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本文通过比较和统计的手段,在分析经济发展的客观要求与旅游业的社会、经济功能的基础上,论述了乌鲁木齐经济发展与旅游繁荣的结合点,尤其突出了振兴旅游对乌鲁木齐经济发展的重要促进作用. 相似文献
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南美白对虾卵巢结构及发育的组织学研究 总被引:7,自引:0,他引:7
本文采用组织学方法研究南美白对虾的卵巢结构及其发育。结果表明:卵巢由卵巢壁、中央卵管和卵室组成:卵巢壁由外向内分为上皮层、肌层、基膜和分化上皮四部分;中央卵管分化出大量卵原细胞;卵室内含有不同发育阶段的卵母细胞。卵巢发育具有明显的体积与色泽的变化,根据外部形态和内部结构,可将其分为增殖期、小生长期、大生长期早期、将成熟期、成熟期和恢复期六个时期。 相似文献
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选取开都河与乌鲁木齐河山区流域为研究区域,利用有关水文气象台站1960-2005年的观测资料,对研究区域的气温、降水与出山径流的变化特征及趋势进行了分析,并根据研究区域气候变化的特征与趋势及出山径流与山区降水、气温之间的关系,假定不同的气候情景组合,建立山区径流对气候变化的响应模型,以揭示天山南、北坡河流出山径流对气候变化的响应及其差异.结果表明,开都河与乌鲁木齐河山区径流与气温、降水量均呈正相关关系,受山区降水、气温持续增加和上升的影响,出山径流总体呈上升趋势,1990年代以后的升幅尤为显著;相对而言,乌鲁木齐河山区径流对降水变化更为敏感,而开都河出山径流对气温变化的敏感性略甚于气温. 相似文献
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The distribution characteristics of the oil-water contact are the basis for the reservoir exploration and development and reserves evaluation. The reservoir with a tilted oil-water contact has a unique formation mechanism, and the understanding of its distribution and formation mechanism will directly affect the evaluations for the reservoir type, well deployment, selection of well pattern and type, determination of test section, and reserves evaluation. Based on the analysis of reservoir characteristics, petrophysical properties and geological structure in 40 reservoirs worldwide with tilted oil-water contacts, the progress of the research on the formation mechanisms of titled oil-water contacts is summarized in terms of the hydrodynamic conditions, reservoir heterogeneity, neotectonic movement and oil-gas exploitation. According to the formation mechanism of tilted oil-water contacts and the needs of exploration research, different aspects of research methods are summarized and classified, such as the calculation of equipotential surfaces for oil and water in the formation, analysis of formation pressure and analysis of reservoir physical properties and so on. Based upon statistical analysis, it is suggested that the degree of the inclination of the oil-water contact be divided based on the dip of oil-water contact(DipTOWC). The tilted oil-water contact is divided into three categories: large dip(DipTOWC≥55 m/km), medium dip(4 m/km≤DipTOWC55 m/km), and small dip(DipTOWC4 m/km). The classification and evaluation method can be combined with structure amplitude and reservoir property. The formation mechanism of domestic and international reservoirs with tilted oil-water contacts are summarized in this paper, which have important significance in guiding the exploration and development of the oilfield with tilted oil-water contacts, reserves evaluation, and well deployment. 相似文献
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Photosynthetic characteristics of spring ephemerals in the desert ecosystem of Dzungaria Basin,northwest China 总被引:1,自引:1,他引:0
Spring ephemerals have the highest photosynthetic rates in higher plants. Gas exchanges and related environmental factors
of four typical spring ephemerals, Eremopyrum orientale, Malcolmia scorpioides, Tetracme quadricormis and Arnebia decumbens were measured in their natural environments in the Gurbantunggut Desert of the Dzungaria Basin, northwestern China. Diurnal
variations in net photosynthetic rate (P
N), transpiration rate (E), stomatal conductance (gs), and water use efficiency (WUE) were analyzed at individual leaf level for these species. P
N of E. orientale and M. scorpioides showed a bimodal diurnal pattern, whereas that of T. quadricormis and A. decumbens showed a unimodal pattern, with the maximum value occurred at noon (around 12:00). E of all four species showed a unimodal pattern. Higher WUE in the morning was related to higher P
N and lower E. The maximum value of gs appeared in early morning, and then decreased gradually during the daytime. The highest photosynthetically
active radiation (PAR) occurred at 14:00, but there was a 2 h lag between the highest temperatures of air and leaf and the
highest PAR. The maximum net photosynthetic rate (P
Nmax) of the four spring ephemerals were 18.44, 32.03, 33.17, and 20.04 μmolCO2 m−2 s−1, respectively. The present study revealed that the midday depression of photosynthesis of E. orientale and M. scorpioides was mainly due to non-stomatal limitation, whereas that of T. quadricormis and A. decumbens was mainly due to stomatal limitation during 14:00–16:00 followed by non-stomatal limitation after 16:00. Our results illustrated
that the change of E was consistent with the diurnal fluctuation of air temperature, but the diurnal change of P
N was affected by the whole microclimate, i.e. temperature, relative humidity (RH), PAR, etc. 相似文献
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植物生长调节剂对绿色巴夫藻生长的影响 总被引:7,自引:0,他引:7
研究了二种植物生长调节剂对绿色巴夫藻 ( Pavlova viridis)的生长、叶绿素含量和干重的影响。结果表明 ,在试验浓度范围内 ,2 ,4— D对绿色巴夫藻生长的影响在培养早期比后期明显 ,最适浓度为 0 .1 m g/L ;6-BA质量浓度≥ 1 mg/L时对绿色巴夫藻有致死作用 ,质量浓度为 0 .1~ 0 .8mg/L时 ,对绿色巴夫藻的生长有促进作用 ,促进生长的最适质量浓度为 0 .5mg/L。在一定浓度范围内 ,二种植物生长调节剂都可促进绿色巴夫藻的生长 ,提高叶绿素含量 ,增加试验藻的干重。 相似文献
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