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1.
为了改进和提高温室封闭式栽培精细灌溉控制方法,针对利用Penman-Monteith(P-M)公式和传感器数据信息相结合进行灌溉控制中因为涉及参数较多而使用不便、需要近似计算导致建立的作物蒸腾模型精度不够等问题,该文根据封闭式栽培可以回收并循环利用多余灌溉水的特点,利用灌溉量与排出量的差值和温室小气候环境数据建立相对精确的作物蒸腾量计算模型,并在此基础上利用人工神经网络算法实现了温室封闭式栽培自适应灌溉控制,结果表明,在10 d内灌溉用水量为实际蒸腾量的97.8%,基本实现了按照作物需水量进行灌溉。研究对于实现按照作物蒸腾量进行准确的水分供给、节约灌溉用水量、提高水分利用效率具有一定的现实意义。  相似文献   

2.
电子鼻与电子舌在食品检测中的应用研究进展   总被引:45,自引:7,他引:45  
随着嗅觉与味觉传感器技术的发展,电子鼻与电子舌技术在食品检测中得到了不断研究与应用。电子鼻由气敏传感器、信号处理和模式识别系统等功能器件组成。电子舌是用类脂膜作为味觉传感器,以类似人的味觉感受方式检测味觉物质。着重阐述了电子鼻与电子舌技术的结构组成,重点介绍了其在食品新鲜度检测、果蔬成熟度评价及饮料、酒类识别等轻工业中的应用现状与发展趋势,并指出了这些信息新技术实现过程中所需要解决的问题。  相似文献   

3.
Soil cultivation changes and usage of agricultural wastes can have profound impacts on greenhouse gas (GHG) emission from soil. In this study, the effects of soil cultivation and organic amendment on GHG emission were investigated using aerobic incubation. Surface soil (0–20 cm) from (1) rice–legume consecutive rotation (Rice) and (2) recently (<3 years) converted from rice field to plastic-covered intensive vegetable and flower production (VegC) were collected in Kunming, P.R. China. Rose (Rosa rugosa Thunb.) residues and cattle manure were applied at 5% by weight. Results indicated that N2O and CO2 fluxes were significantly influenced by soil cultivation, organic amendment, incubation time and their interaction (p <0.05). Applying cattle manure increased, while rose residue decreased, cumulative N2O emissions from soil (84 days). Rose residue application significantly increased cumulative CO2 emissions with peak values of 6371 (Rice) and 7481 mg kg?1 (VegC), followed by cattle manure addition figure of 2265 (VegC) and 3581 mg kg?1 (Rice). Both were significantly higher (p <0.05) than the un-amended Control at 709 (VegC) and 904 mg kg?1 (Rice). Our study demonstrates that a low C/N ratio in cattle manure is better than a high C/N ratio in rose residue in regard to reducing the global warming potential of agricultural soil.  相似文献   

4.
响应面设计法在温室番茄栽培中的应用   总被引:3,自引:2,他引:1  
为优化温室番茄的栽培条件,试验研究了不同栽培密度、施氮量和施钾量对日光温室番茄产量的影响。通过中心复合试验设计,构建三因素(栽培密度,氮肥,钾肥)五水平的响应面设计方法并建立番茄产量与三因子的二次回归数学模型。结果表明:三因素对温室番茄产量均有显著的影响(p0.01),影响的大小顺序为栽培密度施钾量施氮量;栽培密度与施氮量、施钾量之间存在显著的交互作用(p0.01),施氮量与施钾量之间的相互作用对番茄产量影响不显著(p0.05);多元二次回归分析结果显示,栽培密度、施氮量、施钾量与番茄产量之间的回归模型高度显著(p0.01)。统计分析确定温室番茄的最佳栽培条件为:栽培密度4.83万株/hm2,施氮量262 kg/hm2,施钾量513kg/hm2;在此条件下,温室番茄产量的预测值为119381kg/hm2,验证试验所得产量为121005kg/hm2。本研究为日光温室番茄高产、稳产和优质提供了理论依据。  相似文献   

