| In this paper, by using of six different processing ways of plant such as contrasting, replacer soil or high densities, fertilization, water retaining agent, mulch and water retaining agent + mulch, we made the continuitly observing of planting of pure needle Cupressus duclouxiana forest and orchard,which are on Chen Jiazhai rocky desertification area of comprehensive control, and we made the study on the general trend of vegetation growth status under the different processing way. The results show that:the cypress growth conditions had been greatly improved and advanced under the different processing way, and the ecological benefit presented a gradually increasing trend; the growth status of planting of fruit samples was more complex because of the significantly difference in vegetation type, forest age,but this had a role in promoting of plant growth. The difference between the two samples is great:(1)Cupressus duclouxiana forest growth status and carbon fixation effect were significant, which had strong adaptability to the environment and the characteristics of frost tolerance and drought resistance. ①Tree height index: natural conditions under the tree height increased minimum water retaining agent mode increased the largest overall water retaining agent > fertilization > replacer soil > mulch >water retaining agent + mulch > comparison. Different periods of optimal treated in a different way, the early stage of water retaining agent + mulch > water retaining agent > replacer soil > mulch > fertilization> comparison and the middle period of fertilization > replacer soil >water retaining agent> water retaining agent + mulch>mulch> comparison, the late session for replacer soil > fertilization >water retaining agent >water retaining agent + mulch > mulch> comparison. ②Diameter at breast height index: the biggest change,the most significant is water retaining agent, followed by fertilization and water retaining agent + mulch, the comparison of the most stable growth of the most slow. The early stage effect is best of water retaining agent + mulch, followed by coverage, decreased gradually with the elapse of time effect;the middle period with water retaining agent, fertilization, soil are the best, late obviously decreased; late effect is soil, and tree height growth similar.③Crown index: different ways of artificial intervention has a significant role in promoting, mainly in the early stage, increasing with time and gradually slowed down, overall effect on: replacer soil > water retaining agent + mulch> fertilization > water retaining agent > mulch> comparison.(2)Vegetation type, forest age is an important factor to affect the growth of trees and to changes in the environment,With the change of environment adaptability and drought tolerance for primary fores >secondary forest; big arbor > shrub > small trees. The primary forest is better than that of secondary forest. Primary forest(Coriaria sinica) has been adapted to karst area of low temperature and drought environment itself has strong anti freezing anti drought growth habit, compared to foreign immigration shrub(Flos Lonicerae, Pistacia weinmannifolia) on human intervention model adaptability better. Tall trees, shrubs, small trees better than bush. Tall perennial arbor plants, root diameter, secular growth changes have been to the harsh environment of karst area has strong adaptability. Because of the low requirement of the environment, the shrub is not high, so it has good adaptability to the environment. 2 ~ 3 years old trees were shorter in time and higher in environmental requirement, and the effect of frost resistance and drought tolerance was the lowest when compared with that of large trees.(3)Different species have different response mechanisms in different modes. In each treatment mode, it follows the seasonal variation of the natural environment, but the numerical changes of different species in different seasons are different. Little effect on plant chlorophyll planting mode, evergreen species chlorophyll values have increased to some extent, slightly decreased average value of deciduous species; the effect of moisture on deciduous trees more than evergreen, evergreen tree of the time change is small and the maximum value appeared in the spring, but smaller SPAD deciduous species in each period varies greatly and the maximum the value in summer and autumn in spring, but for the low value area; effects of nutrient on vegetation chlorophyll obviously in the early stage of processing of evergreen trees and shrub species SPAD value increased more significantly, deciduous trees at this time chlorophyll value is low, the nutrient is not the key factors that influence the effect of mulching is minimal; processing technology, various species of chlorophyll the value of the whole spring and summer autumn season is larger, smaller; aquasorb and under the cover of each species in four seasons partial small value.(4)Some species responses to environmental changes, "premature" characteristics. The phenomenon is attributed to just move the plant species difficult to fit the harsh environment of the area, the main stem will dry dead, after a certain period of time after the plant to sprout growth to adapt to a changing environment, the density and contrast of Cinnamomum camphora, Broussonetia papyrifera performance more obvious, the seedlings of the two species is not conducive to growth in karst rocky desertification area.(5)There had the difference of Vegetation input and output effects.The Production costs include labor costs and raw material costs, through the analyzing of economic under the different ways, and the calculating the ecological effects of production cost and biomass increment,and we got the production costs, which was water retaining agent + mulch>replacer soil > mulch > water retaining agent> fertilization, and biomass optimization model water retaining agent + mulch > water retaining agent > replacer soil> fertilization > mulch>fertilization.Through the contrasting of these, water retaining agent and fertilization should become the artificial way in scientific, reasonable and effective optimal model. |
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