胶茶人工群落在改善山地土壤生态环境上的作用

Effect of Man-made Rubber-Tea Community Improving Ecological Condition of Soil

经过多年的实践和研究结果表明,橡胶(Hevea brasiliensis)-茶树(Camellia sinensis)两层人工群落结构,比单一橡胶种植模式有着明显的改善山地土壤生态环境的特点。胶-茶人工群落对减少水土流失,改善土壤微生物状况,增强土壤地表呼吸强度,促进团聚体形成和提高土壤肥力以及增加单产等方面,均有显著的效果。因此,胶-茶人工群落为合理利用我国西部热带山地资源,开辟了一条新的经营种植模式。

The man-made rubber-tea community has not only brought forth high economic efficacy and social benefits but also improved the ecological environment of soil. This paper mainly discusses the function that man-made rubber-tea community performs in the improvement of edaphic ecosystem. The experimental position was located east of the tropical botanic garden at longitude of 101°15'E, latitude of 21°41'N, and an elevation of 580m above sea level. The experimental plots chosen for comparisons were essentially consistent in direction and altitude of the slope, topography, edaphic condition and the level of fertilizer application. 1. The runoff and erosion in case of artificial rubber-tea community were decreased by 29.63 % and 24.37% , respectively, in comparison with the case of pure rubber plantation. 2. Actinomycetes 0 ~ 80 cm beneath the ground in artificial rubber-tea community are slightly less than those in pure rubber plantation, whereas bacteria, fungi and azotobacters in artificial rubber-tea community are 3.3, 1.5 and 1.7 times those in pure rubber plantation respectively. The 0 ~ 5 cm soil layer in artificial rubber-tea community contains 3,633,300 microorganisms/g dry soil, which is 2.2 times the number in pure rubber plantation (1,648,400). 3. When artificial rubber-tea community is compared with pure rubber plantation in the foggy, dry and wet season, CO2 released on the artificial rubber-tea community ground surface (under the rubber trees) was increased by 58.3% , 66.7% and 51.0% respectively, and when artificial rubber-tea community (under the tea bushes) is compared with pure tea plantation (under the tea bushes), with even greater differences, the amount of CO2 of the former are respectively (referring to the different seasons) 7.3, 2.5 and 2.2 times those of the latter. 4. The 0~20 cm soil layer under rubber trees in artificial rubber-tea community contains 62.05% of water-stable granules, and pure rubber plantation 57.49% , with an increase of 4.56% . The increase was also found under tea trees in artificial rubber-tea community as compared with pure tea plantation. 5. The 0~60 cm soil layer in artificial rubber-tea community contains 18.2g/kg organic matter and 0.93g/ kg total nitrogen; increasing by 18.95% and 4.49% respectively in comparison with soil in pure rubber plantation; increasing by 26.39% and 16.25% respectively, in comparison with soil in pure tea plantation. 6. Both mean yield of dry rubber and total value of output per hactare are higher in artificial rubber-tea community than in pure rubber plantation , with dry rubber yield increasing by 10.42 % , and total output value increasing by 72.20 % .