再论甘蔗蔗糖份和成熟期自然气象要素的关系

本文以方差分析研究闽中、闽南蔗区82/83年和83/84年两个榨季甘蔗蔗糖份和成熟期间自然气象要素的关系。闽中(仙游)和闽南(泉州、漳州、厦门、云霄)五个糖厂的全榨季平均甘蔗蔗糖份,82/83年榨季再次下降和83/84年榨季全面回升与工艺成熟期间自然气象要素的异常和好转十分默契,再次确认起主导作用的是气象要素。本文还简略地讨论了预防或减轻异常气象要素对甘蔗蔗糖份不利影响的技术措施。     

甘蔗蔗糖份和成熟期间自然气象要素的关系

本文以相关分析和方差分析,研究闽中闽南蔗区甘蔗蔗糖份和成熟期间自然气象要素的关系。认定甘蔗工艺成熟的九、十月份,是由茎叶伸长生长为主,转入蔗糖份积累为主、关键性的生理转析时期。在自然情况下,对蔗糖份积累起限制性作用的气象要素,是日照时数和雨量。81/82年榨季,闽中(仙游)、闽南(泉州、漳州、厦门、云霄)五个糖厂蔗区的全榨季平均甘蔗蔗糖份的降低,和工艺成熟期间发生自然气象要素的异常程度相一致。确认蔗糖份下降,起主导作用的,是气象要素的异常。本文还提出五个糖厂蔗区的全榨季平均甘蔗蔗糖份的正常变化范围,以供查明正常与异常年份之参考。     

正镶白旗地区2009年冬季异常气候特征分析

针对2009年冬季(2009年11月至2010年2月)正镶白旗地区出现的异常气候,分析气温、降水、积雪等气象要素的特征,以及异常气候带来的影响。提出防御措施,以降低异常气候带来的不利影响。     

甘肃历史地震与气象异常相关性研究之二——隋唐宋元时期

阐述分析了隋唐宋元时期,今甘肃地区白虹贯日、雷发非时、异常大风、异常旱涝和生物异常等与地震的密切关系,进一步研究得出除气象异常外,地震前后还有天象异常、地象异常与水象异常的现象,且地震前后异常现象也不仅仅限于一种,常具有多发特征。最后提出,利用地震与气象异常关联性原理进行中期地震预报与短、中期气象预报时,应该遵循多证据复合原则。     

地震前兆的复杂性与地震预报

地震前兆与地震关系的确认是地震预报的关键因素。本文从地震预测和地震前兆异常两个方面系统地介绍了国内外的观测结果和研究成果，并在此基础上初步探讨了前兆异常和地震之间的关系；结合具体的地震观测资料，介绍了地震前兆的多样性以及地震成因的复杂性，进一步阐述了地震预报研究过程中遇到的困难和产生的新问题。     

近64年重庆地区夏季高温分析

利用重庆14个气象观测站1951—2014年夏季逐日气温观测资料,运用二项式系数加权平均、EOF等方法,详细探讨了重庆夏季高温日数和极端最高气温事件的时间、空间分布特征。结果表明,近64年来重庆地区的高温日数具有显著的年际变化和地域差异。重庆夏季高温的异常空间分布有4个关键区,分别为重庆西部、重庆中部、重庆东北部以及重庆东南部。     

2009年济阳县气候影响评价

分析2009年济阳县的气象要素、灾害性天气,与常年进行比较和评价,研究气象要素对农业、人民生活的影响,指出2009年济阳县的气候年景为平年。     

2014年普兰店市夏季干旱对农作物的影响及抗旱措施

2014年夏季普兰店地区降水量异常偏少,出现了严重的干旱,大部分农作物遭受旱灾,通过分析夏季气象要素对农作物的影响,提出为防御旱情,切实加强农作物田间管理的抗旱措施,以期将气象灾害损失降到最低。     

