Study on the Stability of Plantation for Wind Protection and Sand Fixation in Horqin Sandy Land
|School||Northeast Forestry University|
|Course||Soil and Water Conservation and Desertification Combating|
|Keywords||Horqin Sandy Land Sand-fixing forest Population structure Diversity Site quality Stability|
Horqin Sandy Land is one of China's major sand, due to the continued expansion of soil erosion and desertification, ecological conditions deteriorate further. Over the years the wind and sand, ecological restoration become the main objective of the afforestation research to create a large number of poplar, apricot, microphylla children, sorbifolia and Hedysarum different types of sand-fixing forest, and the stability of the plantation The issue has become the primary issue. In this paper, space instead of time methods start from the age structure of the population analysis, analysis of the different developmental stages of artificial solid sarin stability to the region's major wind solid sarin lobular golden pheasant children, sorbifolia and riding Lang object by population surface soil particle size statistical analysis, changes in the population structure, in particular made a detailed analysis of invasive species and community organizations in the community structure changes in different developmental stages, community each age class, species diversity measurement and comparison site quality change and population stability sexual comprehensive evaluation and then to measure the stability of the plantation community, to provide a theoretical basis for the sandy vegetation restoration and reconstruction. Conclusions are as follows: Based on comprehensive analysis of the Horqin three different artificial fixation forest soil particle size characteristics of the soil surface, can be more clearly drawn, three different populations of surface soil particle size differentiation is more obvious, showing a certain degree of regularity, that microphylla children cultural sorbifolia of sand paragraph With increased age class performance (1-0.05mm) particle size segment proportion gradually decreased, the proportion of coarse sand (1-0.25mm) gradually increased, while the fine sand ( 0.25-0.05mm) declining trend, Hedysarum population in accordance with the break in slope and the lower slope sequence also showed this law. Semi-fixed sand the (microphylla children, sorbifolia plots) the most crude and sorting better peak, followed by semi-mobile sand (Hedysarum plots), showing the stage of wind erosion and desertification. According to the characteristics of soil particle size distribution of wind erosion, draw different age classes microphylla children cultural sorbifolia surface soil sensitive particles sensitive to particle size segment share of erodible particle size of the relative value of the segment size performance of the microphylla children: Natural sand to gt ; 6a gt; 14a gt; 20a gt; 27a; sorbifolia: natural sand gt; 3a gt; 18a gt; 31a gt; 44a; Hedysarum: natural sand gt; break in the gt; slope gt; slope under think, to some extent, the area a wide range of sandstorm dust source material comes mainly from young woodland topsoil particles natural sandy and planting plantation growth vegetation less. The microphylla children artificial sand fixation have the ability to update, increase with age, the number of seedling growth is roughly equal to the number of adult death, to a certain extent reflected in the stable population. But as time goes on, the number of seedlings started to decrease was a type of recession, population structure, species diversity, a recession due to the decline in moisture, nutrients and other conditions, to develop to 27a. Comprehensive judgment, The microphylla children of 20 years artificial sand fixation best stability. Artificial solid sarin sorbifolia age class growth in the region with the decrease in the number of seedlings, large-diameter increase in the number of individuals, which shows poor the species of sorbifolia itself suckering ability, if not man-tending, due to temperature water site quality constraints, sorbifolia updates continuity is more difficult the overall crown above fruit species groups emerged in a recession population, the majority of individuals have passed reproductive age, the size of the population tends to reduce, but sorbifolia the plantation better stability, better adapted to the local environment, developed to 44a sorbifolia artificial sand fixation best stability. Hedysarum shrubs Horqin semi-mobile sand sand-fixing forest species, has a strong advantage in the quality and productivity of the stand, is a good drought-resistant species, as an important sand-fixing species, it play a significant role. The Hedysarum the stability by the different habitats in soil moisture, nutrient, lower slope Hedysarum population stability is better, Hedysarum population reflects the overall growth in population, there are many studies have shown that through the the Hedysarum plantation different habitat conditions: young individuals, species suckering ability is very strong, greater than the mortality rate of replenishment of the population continues to expand, the stability is gradually increased. Overall judgment result of the Hedysarum artificial slope solid sarin best stability. The final choice of three different species manual solid the Sarin most stable population in accordance with the method of the same species. Stability compared concluded: the 20a of artificial sand fixation microphylla children the best stability, 44a sorbifolia, followed by the lower slope of Hedysarum relatively poor. This shows that in Horqin sandy land planted three main types of artificial solid sarin, microphylla children and sand fixation stability characteristics of the species itself, the microphylla children plantation is quite able to adapt to the natural conditions of the region, at the same time play a sand-fixing role of the structure and function of their own communities to achieve a relatively stable state; the plantation overall of sorbifolia with the development and stability enhancement, but poor ability to update; also can come Hedysarum artificial Lin in the semi-mobile sand excellent adaptability, strong drought tolerance and suckering ability, has a strong role to play in the early recovery of the ecological environment, manual management is the area semi-mobile sand indispensable excellent species. The final for the microphylla children, sorbifolia and riding Lang three artificial sand fixation stability of draw for the Horqin sandy stable artificial solid sarin community should have the following conditions: (1) is adapted to local environmental conditions (2) outside interference has a certain resistance and recovery (3) with normal growth and development and self-renewal capacity (4) population structure.