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采用美国的USB 2000 光纤光谱仪对塔希提黑珍珠?黑蝶贝?人工染色处理珍珠及三角帆蚌样品的可见吸收光谱进行了测试和研究?结果表明:塔希提黑珍珠及黑蝶贝在可见光区内存在3 处特征的吸收宽谱带(即a 带 b 带和c 带),与人工染色黑色珍珠和三角帆蚌的可见吸收光谱特征具本质上的差别, 因而具有一定的鉴定意义?对部分样品的激光拉曼光谱进行了测试,并对塔希提黑珍珠的可见吸收光谱起因一并予以了剖析。

 平流层臭氧层变薄导致地面紫外辐射增加, 紫外辐射的生态、气候学及环境效应使太阳紫外辐射的观测研究逐渐成为辐射研究的前沿问题。地基紫外辐射联网观测是获得紫外辐射时空分布的基础, 而定期进行辐射表的标定是获取正确的、具有可比性的观测数据的基本保证。利用USB 2000 紫外/ 可见辐射光谱仪, 采用标准灯传递能量的标定方法建立了紫外辐射表和光合有效辐射表标定系统, 标定后的紫外辐射表不确定度为5 %, 光合有效辐射表不确定度为5 %, 能够很好地满足世界气象组织标准。该标定方法简单易行、运行费用低且精度较高, 能够很好地进行中国辐射观测网中紫外与光合有效辐射表的标定工作。

准确掌握治疗靶组织内光敏剂含量信息的实时变化情况对于理解光动力反应进程、疗效推进、制定合理的光动力治疗(photodynamic therapy,PDT)方案具有重要指导意义。本研究采用经典方法——荧光光谱无损检测技术,对鲜红斑痣(Port wine stains,PWS)PDT治疗过程中患区皮肤光敏剂的含量信息进行实时监测。提高监测信息的可信度,并结合临床退色效果给出与疗效相关的较明确的规律。研究中运用的光敏剂是临床上常用的PSD007,主要成分血卟啉单甲醚(Hematoporphyrin monomethylether, HMME)。主要做了以下几方面的工作。

为解决海上油污染的现场监测问题, 研发了一种DPS1-1 型海上漂油现场监测系统。通过分析油膜的反射系数, 反射光谱等综合参数, 可以判断油膜的有无及厚薄。该仪器可用于舰船和浮标的定点或走航的现场测量。试验结果表明, 采用光谱分析法判断油污染的方案是可行的。

This study was conducted to estimate the fraction of Intercepted Photosinthetically Active Radiation (fIPAR) in an olive orchard. The method proposed to estimate fIPAR in olive canopies consisted of a coupled radiative transfer model that linked the 3D Forest Light Interaction Model (FLIGHT) and the Orchard Radiation Interception Model (ORIM). This method was used to assess the estimation of instantaneous fIPAR as a function of planting grids, percentage cover, and soil effects. The linked model was tested against field measurements of fIPAR acquired for a commercial olive orchard, where study plots showing a gradient in the canopy structure and percentage cover were selected. High-resolution airborne multispectral imagery was acquired at 10 nm bandwidth and 15-cm spatial resolution, and the reflectance used to calculate vegetation indices from each study site. In addition, simulations of the land surface bidirectional reflectance were conducted to understand the relationships between canopy architecture and fIPAR on typical olive orchard planting patterns. Input parameters used for the canopy model, such as the leaf and soil optical properties, the architecture of the canopy, and sun geometry, were studied in order to assess the effect of these inputs on the Normalized Difference Vegetation Index (NDVI) and fIPAR relationships. FLIGHT and ORIM models were independently assessed for fIPAR estimation using structural and ceptometer field data collected from each study site, yielding RMSE values of 0.1 for the FLIGHT model, while the specific olive simulation model by ORIM yielded lower errors (RMSE = 0.05). The reflectance simulations conducted as a function of the orchard architecture confirmed the usefulness of the modeling methods for this heterogeneous olive crop, and the high sensitivity of the NDVI and fIPAR to background, percentage cover, and sun geometry on these heterogeneous orchard canopies. The fIPAR estimations obtained from the airborne imagery through predictive relationships yielded RMSE error values of 0.11 when using FLIGHT to simulate both the canopy reflectance and the fIPAR of the study sites. The coupled FLIGHT+ORIM model yielded better results, obtaining RMSE = 0.05 when using airborne remote sensing imagery to estimate fIPAR.

Transport of sediment and organisms in rivers, estuaries and the near-shore ocean is dependent on the dynamics of waves, tides, turbulence, and the currents associated with these interacting bodies of water. We present measurements of waves, currents and turbulence from color and polarization remote sensing in these regions using our Airborne Remote Optical Spotlight System-Multispectral Polarimeter (AROSS-MSP). AROSS-MSP is a 12-channel sensor system that measures 4 color bands (RGB-NIR) and 3 polarization states for the full linear polarization response of the imaged scene. Color and polarimetry, from airborne remotely-sensed time-series imagery, provide unique information for retrieving dynamic environmental parameters relating to sediment transport processes over a larger area than is possible with typical in situ measurements. Typical image footprints provide area coverage on the water surface on the order of 2 square kilometers with 2 m ground sample distance.

