大沙鼠的警戒行为与采食及其它行为之间的关系

动物常依据捕食风险强弱改变其行为策略,在警戒与采食及其它行为的时间分配上权衡,这一理论称为捕食风险的时间分配假说。该假说已在高原鼠兔等动物中得到验证,但对在中亚荒漠地区有代表性的啮齿动物大沙鼠(Rhombomys opimus)是否成立至今未被验证。通过行为观察,比较警戒与采食等行为在单位观察时间内总累积时间、单次行为持续时间以及活动频次之间的关系,验证大沙鼠行为规律是否符合捕食风险的行为时间分配假说。结果显示大沙鼠警戒行为的总累积时间与采食等其它行为间存在显著负相关(警戒与总地表活动:r=-0.727,P<0.001;警戒与采食:r=-0.515,P<0.001;警戒与储食:r=-0.174,P<0.001;警戒与其它行为:r=-0.142,P=0.001),警戒单次持续时间也与其它行为的单次持续时间存在显著负相关(警戒与地表活动:r=-0.157,P<0.001;警戒与采食:r=-0.126,P=0.002;警戒与储食:r=-0.094,P=0.024)。此外大沙鼠警戒频次与其活跃程度紧密相关,大沙鼠活动频繁时,伴随的警戒次数也多(警戒与总地表活动:r=0.404,P<0.001;警戒与采食:r=0.311,P<0.001;警戒与储食:r=0.297,P<0.001;警戒与其它行为:r=0.366,P<0.001)。研究表明:大沙鼠在警戒与采食等其它行为的时间分配上存在明显权衡,支持捕食风险的时间分配假说,并且其警戒行为亦与活动频次有关,当大沙鼠活动频繁时,伴随的警戒行为次数也越多。

全新世以来腾格里沙漠风沙活动地质记录与模拟数据综合研究

自晚更新世以来,地处干旱与半干旱过渡区的腾格里沙漠,在亚洲季风的作用下,经历了几度流沙出现、扩大和固定、半固定乃至弱成壤的沙漠正、逆交替变化过程。东亚季风在时空尺度上的强弱变化通常被解释为驱动腾格里沙漠环境变化的主要原因。用于重建古环境和风沙活动的变化多依赖于腾格里沙漠边缘区域的黄土、湖泊、孢粉和冲洪积物,然而涉及到沙漠腹地的古环境记录较少,并且不同地点的沉积剖面所记录的地质信息具有区域局限性。本研究在腾格里沙漠西南边缘至腹地采取4个典型风沙沉积序列,共采集97个沉积样品和11个风沙沉积物光释光年代数据,并收集整理了约14 ka以来已发表的69个风沙沉积物光释光年龄数据以及137个古土壤、湖相沉积物和钙质根管的14C年龄数据;另外,为了减少沉积序列在解读和重建沙漠环境演变的或然性,运用TraCE-21 ka古气候模拟数据分别计算了14 ka以来腾格里沙漠地区地表有效湿度和沙丘活化指数的变化趋势,以及春冬和夏秋季节沙丘活化指数对全年平均值的贡献量,综合探讨了全新世以来腾格里沙漠近地表风沙活动历史以及驱动因素。结果表明:1)早全新世时期(11.7~8.0 ka),较粗的平均粒径和偏多的风沙年代数据表明该时期风沙活动较强;模拟数据结果显示该时期风沙活动呈现减弱趋势,这主要是由于减弱的东亚冬季风引起的近地表风速下降所导致的,从而发生大量的风沙堆积;2)中全新世时期(8~3 ka),较高的低频磁化率和较多的14C年代数据指示该时期古土壤发育,地表湿润条件转好,风沙活动较弱。模拟数据结果表明该时期地表有效湿度较高,风沙活动处于较低水平,这主要是由于增强的东亚夏季风带来了大量的降水,促使地表有效湿度较高,沙丘逐渐被植被固定;3)晚全新世以来(3~0 ka),较粗的平均粒径和风沙年代数据增多表明风沙活动再次活跃。模拟数据结果显示该时期风沙活动呈现增加趋势,表明东亚夏季风减弱和腾格里沙漠的气候干旱导致沙漠地表有效湿度逐渐下降,植被退化,固定沙丘再度活化。

