Search Results (2)

The long-term use of polyethylene mulch (PEM) films can cause plastic film residual pollution that has an adverse effect on soil health and crop quality. To address this issue, poly(butylene adipate-co-terephthalate) (PBAT), an aliphatic–aromatic copolyester, is widely used in the production of commercially biodegradable plastic mulch (BDM) films. The use of BDMs can alleviate soil plastic pollution and reduce the labor cost of retrieving plastic film residues from the field. The effects of BDM and PEM on the agronomic and nutritional quality traits of cabbage cultivar ‘Sugan No. 35’, as well as the physicochemical properties and microbial communities of the soil were analyzed during two consecutive years of the experiment. No significant difference was observed in the cabbage agronomic and nutritional quality traits among three mulching treatments. Nonetheless, the mulching and degradation of BDM reduced the pH value and increased the organic matter content of the soil samples compared with PEM mulching. In the soil bacterial and fungal communities, Proteobacteria and Ascomycota were the most abundant bacterial phylum and fungal phylum across all the soil samples, respectively; the use of BDM increased the relative abundance of soil Proteobacteria and Ascomycota compared with PEM mulching. The overall cost of BDM mulching was much lower than that of PEM mulching during the cabbage production. Full article

A self-propelled machine for combined potato harvesting and residual plastic film retrieval is presented in this paper. The machine was designed collaboratively and built at the College of Mechano-Electronic Engineering of Gansu Agricultural University. It is intended for slow slope and horizontal terraces in hilly and mountainous areas of Northwest China, where regular-size harvesters cannot operate. The machine can realize the combined operations of potato digging, potato separation from soil and plastic film, potato collection and bagging, and residual plastic film retrieval. Through engineering analyses, the main systems of the machine were calculated, and their operating parameters were estimated. These include the digging and lifting device, the potato–plastic-film separation device, and the residual plastic film retrieval device. Field tests were performed at a 0.5 m/s driving speed of the machine, while the linear speed of the lifting chain of the digging and lifting device was 1.5 m/s, the tilting angle of the conveying chain of the potato and plastic film separation device was 50°, its linear speed was 0.6 m/s, and the linear speed of the lifting screen of the circulating lifting device was 0.7 m/s. With these settings, the average productivity of the machine was 0.12 ha/h. The loss rate, damage rate, and potato bruising rate were 1.8%, 1.4%, and 2.8%, respectively; the potato impurity rate was 3.6%; and the residual plastic film retrieval rate was 83%—all above industry standards. This research provides a solution to the problem of mechanized potato harvesting and plastic mulch retrieval on small, slopped plots of land in Northwest China and in other parts of the world where similar conditions exist. Full article