Energy flow in Branchiura sowerbyi (Oligochaeta: tubificidae) in a shallow macrophyte-dominated lake, Biandantang Lake     

Yan Yunjun  Liang Yanling 《中国海洋湖沼学报》2004,22(4):403-407

The energy flow ofBranchiura sowerbyi was studied for the first time in China in a shallow macrophytic lake, Biandantang Lake, Hubei Province. The energy flow was calculated from the measurement of flesh production (12.5241kJ/m²a), egestion (517.7302kJ/m²a), metabolism (38.3273 kJ/m²a), and excretion (4.3798kJ/m²a). The net growth efficiency of the species is about 22.7%, which accords well with the generally reported value for oligochaetes. In addition, the relationship between starvation respiration (R, mgO₂/ind·d), wet weight (Ww, mg) and temperature (T, °C) were also measured, with the regression function beingR=0.008Ww^0.736 e^0.050T. Project supported by NSFC (30270278, 3960019), the foundation of the government of Hubei Province (No. 2000J109), and the foundation of Ecological Station, CAS in the Institute of Hydrobiology.  相似文献   

再创找矿佳绩,为我省经济建设立新功——对我省找矿突破的几点看法     

叶允钧 《福建地质》2008,27(2):125-129

分析了福建省铁、铜、铅锌、钼、金、银、锡、非金属、能源等矿产的成矿地质条件、资源背景、找矿潜力、重点成矿区带、部分含矿层、岩浆-构造-成矿作用等,对我省地质找矿突破的方向提出了看法和建议。  相似文献   

圆形截面灌注桩正截面均匀配筋计算可视化     

杨超  罗运军  张英才 《岩土工程技术》2004,18(6):299-302

在圆形截面均匀配筋偏心受压混凝土构件的正截面承载力基本计算公式的基础之上 ,结合基坑工程中圆截面灌注桩的受力特点 ,推导了灌注桩均匀配筋计算的有关公式 ,并以此为基础 ,利用可视化编程软件Delphi 6 .0编写了相应的配筋计算程序。通过实际例证 ,表明该程序计算快捷且结果准确。  相似文献   

全球气候数据集生成及气候变化应用研究     

梁顺林  唐世浩  张杰  徐冰  程洁  程晓  宫鹏  贾坤  江波  李爱农  刘素红  邱红  肖志强  谢先红  杨军  杨俊刚  姚云军  于贵瑞  张晓通  赵祥 《遥感学报》2016,20(6):1491-1499

科技部在"十三五"期间部署的国家重点研发计划"全球变化及应对"专项资助了"全球气候数据集生成及气候变化关键过程和要素监测"研究项目。项目围绕由全球气候观测系统提出的基本气候变量,完善地空天基观测体系,生成中国首套以遥感数据为主体的涵盖大气、海洋和陆表长时间序列、高精度、高时空一致性的产品,即气候数据集,动态监测全球变化关键过程和要素。  相似文献   

Using landscape indicators and Analytic Hierarchy Process (AHP) to determine the optimum spatial scale of urban land use patterns in Wuhan,China     

Qiuping Huang  Jiejun Huang  Yunjun Zhan  Wei Cui  Yanbin Yuan 《Earth Science Informatics》2018,11(4):567-578

Quantifying land use patterns and functions is critical for modeling urban ecological processes, and an emerging challenge is to apply models at multiple spatial scales. Methods of determining the optimum scale of land use patterns are commonly considered using landscape metrics. Landscape metrics are quantitative indicators for analyzing landscape heterogeneity at the landscape level. In this study, due to their widespread use in urban landscape analyses and well-documented effectiveness in quantifying landscape patterns, landscape metrics that represent dominance, shape, fragmentation and connectivity were selected. Five metrics include Patch Density, Contagion, Landscape Shape Index, Aggregation Index and Connectivity. Despite a wide application of landscape metrics for land use studies, the majority mainly focuses on the qualitative analysis of the characteristics of landscape metrics. The previous models are limited in exploring the optimum scale of land use patterns for their lack of quantitation. Therefore, taking the City of Wuhan as an example, the land use unit was treated as a patch, and the landscape pattern metrics at different spatial scales were calculated and compared so as to find the optimum one. Furthermore, a mathematical model of landscape metrics was proposed to quantify the scale effect of urban land use patterns, generating a complementary tool to select the optimum scale. In addition, Analytic Hierarchy Process (AHP) was introduced to determine the respective weights of the chosen landscape metrics in this model. Fractal dimension was ultimately applied to verify the chosen optimum scale of our study region. The results indicated that 60 m is confirmed to be the optimum scale for capturing the spatial variability of land use patterns in this study area.  相似文献   

