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1.
滴灌条件下灰枣施肥效应研究   总被引:1,自引:0,他引:1  
以滴灌为条件设置不同水肥处理,通过施肥模型建立与分析,研究氮磷钾施肥配比对灰枣产量与品质的影响。结果表明:在设计水平范围内,土壤中适量增施氮、磷肥能提高灰枣果实单果重和产量;增施钾肥可提高枣果中还原糖和Vc的含量,增施氮肥则可提高蛋白质的含量;氮、磷、钾三因素对灰枣产量以及糖度、Vc含量的作用顺序为:施钾量〉施磷量〉施...  相似文献   

2.
谭子祎  张华  辛海波 《农业工程》2021,11(9):119-123
为明确N、P、K元素对苹果炭疽叶枯病菌的影响,研究了不同浓度NaNO3、NaH2PO4、KCl对炭疽叶枯病菌的影响。结果表明:3种药剂提供的不同浓度的N、P、K元素对病菌既有抑制作用,又有促进作用。①5 g/L的N元素处理抑制效果最好,抑制率为29.49%。②1 g/L的P元素处理对病菌有轻微抑制作用,抑制率为2.56%。③37 g/L的K元素处理对病菌有一定抑制作用,抑制率为5.13%。④5 g/L的K元素处理对病菌的促进作用最高。⑤5 g/L的N+1 g/L的P和5 g/L的N+37 g/L的K组合对病菌抑制效果较好。整体数据来看,3种元素不同浓度处理对炭疽叶枯病菌的影响效果差异大,N整体抑制效果明显大于P、K的抑制效果,N+P和N+K的组合抑制效果较好。   相似文献   

3.
水氮互作对盆栽番茄生长发育和养分累积的影响   总被引:5,自引:0,他引:5  
为探讨不同水氮供应对番茄生长发育和养分吸收的影响,以日光温室盆栽番茄为研究对象,研究3种灌溉水平(灌水下限分别控制在田间持水率的50%、65%、80%,分别记为I1、I2和I3)和4种施氮水平(N和土壤质量比为0、0. 13、0. 27、0. 40 g/kg,分别记为N0、N1、N2和N3)对番茄生长发育、生物量、组织含水率和养分累积量的影响。结果表明:叶面积、茎粗和株高均随灌水量的增大而显著增大,随施氮量的增大呈显著的先增大后减小趋势,且N1时各灌溉水平的生长指标均最优;茎和叶含水率在各处理间无明显规律,而果实含水率随灌水量的增大而显著增大,随施氮量的增大而显著减小;茎、叶和果实的干物质量均随灌水量的增大而极显著的增大,随施氮量的增大呈先增大后减小趋势,N1最有利于干物质的形成;水分胁迫(I1)条件下增施氮肥有助于各组织对全氮(N)、全磷(P)和全钾(K)的吸收,且养分更多的用于生殖生长,各组织对养分吸收的施氮阈值为0. 13 g/kg(N1);地上组织N、P、K累积量与干物质量呈极显著正相关,与对应的养分含量呈显著的负相关(N和K除外),与组织含水率的相关性不显著,且N累积量与P、K累积量均呈极显著的正相关,故增施氮肥可以促进番茄对养分的吸收,特别是促进对K的吸收。与N1I3处理相比,N1I2的果实干物质量、N累积量和K累积量分别下降了3. 04%、10. 67%和12. 08%,但可节约用水25%,因而灌溉控制下限为田间持水率的65%(I2)和施氮水平为0. 13 g/kg(N1)为最优水氮组合模式,可实现节水、省肥功效,合理调控株型,为产量形成和品质的优化奠定基础。  相似文献   