河北省地裂缝灾害与成因分析

３０年来在河北省及其包容的京津地区出现地裂缝４５３条（处）．损坏民房千余处，楼房３０幢，造成管道破裂，道路变形，上千处农田漏水，经济损失数以亿计。调查表明，大多数地裂缝是闭合的土层构造节理开启，又在地表水下渗，冲刷这一决定性的诱发因素作用下延至地表显现成缝，次为断层蠕动在地表的反映；少数为重力作用的产物。

蝼蛄的发生规律及防治措施

蝼蛄俗名“拉拉蛄”，是咬食作物地下根茎部及种子的多食性地下害虫，几乎危害所有作物。在我国危害最重的是华北蝼蛄和东方蝼蛄，经常将植株咬成乱麻状，或在地表活动，钻成隧道，使种子、幼苗根系与土壤脱离不能萌发、生长，进而枯死，造成缺苗断垄或植株萎蔫停止发育。

意大利科学家在地球深处发现反中微子

据美国趣味科学网站6月26日报道,意大利科学家表示,他们在地球内部很深的地方探测到了反物质粒子,这些粒子可能源于地球内部的放射性衰变,研究这些粒子,有助于科学家更好地理解地球内部的热流如何影响火山和地震等地表活动。

“废土”题材的伏特加风范 地铁：最后的曙光

本作的故事紧接《地下铁2033》的结尾，此前的小P孩男主角Artyom发射核武，毁灭了莫斯科地表活动的变异生物“黑怪“（Dark Ones）。然而“和谐弹”在往这片废土之上再次种了一朵硕大的蘑菇之后，

小麦孕穗期可撒药土防治吸浆虫

小麦吸浆虫以老热幼虫在深层土壤中结圆茧越冬，并且可以休眠多年，春季当10厘米土温上升到7cc左右时，也就是小麦拔节期开始破茧和向土壤表层移动，4月中旬小麦进入孕穗期，幼虫陆续在3厘米表土层中做土室化蛹。蛹期一般8～12天。4月下旬，成虫羽化后先在地表活动，然后在麦穗上产卵，此时正值小麦抽穗期至扬花期，卵期3～7天。孵化出的幼虫钻进麦穗颗壳内，咬破麦粒表皮，吸食正在灌浆的麦粒浆液，造成秕粒、空壳。

水晶——水之精灵

一、水晶的形成水晶的主要成分是二氧化硅，硬度在摄氏70度，密度在265左右，具有双折射的特点。几年万年前，地球的岩浆从地心向地表活动，其中含有二氧化硅的岩浆钻入泥土，岩石中的空穴，慢慢结晶成为今日之水晶。水晶在中国最古老的叫法是“水玉”，意谓似水之玉。佛书中则称莹沽晶光的水晶为“水之精灵”，认为水晶会闪烁神奇的灵光，可普渡众生，尊称水晶为“菩萨石”。

春季如何防治麦田地下害虫

冬小麦在秋苗期和返青后会受到多种地下害虫的危害，其中蛴螬在近几年有持续发展的趋势，而金针虫在洼区或灌区则有所回升。 1 发生规律 春季麦田地下害虫以金针虫、鲜黄金龟甲发生最早，一般在2月下旬～4月上旬，当10cm地温上升到6℃以上时，就移到地表活动，为害小麦分蘖节，造成小麦成丛死苗：4月上中旬，地温到8℃～10℃以上时，

Time series prediction of mining subsidence based on a SVM

In order to study dynamic laws of surface movements over coal mines due to mining activities,a dynamic prediction model of surface movements was established,based on the theory of support vector machines(SVM) and times-series analysis.An engineering application was used to verify the correctness of the model.Measurements from observation stations were analyzed and processed to obtain equal-time interval surface movement data and subjected to tests of stationary,zero means and normality.Then the data were used to train the SVM model.A time series model was established to predict mining subsidence by rational choices of embedding dimensions and SVM parameters.MAPE and WIA were used as indicators to evaluate the accuracy of the model and for generalization performance.In the end,the model was used to predict future surface movements.Data from observation stations in Huaibei coal mining area were used as an example.The results show that the maximum absolute error of subsidence is 9 mm,the maximum relative error 1.5%,the maximum absolute error of displacement 7 mm and the maximum relative error 1.8%.The accuracy and reliability of the model meet the requirements of on-site engineering.The results of the study provide a new approach to investigate the dynamics of surface movements.

