Desertification and Re-Afforestation of the Coastal Land in Changjiang County, Hainan Island

来源 :Chinese Journal of Geochemistry | 被引量 : 0次 | 上传用户:hao8035
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Changjiang County is located to the northwest of the tailing range of the Wuzhi Mountains on Hainan Island, facing the sea and being against the Mountains. From southeast to northwest, it gradually descends in relief from mountain, hill, tableland, terrace to coastal plain. Its sandy coastal line is measured at 44.85 km in length and its rocky coastal line at 7.15 km along the county. The desertified coastal land covers an area of about 61.15 km 2 , extending from hundreds of meters to 3 km in width, of which the active sand land accounts for 5.333 km 2 and the semi-active sand land, 7.333 km 2. The dunes are developed at the rate of 10-30 m per year from the seashore toward the hinterland. The Forest Departments of Hainan Province and Changjiang County have done a series of sand-control experiments. The chief technological measures are as follows: (1) to stabilize the drift sand first to create an adequate condition for afforestation; (2) to plant the big and strong saplings of Casuarin equisetifolia with nutrient bags in deep pits; and (3) to apply new techniques in “dry-season planting” to guarantee the quality of afforestation. The above experiments were successful. However, there still exist some problems such as quite seriously wilting shoot, lower survival rate of Pandanus tectorius in the vertical lines to the usual wind direction, monotonous tree species in afforestation and subsequent poor management. Thus some suggestions are offered in this paper for future extension: (1) to apply REE fertilizers in the process of afforestation to increase the resistance of the plants; (2) to increase the vertical lines of Pandanus tectorius to the usual wind direction to raise their survival rate in the network of sand stabilization; (3) to enlarge the area of liana planting to enhance the stability of sand; (4) to try to introduce new tree species from other regions, which are of good performance in sand stabilization; (5) to interplant the adaptable economic crops; and (6) to make more investments and better management and conduct more extensive environmental education to ensure the early accomplishment of the protection forest belt around the island. Changjiang County is located to the northwest of the tailing range of the Wuzhi Mountains on Hainan Island, facing the sea and being against the Mountains. From southeast to northwest, it gradually descends in relief from mountain, hill, tableland, terrace to coastal plain. Its sandy coastal line is measured at 44.85 km in length and its rocky coastal line at 7.15 km along the county. The desertified coastal land covers an area of ​​about 61.15 km 2, extending from hundreds of meters to 3 km in width, of which the the active sand land accounts for 5.333 km 2 and the semi-active sand land, 7.333 km 2. The dunes are developed at the rate of 10-30 m per year from the seashore toward the hinterland. The Forest Departments of Hainan Province and Changjiang County have done a series of sand-control experiments. The chief technological measures are as follows: (1) to stabilize the drift sand first to create an adequate condition for afforestation; (2) to plant the big and strong s aplings of Casuarin equisetifolia with nutrient bags in deep pits; and (3) to apply new techniques in “dry-season planting ” to guarantee the quality of afforestation. However, there still exist some problems such as as quite seriously wilting shoot, lower survival rate of Pandanus tectorius in the vertical lines to the usual wind direction, monotonous tree species in afforestation and subsequent poor management. Thus some suggestions are offered in this paper for future extension: (1) to apply REE fertilizers in the process of afforestation to increase the resistance of the plants; (2) to increase the vertical lines of Pandanus tectorius to the usual wind direction to raise their survival rate in the network of sand stabilization; (3) to enlarge the area of ​​liana planting to enhance the stability of sand; (4) to try to introduce new tree species from other regions, which are of good performance in sand stabilization; (5) to interplant the adaptable economic crops; and (6) to make more investments and better management and conduct more extensive environmental education to ensure the early accomplishment of the protection forest belt around the island.
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