东海区鲯鳅的后期仔鱼、幼鱼分布和产卵习性的初步报告

鲯鳅Coryphaena hippurus Linnaeus是暖水性的上层鱼类,广泛分布于世界各处外海和洋区,内湾和内海较少见.在太平洋广泛分布于热带、亚热带海区.     

Some problems on dynamical sedimentology in sea area near Huanghe Seaport

In this paper, two problems on dynamical sedimentology in the sea area near the Huanghe(Yellow) River Seaport are studied. Firstly, with synchronously observed data of bed-load trap and winds, starting and transporting dynamical mechanism of sediments on the intertidal shoal is analysed and studied. It is considered that starting and diffusing of sediments on the intertidal shoal near the Huanghe Seaport are controlled by waves and their surf currents. Secondly, with the help of data observed through observation concentration of suspended sediments, current velocity and wave height, starting and diffusing dynamical mechanism of sediments on the seabed near the Huanghe Seaport are analysed. It is considered that at a water depth of about 15 metres, starting and diffusing of the sediments are mainly controlled by tidal currents and at 5 metres or on the intertidal shoal by waves. At about 10 metres, their effects are rather similar.     

El Nino and anti-El Nino events in 1854-1987

-Using the COADS data set of sea surface temperature in the Equatorial Eastern Pacific, thirty one El Nino events and twenty four anti -El Nino events were identified for the period from 1854 to 1987. The results were compared with those of the other authors. The El Nino events (or anti -El Nino events ) are classified into two groups according to the timing of occrrence of the events: one starts at the first half of a year, another begins at the second half of a year. Both 1982-1983 and 1986-1987 events fall into the second group, which are characterized by the eastward migration of the positive anomaly of the sea surface temperature and the significant increasing of the anomaly in September or October.     

Spatial and temporal variation of the urban impervious surface and its driving forces in the central city of Harbin

Associated with the rapid economic development of China, the level of urbanization is becoming a serious concern. Harbin, the capital city of Heilongjiang Province, China and one of the political, economic, cultural, and transportation centers of the northeastern region of China, has experienced rapid urbanization recently. To examine the spatial patterns of long-term urbanization and explore its driving forces, we employed the impervious surface fraction derived from remote sensing image as a primary indicator. Specifically, urban impervious surface information for the central city of Harbin in 1984, 1993, 2002, and 2010 was extracted from Landsat Thematic Mapper image using a Linear Spectral Mixture Analysis (LMSA). Then, the spatial and temporal variation characteristics and the driving factors of percent impervious surface area (ISA) changes were analyzed throughout this 26-year period (1984 to 2010). Analysis of results suggests that: (1) ISAs in the central city of Harbin constantly increased, particularly from 1993 to 2010, a rapid urbanization period; (2) the gravity center of impervious surface area in the central city was located in Nangang District in 1984, moving southeast from 1984 to 1993, northwest from 1993 to 2002, and continuing toward the southeast from 2002 to 2010; and (3) the urban growth of the central city can be characterized as edge-type growth.     

Unraveling enhanced membrane lipid biosynthesis in Chlamydomonas reinhardtii starchless mutant sta6 by using an electrospray ionization mass spectrometry-based lipidomics method

The unicellular green alga Chlamydomonas reinhardtii, a well-established model organism, has been widely used in dissecting glycerolipid metabolism in oxygenating photosynthetic organisms. In previous studies, it has been found that shunting carbon precursors from the starch synthesis pathway can lead to a 10-fold increase in TAG content as compared to the wild type, but it is unknown whether inactivation of AGPase may affect membrane lipids biosynthesis. The study aims to investigate global changes in lipid metabolism and homeostasis in the starchless mutant C. reinhardtii sta6. By utilizing an electrospray ionization/mass spectrometry (ESI/MS)-based lipidomics approach, a total of 105 membrane lipid molecules of C. reinhardtii were resolved, including 16 monogalactosyldiacylglycerol (MGDG), 16 digalactosyldiacylglycerol (DGDG), 11 phosphatidylglycerol (PG), 6 sulfoquinovosyldiacylglycerol (SQDG), 49 diacylglyceryl-N,N,N-trimethylhomoserine (DGTS), 2 phosphatidylethanolamine (PE), and 5 phosphatidylinositol (PI) molecules. The quantitative results indicated that the membrane lipid profiles were similar between the two C. reinhardtii strains grown under both low- and high-light conditions, but the cellular contents of a great number of lipids were altered in sta6 due to the defect in starch biosynthesis. Under low-light conditions, sta6 accumulated more PI, MGDG, DGDG but less amounts of DGTS as compared to WT. Under high light, sta6 cells contained higher content membrane lipids than cc-124, except for PG, which is more or less similar in both strains. Our results demonstrate that the cellular membrane lipid homeostasis underwent profound changes in the starchless mutant, and thereby its physiological impact remains to be explored.     

