Instantaneous areal population density of entire Atlantic cod and herring spawning groups and group size distribution relative to total spawning population

The wide‐area group behaviour of spawning Atlantic cod and herring is investigated. By a combination of Ocean Acoustic Waveguide Remote Sensing (OAWRS) and conventional sensing methods, first‐look images of the instantaneous population density are obtained of entire Atlantic cod spawning groups, stretching for tens of kilometres in the Nordic Seas. This structural information made it possible to quantify the spawning group size distribution of cod over a roughly 30‐year period from conventional line‐transect data acquired annually by vertical echo sounding in the Nordic Seas. The size distribution is found to be consistent with the log‐normal probability density often found in growth processes that depend on many independent parameters. Nordic Seas cod populations are found to distribute into many vast behavioural groups during spawning with relatively stable mean size despite larger variations in total annual population. When sustained at pre‐industrial levels, the total spawning population is found to greatly exceed the mean spawning group size. As an apparent consequence of this large differential, when the total population, or overall scale, declined to within a standard deviation of this mean cod spawning group quantum, or inner‐group‐behavioural scale, return to pre‐industrial levels required decades. Findings for Atlantic herring are similar, where summing the spawning group populations measured in a single instantaneous OAWRS image per day over the 8‐day peak spawning period enabled accurate enumeration of the entire Georges Bank herring spawning population to within 7% of the independent NOAA estimate for 2006. These results may be relevant to other oceanic fish.     

Simultaneous Estimations of Forest Parameters using Aerial Photograph Interpreted Data and the k Nearest Neighbour Method

Information about the state of the forest is of vital importance in forest management planning. To enable high-precision modelling, many forest planning systems demand input data at the single-tree level. The conventional strategy for collecting such data is a plot-wise field inventory. This is expensive and, thus, cost-efficient alternatives are of interest. During recent years, the focus has been on remote sensing techniques. The k nearest neighbour (kNN) estimation method is a way to assign plot-wise data to all stands in a forest area, using remotely sensed data in connection with a sparse sample of field reference plots. Plot-wise aerial photograph interpretations combined with information from a stand register were used in this study. Nearness to a reference plot was decided upon using a regression transform distance. Standing stem volume was estimated with a relative root mean square error (RMSE) equal to 20% at the stand level, while age could be estimated with a RMSE equal to 15%. A cost-efficient data-capturing strategy could be to assign plot data with the presented kNN method to some types of forest, while using traditional field inventories in other, more valuable, stands.     

Application of the Irrigation Land Environmental Evaluation Tool for flood irrigation management and evaluation of water use

Irrigated zones worldwide suffer from water deficits, making it necessary to analyze irrigation management and to study alternatives to maximize adequate partitioning and distribution of irrigation water. The objective of this study is to compare the water use efficiency before (2001) and after (2002–2008) implementation of a new irrigation management plan in an area operating with traditional methods.     

长江口悬浮泥沙的MODIS影像遥感监测研究

通过对遥感监测泥沙原理和MODIS传感器特征的分析,应用不同时间的MODIS影像进行长江口及其附近海域的悬浮泥沙监测。结果表明:(1)长江口及其附近海域悬浮泥沙含量较高,其中杭州湾悬浮泥沙浓度高于长江口;(2)长江口及其附近海域水体中的泥沙由再悬浮形成,且冬季泥沙浓度和范围均大于春季;(3)入海径流与海洋动力是影响河口沿岸及近海水域水体悬浮泥沙含量的主要因素,其中海洋动力的潮流和波浪是主导控制因素。     

中国农作物长势遥感监测研究综述

农作物长势监测的目的是为早期估产提供依据，同时为田间管理提供及时的信息。笔者总结了中国农作物长势监测的研究进展、研究方法，指出用于长势监测的遥感数据空间分辨率较低，常用的监测指标 具有局限性，监测精度有待提高。“3S”技术的集成发展，进一步实现一体化应用于该领域仍是今后的发展方向。随着农作物长势运行化监测系统的进一步完善，对田间管理的诊断需求会日益加剧，因此作物长势的诊断将成为今后的研究重点。     

遥感技术在森林资源清查中的应用问题探讨

结合遥感技术在我国森林资源调查中应用的实际情况,对如何在一类清查、二类调查中应用遥感及如何综合应用遥感的问题进行了讨论.     

Applications of RS, GPS and GIS to Forest Management in China

ForeSt is an jmPOhant. renewable resource which iscomPOrt Of all kinds of plantS. It has the charaCtersOf long grOWth P6riod and complex land distribution.So it has spotal rules of dynamic change. Forestcannot be subStituted by other resources in theeconomic conSbothen and environmentsl proteCtion.SO ti is imment tO eStablish a good pattern of forestresource management. In odder tO realize this goal,ffod the dynamic change Of forest resource must bemonitored and Predbe. then on this b…     

Multispectral and Microwave Remote Sensing Models to Survey Soil Moisture and Salinity

Soil moisture stress and salinity are considered as a major form of land degradation in rain‐fed agricultural regions. The study has been carried out for four distinct periods such as 2001, 2005, 2010, and 2015 that was selected according to the climatic variations that occurred more than a decade. The multispectral remote sensing‐based empirical models were employed on Enhanced Thematic Mapper Plus and Operational Land Imager imageries to estimate the rate of soil moisture stress and salinity from 2001–2015. The rate of soil moisture stress has been magnified to 143%, and salinity was increased by 70% particularly from 2005–2010 when the drought period occurred. The reliability of identifying the saline‐affected soils from the multispectral remote sensing models was significantly affected (R ² = 0.39) because of the extensive distribution of Nerium oleander plants and water logging state in the study region. The modified microwave water cloud model revealed the three‐layer information such as N. oleander , soil, and vegetation such that an imaginary part of the dielectric constant derived from simplified Hallikainen empirical model has got good correlation (R ² = 0.73) with ground electrical conductivity measurements. Copyright © 2016 John Wiley & Sons, Ltd.     

红树林资源调查的遥感图象处理方法研究

在2001年应用“3S”技术与地面调查相结合的方法进行了广西红树林资源调查。以SPOT-HRV和Landsat 7 ETM 数据为信息源，采用1：1万地图形和GPS定位数据进行SPOT图象的几何精校正，并采用精校正后的SPOT图象对ETM 图象进行精校正。通过训练区对图象进行拉伸增强，然后采用锐化HIS变换的方法将SPOT图象与ETM 图象进行复合，经真彩色合成后得到的图象具有地物轮廓清晰、色彩丰富、层次分明的特点，红树林与滩涂、海域的区别十分明显，为红树林分布位置和边界的准确定位奠定了坚实的基础。     

REMOTE SENEING APPLICATION IN COUNTY-LEVEL LAND CLASSIFICATION AND LAND EVALUATION IN ARID AND SEMI-ARID ZONES——SHENMU COUNTY,SHAANXI PROVINCE AS A CASE STUDY

<正> 1. Backgrounds Land classification and evaluation are necessary foundments for county-level deci-sions of land use planning and economic development. On the bases of physical conditions,the targets of land classification and land evaluation adhere to particular principles andmethodologies are to find out the quality, quantity and spatial distribution regularities of re-gional structure of land, and to obtain relevant information of land suitabilities and land