基于ERDAS的SPOT5卫星影像正射校正方法研究

海岛海岸带卫星遥感调查与评价项目以高分辨率卫星遥感影像数据为基础。项目区块地形有一半为山地和丘陵,地形起伏较大,常规的几何校正难以消除因地形起伏引起的影像几何变形,必须进行正射校正。根据现有数据特点和项目要求,提出了可行的正射校正流程,基于SPOT5物理模型对融合影像进行正射校正,实验校正结果完全满足精度要求。     

基于NDVI城镇土地利用变化检测探讨

通过归一化植被指数（NDVI）结合影像差值,对经过辐射校正后的1993年和2005年武汉地区TM影像进行了土地利用变化检测,与监督法分类进行比较,得出NDVI更宜于实现变化信息探测和提取。     

第二次土地调查与详查之比较

由于技术条件和执行的环境不同,第一次土地调查与第二次土地调查之间存在很大的差异。从重视程度、调查的方法与内容、调查底图和存储方式以及调查人员的专业程度等四个方面分析了两次土地调查的区别。     

浅谈基于不同时期多源影像的数据更新

主要阐述了卫星遥感数据的几何纠正及融合技术,对实际生产具有指导意义.     

湿地水文过程与植被响应研究进展与案例分析

生态水文学是20世纪90年代兴起的一门研究生态过程和生态格局水文机制的新学科。湖泊湿地作为中国5大类天然湿地类型之一,湖泊湿地生态水文学的研究业已成为生态水文学的研究的一个重要对象和分支,其核心在于研究湖泊湿地生态系统中多时空尺度的水文与生物格局、过程的耦合特征及其相互作用。论文首先概述了湖泊湿地生态水文学的研究进展,包括其基本理论,内涵、外延及其主要研究内容;凝练了湖泊湿地生态水文学研究的方法体系、思路及框架;针对目前湖泊湿地生态水文学研究中存在的问题及薄弱环节,提出了湖泊湿地生态水文学未来研究的发展趋势和亟需加强研究的重点方向。在此基础上,以长江中游的典型通江湖泊湿地——鄱阳湖湿地为例,通过开展的湖泊湿地生态水文过程与模拟研究的典型案例,阐述了鄱阳湖湖泊湿地生态水文过程的变化及其植被响应研究的最新进展和研究成果。论文对于构建涵盖湖泊湿地水资源、湖泊湿地生态景观格局与流域管理、湖泊湿地生物多样性保育以及湿地资源可持续利用与生态管理等方向在内的战略研究体系,完善湿地生态水文研究与流域生态与管理的技术支撑体系具有重要的指导意义和实践价值。     

基于傅里叶级数的中国沿海地区Tm模型精化研究

本文采用中国沿海地区13个探空站2010~2014年实测地表温度T_s与平均温度T_m数据,利用傅里叶级数分析法精化中国沿海地区T_m模型,并将2015年探空站实测T_m数据与精化模型进行对比检验。结果表明,精化模型在T_m探测方面具有更高的计算精度,其计算大气可降水量的误差概率分布趋近于正态分布,具有较强的稳定性。     

Supplementation of Yeast Extract to Practical Diet Improves the Growth,Anti-Oxidative Capacity and Intestinal Morphology of Shrimp Litopenaeus vannamei

Two control diets based on the commercial formula were designed to contain high(27%, D1) and low(22%, D2) levels of fish meal, respectively. Into D2, 500, 1000 and 1500 mg kg~(-1) of yeast extract were added, respectively, yielding three experimental diets(YE1 through YE3). Shrimp(initial body weight 0.30 g ± 0.02 g) were fed with the experimental diets, five tanks each diet and 30 shrimp individuals each tank, for 8 weeks, and then challenged with Vibrio parahaemolyticus. The results showed that the specific growth rate(SGR) of shrimp in D2 was significantly lower than that of shrimp in D1(P 0.05). The SGR of shrimp in YE3 was similar to that of shrimp in D1. The feed intake of shrimp was similar between D1 and D2. The feed conversion ratio and protein efficiency ratio of shrimp were similar among all diets(P 0.05). YE significantly improved the activity of glutathione S-transferase. The concentration of glutathione(GSH) and the total serum anti-oxidative capacity(T-AOC) of D1 were significantly higher than those of shrimp feeding other diets(P 0.05). The content of serum malondialdehyde of shrimp feeding YE2 and YE3 was significantly lower than that of shrimp feeding D2(P 0.05). The thickness of intestine muscular layer of shrimp feeding YE1 and YE2 was similar to that of shrimp feeding D1. The shrimp feeding YE1 showed the highest villus height of intestine among all groups. The cumulative mortality after challenging was similar among all groups(70.00%–86.67%)(P 0.05). In conclusion, 1000–1500 mg kg~(-1) of YE was suggested to be supplemented into the practical diets to improve the growth, anti-oxidative capacity and intestinal morphology of shrimp L. vannamei.     