5.
Abstract. Sisal production in Tanzania has declined sharply in the past two decades because of a decrease in the area grown and a decrease in yields. As sisal is cultivated without manuring, depletion of soil fertility is considered one of the main causes of the declining yields. This paper presents a balance of the macronutrients N, P, K, Ca and Mg for sisal grown in a plantation in NE Tanzania on deep, red clay soils (Ferralsols). Annual fibre yields declined from 2.5 t/ha in the 1960s to about 1 t/ha in the 1980s. Hybrid sisal is a demanding crop and in ten years, with a total fibre yield of 11 t/ha, about 260 kg of N, 40 kg of P, 385 kg of K, 890 kg of Ca and 330 kg of Mg are removed in the harvested leaves. A comparison of soils after two and three 10-yr cycles of sisal production showed that in the third cycle the pH decreased by 0.5 units and that exchangeable bases were decreased by fifty per cent or more. The amounts of K, Ca and Mg removed from the soil were similar to those in leaves. However, soil analyses could not detect changes in total N and available P, possibly because of the large amount of total N in the soil and the lack of precision in the N and P analyses. In the Ferralsols, potassium is likely to become deficient first, followed by magnesium and calcium. The soil has little available P, and an increase in soil acidity may decrease it further and also create aluminium and manganese toxicities. In order to maintain sisal production, fertilization with P, K, Ca and Mg is necessary, and to improve yields N must also be applied.  相似文献   

6.
集约化大棚蔬菜种植条件下土壤硒有效性的影响因子分析   总被引:2,自引:0,他引:2  
Soil properties dramatically change after long-term greenhouse vegetable cultivation, which further affects soil selenium (Se) nutritional status and plant Se uptake. An evaluation of Se availability after long-term greenhouse vegetable cultivation (GVC) can help in better understanding its influential factors under GVC conditions and will also facilitate further regulation of soil Se nutrition in GVC systems. Two typical GVC bases were chosen: one with clayey and acidic soil in Nanjing, southern China, and the other with sandy alkaline soil in Shouguang, northern China. Twenty-seven surface soil samples at the Nanjing base and 61 surface soil samples at the Shouguang base were collected according to cultivation duration and cultivation intensity. Soil properties including soil available Se (PO43--Se) and total Se (T-Se) were analyzed. The results showed that soil PO43--Se was significantly and negatively correlated with soil Olsen-P, available K (A-K), and electrical conductivity (EC) at the Nanjing base. At the Shouguang base, however, no significant correlation was found between soil PO43--Se and Olsen-P and EC, and soil PO43--Se increased with increasing soil organic matter (OM). Intensively utilized greenhouse vegetable cultivation caused significant changes in soil properties and further affected soil Se availability. Due to different management practices, the dominant factors affecting Se availability varied between the two GVC bases. At the Nanjing base, the dominant influential factor on soil Se availability was soil nutritional status, especially Olsen-P and A-K status. At the Shouguang base, where organic fertilizers were applied at high rates, soil OM was the dominant influential factor.  相似文献   

7.
设施蔬菜栽培对土壤阳离子交换性能的影响   总被引:10,自引:0,他引:10  
以辽宁省沈阳市于洪地区设施菜地及其相邻旱田土壤为研究对象,测定土壤的有机质、阳离子交换量、交换性盐基离子组成和土壤盐基离子饱和度,分析设施蔬菜栽培对土壤阳离子交换量及交换性盐基离子组成的影响。结果表明:(1)与旱田土壤相比,设施土壤有机质含量明显增加,上下层土壤有机质平均含量分别为35.6 g kg-1和18.0 g kg-1,分别是旱田上下层土壤有机质含量的2.1倍和1.8倍;设施土壤阳离子交换量呈上升的趋势,土壤阳离子交换量与有机质含量呈极显著正相关关系(r=0.603**,n=50,r0.01=0.361)。(2)与旱田土壤相比,不同层次设施土壤交换性盐基总量均有所增加,交换性盐基离子中除交换性Ca2+含量变化不大之外,交换性K+、Mg2+、Na+含量均显著增加;不同层次设施土壤交换性K+、Mg2+、Na+饱和度显著高于旱田土壤,但交换性Ca2+饱和度和盐基饱和度呈下降趋势。  相似文献   

