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41.
自然保护地不仅对保护生物多样性具有重要意义,也在减缓气候变化、实现碳中和目标方面起到关键作用。中国自然保护地的碳中和贡献尚未得到充分的认识和关注,相关研究尚处于起步阶段。首先对中国陆域自然保护地的碳储量、碳吸收能力、人为碳排放水平展开初步评估,发现陆域自然保护地在保护高碳中和贡献生态系统方面存在不足。随后提出了中国自然保护地碳中和贡献研究的3个关键课题,分别是自然保护地碳循环作用机理研究、自然保护地碳中和贡献评估与管理、生物多样性保护和碳中和的协同治理。最后围绕关键课题提出14个具体研究问题,为中国自然保护地减缓气候变化的科学研究与管理实践构建系统框架。  相似文献   
42.
This study investigates the response of water resources regarding the climate and land‐cover changes in a humid subtropical watershed during the period 1970–2009. A 0.7°C increase in temperature and a 16.3% increase in precipitation were observed. Temperature had a lower increase trend, and precipitation showed definite increasing trend compared to previous studies. The main trend of land‐cover change was conversion of vegetation and barren lands to developed and crop lands affected by human intervention, and forest and grass to bush/shrub which considered to be caused by natural climate system. Hydrologic responses to climate and land‐cover changes resulted in increases of surface run‐off (15.0%), soil water content (2.7%), evapotranspiration (20.1%) and a decrease in groundwater discharge (9.2%). We found that surface run‐off is relatively stable with precipitation, whereas groundwater discharge and soil water content are sensitive to changes in land cover, especially land cover brought about by human intervention.  相似文献   
43.
Atmospheric circulation generally influences regional climate variability and thereby controls catchment hydrology and consequently transport of elements in natural riverine systems. This study examined dependencies between total organic carbon (TOC) variability in the River Oulujoki (Finland) during 1963–2011 and prominent atmospheric circulation patterns (ACPs), which manifest natural climatic conditions over Finland and control hydrological processes in the river catchment. North Atlantic Oscillation, Scandinavia, East Atlantic and East Atlantic/West Russia patterns were statistically significant ACPs affecting variations in TOC export at River Oulujoki lower basin area. In the River Oulujoki, TOC export was largely controlled by changes in TOC fluxes generated from tributaries of river and near areas to its main channel. Besides, runoff from Lake Oulujärvi slightly influenced TOC export variability in the River Oulujoki. Understanding such responses of TOC fluxes to ACPs is a useful tool for sustainable water resources planning and management on regional and local scales.  相似文献   
44.
We present a life cycle analysis of a lightweight design of high concentration photovoltaic module. The materials and processes used in construction are considered to assess the total environmental impact of the module construction in terms of the cumulative energy demand and embodied greenhouse gas emissions, which were found to be 355.3 MJ and 27.9 kgCO2eq respectively. We consider six potential deployment locations and the system energy payback times are calculated to be 0.22–0.33 years whilst the greenhouse gas payback times are 0.29–0.88 years. The emission intensities over the lifetimes of the systems are found to be 6.5–9.8 g CO2eq/kWh, lower than those of other HCPV, PV and CSP technologies in similar locations. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
45.
Char particles from pyrolyzed biomass vary in particle size and shape. On average, the particles are more elongated the larger their size. The average size‐specific elongation is almost alike for all investigated samples, i.e. independent from their source material and process. The particle collectives cannot be characterized accurately with classical particle size distributions, which assume spherical particle shape. Accounting for their shape, they can be described more accurately with particle size distributions that are based on an ellipsoid model. The high bulk porosity is mainly attributed to the spaces between particles.  相似文献   
46.
In spite of its great importance for the dry classification of fine powders, the processes in deflector wheel classifiers are to a large extent unknown. Therefore, in the present work a commercial available classifier was modified to gain an optical access to the deflector wheel. For the first time, the obtained photographs enable an observation of the gas flow and the particle motion between the blades of the deflector wheel. Especially the importance of particle‐particle‐ and particle‐blade‐collisions could be shown.  相似文献   
47.
This paper quantifies the influence of Al2O3 nanoparticles on the pool boiling performance of R134a/polyolester mixtures on a Turbo-BII-HP boiling surface. Nanolubricants with 10 nm diameter Al2O3 nanoparticles of various volume fractions (1.6%, 2.3%, and 5.1%) in the base polyolester lubricant were mixed with R134a at two different mass fractions (0.5% and 1%). The study showed that nanolubricants can improve R134a boiling on a reentrant cavity surface as long as the nanoparticles remain well dispersed in the lubricant and are at sufficiently large concentration. For example, three of the refrigerant/nanolubricant mixtures with the smallest nanoparticle mass fraction exhibited average enhancements over the entire heat flux range of approximately 10%. However, when the nanoparticle mass fraction was increased to a point that likely encouraged agglomeration, an average heat transfer degradation of approximately 14% resulted. An existing model was used to predict the boiling heat transfer.  相似文献   
48.
49.
王静  杜鹏  吴中平 《南方建筑》2021,(2):96-102
揭示湿热气候下高层办公楼气候适应性设计策略与应用逻辑,为我国高层办公楼的绿色设计提供借鉴与参考。运用建筑气候适应性思想,聚焦方案设计阶段,通过案例归纳与分析气候特征,总结湿热气候下绿色高层办公楼在隔热、遮阳、通风、节能方面的设计策略。并通过广东交通设计大厦项目实践,在城市、建筑与细部尺度将气候适应性设计策略有效运用,深刻塑造了建筑的形体与空间特色。高层办公楼气候适应性设计,有益于创造出适应气候环境、更加节能健康的绿色建筑。  相似文献   
50.
孙泽宇  代鹏飞  翟俊 《中国园林》2021,37(4):122-126
全球气候变化威胁着本就脆弱的城市生态系统。探索具有气候适应性的植物配置方法,是应对气候变化、保护城市生物多样性和稳定城市生态系统的有效手段。介绍一种能够在气候变化大背景下持续稳定地提供生态系统服务的适应性城市植物配置方法。以苏南地区为例,首先对植物材料的物种特性与适应性进行研究与编码,再根据植物群落的抵抗力稳定性、结构多样性以及场所审美文化和成本因素的综合考虑进行配置。为城市植物群落应对气候变化,提升城市植物群落的生态系统服务功能提供新思路。  相似文献   
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