This study aims to evaluate the construction mode of small-scale farmland water conservancy using secondary data from the China statistical yearbook (2000–2019), which was simply and statistically computed. To put it briefly, the simple linear regression model was used to analyse the number of small-scale reservoirs and irrigated areas relative to their capacities and effectiveness. The results showed that the number of small-scale reservoirs increased by 122.2 units of their capacity and the number of small-scale irrigated areas increased by 6.8 units of their effectiveness. The present study introduces the simple linear regression model and accounts for how the number of the small-scale reservoirs and irrigated areas has increased (the total number of reservoirs was 83,260 in 2000 and 98,822 in 2018) relative to their capacity and effectiveness, respectively. Of course, the capacity of water harvesting and the effectiveness of irrigated areas have shown a linear increase over time. Between 2000 and 2019, the capacity increased from 3842 to 7117 for large-scale reservoirs, from 746 to 126 for medium-scale reservoirs, and from 594 to 710 for small-scale reservoirs and their ranges were 3.2, 380, and 116, respectively. Furthermore, the findings of this evaluation provide insights for making decisions on water conservancy interventions.

In this paper, the Al-K2ZrF6 reaction system was used to prepare in-situ Al3Zr/AA6082 particle-reinforced aluminum matrix composites by electromagnetic stirring melt reaction method, and the friction stir welding technology was used to weld the plate. The microstructure and mechanical properties of the welded joints were studied when the rotating speed was 14000 rpm and the welding speed was 30, 50 and 70 mm/min respectively. The results show that the weld forming quality and tensile properties of the FSW joints with welding parameters of 14000 rpm and 50 mm/min are the best, the tensile strength is 142(±0.5) MPa and the elongation is 8.2%. SEM analysis shows that the particle size of the reinforcing phase in the base metal is refined to about 5-10 μm, while that in the NZ is about 1-5 μm. The grain size in the HAZ is about 20-30 μm and in the NZ is about 5-10 μm. EBSD analysis shows that the proportion of low-angle grain boundary in the NZ is 59.7% and of recrystallized grain structure is 23.65%, while the proportion of small-angle grain boundary in the HAZ is 24.35% and of recrystallized grain structure is 37.18%. It provides theoretical and experimental basis for the forming and application of friction stir welding of the composite.