多次强震单个发震概率的预测

本文提出了应用复杂记忆概率预测模型，对预测时段内发生多次地震的各次概率的计算方法。对华北北部地区（３９°─４１°Ｎ，１１４°─１１７°Ｅ）１９９５年至２００５年１０年内发生６级以上地震的概率进行了预测，结论是发生一次大于６级地震的概率为０．８５；在一定的假设条件下计算第一次地震后发生第二次６级以上地震的概率为０．２４；第三次６级以上地震的发生概率为０．０１。     

2005年前中国大陆地震震级概率预测

采用以地震震级-频度关系和贝努利随机独立试验模型为基础建立的地震震级概率预测方法，对2005年前中国大陆各地震带的地震危险性进行了预测．结果表明，2005年前，中国大陆东部各地震带发生5级地震的概率一般在0.7以上，大部分在0.8以上；各地震带发生6级地震的概率一般在0.5～0.7之间；7级地震发生的概率也以山西地震带最高，可达0.0858．2005 年前中国大陆西部各地震带普遍具有发生6级地震的可能性(一般达0.9以上)；发生7级地震的可能性在青藏高原周缘各地震带和南天山地震带相对较高(0.7以上)．本文最后对预测结果的可信度、预测概率大小与未来地震的年发生率之间的关系进行了讨论．      

汾渭和华北平原带地震发生的非稳态泊松过程与中长期概率预测

在描述事件非稳态泊松过程基本统计特征的基础上,将非稳态泊松过程应用在华北地震区汾渭带和华北平原地震带的中长期地震预测研究中。研究表明,假定未来几百年间,汾渭带和华北带的强震（Ｍ≥７．０）活动将重现上一次地震轮回的非稳态泊松时间过程,那么,在２０１０年前发生一次７级地震的累计概率分别为０．２６（不确定性范围为０．０６￣０．５０）和０．０４（不确定性范围为０．００￣０．１３）。它们明显地低于按稳态泊松     

滇西南地区五年内大震形势预测

本文采用极值理论、线性预测和最大熵谱分析三种不同的概率统计预报方法，从不同的角度对滇西南地区地震活动进行研究，得到滇西南５年内将有１次６．５－６．９级地震活动，１９９２年有６．０－６．４级发震可能的中短期预报结果。     

地城发生非稳态泊松过程和中长期概率预测研究

在描述事件非稳态泊松过程的基本统计特征及其与稳态泊松过程判别的基础上,将非稳态泊松过程应用在华北地震区分渭带和华北平原地震带的中长期地震预测研究。研究表明,假定未来几百年间,汾渭带和华北平原带的强震（Ｍ≥７．０）活动,将重现上一次地震轮回的非稳态泊松时间过程,那么,在２０１０年前它们发生一次７级大地震的累计概率分别为０．２６（不确定性范围：０．０６￣０．５０）在０．４（不确定性范围：０．００￣０．     

自组织临界现象和重整化群方法在中期地震预报中的应用研究

本文讨论了大震前的自组织临界现象，认为在大地震发生前地壳处于自组织临界状态。不同规模的地震反映地壳中不同尺度裂隙的产生或扩展。设ｐ０，ｐ１，．．．，ｐｎ是不同尺度岩石块体中产生或扩展裂隙的概率，根据重整化群理论，数列｛ｐ０，ｐ１，．．．ｐｎ｝有极限。其极限值可能是０或１。选定一个临界值ｐ，如果ｐ０＞ｐ，则ｐｎ－１；反之，若ｐ０－ｐ。在本文中，作者根据地震资料研究了青藏高原北部地区的临界概率ｐ值，得     

江苏-南黄海地区未来地震形势的统计分析

根据１５００年以来的地震资料,应用数理统计、灰色预测、干支６０周期分析等多种方法,对江苏—南黄海地区未来３～５年地震形势进行分析和预测,结果表明：该区目前处于本世纪第２活跃幕中后期,未来几年内依然存在５～６级地震的危险性,至２０００年７月,累积发震概率将达到０．７～０．８,１９９９—２０００年、２００２—２００３年均有可能发生５级以上中强地震。     

中长期时空增益综合预测模型及其初步应用

阐述了中长期地震时空增益综合预测模型的基本原理和单项预测方法的信度评价方法,给出了概率增益与预测效能评分R值的关系,并对R值评分法进行了推广．以华北地区为试点,研究了不同地震活动期与活动幕的时间概率增益、活断层的空间概率增益和以垂直形变为代表的时空联合的概率增益,并采用中长期地震时空增益综合预测模型,对华北北部地区的综合概率增益进行了示例性预测．      