4.
滴灌施肥对加工番茄产量和品质的影响   总被引:1,自引:0,他引:1  
为了寻求滴灌施肥条件下连作加工番茄持续优质高产平衡施肥方案,以番茄为材料,采用"3414"优化试验方法,分析了滴灌平衡施肥对加工番茄生长发育、产量和品质的影响。结果表明,滴灌施肥条件下,增施氮、磷、钾肥和配施微肥明显促进番茄生长发育;增磷和配施微肥显著提高产投比,实现增收;增氮、增钾的增产效果不显著,但减氮、减钾显著降低了产量;增钾、配施微肥显著提高加工番茄品质,尤其在提高番茄糖酸比,降低硝酸盐量积累,促进可溶性固形物的形成及改良色差等方面成效显著。滴灌施肥条件下,增施磷、钾肥,配施微肥对连作加工番茄具有显著的增产提质作用。  相似文献   

5.
为寻找利于番茄高产高质的合理灌水施肥组合,在水肥一体化条件下,采用正交试验和模型预测探究不同灌水下限、施氮量、施钾量对番茄生长、产量和品质的影响。试验结果表明:提高灌水下限,可以增加茎粗和叶面积;大量施入氮肥不利于茎粗的增加,但对于增加番茄叶面积有促进作用;钾肥施入量对番茄茎粗、叶面积均无显著影响。在生育前期适当的增加灌水和减少氮肥施入量,有利于植株的生长。灌水下限、施氮量和施钾量均对番茄产量具有显著影响,且随灌水施肥量的增加,产量呈现先增加后减少的趋势。经评分法分析,W2N2K2水肥组合可以得到最优品质。通过模型精确预测,得出在灌水下限为76%,施氮量358.5 kg/hm2,施钾量607.5 kg/hm2时,产量最高、品质优,作物生长良好,预测产量为108.82 t/hm2。  相似文献   

6.
夏黑葡萄增施钾肥对比试验初报   总被引:1,自引:0,他引:1  
试验以夏黑葡萄为研究对象,通过增施钾肥对比试验,研究增施钾肥对葡萄生长、产量、品质和经济效益的影响。试验结果表明:增施钾肥对葡萄生长、产量和品质都产生了有利影响;与不施钾肥(对照)相比,在果实膨大期和着色期每667 m~2各增施25 kg钾肥处理生育进程加快,产量增加最高,每667 m~2增加118.5 kg,经济效益也最高,每667 m~2增加4 354元。  相似文献   

7.
研究了长白山区沟谷沼泽乌拉苔草不同构件元素含量及叶片不同季节积累变化及元素间的相互关系。结果表明,乌拉苔草属于抗金属污染植物,不同构件在元素积累和季节变化中有较大差异:Mn、N,P、Mg、Fe、Cu、Zn主要集中在根部,K主要集中在叶鞘。不同季节积累中,N、K主要在营养成长期和生殖生长并存期5月份最多,P在成熟期的8月份最多,金属元素在衰老期的9月份最多,尤其是Fe元素富集量最多,完全可以作为铁污染区的抗性植物和净化植物,而非金属元素在衰老期的9月份最少。金属元素之间相生相互协调关系强,非金属元素之间关系相互协调,而金属元素除Mn和P、N是极显著相关外,P和Ca呈显著相关,与其他关系不显著。说明乌拉苔草各构件中的元素之间没有相互拮抗的关系。  相似文献   

8.
为探明水肥施用量对夏玉米生长的影响,在山东省灌溉试验中心站开展田间小区试验,对比研究不同水(70.5 mm、125.5 mm,记为I1、I2)、不同供氮(145、195、245kg/hm~2,记为N1、N2、N3)与供磷(60、95、120kg/hm~2,记为P1、P2、P3)条件下的夏玉米生物学特性和产量。结果表明:水肥管理对夏玉米株高、叶面积指数(LAI)、产量的影响较大,其差异达到了显著水平(P0.05),灌水较施肥对其影响更为显著;在灌水量一定的条件下,夏玉米株高、叶面积指数与产量都随着氮磷施用量的增加先增加后减少,I2N2P2处理更有利于夏玉米的生长。相同的灌溉量与相同施氮(磷)量下,干物质最大增长速度随着增施磷(氮)肥量先增大后减小,最大增长速度出现的时间随着增施磷(氮)肥量先提前后推迟;通过线性拟合得出在一定范围内株高、叶面积指数和干物质积累量对夏玉米产量的增加具有正相关性。I2N2P2处理下的氮磷肥偏生产力较其他处理较高。综上分析得在I2N2P2处理下夏玉米各生长要素和产量得到最优值。  相似文献   

