Li X S, Han H F, Ning T Y, Lal R
College of Agronomy, State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, Shandong Agricultural University Tai'an 271018 Shandong P. R. China
Carbon Management and Sequestration Center, School of Environment and Natural Resources, The Ohio State University Columbus OH 43210 USA.
RSC Adv. 2018 Apr 3;8(23):12588-12596. doi: 10.1039/c8ra00708j.
A laboratory incubation experiment was conducted to assess the impact of straw input on CO-C emissions. After the winter wheat ( L.) growing season, soil samples were collected from the 0-20 cm soil layer. The experiment was conducted on a brown loam soil, classified as a Udoll according to the U. S. soil taxonomy. Treatment levels consisted of three tillage practices: sub-soiling (ST), no-till (NT) and the conventional tillage (CT), two straw management (with and without input of straw), three temperature (25, 30 and 35 °C), and three moisture regimes (55%, 65% and 75% of field moisture capacity or FMC). The results showed that the rate of straw decomposition was the highest in the soil under NT management. The relationship between rate of cumulative CO-C and straw decomposition was significant under NT ( = 0.52). The soil CO-C release under incubation was significantly higher with than without the input of straw ( = 0.95). Furthermore, soil respiration increased with increases in incubation temperature and FMC. At 75% FMC, the rate of CO-C release increased by 21.9 mg kg d at 30 °C and 32.0 mg kg d at 35 °C compared with that at 25 °C. At 35 °C, the rate of CO-C release increased by 43.6 mg kg d at 65% FMC and 51.2 mg kg d at 75% FMC incubation than that of at 55% FMC under ST. The degree of control on the CO-C evolution rate during the pre-incubation period and with higher incubation temperature and FMC was better for the soil from NT than that from CT and ST, and better yet for the soil from ST than that from CT.
进行了一项实验室培养实验，以评估秸秆投入对CO-C排放的影响。冬小麦生长季节结束后，从0-20厘米土层采集土壤样本。实验在一种棕色壤土上进行，根据美国土壤分类法，该土壤被归类为乌德土。处理水平包括三种耕作方式：深松（ST）、免耕（NT）和传统耕作（CT），两种秸秆管理方式（有秸秆投入和无秸秆投入），三种温度（25、30和35°C），以及三种水分状况（田间持水量的55%、65%和75%）。结果表明，免耕管理下土壤中秸秆分解速率最高。免耕条件下，累积CO-C速率与秸秆分解之间的关系显著（r = 0.52）。培养期间，有秸秆投入时土壤CO-C释放量显著高于无秸秆投入时（r = 0.95）。此外，土壤呼吸随着培养温度和田间持水量的增加而增加。在田间持水量为75%时，30°C下CO-C释放速率比25°C时增加了21.9毫克/千克·天，35°C时增加了32.0毫克/千克·天。在35°C下，深松条件下，田间持水量为65%时CO-C释放速率比田间持水量为55%时增加了43.6毫克/千克·天，田间持水量为75%时增加了51.2毫克/千克·天。免耕土壤在预培养期以及较高培养温度和田间持水量条件下对CO-C释放速率的控制程度优于传统耕作和深松土壤，深松土壤又优于传统耕作土壤。
