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uv-b effects on the nutritional chemistry of plants and the res.onses of a mammalian herbivore

OECOLOGIA 2008年第1期156卷 125-135页

作者： Thines, Nicole J. Shipley, Lisa A. bassman, John H. Slusser, James R. Gao, Wei Washington State Univ Dept Nat Resource Sci Pullman WA 99164 USA USDA UV B Monitoring & Res Program Colorado State Univ Nat Resource Ecol Lab Ft Collins CO 80523 USA

Stratospheric ozone depletion has caused ground-level ultraviolet-b (uv-b) radiation to rise in temperate latitudes of both hemispheres. because the effects of enhanced uv-b radiation on the nutrition of food consumed by mammalian herbivores.are unknown, we measured nutritional and chemical constituents of 18 forages and related changes to in vitro dry matter digestibility. We also measured intake and in vivo digestibility of Pacific willow (Salix lasiandra) and alfalfa (Medicago sativa L.) by blue duikers (Cephalophus monticola). Forages were irradiated for 3 months with ambient (1x) or supplemental (1.6x) uv-b radiation repres.nting a 15% ozone depletion for Pullman, Washington, USA. Enhanced uv-b radiation had minimal and inconsistent effects on the nutritional content, in vitro dry matter digestibility, and protein-binding capacity of forages. However, flavonoid compounds increased in seven of the 13 forbs and woody dicots that were evaluated. Flavonoids were found to decrease only in yarrow (Achillea millefolium). When offered simultaneously, blue duikers preferred 1x and 1.6x uv-b irradiated plants of alfalfa equally, but ate 26% less willow grown under 1.6x uv-b radiation. However, when fed to duikers in separate feeding experiments, total dry matter intake and in vivo digestibility of dry matter, fiber, protein, and apparent energy did not differ between alfalfa and willow grown under 1x and 1.6x uv-b radiation. We conclude that expected increases in uv-b radiation from ozone depletion would have minimal effects on intake and digestion of ruminant herbivores.

关键词： blue duikers digestion flavonoids secondary compounds uv-b

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2003 North American interagency intercomparison of ultraviolet spectroradiometers: scanning and spectrograph instruments

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JOURNAL OF APPLIED REMOTE SENSING 2008年第1期2卷

作者： Lantz, Kathleen Disterhoft, Patrick Slusser, James Gao, Wei berndt, Jerry bernhard, Germar bloms, Sarah booth, Rocky Ehramjian, James Harrison, Lee Janson, George Johnston, Paul Kiedron, Piotr McKenzie, Richard Kimlin, Michael Neale, Patrick O'Neill, Michael Quang, Vi V. Seckmeyer, Gunther Taylor, Thomas Wuttke, Sigrid Michalsky, Joseph Univ Colorado Cooperat Inst Res Environm Studies Boulder CO 80309 USA SUNY Albany Atmospher Sci Res Ctr Albany NY 12203 USA Biospher Inc San Diego CA 92110 USA Natl Inst Water & Atmospher Res Lauder New Zealand Colorado State Univ USDA UV B Monitoring & Res Program Ft Collins CO 80523 USA NOAA Earth Syst Res Lab Boulder CO 80303 USA Univ Georgia Natl Ultraviolet Monitoring Ctr Athens GA 30602 USA Smithsonian Environm Res Ctr Edgewater MD 21037 USA Leibniz Univ Hannover Inst Meteorol & Climatol D-30419 Hannover Germany Queensland Univ Technol Australian Sun & Hlth Res Brisbane Qld 4001 Australia

The fifth North American Intercomparison of Ultraviolet monitoring Spectroradiometers was held June 13 to 21, 2003 at Table Mountain outside of boulder, Colorado, USA. The main purpose of the Intercomparison was to assess the ability of spectroradiometers to accurately measure solar ultraviolet irradiance, and to compare the res.lts between instruments of different monitoring networks. This Intercomparison was coordinated by NOAA and included participants from six national and international agencies. The uv measuring instruments included scanning spectroradiometers, spectrographs, and multi-filter radiometers. Synchronized spectral scans of the solar irradiance were performed between June 16 and 20, 2003. The spectral res.onsivities were determined for each instrument using the participants' lamps and calibration procedures.and with NOAA/CUCF standard lamps. This paper covers the scanning spectroradiometers and the one spectrograph. The solar irradiance measurements from the different instruments were deconvolved using a high res.lution extraterres.rial solar irradiance and reconvolved with a 1-nm triangular band-pass to account for differences in the bandwidths of the instruments. The measured solar irradiance from the spectroradiometers using the rivmSHIC algorithm on a clear-sky day on DOY 172 at 17.0 UTC (SZA = 30 degrees) had a relative 1-sigma standard deviation of +/-2.6 to 3.4% for 300- to 360-nm using the participants' calibration.

