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51.
北部湾灯光罩网渔场时空分布与海洋环境关系分析 *   总被引:1,自引:0,他引:1  
文章根据大型灯光罩网渔船调查数据和卫星遥感海面风场(Sea Surface Wind, SSW)、海表温度(Sea Surface Temperature, SST)和叶绿素a浓度(Chlorophyll a concentration, Chl a)资料, 基于广义线性模型(Generalized Linear Model, GLM)对北部湾渔业资源单位捕捞努力量渔获量(Catch Per Unit Effort, CPUE)进行标准化, 应用多元线性回归等方法, 对北部湾灯光罩网渔场的时空分布及其与海洋环境的关系进行了分析。结果表明, 北部湾灯光罩网渔场适宜SST为27~29℃, Chl a为0.5~1.5mg·m -3。较高资源量出现在10月份中上旬, 分布在18°—19°N及20°—21°N海域。北部湾灯光罩网渔场的时空分布与季风、19°N附近的暖水池和Chl a等环境因素有关。  相似文献   
52.
安秦  陈圣波 《地理空间信息》2019,17(4):71-74,I0003
农作物长势监测和产量预测对于国家制定相关粮食政策、农业发展等都具有重要的意义,如何获得高效、宏观、精确的估产方法一直是学者关注的重点问题。以吉林省德惠市的玉米作为研究对象,利用光能利用率模型对玉米进行产量估算的研究,并且使用空间数据插值方法中的反距离权重法获得了每月平均温度数据的格网数据。通过玉米的净初级生产力NPP的累计值以及玉米的收获指数来获得最终的玉米产量值,利用验证点实测产量值与估算值的相关性和相对误差进行精度验证,相关系数R^2为0.649 9,平均相对误差值为1.676%,证明基于光能利用率模型的玉米估产在研究区具有一定的可行性。  相似文献   
53.
DMSP/OLS夜间灯光数据的四川省GDP空间化分析   总被引:1,自引:0,他引:1  
针对DMSP/OLS夜间灯光数据模拟省级格网GDP问题,该文选取2000、2006以及2010年DMSP/OLS稳定夜间灯光数据、辐射定标夜间灯光数据和四川省第二、三产业社会经济GDP数据,运用相关性分析、对比分析以及回归分析的方法,模拟出四川省GDP空间化密度图并分析与高程之间的关系。结果表明:在省级范围内,GDP与辐射定标灯光数据的相关性明显高于与稳定灯光数据的相关性,且前者的灯光指数CNLI与GDP相关性最高;运用3年的辐射定标灯光数据模拟得到四川省GDP密度图与GDP统计数据的拟合精度均达到0.99以上;2000-2010年四川省GDP呈现由成都市向四周不断扩张的趋势并随高程变化显著,四川省GDP高值区主要集中在高程1 000m以下的成都平原及周边区域,西部高原和山地地区GDP值较低。  相似文献   
54.
The characteristics and distribution patterns of detrital minerals (0.063~0.125 mm) in marine sediments provide a significant indicator for the identification of the origin of sediment.The detrital mineral composition of 219 surface sediment samples was analysed to identify the distribution of sediments within the western Philippine Sea. The area can be divided into three mineral provinces: (I) province east of the Philippine Trench, the detrital minerals in this province are mainly composed of calcareous or siliceous organisms, with the addition of volcanogenic minerals from an adjacent island arc; (II) middle mineral province, clastic minerals including feldspar, quartz and colorless volcanic glass, sourced from seamounts with intermediate-acid volcanic rock, or erupting intermediate-acid volcano; (III) province west of the Palau—Kyūshū Ridge, the matter provenance within this province is complex; the small quantity of feldspar and quartz may be sourced from seamounts or erupting volcano with intermediate-acid composition, with a component of volcanic scoria sourced from a volcano erupting on the Palau—Kyūshū Ridge. it is suggested that, (1) Biogenic debris of the study area is closely related to water depth, with the amount of biogenic debris controlled by carbonate lysocline. (2) Volcaniclastic matter derived from the adjacent island arc can be entrained by oceanic currents and transported towards the abyssal basin over a short distance. The weathering products of volcanic rocks of the submarine plateau (e.g.,Benham Plateau) and adjacent ridges provide an important source of detrital sedimentation, and the influence scope of them is constrained by the intensity of submarine weathering. (3) Terrigenous sediments from the continent of Asia and the adjacent Philippine island arc have little influence on the sedimentation of this study area, and the felsic mineral component is probably sourced from volcanic seamounts of intermediate-acid composition.  相似文献   
55.
The day–night cycle is one of the strongest geophysical cycles modulating species' behavioral rhythms. However, in deep-water continental margins, where light intensity decreases over depth, interspecific competition may alter behavioral responses to day–night cycles. The burrowing decapod crustacean Nephrops norvegicus is a large-size predator in benthic communities, exerting despotic territorial behavior. In this study, we analysed how the effect of light intensity cycles on decapod behavioral rhythms is reduced as one moves from shelves to slopes. In the Western Mediterranean, the predatory behavior and interspecific competition for substrate use of Nephrops increases moving from the shelf (100–110 m) to the slope (400–430 m). Vector fitting and generalized additive models were used to assess the effect of light intensity and behavioral rhythms of N. norvegicus on the temporal variation of prey decapods co-occurring in trawl tow catches carried out on the shelf and the slope during October 1999 and June 2000. The combination of diel variations in light intensity and N. norvegicus abundance influences the activity rhythms of prey decapods in a depth- and seasonal-dependent manner. Light modulation is stronger on the shelf and weaker on the slope, where Nephrops population size is greater. Although present regression analysis does not necessarily imply a direct cause–effect relationship between rhythms of predators and prey, we suggest that Nephrops alters the temporal patterning in the behavior of its prey on the slope, where light intensity is reduced. This alteration is stronger in endobenthic species than in benthopelagic species; the former rely on bottom substrate for the expression of behavioral rhythms, experiencing stronger interspecific competitions with Nephrops at time of activity.  相似文献   
56.
