| This paper aimed at exploring the indicating effect of large soil fauna to ecological resume benefit in arid and semiarid regions of Loess Plateau.16 field plots of different vegetations types and terrain characteristics were set in Longtan watershed, Anding district, Gansu province. Numerous field sampling and laboratory experiments works have been preformed during 2009 and 2010. In all,340 samples of soil, soil fauna and vegetation were collected as the base of original data. The mathematical and statistical methods were used to explore the relationship between soil fauna communities and environmental factors such as soil moisture and soil nutrition content. Furthermore, method system that can be adopted to assess drought environment resume was built and drought tolerant plants were also chosen accordingly. Finally, the best drought reparation pattern had been chosen based on the environmental indicating effect of soil fauna. Several results can be concluded as fowling:(1) Only few soil fauna types were found in the small communities because of the drought environment, which would lead to the rare vegetation and in turn reduced the food supplements for soil faunas. Sampled soil faunas could be classified as 1 phyla,2 classes,8 orders and 23 familys. Among them, the advatage group are Formicidae,Staphylinidae,Anthocoridae, familiar groups are Cicadellidae,Cantharidae,Carabidae and so on. There are significant differences between the environment suiting capabilities of different soil faunas. On the other hand, there are also difference exist between soil faunas communities and individual number under different plants. Both the two factors can be ordered as Korshinsk Peashrub>Siberian Apricot>Chinese pine>arborvitae>Amygdalus tangutica according to plant types. Soil faunas were found accumulated in the surface layer of soils. Both thegroupsand individual number can be ordered as (0-5cm)> (5-10cm)> (10-15cm) according to the depth of soil profile.(2) Comparison of different physiological factors among 5 plants showed significant difference exist between each plant species. The drought torrent ability of 5 plants were ordered as Korshinsk Peashrub> arborvitae> Chinese pine> Siberian Apricot> Amygdalus tangutica based on the assessment of the method of subordinate function value. On the other hand, the corrolation degree of physiological factors to drought grade were ordered as free proline content> Chlorophyll content> the ratio between bound water and free water>the glutathione content> mda> the soluble suger content and the glutathione content throught the the grey correlative analysis.(3) The ecological effect of different plant recover modes were assessed based on the indicating effect of soil fauna. The order could be made accordingly as Korshinsk Peashrub> Siberian Apricot> Chinese pine>arborvitae>Amygdalus tangutica. It can be concluded that Korshinsk Peashrub mode can adapt the drought situation well and can generate a high ecological effect. Hence the Korshinsk Peashrub mode can be chosen as the optimal recover mode to be used in semi-drought regions of the Loess Plateau. On the other hand, the Amygdalus tangutica can not adapt the drought situation well and has a poor ecological effect compared with other plants. Thearborvitae, Chinese pine and Siberian Apricot modes can be adopt as considering the practical situation.
|
PDF Full Text Request