关键词： spectroradiometer filter radiometer ultraviolet intercomparison

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An operational retrieval algorithm for determining aerosol optical properties in the ultraviolet

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JOURNAL OF GEOPHYSICAL res.ARCH-ATMOSPHEres 2008年第D3期113卷

作者： Taylor, Thomas E. L'Ecuyer, Tristan S. Slusser, James R. Stephens, Graeme L. Goering, Christian D. Colorado State Univ USDA UV B Monitoring Res Program Ft Collins CO 80521 USA Colorado State Univ Dept Atmospher Sci Ft Collins CO 80523 USA

This paper describes a number of practical considerations concerning the optimization and operational implementation of an algorithm used to characterize the optical properties of aerosols across part of the ultraviolet (uv) spectrum. The algorithm estimates values of aerosol optical depth (AOD) and aerosol single scattering albedo (SSA) at seven wavelengths in the uv, as well as total column ozone (TOC) and wavelength-independent asymmetry factor ( g) using direct and diffuse irradiances measured with a uv multifilter rotating shadowband radiometer (uv-MFRSR). A novel method for cloud screening the irradiance data set is introduced, as well as several improvements and optimizations to the retrieval scheme which yield a more realistic physical model for the inversion and increase the efficiency of the algorithm. Introduction of a wavelength-dependent retrieval error budget generated from rigorous forward model analysis as well as broadened covariances on the a priori values of AOD, SSA and g and tightened covariances of TOC allows sufficient retrieval sensitivity and res.lution to obtain unique solutions of aerosol optical properties as demonstrated by synthetic retrievals. Analysis of a cloud screened data set (May 2003) from Panther Junction, Texas, demonstrates that the algorithm produces realistic values of the optical properties that compare favorably with pseudo-independent methods for AOD, TOC and calculated Angstrom exponents. Retrieval errors of all parameters (except TOC) are shown to be negatively correlated to AOD, while the Shannon information content is positively correlated, indicating that retrieval skill improves with increasing atmospheric turbidity. When implemented operationally on more than thirty instruments in the Ultraviolet monitoring and res.arch program's (uvMRP) network, this retrieval algorithm will provide a comprehensive and internally consistent climatology of ground- based aerosol properties in the uv spectral range that can be used

关键词： ultraviolet aerosol retrieval

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Estimating winter wheat biomass based on LANDSAT TM and MODIS data

Estimating winter wheat biomass based on LANDSAT TM and MODI...

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Conference on Remote Sensing and Modeling of Ecosystems for Sustainability

作者： bao, Yansong Gao, Wei Gao, Zhiqiang Nanjing Univ Informat Sci & Technol Sch Remote Sensing Nanjing 210044 Peoples R China Colorado State Univ Nat Resource Ecol Lab USDA UV B Monitoring & Res Program Ft Collins CO 80521 USA East China Normal Univ Key Lab Geog Informat Sci Shanghai 200062 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China

ISBN: (纸本)9780819473035

biomass can indicate plant growth status, so it is an important index for plant growth monitoring. This paper focused on the methodology of estimating winter wheat biomass based on LANDSAT TM and EOS MODIS images. In order to develop the method of retrieving wheat biomass from remote sensing data, field measurements were conducted when LANDSAT satellite passed over the study region. In the experiments, five LANDSAT TM images were acquired res.ectively at early erecting stage, jointing stage, caring stage, flowering stage and grain-filling stage of winter wheat, and experiment sites' wheat biomass was measured at each stage. based on the TM and MODIS images, spectral indices such as NDVI, RDVI, EVI, MSAVI, SIPI and NDWI were calculated. Then the correlation coefficients between wheat biomass and spectral indices of the experiment sites were computed. According to the correlation coefficients, the optimal spectral indices for estimating wheat biomass were determined. The best-fitting method was employed to build the relationship models between wheat biomass and the optimal spectral indices. Finally, the models were used to estimate wheat biomass based on TM and MODIS data. The RMSE of estimated biomass was not more than 66.403 g/m(2).

关键词： LANDSAT TM EOS MODIS biomass retrieval spectral indices

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The study of urban sprawl and simulation based on remote sensing and CLUS model

The study of urban sprawl and simulation based on remote sen...

