Ecological effects of co-culturing sea cucumber Apostichopus japonicus (Selenka) with scallop Chlamys farreri in earthen ponds

Monthly changes in sedimentation and sediment properties were studied for three different culture treatments: sea cucumber monoculture (Mc), sea cucumber and scallop polyculture (Ps-c) and scallop monoculture (Ms). Results indicated that the survival rate of sea cucumber was significantly higher in Ps-c cultures than in Mc cultures. Sea cucumber yield was 69.6% higher in Ps-c culture than in Mc culture. No significant differences in body weight and scallop shell length were found between Ps-c and Ms cultures. The mean sedimentation rate of total particulate matter (TPM) was 72.2 g/(m2 d) in Ps-c cultures, with a maximum of 119.7 g/(m2 d), which was markedly higher than that of Mc (mean value). Sedimentation rates of organic matter (OM), total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) in Ps-c cultures were also significantly higher than those in Mc cultures. TOC and TN contents of sediment increased rapidly in the first 5 months in Ms cultures and remained at a high level. TOC and TN contents in Mc and Ps-c cultures decreased during sea cucumber feeding seasons and increased during sea cucumber dormancy periods (summer and winter). The study demonstrates that co-culture of sea cucumber and scallop in earthen ponds is an alternative way to alleviate nutrient loads and improve water quality in coastal aquaculture systems. Moreover, it provides the additional benefit of an increased sea cucumber yield.     

Community characteristics of wild fruit forests along elevation gradients and the relationships between the wild fruit forests and environments in the Keguqin Mountain region of Iii

In this paper,the quantitative relationship between the wild fruit communities and direct environmental factors is discussed on the basis of detailed data on landscape scale habitats obtained through field vegetation investigation.The results from TWINSPAN and DCCA showed that:1) In the distribution sections of the wild fruit forest in the Keguqin Mountain region,the basic patterns characteristic of the different habitats are due to topographic factors,nutrients and moisture conditions;2) The elevation affected the most basic differentiation of plant communities in the study area,indicating that the elevation condition was the most important factor restricting the distribution of the wild fruit communities in the study area;3) The close relationship between the moisture content in the upper soil layer and the elevation reflected the influence of moisture conditions on both wild fruit and herb-layer communities;4) Nutrient differences not only indicated that the habitat conditions were different in themselves but also showed that the present nutrient conditions of the habitats were seriously affected by human activities.In summary,under complicated mountainous topographic conditions,the habitat conditions for the communities differed very significantly,and the combination of elevation,soil moisture content,total nitrogen,slope aspect,and pH value influenced and controlled the formation of community distribution patterns in the study area.     

区域旅游发展的生态安全系统分析——-以内蒙古自治区四子王旗为例

旅游发展有时会给目的地带来负面影响, 为了诊断其整体发展水平, 采用“压力―状态―响应”框架模型, 以内蒙古自治区四子王旗为例, 来分析区域旅游生态系统的安全状态。从旅游生态环境压力、旅游生态环境质量和 旅游生态环境保护整治及建设能力3 个方面来考虑, 根据层次分析法原理及各评价指标间的相互关系, 构建层次 结构模型, 和23 个指标。经过对评价指标不安全指数值的计算和标准值的确定以及指标权重值的确定, 再利用各 指标的不安全度公式和总体生态系统不安全度公式计算出旅游生态系统处于较不安全状态, 并讨论了甄别各因子 对生态系统的限制程度的方法, 对区域旅游发展的生态系统安全分析具有现实意义。     

松辽盆地徐家围子断陷深层异常高孔带分布特征与成因分析

为了解松辽盆地低孔低渗背景下优质储集层的形成和分布,文中应用岩心实测孔隙度、测井孔隙 度以及铸体薄片等资料,研究了松辽盆地徐家围子断陷异常高孔带的分布特征及其成因。结果表明,松辽盆地 北部纵向上发育3个异常高孔带（ⅰ-ⅲ）, 其深度分布范围分别为600~2350m、2500~3500m、3600~4400m,对应的孔隙度分别为12%~35%,6%~28%,5%~20%。第ⅰ高孔带主要发育在中浅层, 主要由Ⅰ、 Ⅱ型干酪根形成的有机酸溶蚀砂岩储集层形成;第ⅱ、ⅲ异常高孔带发育在深层,主要由Ⅲ型干酪根产生的大 量有机酸溶蚀砂砾岩储集层和火山岩储集层形成,大气水淋滤作用也有一定贡献。此外,裂缝和岩相对徐家围 子断陷深层异常高孔带的形成具有特别重要的意义。     

北京地震台宽频带面波震级公式建立

利用IASPEI推荐的宽频震级计算公式MBB,重新量取并计算北京地震台1993—2003年(数字宽频地震记录系统与模拟地震仪器记录并行时期)的MBB、MSK、MKIRNOS震级,并分别同中国地震台网中心发布震级MCENC进行震级偏差比较。对比结果显示:采用宽频带垂直向速度型面波震级的MBB,震级偏差在震中距0°—180°范围内均呈现良好的稳定性,且与中国地震台网中心发布的震级偏差最小。遂利用最小二乘法,采用IASPEI公布的宽频带面波震级计算框架,拟合出北京地震台宽频震级公式。     

地质雷达在活动断裂研究中的应用

对于快速发生沉积和侵蚀的地区,断裂附近的古地震遗迹会很快被掩埋。获取这些地区断裂的位置、上断点的埋深和标志层的断距等方面的数据至关重要。本文利用地质雷达探测技术探测这些被埋藏的古地震遗迹。以北京平原区正断性质的新夏垫断裂和青藏高原东北缘六盘山地区逆冲性质的六盘山东麓断裂为实验区。通过探测发现,对于断裂两侧地表覆盖层主要为粉土或粉质粘土的新夏垫断裂,地质雷达可精确定位断裂通过的位置,指示上断点的埋深,但无法在地质雷达剖面上识别出各套地层。对于在T1基座阶地上通过的六盘山东麓断裂,地质雷达不但可以精确定位断裂的位置,而且可以在地质雷达剖面上识别出各套地层,进而求得断裂两侧基座的断距。     

