Analysis of Spatio-temporal Land Surface Temperature and Normalized Difference Vegetation Index Changes in the Andassa Watershed,Blue Nile Basin,Ethiopia

Analysis of the nexus between vegetation dynamics and climatic parameters like surface temperature is essential in environmental and ecological studies and for monitoring of the natural resources. This study explored the spatio-temporal distribution of land surface temperature (LST) and Normalized Difference Vegetation Index (NDVI) and the relationship between them in the Andassa watershed from 1986 to 2016 periods using Landsat data. Monthly average air temperature data of three meteorological sites were used for validating the results. The findings of the study showed that the LST of the Andassa watershed has increased during the study periods. Overall, average LST has been rising with an increasing rate of 0.081°C per year. Other results of this study also showed that there has been a dynamic change in vegetation cover of the watershed in all seasons. There was also a negative correlation between LST and NDVI in all the studied years. From this study we can understand that there has been degradation of vegetation and intensification of LST from 1986 to 2016.     

我国南方西南和中东部区域两次持续性低温雨雪过程与关键环流系统的关系研究

利用NCEP再分析资料和国家气象信息中心提供的753站逐日气温和降水资料,对比分析了我国南方西南和中东部区域两次持续10 d以上的低温雨雪过程,结果表明:(1)两次过程中欧亚大陆中高纬东亚大槽均加深,但环流形势有差异。西南过程呈现"北高南低"形势,关键脊区在贝加尔湖,而中东部区域过程"北高南低"和"西高东低"形势共存,关键脊区从乌拉尔山延伸至贝加尔湖。两次过程异常的环流与北大西洋向东传播的波列有关。(2)西南过程关键脊区提前过程3 d发展并东移至贝加尔湖,形成稳定形势;而中东部区域过程关键脊区提前过程一周发展,在开始日达最强。两次过程均伴随蒙古高压东移南压使地面降温,500 hPa关键脊区超前蒙古高压2 d变化。西南过程降温主要受到冷平流和绝热冷却影响,而中东部区域过程主要受到冷平流的影响。(3)西南过程水汽来自孟加拉湾,只受南支槽支配。中东部区域过程水汽来自孟加拉湾、南海和西太平洋,由南支槽和西太平副热带高压的共同影响。两次过程水汽正收支主要来自南边界。     

船载海水温度观测研究

通过研究国家相关海洋观测标准对海水温度观测的规约,结合当前船载水温观测的现状,提出了基于总线的船载磁吸附温度链式观测方法,并对其在结构设计、理论模型、算法等多方面进行了阐述.通过多个竖直分布的温度传感器实时观测,采用自适应参数化算法,有效减少了风浪、海流、热辐射等方面的影响,具有观测层深相对固定、精度高等特点,可实现船...     

近50年石家庄地-气温差变化特征

利用石家庄17个国家气象站1972—2021年逐日地面气温、0 cm地温资料,分析了石家庄地-气温差的变化特征,结果表明：(1)石家庄地-气温差从1月开始逐渐增加,5月达到最大值5.0℃,然后开始减小,12月达到最小值-0.8℃;地-气温差在11月到次年1月为负值;春、夏、秋季均为正值,夏季最大,春季大于秋季,冬季以负值为主;(2)石家庄多年平均地-气温差在1.6～2.6℃之间,平均为2.1℃;整体上东部大于西部。(3)近50年石家庄年平均地-气温差呈显著的减小趋势,变化速率为-0.14℃/10a;夏、秋、冬三季的减小趋势均非常显著,夏季的减小趋势最强;石家庄市区和近郊站点年和四季地-气温差的减少趋势更显著。本文结论对科学认识石家庄城市生态环境的变化具有参考意义。     

