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101.
九华山森林生态系统生态服务价值评估   总被引:5,自引:0,他引:5  
基于LY/T1721-2008((森林生态系统生态服务功能评估规范>,采用实证研究、意愿调查、文献研究等方法,估算了九华山森林生态系统生态服务价值,结果表明:2009年,九华山森林生态系统生态服务价值为84 208.50万元,实物生产价值为4 359.06万元,生态服务价值是实物生产价值的19.31倍.各项生态服务功能价值大小顺序为:涵养水源>保育土壤>生物多样性保护>固碳释氧>森林游憩>净化大气环境>积累营养物质.可为九华山管委会制定旅游、社会经济发展规划,合理开发九华山生态旅游资源,提供理论依据和数据支撑,也可增强人们对九华山森林资源保护的自觉性和主动性.  相似文献   
102.
This study characterized sludge from an anoxic baffled reactor (ABR) used to treat textile dyeing wastewater. The process was run over 150 days. On day 152, five sludge samples were collected from compartments 1–5 of the ABR and a set of captive tests was conducted to investigate their particle size distributions (PSDs), dye biosorption and biodegradation properties, and dehydrogenase activity (DHA). The results indicated that the PSD of the five sludge samples from the ABR were similar. Methylene blue biosorption to the sludge samples followed the pseudo‐second‐order kinetic model and the actual biosorption process was controlled by external and intraparticle diffusion, simultaneously. After the sludge samples were cultivated for 24 h, the acid red GR dye removal efficiencies were 59.5, 68.3, 76.4, 61.5, and 65.4%, respectively. Eliminating dye biosorption, the dye biodegradation efficiencies were only 38.8, 46.3, 52.6, 48.3, and 46.0%, respectively. Furthermore, the DHA values were 28.2, 45.3, 56.5, 41.0, and 35.0 µg TF mL?1 h?1, respectively, and the DHA variation was in accordance with the dye biodegradation efficiency variation.  相似文献   
103.
When measuring reflectance spectra, it is very important to accurately extract chlorophyll fluorescence from elastic- scattering light in water-leaving radiance. The elastic scattering of light by water particles produces partially polarized light. In contrast, chlorophyll fluorescence in planktonic algae yields completely unpolarized light. These properties can be used to separate fluorescent signals from the water-leaving radiance and thus to determine chlorophyll concentration. The algal species Aureococcus anophagefferens was used to conduct a laboratory polarization experiment. For the tests, we used a field spectroradiometer and a polarizer; measurements were collected using two different observation modes. The chlorophyll fluorescence curve extracted through polarization shows an excellent match with the results obtained using the fluorospectro photometer for both measurement modes, suggesting that polarization-based chlorophyll fluorescence extraction may be feasible. The extracted fluorescence is more reliable at incident zenith angles ranging from 30° to 60°. For algae-containing water, the results improve with increasing chlorophyll concentration. This method could help improve chlorophyll concentration measurement and the remote-sensing detection of resulting harmful algae blooms.  相似文献   
104.
采用波形互相关技术获得Pn震相准确到时,然后应用滑动时窗相关法获取sPn与Pn震相的走时差,通过该走时差测定台湾海峡M6.2地震震源深度为14.7 km,并对测定的结果进行分析解释.对比本文计算结果与CAP方法的反演结果得出,本文研究方法更加方便、快捷、精确.  相似文献   
105.
The paper collects the records by the Fujian Digital Seismic Network of 40 shallow earthquakes in Taiwan with M_S≥5.0 from 1999 to 2013,analyzes the seismic phase(Pn,Sn phase)characteristics and travel-time rules,determines travel-time models and develops a seismic phase travel-time equation based on the two-step fitting algorithm.With the deduction of processing time and network delay time,this method can provide an accurate estimation of early warning time of Taiwan earthquakes for the Fujian region,and has been officially employed in the earthquake early warning system of Fujian Province.  相似文献   
106.
