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41.
本文根据温室番茄长季节栽培技术经验,利用农业专家系统开发平台(单机版)PAID4.0,开发温室番茄长季节栽培管理专家系统。本系统包括番茄栽培管理、病虫害防治模块、248条规则。通过将专家研究成果与计算机的结合为温室番茄长季节高效栽培技术的推广提供了广阔的应用前景。 相似文献
42.
F. J. Vázquez V. Petrikova M. C. Villar T. Carballas 《Biology and Fertility of Soils》1996,22(3):265-271
Annual (Pisum sativum L. and Vicia sativa L.) and perennial (Trifolium repens L. and Lotus corniculatus L.) leguminous species were grown in pots containing samples from the ash layers of two Cambisols under Pinus sylvestris L., which has been affected by high-intensity wildfires 3 and 15 days before the sampling. The gramineous Lolium perenne L. was cultivated as a second plant after Trifolium and Lotus harvesting. Three treatments were compared: soils without fertilization and soils fertilized with two doses of poultry manure (1 and 2 g total N kg-1 dry soil). The aim of the work was to study the capacity of the ash layer to sustain vegetation and the influence of plants and organic manure on the recovery of vegetation cover, ash layer fixation and soil structure formation to avoid erosion. The ash samples were able to sustain vegetation without fertilization. The organic manure increased the yields of all the plants tested, the lower dose being the optimal for the first crop whereas the higher dose was beneficial for the second crop. The annual legumes grew very quickly. The mixture of Trifolium and Lotus seemed very suitable for reclamation of soil degraded by wildfires because Trifolium produced more phytomass than Lotus in the first growing stages whereas the development of Lotus was higher in the later growing stages. Ash layer conditions did not inhibit nodulation, which was, however, stimulated by the organic manure, particularly in the case of Lotus. Lolium after perennial legumes was the best plant combination because it produced the highest phytomass, particularly root phytomass, and thus improved vegetation cover and ash layer fixation. All the plants tested improved the formation of soil aggregates, particularly the combination of perennial legumes and Lolium. However, wet aggregate stability was higher when plants were grown on soils fertilized with poultry manure than when plants were cropped on unmanured soils, which points to the favourable influence of the organic manure on soil aggregation. 相似文献
43.
施肥与大气环境质量——论施肥对环境的影响(1) 总被引:21,自引:4,他引:21
无机肥和有机肥都是人类可持续发展不可或缺的资源,只要科学使用不会对环境和生态造成负面影响。不良施肥对大气环境的威胁主要来自有机肥,过量使用有机肥可促进土壤中CO2和CH4的排放;有机肥和畜禽粪肥堆放场地有大量氨气污染,有机物的焚烧可直接向大气排放大量的CO2、CH4及固体微粒,使城乡空气严重污染。有机肥和无机N肥的过量使用,都会导致土壤N素积累。土壤中N素的反硝化作用产生N2O, NOx 的排放。避免有机肥和N肥过量,禁止焚烧有机物,覆盖有机肥和畜禽粪肥堆放场,控制反硝化作用,以减少负面效应,保护大气环境质量。 相似文献
44.
自控温室气象条件对甜椒产量的影响 总被引:1,自引:0,他引:1
根据上海东海蔬菜示范基地1996~1997年2茬甜椒产量资料及同期温室内的气象资料,运用数理统计方法分析气象条件对甜椒产量的影响,初步得出温室中甜椒生长关键期的适宜气象指标为播种约30d日最低温度为1.5~15.0℃,日最高温度25.0~25.5℃,CO2浓度400~450mg/kg;播种后加热管温度50℃;而播种后10d左右相对湿度维持在75%,80d左右光照强度为6~6.5万lx。 相似文献
45.
