The contradiction between population and cultivated land has always been an urgent global problem, and one that is particularly prominent in China. Based on the spatial–temporal evolution of cultivated land, this paper discusses the human–land contradiction and its development trend. Then, according to the threshold of human–land contradiction and different protection objectives, the priority protection area of cultivated land was simulated. The results showed that: (1) the cellular automata (CA)–Markov model is suitable for the study area. The cultivated land in the study area increased at a rate of 4.40 sq km per year; (2) the spatial and temporal change in the cultivated land in Songpan was the largest. The center of gravity of cultivated land is moving to the northeast, and the moving rate is increasing year on year; (3) 90% of the study area was in the human–land coordination and the change in the ratio of accumulation and cultivation in some areas (such as Songpan) is increasing, making the human–land contradiction worse; (4) under a protection target of 25–100%, the priority protection area of cultivated land increased from 2.05 × 10³ km² to 3.46 × 10³ km², and the patch aggregation degree was strengthened. This study was of great significance for optimizing the distribution of cultivated land and promoting the sustainable development of land resources.

For optimizing the reaction conditions of 2-methyl-6-ethylaniline (MEA) degradation catalyzed by horseradish peroxidase (HRP), a response surface methodology with three factors and three levels was used in this research to establish a regression model, a ternary quadratic polynomial, in order to analyze temperature, H₂O₂ concentration and pH effects on MEA removal efficiency. The results showed that the regression model was significant (p < 0.0001), fitted well with experimental data and had a high degree of reliability and accuracy, and the data were reasonable with low errors. By analyzing interactions and solving the regression model, the maximum MEA removal efficiency was 97.90%, and the optimal conditions were defined as follows: pH 5.02, H₂O₂ concentration 13.41mM, and temperature 30.95 °C. Under the optimal conditions, the average MEA removal efficiency obtained from the experiments was 97.56%. This research can provide reference for the treatment of actual acetochlor industrial wastewater.