Based on simulation results from the 16 CMIP5 model runs under three Representative Concentration Pathways(RCP2.6, RCP4.5, and RCP8.5) in combination with the recent five years of growth-stage data from agrometeorological observation stations in the middle and lower reaches of the Yangtze River, changes in heat injury and spatial distribution patterns of single-cropping rice in China during the early(2016–35), middle(2046–65), and late(2080–99) 21 st century were projected by using quantitative estimations. Relative to the reference period(1986–2005), the occurrence probabilities of heat injury to single-cropping rice under different RCP scenarios increased significantly, showing a trend of mild moderate severe. The occurrence probabilities increased with time and predicted emissions, especially the average and maximum occurrence probabilities, which were ～48% and ～80%,respectively, in the late 21 st century under the RCP8.5 scenario. The spatial patterns of the occurrence probabilities at each level of heat injury to single-cropping rice did not change, remaining high in the middle planting region and low in the east. The high-value areas were mainly in central Anhui and southeastern Hubei provinces, and the areas extended to the northwest and northeast of the cultivation area over time. Under the RCP2.6, RCP4.5, and RCP8.5 scenarios, the total area of heat injury to single-cropping rice showed a significant linear increasing trend of 7.4 × 10~3, 19.9× 10~3, and 35.3 × 10~3 ha yr~(–1), respectively, from 2016 to 2099, and the areas of heat injury were greatest in the late21 st century, accounting for ～25%, ～40%, and ～59% of the cultivation area. 相似文献
Glutenite reservoirs are characterized by strong heterogeneity, large thickness, complex rock fabric, and low maturity in terms of structure and composition, which makes the division of sedimentary periods an arduous task. This restricts the exploration and development of oil and gas fields in glutenite reservoirs. Wireline logging signals, which contain rich geological information and record the sedimentary cycle of the strata, are sensitive to changes in the lithologic interface. Moreover, the formation microscanner image (FMI) method provides a complete lithologic profile of the formation and intuitively identifies sequence boundaries, unlike cores and conventional well logs. By integrating mathematical tools based on time–frequency analysis technology of multiscale wavelet transform and FMI as the geological constraint, a sensitive logging curve was selected to delineate the sedimentary cycles of a glutenite reservoir. Optimization of wavelet decomposition parameters was conducted by employing Morlet as the wavelet base, and the scale factors were screened by the direct power spectrum method. Taking the glutenite reservoirs of the Baikouquan Formation in the MA131 well block of the Mahu Sag as the research object, the sedimentary periods of the glutenite body of well MA15 were divided under seismic constraints. The results indicated that the abrupt interface of the wavelet coefficient curve of different scale factors closely corresponded to the interface of sedimentary cycles at distinct levels. This demonstrates the effectiveness of the proposed method. Subsequently, the dynamic time warping algorithm was employed for automatic stratigraphic well correlation. It is concluded that the proposed technique eliminates the overdependence on traditional methods, such as geological and well stratification information, as well as possessing superiority with regard to high precision, better flexibility, and convenient operation.