Effect of a combined inversion and plantarflexion surface on ankle kinematics and EMG activities in landing

Purpose： The purpose of this study was to examine the effects of landing kinematics and electromyographic （EMG） activities of medial gastrocnemius on a combined inversion and plantarflexion surface on the ankle （MG）, peroneus longus （PL）, and tibialis anterior （TA） muscles. Methods： Twelve recreational athletes performed five drop landings from an overhead bar of 30 cm height on to three surfaces： a flat surface, a 25° inversion surface, and a combined surface of 25° inversion and 25° plantarflexion. The kinematic variables and integrated EMG （IEMG） of the three muscles were assessed using a one-way repeated measures ANOVA and a 3 × 3 （surface × muscle） ANOVA, respectively （p 〈 0.05）. Results： The IEMG results showed a significant muscle by surface interaction. The flat surface induced higher TA activity than the two tilted surfaces. The inverted surface produced significantly higher inversion peak angle and velocity than the flat surface, but similar PL activity across the surfaces. The MG IEMG, ankle plantarflexion angle, and inversion range of motion were significantly higher for the combined surface compared to the inverted surface. Conclusion： These findings suggest that compared to the inversion surface, the combined plantarflexion and inversion surface seems to provide a more unstable surface condition for lateral ankle sprains during landing.

Implication of Surface Fractal Analysis to Evaluate the Relative Sensitivity of Topography to Active Tectonics,Zagros Mountains, Iran

Fractal geometry is increasingly becoming a useful tool for modeling and quantifying the complex patterns of natural phenomena. The Earth's topography is one of these phenomena that have fractal characteristics. This paper investigates the relative sensitivity of topography to active tectonics using ASTER Global Digital Elevation Model. The covering divider method was used for direct extraction of surface fractal dimension(D surf) to estimate the roughness-surface of topography with aid of geographic information system(GIS)techniques. This evaluation let us highlight the role of the geomorphic and tectonic processes on the spatial variability of fractal properties of natural landforms.Geomorphic zones can be delineated using fractal dimension mapping in which variability of surface fractal dimension reflects the roughness of the landform surface and is a measure of topography texture. Obtained results showed this method can be a quick and easy way to assess the distribution of land surface deformation in different tectonic settings. The loose alluvial deposits and irregularities derived by tectonic activity have high fractal dimensions whereas the competent formations and higher wavelength folded surfaces have lower fractal dimensions.According to the obtained results, the Kazerun Fault Zone has a crucial role in the separation of the Zagros Mountain Ranges into the different lithological,geomorphological and structural zones.

Climate Change and Environmental Impact Caused by Anthropogenic

For the last two decades the world has undergone a population explosion which has been accompanied by a speeding up of urbanization and land use for industrial and agricultural products. These involve a vast increase in the discharge of pollutants into very different receiving water bodies, and have had adverse effects on the various components of the environment. For a long time, human has concerned a little of the natural environment. It is obvious that this variation in surface temperature of the earth increases the level of sea due to snowmelt. So climate change is manifested by many phenomena： floods, droughts, fires, tornadoes, cyclones, earthquakes, volcanic eruptions, diseases etc.. The statement today is dramatic. Entire regions were devastated and many rivers and lakes have become polluted around the world. Pollution has it nature which is hard to be absorbed. Where did the different pollutants come from？ What are the risks to the aquatic environment？ To prevent and combat the general decline of these ecosystems, it is important to distinguish and determine the effects of different sources of pollution and any changes that may suffer the physical environment. The climate depends primarily on changes in earth orbit parameters, which affect the solar radiation received by the earth surface. Therefore, human participates strongly to these changes, for example, pollution is the main reason to argue the greenhouse effect, an increase of anthropogenic carbon dioxide （CO2） into the atmosphere, which promotes global warming to the planet. These modifications are already applied in order to ensure durable development in water resources by controlling discharges into streams to preserve water resources for future generations and to ensure reconciliation between man-climate and environment.

