北方高寒区不同覆盖条件下土壤温度差异性分析

Variability of Soil Temperature under Different Coverage Conditions in Alpine Region of China

以北方寒区典型城市哈尔滨市的大田为研究区域,通过冬季大田试验(试验周期2013-11-01—2014-04-30),设置裸地、5、10和15 cm厚度秸秆覆盖4个处理,分别测定不同处理条件下3、5、8、10、15、20、40、60、100、140 cm等深度土壤温度以及气温和太阳总辐射,采用统计学理论对其进行对比分析。研究结果表明:秸秆覆盖对于热量具有双向阻碍作用,只是在不同的外界条件下双向阻碍作用的主导地位在不断调整;某深度下土壤温度变化是秸秆覆盖与土壤导热性相互作用的结果;裸地温度差异性最大,其次为5 cm秸秆覆盖和15 cm秸秆覆盖,最后为10 cm秸秆覆盖,秸秆覆盖对于土壤温度差异系数的影响并非随着秸秆厚度的增加单调增加。

Choosing Harbin as the study area,a city of typical cold climate,through the field experiment in winter（ from 2013-11-01 to 2014-04-30）,we measured soil temperature in the depth of 3 cm,5 cm,8 cm,10 cm,15 cm,20 cm,40 cm,60 cm,100 cm,and 140 cm with four control groups（ bare land,5 cm thickness of straw mulch,10 cm thickness of straw mulch,15 cm thickness of straw mulch）,and air temperature and solar total radiation under different control group. The statistical analysis results show that the straw mulch can prevent heat transfer in two directions,and its dominance varies with the outer environment. Under a certain depth the soil temperature is determined by the interaction between soil thermal conductivity and straw mulching conditions. The temperature of bare land has the biggest change rate,followed by the 5 cm thickness of straw mulch and the 15 cm thickness of straw mulch,and the last is the 10 cm thickness of straw mulch,which means that the influence of straw mulching on soil temperature does not increase monotonously with the increase of the thickness of the straw.