安徽与周边地区地震活动关系的研究

在对中国大陆东部与银川地震带及安徽地区地震活动周期进行划分与研究的基础上，将安徽与周边特定地区每周期的地震活动，划分为２４个时空序次。分析研究安徽４个地城与周边特定地区２０个地震时空序次的关系，预测未来几年内安徽中西部地区可能发生Ｍｓ５．０～５．７５地震。     

青海地区强震活动的统计分析及预报探讨

从统计的角度出发，研究了青海地区１９９３年Ｍ≥６强震的发生概率，在此基础上应用非线性最小二乘法拟合的Ｇｏｍｐｅｒｔｚ与Ｌｏｇｉｓｔｉｃ曲线模型以及可公度模型对该区Ｍ≥６．５强震进行了预测探索。结果表明，１９９３年该地区Ｍ≥６强震的发生概率将达到０．７６－０．８７，１９９３－１９９４年有可能发生Ｍ≥６．５强震。     

SCIENCE CHINA Earth Sciences SUBJECT INDEX TO VOLUME 57(2014)

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Distribution of throughfall and stemflow in multi‐strata agroforestry,perennial monoculture,fallow and primary forest in central Amazonia,Brazil

The partitioning of rain water into throughfall, stemflow and interception loss when passing through plant canopies depends on properties of the respective plant species, such as leaf area and branch angles. In heterogeneous vegetation, such as tropical forest or polycultural systems, the presence of different plant species may consequently result in a mosaic of situations with respect to quantity and quality of water inputs into the soil. As these processes influence not only the water availability for the plants, but also water infiltration and nutrient leaching, the understanding of plant effects on the repartitioning of rain water may help in the optimization of land use systems and management practices. We measured throughfall and stemflow in a perennial polyculture (multi‐strata agroforestry), monocultures of peach palm (Bactris gasipaes) for fruit and for palmito, a monoculture of cupuaçu (Theobroma grandiflorum), spontaneous fallow and primary forest during one year in central Amazonia, Brazil. The effect on rain water partitioning was measured separately for four useful tree species in the polyculture and for two tree species in the primary forest. Throughfall at two stem distances, and stemflow, differed significantly between tree species, resulting in pronounced spatial patterns of water input into the soil in the polyculture system. For two tree species, peach palm for fruit (Bactris gasipaes) and Brazil nut trees (Bertholletia excelsa), the water input into the soil near the stem was significantly higher than the open‐area rainfall. This could lead to increased nutrient leaching when fertilizer is applied close to the stem of these trees. In the primary forest, such spatial patterns could also be detected, with significantly higher water input near a palm (Oenocarpus bacaba) than near a dicotyledonous tree species (Eschweilera sp.). Interception losses were 6·4% in the polyculture, 13·9 and 12·3% in the peach palm monocultures for fruit and for palmito, respectively, 0·5% in the cupuaçu monoculture and 3·1% in the fallow. With more than 20% of the open‐area rainfall, the highest stemflow contributions to the water input into the soil were measured in the palm monocultures and in the fallow. Copyright © 1999 John Wiley & Sons, Ltd.     

A Monte Carlo study of rainfall forecasting with a stochastic model

A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities.     

Anthropogenic Eutrophication and Red Tide Outbreak in Lacustrine Systems of the Kashmir Himalaya

Red tide, a recurrent phenomenon has become conspicuous in several Kashmir lake ecosystems since 1991. The responsible organism (Euglena pedunculata), a rare flagellate rediscovered in the Kashmir Himalaya (Khan 1993) caused first and unprecedented red tide outbreak, constituting a maximum of 96% of resident numerical phytoplankton density in Dal Lake. At present, conflicting hypotheses exist on the generation of causal assemblage(s) imparting redness to waters: Jeeji Bai (1991) linked its origin to acid precipitation – a fallout of burning oil‐fields during the Gulf War – whilst Khan (1993) holds local factor(s) responsible. Field/experimental studies support the latter contention that the influx of untreated sewage, in unison with warm temperatures, high levels of PhAR, iron and interruption to hydrological flow‐pattern together with absence/or reduction in grazing activity created conducive environmental milieu for red tide outbreak. Dal Lake “red tide” drifted the bloom‐inoculum to other waters, including Lake Wular, where additional ecological niches were carved out, threatening the aesthetic value and biological diversity of Kashmir lakes. Ecological monitoring indicates frequent seasonal red tide occurrence in Dal Lake (including summer‐autumn event of 1998) which testifies its unabated eutrophication status. Further studies are needed on ecological adaptability and biogeographic distribution of this rare and unique red tide‐causing flagellate.