Challenge of vegetation greening on water resources sustainability: Insights from a modeling‐based analysis in Northwest China

Forest restoration policies are often implemented without the assessment of their full environmental impact. In this study, we investigated the challenges of vegetation greening resulted from forest restoration on water resource sustainability, using a model‐based simulation in northwestern China. Four different vegetation scenarios and 25 future climate scenarios were employed using the Soil and Water Assessment Tool model. Results suggest that (a) the mean annual evapotranspiration changes from only 7.2% in the barren case to 100% in the forest case; however, it produced a 35.2% reduction in average annual streamflow and a 157% increase in soil water storage. The upstream vegetation greening caused the enhancement of water retention, while also creating great challenges for future downstream water resource sustainability; (b) seasonal effect was significant in that 100% forest case increased evapotranspiration (+40%) but it also reduced the streamflow (?73%) compared to the barren case in growing season, which may exacerbate spring and summer drought; (c) changes of evapotranspiration and streamflow were only 0.3% and ?0.9% at T + 3.9 °C when compared to the historic scenario in barren cases, while for all forest cases, variations were 3% and ?21.8%, respectively; (d) vegetation greening induced more remarkable changes in hydrological components than those resulting from climate change. Our “what if” research provides new insights for promoting sustainable management of water resources and ecosystems in mountainous water source areas.     

基于遗传神经网络的克钦湖叶绿素反演研究

叶绿素a浓度能够在一定程度上反映内陆湖泊水质情况。为实现对克钦湖水体叶绿素a浓度的监测,于2010年8月15日对克钦湖进行了现场光谱测量和同步采样。通过分析叶绿素a浓度和光谱数据之间的关系,建立基于反射比、人工神经网络和遗传神经网络的叶绿素a浓度估测模型。结果表明:利用R700nm/R670nm反射比建立的模型估测精度为R2=0.67;人工神经网络模型的估测精度较高,R2=0.882;将遗传算法引入神经网络之后,模型的估测精度进一步提高,R2达到0.956,将模型预测的结果与克里格内插法相结合对研究区的叶绿素a空间分布情况进行定量估测,发现北湖的叶绿素a浓度明显高于南湖,有由北向南逐渐递减的趋势,这为今后利用高光谱数据对克钦湖叶绿素a浓度大面积遥感反演提供了研究基础。     

Study on runoff simulation of the upstream of Minjiang River under future climate change scenarios

Climate change is one of the main factors that affect runoff changes. In the upstream of Minjiang River, the temperature increased significantly in the last 50 years, while the precipitation decreased on the contrary. In order to analyze the effect of climate change on site runoff, watershed runoff depth and evaporation, nine climate scenarios are assumed based on rainfall and temperature indicators. A SWAT model of Minjiang River is constructed, and runoff simulation is carried out with the nine scenarios. The results show that if precipitation increases or decreases 20 %, the change rate of runoff depth will increase or decrease 28–32 %; if temperature increases or decreases 2 °C, the change rate of runoff depth will decrease or increase 1–6 %; if temperature increases or decreases 2 °C, the change rate of the potential evaporation will increase or decrease 5–16 %, and the actual evaporation rate of variation will increase or decrease 1–6 %. Overall, precipitation variation has greater effect on simulated runoff than temperature variation dose. In addition, temperature variation has more obvious effect on the runoff simulation results in dry years than in wet years. The actual evaporation of watershed depends on evaporation capacity and precipitation and increases with the increasing of the potential evaporation and precipitation. The study also shows that the climate change scenarios analysis technology, combined with SWAT hydrological model, can effectively simulate the effect of climate change on runoff.

     

昌宁—孟连缝合带乌木龙—铜厂街洋岛型火山岩地球化学特征及其大地构造意义

详细的地球化学解析表明,乌木龙—铜厂街地区出露的蛇绿混杂岩主要包括方辉橄榄岩、纯橄榄岩和碱性玄武岩。其中,方辉橄榄岩和纯橄榄岩具有极低的CaO含量(<0.1%)、稀土总量(<5×10-6)和(La/Yb)N(0.96～1.14)值,(Ce/Yb)N为1.04～1.37,为轻稀土弱亏损型。本区碱性玄武岩具有高TiO2(2.57%～3.33%)、高K2O(2.29%～5.52%)的显著特征,(La/Yb)N为15.42～19.81,(Ce/Yb)N为12.48～14.76,为轻稀土强烈富集型;岩石Ti/V、Th/Ta、Th/Yb、Ti/Yb、Ta/Yb与来自亏损地幔的MORB以及与俯冲有关的岛弧火山岩明显不同,而主要显示为OIB型火山岩的微量元素地球化学特征,乃是典型的大洋板块内部岩浆作用的产物。该区洋岛型火山岩的厘定,表明昌宁—孟连古洋盆在石炭—二叠纪期间曾经历过一个由初始洋盆到成熟洋盆的完整发育演化过程。