自控温室番茄生产的光合数值模拟 总被引:1,自引:0,他引:1
使用CIRAS-1便携式光合仪测定了荷兰大型玻璃自控温室内番茄光合能力对环境条件的响应,由实测值和参考文献确定了有关参数,运用非直角双曲线叶面积积分模型模拟温室不同气象条件下番茄净光合量的增减,探讨了提高光合产量的调控措施。 相似文献
46.
47.
在日光温室内,采用田间试验的方法,研究不同施肥处理对西红柿土壤酶活性和土壤微生物数量的影响。结果表明:施有机肥、化肥、有机肥 叶面肥处理土壤磷酸酶活性增加,施化肥 叶面肥处理比施化肥处理土壤磷酸酶活性增加;施有机肥处理土壤脲酶活性增强;施化肥 叶面肥处理土壤磷酸酶活性比施有机肥 叶面肥处理降低;施肥对蔗糖酶和过氧化氢酶活性的影响较小。施有机肥处理土壤细菌、真菌和放线菌数量增加,施化肥处理土壤细菌数量降低,土壤真菌和放线菌数量增加。 相似文献
48.
温室盆栽试验研究土壤水分对黄瓜叶面积扩展与光合特性的影响结果表明,黄瓜叶片扩展经历了指数生长(EG)、线性生长(LSG)和稳定生长(SCG)3个阶段。随土壤含水量的增加,叶面积(LA)显著增大,叶片生长速率(LGR)的最大值明显提前。叶片相对扩展速率(RER)在指数生长阶段迅速增加,但在线性生长和稳定生长阶段则逐渐减小。土壤含水量显著影响了叶片的扩展和光合特性。叶片生长进程中,叶绿素含量和净光合速率(Pn)逐渐增加,处理间差异明显,不同水分处理的叶片净光合速率日变化均表现为单峰曲线,其表观量子效率(AQY)、羧化效率(CE)具有显著差异。 相似文献
49.
In a greenhouse study, methane emissions were measured from two diverse Indian rice-growing soils planted to five rice cultivars
under similar water regimes, fertilizer applications and environmental conditions. Significant variations were observed in
methane emitted from soils growing different cultivars. Total methane emission varied between 8.04 and 20.92gm–2 from IARI soil (Inceptisol) and between 1.47 and 10.91gm–2 from Raipur soil (Vertisol) planted to rice. In all the cultivars, emissions from IARI soil were higher than from Raipur
soil. The first methane flux peak was noticed during the reproductive phase and the second peak coincided with the grain-ripening
stage of the rice cultivars.
Received: July 7, 1996 相似文献
50.
Methane emission and entrapment in flooded rice soils as affected by soil properties 总被引:7,自引:0,他引:7
Z. P. Wang C. W. Lindau R. D. Delaune W. H. Patrick Jr. 《Biology and Fertility of Soils》1993,16(3):163-168
Laboratory incubation experiments were conducted to study the effects of soil chemical and physical properties on CH4 emission and entrapment in 16 selected soils with a pH range of 4.7–8.1, organic matter content of 0.72–2.38%, and soil texture from silt to clay. There was no significant correlation with CH4 emission for most of the important soil properties, including soil aerobic pH (measured before anaerobic incubation), total Kjeldahl N, cation exchange capacity, especially soil organic matter, and soil water-soluble C, which were considered to be critical controlling factors of CH4 emission. A lower CH4 emission was observed in some soils with a higher organic matter content. Differences in soil Fe and Mn contents and their chemical forms contributed to the this observation. A significant correlation between the CH4 emission and the soil organic C content was observed only after stratifying soils into subgroups according to the level of CH4 emission in soils not amended with organic matter. The results also showed that the soil redox potential (Eh), anaerobic pH, anerobic pH, and biologically reducible Fe and Mn affected CH4 emission significantly. Urea fertilization promoted CH4 emission in some soils and inhibited it in others. This result appeared to be related to the original soil pH. CH4 entrapment was positively correlated with soil clay content, indicating the importance of soil physical characteristics in reducing CH4 emissions to the atmosphere. 相似文献