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91.
92.
复合式绿化林带在港区边界噪声防治中的应用 总被引:6,自引:1,他引:6
通过理论及实际研究复合式绿化林带降噪效果,设想通过在港区边界种植复合式绿化林带来解决港区噪声超标的问题,同时起到保护和保持生态平衡的作用。 相似文献
93.
94.
Summary. We tested the hypothesis that aggregation behaviour of the
firebrat, Thermobia domestica (Packard) (Thysanura: Lepismatidae), an
inhabitant of enclosed microhabitats, is mediated, at least in part, by
a pheromone. Individual insects were released into the central chamber
of a 3-chambered olfactometer and test stimuli were placed in lateral
chambers. Paper discs previously exposed for 3 days to 10 female, male,
or juvenile T. domestica were all preferred by female, male, or juvenile
T. domestica over unexposed paper discs, indicating the presence of an
aggregation/arrestment pheromone. In additional experiments, frass and
scales from female T. domestica, tested singly and in combination,
proved not to be the source of the pheromone. Physical contact was
required for pheromone recognition, indicating that the pheromone
arrests rather than attracts conspecifics. Arrestment by the
long-tailed silverfish, Ctenolepisma longicaudata Escherich
(Thysanura: Lepismatidae), but not by the common silverfish, Lepisma
saccharina L. (Thysanura: Lepismatidae), to T. domestica exposed
paper discs suggests closer phylogenetic relatedness between C.
longicaudata and T. domestica, than between C.
longicaudata and L. saccharina. Whether C.
longicaudata or L. saccharina produce an aggregation
signal, and whether T. domestica respond to this signal is unknown.
Received 10 June 2002; accepted 30 September 2002. 相似文献
95.
随着我国集装箱港口吞吐量持续增长,港区大气污染物排放亦日益增加,港作机械等非道路移动源排放更逐渐成为公众关注的焦点。借鉴OFFROAD模型的基本方法,通过调查分析集装箱港区作业机械的保有量、活动水平和设备参数等,修正排放因子,采用"自下而上"基于集装箱港作机械发动机活动水平的动力法建立集装箱港作机械大气污染物排放清单。并以南京港龙潭集装箱港区(NPLC)为案例,构建排放清单。结果表明:2014年NPLC港作机械排放总量为PM_(10) 4.25 t、PM_(2.5) 3.91 t、NO_x 82.98 t、SO_x 1.06 t、CO 23.84 t和HC16.39 t;集装箱拖车为最大排放贡献源,NO_x为高值排放污染物;与港区其他排放源相比,港作机械为颗粒物质(PM)与碳氢化合物(HC)的最大排放源。相较NPLC 2013年基于燃油消耗的研究,基于活动的排放量较低。 相似文献
96.
ABSTRACT: Increasing specialization separates animal production from cropland, complicating manure management. To assist policy targeting efforts, we highlight areas where on-farm use of manure may be problematic. Matching confined animal production with land, on the farm- rather than at the county-level, gives our analysis an advantage over previous studies in avoiding aggregation problems. With manure-based water quality problems, data aggregated to the county level may fail to convey the heterogeneity of animal production across regions and animal types. Aggregation bias blurs the distinction between areas with specialized animal production and those that merely have numerous animals. We estimate bias from using county aggregates, show its distribution spatially and by animal sector, and link it to concentration. Ongoing vertical integration in agriculture likely alters in-county variability in facility scale and scope, and may influence decisions about which data we should gather and use. 相似文献
97.
Mihailovic Dragutin T. Rao S. Trivikrama Hogrefe Christian Clark Richard D. 《Environmental Fluid Mechanics》2002,2(4):315-337
Experimental evidence indicates that there is a significant departure of the wind profile above the underlying surface consisting of patches of solid and liquid parts, and plant communities with different morphological from that predicted by the logarithmic relationship, which gives the values larger than those observed. This situation can seriously affect the transfer of momentum, heat and water vapor from the surface fluxes into the atmosphere.The object of this paper is to generalize the calculation of the exchange of momentum between the atmosphere and a very heterogeneous surface, find a general equation for the wind speed profile in a roughness sublayer under neutral conditions, and, then, derive aggregated roughness length and displacement height over the grid cell. The suggested expression for the wind profile is compared with some earlier approaches, using a common parameterization of aerodynamic parameters over the grid cell, and the observations obtained at an experimental site in Philadelphia, PA. 相似文献
98.
Dudek Daniel Golub Alexander Petsonk Annie Safonov George Saparov Mikhail 《Mitigation and Adaptation Strategies for Global Change》2002,7(2):155-172
Developing a transparent,accurate greenhouse gas (GHG) emissionsinventory is the first step toward buildingan effective GHG management system. Todate, GHG inventories have been conductedprimarily at national levels. Theinternationally accepted inventorymethodology developed by theIntergovernmental Panel on Climate Change(IPCC) is oriented to countrywideinventories. The electricity company RAOUESR is the largest single corporateemitter of GHG in the Russian Federation. The company is responsible for about 1/3 ofRussia's CO2 emissions; RAO's fossil fuelemissions are comparable to the fossil fuelemissions of the United Kingdom. The GHGinventory prepared by RAO is the first suchcorporate emissions inventory undertaken ina non-OECD country. In this article wepresent a detailed independent examinationof the methodology RAO applied for theinventory. We identify the most importantsources of uncertainty and we estimate theuncertainty. The main conclusion of theindependent review is that the methodologyutilized by RAO and the informationsupporting the methodology are reliable andpresent a reasonably accurate company-widepicture of RAO's CO2 emissions. The shareof other greenhouse gases is negligiblysmall and we did not focus on this fractionof RAO's GHG emissions. As a next step, RAOmay wish to conduct more precisefacility-by-facility inventories in orderto create a robust GHG emission managementsystem. 相似文献
99.
100.
A long-term study of temperature, pH, turbidity, suspended solid, salinity, dissolved oxygen, biochemical oxygen demand and ammonia nitrogen has been performed in a port and harbour region in India for four years from December 1996 to November 2000. Marine water quality results showed no regular trend. The mean monthly values of temperature, pH, turbidity, suspended solid, salinity, dissolved oxygen, biochemical oxygen demand and ammonia nitrogen were in the range of 22.64 ± 0.4 to 29.05 ± 1.37 °C; 7.65 ± 0.04 to 7.81 ± 0.13; 28.8 ± 14.7 to 64.2 ± 32.0 NTU; 283.5 ± 81.8 to 356.0 ± 159.7 mg/L; 29.78 ± 7.18 to 29.78 ± 1.04 ppt; 4.67 ± 0.50 to 6.01 ± 1.02 mg/L; 5.41 ± 1.92 to 7.56 ± 2.1 mg/L; and 0.25 ± 0.07 to 0.63 ± 0.49 mg/L, respectively. The results of correlation analysis showed that biochemical oxygen demand (BOD) was inversely correlated dissolved oxygen (DO) and poorly correlated with all other parameters. Turbidity and suspended solid were moderately correlated with each other while salinity was moderately correlated with other water quality parameters. In factor analysis, four factors were drawn out of the eight variables, which represented 74% of the variance of the original data. Factor I was related to suspended solid and turbidity. Factor II represented mainly temperature and DO showing inverse relation between these two. Factor III implied the degree of pollution at any monitoring station. Factor IV included pH and salinity. It could be concluded that the factor model represented almost all the variables. 相似文献