Relationships of growth and mortality to enzymatic activity,and the relative mRNA expression of cultured scallops Patinopecten yessoensis in the Yellow Sea,China

The bottom aquaculture of yesso scallop (Patinopecten yessoensis) has developed rapidly in the north of Yellow Sea, China, but not without accompanying productivity problems. We, therefore, conducted field surveys to investigate factors related to growth and mortality rates of bottom-cultured scallops after release. Specifically, we focused on the effects of total antioxidant capacity (TAOC) and three key enzymes involved in antioxidant and metabolic function:glutamic pyruvic transaminase (GPT), lactic dehydrogenase (LDH), and superoxide dismutase (SOD). Across summer and winter, we also measured the relative mRNA expression of GPT and SOD to understand their seasonal variation in the scallops, along with how such variation correlated to growth and mortality. Results show that bottom cultured scallops experienced mass mortality during the first six months post-release. During winter (December), scallops grew more rapidly and suffered less mortality than in summer (August). The observed lower performance probably resulted from less advantageous environmental factors during the summer seasons, such as high temperature and low dissolved oxygen. These environmental stressors enhance protein consumption while decreasing energetic resources in scallops. Furthermore, scallops in summer exhibited high antioxidant levels that probably competed for energy with process integral to growth and survival. These negative factors combined to elevate mortality rates. In conclusion, we provided evidence suggesting correlations between metabolic/antioxidant activity and growth and mortality of bottom-cultured yesso scallops. These correlations implied us an accurate method to estimate the performance of bottom culture system. Suggestions about innovative aquaculture techniques were also discussed in the study. Our results might provide a possible guideline to the improvement of bottom culture techniques for this commercially valuable seafood species.     

暴雨泥石流冲出距离预测

有效确定泥石流可能的危险范围对制定防灾减灾规划具有重要的参考价值.在对2008-09-24北川县境内发生的72处暴雨泥石流调查的基础上,通过对泥石流冲出距离的统计分析,提出了基于地貌学特征的泥石流冲出距离预测模型.模型根据泥石流沟流域面积的大小分类,给出了相应的计算取值参数范围.将该模型应用到汶川县城后山2条泥石流沟进行验证,计算结果表明,用模型预测的泥石流冲出距离比实际冲出距离稍偏大,平均误差值介于4%～11%间,这对泥石流实际冲出距离的预测是可行的.     

Determination of Abundances of Fifty‐Two Elements in Natural Waters by ICP‐MS with Freeze‐Drying Pre‐concentration

To precisely determine the abundances of fifty‐two elements found within natural water samples, with mass fractions down to fg g^?1 level, we have developed a method which combines freeze‐drying pre‐concentration (FDC) and isotope dilution internal standardisation (ID‐IS). By sublimation of H₂O, the sample solution was reduced to < 1/50 of the original volume. To determine element abundance with accuracy better than 10%, we found that for solutions being analysed by mass spectrometry the HNO₃ concentration should be > 0.3 mol l^?1 to avoid hydrolysis. Matrix‐affected signal suppression was not significant for the solutions with NaCl concentrations lower than 0.2 and 0.1 cg g^?1 for quadrupole ICP‐MS and sector field ICP‐MS, respectively. The recovery yields of elements after FDC were 97–105%. The detection limits for the sample solutions prepared by FDC were ≤ 10 pg g^?1, except for Na, K and Ca. Blanks prepared using FDC were at pg‐levels, except for eleven elements (Na, Mg, Al, P, Ca, Mn, Fe, Co, Ni, Cu and Zn). The abundances of fifty‐two elements in bottled drinking water were determined from five different geological sources with mass fractions ranging from the fg g^?1 to μg g^?1 level with high accuracy.     

