有机无机复合保水材料对玉米苗期土壤水分及幼苗生长的影响

Effects of Organic-Inorganic Superabsorbent Polymer Composites on Soil Moisture and Growth of Maize at Seedling Stage

将聚丙烯酰胺(PAM)、凹凸棒土(NA)、腐植酸(FA)和秸秆炭(CB)按不同比例混合组成T1(PAM:NA:FA:CB=4:3:2:1)、T2(PAM:NA:FA:CB=4:3:1:2)、T3(PAM:NA:FA:CB=5:2:2:1)、T4(PAM:NA:FA:CB=5:2:1:2)共4种处理,同时以不施保水材料处理为对照(CK),研究有机无机复合保水材料对玉米苗期土壤水分及幼苗生长的影响,以期为北方干旱、半干旱区玉米生产中保水剂的合理施用提供科学依据。结果表明,不同保水材料处理的土壤水分累积蒸发率总体上均显著低于CK,具体表现为T4<T3<T2<T1<CK,且各有机无机复合保水材料处理土壤水分累积蒸发率总体上均随着有机无机复合保水材料施用量的增加而降低;土壤含水率及玉米幼苗株高、叶面积、茎粗、干物质积累量均显著高于CK,均表现为T4>T3>T1>T2>CK。当有机无机复合保水材料施用量为0.013~0.053 g/kg时,施用量越高,土壤水分累积蒸发率越低,土壤含水率越高;施用量为0.053 g/kg时,对玉米幼苗长势具有明显的促进作用,此时,玉米幼苗株高、叶面积、茎粗以及干物质积累量均为最佳。总体上,当有机无机复合保水材料施用量为0.053 g/kg时,T4处理可以有效降低土壤水分累积蒸发率,提高玉米苗期的土壤含水率,促进玉米幼苗生长。

To provide some scientific basis for the reasonable application of organic-inorganic superabsorbent polymer composites in corn production in the semi-arid,arid areas of northern China,the effects of organic-inorganic superabsorbent polymer composites[polyacrylamide(PAM),attapulgite(NA),humic acid(FA),straw biochar(CB)]on soil moisture and growth of maize seedling were studied with five treatments including T1(PAM:NA:FA:CB=4:3:2:1),T2(PAM:NA:FA:CB=4:3:1:2),T3(PAM:NA:FA:CB=5:2:2:1),T4(PAM:NA:FA:CB=5:2:1:2)and the control(CK)without organic-inorganic superabsorbent polymer composites.The results showed that all the composite treatments significantly decreased the cumulative evaporation rate of soil water compared with CK,the order was T4<T3<T2<T1<CK,and the cumulative evaporation rate of soil water decreased with the increase of application rate of organic-inorganic superabsorbent polymer composites.Soil moisture content,plant height,leaf area,stem diameter and dry matter accumulation of maize seedling were significantly higher than CK,and the order was T4>T3>T1>T2>CK.When the application rate of organic-inorganic superabsorbent polymer composites was 0.013—0.053 g/kg,the cumulative evaporation rate of soil water decreased,the soil moisture content increased with the increase of application rate of organic-inorganic superabsorbent polymer composites.When the application rate of organic-inorganic superabsorbent polymer composites was 0.053 g/kg,the growth of maize seedling was obviously promoted,and the plant height,leaf area,stem diameter and dry matter accumulation of maize seedling were the highest.These results suggested that the T4 treatment was a best way to reduce the cumulative evaporation of soil water,increase the soil moisture content,and promote the growth of corn seedling with the superabsorbert polymer composites of 0.053 g/kg.