9.
施肥对免耕旱作燕麦田土壤温室气体排放的影响   总被引:1,自引:1,他引:0  
采用静态箱-气相色谱法,研究了不施肥(CK)、施氮肥(N)、施磷肥(P)、施钾肥(K)、氮磷肥配施(NP)和氮磷钾肥配施(NPK)5种施肥处理对免耕旱作燕麦田土壤温室气体排放的影响,以期为当地农田生态实现可持续发展提供科学依据。结果表明,各处理土壤CO_2排放通量随燕麦生育期均呈先增加后减小的趋势,拔节期出现峰值;不同施肥处理CO_2平均排放通量均高于不施肥处理,其中氮磷钾配施、氮磷配施和施氮处理与不施肥处理间差异显著;各处理土壤CH_4排放通量在全生育期内均表现为吸收特征,呈"反S型"变化,全生育期氮磷钾、氮磷和施氮处理CH_4平均吸收通量显著高于不施肥处理,分别是不施肥处理的1.30、1.25、1.15倍,三者之间差异不显著;各处理N_2O排放通量全生育期内均表现为排放源,呈先增后减的趋势,各处理N_2O平均排放通量表现为施氮氮磷配施氮磷钾配施施磷施钾不施肥,其中施氮、氮磷配施、氮磷钾配施与不施肥处理差异显著,施磷、施钾与不施肥处理差异不显著;氮磷钾配施、氮磷配施、施氮、施磷、施钾处理综合温室效应分别比不施肥处理高22.3%、15.6%、12.8%、10.1%和4.7%,除施钾处理外,其他施肥处理均与不施肥处理差异显著。  相似文献   

10.
研究灌水量和氮、磷、钾肥用量对番茄产量和水分利用效率的影响,为番茄的高效生产提供依据。以"金鹏1号"番茄为试验材料,采用盆栽试验,对不同灌水量和氮、磷、钾肥用量条件下的番茄产量和水分利用效率进行分析。结果表明,灌水量增加,番茄产量和灌溉水利用效率先增后降。增施氮肥或钾肥,番茄产量和灌溉水利用效率呈先增加后降低趋势,当施氮量或施钾量达最高水平(分别为0.96g N/kg土、0.84g K2O/kg土)时,番茄产量和灌溉水利用效率均最低。施磷量增加,番茄灌溉水利用效率明显增大。增加灌水量能显著提高番茄产量,灌水过多导致减产,且灌溉水利用效率下降,造成水分的浪费。合理施用氮、磷、钾肥不仅能起到增产的效果,在一定程度上还能改善番茄水分状况,提高番茄灌溉水利用效率。  相似文献   

11.
针对化探样品批量大,元素多,检出限低等特点,采用水平电极撒料法,对化探样中多种微量元素进行了光谱定量分析.将样品与缓冲剂1:1混匀,采用W-100光栅摄谱仪(光栅刻线1200条/毫米,二级光谱)进行水平撒样摄谱,谱板经暗室处理后,在东德GFE760μ测微光度计上用P标尺测光,以△P-logc绘制工作曲线,查出含量.本法采用了特制的撒样漏斗,改善了下料的均匀性,提高了分析精度;以Ge和Pd作内标消除工作条件变化对谱线强度的影响;同时还试选了SiO2:C:Na2SO4=61:30:9的混合物作缓冲剂,提高了弧烧的稳定性,获得了较高的再现性.本文还采用了一种单元素线减光器对Ag3382.9进行减光,使Ag的测定上限由5×10-6提高到30×10-6.本法操作简便快速,成本较低,一次可测定Ag、W、Mo、Sn、Bi、Cu、Pb、Zn、Ni、Co、Cr等多种元素,检出限为Ag 0.03×10-6,W 0.5×10-6,Mo0.05×10-6,Sn 0.4×10-6,Pb 1×10-6,Zn 3×10-6,Cu 0.5×10-6,Bi 0.1×10-6,Ni 0.3×10-6,Co 0.3×10-6,Cr 1×10-6,基本上达到了化探普查找矿定量分析的要求.  相似文献   