梯级筑坝下小型山区河流水体碳氮磷的时空特征及富营养化风险

梯级筑坝对河流水环境演化的影响是国内外关注的热点.小型山区河流高密度梯级开发对水体生源要素的空间格局以及水环境演化的累积影响特征尚不清楚.以重庆市五布河为研究对象,对流域内8个“河流—水库—下泄水”交替系统中表层水体理化因子及碳(C)、氮(N)、磷(P)形态组成进行季节性监测,探讨了梯级筑坝对小型河流生源要素空间格局及水体富营养化风险影响的累积特征及驱动机制.结果表明：梯级水电开发对五布河流域水生生境和生源要素空间分配的影响具有潜在的累积效应,各库区水体碳氮磷浓度均呈逐级增加的空间规律;水库段的有机碳及不同形态的氮、磷浓度均高于入库河流,因此水体养分浓度呈现出河段尺度(即单个河流—水库—下泄水系统)和流域尺度(即上游至下游)耦合的空间变异模式.上游水库中溶解性氮、磷的再释放及下泄输移能够补给下游库区,加之下游水库泥沙对氮、磷的吸附—沉积作用的减弱,导致水体氮、磷总量及溶解性氮、磷的占比沿程增加,呈现梯级筑坝对水环境演化的累积影响.梯级筑坝影响下河流碳氮磷总量的相关性减弱,而溶解性养分间的相关性增强,形成了特殊的养分协同演化;水库群之间水力滞留时间的差异与水体碳氮磷浓度具有较好的线性关系...     

蒋家沟泥石流输沙年际变化及其灾变预测

根据云南东川蒋家沟泥石流年输沙量的时序资料,分析了蒋家沟泥石流输沙的年际变化特征,发现历年输沙量变动幅度大,波动明显且年际变化频繁,用灰色系统理论的灾变预测方法,建立泥石流年输沙量的等维新息灾变预测模型,能够对未来可能出现的灾变年份进行较好的预测。在前期研究基础上,补充最新观测资料,建立了新的灾变时间序列和相应的等维新息灾变预测模型,使蒋家沟泥石流的年输沙量灾变预测得以连续进行,并对预测结果进行了检验,效果较为理想。     

Deciphering fluid origins in the Paleozoic Laoshankou Fe-Cu-Au deposit,East Junggar: Constraints from noble gases and halogens

To constrain the ore-fluid source(s) of the Laoshankou Fe-Cu-Au deposit(Junggar orogen,NW China),we analyzed the fluid inclusion(FI) noble gas(Ar,Kr and Xe) and halogen(Cl,Brand Ⅰ) compositions in the hydrothermal epidote and quartz.Four hypogene alteration/mineralization stages,including(Ⅰ) pre-ore Ca-silicate,(Ⅱ)early-ore amphibole-epidote-magnetite,(Ⅲ) late-ore pyrite-chalcopyrite,and(Ⅳ) post-ore hydrothermal veining,have been identified at Laoshankou.Stage Ⅱ FIs have salinity of 15.7 wt.%(NaCl eq.), I/Cl molar ratios of75 × 10~(-6)-135 × 10~(-6), and Br/Cl molar ratios of 1.4 × 10~(-3)-2.1 × 10~(-3).The moderately-high seawatercorrected Br*/I ratios(0.5-1.5) and low ~(40)ArE/Cl slope(～10~(-5)) indicate the presence of sedimentary marine pore fluid,which was modified by seawater reacting with the Beitashan Fm.volcanic rocks.Stage Ⅲ fluid is more saline than their stage Ⅱ and Ⅳ counterparts,reaching up to 23.3 wt.%(NaCl+CaCl_2 eq.) close to halite saturation(～26 wt.%).The fluid has I/Cl ratios of 75 × 10~(-6)-90 × 10~(-6) and Br/Cl ratios of 1.5 × 10~(-3)-1.8 × 10~(-3).Considering the increasing ~(40)ArE/Cl trend toward bittern brine and the higher 36 Ar content than air-saturated water(ASW),a bittern fluid source is inferred from seawater evaporation,which was modified by interaction with organic-rich marine sedimentary rocks.Stage Ⅳ FIs have lower temperature(110-228 ℃) and Br/Cl(0.90 × 10~(-3)-1.2 × 10~(-3)),but higher 36 Ar content than ASW,indicative of dissolved evaporite or halite input.Considering also the low δD_(fluid)(-114‰ to-144‰) and δ~(18)O_(fluid)(2.1‰-3.5‰) values,meteoric water(with minor dissolved evaporites) likely dominated the stage Ⅳ fluid.The evaporites may have formed through continuous evaporation of the stage Ⅲ surface-derived bittern.Involvement of non-magmatic fluids and different ore-fluid origins in stage s Ⅱ and Ⅲ sugge st that the ore-forming proce ss was different from a typical magmatichydrothermal fluid-dominated skarn mineralization,which was previously proposed for Laoshankou.Our noble gas and halogen study at Laoshankou provide new insights on the fluid sources for the Paleozoic Fe-Cu(-Au)deposits in the Central Asian Orogenic Belt(CAOB),and our non-magmatic fluid source interpretation is consistent with the basin inversion setting for the mineralization.     

