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1.
卢皖 《气象》1993,19(1):46-48
根据1988—1989年人工覆盖和裸地栽培西瓜的小气候试验资料,分析了人工覆盖栽培西瓜丰产早熟的小气候效应,并提出了与人工覆盖栽培西瓜有关的几个农业气象指标。  相似文献   

2.
本文分析了气象条件对西瓜生产影响,提出了早熟栽培西瓜的措施,并通过试验研究了早熟栽培的气象效应,认为早熟栽培可以充分利用气候资源,获得较高的收益。  相似文献   

3.
对大棚栽培和露天生产香椿的质量及产量进行了比较,认为在大棚栽培中,应合理进行棚内温度、湿度及光照的调节,并采取打顶促分枝、套隔光薄膜袋等技术,以提高产量和质量,使大棚栽培香椿一年四季可采,全年均衡供应。  相似文献   

4.
东台西瓜大棚内外温度关系及高低温预警方法研究   总被引:3,自引:0,他引:3  
根据东台大棚西瓜生产普遍模式和研究目的,建立相应的试验观测站,分别选择夜间低温样本和白天晴天条件样本,对资料序列进行分析。结果表明:夜间塑料大棚内温度与外界温度密切相关;白天晴天条件下大棚内温度与外界温度、太阳高度角、太阳光通过大气对流层的斜距等因子有着显著的相关关系。运用统计回归方法建立夜间低温条件下和白天晴天条件下大棚内外温度关系,达到较高的准确率和精度;结合冻害温度指标和发生冻害的可能性大小,确定夜间低温预警指标等级及温度范围,并对白天晴天条件下大棚内指标温度出现时间进行尝试性预测,有针对性地服务于大棚西瓜的生产过程。  相似文献   

5.
1前言东北南部被称为燕辽易早地区的有代表性的县份——辽宁省喀左县,在生产兼育苗的日光温室(钢筋水泥结构或竹木结构)的日光温室中搞蔬菜育苗只有七八年的历史,当地农民在保护地育苗和栽培方面的经验不够丰富.近年来,广大菜农,包括从事保护地日光温室栽培和育苗的大棚专业户,通过参考科学普及书刊,  相似文献   

6.
早春温室果菜类生态型无土栽培技术试验   总被引:2,自引:0,他引:2  
在玻璃温室中 ,利用当地充足的木屑、河沙等原料 ,再添加一定比例的畜禽干粪 ,经高温酸酵处理的有机生态基质 ,进行果菜类无土立体化栽培试验 ,得出果菜产量较传统无土栽培及营养土培分别增产 2 1%~ 4 6 %和 6 6 %~ 10 2 % ,上市期提前 11~ 2 6d和 2 4~ 37d。为当地无土栽培的大面积推广和温室 (大棚 )立体化栽培的合理布局提供了科学依据 ,在实际生产应用中有广阔的推广前景  相似文献   

7.
第五讲甘肃名优特产气候资源与利用余优森1名优瓜果名优瓜果产品的品质与土壤、气候、品种、栽培等因子有关,而当地得天独厚的气候资源优势则是主要因素。甘肃的名优瓜果和土特产品皆与待定的气候生态条件及其优质气候层带有直接联系。1.1甜瓜和西瓜白兰瓜是甘肃省主...  相似文献   

8.
通过对日光温室大棚实用技术的初探 ,寻找大棚栽培油桃的气象指标 ,为发展种植业提供农业气象科学依据  相似文献   

9.
塑料大棚种植技术,是我国北方冬春季节进行保护栽培的主要方式,也是一项高投入高产出的种植技术。为了更好地利用大棚内的有限空间,产出更多的果菜,本文提出几种有利于大棚高产栽培的技术方法:1提高大棚的光能利用率首先,设计和建造大棚要考虑到光照、温度、生产管...  相似文献   

10.
通过对日光温室大棚实用技术的初探,寻找大棚栽培油桃的气象指标,为发展种植业提供农业气象科学依据。  相似文献   

11.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.  相似文献   

12.
The atmospheric and oceanic conditions before the onset of EP El Ni?o and CP El Ni?o in nearly 30 years are compared and analyzed by using 850 hPa wind, 20℃ isotherm depth, sea surface temperature and the Wheeler and Hendon index. The results are as follows: In the western equatorial Pacific, the occurrence of the anomalously strong westerly winds of the EP El Ni?o is earlier than that of the CP El Ni?o. Its intensity is far stronger than that of the CP El Ni?o. Two months before the El Ni?o, the anomaly westerly winds of the EP El Ni?o have extended to the eastern Pacific region, while the westerly wind anomaly of the CP El Ni?o can only extend to the west of the dateline three months before the El Ni?o and later stay there. Unlike the EP El Ni?o, the CP El Ni?o is always associated with easterly wind anomaly in the eastern equatorial Pacific before its onset. The thermocline depth anomaly of the EP El Ni?o can significantly move eastward and deepen. In addition, we also find that the evolution of thermocline is ahead of the development of the sea surface temperature for the EP El Ni?o. The strong MJO activity of the EP El Ni?o in the western and central Pacific is earlier than that of the CP El Ni?o. Measured by the standard deviation of the zonal wind square, the intensity of MJO activity of the EP El Ni?o is significantly greater than that of the CP El Ni?o before the onset of El Ni?o.  相似文献   

