安徽稻油两熟制不同种植方式下气候资源配置和演变

Climate resource allocation and evolution of rice-oilseed rape double cropping system under different planting patterns in Anhui Province

安徽沿江地区稻-油复种模式下茬口衔接紧密、光温资源紧张,季节间气候资源配置备受关注。移栽和直播是补充和调配气候资源的有效种植方式,而稻油两熟制中不同种植方式下不同作物生长季气候资源配置、演变特征以及对未来气候变化的适应性尚不清晰。本研究以安徽沿江地区27个气象站1992—2022年的气温、日照时数、总辐射和降水等气象资料为基础,分析了不同种植方式下稻-油复种季节间气候资源配置与演变特征以及光温生产潜力。结果表明,近30年稻-油复种模式下季节间总辐射量、日照时数和光合生产潜力均呈下降趋势,气温、降水量和光温生产潜力呈上升趋势。水稻季移栽和直播方式下总辐射量倾向率分别为-27.9 MJ·m^(-2)·(10a)^(-1)和-28.8MJ·m^(-2)·(10a)^(-1),油菜季分别为-40.5 MJ·m^(-2)·(10a)^(-1)和-26.6 MJ·m^(-2)·(10a)^(-1)。水稻季移栽和直播方式下平均日最高气温倾向率分别为0.30℃·(10a)^(-1)(P<0.05)和0.24℃·(10a)^(-1),最高达32.70℃(2022年,青阳)。油菜季移栽和直播方式下平均气温倾向率分别为0.36℃·(10a)^(-1)(P<0.01)和0.39℃·(10a)^(-1)(P<0.01),移栽方式下平均气温较直播方式高0.96~1.43℃。稻油两熟制两季均面临光资源持续下降和气温不断上升等问题,采用移栽方式可通过延长作物生育期优化光、温资源配置,提高光温生产潜力。同时,适当推迟移栽期将有利于应对油菜苗期和水稻花期的高温。直播方式下宜采用高光效品种和构建光资源高效利用作物群体。

Because the rice-oilseed rape double cropping system along the Yangtze River in Anhui Province shows tight stubble convergence together with light and temperature resources,it has attracted a lot of attention with regard to inter-seasonal climate resource allocation.Although transplanting and direct seeding are effective planting strategies for supplementing and deploying climate resources,the climate resource allocation and evolutionary characteristics in each growing season of different crops in rice-oilseed rape double cropping systems under different planting patterns as well as their adaptation to future climate change remain unclear.In this study,the inter-seasonal climate resource allocation and evolution characteristics as well as radiation-temperature production po-tential of the rice-oilseed rape double cropping system under different planting patterns were analyzed on the basis of meteorological datasets,such as air temperature,sunshine hours,total radiation,and precipitation,recorded from 1992 to 2022 at 27 meteorological stations along the Yangtze River in Anhui Province.The results showed that in the last 30 years,the inter-seasonal total radiation,sunshine hours,and photosynthetic production potential had decreased while the air temperature,rainfall,and radiation-temperature production potential had increased under the rice-oilseed rape double cropping system.In the rice season,the total radiation tendency rates under the transplanting and direct seeding pattern were-27.9 MJ·m^(-2)·(10a)^(-1)and-28.8 MJ·m^(-2)·(10a)^(-1),respectively.In the oil-seed rape season,the total radiation tendency rates under the transplanting and direct seeding pattern were-40.5 MJ·m^(-2)·(10a)^(-1)and-26.6 MJ·m^(-2)·(10a)^(-1),respectively.During the rice season,the mean daily maximum temperature tendency rates under the transplant-ing and direct seeding pattern were 0.30℃·(10a)^(-1)(P<0.05)and 0.24℃·(10a)^(-1),respectively.The highest mean daily maximum tem-perature in the rice season reached 32.70℃in 2022(Qingyang County,Anhui Province,China).During the oilseed rape season,the mean temperature tendency rates were 0.36℃·(10a)^(-1)(P<0.01)and 0.39℃·(10a)^(-1)(P<0.01)under the transplanting and direct seed-ing patterns,respectively,with the mean temperature being higher under the transplanting pattern than under direct seeding.The tend-ancy rate of radiation-temperature production potential under direct seeding pattern was 170.2 kg·hm^(-2)·(10a)^(-1)in the oilseed rape sea-son,which was higher than that under transplanting pattern.Thus,it appears that the direct seeding pattern has more potential to be explored for increasing yields in the oilseed rape season in the future.Both crop seasons within this double cropping system have faced problems,such as a continuous decline in light resources and a constant rise in air temperature.Adopting the transplanting pat-tern could increase the allocation of light and temperature resources to improve the radiation-temperature production potential by ex-tending the crop reproductive period.Hence,the adoption of transplanting in both crop seasons would be an effective measure to cope with climate change and yield more production potential along the Yangtze River in Anhui Province.Meanwhile,delaying the trans-planting date would be helpful to cope with warming at the oilseed rape seedling and rice flowering stages.Direct seeding resulted in less allocation of climatic resources than transplanting,and using high light-efficient varieties and building crop populations with effi-cient use of light resources are desirable.