Stufy On Loe-Carbon Green Technology Of Highway

Global warming and its harm serious impact on economic and social sustainable development, reduce emissions of greenhouse gases such as carbon dioxide without delay. Transportation as one of the main carbon emissions source, is the important control link of Greenhouse gas emissions, climate change mitigation. It provide a viable way for low-carbon transport green plants that absorb carbon dioxide and give off oxygen by photosynthesis. One of the most important functions of plants is carbon fixation and oxygen release through photosynthesis, by absorbing CO2from the air to mitigate the greenhouse effect in a certain extent. In this paper, the common21kinds of green plants in South highway were determined and analyzed and compared selected to provide a theoretical basis for low-carbon green highway. Li-6400portable photosynthesis system, was used to test the diurnal variations of photosynthetic rate and stomatal conductance of evergreen plants in Southern Highway, and to calculate their ability of absorbing carbon dioxide and releasing oxygen and to calculate the transpiring water volume and absorbing heat quantity of plants. On this basis, investigated the effect of environmental factors on plants absorb carbon dioxide and compared dust-deposition, chlorophyll content and organic acid content of different plants. Correlation of carbon-fixing, oxygen-releasing, temperature-reducing and humidity-increasing with dust-deposition, chlorophyll content and organic acid content, and net photosynthetic rate with air pollutants were analyzed. Finally, economic comparison were conduct on plants. Thesis results provide a scientific basis for highway tree species selection and configuration.The results showed that: 1) Net photosynthetic rate of deciduous plants was significantly higher than evergreen plants. Canna glauca L.(Isolation), Koelreuteria bipinnata Franch(Slope bottom) and Prunus ceraifera cv. Pissardii (Slope bottom) had better carbon-fixing and oxygen-releasing effects, while Trifolium(Slope), Trachycarpus fortunei(Slope bottom) and Radix Ophiopogonis(Slope) had worse carbon-fixing and oxygen-releasing effects. The average carbon fixation and oxygen release of deciduous plants in per unit leaf area is higher than evergreen plants. Prunus ceraifera cv. Pissardii, Canna glauca L. and Koelreuteria bipinnata Franch had higher cooling and humidification ability, while Trifolium, Trachycarpus fortunei and Trifolium did not act as well as them. The average transpiring water volume and absorbing heat quantity of deciduous plants in per unit leaf area are higher than evergreen plants.2) Soil microbial communities’DNA sequence richness, diversity and Shannon-Weaver index were improved of highway soil samples in the coexistence of different nitrogen content and heavy metals. Plants have certain elimination function to heavy metals, and nitrogen deposition is contribute to the removal of heavy metals by plants. Heavy metals and nitrogen deposition in soil have influence on the rate of net photosynthesis of plants. Heavy metals reduce the rate of net photosynthesis of plants, and nitrogen helps plants to increasing the net photosynthetic rate.3) The average dust removal ability of evergreen plants than deciduous plants, but the average content of chlorophyll less than deciduous plants. Addition of pyruvic, the other three kinds of organic acids (oxalacetic acid, glyoxylic acid, a-ketoglutaric acid) content in deciduous plants were higher than the evergreen plants. Carbon fixation and oxygen release and cooling and humidification have a higher positive correlation(r=13, p=0.756). Carbon fixation and oxygen release with chlorophyll, dust catching quantity, glyoxylic acid content have a positive correlation, and a negative correlation with the content of oxalacetic acid.4) According to a comprehensive release of oxygen and carbon sequestration capacity, cooling and humidification and economic considerations, the highway greening plant selection is that isolation belt plants:Canna-glauca L., Aucuba japonica var.variegata D’Om-Brain, Photinia glabra; slope plant:Radix Ophiopogonis, Euonymus fortunei Hand.-Mazz, Hedera helix; slope bottom plant:Nerium indicum Mill., Camellia japoica, Jasminum mesnyi Hance, Koelreuteria bipinnata Franch, Prunus ceraifera cv. Pissardii, magnolia grandiflora-linn。...