重庆主城区云量变化特征

利用1951-2011年重庆沙坪坝站的总云量、低云量、平均气温、降水量、日照时数和相对湿度等气象资料, 采用趋势分析、小波及相关等方法分析了重庆主城区总云量和低云量的变化特征及其与主要气象要素的关系,结 果表明:整个时间域内主城区年及春、夏、秋三季的总云量总体减少,其中秋季减少最为明显,而冬季则略有增加 的趋势;年及四季的低云量总体呈增加趋势,夏季和冬季增加相对明显.低云量的年际变化幅度大于总云量,但两 者年际和年代际变化趋势比较一致,阶段性特征大体上体现为20世纪50年代至70年代云量相对偏少,80年代至 90年代相对偏多,之后至今处于相对偏少的阶段.总云量年及各季节(除夏季外)均在20世纪90年代发生转折;而 低云量年及各季发生了2次转折,分别在1964年和2005年前后(夏季除外).总云量1月、2月、10月和12月较 多,8月最少;低云量最多的是12月,8月最少.总云量和低云量冬季最多,其次为秋季和春季,最少的是夏季.总 云量和低云量与平均气温、日照时数和相对湿度等气象要素关系显著,但与降水量的关系总体不太明显;冬季云量 和平均气温等气象要素的相关不太显著,其它季节云量和平均气温、日照时数及相对湿度显著相关.     

塔斯尔海垦区棉花适宜播期气候要素分析

利用塔斯尔海气象观测站2002—2011年气象资料探讨了3月下旬至4月下旬棉花播种关键期的气候背景,对棉花播种影响较大的气象要素和异常天气等进行深入分析,结果表明:在塔斯尔海垦区棉花播种关键时期,4月上旬气温偏低的概率较大;终霜冻异常偏晚,基本为3年一遇;每年的降水概率均很高;大风灾害少;据此可以确定最佳播种期。     

基于信息熵的县域土地利用结构变化与分布研究

信息熵是对系统的不确定性(无序性)的一种量度,其演变在一定程度上可以反映区域各类土地利用类型的动态演变规律,也可以反映区域土地的分布。根据信息熵原理研究了重庆市荣昌县土地利用结构变化及分布,并与重庆市进行了比较。结果表明,从时间变化看,荣昌县土地利用结构信息熵在1996~2005年一直处于上升状态,1996年土地利用结构信息熵最低,为1.306 5,2005年达到最大值1.450 8,正处于"凸"型非线性增加态势;从空间变化看,信息熵的大小与经济发展水平密切相关,信息熵大,经济发展较好。荣昌县土地利用信息熵比重庆市水平低,且二者变化趋势差别很大,重庆市信息熵波动较大。     

甘肃历史地震与气象异常相关性研究之一——两汉三国魏晋南北朝时期

两汉至南北朝时期,气象灾异频次与地震频次之间存在着明显关联。从今甘肃地区发生的地震看,白虹贯日、雷发非时等异常气象与地震的关系最为密切,与地震关联的异常气象还有天雨血、黑气、青虹等,地震前后异常现象还具有多发特征。     

“9.5”泸定地震对土壤物理性质及其碳储量的影响

2022年9月5日,四川省甘孜藏族自治州(简称甘孜州)泸定县发生6.8级地震,此次地震造成了周边区域水土流失加剧,生态状况急剧恶化。因此,本研究以受“9.5”泸定地震影响产生山体滑坡的林地作为研究对象,以附近未受地震影响的、林分结构相近的林地作为对照,分析地震对林地土壤物理性质及其碳储量的影响。结果表明,0-5和5-10cm土层均表现为滑坡后土壤的孔隙度、毛管持水量均低于未滑坡土壤,容重、非毛管孔隙度高于未滑坡土壤,碳储量则低于未滑坡土壤。综上所述,地震产生的滑坡会对土壤的物理结构产生影响,进而减少土壤的有机碳储量。     

Interaction of the san jacinto and san andreas fault zones, southern california: triggered earthquake migration and coupled recurrence intervals

Two lines of evidence suggest that large earthquakes that occur on either the San Jacinto fault zone (SJFZ) or the San Andreas fault zone (SAFZ) may be triggered by large earthquakes that occur on the other. First, the great 1857 Fort Tejon earthquake in the SAFZ seems to have triggered a progressive sequence of earthquakes in the SJFZ. These earthquakes occurred at times and locations that are consistent with triggering by a strain pulse that propagated southeastward at a rate of 1.7 kilometers per year along the SJFZ after the 1857 earthquake. Second, the similarity in average recurrence intervals in the SJFZ (about 150 years) and in the Mojave segment of the SAFZ (132 years) suggests that large earthquakes in the northern SJFZ may stimulate the relatively frequent major earthquakes on the Mojave segment. Analysis of historic earthquake occurrence in the SJFZ suggests little likelihood of extended quiescence between earthquake sequences.     

