Long-term conservation practice in litchi (Litchi chinensis L.) cultivation improves the crop productivity and soil health of degraded lands

A long-term experiment (1995-2021) was conducted on litchi (Litchi chinensis L.) with and without conservation practices, that is, litchi under clean cultivation (LCC) (recommended doses of fertilizers without intercrops and mulch) and litchi with conservation practice (LCP) (micro-site improvement, intercrops, and organic mulching) on degraded lands. The study aimed to evaluate the long-term impact of litchi-based land uses on vegetative growth (plant height, canopy volume, fruit yield, and litter production), soil moisture, biomass production, carbon stocks (CS), and soil qualities (enzyme activities, microbial counts, and soil fertility). The results revealed that LCP improved vegetative growth, yields, and soil moisture over LCC. The total dry biomass was observed 91.6-103.9, stored CS; 43.6-49.4, emitted CS; 7.04-9.40, mitigated CS; 30.1-30.5, soil CS; 35.7-39.9, total CS (soil + vegetation); 65.9-70.5 Mg ha(-1) and carbon dioxide mitigation; 88.3-112.1 Mg ha(-1) in LCC and LCP land uses, respectively. Further, in LCP, beta-glucosidase, acid phosphatase, alkaline phosphatase, and dehydrogenase activities increased by 17.2%, 20.4%, 19.8%, and 24.8%, respectively, in surface soil compared with LCC in 2021. Likewise, the microbial density of bacteria, fungi, and actinomycetes was also observed to be 20.2%, 41.4%, and 19.5% higher, respectively, in LCP land use in 2021 over 2015. Similarly, available N, P, and K increased by 19.9%, 75.3%, and 36.8% under LCP from 1997 to 2021. Hence, litchi-based land use with conservation practices can be advocated to rehabilitate and improve the soil health of degraded lands and enhance ecosystem services in similar edaphoclimatic conditions.