东准噶尔北缘老山口铁铜金矿床古生代岩浆岩锆石U-Pb年代学、氧逸度特征及地质意义

老山口矿床位于新疆东准噶尔北缘,是区域内重要的铁铜金矿床。矿区内岩浆岩发育广泛,对其中的奥陶纪玄武安山岩(约449 Ma),奥陶纪安山岩(约447 Ma),泥盆纪火山岩(393~376 Ma)、二长闪长岩(约379 Ma)、黑云母闪长岩(约379 Ma)、石英正长岩(约376 Ma)、细粒闪长岩(约370 Ma),石炭纪碱性花岗岩(约330 Ma)和粗粒闪长玢岩(约310 Ma)进行了成岩年代学的统计和测试,结果表明老山口矿床存在3期岩浆活动：450~440 Ma、约390~370 Ma以及330~310 Ma。结合区域构造演化可知,其中450~440 Ma和390~370 Ma的岩浆活动形成于不同时期俯冲相关的岛弧环境,而330~310 Ma的岩浆活动则形成于后碰撞板内伸展环境。根据铜金矿化的时代,可将矿区内的岩浆岩分为3期：成矿前、同成矿及成矿后。老山口同成矿期岩浆岩(泥盆纪火山岩、二长闪长岩、闪长玢岩和黑云母闪长岩)具有相对较高的(Eu/Eu*)N、(Ce/Ce*)N和CeⅣ/CeⅢ值,分别为0.13~0.86、1.14~445.92和33.34~1 165.04,说明铁铜金矿化与高氧逸度的岩浆活动有关。     

辽宁海城及其邻区地震活动性研究

由于受到台站分布不理想、速度结构研究不准确以及震相拾取误差等因素的影响,常规地震定位结果精度较低。因此,研究收集了辽宁省地震台网的地震目录及震相数据,采用双差地震定位方法,对海城及其附近地区（39°N-43°N,120°E-126°E）20 a的1 400多次地震进行重新定位。与原始定位结果相比,双差定位结果表明：1）震中更加呈条带状集中,尤其在40.5°N-41.0°N,122.0°E-123.0°E区间,与该地区的海城河-大洋河断裂带走向相一致;2）该地区地震多发生于地下5~20 km,与该区中地壳存在的低速高导层相对应;3）深度剖面图显示,大部分地震沿垂直向下柱状分布,原因是该处有粉碎性破裂带,从地下25 km处延伸到近地表。双差定位算法使得定位后均方根残差的平均值由0.74 s下降到0.26 s。辽宁地区的地震震级与发生地震数量有关,地震数量陡然增多,大地震发生概率增大。     

青藏高原东南缘活动断裂地质灾害效应研究现状

青藏高原东南缘不同性质、不同类型、不同特点活动断裂发育且较为活跃,自2008年汶川地震发生以来,相继发生了玉树地震、庐山地震、鲁甸地震等。地震引发、触发、诱发产生了大量地质灾害,造成了惨重的生命财产损失。通过收集与分析相关资料,对青藏高原东南缘活动断裂地质灾害效应研究进展与取得成果进行了归纳总结,从活动断裂地质灾害主要控制因素,地质灾害发育特征、空间分布规律、演化模式、形成机制,不同性质断裂控制效应、断裂两盘差异效应、地震动参数效应、地形地貌效应等地质环境效应和地质灾害力学效应等方面进行了综述。在此基础上,对活动断裂地质灾害效应研究中存在的如不同类型活动断裂和不同震级地震与地震地质灾害相关性、以及地震地质灾害监测与风险评估等问题或重点研究方向进行了探讨,其研究结果为地震地质灾害致灾机理、风险评估、防灾减灾等研究提供参考。