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Modern developments in image mining

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Science China(Technological Sciences) 2008年第S1期51卷 13-25页

作者： alfred stein ITC PO Box 6 7500 AA EnschedeNetherlands

This paper presents some new developments in image mining. Image mining con-siders the chain from object identification from remote sensing images through modeling,tracking on a series of images and prediction,towards communication to stakeholders. Attention is given to image mining for vague and uncertain objects. Aspects of up-and down-scaling are addressed. We further consider in this paper both spatial interpolation and decision making. The paper is illustrated with several case studies.

关键词： image mining uncertain objects spatial data quality decision making scale

Use of a multi-temporal grid method to analyze changes in glacier coverage in the Tibetan Plateau

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Progress in Natural Science:Materials International 2009年第7期19卷 861-872页

作者： alfred stein International Institute for Geo-Information Science and Earth Observation (ITC)

This paper describes a multi-temporal grid method for quantifying changes in glacier coverage. A multi-temporal grid synthesizes spatial, attribute and process components of glacier information by sequentially combining spatial data from satellite images or maps. It enables us to identify glacier retreat and advance areas in individual grid cells for three or more periods of data sets. Discrepancies among the sequential data sets were detected graphically and numerically, including noise from geo-location error, misclassification, or different interpretation results in various pixel resolutions. Noise was detected and corrected to a large extent by visualization of the synthetic grid. The paper compares the results with that from a common method based on individual data sets, focusing on the Mt. Naimona’Nyi and Mt. Qomolangma regions at the northern slopes of the Himalayas. Results show that the identified noise (e.g. by 2.5 km2 in the Mt. Naimona’Nyi region) is much larger than measurement uncertainty calculated by sensor resolution and coregistration error (e.g. by 0.015 km2 in the Mt. Naimona’Nyi region). After noise removal, we notice that glacier recession clearly accelerates. The multi-temporal grid method results in a better quantification of glacier variation. It shows that glaciers in the Himalayas have both retreated and advanced during the last several decades, with retreat dominating and accelerating. Glaciers on the northern slope of Mt. Qomolangma in the middle Himalayas retreat more extensively and faster than those in the Mt. Naimona’Nyi region in the western Himalayas.

关键词： Glacier Multi-temporal grid Mt. Naimona’Nyi Mt. Qomolangma Himalayas Tibetan Plateau

Monitoring Glacier and Supra-glacier Lakes from Space in Mt. Qomolangma Region of the Himalayas on the Tibetan Plateau in China

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Journal of Mountain Science 2009年第3期6卷 211-220页

作者： YE Qinghua ZHONG Zhenwei KANG Shichang alfred stein WEI Qiufang LIU Jingshi Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences (CAS) Beijing 100085 China State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China International Institutefor Geo-Information Science and Earth Observation (ITC) PO Box 67500 AA Enschede The Netherlands

Because of the large number and remoteness, satellite data, including microwave data and optical imagery, have commonly been used in alpine glaciers surveys. Using remote sensing and Geographical Information System （GIS） techniques, the paper presents the results of a multitemporal satellite glacier extent mapping and glacier changes by glacier sizes in the Mt. Qomolangma region at the northern slopes of the middle Himalayas over the Tibetan Plateau. Glaciers in this region have both retreated and advanced in the past 35 years, with retreat dominating. The glacier retreat area was 3.23 km2 （or o.75 km^2 yr^-1 during 1974 and 1976, 8.68 km^2 （or 0.36 km^2 yr^-1 during 1976 and 1992, 1.44 km^2 （or 0.12 km^2 yr^-1） during 1992-2ooo. 1.14 km^2 （or 0.22 km^2 yr^-1 during 2000-2003, and 0.52 km^2 （or 0.07 km^2 yr^-1 during 2003-2008, respectively. While supra-glacier lakes on the debris-terminus of the Rongbuk Glacier were enlarged dramatically at the same time, from 0.05 km^2 in 1974 increased to 0.71 km^2 in 2008, which was more than 13 times larger in the last 35 years. In addition, glacier changes also showed spatial differences, for example, glacier retreat rate was the fastest at glacier termini between 5400 and 5700 m a.s.l than at other elevations. The result also shows that glaciers in the middle Himalayas retreat almost at a same pace with those in the western Himalayas.

关键词： Glacier lake Remote Sensing Mr. Qomolangma region Himalayas Tibetan Plateau

LOW-IMPACT LAND DEVELOPMENT:THE PRACTICE OF PRESERVING NATURAL PROCESSES

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Journal of Green Building 2006年第4期1卷 28-38页

作者： R.alfred Vick Melissa Tufts School of Environmental Design

INTRODUCTION Land development is a human activity that has tremendous impacts on the structure and function of the *** impacts,more often than not,disrupt and degrade natural processes on the site and in adjacent or functionally connected *** Nature Conservancy has identified habitat degradation due to development as the greatest threat to biodiversity in the United States,partially responsible for the threatened status of 85%of the species that have been identified as such(stein 2000).In recent decades,development has affected more land than ever *** to the ***,the rate of conversion of land from undeveloped to developed is 2.65 times the rate of population growth in the U.S.,a signal of sprawling,land-consumptive *** only are more undeveloped sites,or greenfields,being impacted by development,but the impacts appear to be more severe than in previous eras.A recent article in Landscape Architecture Magazine titled“Why Suburbs Will Never Have Tall Trees:Modern Construction Methods Doom Trees Before They’ve Even Been Planted,”makes the observation that older neighborhoods throughout North America appear to provide a suitable environment for tree growth resulting in mature urban forests,while modern-era developments are frequently conspicuous due to the short-lived,stunted,or diseased trees that struggle to survive on these sites(Kidd 2006).