The underwater light regime of a Mediterranean coastal lagoon (Albufera des Grau, Balearic Islands) was studied during four years in order to characterise the spatial and temporal variations in the light attenuation coefficient (K) and to assess the relative contribution of the different water components to total light attenuation.  相似文献   
57.
The variability and origin of the Coloured Dissolved Organic Matter (CDOM) were studied in the Belgian coastal and adjacent areas including offshore waters and the Scheldt estuary, through the parameters: absorption at 375 nm, aCDOM(375), and the slope of the absorption curve, S. aCDOM(375) varied between 0.20 and 1.31 m−1 and between 0.97 and 4.30 m−1 in the marine area and Scheldt estuary, respectively. S fluctuated between 0.0101 and 0.0203 nm−1 in the marine area and between 0.0167 and 0.0191 nm−1 in the Scheldt estuary. The comparative analysis of aCDOM(375) and S variations evidenced different origins of CDOM in the BCZ. The Scheldt estuarine waters showed decreasing aCDOM(375) values with increasing salinity but constant S value of ∼0.018 nm−1 suggesting a dominant terrestrial origin of CDOM. On the contrary, samples collected in the marine domain showed a narrow range of aCDOM(375) but highly variable S suggesting the additional presence of autochthonous sources of CDOM. This source was evidenced based on the sorting of the marine offshore data according to the stage of the phytoplankton bloom when they were collected. A clear distinction was made between CDOM released during the growth stage characterized by high S (∼0.017 nm−1) and low aCDOM(375) and the decay phase characterized by low S (∼0.013 nm−1) and high aCDOM(375). This observation was supported by CDOM measurements performed on pure phytoplankton cultures which showed increased CDOM release along the wax and wane of the bloom but decreasing S. We concluded that the high variability of the CDOM signature in offshore waters is explained by the local biological production and processing of CDOM.  相似文献   
58.
Over the past 20 years, significant progress has been made in virtual plant modeling corresponding to the rapid advances in information technology. Virtual plant research has broad applications in agronomy, forestry, ecology and remote sensing. As many biological processes are driven by light, it is the key for virtual plant to estimate the light absorbed by each organ. This paper presents the radiance equation suitable for calculating sun and sky light intercepted by plant organs based on the principles of the interaction between light and plant canopy firstly; analyzes the process principles of plant canopy primary lighting based on ray casting and projection secondly; describes the multiple scattering of plant lighting based on Monte Carlo ray tracing method and on the radiosity method thirdly; and confirms the research with 3D visualization based on Virtual Reality Modeling Language (VRML) finally. The research is the primary work of digital agriculture, and important for monitoring and estimating corn growth in Northeast China.  相似文献   
59.
为了探究藻胆蛋白与高等植物类囊体膜之间的光能传递规律,验证重组藻胆蛋白是否可以与高等植物类囊体膜之间的光能传递,本研究分别提取了重组藻红蛋白、重组藻蓝蛋白以及菠菜和韭菜的类囊体进行混合孵育,然后进行了全波长吸收光谱以及荧光光谱检测。结果显示:混合孵育时间为10~20 min有利于重组藻红蛋白和藻蓝蛋白与类囊体膜结合并进行光能传递,最适混合孵育时间随重组藻胆蛋白和类囊体的种类不同而稍有不同;重组藻红蛋白不能与菠菜或韭菜的类囊体膜直接发生光能传递,但是当体系中添加重组藻蓝蛋白的时候就可以;重组藻蓝蛋白可以与类囊体中的叶绿素a直接进行光能传递,使得叶绿素a的荧光发射峰值显著提升,当藻红蛋白和藻蓝蛋白的比例是1∶2时,光能传递效率较高。本研究为藻胆蛋白在构建新型光合系统中的应用提供实验依据。  相似文献   
60.
In this paper AlGaInP light emitting diodes with different types of electrodes: Au/Zn/Au-ITO Au/Ti-ITO Au/Ge/Ni-ITO and Au-ITO are fabricated. The photoelectricity properties of those LEDs are studied. The results show that the Au/Zn/Au electrode greatly improves the performance of LEDs compared with the other electrodes. Because the Au/Zn/Au electrode not only forms a good Ohmic contact with indium tin oxide (ITO), but also reduces the specific contact resistances between ITO and GaP, which are 1.273×10-6 Ω · cm2 and 1.743×10-3 Ω ·cm2 between Au/Zn/Au-ITO and ITO-GaP respectively. Furthermore, the textured Zn/Au-ITO/Zn electrode is designed to improve the performances of LEDs, reduce the forward-voltage of the LED from 1.93 to 1.88 V, and increase the luminous intensity of the LEDs from 126 to 134 mcd when driven at 20 mA.  相似文献   
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