Study On The Growth Status Of Haloxylon Ammodendron In Different Forest Ages In Gilantai Salt Lake

Gilantai Salt Lake is located in the southeast of Alxa Plateau,the area is dry with little rain and sandstorms,In order to realize the sustainable development of the salt lake,using Haloxylon ammodendron for afforestation is one of the important measures to control sand disasters and improve the ecological environment in this area.In this paper,Haloxylon ammodendron of different ages in Gilantai Salt Lake area was taken as the research object,and various growth characters of the forestation plant in the research area were investigated and studied by means of field investigation and sampling and laboratory test analysis.The characteristics of plant height,crown width,base diameter,above ground branch configuration,physiological characteristics of assimilated branch water,soil water change and other characteristics of Haloxylon ammodendron of different ages were analyzed and compared.The purpose is to understand the relationship between Haloxylon ammodendron and living environment,In order to further understand the population dynamics and ecological adaptability of Haloxylon ammodendron,to provide scientific basis for the protection and development of Haloxylon ammodendron plantation.The main research conclusions are as follows:(1)The plant height,base diameter,crown width and branch length of the two,five,10,15 and 30 years old Haloxylon ammodendron increased with the increase of the stand age,but the branch Angle did not change significantly,indicating that Haloxylon ammodendron has stronger population renewal ability with the increase of the stand age,and the carrying capacity between branches increased.Optimization of afforestation patterns in arid and semi-arid areas is beneficial to population regeneration.(2)The branch fractal dimensions of the five species were 1.7099,1.7111,2.5459,1.2933 and 2.1506,respectively.The increase of branch fractal dimension with the increase of age indicates that with the growth and development of Haloxylon ammodendron,the volume of crown and the number of leaves increase,and the branch pattern becomes more complex,so the utilization of space light resources is more effective.(3)The near-surface assimilated branches of Haloxylon ammodendron of low age were most susceptible to environmental impacts.The changes of water content and chlorophyll content in the assimilated branches of 30-year-old Haloxylon ammodendron were not obvious,indicating that the water distribution in the plants was uniform and the space utilization was more full.(4)The surface soil water content was low and easily evaporated,and the capillary roots of Haloxylon ammodendron were mainly distributed in the soil layer below20 cm.With the increase of the age of Haloxylon ammodendron,the ability of its roots to utilize deep water gradually increased.