8.
日光温室甜椒有机土壤栽培试验研究   总被引:1,自引:1,他引:1  
利用麦秸与玉米秸、菇渣、草坪草等农产废弃物与土壤有机肥混合配制有机土壤进行了日光温室甜椒栽培越冬生产。结果表明,不同有机化土壤处理均有促进甜椒生长,提高甜椒座果数而增产的效应,有机土壤栽培还可明显提早甜椒成熟期及提高甜椒产量。  相似文献   

9.
日光温室番茄长季节生产专家系统的研制   总被引:7,自引:3,他引:7  
为了实现对温室番茄长季节生产的定量管理,对生产提供决策指导,根据温室番茄长季节栽培技术规范研制了温室番茄长季节生产专家系统。依靠对有效积温的计算,结合设施环境条件和番茄的生长发育期拟合番茄的生长阶段、成熟期及病虫害的发生规律与环境温湿度、有效积温之间的关系,为温室番茄生产向定量化、智能化管理创造了条件。通过将专家研究资料与计算机技术相结合,为温室番茄长季节高产高效栽培技术的推广提供途径。  相似文献   

10.
日光温室土壤剖面矿质态氮的含量、累积及其分布特性   总被引:11,自引:0,他引:11  
测定了西安郊区和杨凌地区日光温室栽培番茄生长期间及收获后土壤剖面矿质态氮(铵态氮及硝态氮)的含量,分析了不同形态氮素在土壤剖面的累积及分布情况。结果表明,随着番茄的生长,土壤剖面硝态氮含量逐渐降低,降低的幅度因土壤层次不同而异;土壤剖面铵态氮以3月份含量最高,11月份与5月份相近。番茄收获后土壤剖面残留矿质氮以硝态氮为主,约占土壤剖面矿质氮的比例为80%~90%;残留的铵态氮在土壤剖面的分布相对较为一致。蔬菜生长期间及收获时日光温室土壤剖面硝态氮累积量均表现出在土壤表层相对累积现象,且温室土壤剖面硝态氮的残留量仍高于露地及高产农田。为减少硝态氮淋失带来的环境问题,除合理施用氮肥外,如何减少日光温室蔬菜作物收获后残留硝态氮的淋溶是值得进一步研究的问题。  相似文献   

11.
Nutrient‐rich biochar produced from animal wastes, such as poultry litter, may increase plant growth and nutrient uptake although the role of direct and indirect mechanisms, such as stimulation of the activity of mycorrhizal fungi and plant infection, remains unclear. The effects of poultry litter biochar in combination with fertilizer on mycorrhizal infection, soil nutrient availability and corn (Zea mays L.) growth were investigated by growing corn in a loam soil in a greenhouse with biochar (0, 5 and 10 Mg/ha) and nitrogen (N) and phosphorus (P) fertilizer (0, half and full rates). Biochar did not affect microbial biomass C or N, mycorrhizal infection, or alkaline phosphomonoesterase activities, but acid phosphomonoesterase activities, water‐soluble P, Mehlich‐3 Mg, plant height, aboveground and root biomass, and root diameter were greater with 10 Mg/ha than with no biochar. Root length, volume, root tips and surface area were greatest in the fully fertilized soil receiving 10 Mg/ha biochar compared to all other treatments. The 10 Mg/ha biochar application may have improved plant access to soil nutrients by promoting plant growth and root structural features, rather than by enhancing mycorrhizal infection rates.  相似文献   

12.
利用麦秸与玉米秸、菇渣、草坪草等农产废弃物与土壤有机肥混合配制有机土壤进行了日光温室甜椒栽培越冬生产。结果表明,不同有机化土壤处理均有促进甜椒生长,提高甜椒座果数而增产的效应,有机土壤栽培还可明显提早甜椒成熟期及提高甜椒产量。  相似文献   