关键词： neighborhood landscape habitat

Distribution and Sources of Organic Matter in Surface Sediments of the Northern Bering and Chukchi Seas by Using Bulk and Tetraether Proxies

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Journal of Ocean University of China 2019年第3期18卷 563-572页

作者： JI Zhongqiang JIN Haiyan stein Ruediger LI Zhongqiao BAI Youcheng LI Hongliang ZHANG Yang CHEN Jianfang Key Laboratory of Marine Ecosystem and Biogeochemistry State Oceanic Administration Second Institute of Oceanography Ministry of Natural Resources Hangzhou 310012 China State Key Laboratory of Satellite Ocean Environment Dynamics Hangzhou 310012 China alfred Wegener Institute Helmholtz Center for Polar and Marine Research Bremerhaven 27568 Germany

The organic matter (OM) preserved in Arctic Ocean sediments is of great importance to the global carbon budget. How-ever, works that apply multiple proxies to determine the distribution and concentration of organic carbon (OC) in the surface sedi-ments of the northern Bering and Chukchi Seas remain limited. Here a multiproxy approach based on bulk OM parameters and the branched vs. isoprenoid tetraether (BIT) index was used to investigate the distribution and sources of OM in the surface sediments of the northern Bering and Chukchi Seas. Binary and ternary mixing models were applied to trace the contribution of different OC sources to the total OC in the study area. The δ13C values of the sediments provided by the binary model showed that the proportion of terrestrial OC fell in the range of 27.4%–79.8% (46.2% on average). The BIT index returned the lowest fraction (4.8%–27.3%, 12.0% on average). The ternary mixing model was employed to determine the plant-, soil-, and marine-derived fractions of the total OM. The ternary model showed that 11.5%±6.3%, 31.4%±9.5%, and 57.1%±12.4% of OM in the sediment of the study area was derived from soil, plants, and marine sources, respectively. The differences in OM composition between the west and east sides of the Chukchi Sea were controlled by OM inputs from key water masses (i.e., Anadyr Water and Alaska Coastal Water), river discharge, and the nutrient supply from the Pacific inflow that supports marine productivity.

关键词： northern Bering Sea Chukchi Sea organic matter GDGTs bulk parameters

Species-specific,pan-European diameter increment models based on data of 2.3 million trees

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Forest Ecosystems 2018年第3期5卷 277-295页

作者： Mart-Jan Schelhaas Geerten M Hengeveld Nanny Heidema Esther Thurig Brigitte Rohner Giorgio Vacchiano Jordi Vayreda John Redmond Jaroslaw Socha Jonas Fridman stein Tomter Heino Polley Susana Barreiro Gert-Jan Nabuurs Wageningen University and Research Wageningen Environmental Research(WENR)Droevendaalsesteeg 36708PB WageningenThe Netherlands Wageningen University and Research BiometrisDroevendaalsesteeg 16708PB WageningenThe Netherlands Wageningen University and Research Forest and Nature Conservation Policy GroupDroevendaalsesteeg 36708PB WageningenThe Netherlands Swiss Federal Institute for Forest Snow and Landscape Research WSLResource AnalysisZuercherstrasse 111CH-8903 BirmensdorfSwitzerland European Commission Joint Research CentreDirectorate DSustainable Resources-Bio-Economy UnitIspraItaly CREAF 08193 Cerdanyola del VallesSpain Univ Autonoma Barcelona 08193 Cerdanyola del VallesSpain Forest Service Department of AgricultureFood and the MarineJohnstown Castle EstateCo.WexfordIreland Department of Biometry and Forest Productivity Institute of Forest Resources ManagementFaculty of ForestryUniversity of Agriculture in KrakowAI.29Listopada 4631-425CracowPoland Swedish University of Agricultural Sciences (SLU) 90183 UmeaSweden Norwegian Institute of Bioeconomy Research P.O.Box 115N-143 1AsNorway Thunen Institute Institute of Forest EcosystemsAlfred-Mo1ler-Strabe 1Haus41/4216225 EberswaldeGermany Forest Research Centre (CEF) Instituto Superior de AgronomiaUniversidade de LisboaTapada da Ajuda1349-017Lisbon.Portugal Wageningen University and Research Forest Ecology and Forest Management GroupDroevendaalsesteeg 36708PBWageningenThe Netherlands

Background: Over the last decades, many forest simulators have been developed for the forests of individual European countries. The underlying growth models are usually based on national datasets of varying size, obtained from National Forest Inventories or from long-term research plots. Many of these models include country-and location-specific predictors, such as site quality indices that may aggregate climate, soil properties and topography effects. Consequently, it is not sensible to compare such models among countries, and it is often impossible to apply models outside the region or country they were developed for. However, there is a clear need for more generically applicable but still locally accurate and climate sensitive simulators at the European scale, which requires the development of models that are applicable across the European continent. The purpose of this study is to develop tree diameter increment models that are applicable at the European scale, but still locally accurate. We compiled and used a dataset of diameter increment observations of over 2.3 million trees from 10 National Forest Inventories in Europe and a set of 99 potential explanatory variables covering forest structure, weather, climate, soil and nutrient ***: Diameter increment models are presented for 20 species/species groups. Selection of explanatory variables was done using a combination of forward and backward selection methods. The explained variance ranged from10% to 53% depending on the species. Variables related to forest structure(basal area of the stand and relative size of the tree) contributed most to the explained variance, but environmental variables were important to account for spatial patterns. The type of environmental variables included differed greatly among ***: The presented diameter increment models are the first of their kind that are applicable at the European scale. This is an important step towards the development of a new ge

关键词： European forests Diameter increment model Climate change Growth modelling National forest inventory