基于时间序列MODIS数据的贵州省森林物候地域分异

森林物候是气候与环境变化的重要指示器,对于陆地植被生态环境监测具有重要的意义。以2011～2013年的MODIS NDVI(归一化植被指数)为时间序列数据,采用Savizky-Golay(S-G)滤波平滑和动态阀值法,提取出贵州省2012年森林物候的生长起始日期(SOS)、生长结束日期(EOS)、生长季长度(LOS)和生长季振幅(AOS)4个参数,分别将提取的森林物候参数与经度、纬度和海拔做相关性分析。研究结果显示:(1)贵州省森林物候参数与纬度相关性整体较弱,因此贵州省森林物候纬度地带性地域分异的不显著;(2)贵州省森林物候生长起始期、生长季长度与经度呈极显著相关,而森林物候生长结束期与经度呈低度相关,整体上贵州省森林物候参数海陆(经度)地带性地域分异显著;(3)贵州省森林物候生长起始期、生长结束期与海拔呈显著相关,而森林物候生长季长度与海拔呈极显著相关,因此贵州省森林物候参数垂直(海拔)地带性地域分异的十分显著。     

Polychlorinated Biphenyls (Pcbs) Pollution in Sea of Japan

Deep waters of the Sea of Japan and surface waters of the Pacific Coast of Honshu and the northeast Sea of Japan were analysed for polychlorinated biphenyls (PCBs) pollution. the ΣPCB concentrations in solution in the Sea of Japan (50-3000 m) were between 140 and 1230 fg dm_-3. the space-integrated surface water concentration near the Pacific coast of northern Honshu was 140 fg dm_-3and for the surface water of the Sea of Japan was 230 fg dm_-3. Based on these analyses four water masses were deduced in the Sea of Japan during the summer months. It is shown for the first time in the Sea of Japan that polychlorinated biphenyls are excellent chemical indicators of not only the anthropogenic pollution, but also water masses.     

微波催化燃烧技术处理印刷包装行业VOCs

微波催化燃烧技术将微波辐照与吸波型催化剂相结合,可用于对挥发性有机化合物(VOCs)进行催化燃烧处置。研制了Pt/CuMnCeO_x/堇青石和Pt/CuMnCeO_x/纳米陶瓷整体式蜂窝状催化剂,并开发了微波催化燃烧VOCs的装置,将其应用于印刷包装行业的VOCs治理。通过操作条件的优化,考察了微波催化燃烧技术对VOCs的实际处理效果。同时,对催化剂表面形貌、比表面积和晶体结构等进行了测试分析。结果表明：Mn₃O₄/Mn₂O₃、CeO₂/Ce₂O₃、CuMn₂O₄和PtO等尖晶石的存在降低了反应温度、提高了储氧释氧能力和催化剂活性;催化剂的介孔结构和较大的比表面积有利于VOCs在孔隙内部的扩散,并可延长VOCs在催化剂上的停留时间。在催化剂床层体积330 L、微波功率13.6 kW、进气质量浓度1 520 mg·m^-3和进气量440 m³·h⁻¹的条件下,床层温度可达到420 ℃,此时催化剂床层温度及VOCs去除率保持稳定。当进气质量浓度分别为约4 500 mg·m⁻³和2 800 mg·m⁻³时,VOCs的去除率分别为90%和96%。考察燃烧热量发现,大气量的VOCs在催化剂表面的停留时间短且带走热量多,从而导致VOCs去除率下降;高浓度VOCs在燃烧时会因释放出更多热量,从而提高床层温度和VOCs去除率。在确保催化剂表面活性位点充足的条件下,微波催化燃烧工艺适合处理中高浓度的印刷包装行业VOCs。同时,利用VOCs燃烧释放的热量来保持床层高温,还可达到节能降耗的目的。本研究可为印刷包装行业的VOCs治理提供参考。     

