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61.
设施农业的快速发展,推动了高寒地区种植业的多样化.葡萄产业由于品种繁多,产业链长,市场效益高,发展尤为突出,通过调查大同地区的几个县区葡萄大棚栽培模式分析构成质优高产的综合因素,总结出大棚栽培葡萄的优势. 相似文献
62.
温室环境信息智能化管理研究进展 总被引:10,自引:0,他引:10
随着我国温室园艺业和信息技术的迅速发展,现代信息技术越来越多地应用于温室环境管理中,促进了温室环境智能化管理技术的发展。本文针对面向物联网的温室环境信息智能化管理需求,分别从温室环境信息获取、信息处理与决策服务3个方面对国内外研究进展进行了系统的分析和阐述,并提出了今后在温室环境信息智能化管理方面迫切需要开展的工作。 相似文献
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Georgia R. Koerber Paul W. Hill Gareth Edwards-Jones David L. Jones 《Soil biology & biochemistry》2010,42(10):1835-1841
Distinguishing between root and non-root derived CO2 efflux is important when determining rates of soil organic matter turnover, however, in practice they remain difficult to separate. Our aim was to evaluate two methods for determining the component of below-ground respiration not dependent on plant roots (i.e., basal soil respiration; Rb). The first approach estimated Rb indirectly from the y-intercept of linear regressions between below-ground respiration (BGR) and root biomass. The second approach involved direct measurements of soil respiration from bare plots. To compare the contrasting approaches, BGR and crop biomass measurements were collected throughout the year in a range of agricultural systems. We found that both methods were very closely correlated with each other. Values of Rb determined by the intercept approach, however, were slightly higher than those determined by measurement of bare plots. Both approaches showed a seasonal trend with estimates of Rb lowest in winter months at 0.02 t C ha−1 month−1 for the y-intercept approach and 0.11 t C ha−1 month−1 for the bare plots approach, even after the data had been corrected for the influence of soil temperature. Highest rates of Rb occurred from the height to the end of the crop growing season (0.8-1.5 t C ha−1 month−1). The annual CO2 efflux due to Rb was estimated to be 8.1 t C ha−1 y−1 from the y-intercept approach and 6.8 t C ha−1 y−1 from bare plots. Annual BGR was 12.1 t C ha−1 y−1. We conclude that both methods provide similar estimates of Rb, however, logistically the bare plots approach is much easier to undertake than the y-intercept approach. 相似文献
64.
Tjaša Danev?i? Bla? Stres David Stopar Janez Hacin 《Soil biology & biochemistry》2010,42(9):1437-1446
Peatlands play an important role in emissions of the greenhouse gases CO2, CH4 and N2O, which are produced during mineralization of the peat organic matter. To examine the influence of soil type (fen, bog soil) and environmental factors (temperature, groundwater level), emission of CO2, CH4 and N2O and soil temperature and groundwater level were measured weekly or biweekly in loco over a one-year period at four sites located in Ljubljana Marsh, Slovenia using the static chamber technique. The study involved two fen and two bog soils differing in organic carbon and nitrogen content, pH, bulk density, water holding capacity and groundwater level. The lowest CO2 fluxes occurred during the winter, fluxes of N2O were highest during summer and early spring (February, March) and fluxes of CH4 were highest during autumn. The temporal variation in CO2 fluxes could be explained by seasonal temperature variations, whereas CH4 and N2O fluxes could be correlated to groundwater level and soil carbon content. The experimental sites were net sources of measured greenhouse gases except for the drained bog site, which was a net sink of CH4. The mean fluxes of CO2 ranged between 139 mg m−2 h−1 in the undrained bog and 206 mg m−2 h−1 in the drained fen; mean fluxes of CH4 were between −0.04 mg m−2 h−1 in the drained bog and 0.05 mg m−2 h−1 in the drained fen; and mean fluxes of N2O were between 0.43 mg m−2 h−1 in the drained fen and 1.03 mg m−2 h−1 in the drained bog. These results indicate that the examined peatlands emit similar amounts of CO2 and CH4 to peatlands in Central and Northern Europe and significantly higher amounts of N2O. 相似文献
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2013-2014年在设施大棚条件下,以玉云苦瓜为对照,对新翠、翠玉、雅秀、春晓1号、翡玉5个苦瓜品种进行对比试验。试验结果表明,新翠苦瓜早熟、商品性优、生长势强,产量达5 394.3 kg/667 m2,综合性状优于其他5个品种,是平和地区早春设施大棚大面积种植的首选品种。 相似文献
69.
为对水肥一体化在生产上的应用提供数据支持,在河北永年县开展了棚室番茄水肥一体化技术与常规普通施肥对比试验。试验结果表明,采用每667 m2用水250 m3、追肥40 kg的水肥一体化技术,可比常规栽培节水34.2%、节肥20%,番茄增产4.74%。 相似文献
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