13.
Two studies were conducted to find the effects of zeolite in soilless cucumber culture. Zeolite was enriched by essential cations (Zcat) for some treatments and with essential cations plus iron sulfate (Zfe) in others. In 2010, various ZFe levels were compared with various amounts of iron in irrigation water and various zeolite levels in two enrichment methods were studied. In 2011, various ZFe levels mixed with Peatlite and also perlite were compared with various amounts of iron in irrigation water. The effects of treatments on iron concentration of leaves were not significant, which could be because iron was supplied by releasing it from zeolite. Using ZFe as iron resource increased the yield and vigor of plants in proportion to iron chelates. Enrichment methods did not have significant effect on measured traits. ZFe had provided iron requirement of plant. Perlite in comparison to Peatlite did not affect iron absorption.  相似文献   

14.
The decomposition of beech (Fagus sylvatiea L.) leaf litter was examined in lysimeters. The experiment allowed comparison of data from mass changes of bioelements in leaf litter and the solution flux balance of through fall input and lysimeter output over a two-year period (1983 and 1984). The annual C loss from the leaf litter was 19%. Na and K concentrations in this leaf litter decreased in the first year and remained constant in the second, while those of Ca and Mg showed no significant changes. N and S amounts per ha increased during the first year by about 7 kg N ha?1 and 0.5 kg S ha?1. Ash, Fe, Mn and Al amounts per ha increased to 470, 130 and 240% of their initial levels. These net increases in the first year of decomposition are discussed. The mean annual water and element input by through fall during the experiment corresponded approximately to the long-term average. Thirty to 40 mm more water was evaporated from the litter layer in the drier year (1983) than in 1984. Total N, NO, Na and C1 flux rates of through fall inputs and lysimeter outputs were equal. NH, input rates were greater and organic N smaller than the output rates of the lysimeters. Water balance data indicated that the lysimeter output of K, Mg, Ca and SO, exceeded through fall input. Probable reasons for these differences are discussed.  相似文献   

15.
为了降低现有设施环境监测系统中传感节点的能耗,延长无线传感网络的生存周期,该文提出了节点动态组包主动传输和多种环境变量加权控制传输2种低功耗机制,减少了大量重复冗余数据的传输,并实现了基于Zigbee的设施花卉环境监测及其低功耗传输系统。节点以CC2430芯片为核心,并根据影响花卉生长的环境参数,同时装载SHT10温湿度传感器、BH1750FVI光照传感器以及COZIR二氧化碳传感器,因此节点可同时采集传输多种环境参数,降低了硬件成本。在南农大园艺试验基地进行组网测试,试验结果表明,系统比传统周期传输节点(周期1min)的能耗减少85.97%,测量精度在98.5%以上,网络平均丢包率为0.84%,满足了对设施花卉环境的有效监测及低功耗传输的要求。  相似文献   

16.
设施栽培番茄的氮磷钾肥料效应研究   总被引:6,自引:2,他引:6       下载免费PDF全文
采用"3414"肥料试验设计开展了设施栽培番茄的氮、磷、钾肥料效应研究。结果表明,在高肥力土壤上适量施用氮、磷、钾肥均可增加番茄产量,但过量施用会降低其产量;钾肥的增产作用大于磷肥,氮肥的作用较小;氮、钾肥和磷、钾肥配施可增加番茄产量,而氮、磷肥配施降低产量。氮、磷(P_2O_5)和钾(K_2O)最佳经济施肥量分别为119.0、50.4和375.6 kg/hm~2,施肥比例为1∶0.42∶3.16。不同施氮量对番茄硝酸盐和亚硝酸盐含量的影响不规律,增施磷、钾肥番茄硝酸盐含量呈先增加后减少趋势;氮、磷肥和磷、钾肥配施可降低番茄硝酸盐和亚硝酸盐含量。氮、钾肥和磷、钾肥配施提高了番茄可溶性糖含量,氮、磷肥和磷、钾肥配施降低了番茄总酸含量,氮、钾肥配施则有增加番茄总酸含量的趋势,氮、钾肥和磷、钾肥配施均可提高番茄Vc含量。氮、磷、钾肥料合理配施对番茄产量和品质的提高具有重要作用。  相似文献   