The ability to appropriately modify physiological and morphological traits in response to temporal variation should increase Wtness. We used recombinant hybrid plants generated by crossing taxa in the Piriqueta caroliniana complex to assess the eVects of individual leaf traits and trait plasticities on growth in a temporally variable environment. Recombinant hybrids were used to provide a wide range of trait expression and to allow an assessment of the independent eVects of individual traits across a range of genetic backgrounds. Hybrid genotypes were replicated through vegetative propagation and planted in common gardens at Archbold Biological Station in Venus, Florida, where they were monitored for growth, leaf morphological characters, and integrated water use eYciency (WUE) (C isotope ratio; 13C) for two successive seasons. Under wet conditions only leaf area had signiWcant eVects on plant growth, but as conditions became drier, growth rates were greatest in plants with narrow leaves and higher trichome densities. Plants with higher WUE exhibited increased growth during the dry season but not during the wet season. WUE during the dry season was increased for plants with smaller, narrower leaves that had higher trichome densities and increased reXectance. Examination of alternative path models revealed that during the dry season leaf traits had signiWcant eVects on plant growth only through their direct eVects on WUE, as estimated from 13C. Over the entire growing season, plants with a greater ability to produce smaller and narrower leaves with higher trichome densities in response to reduced water availability had the greatest growth rate. These Wndings suggest that plants making appropriate changes to leaf morphology as conditions became dry had increased WUE, and that the ability to adjust leaf phenotypes in response to environmental variation is a mechanism by which plants increase Wtness.

Due to the poor condition of soil and micro-climate condition, the mudstone area in the southwestern Taiwan has been difficult for plants to grow. The area is always in such a bare condition that it is nicknamed “Moon World.” Serious erosion and natural disasters in the mudstone area are the significant problems for soil and water conservation, and the area of bald mudstones is expanding. Statistical data show that bare area has increased 3 times during the past 10 years. The mudstone area in the southwestern Taiwan was hard to plant and then it always in bare condition which got a nickname of The Moon World. The distribution of each land-use type in mudstone area, and spatial information in years were integrated into GIS by ArcView. In the respect of ecosystem, ecological index in different periods were calculated based upon landscape ecological theory. To explain its meanings and the danger behind the bare mudstone area, the results indicated that mosaic gathering was caused by mudstone and thorn bamboo. The results illustrated that the ecological factor of landscape such as patch shape factor, and Shannon evenness factor that have significant canonical correlation with water qualities and erosion of the study area. In study area, there are many styles of fracture, variation, and mosaic distribution landscape.

The rapid spread of nonnative plant species have caused considerable negative impact to the biodiver sity and ecosystems in Taiwan. To better under s tand the status and to suppor t researcher s and decision makers to develop strategies and remedies for this problem, it is necessary to obtain accurate spatial information and the progres sion about the invasions of foreign species into native ecocommu ni ty. The availability of hyper spect ral and high resolution satellite data provides researcher s an oppor tuni ty to pursue more complex analysis and have a great potential to achieve better performance and results in an invasive plants investigation. High resolution images provide detail spatial informa tion about the target areas but are often limited to single or few spectral bands. On the other hand, hyperspect ral data consist of tens to hundreds of contiguous bands but lack of spatial details. Therefore, a combination of both types of data is likely to be an optimal approach to the mapping of alien plants. However, with the large data volume and high data dimensionality, the major challenge of using hyperspect ral and high resolution data together is to extract useful information effectively and efficiently. This paper present s a work in progres s of developing a systematic method to use hyperspect ral and high resolution satellite images to identify an invasive plant (horse tamarind, Leucaena Leucocephala ) that is spreading in an alarming rate in southern Taiwan. The developed method first locates "areas of interes t" where target species is likely to populate most densely. Then a two- level analysis procedure is implemented using hyperspect ral and high resolution satellite images to identify and map the distribution of target species. The first phase of the procedure is to analyze hyper spect ral images with selected (helpful) features to obtain a preliminary result. The second phase is to isolate the areas where discrimination of target plant species is not satisfactory and to improve the accuracy of discrimination with the analysis of canopy structure s in high resolution satellite images. Verification with ground truth samples indicates that the developed method of combining high resolution and hyperspect ral images analysis is an effective and efficient approach to detect invasive plant s in a large area.

The ability to identify diseases in an early infection stage and to accurately quantify the severity of infection is crucial in plant disease assessment and management. A greenhouse study was conducted to assess changes in the leaf spectral reflectance and fluorescence of young tobacco plants during viral infections with the aim to evaluate the remote sensing spectral measurements as a tool for early identification and discrimination of different diseases. At the growth stage of 2-4 expanded leaf, the plants were inoculated with tobacco sap from leaves with clearly manifested infection symptoms of the four most widely spread in Bulgaria viruses: Cucumber mosaic virus - CMV, Tomato spotted wilt virus - TSWV, Tomato mosaic virus - ToMV and Potato virus Y - PVY. The leaf reflectance and fluorescence spectra were collected on the 7th day after inoculation using an Ocean Optics USB2000 spectrometer in the spectral ranges 450-850 nm and 600-850 nm, respectively. Specific differences in reflectance spectra between virus-infected and uninfected tobacco leaves were observed in four wavelength intervals: green (520-580 nm), red (640-680 nm), red edge (690-710 nm) and near infrared (720- 760 nm). Results of statistical analysis by applying Student’s t-criterion showed statistically significant differences against reflectance data of uninfected leaves at least in three of the investigated spectral ranges in dependence on the virus specificity. The fluorescence spectra of all infected leaves differed statistically significant in the spectral range 640-680 nm. The results of spectral analysis qualify the two remote sensing techniques as a promising tool for cost-effective, non-destructive method for early detection of viral infections.

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