New records of Jurassic petrified wood in Jianchang of western Liaoning,China and their palaeoclimate implications

Diverse and rich fossil wood records have been documented from the Mesozoic of Liaoning Province, NE China. The Tiaojishan Formation(mainly distributed in Beipiao, Chaoyang, Fuxin and Jianchang regions) is one of the most significant horizons for the Jurassic petrified wood in Liaoning Province. Previously, wood fossils of this formation were mainly reported in Beipiao and Chaoyang regions, whereas fossil wood record was merely known in Jianchang region. Here we describe new fossil wood specimens from the Tiaojishan Formation in Jianchang County, western Liaoning. Two fossil wood taxa, i.e., Protaxodioxylon jianchangense Tian et Wang sp. nov. and Xenoxylon peidense Zheng et Zhang were recognized on the basis of anatomical features. These fossil wood records add new data for understanding the fossil wood diversity, floral composition and palaeoclimate of the Tiaojishan Formation. The occurrence of Xenoxylon and Protaxodioxylon implies a cool temperate, wet and seasonal climate condition with interannual variations during the Middle to Late Jurassic transition in western Liaoning region.     

The structural characteristics,age of origin,and tectonic attribute of the Erguna Fault,NE China

The Erguna Fault runs along the east bank of the Erguna River in NE China and is a large-scale ductile shear zone comprising granitic mylonites. This paper reports on the geometry, kinematic indicators, and 40Ar/39 Ar biotite ages of the granitic mylonites, to constrain the structural characteristics, forming age, and tectonic attribute of the Erguna ductile shear zone. The zone strikes NE and records a top-to-the-NW sense of shear. A mylonitic foliation and stretching lineation are well developed in the mylonites, which are classified as S-L tectonites. Logarithmic flinn parameters(1.18–2.35) indicate elongate strain which approximates to plane strain. Kinematic vorticity numbers are 0.42–0.92 and 0.48–0.94, based on the polar Mohr diagram and the oblique foliation in quartz ribbons, respectively, suggesting that the ductile shear zone formed under general shear, or a combination of simple and pure shear. According to finite strain and kinematic vorticity analyses, the Erguna Fault is a lengthening-thinning ductile shear zone that formed by extension. The deformation behavior of minerals in the mylonites indicates that the fault was the site of three stages of deformation: an initial stage of middle- to deep-level, high-temperature shear, a post-stress recovery phase of high-temperature static recrystallization, and a final phase of low-temperature uplift and cooling. The 40Ar/39 Ar plateau ages of biotite from the granitic mylonites are 106.16 ± 0.79 and 111.55 ± 0.67 Ma, which constrain the timing of low-temperature uplift and cooling but are younger than the ages of metamorphic core complexes(MCCs) in the Transbaikalia-northeast Mongolia region. Using measured geological sections, microtectonics, estimates of finite strain and kinematic vorticity, and regional correlations and geochronology, we conclude that the Erguna Fault is an Early Cretaceous, NNE-trending, large-scale, sub-horizontal, and extensional ductile shear zone. It shares a similar tectonic background with the MCCs, volcanic fault basins, and large and super-large volcanic-hydrothermal deposits in Transbaikalia-northeast Mongolia and the western Great Khingan Mountains, all of which are the result of overthickened crust that gravitationally collapsed and extended in the Early Cretaceous after plate collision along the present-day Sino-Russia-Mongolia border tract.     

上海市学生人群防震减灾科普工作现状调查研究——以初中生群体为例

为了全面系统评价上海市学生人群的防震减灾科普效果,准确了解其科普需求,课题组在2014年下半年选取上海市某初级中学的部分学生作为示例,从科普知识的认知程度、需求与认知偏好、对宣传工作满意度评价、科普教育在学校开展的情况这四个方面进行问卷调查,以便及时总结经验,为今后在该人群中更加科学、高效地开展防震减灾科普宣传工作打下坚实的基础。     

新疆萨尔托海糜棱岩化石英菱镁岩元素地球化学特征及其对金成矿作用的贡献

新疆萨尔托海石英菱镁岩产在达拉布特蛇绿混杂岩带中,是蛇纹岩在剪切带深部发生热液交代作用的产物。蛇纹岩先转变为滑石片岩,再进一步转变为石英菱镁岩。石英菱镁岩局部发生剪切变形,形成糜棱岩化石英菱镁岩。与蛇纹岩相比,石英菱镁岩的MgO和SiO_2含量降低,Al_2O_3和CaO含量升高;而糜棱岩化石英菱镁岩的MgO含量较石英菱镁岩降低,Al_2O_3和SiO_2含量较石英菱镁岩升高。微量元素地球化学对比研究表明石英菱镁岩继承了蛇纹岩的微量元素特征;而糜棱岩化石英菱镁岩的微量元素含量较蛇纹岩发生了显著变化,稀土元素、高场强元素和自然金的含量明显升高,指示这些元素在剪切变形过程中发生迁移富集。剪切变形伴随强烈的流体/岩石反应,并导致剪切带流体组成和物理化学性质发生改变,从而影响矿物结晶或分解,并控制微量元素的带入迁出。蛇纹岩转变为石英菱镁岩的过程释放Au,可为糜棱岩化石英菱镁岩中的金矿化提供成矿元素。