Papers to appear in forthcoming issues     

《Applied Geochemistry》1998,13(1):I

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内蒙古鄂尔多斯地区早白垩世新的翼龙类化石     

姬书安  张笠夫 《地学前缘》2020,27(6):365-370

发现于内蒙古鄂托克旗召稍早白垩世罗汉洞组的一件不完整翼龙类下颌标本,以下颌愈合部长且平直、齿骨侧嵴发育、近圆形齿窝沿侧嵴之上的齿骨侧面上半部分自前向后呈直线排列、齿窝直径(2~2.5 mm)前后变化较小、相邻齿窝的间距约为齿窝直径的一半、下颌牙齿密度为3枚/cm等特征,可归入梳颌翼龙科(Ctenochasmatidae),且代表一新属种——郝氏鄂托克翼龙Otogopterus haoae gen.et sp.nov.。该化石是继鄂托克旗新召准噶尔翼龙科的平颌鄂尔多斯翼龙Ordosipterus planignathus之后在内蒙古鄂尔多斯地区发现的第2件确切翼龙类材料,丰富了这一地区早白垩世脊椎动物群的组成。该翼龙也是继甘肃庆阳环河翼龙Huanhepterus quingyangensis之后在鄂尔多斯盆地发现的第2种梳颌翼龙科化石,进一步扩大了鄂尔多斯盆地梳颌翼龙科的地理分布范围,同时表明鄂尔多斯盆地是继辽宁西部之后梳颌翼龙科在中国的又一重要分布区。  相似文献   

苏鲁超高压变质带北缘古-新元古代浅变质基性岩的构造属性及其意义   总被引：1，自引：1，他引：0  

宋明春  周建波  林少一  李杰  李世勇  宋英昕  王斌  刘鹏瑞 《岩石学报》2020,36(2):315-332

苏鲁超高压变质带北缘发育的少量以浅变质基性杂岩为代表的非超高压变质岩片,为深入探讨造山带的大陆深俯冲作用及板块缝合线位置提供了重要的制约。1∶5万区域填图表明,浅变质基性杂岩分布于从家屯、胡家和海眼口等地,它们以石门-薛家庄韧性剪切带与超高压变质带分界。同位素测年结果指示,胡家斜长角闪岩时代为古元古代末(1790±27Ma、1853±15Ma),而从家屯斜长角闪岩时代为新元古代(797±11Ma、782±16Ma)。地球化学分析表明,从家屯和胡家斜长角闪岩的SiO_2、TiO_2、Fe_2OT_3和MgO含量分别为47. 20%～52. 60%、0. 98%～3. 30%、9. 31%～16. 78%和3. 76%～7. 13%,为拉斑玄武岩成分。岩石的稀土总量介于45. 8×10~(-6)～289. 0×10~(-6)之间,LREE/HREE=1. 29～11. 6,(La/Yb)_N=0. 45～17. 3,稀土配分曲线较平坦,无铕异常(δEu=0. 75～1. 37)。微量元素相对富集Ba、Rb和Sr,亏损Zr、Hf、Th和Nb。从家屯斜长角闪岩的地球化学特征与E型洋中脊玄武岩相似,而胡家斜长角闪岩则具有洋岛玄武岩特点。综合分析认为,从家屯和胡家斜长角闪岩分别与扬子板块和华北板块具有构造亲缘性,在三叠纪扬子板块向华北板块俯冲碰撞过程中,这些不同大地构造位置和性质的基性岩被刮削叠置于板块缝合线附近,构成了大陆板块俯冲的加积杂岩。同时认为,分布在超高压变质带与非超高压变质岩片之间的石门-薛家庄韧性剪切带为一条重要的板块缝合线。  相似文献   

基于MEMS加速度计空投浮标的波浪测量方法试验研究     

刘宁  魏晓辉  王斌  董涛 《海洋科学》2020,44(9):146-153

针对基于MEMS加速度传感器的空投波浪浮标存在采样频率与测波精度低的问题,根据频域衰减积分算法,提出一种相应的波浪测量算法,为了验证该算法测波的准确性,开展了多功能水槽试验研究。该算法旨在将MEMS加速度传感器输出的加速度与姿态角转化为浮标运动的波形,首先将加速度与姿态角信号进行竖向处理获得竖直方向的加速度,再利用离散傅里叶变换将竖向加速度转化为频域内的加速度复数序列,然后引入控制函数减弱低频噪声,经过频域积分、离散傅里叶逆变换、时域积分获得竖直方向的位移,最后通过后处理得到最终的波形。多功能水槽试验采取10中不同波高和周期的工况,对比空投波浪测量浮标与波高仪的测量结果,试验结果表明,浮标的测量误差在10%以内,达到测波标准。  相似文献   

Assessment and prioritization of soil erosion triggering factors using analytical hierarchy process and Taguchi method   总被引：1，自引：0，他引：1  

Mehdi Hayatzadeh  Vahid Moosavi  Ramyar Aliramaee 《国际泥沙研究》2023,38(3):396-404

The main aims of this study are assessing some factors which affect the soil erosion process and evaluating the results of an analytical hierarchy process(AHP) method using the Taguchi method. Firstly, the weights for those factors and levels affecting soil erosion were determined by the AHP method. The determination of weights was based on the opinions of academic researchers, experts, middle managers,and members of the Soil and Water Research Centers in Iran. Secondly, an L32 Taguchi orthogona...  相似文献   

