| Various construction projects could produce lots of waste soil and residue during the construction, the soil of spoil ground lacked of nutrients and be poor of soil structure, plants were difficult to grow. In order to provide a technical basis for soil improvement and fertilizing in the gully region of The Loess Plateau, the simulation of spoil ground was constructed in Chang Wu, Shannxi Province, Loess Plateau. Trrifolium repens L., Melilotus suaveolens Ledeb., Coronilla varia L., Caragana Korshinskii Kom.and Lolium perenne L. were taken as research object, the soil nutrient in 0-10 cm,10-20 cm of the spoil ground of these plants under organic fertilizerã€straw and no fertilizer have been researched. Meanwhile, measuring the soil moisture content from 0 to 100 cm and available nutrients content(inclue N, P, K) from 0 to 20 cm in the lab, and there were three conditions AO(Organic fertilizer, no plants), BO(straw, no plants) and CK(without fertilization, no plants)to study the soil fertility of spoil ground by different fertilizing plants under single-sowing and mixed.The main conclusions were as follows:(1)Compared with the control(AO), soil moisture increased of 56.06% on average under organic fertilizer, and compared with the control(BO) increase of 34.75% under straw. The increase was higher 82.35% than the control(CK) without fertilizer. The content of water were higher than control in three different fertilization treatments. However, its amplification of fertilization was higher than without fertilization. And same influence existed between organic fertilizer and straw returned;(2)The subordinate function values have been taken to analysis the soil fertility of five species, the comprehensive evaluation results showed: under organic fertilizer: Lolium perenne L.+Trrifolium repens L > Caragana Korshinskii Kom.> Coronilla varia L.+Melilotus suaveolens Ledeb.> Melilotus suaveolens Ledeb.> Melilotus suaveolens Ledeb.; under straw: Melilotus suaveolens Ledeb.> Caragana Korshinskii Kom.> Lolium perenne L.+Trrifolium repens L. > Lolium perenne L.> Coronilla varia L.+Melilotus suaveolens Ledeb.; Without fertilizer: Melilotus suaveolens Ledeb.> Lolium perenne L.+Trrifolium repens L. > Caragana Korshinskii Kom.> Coronilla varia L.+Melilotus suaveolens Ledeb. > Lolium perenne L.;(3)Effect of improving soil in mixed-sowing was better than single-sowing in organic fertilizer. Plant single-sowing was better than mixed-sowing under straw treatment. However, mixed-sowing was better than single-sowing without fertilizer. Under plant single-sowing, the order of functional value evaluation was Melilotus suaveolens Ledeb.(0.54), Caragana Korshinskii Kom.(0.53), Lolium perenne L.(0.21), Lolium perenne L.+ Trrifolium repens L. was higher than > Coronilla varia L.+ Melilotus suaveolens Ledeb.(0.37);(4)The increased of soil nutrient in fertilizer was less than straw. Compared with AO, soil nutrients increased 3.61% in organic. Soil nutrient content was higher than BO in straw condition. Compared with CK, soil nutrient content was less 10.45% without fertilizer. Therefore, suitable fertilization was good way to boost process of soil cultivation as improving soil nutrient of spoil ground;(5)Compared with CK of different plant plot, soil nutrient decreased in three various fertilization conditions. It would take some time for the organic and straw to exchange into nutrients that could be absorbed by plants. The content of soil nutrient showed a downward trend in early stage as soil nutrient was consumed by the decomposition of straw and organic fertilizer and plant growth. Therefore, fertilizer, water, sunshine were required by soil in the early of soil cultivation;(6)In soil nutrient content, there was no obvious difference in first investigation. However, big difference among every site after four months result from different nutrient required by plant growth. So, average soil nutrient content of second time less than first time generally as nutrient consumption by organic fertilizer, straw decomposition and plant growth. |
