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The evaluation of natural ventilation potential for effective sustainable options and innovative green building design strategies is of great interest to architects, researchers and governments. From a retrospective review, we found that the potential evaluation of natural ventilation (NV) cooling effectiveness in the same category based on similar meteorological uncertainty, research objectives and objects showed significant differences. Uncertainties added and uncertainty propagation (both model form uncertainties and parameter uncertainties) could result in large discrepancies between simulation outcomes and real scenarios, especially in the design performance modeling (DPM) phase. In this conceptual design stage, a few parameters are available and therefore decisive. It is necessary to review and identify the key performance indicators and explore the extent to which deviations are caused by inconsistencies or biases in model information. As a basis for more concrete research, we propose statistical tests based on quantitative evaluations to explore the rule of natural ventilation potential volatility and identify whether there is a significant potential improvement resulting from the critical parameter enhancement with the optimal relationship. The showcase is applied in China, where there has been a significant amount of criticism regarding the current building climate zoning due to the perceived coarseness of the system and where there has been an active exploration into the possibility of redefining building climate zoning with a view toward improving its accuracy and effectiveness. [ABSTRACT FROM AUTHOR]

Thermal comfort is of growing interest to academics and practitioners, while the quality of open urban spaces has received increasing attention in developed countries. Rapid urbanization has led to environmental problems, but there is relatively little research that brings these two areas together to address how microclimatic conditions influence quality of urban life. In this study, based in the high-density and high-rise Lujiazui district of Shanghai, an outdoor thermal comfort questionnaire survey was combined with meteorological data to assess pedestrian psychological, physiological and behavioral reactions to outdoor urban spaces. The research, conducted during the coldest months of the year, found that most respondents were thermally comfortable at the time of the survey and were also satisfied with the outdoor thermal environment in Lujiazui. By correlating micrometeorological and questionnaire survey data, research analysis established local thermal comfort criteria based on air temperature, global radiation, air humidity and wind velocity. The findings of this research enhance our understanding of human thermal comfort. In addition, the correlation of meteorological and social data contributes to our understanding of thermal comfort parameters in urban outdoor spaces and can contribute to more pedestrian-friendly urban planning. [ABSTRACT FROM AUTHOR]

Assessing the effect of thinning of overstorey trees and planting of native trees will be helpful to better understand the vegetation restoration. A stand conversion experiment was conducted in a 12-year-old Acacia auriculiformis plantation in 1996. Treatments were thinning and underplanting, underplanting, thinning, and control. Results showed that thinning enhanced the establishment and growth of underplanted and regenerated native seedlings. The thinning and underplanting treatment reduced soil organic matter, soil total nitrogen, soil bulk density and soil water content but increased soil phosphorus and potassium contents. The establishment and growth of underplanted native species depended on their responses to light and soil resources. Thinning increased recolonisation by native species. Since some of the underplanted native trees grow rapidly, the regenerating canopy cover can become dense after thinning, and the density of the new canopy inhibits regeneration of other native tree species. Therefore, moderate thinning should be periodically performed as part of the long-term management of plantation and different thinning intensities can be used to increase spatial variability in the overstorey. The shade tolerance of native species was the most important characteristic in determining the response of the native trees to the treatments. [ABSTRACT FROM AUTHOR]

Due to its reliability, simple and portable structure and low costs,the passive sampler is the ideal measuring device for developing countries. In spite of this, there has been no reporting on its reliability in extremely low temperate areas such as those associated with Northeastern China. The measuring of SO2 by passive samplerswas attempted at extremely low temperatures in the heavy industrialized area of Shenyang, China from December 25 to 28, 1995. The measurements associated with the passive sampler were accompanied by reference analysis utilizing conventional gas bubble sampling. The calibration equation generated from the parallel tests for the passive samplerat an extremely low temperature was 100 W 265 W WSO2/t (-11 ~-4 deg. C, ppb). The annual average concentration of SO2, as sampled by the passive sampler, was 79ppb, 33 ppb, and 24ppb in heavily polluted, intermediate and reference areas, respectively. The multi-regressional analysis applied to data collected during the mornings (6:00 am - 8:00 pm), afternoons (11:00 am - 1:00 pm) and night (10:00 pm - 12:00 pm) shows that SO2 concentrations in the morning and night were the most significant variables associated with daily concentration averages. [ABSTRACT FROM AUTHOR]

A study was carried out on degraded hilly land in South China to reveal the interspecific relationships between the shrub Rhodomyrtus tomentosa and four target tree species over time. The 3-year experiment showed that the shrub selectively improved or inhibited seedling growth. The photosynthetic performances of target tree species were altered by the nursing effect of the shrub in terms of photosynthesis--light response curves and showed maximum photosynthetic rates and stomatal conductance. Shrub interactions with all the target tree species were commensal (+0, for target and shrub) in year 1 but maintained or changed to amensal (-0) or antagonism (+-) along with the ontogenesis of different target tree species. The poor growth of Pinus elliottii and Michelia macclurei seedlings in the presence of the shrub indicated that they had lower potential to become forest restoration target tree species. In contrast, Schima superba was facilitated by the shrub in years 1-3 and inhibited the shrub in year 3, indicating that it had substantial potential to replace shrubs and trigger reforestation. sSelection and silvicultural techniques of target tree species were both important in forest restoration. [ABSTRACT FROM AUTHOR]