| The paper is aimed to expound the site condition, the movement regularity of water and salinity, the fitness of experimental trees and the relation of site condition and crop tree growth in the seawall in Lianyungang of Jiangsu Province. After analyzing these observed data, the results can provide scientific reference for building inshore shelter forest and greening seawall. The results as followers are got: (1)The soil of seawall slope was clay loam which was from medium to intense salinized soil. Its soil bulk density and porosity had adapted to most plant growth; the average content of organic matter was 21.84% in 020cm soil and that was 7.45% in subsoil; the range of pH value was from 7.04 to 8.93 and the conductivity was from 0.10284 to 0.86956mS/cm in 100cm soil; the water content was higher in March and September, lower in June in medial and upper slope and it was near to the blighting coefficient, but it was higher in subsoil. It was so important to water the seawall trees properly or prevent the evaporation that the seawall trees could normally grow. (2)Among all factors of the seawall site condition, the sea wind and the sea fog were very important. The sea fog and the wind, especially the strong wind, were frequently occurred in experimental field. Because there were few trees and the sea fog settled slowly and its inbreak distance was long, the conductivity of 20ml absorption liquid which contained 1m3 air was about from 10 to 12μS/cm near the seawall and it was about from 6 to 8μS/cm in 1000m. The falling was no more than 50%. The conductivity of the absorption liquid has indicated that the air salt content was higher near the seawall from March to August and it was lower from September to December, which was relation to wind direction and atmospheric humidity. (3)The movement regularity of the seawall water and salinity was obvious. On the basis of the inner slope, the range of subsoil water depth was from 0.26 to 0.8m. The minimum was in August and the maximum was from November to March, but between June and July it was larger. The mineralized degree was consilient with the ground water table. It was smaller in July and August and September and in the other was larger. The range of the conductivity was from 2.026 to 5.888mS/cm. The salinity movement had desalination and accumulative salinity. The accumulative salinity in surface layer was severe in March and April. (4)Many factors affected the salinity content of the seawall soil. Among them, the obvious factors were water content(x1), the distance of superficial soil and subsoil water(x3) and the conductivity of subsoil water(x4). With the help of data, many regression models were laid. ①The relation of the mineralized degree of subsoil water and the conductivity: y = 0.7069x + 0.439; ②the relation of the salt content and the conductivity: y0=0.35345x+0.2195; ③the relation of the seawall soil conductivity and the water content and the distance of superficial soil and subsoil water and the conductivity of subsoil water: y1=-0.93207+0.03807x1-0.53704x3+0.24221x4; ④the relation of the salt content of seawall soil and the water content and the distance of superficial soil and subsoil water and the conductivity of subsoil water: y2=-0.10994+0.013075x1-0.189817x3+0.085609x4. (5)The seawall site condition was fit for few species of trees growth. Seeing the soil condition, trees were more in middle and upper slope than downgrade, but from all site factors, the fit trees were limit in the all seawall. Trees should be opted for drought resistant and salt resistant and wind resistant. According to the seawall soil characteristics, the changed measure should be choosed to improvement soil and in this basis to build experimental demonstration woods. The experimental trees had different characteristics of accepted stress and adaptability. Among them, the sea fog and the sea wind were obvious. Different trees had different adaptability. The proper extent of fit trees upon the seawall environment in September was in turn: Golden Bell>Hybrid osier>Amorpha>Black locust>Chinaberry.
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