广西防城金花茶国家级自然保护区建立对区域土地利用动态的影响     

黄秋霞  廖南燕  杨元征  俎佳星  王嘉丽  蔡文华  杨健  苏宏新  杨婷 《热带地理》2022,42(6):973-984

以金花茶国家级自然保护区及保护区外2 km邻近区为研究区,选取1986―2019年7期Landsat遥感影像进行土地利用遥感解译,并基于GIS与R语言空间统计方法分析近35年土地利用动态演变规律。结果表明：1）保护区土地利用以林地为主,邻近区林地和耕地面积占比最大。2）邻近区综合土地利用动态度变化比非核心区更剧烈;二者土地利用程度综合指数变化均呈现升高－降低－不变的波动趋势,表明保护区建立后人为干扰的下降有助于土地利用格局的稳定。3）土地利用类型转换频率为邻近区向非核心区递减,表明保护区的建设与管理可以有效保护当地的生态环境。4）保护区非核心区所有土地利用类型重心总体上向东北方向迁移;邻近区建设用地与耕地重心总体上都为向西方向迁移,表明已有建设用地扩张对保护区周围的土地利用空间动态变化有重要影响。5）保护区的管理取得较为显著的成效,保护区内部生态环境得到改善,但内部建设用地的缓慢增加与资源的不合理生产开发,仍然对保护区的生境质量产生负面影响。  相似文献   

Surface complexation modeling for sulfate adsorption on ferrihydrite consistent with in situ infrared spectroscopic observations     

《Applied Geochemistry》2013

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Constructing logbook-like statistics for coastal fisheries using coastal surveillance radar and fish market data     

《Marine Policy》2014

As catch and effort statistics including fishing time and location are essential for producing abundance indices for utilized fish stocks, fishing states are encouraged under the FAO Code of Conduct for Responsible Fisheries to collect and maintain such statistics. However, for coastal fisheries (including artisanal fisheries) that are mainly composed of small-sized vessels which are usually too numerous to monitor, fisheries statistics collection systems are often either lacking or of insufficient quality (e.g. incomplete or inaccurate). Vessel monitoring system (VMS) data are commonly used to construct or improve estimation of fishing effort and fishing location in large-scale fisheries. Most coastal fisheries lack VMS but their countries do have coastal surveillance radar systems (CSRS) for security and enforcement purposes. This study illustrates and recommends opportunistic use of CSRS data to provide similar scientific benefits to VMS data for coastal fisheries. CSRS in combination with market landings data can construct logbook-like catch and effort statistics. This study introduces a method and demonstrates its usefulness for scientific research and management purposes, including the potential to obtain a higher accuracy and precision, particularly for fishing location and catch amount. Limitations of the CSRS data and challenges to managers involved in its application are also discussed.  相似文献   

Progress and Prospects in Tourism Research on Agricultural Heritage Sites     

TIAN Mi  MIN Qingwen  TAO Hui  YUAN Zheng  HE Lu  LUN Fei 《资源与生态学报(英文版)》2014,5(4):381-389

Agricultural heritage is an important type of world heritage. The special features of this kind of heritage are that they are "living" or "real life" systems, in both the ecosystem and in the cultural sense. So, agricultural heritage needs to be conserved in a special way. In a well-reasoned approach to dynamic conservation of agricultural heritage, careful development of heritage sites can realize greater sustainability of the traditional agriculture by considering both conservation and development though tourism. This paper examines the Global Important Agricultural Heritage Systems (GIAHS) as designated by the Food and Agriculture Organization of the United Nations (FAO) and listed by United Nations Educational, Scientific and Cultural Organization (UNESCO) as agricultural heritages sites. Currently, the research in China focuses on tourism resources evaluation and development, production design and marketing, tourism perception and the impacts of tourism development and so forth. There is less emphasis on research about benefit sharing of heritage tourism evolution mechanisms, environmental impacts of agricultural heritage tourism and study methods which should be analyzed in-depth, so as to illuminate the theories and practices of development in a living landscape.  相似文献   

鄱阳湖南矶山湿地沉水植物活体的光合荧光特性     

简敏菲  汪斯琛  余厚平  李玲玉  简美锋  余冠军 《资源与生态学报(英文版)》2015,6(1):52-59

采用FluorCam便携式叶绿素荧光成像仪测定鄱阳湖南矶山国家级自然保护区白沙湖和常湖冬季沉水植物的光合荧光特性,包括QY-max（即Fv/Fm,PSⅡ的最大光量子产量）、ΦPSⅡ（PSⅡ实际量子效率）、qP（光化学淬灭系数）等参数及其相应的荧光成像;应用频度法统计估测沉水植物的频度,并测定水环境的营养水平。结果表明：白沙湖优势沉水植物黑藻（Hydrilla verticillata）和苦草（Vallisneria natans）的PSⅡ的最大量子产量分别为0.48-0.68和0.52-0.71,PSⅡ实际量子效率分别为0.32-0.58和0.20-0.46,表明白沙湖的黑藻和苦草具有相似的光合作用效率;而常湖优势沉水植物莕菜（Nymphoides peltatum）和苦草的PSⅡ最大光量子产量分别为0.66-0.77和0.19-0.68,PSⅡ实际量子效率分别为0.26-0.48和0.22-0.43,表明莕菜有较高的光合作用效率,容易形成优势物种。调查中发现,白沙湖黑藻的频度为90%,苦草为93.3%,小茨藻（Najas minor）为26.7%,眼子菜（Potamogeton franchetii）为10%;常湖中莕菜的频度为86.7%,苦草为16.7%,小茨藻为56.7%。白沙湖中沉水植物的频度值总体高于常湖,优势物种也存在差异性。综合分析白沙湖和常湖水体的营养水平、沉水植物多样性和光合荧光特性,结果表明：白沙湖的富营养化水平高于常湖,黑藻和苦草同为沉水植物中的优势种,光合活性相似;常湖中莕菜和苦草为优势种,但莕菜的光合活性显著高于苦草,这与湖泊水体透明度和南矶山湿地不同水体的富营养化差异及不同沉水植物的生态位有着密不可分的关系。  相似文献