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61.
Craig H. Bullock David A. Elston Neil A. Chalmers 《Journal of environmental management》1998,52(4):335-351
Stalking (deer hunting) is an important land use and activity in the Scottish Highlands, and deer managers have traditionally maintained large numbers of female deer in order to supply a guaranteed number of stags for stalking. Unfortunately, grazing by large numbers of deer conflicts with environmental objectives that are seeking to improve upland habitats and increase the area of native Caledonian Pine forest. This study uses a multi-attribute choice experimental approach to quantify the various characteristics of the stalking experience to determine the value that amateur stalkers attach to the stag numbers, the landscape and other attibutes. Unlike previous applications of stated preference, a large proportion (one-third) of a full factorial design is used to present stalkers with different alternative stalking packages within a postal survey. The results indicate a way forward that could be agreeable to both deer managers and conservationists. 相似文献
62.
ABSTRACTContemporary smart cities have largely mirrored the sustainable development agenda by embracing an ecological modernisation approach to urban development. There is a strong focus on stimulating economic activity and environmental protection with little emphasis on social equity and the human experience. The health and well-being agenda has potential to shift the focus of smart cities to centre on social aims. Through the systematic and widespread application of technologies such as wearable health monitors, the creation of open data platforms for health parameters, and the development of virtual communication between patients and health professionals, the smart city can serve as a means to improve the lives of urban residents. In this article, we present a case study of smart health in Kashiwanoha Smart City in Japan. We explore how the pursuit of greater health and well-being has stretched smart city activities beyond technological innovation to directly impact resident lifestyles and become more socially relevant. Smart health strategies examined include a combination of experiments in monitoring and visualisation, education through information provision, and enticement for behavioural change. Findings suggest that smart cities have great potential to be designed and executed to tackle social problems and realise more sustainable, equitable and liveable cities. 相似文献
63.
Sardini P Robinet JC Siitari-Kauppi M Delay F Hellmuth KH 《Journal of contaminant hydrology》2007,93(1-4):21-37
An out-diffusion laboratory experiment using a non-reactive tracer was fitted using the Time Domain Diffusion (TDD) method. This rapid particle tracking method allows simulation of the heterogeneous diffusion based on pore-scale images and local values of diffusivities. The superimposed porosity and mineral 2D maps act as computation grids to condition diffusion pathways. We focused on a Palmottu granite sample, in which the connected pore space has a composite microstructure with cracks linking microporous minerals and is above the percolation threshold. Three main results were achieved: (i) When compared to the fitting obtained with one coefficient (best mean square residual R = 1.6 x 10(-2)), diffusion is shown to be suitably characterised with two coefficients related to cracks and microporous minerals (best R = 6.5 x 10(-4)), (ii) rather than imposing a local apparent diffusion coefficient D(a) independent of the local porosity Phi, a best fit is obtained by applying Archie's relationship D(a) = D(0) x G with G = Phi(m) to each pixel of the calculation grids (G is the geometry factor, D(0) is the diffusion coefficient in free fluid, and m is Archie's exponent), and (iii) the order of magnitude of the fitted diffusion coefficient or Archie's exponents (m=0 for microcracks and m=1.82 for microporous minerals) is physically realistic. 相似文献
64.
Zisheng Xing Charles P.-A. Bourque Fan-Rui Meng Roger M. Cox D. Edwin Swift Tianshan Zha Lien Chow 《Ecological modelling》2008
In this paper we present a simple hybrid gap-filling model (GFM) designed with a minimum number of parameters necessary to capture the ecological processes important for filling medium-to-large gaps in Flux data. As the model is process-based, the model has potential to be used in filling large gaps exhibiting a broad range of micro-meteorological and site conditions. The GFM performance was evaluated using “Punch hole” and extrapolation experiments based on data collected in west-central New Brunswick. These experiments indicated that the GFM is able to provide acceptable results (r2 > 0.80) when >500 data points are used in model parameterization. The GFM was shown to address daytime evolution of NEP reasonably well for a wide range of weather and site conditions. An analysis of residuals indicated that for the most part no obvious trends were evident; although a slight bias was detected in NEP with soil temperature. To explore the portability of the GFM across ecosystem types, a transcontinental validation was conducted using NEP and ancillary data from seven ecosystems along a north-south transect (i.e., temperature–moisture gradient) from northern Europe (Finland) to the Middle East (Israel). The GFM was shown to explain over 75% of the variability in NEP measured at most ecosystems, which strongly suggests that the GFM maybe successfully applied to forest ecosystems outside Canada. 相似文献
65.
Experiments on mixing and dissipation in internal solitary waves over two triangular obstacles 总被引:2,自引:1,他引:1
Chen-Yuan Chen John R.-C. Hsu Ming-Hung Cheng Cheng-Wu Chen 《Environmental Fluid Mechanics》2008,8(3):199-214
A series of laboratory experiments was undertaken in a stratified two-layer fluid to investigate the energetics of the interaction
between an internal solitary wave (ISW) and triangular obstacles, as well as to determine the partitioning of ISW energy and
its subsequent dynamics. The ISW energy was dissipated as a result of internal breaking and turbulent mixing induced by wave
instability. Tests involving different combinations of triangular obstacles in various heights and intervals and ISW of different
amplitudes were performed. The wave features resulting from the interaction of an ISW and double obstacles were found to differ
from those of single obstacle. The incident energy of an ISW was either reflecting back from the obstacles, dissipated through
turbulent mixing, or transmitted over the double obstacles. Reduction in wave energy increased as the intervals between obstacles
reduced. For two obstacles in different heights, energy dissipation was greater in the case with a higher obstacle ahead of
a lower one. However, the overall performance was dependent on the relative height of the obstacles, relative water depth
of the upper and bottom layer, in addition to the intervals between the obstacles. 相似文献
66.