贵州省不同强度区域性凝冻过程环流形势对比分析

利用贵州省84个气象站逐日观测资料以及再分析资料,对4种不同强度区域性凝冻过程进行对比分析。结果表明：500 hPa位势高度场上中高纬度的亚洲东部区域距平场呈现“+-”的分布或有切断低压分布,贝加尔湖至中国华北地区以经向环流为主;850 hPa风场上云南南部以南受偏南风和西南风控制,并且在江南至华南存在西南或西风急流,是4种不同强度凝冻过程中形势场共性特征。500 hPa高度场上中高纬度地区呈两槽一脊或一槽一脊分布;风场上850 hPa东北风回流和700 hPa西南急流形成上暖下冷的形势场,同时850 hPa形成稳定低层切变线;温度场上存在冷-暖-冷的夹心结构,近地面层0 ℃线维持在900 hPa以下,均是较强等级以上的区域性凝冻过程中形势场共性特征。而对于一般性区域性凝冻过程,500 hPa位势高度场上呈多槽脊分布,风场上是否存在东北风回流和低层切变线,温度场上是否存在冷-暖-冷的夹心结构以及近地面层0 ℃线位置等特征均不统一。温度剖面图上,当近地面层0 ℃线位置最低时或出现冷-暖-冷的夹心结构时段与凝冻过程影响范围最广、灾情最重的时间段对应。     

Grey relational analysis on the relation between marine environmental factors and oxidation-reduction potential

The effects of marine environmental factors-temperature(T),dissolved oxygen(DO),salinity(S) and pH-on the oxidation-reduction potential(ORP) of natural seawater were studied in laboratory.The results show an indistinct relationship between these four factors and the ORP,but they did impact the ORP.Common mathematical methods were not applicable for describing the relationship.Therefore,a grey relational analysis(GRA) method was developed.The degrees of correlation were calculated according to GRA and the va...     

Detection of the end point temperature of thermal denatured protein in fish and chicken meat through SDS-PAGE electrophoresis

Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was applied in the detection of the end point temperature (EPT) of thermal denatured protein in fish and meat in this study. It was also used in studying the thermal denatured temperature range of proteins in salmon and chicken meat. The results show that the temperature ranges of denatured proteins were from 65 ℃ to 75 ℃ , and these temperature ranges were influenced by the processing methods. Through SDS-PAGE, the features of repeated he...     

The Effect of Temperature on Growth and Energy Budget of the Polychaete,Neanthes japonica Izuka

Growth and energy budget of the polychaete, Neanthesjaponica, at various temperatures (17, 20, 23, 26 and 29 ℃) were investigated in this study. The growth, as indicated by final dry weight and specific growth rate (SGR), increased with increasing temperature, with the maximum level at 26℃, and then decreased significantly at 29℃. A similar trend was observed in feeding rate, food conversion efficiency (FCE) and apparent digestive rate (ADR). However, no significant differences were detected in ADR among all the temperature treatments. In the pattern of energy allocation, faeces energy was only a small component of energy budget and had little influence on the proportion of food energy allocated to growth. The metabolic energy accounted for a large portion of energy intake for each temperature treatment. The nitrogen excretion was appreciable with changing temperature. The two expendi-ture terms (respiration energy and excretion energy) in energy budget were the major factors influencing the proportion of food en-ergy allocated to growth. These results revealed that temperature affected the growth of N. japonica mainly by influencing feeding rate and FCE. In addition, regression equations describing the relationship between feeding rate, faecal production, SGR, FCE and temperature were obtained. The optimum temperatures for feeding rate, FCE and SGR were estimated at 25.01 ℃, 24.24℃ and 24.73 ℃, respectively, from the regression equations.     

东营凹陷低渗透油藏分布规律及储层改造效果

东营凹陷2001年之前探明的低渗透油藏主要分布在洼陷带、中央背斜带及北部陡坡带,以沙三段深水浊积扇及沙四段滨浅湖相砂岩滩坝、扇三角洲前缘等沉积体系为主。油藏类型主要是岩性油藏,其次为构造—岩性复合型油藏。低渗透油藏以中深层、常压-超高压、低产、中产为特征,多为特小型、小型油藏,储量丰度为低丰度~特低丰度。低渗透油藏的探井试油过程中,经历了从酸化逐步到压裂的技术发展过程。统计探井的试油效果表明,沙四段碳酸盐含量较高的砂岩低渗透油藏,酸化效果较好;黏土含量较高的沙三段低渗透油藏,压裂效果较好。