中文摘要：

为了探讨保护性耕作对旱作农田土壤呼吸的影响，采用L16400XT便携式光合作用测量系统n带的土壤呼吸室（6400—09）在重庆北碚西南大学试验农场对传统耕作（T，traditionalfarming）、垄作（R，ridgeplanting）、传统耕作＋秸秆覆盖（TS，traditionalfarming＋strawmulching）、垄作＋秸秆覆盖（RS，ridgeplanting＋strawmulching）、传统耕作＋秸秆覆盖＋秸秆速腐剂（TSD，traditionalfarming＋strawmulching＋decomposingagent）、偿作＋秸秆覆盖＋秸秆速腐剂（RSD，ridgeplanting＋strawmulching＋decomposingagent）6种处理下的西南紫色土丘陵区小麦／玉米／大豆套作体系巾作物生长季节的土壤呼吸及其水热闪子进行了测定和分析。结果表明，6种处理中土壤呼吸速率的季节变化明屁，各处理日均土壤呼吸速率差异显著。其中在小麦一大豆条带，小麦土壤呼吸速率均值为1．53μmnlm-2，大豆土壤呼吸速率日均值为4．10μmol-2.s-1，各处理日甲均土壤呼吸速率大小排序为T〈R〈TS〈TSD〈RS〈RSD。存空地一上米一窀地条带，玉米土壤呼吸日均值为2．56μmol-1s-1，介于小麦和人豆土壤呼吸速率之间，各处理日平均土壤呼吸大小排序为R〈T〈RS〈TS〈RSD〈FSD。整个套作体系土壤呼吸总量C为1543～2134gm-2，表现为T〈R〈RS〈TS〈TSD〈RSD．研究结果还显示土壤温度和土壤水分是影响旱地农田土壤呼吸的主要闪素，二者分别解释了土壤呼吸季节变化的28．9％～53．7％和13．7％～42．0％。水热洲子与土壤呼吸速率的回归分析表明，指数方程较好地模拟了土壤呼吸与10cm土温的关系，土壤呼吸的温度敏感性指标Q．。值在2．25～2．69之间；而土壤呼吸与5cm土壤水分的关系以抛物线型函数模拟最优。土壤呼吸对土壤水分的响应阈值为14．94％。该研究为明确农田生念系统土壤呼吸变化规律及影响因素的控制机理提高参考

英文摘要：

To investigate effects of tillage pattern on soil respiration in dry cropping farmlands in purple soil hilly re- gion in Southwest China,an LI6400-XT portable photosynthesis measurement system equipped with a soil respiratory cham- ber （6400-09） was used in an experiment conducted in the experimental field of the Southwest University in Beibei, Chongqing. Respiration and hydrothermal factors of the soils under the same wheat/corn/soybean triple intercropping sys- tem, but different tillage patterns were measured and analyzed during the crop growing period. The tillage patterns or treat- ments were coded as T （traditional tillage）, R （ridge tillage） ,TS （traditional tillage ＋ straw mulching）, RS （ridge till- age ＋ straw mulching） ,TSD （traditional tillage ＋ straw mulching ＋ decomposing inoculants） , and RSD （ridge tillage ＋ straw mulching ＋ decomposing inoculants） and each had 3 replicates. Results show that soil respiration rate varied signifi- cantly with the season and from treatment to treatment as well. The daily mean soil respiration rate under wheat and soy- bean in the wheat-soybean row was 1.53 μmol m-2 s J and 4. 10 μmol m 2 s-1 ,respectively and varied between treat- ments, displaying an order of T 〈 R 〈 TS 〈 TSD 〈 RS 〈 RSD. In the blank-corn-black row, the daily mean soil respiration rate of the soil under corn reached 2.56 ~mol m 2 s-＇ ,ranging between those under wheat and soybean,and varied be- tween treatments, displaying an order of R 〈 T 〈 RS 〈 TS 〈 RSD 〈 TSD. The total soil respiration rate of the field under the intercropping system was 1.54 ~ 2.13 g m-2 and varied between treatments, displaying an order of T 〈 R 〈 RS 〈 TS 〈 TSD 〈 RSD. The experiment also shows that soil temperature and soil moisture content were the two major factors affecting soil respiration,explaining 28.9 %-53.7 % and 13.7 %-42 % of its seasonal variation. Regression analysis of the relation- ship between soil respiration and soil hydrothermal factor