地下水中潜在危害有机物识别与筛选方法

针对地下水中频繁检出的各类有机物,运用理论方法定量计算污染物对地下水的危害系数,对有机物的污染调查、地下水污染防治具有一定的指导意义。为研究有机物对地下水的危害性,汇总了535项有机物,目前这些指标在国内外水质标准中均没给出标准值。从有机物的自身属性入手,假定所有物质处于相同的外界环境中,经过包气带吸附、降解、挥发等作用,分析其进入地下水的难易程度。利用美国环保局的软件EPI Suit4.10,获取了指标的有机碳吸附系数(Koc)、半衰期(DT50)和亨利常数(KH),并结合毒性参数基于健康的评价基准值,构建了污染物潜在危害参数体系。运用3种方法计算有机物的危害系数H、污染指数G和衰减系数K,对比3种计算结果,筛选出100项潜在危害有机物。分析表明,所筛选出的100项指标毒性较大、难挥发,并且有机物的Koc对污染指数(G)和衰减系数(K)的贡献比DT50、KH更大。     

DECISION PARAMETERS FOR COMBINED USE OF EFFLUENT DISCHARGES,SURFACE FLOWS,AND GROUND WATER1

ABSTRACT: Decision parameters affecting combined use of effluent discharges and surface flows and ground water available at Gillespie Dam on the Gila River in Arizona are identified and analyzed. Hydrologic, economic, legal, and institutional parameters are considered separately and in combination. The interrelationships of irrigation subsystems, water use functions, institutional involvement, economic and legal constraints are illustrated. Recent hydrologic studies indicate that the natural flow of the Gila River will increase with the discharge of Phoenix sewage effluent and then there will be a drastic decline when the Palo Verde Nuclear Generating Station commences in 1985. Competition for any increases in effluent discharges and surface flows could be ameliorated through the combined efforts of existing or reorganized entities resulting in sharing of costs and benefits. The analysis leads to recommendations concerning joint use of facilities, proration of fixed and variable costs, and creation of a mutual water company.     

ESTIMATION OF THE HIEC1 LOSS PARAMETERS FOR ROUTING THE PROBABLE MAXIMUM FLOOD1

ABSTRACT: Twenty storm events were used to select design values of the HEC1 loss parameters STRTL and CNSTL in order to route the probable maximum flood, PMF, through the Englewood watershed, Ohio. The parameter STRTL represents the initial volume of water lost due to interception and incomplete saturation of the soil prior to the storm. The parameter CNSTL represents a continuous loss rate and depends only on the watershed. When optimized from each storm event, STRTL varied between 0.0 and 3.4 inches with an average of 1.0 inch; CNSTL varied between 0.02 and 0.26 inch/hour, and it followed a normal probability distribution with a mean of about 0.1 inch/hour. The absence of correlation between optimum CNSTL values and each of total rainfall, total loss, and runoff duration supported the selection of the mean CNSTL as a design value. PMF routing through the Englewood watershed revealed that the PMF at the outlet is not sensitive to STRTL, but highly affected by CNSTL variations. The insensitivity to STRTL was due to the presence of a dam at the outlet of the watershed that caused the buildup of water in the watershed, thereby masking the storage effect of STRTL. The peak PMF increased by about 27 percent when the design CNSTL was decreased to 0.05 inch! hour, and decreased by about 18 percent when the design CNSTL was increased to 0.15 inch/hour.     

AQUIFER PARAMETERS FROM CONSTANT DRAWDOWN NONSTEADY-LEAKY TYPE CURVES1

ABSTRACT: A drain function and set of type curves were defined for the mathematical solution that represents one-dimensional flow under nonsteady conditions in a leaky aquifer for the constant drawdown boundary condition. A match point procedure was developed for determining the aquifer parameters transmissivity, storage coefficient, and leakance based on the drain function and type curves. Use of the procedure is illustrated by an example that utilizes simulated aquifer drawdowns and flowrate data. The drain function and type curves developed in this investigation include the effects of leakage for the constant drawdown boundary condition, which is not included in the existing drain function and type curve found in the literature. Thus, a new set of type curves was developed that can be used to analyze drawdowns for one-dimensional flow in a leaky aquifer with constant drawdown at a line sink. Applications would include flow to a canal or river, drainage of agricultural lands, and dewatering associated with strip mining operations.     