围隔实验中浒苔在不同营养盐条件下的生长比较 总被引:2,自引:1,他引:1
近年来浒苔在我国黄海海区大规模暴发,给沿海海区造成了严重的环境问题.为了探究营养盐对浒苔生长的影响,2012年5月在黄海海区进行了现场船基围隔实验.实验共设置12个围隔装置,9种不同的营养盐条件.实验发现,浒苔对营养盐有极强的吸收能力,生长能力很强,在营养盐适中时,相对生长率最高可达82%,即使在低营养盐条件下也会保持10%左右的生长速率.在磷酸盐含量适中时,高浓度的硝酸盐更能促进浒苔的生长;充足、连续的营养盐补充是浒苔绿潮暴发的物质基础.通过浒苔吸收的营养盐含量估算其光合作用产生有机物的质量,发现与浒苔湿重增加量有着良好的线性关系. 相似文献
67.
T. J. Bergman J. C. Beehner D. L. Cheney R. M. Seyfarth P. L. Whitten 《Behavioral ecology and sociobiology》2006,59(4):480-489
To date, research on testosterone and behavior has focused on individuals, even when studying social behaviors that necessarily
involve multiple participants. Here, we explore male responses to other males of different dominance ranks and testosterone
levels in a population of wild baboons. In chacma baboons (Papio hamadryas ursinus) of the Okavango Delta, a male’s testosterone is related to his rank trajectory and, therefore, the threat he poses to other
males. To examine the effects of testosterone and rank on male–male interactions, we used playback experiments to measure
how a target male responded to the simulated approach of another male, scoring responses by whether or not the subject moved
away from the speaker in the first minute. High testosterone subjects did not move away from the speaker more often than low
testosterone subjects, but high testosterone callers elicited a move more often than low testosterone callers. When the combined
testosterone of the subject and caller was high, moves were most common. The rank relationship between subject and caller
did not predict moves, but the effect of combined testosterone on moving was most pronounced in adjacently ranked males. Adjacently
ranked, high testosterone males are the most likely to be competing for each others’ rank, and our experiments on these dyads
elicited the most moves. Both behavioral and experimental observations indicate that testosterone may be more important than
the rank relationship in predicting the outcome of male–male interactions. Furthermore, combined information on the testosterone
of both males was the best predictor of results, highlighting the utility of dyadic analyses when relating testosterone to
behavior. 相似文献
68.
有机化学实验教学中的污染控制 总被引:1,自引:0,他引:1
基础化学实验涉及学科专业门类多,实验排放大量的各种各样的污染物,大多没有进行处理就直接排放,针对目前现状,论述有机化学实验教学中污染控制的重要性,通过采用性质实验压缩化、经典合成小量化、实验资源循环化手段,充分发挥学生的主体作用,培养学生的创新能力,逐步减少有机实验污巢,实现有机实验绿色化的设想。 相似文献
69.
通过室内模拟实验,研究了典型有机污染物[乙醇、丙酮、尿素(ON)和多灭磷(OP)]对海水pH和二氧化碳体系的影响.结果表明,t=7 d时,低浓度的醇和酮(<0.5 mmol·L-1)促进生物固碳体系生长,相应水体中的pH值升高,而DIC、HCO-3和p(CO2)与对照组相比都明显下降(p<0.01);引起DIC、HCO-3及p(CO2)下降幅度最大的醇和酮浓度分别为0.25 mmol·L-1和0.1 mmol·L-1. 当醇、酮达到一定浓度后,藻类固碳能力开始下降,甚至分解并转化为无机碳,从而引起DIC、HCO-3和p(CO2)含量的升高及pH值的下降.实验设计范围内的ON和OP添加组中,上述二氧化碳体系各组分含量与其初始值相比,均呈现负变化,即对应水体中DIC、HCO-3和p(CO2)均在降低.t=7 d时, 4种典型有机污染物影响下的DIC变化幅度(ΔDIC)与相应水体中孔石莼干重变化量(Δm)呈现显著负相关(p<0.01或p<0.05),相关系数分别为:-0.902、 -0.945、 -0.898和-0.918.造成以上差异的原因与生物固碳体系在不同种类不同浓度有机污染作用下对海水二氧化碳利用性不同有关. 相似文献
70.
In this study, the surface chemical functional groups of Bacillus cereus biomass were identified by Fourier transform infrared (FTIR) analytical technique. It had been shown that the B. cereus cells mainly contained carboxyl, hydroxyl, phosphate, amino and amide functional groups. The potentiometric titration was conducted to explain the surface acid-base properties of aqueous B. cereus biomass. The computer program FITEQL 4.0 was used to perform the model calculations. The optimization results indicated that three sitesthree pKas model, which assumed the cell surface to have three distinct types of surface organic functional groups based on the IR analysis results, simulated the experimental results very well. Moreover, batch adsorption experiments were performed to investigate biosorption behavior of Cu(Ⅱ) and Pb(Ⅱ) ions onto the biomass. Obviously, the adsorption equilibrium data for the two ions were reasonably described by typical Langmuir isotherm. 相似文献