hydric availability and nitrogen fertilization are important environmental factors that influence sugarcane production. In the present study, the physiological attributes SPAD index, maximum photochemical efficiency of photosystem II (F_v/F_m), leaf area index (LAI), chlorophyll and carotenoid content, and sugarcane productivity were assessed under different nitrogen doses (0, 50, 100, 150, and 200 kg N ha^?1) applied in the form of urea via subsurface drip fertigation. The physiological attributes were determined 38, 121, 208, 291, and 381 days after the third harvest (DAH), and stalk and sugar productivity at 381 DAH. The 100 kg N ha^?1 dose has produced better results for the sugarcane physiological attributes. Increasing doses of nitrogen applied via subsurface drip fertigation increased the productivity of stalks and sugar considerably.     

收割期芦竹底部茎秆机械物理特性参数的试验研究

试验研究芦竹底部茎秆的机械物理特性,以获得其最大破坏应力、弹性模量等机械物理特性参数,并分析芦竹切割过程中应力、应变分布状态,能为芦竹切割刀具和切割方式的设计提供理论依据和基础技术参数,对低能耗、高效率的芦竹切割器的设计具有重要的指导意义。该文利用微机控制电子万能材料试验机对收割期的芦竹底部的茎秆进行了顺纹拉伸、压缩、弯曲试验,获得试验条件下顺纹拉伸、压缩、弯曲的应力－应变曲线,并进行了分析。试验测得芦竹底部茎秆顺纹拉伸最大抗拉强度平均值为123 MPa,弹性模量值为1260 MPa;顺纹压缩最大抗压强度平均值为52 MPa,弹性模量值为595 MPa;顺纹弯曲最大抗弯强度平均值为125 MPa,弹性模量值为1715 MPa。结果表明,芦竹破坏应力参数接近毛竹,远大于玉米、小麦等茎秆的破坏应力参数,芦竹的机械化收割不宜采用传统的切割器。     

谷子茎秆叶鞘叶片及其结合部位的拉伸力学性能

针对谷子机械收获作业过程中存在的秆叶易缠绕问题,该研究以晋谷21、张杂10为对象,分别对谷子不同节间的茎秆、叶鞘、叶片和叶环各部位进行拉伸力学测试,并利用SAS统计软件对测试数据做分析,在此基础上分析了相关力学参数沿茎秆节间的变化规律。2个谷子品种的茎秆在上下节间处的弹性模量、抗拉力和抗拉强度均差异显著(P<0.05)。由茎秆表皮拉伸测试测得晋谷21的茎秆弹性模量为4.15～6.64 GPa,抗拉强度为67.65～130.13 MPa,抗拉力为343.97～1 598.37 N;张杂10的茎秆弹性模量为4.54～7.98 GPa,抗拉强度为73.22～136.50 MPa,抗拉力为167.66～567.54 N。2个谷子品种在不同节间位置、不同部位(叶鞘、叶片及叶环)的抗拉力和抗拉强度差异均极显著(P<0.01)。晋谷21的中上部节间叶鞘、叶片及叶环平均抗拉强度分别为13.30、10.13和4.18 MPa,平均抗拉力分别为122.16、41.23和25.80 N。张杂10的中上部节间叶鞘、叶片及叶环平均抗拉强度分别为13.30、11.77和4.24 MPa,平均抗拉力分别...     

棉秆挤压剥皮剪切力学特性试验

针对棉秆重组材原料疏解剥皮的需要,该文利用自制的棉秆剥皮试验台,以测试剥皮剪切强度为目标,对含水率、取样部位、加载强度3个影响因素进行了中心组合试验,对皮附着长度进行了单因素试验,并将泡水软化棉秆和新鲜棉秆进行了比较.结果表明:取样部位、加载强度对轴向与切向剥皮剪切强度影响显著(P＜0.01);含水率对轴向和切向剥皮剪切强度的影响不显著(P＞0.05),三因素间的交互作用均不显著(P＞0.05);加载强度、取样部位、含水率对棉秆剥皮剪切强度的影响依次由强到弱;切向剥皮方式优于轴向剥皮方式;新鲜棉秆的剥皮剪切强度较小,收获后及时剥皮效果好.该研究可为棉秆疏解剥皮装备的设计提供参考.     