采用福建地区天然地震和人工爆破事件波形记录,通过一维离散小波变换(DWT)及4层小波包变换(WPT)对信号进行分解,提取出用于识别的4种波形小波特征:小波能量比特征、小波包能量比特征、小波包香农熵特征及小波包对数能量熵,此外还提取出P/S震相振幅比;采用BP神经网络对4种小波特征及分别加入P/S震相振幅比的组合特征进行识别效果检验,结果表明,单小波判据小波能量比特征识别效果好;双判据组合P/S震相振幅比和小波包对数能量熵的组合识别效果最好,可考虑作为实际天然地震与人工爆破在线自动识别系统的识别判据。  相似文献   
107.
感耦等离子体质谱法同时测定岩石中痕量元素的研究   总被引:3,自引:5,他引:3  
试验了含难熔组分的岩石样品的分解方法、熔剂用量,以及溶液中可溶盐量的控制和标准系列的熔剂匹配等问题;分别采用Re、Rh和In作内标,解决了基体效应及其基体导致的灵敏度漂移的影响,实现了不经分离富集直接用ICP-MS法测定岩石样品中34个痕量元素。方法测定限0.01~5μg/g,RSD(n=10)为2.6%~13%,已应用于地质试样分析,岩石标样分析结果与标准值相符。  相似文献   
108.
通过对山东蒙阴金伯利岩中富含硅酸盐不相容元素的锶钛铁矿族(LIMA系列)、磁铁铅矿族(HAYI系列)矿物及其相关的钛氧化物矿物的探针成分分析,对比南非Debeers,Jagersfontein及Bultfontein等地金伯利岩区的相似矿物研究,发现这类矿物的产出、相互关系及化学成分非常相近,与共生的金云母、碱性闪石等含水矿物一起,反映了富K,Ba,Ti,Zr,Nb,REE等不相容元素的流体对先前亏损的方辉橄榄岩的交代作用.LI-MA,HAYI系列矿物是流体对镁钛铁矿、铬尖晶石等的继承交代产物.不相容元素的局部富集还可形成一些罕见的矿物相,如REE-Ti及Zr-Ti氧化物.与之相关的呈海绵边或基质、空洞充填产出的钙钛矿、富锰钛铁矿、富锰锌尖晶石、柱红石、铬阿玛科矿等,则与碳酸盐化及金伯利岩岩浆晚期不相容元素的浓聚有关.对这类矿物化学成分及相互关系的研究,不但从微观角度揭示了不相容元素在部分上地幔岩石中的富集,提供了卷入交代流体的总成分目录,而且表明南非和山东金伯利岩地球化学性质的相似性  相似文献   
109.
甘肃及邻近地区M_L与M_S震级问题的探讨众所周知,震级问题是国内外地震学家非常关心并一直在探讨的重要课题。由实际观测资料发现,对于甘肃及邻近地区M_S≥4.0的地震(中长周期和短周期仪器都能记上的情况下)由短周期仪测定的体波震级M_L换算出的面波震...  相似文献   
110.
Sun  Huifang  Dang  Yaoguo  Mao  Wenxin 《Natural Hazards》2019,98(2):621-642

Regional agricultural drought vulnerability (RADV) is a complex problem caused by the interaction of various factors, and the combination of multiple dimensions of each subregion, factor index and time affects the RADV. Therefore, panel data should be used to reflect the actual situation of the region objectively and comprehensively. Current research on identifying key factors of affecting RADV is relatively scarce from the perspective of panel data. In view of this, in order to classify and identify the key factors, a new panel data grey combined method of comprehensive grey relational analysis (CGRA) and Max-CGRA clustering is proposed, which is applied to identify the key factors of RADV in China’s Henan Province. According to the identification results of key factors, the reasons for the change of RADV are further discovered, and the corresponding drought policies and countermeasures that need to be strengthened and controlled are presented. In addition, these results can also provide scientific basis for regional agricultural drought risk control.

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