Clustering and periodic recurrence of microearthquakes on the san andreas fault at parkfield, california

The San Andreas fault at Parkfield, California, apparently late in an interval between repeating magnitude 6 earthquakes, is yielding to tectonic loading partly by seismic slip concentrated in a relatively sparse distribution of small clusters (<20-meter radius) of microearthquakes. Within these clusters, which account for 63% of the earthquakes in a 1987-92 study interval, virtually identical small earthquakes occurred with a regularity that can be described by the statistical model used previously in forecasting large characteristic earthquakes. Sympathetic occurrence of microearthquakes in nearby clusters was observed within a range of about 200 meters at communication speeds of 10 to 100 centimeters per second. The rate of earthquake occurrence, particularly at depth, increased significantly during the study period, but the fraction of earthquakes that were cluster members decreased.     

重庆市农作物生长季干旱时空分布规律研究

利用重庆市11个国家气象站1960-2013年的逐日降水量资料,按照《重庆市气象灾害标准》统计1960-2013年农作物生长季的干旱次数和强度,并采用数理统计、地统计分析、小波分析等方法,研究重庆市农作物生长季干旱时空分布规律.结果表明:干旱发生次数年代际差异明显,且干旱长期变化具有阶段性和周期性;近10年来,高强度等级干旱发生频率有上升趋势;重庆市干旱主要发生在渝西南地区和中部地区以及渝东北地区.研究成果可为重庆市不同区域农作物布局和防旱避灾提供科学依据.     

Tilt Precursors before Earthquakes on the San Andreas Fault, California

An array of 14 biaxial shallow-borehole tiltmeters (at 1O(-7) radian sensitivity) has been installed along 85 kilometers of the San Andreas fault during the past year. Earthquake-related changes in tilt have been simultaneously observed on up to four independent instruments. At earthquake distances greater than 10 earthquake source dimensions, there are few clear indications of tilt change. For the four instruments with the longest records (> 10 months), 26 earthquakes have occurred since July 1973 with at least one instrument closer than 10 source dimensions and 8 earthquakes with more than one instrument within that distance. Precursors in tilt direction have been observed before more than 10 earthquakes or groups of earthquakes, and no similar effect has yet been seen without the occurrence of an earthquake.     

The loma prieta, california, earthquake: an anticipated event

The first major earthquake on the San Andreas fault since 1906 fulfilled a long-term forecast for its rupture in the southern Santa Cruz Mountains. Severe damage occurred at distances of up to 100 kilometers from the epicenter in areas underlain by ground known to be hazardous in strong earthquakes. Stronger earthquakes will someday strike closer to urban centers in the United States, most of which also contain hazardous ground. The Loma Prieta earthquake demonstrated that meaningful predictions can be made of potential damage patterns and that, at least in well-studied areas, long-term forecasts can be made of future earthquake locations and magnitudes. Such forecasts can serve as a basis for action to reduce the threat major earthquakes pose to the United States.     

The 1985 central chile earthquake: a repeat of previous great earthquakes in the region?

A great earthquake (surface-wave magnitude, 7.8) occurred along the coast of central Chile on 3 March 1985, causing heavy damage to coastal towns. Intense foreshock activity near the epicenter of the main shock occurred for 11 days before the earthquake. The aftershocks of the 1985 earthquake define a rupture area of 170 by 110 square kilometers. The earthquake was forecast on the basis of the nearly constant repeat time (83 +/- 9 years) of great earthquakes in this region. An analysis of previous earthquakes suggests that the rupture lengths of great shocks in the region vary by a factor of about 3. The nearly constant repeat time and variable rupture lengths cannot be reconciled with time- or slip-predictable models of earthquake recurrence. The great earthquakes in the region seem to involve a variable rupture mode and yet, for unknown reasons, remain periodic. Historical data suggest that the region south of the 1985 rupture zone should now be considered a gap of high seismic potential that may rupture in a great earthquake in the next few tens of years.