稻草与生石灰对设施土壤微量元素含量和番茄产量的影响

为了探究设施内添加稻草与生石灰对土壤微量元素含量和番茄产量的影响,以长期施肥定位试验为依托,比较了施用鸡粪(M)的基础上,添加稻草(MR)、生石灰(MCa)、稻草与生石灰同时添加(MRCa)各处理全土及各粒级团聚体中有效态Fe、Mn、Cu、Zn含量和番茄产量的变化。结果表明:(1)添加稻草可增加土壤中有效态Fe、Mn、Zn含量,MR处理较M处理分别增加3.2%,80.9%,15.1%,对有效态Cu含量无显著影响;添加生石灰也可增加土壤中微量元素含量,其中Mn含量增加显著。土壤中有效态Fe、Mn、Cn、Zn含量与pH呈极显著负相关(P<0.01),与有机质含量呈极显著正相关(P<0.01)。(2)随着土壤团聚体粒级的减小,有效态微量元素含量呈下降趋势。添加稻草和生石灰可增加1~0.25mm粒级中有效态Mn含量,MRCa处理较其他处理增加6.6%~46.6%;添加稻草可增加<0.25mm粒级中有效态Zn含量。土壤中有效态Fe含量与<1mm粒级中含量呈显著正相关(P<0.01);土壤中有效态Mn、Zn含量分别与各粒级中含量呈显著正相关(P<0.01);土壤中有效态Cu含量与1~0.25mm粒级中含量呈显著正相关(P<0.01)。(3)施入稻草或生石灰可增加番茄产量,且稻草和生石灰同时施入产量最高,MRCa处理较MCa、MR处理分别增加12.6%,33.8%。土壤有效态Fe、Cu含量与产量正相关,其中有效态Fe含量对产量具有直接作用,决策系数最高,土壤有效态Cu含量对产量具有间接作用。因此,可以通过长期添加稻草和适量生石灰缓解设施土壤微量元素短缺的现状,且可获得最高作物产量,为设施内土壤可持续利用和设施农业可持续发展提供保障。

Effects of Straw and Lime Additions on the DTPA-extractable Micronutrients Contents and Tomato Yield in Greenhouse Soil

To evaluate the effects of straw and lime application on soil micronutrients and tomato yield, soils from plots amended with no fertilizer (CK), chicken manure (M), chicken manure + straw (MR), chicken manure + lime (MCa), chicken manure + straw + lime (MRCa) were collected. The results showed that:(1) Straw increased the contents of DTPA-extractable Fe, Mn and Zn in soil, MR caused 3.2%, 80.9% and 15.1% increase compared with M, respectively. Lime increased the contents of DTPA-extractable Fe, Mn, Cu, Zn in soil. The DTPA-extractable Fe, Mn, Cu and Zn contents in soil were significantly correlated with soil pH values and organic matter contents (P<0.01). (2) The micronutrients decreased as the aggregate sizes decreased. Adding straw and lime increased the DTPA-extractable Mn content in soil aggregate of 1~0.25 mm, MRCa caused 6.6%~46.6% increase compared with other treatments. Straw increased the DTPA-extractable Zn content in the aggregate<0.25 mm. The DTPA-extractable Fe content in soil was positively correlated with that in aggregate of <1 mm (P<0.01), the DTPA-extractable Mn and Zn contents were positively correlated with those in all aggregates sizes (P<0.01), and the DTPA-extractable Cu content in soil was positively correlated with that in aggregate of 1~0.25 mm (P<0.01). (3) Straw or lime increased tomato yield, the MRCa treatment had the highest yield, which was 12.6%~151.1% higher than other treatments. The DTPA-extractable Fe and Cu contents in soil were positively correlated with yield. The DTPA-extractable Fe had a direct effect and it sdecision coefficient was the highest. The DTPA-extractable Cu had an indirect effect. Therefore, straw and lime could alleviate the shortage of micronutrients in greenhouse soil, and the maximum crop yield could be obtained, which guaranted the sustainable utilization of soil in greenhouse and the sustainable development of greenhouse agriculture.