Effects of photovoltaic drip irrigation system on kiwifruit yield, quality and environmental benefits in seasonal arid regions of Southwest China

Frequent seasonal droughts in Southwest China, posing a serious threat to sustainable agricultural production. Photovoltaic drip irrigation system (PDIS) integrates photovoltaic power generation, rain-shelter cultivation and precision drip irrigation. Investigating its influence under different photovoltaic (PV) coverage ratios on kiwifruit yield, quality and environmental benefits is conducive to promoting the green, low-carbon and high-quality production of kiwifruit. In 2018 and 2019, 19.8% (T 1 ), 31.6% (T 2 ) and 39.5% (T 3 ) PV coverage ratios were set in kiwifruit orchards of Southwest China, with no PV coverage as a control treatment (CK). Results showed that T 1 treatment had no significant negative effect on kiwifruit yield and physical quality, whereas showed a decreasing trend with coverage increased under T 2 and T 3 treatments. For kiwifruit chemical quality, there were no obvious effects on the accumulation of sugar and acid in kiwifruit under PDIS with different PV coverage ratios. The content of total soluble solids (TSS) and vitamin C (Vc) was significantly increased under T 1 treatment by 5.14∼5.78% and 1.11∼1.40%, respectively. In addition, T 1 treatment can significantly reduce CO 2 emissions by 25.61% during the operation period (2019), and has the best environmental benefits. The comprehensive evaluation value (C i ) of T 1 treatment was 0.725 by the entropy-TOPSIS method and showed the best. Therefore, PDIS with 19.8% coverage is the ideal threshold for optimizing kiwifruit quality and carbon emission reduction without yield loss within the test range of this study. This study provides a theoretical and practical basis for the balance between agricultural production and environmental benefits in the future development of PDIS, which is of great significance to the sustainable agricultural production in seasonal arid regions of Southwest China.