12.
为了快速、准确地检测土壤中多种重金属元素,建立一种王水消解同时测定土壤中Cu,Zn,Ni,Cr,Pb,Cd的方法.选取8种具有广泛代表性的土壤标准物质对王水消解法进行考察,结合土壤标准物质标准值,通过大量试验数据对该方法做出全面评价.  相似文献   

13.
Free-drainage or “open” substrate system used for vegetable production in greenhouses is associated with appreciable NO3 leaching losses and drainage volumes. Simulation models of crop N uptake, N leaching, water use and drainage of crops in these systems will be useful for crop and water resource management, and environmental assessment. This work (i) modified the TOMGRO model to simulate N uptake for tomato grown in greenhouses in SE Spain, (ii) modified the PrHo model to simulate transpiration of tomato grown in substrate and (iii) developed an aggregated model combining TOMGRO and PrHo to calculate N uptake concentrations and drainage NO3 concentration. The component models simulate NO3-N leached by subtracting simulated N uptake from measured applied N, and drainage by subtracting simulated transpiration from measured irrigation. Three tomato crops grown sequentially in free-draining rock wool in a plastic greenhouse were used for calibration and validation. Measured daily transpiration was determined by the water balance method from daily measurements of irrigation and drainage. Measured N uptake was determined by N balance, using data of volumes and of concentrations of NO3 and NH4+ in applied nutrient solution and drainage. Accuracy of the two modified component models and aggregated model was assessed by comparing simulated to measured values using linear regression analysis, comparison of slope and intercept values of regression equations, and root mean squared error (RMSE) values. For the three crops, the modified TOMGRO provided accurate simulations of cumulative crop N uptake, (RMSE = 6.4, 1.9 and 2.6% of total N uptake) and NO3-N leached (RMSE = 11.0, 10.3, and 6.1% of total NO3-N leached). The modified PrHo provided accurate simulation of cumulative transpiration (RMSE = 4.3, 1.7 and 2.4% of total transpiration) and cumulative drainage (RMSE = 13.8, 6.9, 7.4% of total drainage). For the four cumulative parameters, slopes and intercepts of the linear regressions were mostly not statistically significant (P < 0.05) from one and zero, respectively, and coefficient of determination (r2) values were 0.96-0.98. Simulated values of total drainage volumes for the three crops were +21, +1 and −13% of measured total drainage volumes. The aggregated TOMGRO-PrHo model generally provided accurate simulation of crop N uptake concentration after 30-40 days of transplanting, with an average RMSE of approximately 2 mmol L−1. Simulated values of average NO3 concentration in drainage, obtained with the aggregated model, were −7, +18 and +31% of measured values.  相似文献   

14.
冀、鲁、豫、苏、皖五省农机夏收跨区作业调研报告   总被引:1,自引:0,他引:1  
农机跨区作业是我国农民自发进行的又一项伟大的制度创新,为促进我国农业机械化发展做出了重要的贡献.为此,采用问卷调查法、文献资料法和数理统计法,对冀、鲁、豫、苏、皖等省505户参与跨区作业的农机大户进行了问卷调查.以问卷数据为基础,分析了农机大户的自身特征和经营状况,并总结了影响跨农机大户参与跨区作业的主要因素,最后提出了相应的对策建议.  相似文献   