Effect of wool fiber addition on the reinforcement of loose sands by microbially induced carbonate precipitation (MICP): mechanical property and underlying mechanism     

Yao  Dunfan  Wu  Jiao  Wang  Guowei  Wang  Pengbo  Zheng  Jun-Jie  Yan  Jinyong  Xu  Li  Yan  Yunjun 《Acta Geotechnica》2021,16(5):1401-1416

Acta Geotechnica - Animal fibers with α-keratin had obvious advantages of mechanical strength and durability on reinforced microbially induced carbonate precipitation (MICP)-cemented loose...  相似文献   

福建省东部火山岩地区银矿成矿地质条件及找矿方向     

朱熙道  叶允钧 《福建地质》1994,13(2):83-98

通过对该区银矿床地质特征、成矿地质条件和成矿规律的研究，将区内银矿按成因、成矿作用、矿床地质特征等划分为三类六型。指出了火山－次火山热液型银矿是本区银矿的重要类型。总结了银矿的找矿标志，提出了本区银矿的主攻类型和主攻地区。  相似文献   

立体影视与地景仿真   总被引：3，自引：0，他引：3  

夏运钧 《测绘学院学报》1996,(1)

在进行“虚拟现实”、ＧＩＳ等各项研究中，立体观察当是最关键的技术之一。人为什么能看出立体？如何产生人工立体视觉？怎样在ＣＲＴ视屏上显示一个立体的图像？显然是大家十分关心的问题。本文包括如下两方面的内容：１）双眼自然立体视觉的生理基础。彩色立体电视与ＣＲＴ视屏立体观察的原理。重点介绍目前已广为采用的时分制视屏立体观察的原理。２）视屏立体观察用于地景仿真的初步实践。介绍如何以数字地面模型（ＤＴＭ）数据为原始资料，用３ＤＳ生成某一地区动态地面立体透视图，实现所谓视景地形仿真。  相似文献   

数据驱动的蒸散发遥感反演方法及产品研究进展     

刘萌  唐荣林  李召良  高懋芳  姚云军 《遥感学报》2021,25(8):1517-1537

蒸散发是水圈、大气圈和生物圈中水分循环和能量交换的纽带。在全球尺度上,蒸散发约占陆地降水总量的60%;作为其能量表达形式,潜热通量约占地表净辐射的80%。随着通量观测技术的发展,全球长期持续的观测数据得以获取和共享,近年来基于数据驱动的蒸散发遥感反演方法取得了较好的研究进展。本文针对数据驱动的蒸散发遥感反演方法和产品,从经验回归、机器学习和数据融合3个方面展开,对现有的研究进展进行了梳理、归纳和总结,并从驱动数据、反演方法、已有产品等方面指出目前仍存在的问题和不足。未来仍需开展数据驱动的高时空分辨率的蒸散发遥感反演方法的研究,有效考虑地表温度和土壤水分等可以指示地表蒸散发短期变化的重要信息,同时加强基于过程驱动的物理模型与数据驱动的模型的结合,使两类模型能互为补充、各自发挥所长,共同推动蒸散发遥感反演研究水平的进步。  相似文献   

基于时间序列雷达干涉测量的钱塘江海塘形变分析     

张云俊  万紫  谢酬  邵芸  袁名欢  陈武  王新 《遥感学报》2015,19(2):339-354

形变监测是海塘安全运行的重要组成部分。本文利用杭州地区2006年—2010年获取的31景EnvisatASAR影像,根据MTInSAR(Multi-Temporal In SAR)方法,综合提取PS(Persistent Scatterer)和DS(Distributed Scatterer)点,得到密集的钱塘江海塘形变的In SAR测量结果。与28个点的水准数据对比表明,两者的平均误差为0.436 mm,最大误差为5.016 mm,验证了In SAR技术毫米级的测量精度和准确性。通过这两种数据的时间序列分析发现,海塘的沉降在空间上具有连续性,其空间分布呈现为单峰下沉曲线;在时间上,则具有明显的线性变化规律,并伴随有短时间范围的小幅度波动。  相似文献