秸秆还田下改良剂对水稻生长和Cd吸收积累的影响

Effect of Amendments on Rice Growth and Cd Uptake Based on Straw Returning

土壤中的镉（Cd）易在水稻中积累而威胁人体健康,秸秆还田下不同化学改良剂对水稻Cd 吸收累积特性的影响效应值得关注.选取成都平原德阳市旌阳区Cd 污染稻田为研究对象,开展小区试验,研究秸秆（油菜、小麦）直接还田下添加石灰、钙镁磷肥、海泡石3 种改良剂对水稻生长和Cd 吸收累积的影响.结果表明：与对照相比,油菜秸秆＋钙镁磷肥和小麦秸秆＋海泡石处理均能增加水稻株高、分蘖数和产量,其中产量提高了6.34%和12.64%,达显著水平（P〈0.05）.秸秆还田下,配施改良剂（石灰、钙镁磷肥、海泡石）均能显著降低（P〈0.05）水稻糙米Cd 含量,较对照降幅分别为21.65%-36.75%（油菜秸秆还田）和21.11%-33.87%（小麦秸秆还田）.油菜秸秆＋改良剂（石灰、钙镁磷肥、海泡石）促进了土壤Cd 向茎叶的累积,较对照增加1.31-2.41 倍,这对水稻秸秆（茎叶）还田利用有不利影响.小麦秸秆＋石灰或海泡石处理均显著降低了茎秆、谷壳Cd 积累,较对照降幅为6.28%-19.63%和70.16%-78.68%.综合水稻产量及其对土壤Cd 吸收累积效应,油菜秸秆配合改良剂（海泡石、石灰和钙镁磷肥）、小麦秸秆＋海泡石是较为理想的秸秆还田与改良剂配合处理技术.

Abstract：Soil cadmium （Cd） was easy to accumulate in rice and threat to human health. The effects of chemical amendments on Cdabsorption characteristic in rice under the rice straw returning was worthy of attention. The cadmium （Cd） contaminated paddy fieldwas selected as the experiment plots in Jingyang, Deyang city, Chengdu Plain. The effects of three chemical amendments （lime,calcium-magnesia phosphate fertilizer and sepiolite） on the rice growth, Cd uptake and accumulation in rice were studied underthe straw （rape and wheat） returning directly in the plot experiment. The results showed, compare with the conventional treatment,the calcium-magnesia phosphate fertilizer addition based on the rape straw returning and the sepiolite addition based on the wheatstraw returning, which could promote the rice height, tiller number and rice yield, increased the rice yield for 6.34% and 12.64%respectively, the promoting effects were significant （P〈0.05）. The chemical amendments （lime, calcium-magnesia phosphatefertilizer and sepiolite） addition based on the straw returning reduced the content of Cd in brown rice effectively, reduced the ratio of21.65%-36.75% （rape straw returned）, and 21.11%-33.87% （wheat straw returned） respectively （P〈0.05）. All the amendments （lime,calcium-magnesia phosphate fertilizer and sepiolite） treatments based on the rape straw returning, which promoted the Cdaccumulation in rice stem and leaf, increased for 1.31-2.41 times compared to the conventional treatment （P〈0.05）. This may behave an adverse impact on the rice aboveground （stem and leaf） recycling in paddy field directly. The lime or sepiolite addition basedon the wheat straw returning reduced the accumulation of cadmium in the stalks, chaff, and brown rice significantly, which reducedthe ratio of 6.28%-19.63% and 70.16%-78.68% respectively compared with the conventional treatment（P〈0.05）. Comprehensivethe rice yield and Cd absorption in rice, the chemical amendments （lime, calcium-magnesia phosphate fertilizer and sepiolite）addition based on the rape straw returning and the sepiolite addition based on the wheat straw returning were the ideal cooperationtreatment of straw returning and chemical amendments.