Mixing Green Manure With Native Seeds in the Same Row Enhances Species Establishment in Restoration Areas of the Brazilian Cerrado

Aims

This study investigates the effectiveness of different spatial arrangements of green manure and native species in promoting native seedling emergence and reducing invasive grass cover in restoration efforts, particularly within agricultural landscapes.

Location

Cerrado biome (savanna), Brazil.

Methods

We tested four experimental setups by direct seeding: (1) native species only (control), (2) native species and green manure mixed in the same row (N + GM [mixture]), (3) green manure and native species planted in separate rows (N + GM [rows]), and (4) native species intercropped with wider strips of green manure (N + GM [strips]). We evaluated richness, seedling abundance, invasive grass cover, and cost-effectiveness 540 days (a year and a half) post planting.

Results

The N + GM (mixture) treatment yielded the best cost-effectiveness, highest species richness (three species) and seedling abundance (10,267 individuals/ha), along with the lowest invasive grass cover (50%). Hymenaea stigonocarpa Mart. ex Hayne and Astronium fraxinifolium Schott ex Spreng had the highest emergence rates across all treatments. However, green manure alone did not entirely prevent invasive grass, requiring further weed control. N + GM (rows) showed the lowest cost, but should be considered only with ongoing maintenance.

Conclusions

Mixing green manure with native species in the same row (N + GM [mixture]) is a practical and cost-effective method for increasing native species emergence in the early stages of restoration, particularly in agricultural settings, where mechanized planting is feasible.