| Aeolian desertification is one of the hottest issues in the study of the sharp decline of global land resources,land productivity degradation and ecological environment deterioration,and it is also an extremely severe environmental and social problem that China is facing currently.The site classification for the purpose of laeolian control can provide a guarantee for the scientificity and rationality of precise desertification controlling measurements.The study took the Hulunbeier sandy area(New Barag left banner,New Barag right banner,Hailar,Ewenki autonomous banner and Chen Barag banner)as the case study area.Based on the theory of climatology,geological geomorphology,botany,and ecology,both field surveys and remote sensing interpretation were used to classify the site types.Then,aeolian desertification control measurements were proposed according to the characteristics of different site types.The results showed that:ยท(1)The Hulunbeier Sandy land was divided into two site regions(middle-temperate semi-arid region of Hulunbeier plateau and middle-temperate semi-humid region of Hulunbeier plateau)according to annual aridity index,six site groups(sand site group in middle-temperate semi-arid region of Hulunbeier plateau,plain site group in middle-temperate semi-arid region of Hulunbeier plateau,river valley site group in middle-temperate semi-arid region of Hulunbeier plateau,sand site group in middle-temperate semi-humid region of Hulunbeier plateau,plain site group in middle-temperate semi-humid region of Hulunbeier plateau and river valley site group in middle-temperate semi-humid region of Hulunbeier plateau)according to landform and eighteen site types according to vegetation coverage,irrigation and salinization degree.(2)The area and distribution of Hulunbeier sandy land were acquired.The area was 6369.13km2,which was distributed in the upper,middle and lower sand belts:The first sand belt starts from Uleguede in Ewenki in the north,reached Baronghanda Gayin Maode in the south,and faced the Daxinganling mountains in the east.The second sand belt was located on both sides of Yimin River and the Sinai River.It started from the 12th team of Hailar Sheltala Ranch in the north and ended at Bayanyu Forest Station in the south.The third sand belt is distributed along the south bank of Hailar River,starting from the east bank of Hulun lake in the west,and reaching the west mountain of hailar in the east.(3)The site classification map of Hulunbeier sandy area were obtained.According to the sant site type groups,the aeolian controlling methods combining engineering measures and plant measures like rotational husbandry management,scorpion pine forest enclosure,Pinus sylvestris var.mongolica seedling afforestation,irrigation and grass mixing,mechanical sand barriers,construction of revetment forest were proposed.The aeolian controlling method for controlling the stocking capacity and vegetation construction like airline seeding afforestation,setting shrub live sand barrier,returning farmland to forest,conservation tillage,setting up farmland shelterbelt,establishing management and protection station,and sealing management ware proposed for the plain type groups;The vegetation restoration and sand control method like construction of revetment forests and water conservation forests,planting of salt-tolerant plants,laying of salt-resistant alkali materials were proposed for the river valley type groups.Further detailed layout of the corresponding land desertification control measures for each site type.The study provided accurate and intuitional scientific basis for aeolian desertification controlling work in study area and theoretical references for the method of site type classification for aeolian desertification control in sandy area in China. |