Characteristics of Late Quaternary Activity of the Gadê Segment in the Madoi-Gadê Fault Zone

Madoi-Gade fault is an active fault in the Bayan Har block. According to field investigation, there is an earthquake surface rupture fairly well preserved on the Gade segment of the Madoi-Gade fault zone. The length of the rupture is approximately 50km, with a general strike of NW. The maximum horizontal sinistral displacement is about 7.6m and the maximum vertical displacement is about 4m. A large number of earthquake traces are to be found along the rupture zone, and the phenomena on the surface rupture are also various. Field investigation and analysis on the geological and geomorphological phenomena show that the formation age of the surface rupture is relatively young. A series of linear arranged, triangular facets, fault scarps, fault springs, dislocated gullies, twisted mountain ridges, sag-ponds, dislocated ridges, etc. exist along the fault. Based on the analysis of field investigation and the data available, we believe that the surface rupture is due to a strong earthquake in the history of this area. And it is inferred that the Madoi- Gade fault within the Bayan Har block has been highly active since Late Quaternary and may still be active nowadays.

Monitoring of Ionizing Radiation and Rain Intensity during May to October 2015 in S^o Jos~ dos Campos, Brazil

Radiation affects the environment and local human activity in any location of the earth＇s surface. Due to this fact, the aim of this study was to monitor the ionizing radiation and rain intensity using portable devices. During May 23 to October 2, 2015, it was made measures the intensity of gamma radiation from 30 keV to 10.0 MeV at a height of 25 meters in Sao Jos6 dos Campos city, SP, Brazil. It was used a crystal of sodium iodide scintillator 3 - 3 inches coupled to a photomultiplier and associated electronic. The measurements were made continually with minute＇s interval throughout the period and it was monitored rain intensity every minute at the same height of the tower. In this job, it was possible to correlate rain-radiation and it was observed which gamma radiation has a directly proportional relationship with rain and visible frequency of 1 day.

Learning and Progressing Through Scientific Practices—Commemorating the 90th Anniversary of the Haiyuan Earthquake and Working to Improve the Ability of Earthquake Prediction and Seismic Hazard Reduction

The great Haiyuan earthquake occurred at 20:06:09 on December 16,1920 in the south of Ningxia Hui Autonomous Region.The magnitude of this earthquake is 8.5,listed as one of the three greatest earthquakes to ever occur in Chinese continent.This devastating earthquake killed about 230,000 people according to previous reports.Recent studies show that total casualties may have reached 270,000.The study of this earthquake using modern scientific and technological methods is the first in the history of earthquake research in China.Significant breakthroughs took place in the middle of last century.The earthquake surface rupture,with 200km in length and prominent left-lateral strike-slip displacement,was discovered.The first monograph on the Haiyuan earthquake was published.In the 1980s,innovative large-scale geological mapping technology for active faults was developed during studies on the Haiyuan earthquake surface ruptures,with the publication of the first large-scale map of the Haiyuan active fault.Quantitative studies were carried out on the fine structure and geometry of the fault zone,Holocene slip rate,co-seismic displacement,paleoearthquake and recurrence intervals and future earthquake risk assessment.The innovative studies also included rupture propagation along the strike-slip fault,evolution of pull-apart basins,determination of total displacement of the strike-slip fault,transition equilibrium between strike-slip displacement along its major strand and crustal shortening at the end of the strike-slip fault,and the mechanism of deformation on Liupan Mountain.On the occasion of the 90th anniversary of the Haiyuan earthquake,careful retrospect of scientific progress achieved during the recent 20 years would be helpful in providing further direction in the study of active faults and earthquake hazard reduction.While taking this occasion to remember those lost by the Haiyuan earthquake,we aim to make greater contributions to earthquake prediction and seismic hazard reduction.

5亿年前的寄居节肢动物

美国威斯康辛州麋鹿丘群所在的地区在晚寒武纪的时候是潮间带沙滩。当时这里的沙滩上覆盖着一层微生物生长形成的膜。虽然这样的环境不容易保存矿化的生物实体化石，但却可以很好地记录当时宏观动物在地表活动的痕迹。最近，研究者根据这里记录的痕迹发现了5亿年前节肢动物应对潮间带潮涨潮落的生存策略——像寄居蟹一样利用其他生物的壳。