Research On Plants' Ecological Adaptability In Ninghuai Expressway

Ecological adaptability of afforestation plants in expressway is directly related to the exertion of landscape value, ecological and environmental protection function of afforestation project. In addition, it is very important to restore road region ecosystem and improve ecological environment. This paper chooses afforestation plants in Ninghuai expressway as the research objects and studies site condition in every section of expressway, especially soil property, physiological and biochemical reaction of plants' adaptability to arid adverse circumstances as well as ecological adaptability of present plants. The following results are indicated.(1)The soil in tested field is all loam. Silt content in Nanjing region is relatively high and glue granule content in Huaian region is higher. Sand content in North Huaian is comparatively high, but its ability to conserve water and fertility is poor, which will cause the loss of water and soil. The soil unit weight and opening degree are moderate. The average pH value in the soil is 8.22～1.80, which are all moderate alkaline soil. The organism content is 2.02～4.04 g/kg, a bit lower than the local average level. Entire nitrogen content in the soil is 218.48～502.21 mg/kg, a bit lower than the local average level. Its quick-acting phosphorus content is 33.80～50.29 mg/kg, which has satisfied the requirements for plants to grow. The content of quick-acting potassium is 50.16～330.82 mg/kg, while that in Nanjing region is lower, about 50.16 mg/kg.(2)The whole physical and chemical character of soil in tested field is relatively poor, especially the pH value whose average value has reached 8.43 and which is the important factor to influence the growth of plants.(3)On the basis of analyzing the main physical and chemical character index of the soil, I conclude that soil unit weight and opening degree are altitude positive relationship and soil pH value and entire nitrogen contents are obvious negative relevance, while relevance among other soil factors is not obvious.(4)Judging from the whole, lamina moisture content of all kinds of plants is falling off from May to October. Compared with conductivity, chlorophyll contents, free proline, third dialdehyde, solubility candy contents tend to increase. There is great difference in plant physiological and biochemical index value in different months.(5)By means of related analysis on the main drought-resistant index of plants, I find that solubility candy, free proline and the third dialdehyde are well related, while other index relevance is not very obvious which needs to be analyzed and studied independently.(6)By means of analysis on the main components of drought-resistance index of the plants, this paper finds that the contribution of gene loading amounts adheres to the following order, that is solubility sugar＞malonaldehyde＞free proline＞relative moisture content＞chlorophyll content＞relative conductivity. It shows that the former three single indexes can better reflect plants' whole resistance to drought.(7)This paper adopts coordinate comprehensive evaluation and subordinate function of fuzzy mathematics. The results show that Nerium indicum and Photinia serrulata have better drought-resistance, followed by Lagerstroemia indica and Euonymus japonicus 'Aureomarginatus' and then come Prunus cerasifera 'Atropurpurea' and Acer palmatum 'A tropurpurea'.(8)The site condition in Ninghuai expressway is very bad, but the survival rate of the plants is high and the adaptability is relatively better. Formed tree has better adaptability than arbustum, while bamboo and lawn have better adaptability. The adaptability in mutual communication area is better than that in side ascent and arbustum as well as sod in side ascent has better adaptability.(9)The following arbors have better adaptability, such as Sophora japonica, Sapium sebiferum, Zelkova schneideriana, Celtis sinensi, Celtis sinensis, Ginkgo biloba, IIex cornuta Lindl, Magnolia grandiflora, Ligustrum lucidum, Firmiana simplex, Trachycarpus fortunei and Magnolia denudate. Arbustums which have better adaptability are Prunus mume, Acer palmatum 'Atropurpurea', Hibiscus syriacus, Prunus persicaAlropurpurea, Lagerstroemia indica, Nerium indicum, Chimonanthus praecox, Prunus persica, Photinia serrulata and Kerria japonica form. pleniflora。Bamboos are Phyllostachys glauca McClure and Phyllostachys bambusoides. There are three kinds of lawn which have better adaptability, that are Zoysia matrella, Cynodon dactylon and Trifolium repens.