塑料大棚番茄渗灌多孔管埋深的研究

渗灌管的埋深是渗灌的重要技术参数之一。本试验以6kPa和40kPa分别作为保护地渗灌的灌水上限和灌水下限，以土壤水分张力计读数控制灌水起始点，研究了不同的多孔管埋深(分别为20、30、40cm)对保护地土壤水分状况和温度状况等土壤环境条件以及番茄生长发育状况、产量、外观品质和水分利用率的影响。研究结果表明，与埋深20cm和40cm相比，渗灌多孔管埋深为30cm时，番茄生长的根区土壤水分含量适中，土壤温度在白天上升较快，土壤肥力状况较好，番茄干物质积累较多，生长发育较好，有利于提高番茄产量、外观品质和分利用率，有利于田间耕作管理。这一技术参数最适宜于塑料大棚番茄栽培应用，相应的灌水周期为8d左右，每次灌水量为225m^3／hm^2。

BURIED DEPTH OF POROUS PIPE FOR SUBSURFACE DRIP IRRIGATION IN TOMATO CULTIVATION IN SUNLIGHT GREENHOUSE

The buried depth of porous pipe is one of the important technological parameter for subsurface drip irrigation(SDI).In this paper, a sunlight greenhouse experiment was conducted to investigate the effects of different buried depths of porous pipe for SDI on soil water, temperature regime, water use efficiency,the growth, the yield, and the appearance of the tomato. In the experiment, three treatments were used: T20) the buried depth (BD) of SDI was 20 cm; T30), the BD was 30cm;and T40) the BD was 40 cm, and the upper and lower irrigation limits for SDI were designated as 6 kPa and 40 kPa,respectively. The readings of tensiometers which ceramic heads buried in 30 cm depth under soil surface were applied to indicating irrigation application. The results suggested that in the treatment T30, the soil water regime of tomato root zone was moderate for tomato growth, the soil temperature increased fast in the daytime and the soil fertility was higher compared with treatment T20 and T40. The tomato plants in treatment T30 grew well, and the biomass of the tomato was higher than that in other treatments. Treatment T30 was in favor of increasing the yield, improving the appearance of the tomato, and enhancing the water use efficiency, and reducing labor costs. Therefore, the parameter of 30 cm of buried depth was optimist for SDI in tomato cultivation in the sunlight greenhouse.The corresponding irrigation interval could be about 8 days, and the irrigation rate 225 m 3.hm -2 per event.