污泥堆肥施用对土壤单位有机碳矿化及温度敏感性的影响  

Effects of Composted Sludge Addition on Soil Unit Organic Carbon Mineralization and Its Temperature Sensitivity

作　　者：闵旭旭 肖列[1] 李鹏[1] 刘然 赵萌[1] 刘方园 MIN Xuxu;XIAO Lie;LI Peng;LIU Ran;ZHAO Meng;LIU Fangyuan(State Key Laboratory of Eco-hydraulics in Northwest Arid Region,Xi′an University of Technology,Xi′an 710048,China)

机构地区：[1]西安理工大学省部共建西北旱区生态水利国家重点实验室,西安710048

出　　处：《水土保持研究》2023年第4期130-136,共7页Research of Soil and Water Conservation

基　　金：国家自然科学基金(41701603);黄土高原土壤侵蚀与旱地农业国家重点实验室基金课题(A314021402-202107);陕西省教育厅协同创新中心项目(22JY043)。

摘　　要：[目的]揭示污泥堆肥施用后土壤单位有机碳矿化及温度敏感性(Q_(10))对于市政污泥资源化利用和土壤碳库稳定性的主控因素,并进而为市政污泥处理及土壤有机碳固持提供理论支撑。[方法]以黄土丘陵区退化草地土壤为研究对象,测定了不同污泥堆肥添加比例(0,2.0%,5.0%,10.0%,15.0%,20.0%)和培养温度(15℃,25℃和35℃)下土壤有机碳矿化速率,探讨了污泥堆肥添加对土壤有机碳矿化特征和Q_(10)的影响。[结果](1)与CK相比,不同污泥堆肥添加在培养初期土壤单位有机碳矿化速率显著增加(p<0.01),之后迅速下降直至趋于稳定;而施用污泥处理组的土壤单位累积矿化量是CK的1.6~4.2倍,在施用比例达到10.0%~20.0%时其有机碳矿化速率与累积矿化量均差异不显著。(2)运用一级动力学方程,拟合不同温度不同污泥添加土壤单位有机碳矿化动态均达到较好效果(R 2>0.95),潜在矿化势(C_(0))值在6.92~39.60 mg C/g差异显著(p<0.05),土壤有机碳矿化速率常数(k)范围为0.03~0.12 d,与温度显著相关(p<0.01)。(3)Q_(10)随污泥堆肥施用量的增加其范围为1.18~2.58,在施用量达到10.0%时Q_(10)最大,之后随着施用比例的进一步增加Q_(10)反而降低。[结论]在污泥堆肥施入量控制在10.0%~20.0%时能够显著增加土壤有机碳含量,并抑制土壤有机碳的再度矿化有效调整土壤Q_(10),确保土壤碳库的相对稳定,并且有利于土壤单位有机碳的固持。[Objective]The main controlling factors of soil organic carbon mineralization and its temperature sensitivity(Q_(10))for municipal sludge resource utilization and soil carbon pool stability after sludge compost application were revealed,which provided theoretical support for municipal sludge treatment and soil organic carbon sequestration.[Methods]In the present study,different doses of composted sludge(0,2.0%,5.0%,10.0%,15.0%,and 20.0%)were added to the degraded grassland soil collected from the loess hilly area,and the soil organic carbon mineralization rates under different incubation temperatures(15℃,25℃and 35℃)were measured.The effects of composted sludge addition on soil organic carbon mineralization characteristics and Q_(10)values were discussed.[Results](1)Compared with CK,the soil organic carbon mineralization rate significantly(p<0.01)increased with composted sludge addition doses at the initial stage of cultivation,and then it rapidly decreased until it reached to a stable value.The cumulative soil organic carbon mineralization under the composed sludge addition treatments were 1.6~4.2 times greater than that of CK.When the composed sludge application doses were between 10.0%and 20.0%,the organic carbon mineralization rate and cumulative mineralization amount had no significant difference.(2)The first-order kinetic equation was used to fit the dynamics of soil organic carbon mineralization with composted sludge addition treatments at different incubation temperatures and achieved good results(R 2>0.95).Soil organic carbon mineralization potential(C_(0))values ranged from 6.92 to 39.60 mg C/g and the differences were significant(p<0.05)among different treatments.The soil organic carbon mineralization kinetic constant(k)ranged from 0.03/d to 0.12/d,and it was significantly correlated with incubation temperatures(p<0.01).(3)The Q_(10)values ranged from 1.18 to 2.58 with the composted sludge application doses,and the Q_(10)reached the maximum value when the application doses reached 10.0%,and then t

关 键 词：污泥堆肥 单位有机碳矿化 潜在矿化势 温度敏感性 

分 类 号：S157.41[农业科学—土壤学]