Studies On Technology Models For Nursing And Restoration Of Desert Vegetation In The Outer Space Of Karamay Agricultural Comprehensive Developmental Region

Desert ecosystem is the material and ecological base of artificial oasis in Xinjiang. Desert vegetation acting as the ecotone between desert and oasis plays an absorbable and alleviatory role in threatening of desertification in the outer space of Karamay Agricultural Comprehensive Developmental Region. It is also the composition of the protective system of shelter-ecological security in the region. On the basis of former achievements on restoration of the degraded vegetation in arid land, this thesis develops five scientific and operational technology models for nursing and restoration of the desert vegetation based on the theory of restoration ecology. The thesis adopts the key technological experiment of nursing and restoration, aiming at special condition of desert site and degraded vegetation community, and provides accordingly technological support. Results as following: (1) Moisturizing can nurse desert vegetation when plant is short of water, growth is restrained, community vigor decrease because of drought stress, on the premise of conserving integral desert vegetation. Experiments of quota irrigation and season irrigation indicate that moisturizing 750m3/hm2 annually or irrigation in the end of autumn and the beginning of winter alleviate drought stress, achieve regeneration of dominate, improve community vigor and increase species abundance. (2) Rebuilding technology is used in restoring desert vegetation community when population regeneration gets worse and community structure and function degrades because of mankind disturbance and serious drought. Experiments reveal that using soil seed bank, seed flow, artificial seeding and simulating Tamarix spp. developing naturally can nurse and restore desert vegetation and improve desert ecological environment on the premise of supplying abandoned water of industry or agriculture. (3) Introducing moderately artificial plant into nature vegetation and controlling reasonably supplying water in large area of desert region can nurse desert vegetation whose community vigor decreases due to drought stress, on condition that intrinsic nature vegetation is integrated. Experiments reveal that vegetation merging technology not only increases increment of the desert vegetation, soil moisture and vegetation cover in merging area, but also brings certain spatial ecology effect and nurses desert vegetation in respondent area on the premise of promising survival of artificial plant. (4) Planting and seeding can restore and reconstruct vegetation in without irrigation region on condition that water is short in secondary bare land. Experiments show that Haloxylon spp. is suitable species in without irrigation region. The dimension of pit is 60cm×60cm×60cm and the depth of sand is 15cm as planting Haloxylon spp. If planting species is Tamarix spp. adopting planting method in the water storage container increases survival. At the same time, the improvement of micro-terrain by planting can provide emerged and resident condition of other plants and increase species abundance. Based on experiments above,the study integrate further the technology model for nursing of desert vegetation under the drought stress,the technology model for community rebuilding of degraded seriously desert vegetation,the technology model for combining desert vegetation with artificial plant,the technology model for restoration in without irrigation region and the technology model for restoration and reconstruction in secondary bare land .