15.
16.
The intensive irrigated rice-wheat systems in the northwest Indo-Gangetic Plains of South Asia are built on a long tradition of canal irrigation and the more recent advent of tubewells. Findings from farm surveys are used to examine water management and water productivity in the rice-wheat belt of India's Haryana State and Pakistan's Punjab province. Attributes of the irrigation sources help explain the widespread interest in groundwater use and the relative demise of canal water use. In each area groundwater now is the main irrigation source, used either solely or in conjunction with surface water. The ownership of tubewells is near universal among the surveyed farms, whereas conjunctive water use is more widespread during the monsoon season, among better endowed farmers and in the Pakistan Punjab. In Pakistan Punjab farmers primarily rely on diesel powered tubewells whereas Haryana farmers mainly use relatively cheaper electric power. Water productivity indicators for rice are markedly lower than those for wheat—largely reflecting significantly higher water inputs in paddy cultivation—but also vary between the study areas and by the prevailing water use, reflecting the limited incentives for farmers to use water wisely. A combination of technological, land use and market based approaches is likely to be most effective in achieving sustainable water management in these intensive cereal systems.  相似文献   

17.
The irrigation sector is facing a serious maintenance crisis.Hydraulic infrastructure in many irrigation schemes, especially in South Asia,much of it constructed in the 1960's and 1970's, is deteriorating rapidly. The usual reaction to the neglect of maintenance has been a pattern of ``build-neglect-rebuild' which, in the wake of widespread budgetary constraints, cannot be an option for the future.The paper starts with the observation of a ``maintenance paradox': while there is general agreement amongst irrigation experts, that deferred maintenance is one of the most important determinants of performance deficits in irrigation,there is a relative lack of attention to the maintenance problem by government officials, irrigation agency staff, farmers and international development agencies. Going beyond the common explanation of ``lack of funds' and the related singular focuson maintenance financing, the paper perceives the low interest in maintenance as a multi-facetted incentive problem effecting most of the actors involved in maintenance provision. When maintenance is defined as a component of infrastructure service provision,the doors open to new insights on motivation and coordination problems in maintenance provision. Drawing on key concepts of the MAINTAIN project, the authors use such insights to put forward essential institutional requirements and basic strategiesthat may lead the way to incentive creation for maintenance and thus help overcomethe maintenance paradox in the irrigation sector.  相似文献   

18.
内蒙古河套灌区GSPAC水分通量分析   总被引:10,自引:1,他引:10  
阐述了内蒙古河套灌区的水文要素特征和农业节水改造形势。综合考虑区域性水循环过程中地下水系统、地表水系统和土壤植物大气连续体的密切联系,建立了内蒙古河套灌区人工自然复合型的GSPAC系统模型。以各子系统的水均衡为控制条件,计算了现状和节水改造后灌区GSPAC水循环界面通量,并预测了地下水埋深变化的幅度。  相似文献   

19.
The symposium was convened to provide a forum for an international exchange of papers describing current agricultural ergonomic research and interests. These multidisciplinary meetings of medical, engineering, agricultural and other scientists ensure that those working in countries where close and specialised liaison does not yet exist can return home with fresh examples of the benefits. The medical participants are able to report on the clinical effects of farming systems while the engineering and ergonomist members can report on their efforts to improve systems—prevention of stress being better than cures for the symptoms of excessive stress: the ideal, stress-free farm system being so far only an illusionary concept.  相似文献   

20.
沙棘,亚欧种,1753年植物学家Karl von Linné发现了沙棘并分类为"植物志"的第1023种.沙棘(Hippophae rhamnoides)被认为是希腊语"闪闪发亮的马"的语源.罗马尼亚的专家论证了沙棘对动物健康的影响,特别是皮肤方面,沙棘还有着消除肠内病菌的作用.  相似文献   

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