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Conference on Remote Sensing and Modelling of Ecosystems for Sustainability IV

作者： Gao, Zhiqiang Gao, Wei Jie, Zhang Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing Peoples R China Colorado State Univ Nat Resource Ecol Lab USDA UV B Monitoring & Res Program Ft Collins CO 80523 USA

ISBN: (纸本)9780819468277

based on remote sensing data, we extracted the dynamic land use/cover change, reconstructed the basic landscape process in beijing during 1975 to 2001, and predicted the layout of beijing in the next 20 years using CLUS-S model. After analyzing, we found that: (1) While the sprawl rate of the city was accelerating gradually and the urban area increased sharply between 1975 and 2001, the area of plantation was decreased and the problem of land degradation and fragmentation of the ecological environment was more and more serious;(2) based on all six simulation scenarios, the area of plantation was going to be reduced gradually, and the integrity of landscape of plantation area was going to be further collapsed with the grads of urban-rural ecotone.

关键词： China urban sprawl CLUS model landscape analysis

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Spatial distribution and temporal variation of ecological capital and their relation to climate change and the changes of land use and land cover on the northern slope of the Tianshan Mountain, China

Spatial distribution and temporal variation of ecological ca...

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Conference on Remote Sensing and Modelling of Ecosystems for Sustainability IV

作者： Zhang, Qing Chen, Xiuwan Gao, Wei Zhang, Xianfeng Zhou, Kefa Wang, Xinli Peking Univ Inst Remote Sensing & Geog Informat Syst Beijing 100871 Peoples R China Colorado State Univ USDA UV B Monitoring & Res Program Nat Resource Ecol Lab Ft Collins CO 80523 USA Chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China

ISBN: (纸本)9780819468277

Ecological capital of an ecosystem is the total value of the direct biological products in the system and the value of ecological service. The assessment of ecological capital is a new res.arch area emerged from the challenge in the interdisciplinary res.arch of ecology and social development. It is fundamental to establish a green national economy accounting system. Scientific evaluation of ecological capital is helpful for considering ecological cost in making the decision for economic development, and it is demanded for sustainable development. In this study, a quantitative assessment model of ecological property has been developed based on the analysis of per unit yield in the conventional ecology together with the utilization of remote sensing data from the Landsat TM, CbERS, MODIS, and NOAA database, land use and land cover data, and field measurements. The study area covers Changji Autonomous District, Xinjiang, China on the northern slope of Tianshan Mountain that is located in a typical and area. Dynamic monitoring of ecological capital was performed using remote sensing techniques. Spatial distribution and temporal variation of ecological properties were characterized. The effects of land cover and land use as well as climate change on those variation and distribution were analyzed. The res.lts show a significant increase in the ecological capital during 1990-2003. The spatial distribution of ecological properties is characterized by a negative gradient from higher altitudes to lower altitudes (plains) and from oases to deserts, which is consistent with the zonal distribution of vegetation in and areas. Due to global warming, the climate in Xinjiang has been changed into a warmer and wetter environment during the last 50 years, which improves the plant growing conditions in the alpine regions, piedmont hilly regions, and the oases. On the other hand, the natural environment in the and and semiarid regions in northwest China becomes more severe, and the str

关键词： ecological capital climate change land use land cover

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A study of retrieval land surface temperature and evapotranspiration in res.onse to LUCC based on remote sensing data

A study of retrieval land surface temperature and evapotrans...

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Conference on Remote Sensing and Modelling of Ecosystems for Sustainability IV

作者： Liu, Chaoshun Gao, Wei Gao, Zhiqiang Sch Remote Sensing NUIST Sino Amer Cooperat Remote Sensing Ctr Nanjing 210044 Peoples R China Chinese Acad Sci Inst Geograph Sci & Nat Resources Res Beijing 100101 Peoples R China Colorado State Univ Nat Resource Ecol Lab USDA UV B Monitoring & Res Program Ft Collins CO 80523 USA

ISBN: (纸本)9780819468277

In this study landsat TM/ETM+ was used to analyze the spatial distribution change of LST and ET in terms of LUCC difference from 1987 to 2000. The LST was retrieved by Qin et al.'s algorithm and the daily ET was estimated using the SEbAL model. The res.lts show that the LST and ET of 2000 both were completely different from those of 1987 due to the LUCC variation in the 13 years. The land use/cover characteristics mainly controlled the spatial distribution of the LST and ET. The analysis indicated that LST possessed evidently negative correlation with the ET for all land cover types. The analysis of LST and ET in res.onse to LUCC would help the decision maker for better future planning to protect ecological environment.

关键词： land use/cover change (LUCC) land surface temperature (LST) evapotranspiration (ET) Landsat TM/ETM

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Construction of land data assimilation system based on EnKF technology and community land model

Construction of land data assimilation system based on EnKF ...