13.
Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration.  相似文献   

14.
Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter.  相似文献   

15.
A one-dimensional, time-dependent cloud model with parameterized microphysics is used to investigate the processes which control the rainout and washout of soluble gases from warm, precipitating stratiform clouds. Calculations are presented simulating the distributions of soluble species within and below the cloud layer and in the precipitating raindrops as a function of time and species' solubility. Our calculations indicate that for species with low solubility, wet removal processes are relatively slow and thus do not significantly affect the species' gas-phase abundance. As a result, the removal of low-solubility species by rainout and washout is controlled by thermodynamic processes with the concentration of the species in cloud and rainwater largely determined by the species' solubility. For highly soluble species on the other hand, dissolution into cloud droplets and removal in rain is quite rapid and the abundance of highly soluble species within and below the cloud falls rapidly as soon as the precipitation begins. Because of this rapid decrease in concentration, we find that for highly soluble species: concentrations in cloud droplets near the cloud base can exceed that of raindrops by factors of 2 to 10; washout can dominate over rainout as a removal mechanism; and that, after an extended period of rainfall, the rate of removal becomes independent of the microphysical properties and rainfall rate of the cloud and is controlled by the rate of transport of material into the precipitating column by horizontal advection.  相似文献   

16.
Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d.  相似文献   

17.
A review of recent advances in research on Asian monsoon in China   总被引:6,自引:0,他引:6  
This paper reviews briefly advances in recent research on monsoon by Chinese scholars, including primarily: (1) the establishment of various monsoon indices. In particular, the standardized dynamic seasonal variability index of the monsoon can delimit the geographical distribution of global monsoon systems and determine quantitatively the date of abrupt change in circulation. (2) The provision of three driving forces for the generation of monsoon. (3) The revelation of the heating-pump action of the Tibetan Plateau, which strengthens southerlies in the southern and southeastern periphery of the Plateau and results in a strong rainfall center from the northern Bay of Bengal (BOB) to the Plateau itself. (4) Clarification of the initial onset of the Asian Summer Monsoon (ASM) in the BOB east of 90°E, Indochina Peninsula (ICP) and the South China Sea, of which the rapid northward progression of tropical convection in the Sumatra and the rapid westward movement of the South Asia High to the Indochina Peninsula are the earliest signs. (5) The provision of an integrated mechanism for the onset of the East Asian Summer Monsoon (EASM), which emphasizes the integrated impact of sensible heat over Indian Peninsula, the warm advection of the Tibetan Plateau and the sensible heat and latent heat over the Indochina Peninsula on the one hand, and the seasonal phase-lock effect of the northward propagation of low frequency oscillation on the other. (6) The revelation of the "planetary-scale moisture transport large-value band" from the Southern Hemisphere through to the Asian monsoon region and into the North Pacific, which is converged by several large-scale moisture transport belts in the Asian-Australian monsoon regions and whose variation influences directly the temporal and spatial distribution of summer rainfall in China. (7) Presenting the features of the seasonal advance of the EASM, the propagation of intraseasonal oscillation, and their relationship with rainfall in Ch  相似文献   

18.
基于最新的GTAP8 (Global Trade Analysis Project)数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。  相似文献   

19.
冰冻圈变化的适应研究是冰冻圈科学领域的新兴研究方向,是当今自然科学与社会科学交叉融合跨学科集成研究的典型代表。起步于2007年的中国冰冻圈变化适应研究,经历了早期的探索,研究重点由评价脆弱性发展为量化冰冻圈变化的影响,形成以影响/风险—脆弱性—适应全链条的完善的研究体系,研究方法突破传统的指标体系赋权法的不足,初步实现了定量化,有机结合影响/风险、脆弱性、适应三方面的研究结果,使冰冻圈变化的适应措施由偏重宏观性、普适性开始转向更有针对性。未来中国冰冻圈变化的适应研究应拓展、完善和深化现有的理论体系,构建冰冻圈与社会经济耦合模型,科学量化冰冻圈全要素变化的影响,建立不同利益相关者与科学家共同参与的研究新模式,科学有效应对与适应冰冻圈变化及其影响。  相似文献   

20.
The predictability of the position, spatial coverage and intensity of the East Asian subtropical westerly jet(EASWJ) in the summers of 2010 to 2012 was examined for ensemble prediction systems(EPSs) from four representative TIGGE centers,including the ECMWF, the NCEP, the CMA, and the JMA. Results showed that each EPS predicted all EASWJ properties well, while the levels of skill of all EPSs declined as the lead time extended. Overall, improvements from the control to the ensemble mean forecasts for predicting the EASWJ were apparent. For the deterministic forecasts of all EPSs, the prediction of the average axis was better than the prediction of the spatial coverage and intensity of the EASWJ. ECMWF performed best, with a lead of approximately 0.5–1 day in predictability over the second-best EPS for all EASWJ properties throughout the forecast range. For probabilistic forecasts, differences in skills among the different EPSs were more evident in the earlier part of the forecast for the EASWJ axis and spatial coverage, while they departed obviously throughout the forecast range for the intensity. ECMWF led JMA by about 0.5–1 day for the EASWJ axis, and by about 1–2 days for the spatial coverage and intensity at almost all lead times. The largest lead of ECMWF over the relatively worse EPSs, such as NCEP and CMA, was approximately 3–4 days for all EASWJ properties. In summary, ECMWF showed the highest level of skill for predicting the EASWJ, followed by JMA.  相似文献   

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