17.
The aim of this trial was to study the spatio-temporal variability in solution nutrient concentration under intensive greenhouse tomato production, to determine the number of suction-cups needed to obtain a representative sample and the influence by the position in the greenhouses. Twenty sampling points were selected within the greenhouse with one suction-cup per sampling point. One soil solution were sampled per point at weekly intervals to analyze for pH, electrical conductivity, chloride, nitrate, phosphate, sulfate, sodium, potassium, calcium, and magnesium (EC, Cl?, NO3?, H2PO4?, SO42—, Na+, K+, Ca2+, and Mg2+) concentrations. The pH, Cl?, H2PO4?, and SO42? concentrations showed no spatio-temporal variation but EC, NO3?, and K+ showed temporal variation. The spatial variability in EC, K+, Na+, Mg2+, and Ca2+ can be influenced by microclimate and topography. The numbers of suction cups required for a representative sample ranged from 1 to 10 depending on nutrient.  相似文献   

18.
装配式日光温室砌筑不同蓄热墙体的增温和草莓栽培效果   总被引:3,自引:1,他引:2  
针对西北沙漠地区日光温室冬季夜间室内低温的问题,以新疆和田使用的装配式日光温室为研究对象,通过在温室内北侧砌筑砖墙体、砌块墙体和砌块填充沙土墙体3种材质的蓄热墙体,采用PT100铂电阻温度传感器对试验温室墙体、室内温度进行测试,并进行草莓栽培试验,用ACS-30型天平、LH-B55型数显折光仪进行草莓质量、可溶性固形物含量测量。由试验数据得,3种蓄热墙体体积、尺寸相同条件下,蓄热性能依次是:砌块填充沙土墙体砌块墙体砖墙体。装配式日光温室内砌筑砖墙体、砌块墙体和砌块填充沙土墙体,使得室温较装配式日光温室早晨07:00分别增加2.2、2.9和3.8℃。采用同样的种植管理技术,栽培的草莓开花期分别比原装配式日光温室早7、11和14 d,成熟期早14、17和20 d,单棚产量依次高24.2%、30.1%和33.4%,比装配式温室的草莓可溶性固形物质量分数平均值高1.4、2.1和2.6个百分点。进一步验证了墙体对日光温室热贡献的重要性,且砂浆砌块墙体比砖墙体增温效果明显,该墙体温室更适宜草莓生长。新砌筑墙体蓄热量与装配式温室热负荷计算数值一致,表明在没有其他加温设施的情况下,温室内新砌的墙体是室内夜间热源,可使温室内温度增加。该文为西北沙漠区日光温室墙体蓄热材料和结构设计提供参考,为日光温室内砂浆砌块的应用研究提供了依据。  相似文献   

19.
20.
孙艳  王益权  刘军 《土壤学报》2011,48(1):168-174
土壤的团聚状况是土壤重要的物理性质之一,团聚体的数量是衡量和评价土壤肥力的重要指标。用干筛法、湿筛法及带水振荡法对日光温室土壤和露地土壤的团聚体含量进行了测定,并进行了比较。根据干筛法测得的各级团聚体含量及平均重量直径(MWD)的评判,日光温室土壤大于10 mm团聚体的机械稳定性低于露地土壤。根据大于0.25 mm水稳性团聚体含量、水稳性团聚体的MWD值、团聚体的破坏率及团聚体的原始稳定系数和崩解速率等指标评判,日光温室土壤团聚体的水稳性高于露地土壤。日光温室蔬菜栽培年限长于5 a后,土壤中团聚体的机械稳定性显著降低,水稳性显著提高。  相似文献   

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