胡椒园间作槟榔体系小气候对胡椒产量的影响

Effects of Microclimate Factors on Black Pepper Yield in the Black Pepper/Arecanut Intercropping System

为确定胡椒园间作槟榔体系影响胡椒产量的关键小气候因子,在海南胡椒园间作槟榔优势区开展4种间作模式与单作胡椒园小气候因子对产量影响的为期4 a的试验,研究不同间作密度下,对胡椒产量有主要贡献的灌浆期的叶片光合作用参数、每日最高和最低气温、不同深度土层土壤温度和含水量,分析胡椒园间作槟榔体系小气候因子对胡椒产量的影响。结果表明:合理间作可以提高胡椒产量,其中间作槟榔株数为765株/hm2的T2处理可以显著提高胡椒产量38.71%,为增产效应最大的处理。分析T2处理增产的原因,发现光强影响的关键光合参数气孔导度对产量有极显著正效应,光合有效辐射、光合速率对产量有显著正效应,T2处理显著提高了这三个光合参数;高温干旱的灌浆期胡椒园日最高温和升温幅度与产量负相关,T2处理显著降低了这两个参数,使胡椒产量增加;表层土壤温度与产量呈负相关关系,T2处理显著降低了表层土壤温度,对胡椒根系有保护作用。综合分析,发现光合有效辐射、日最高温、升温幅度和表层土壤温度是影响胡椒产量的关键小气候因子,所以,这几种小气候因子是用来确定间作模式是否合理的关键参数。

In order to determine the key microclimate factors which influence the production of pepper in intercropping system, experiments which had 4 intercropping models and monoculture as the control in pepper/arecanut intercropping advantage region of Hainan from 2009 to 2012 were conducted. Photosynthesis parameters of fully expanded leaves, maximum and minimum air temperature, soil temperature and moisture content in different depth at the filling stage were determined. The effects of microclimate factors on black pepper yield in intercropping system were analyzed. The results showed that the yield of black pepper increased in appropriate black pepper/arecanut intercropping systems. The T2 treatment that intercropping arecanut 765 plant/ha was the optimum intercropping model which could increase pepper yield 38.71% compared to momoculture. Analyzing the reason of T2 yield increase found that the key photosynthetic parameter of stomatal conductance which was affected by light intensity had a very significant positive effect on the yield. The photosynthetic active radiation and net photosynthetic rate had a significant positive effect on the yield. T2 could improve the three photosynthetic parameters. The maximum air temperature and air temperature rise had a negative correlation with yield. The two parameters decreased in filling stage and increased pepper yield in the T2 treatment. There was a negative correlationship between topsoil temperature and yield. T2 also reduced the soil temperature to defend pepper root from injury. Photosynthetic active radiation, the maximum air temperature, air temperature rise and topsoil temperature were the key microclimate factors impact on the pepper production of composite analysis. Therefore, the key microclimate factors used to judge an intercropping mode is reasonable.