Impacts of some meteorological parameters on SO2 and TSP concentrations in Erzurum, Turkey

The air pollution is the one of the most important environmental problems in Erzurum, situated in the eastern of Turkey, during winter periods. The unfavorable climate as well as the city’s topography, and inappropriate urbanization cause serious air pollution problems. The air pollutant concentrations in a city have a close relationship with its meteorological parameters. In the present study, the relationship between daily average total suspended particulate (TSP) and sulphur dioxide (SO₂) concentrations with meteorological factors, such as wind speed, temperature, relative humidity, pressure and precipitation, in 1995–2002 winter seasons was statistically analyzed using the stepwise multiple linear regression analysis. According to the results obtained through analysis, higher TSP and SO₂ concentrations are strongly related to colder temperatures, lower wind speed, higher pressure system and weakly lower precipitation and higher relative humidity. The statistical models of SO₂ and TSP including meteorological parameters gave R² of 0.74 and 0.88, respectively. Furthermore, the correlation between the previous day’s SO₂, TSP concentrations and actual concentrations of these pollutants on that day was investigated and found as 0.84 and 0.53, respectively. In order to develop this model, previous day’s SO₂ and TSP concentrations were added to the equations. The new model for SO₂ enhanced considerably (R² = 0.92), but for TSP new model was not enhanced (R² = 0.89).     

两种应用场景下NDVI时间序列数据拟合方法研究

植被覆盖指数（NDVI）时间序列数据集包含地表植被的长势、生长周期、时空变化等信息,其拟合重建结果可应用于物候信息提取、生态质量评价、人类活动扰动识别、覆被变化动态监测等方面。基于TIMESAT软件,选取物候参数提取和扰动识别2个应用场景,结合地面站点数据和Jacknife法模拟数据,对比分析非对称高斯函数拟合法（AG法）、双Logistic函数拟合法（D-L法）和Savitzky-Golay滤波法（S-G法）3种方法的拟合效果。结果表明：（1）3种方法拟合重建后提取的生长开始时间（SOS）、生长结束时间（EOS）、生长周期（LOS）等物候参数接近站点数据,AG法和D-L法保持NDVI时序曲线整体变化特征的能力较强,提取的SOS和EOS更接近站点数据;（2）人类活动扰动识别应用场景中,S-G法在滤波时能够最大限度地保留时序曲线细节变化,恢复速率相关系数达到0.618,回归估计标准差低于AG法和D-L法,因此识别精度最优。     

辽东湾地区~(137)Cs大气沉降研究

利用137Cs示踪技术的前提条件是了解137Cs的大气沉降历史,从而准确求算区域环境中137Cs的背景值.本文利用日本秋田、东京及新泻地区137Cs年沉降数据,并结合相应的降水数据进行修正,对辽东湾地区137Cs的大气沉降进行了定量研究.结果表明,辽东湾地区137Cs的大气沉降趋势与北半球基本一致;1957—2008年辽东湾地区137Cs大气总沉降通量的模拟结果为1536 Bq·m-2(衰变校正至2009年),与该地区土壤中137Cs背景值较为接近;20世纪50年代末60年代初频繁的大气核试验和1986年的切尔诺贝利核事故是1963年和1986年两个137Cs沉降峰值产生的原因;1990年以后,沉降在地表的137Cs在风力侵蚀作用下,发生再悬浮,使得大气中137Cs沉降通量再次出现量级变化明显.福岛核事故产生的核素沉降对研究区的137Cs沉降通量的影响并不明显.