Soil Fertility,Sugarcane Yield Affected by Limestone,Silicate, and Gypsum Application

The aim of this study was to verify if the application of silicate or lime, in association with gypsum, on sugarcane residue can lead to amendment of subsurface soil acidity, increasing sugarcane yield and profitability. The treatments were: 1 – control (without application of amendments), 2 – gypsum, 3 – dolomitic limestone, 4 – silicate, 5 – dolomitic limestone + gypsum, and 6 – silicate + gypsum. The surface application of gypsum led to reduction in Al (aluminum) contents and Al saturation, and increase in Mg⁺², Ca⁺², K⁺, S–SO₄^?, and base saturation in deeper soil layers, as well as increased yield of stalks, sugar, trash, bagasse, and energy, and greater profit. The application of limestone and silicate, alone or in association with gypsum, amend soil acidity throughout the soil profile. It likewise leads to an increase in stalk, sugar, trash, bagasse, and energy yield, however, application of silicate in association with gypsum leads to the greatest profitability.     

苎麻茎秆力学模型的试验分析

为了提供苎麻收割、剥制机械研究设计的力学参数及理论基础,论文对苎麻茎秆的几何形状进行假定,运用复合材料力学理论建立苎麻茎秆力学模型,利用微机控制万能试验机对苎麻茎秆各向(轴向、径向)及各组分(木质部、韧皮部和茎秆整体)进行拉伸、压缩、弯曲等力学试验,获得力学参数数据,并通过数据的分析计算获得苎麻茎秆力学模型的全部弹性参数。同时,试验结果表明,苎麻茎秆在轴向拉伸中表现更多为木质部的承载作用,其韧皮部与木质部的粘附力不能阻止韧皮部沿木质部表层滑移;苎麻茎秆径向弹性参数测量值和通过各组分弹性参数值计算获得的计算值接近,苎麻茎秆径向符合复合材料的特性。     

不同浓度乙烯利处理对甘蔗经济性状的效应

在甘蔗的分蘖初期用不同浓度的乙烯利处理，结果表明：５０ｍｇ／Ｌ，１００ｍｇ／Ｌ浓度的乙烯利处理明显促进了甘蔗前中期的生长，改善了甘蔗的经济性状，使蔗茎的节间长度、茎长、茎径、单茎重及有效茎数均有所提高，获得显著的增产效果，并且明显提高了甘蔗的蔗糖分及品质．     

Sugarcane response to saline irrigation water

Salinity of irrigation water reduces yield and juice quality in sugarcane (Saccharum spp. hybrids), but cultivars vary in the degree of reduction. Genotypes which accumulate more potassium (K⁺) may be more resistant to salinity than genotypes that accumulate less K⁺. We examined the effect of irrigation water salinity on yield and juice quality in a cultivar with high conductivity, high K⁺ juice, ‘NCo 310’, and a cultivar with low conductivity, low‐K⁺ juice, ‘TCP 87–3388 ‘. Plants were grown in lysimeters containing 793 L of soil and irrigated with water of 0.01, 1.25, 2.93, or 4.70 dS m^‐1. Quality and component analyses were conducted on the juice of single stalks subdivided by length, and the juice from whole stalks. The two cultivars responded similarly to increased salinity, although juice of NCo310 had a higher mineral concentration, especially K⁺ and Cl^‐. Yield and most quality components were not significantly reduced by 1.25 dS m^‐1 water. The 2.93 and 4.70 dS m^‐1 treatments reduced stalk height and weight but not stalk numbers. The reduction in stalk height was due to decreases in number of internodes per stalk and mean internode length. Increasing salinity reduced total soluble solids and sucrose in juice, but increased Na⁺, K⁺, Mg⁺², Ca⁺² and Cl^‐ Within a stalk, sucrose increased from top to bottom, while K⁺ decreased. Sodium concentrations were sharply higher in the lowest section, especially in plants irrigated with saline water. Chloride concentration was approximately equal in all sections. An increase in K accumulation did not appear to increase the salt tolerance of NCo310.