Tidal Effects on the Bottom Thermal Front of North Yellow Sea Cold Water Mass near Zhangzi Island in Summer 2009

Three seabed-mounted TD/CTD chains and two upward-looking acoustic Doppler current profilers(ADCPs) in the southwest of Zhangzi Island are used and a simultaneous cruise observation in the northern North Yellow Sea(NYS) is conducted to study temperature variation in the bottom thermal front zone of the NYS Cold Water Mass(NYSCWM) during the summer of 2009. In the flood-ebb tidal cycles, the bottom temperature decreases(increases) during flood(ebb) tides, which are dominated by the tidal-current induced horizontal advection. The ebb tide-induced temperature increase is larger than the flood tide-induced temperature decrease due to seasonal warming. In the spring-neap tidal cycles, the temperature and the vertical temperature structure show notable fortnightly variation from 16 July to 25 August. The bottom temperature increases from neap to spring tides and decreases from spring to neap. The Richardson number demonstrates strengthened vertical mixing during spring tides but enhanced stratification during neap tides. The spring-neap variation in vertical shear caused by tidal current is the dominant factor that induces the fortnightly variation in vertical mixing and thus bottom temperature.     

中国耕地土壤相对湿度时空分异

以全国653个农业气象站1993-2013年耕地的土壤相对湿度数据为基础,运用地统计方法,分析中国耕地土壤相对湿度时空分异特征与规律。结果表明:自1993年以来全国耕地的土壤相对湿度呈现波动上升趋势。全国耕地的土壤相对湿度普遍大于60%,分布区域自4月中旬开始随夏季风推移不断向北向西扩大,自10月下旬开始向东、南方向缩小。耕地土壤相对湿度值随土壤深度的增加而增加。年际尺度上,耕地的土壤相对湿度在夏秋季上升速度最快,变化幅度随土层深度增加而变小。土壤相对湿度与降水量存在较强的正相关关系,与潜在蒸发量、气温普遍存在较强的负相关关系。土壤相对湿度与各气象要素的相关性随深度加深而减弱。春、夏、秋季气象因素对旱地土壤相对湿度影响较大,冬季气象因素对水田影响更大。     

Effect of diet on the development,survival, and reproduction of the calanoid copepod Pseudodiaptomus dubia

Pseudodiapto,mus dubia is a calanoid copepod abundant in the mariculture ponds of southern China.However,our understanding of the population dynamics of P.dubia in aquaculture ponds is limited.In this study,groups of larval P.dubia were each fed a different microalgal species,and the effects of these different diets on development,survival,and reproduction were assessed.The five microalgae used were species common in aquaculture farms in China,and included two chlorophytes(Chlorella saccharophila and Platymonas subcordiformis),one golden microalga(Isochrysis zhan.jiangensis),and two diatoms(Chaetoceros muelleri and Cyclotella meneghinia,na).Our results indicated that C.saccharophila was not a suitable food for larval P.dubia,as all larvae fed this microalga died at stage Ⅲ(as copepodites).The survival rates of P.dubia larvae fed C.muelleri,Ⅰ. zhanjiangensis,and P.subcordiformis were significantly higher than that of larvae fed C.meneghiniana.In the adult stage,copepods fed C.muelleri,I. zhanjiangensis,and C.meneghiniana produced more nauplii(430-566 nauplii/female),had higher intrinsic growth rates(0.2-0.253/d),and better longevity(59-60 days)than those fed P.subcordiformis.Our results therefore suggest that P.dubia has different nutritional needs and food preferences at different life stages.For example,P.subcordifonnis was suitable for developing larvae but not for breeding adults,while C.meneghiniana was suitable for breeding adults but not for developing larvae.Both C.muelleri and I.zhanjiangensis were excellent foods for P.dubia throughout the entire life cycle.