Antarctica: measuring glacier velocity from satellite images

Many Landsat images of Antarctica show distinctive flow and crevasse features in the floating part of ice streams and outlet glaciers immediately below their grounding zones. Some of the features, which move with the glacier or ice stream, remain visible over many years and thus allow time-lapse measurements of ice velocities. Measurements taken from Landsat images of features on Byrd Glacier agree well with detailed ground and aerial observations. The satellite-image technique thus offers a rapid and cost-effective method of obtaining average velocities, to a first order of accuracy, of many ice streams and outlet glaciers near their termini.     

Prediction of kiwifruit orchard characteristics from satellite images

Precision Agriculture - The dry matter content of New Zealand kiwifruit is currently measured using destructive testing of a 90-fruit sample. Dry matter content varies from 14 to 20% with a...     

Deforestation history of the eastern rain forests of madagascar from satellite images

Madagascar is biologically one of the richest areas on Earth, and its plants and animals are among the most endangered. Satellite images and vegetation maps based on earlier aerial photographs were used to determine the extent of eastern rain forests in Madagascar and to monitor the rate of deforestation over a 35-year period. In 1985, 3.8 million hectares of rain forest remained, representing only 50 percent of the 7.6 million hectares existing in 1950 and 34 percent of the estimated orignal extent (11.2 million hectares). Between 1950 and 1985, the rate of deforestation averaged 111,000 hectares per year. Deforestation was most rapid in areas with low topographic relief and high population density. If cutting of forests continues at the same pace, only forests on the steepest slopes will survive the next 35 years.     

Temporal variability of the antarctic circumpolar current observed from satellite altimetry

Sea level measurements by the Seasat altimeter were used to study the temporal variability of the Antarctic Circumpolar Current between July and October 1978. Large-scale zonal coherence in the cross-stream sea level difference was observed, indicating a general increase in the surface geostrophic velocity of the current around the Southern Ocean. The result demonstrates the power of satellite altimetry to monitor the variability of large-scale ocean currents.     

Remote sensing of surface ocean circulation with satellite altimetry

The Geodynamics Experimental Ocean Satellite (GEOS-3) radar altimeter has provided some information on the dynamic sea-surface topography of the global oceans. Regional studies of the densely surveyed Sargasso Sea indicate that the average nontidal variability of the oceans is +/- 28 centimeters. Sea-surface highs and lows determined from GEOS-3 altimetry correlate favorably with eddy structures inferred from Nimbus-6 infrared imagery.     

Analytical models integrated with satellite images for optimized pest management

The global field protection (GFP) was developed to protect and optimize pest management resources integrating satellite images for precise field demarcation with physical models of controlled release devices of pesticides to protect large fields. The GFP was implemented using a graphical user interface to aid the end-user to select location and define an arbitrary perimeter for protection. The system provides coordinates of drop points for the controlled release devices which can be delivered using drone technology, e.g. unmanned air vehicles. In this work, we present the first proof of concept of this technology. A vast number of pest management applications can benefit from this work, including prevention against vector-borne diseases as well as protection of large agriculture fields.     

国产高分系列遥感卫星影像的批量自动配准研究

【目的 】遥感影像的精确几何配准对于国产高分系列卫星影像处理以及后续的农情监测等应用至关重要。【方法 】文章基于自动配准和正射校正程序包AROP,选择16 m分辨率的高分1号、高分6号宽幅影像和3 m分辨率高分2号、高分7号多光谱影像作为实验数据,以经过几何精校正的10 m分辨率的Sentinel-2影像和3 m分辨率的谷歌影像为基准影像,在农业用地场景和城市用地场景下,进行批量的几何配准实验,对配准的结果进行目视检验和定量评价。同时,为了更好地匹配高分影像与Sentinel-2影像,将高分1号、高分6号宽幅数据重采样到15 m的分辨率进行几何配准。【结果 】在农业用地和城市用地场景下,配准精度大多达到了0.5个像元以内,满足了影像配准的精度标准。其中15 m分辨率的高分1号和高分6号的配准精度分别为0.31～0.54和0.33～0.53,均小于0.6个像元;3 m分辨率的高分2号的配准精度在0.47～0.6之间,小于0.6个像元;高分7号的配准精度在0.44～0.49之间,小于0.5个像元,而且所有高分系列遥感卫星在配准后均目视效果出色,接边良好。【结论 】利用AROP对15 m分辨...     

Long waves in the eastern equatorial pacific ocean: a view from a geostationary satellite

During 1975, westward-moving long waves with a period of about 25 days and a wavelength of 1000 kilometers were observed at a sea surface temperature front in the equatorial Pacific on infrared images obtained by a geostationary environmental satellite system. The absence of these waves during 1976, and the above-average equatorial sea surface temperatures during 1976, may be related to a decrease in the southeasterly trade winds during that year.     

Suitability of satellite remote sensing data for yield estimation in northeast Germany

Precision Agriculture - Information provided by satellite data is becoming increasingly important in the field of agriculture. Estimating biomass, nitrogen content or crop yield can improve farm...     

Automated interpretation of protective forest plantings on high-resolution satellite images

An important problem in forestry interpretation of satellite images is the identification of areas with a different species composition. Visual interpretation is presently supported by means of computer technologies. The article presents the results of determining the reliability of automated interpretation of pure protective forest plantings on high-resolution satellite images in ENVI software.     