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Conference on Remote Sensing and Modelling of Ecosystems for Sustainability IV

作者： Lu, Qifeng Gao, Wei Gao, Zhiqiang Wu, Wanli Dong, Chaohua Yang, Zhongdong Zhang, Peng Du, bingyu Slusser, James China Meteorol Adm LRCVES CMA Key Lab Radiomet Calibrat & Validat Environm Sate Beijing Peoples R China Colorado State Univ Nat Resource Ecol Lab USDA UV B Monitoring & Res Program Ft Collins CO 80523 USA Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing Peoples R China Natl Ctr Atmospher Res Climate & Global Dynam Div Boulder CO USA Int Ctr Desert Affairs Res Sustainable Dev Arid & Urumqi Peoples R China Nanjing Univ Informat Sci & Technol Nanjing Jiangsu Peoples R China

ISBN: (纸本)9780819468277

In order to better use the land products retrieved from the remotely sensed datasets in the land surface model and weather/climate model, the Land Data Assimilation Systems (LDAS) based on EnKF Technology and Community Land Model has been developed at NSMC/CMA. In the context of numerical weather prediction applications, LDAS can provide optimal estimates of land surface state initial conditions by integrating with an ensemble of land surface models, the available atmospheric forcing data, remotely sensed observations of precipitation, radiation and some land surface parameters such as land cover and leaf area index. The validation from Yucheng comprehensive experiment site indicates that the preliminary res.lts obtained are still inspiring. There are still many detailed work to do for the routine operation of LDAS, such as how to get dynamic P in 3dvar, how to select the spacing interpolation algorithm, etc.

关键词： land data assimilation system EnKF technology community land model

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Correlations of snow depth retrieved from SSM/I with precipitation and temperature over China

Correlations of snow depth retrieved from SSM/I with precipi...

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Conference on Remote Sensing and Modelling of Ecosystems for Sustainability IV

作者： Gao, Wei Lu, Qifeng Gao, Zhiqiang Wu, Wanli Du, bingyu Slusser, James Colorado State Univ Nat Resource Ecol Lab USDA UV B Monitoring & Res Program Ft Collins CO 80523 USA China Meteorol Adm LRCVES CMA Key Lab Radiometr Calibrat & Validat Environm Sat Beijing Peoples R China Chinese Acad Sci Inst Geograph Sci & Nat Resources Res Beijing Peoples R China Natl Ctr Atmospher Res Climate & Global Dynam Div Boulder CO 80307 USA Int Ctr Desert Affairs Res Sustainable Dev Arid & Semi Arid Lands Urumqi Peoples R China Nanjing Univ Informat Sci & Technol Nanjing Jiangsu Peoples R China

ISBN: (纸本)9780819468277

Climatological data during the period 1978-2005 in China were analyzed to characterize the relationships between temperature, precipitation (rainfall and snow), and snow as well as their temporal variations. Data at forty-two observation sites among 160 sites are chosen for the analysis. The China domain is broadly divided into northeastern, northwestern, and Tibet regions. The res.lts show that the evolution of snow depth and area is in good agreement with that from previous studies using different datasets. An abrupt jump occurred in the year 1990. Oscillations with a wavelength of about five years can be identified in the time sequence. Significant correlations between snow depths, snow covers, temperatures. and precipitation are found for various time frames at different sites. The cold air mass comes from the northwestern and northeastern China and moves into the southern China through an aisle between them. This cold air transportation brings the influence of snow information on the temperature and precipitation into the southern China. In the sensitive. region, the snow information in the three regions has strong effects on the temperature and precipitation. The actual effect of snow information on temperature and precipitation is the res.lt of competition among these three snow covered regions. The snow information in the Tibet region has a larger scale effect on the temperature and precipitation than in the other two regions. This is in accordance with its characteristics that are able to inspire the larger scale atmospheric circulations.

关键词： correlation analysis temperature precipitation snow depth

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Analysis of temporal variations of surface albedo from MODIS

Analysis of temporal variations of surface albedo from MODIS

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Conference on Remote Sensing and Modeling of Ecosystems for Sustainability III

作者： Gao, Wei Lu, Qifeng Gao, Zhiqiang Wu, Wanli Du, bingyu Slusser, James Colorado State Univ USDA UV B Monitoring & Res Program Nat Resource Ecol Lab Ft Collins CO USA

ISBN: (纸本)0819463779

Land surface albedo is a key parameter in modeling radiative transfer in the atmosphere. Simulated climates are sensitive to specified albedo in models. The MODIS bRDF/Albedo Science Data Product repres.nts the latest attempt at providing a dataset suitable for climate model comparisons. It is necessary to analyze the feature of white-sky and black-sky albedo, before its use in land surface models. White-sky (diffuse) and black-sky albedo (direct at local solar noon) in China from MODIS based on Lucht algorithm are calculated and analyzed. The differences of white-sky and black-sky albedo, for different land use/land cover are compared. The derived albedo exhibits clear interannual variation with large variation in Northern China. black-sky albedo and white-sky albedo are characterized with different features.for different land covers.

关键词： temporal variations albedo MODIS black sky white sky

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