An assessment of multi-view spectral information from UAV-based color-infrared images for improved estimation of nitrogen nutrition status in winter wheat

Precision Agriculture - Rapid, accurate and non-destructive assessment of nutrition status is beneficial not only to the optimization of fertilization strategy in crop production, but also to the...     

区域棉稻轮作周期的遥感估算和统计分析方法

评估大地理区域内作物轮作水平是农业生产中必须解决的重要问题之一.借助统计学分析方法,在解译连续两年作物卫星遥感影像的基础上,构建统计分析模型,计算农作物的统计轮作周期、评估农作物统计轮作水平.对江苏省兴化市初步研究表明,该市棉稻轮作周期为2.09年,与传统的轮作周期相比较,统计轮作周期和水平更能反映大地理区域作物轮作的现状.     

应用高分辨率卫星数据估算阔叶红松林乔木多样性

应用遥感技术估算生物多样性是森林生态学的研究热点和难点。为探索高分辨率卫星数据在估算森林植被多样性上的应用潜力,以吉林蛟河市阔叶红松林大样地数据为支撑,提取了红松树冠的空间分布格局,并估算了乔木物种多样性。首先,基于冬季GeoEye-1影像提取红松树冠分布图,与样地每木调查数据吻合较好。然后,使用景观生态学和地统计学指数,分析红松种群空间分布规律,发现了最大自相关尺度30~40 m。最后,选择拥有红边波段的秋季RapidEye卫星图像,建立遥感影像5 m光谱值和30 m窗口大小纹理参数与生物多样性指数的多元线性回归模型。结果表明,红边信息并未显著改善多光谱数据估算植被生物多样性的能力,但所获大区域制图结果与林分龄级吻合较好。      

基于计算机视觉的鸡蛋表面积估算方法

鸡蛋表面积参数已广泛应用于蛋品加工业以及生物学的研究上,但其传统手工检测方法存在着效率低的缺点.基于计算机视觉技术,提出了一种像素面积投影法来计算三维目标的表面积,该方法简单易于实现,且对任意不规则目标表面积的估算都适用.以3种特殊曲面的表面积为例,验证了该估算方法的精确度.通过对鸡蛋建立旋转椭球数学模型采用像素面积投影法进行了计算,并与实验数据对比,二者相对误差小于10%,满足实际工程需求.     

基于叶片图像多特征融合的观叶植物种类识别

叶片图像特征提取对于植物自动分类识别有着重要的研究意义。本文以观叶植物叶片为研究对象,综合提取叶片图像的颜色、形状和纹理特征,基于支持向量机(SVM)原理提出了基于图像分析的观叶植物自动识别分类方法。通过对50种观叶植物样本图像进行训练和识别,与BP神经网络和KNN识别方法进行比较,本文所采用的SVM分类器的识别率能够达到91.41%,取得了较好的识别效果。      

基本农田变化信息在不同空间分辨率卫星影像中的提取方法研究

本文介绍了不同分辨率影像中基本农田变化信息的提取方法,重点介绍了中低分辨率影像中基于光谱知识的信息自动提取方法．以岳池县花园镇为例,采用的影像是2001年的TN和2006年SPOT2进行对比分析、识别、运算,然后提取。经分析得出不同空间分辨率影像中变化信息采用不同的方法进行提取,并对两种方法进行比较,可为今后的基本农田遥感动态监测提供更简单快捷的方法。     

基于四旋翼无人机快速获取大田植株图像的方法及其应用

利用低空无人机获取农田信息,具有实时以及灵活性高、成本低等优势。为快速、精确监测大田规模化种植作物的生长发育状况,以四旋翼无人机为平台,结合数字图像技术,建立快速获取大田烟株中前期图像的方法。结果表明,在天空辐射条件较稳定的条件下,采用较低的飞行高度(如20m)航拍获取田块图像,能够得到清晰的拼接图像和三维重建效果;采用基于决策树的植被分割算法将烟草和非植被部分分割后,得到较高精度的大田植株图像。在此基础上进行大田烟草缺苗数估测,所估算的缺苗数与实测值吻合较好。     

基于高分辨率卫星影像的基本农田监测研究——以郫县古城镇为例

采用高分辨率卫星影像结合基本农田数据库对基本农田变化进行实时监测,在较短的时间内能够准确、及时的获取基本农田的面积变化和变化流向信息,为基本农田保护提供有力决策依据。     

利用二维数字图像估算种猪体重

为解决生产过程中种猪体重称量困难,难以对其生长进行实时监测的问题,提出利用二维数字图像对种猪体重进行估算的方法。利用数码摄像机获取种猪样本图像,采用域值分割法对图像进行分割,根据投影区域与参考系的比例关系估算得到种猪真实投影面积和体高,并建立了其与体重的回归方程。实验结果表明:用该方程估算得到的种猪体重与实际称量体重的平均相对误差为3.2%,精度较高,验证了本方法估算种猪体重的可行性。本方法可以避免传统称量方法可能导致的猪的应激反应给生产带来的损失,降低种猪生产成本,可用于种猪生长过程的监测和研究,为种猪的现代化饲养管理提供了一种有效的监测手段。