Influence of tree species on soil physicochemical composition, macrofauna, and forage production

Abstract

The expansion of livestock farming has had negative environmental impacts, such as biodiversity loss, soil compaction, and greenhouse gas emissions. Silvopastoral systems (SPS), which integrate forest species and grazing, are an alternative to mitigate these effects. The main objective of this research was to analyze the influence of tree species with seasonality in agroecological conditions in the Peruvian Amazon on physicochemical parameters and soil macrofauna, as well as pasture nutritional quality. A completely randomized block experimental design with a bifactorial arrangement (4A × 2S, where factor A represents tree species and open field and factor S, represents seasonality) was applied. The results revealed that, in winter, the forest species Alnus acuminata and Pinus patula increased soil organic matter by 60.84 % and 27.41 %, respectively, and electrical conductivity increased by 100 % and 143.75 %. A significant reduction in clay and a 60.13 % increase in sand were also observed during this season. Regarding forage yield, the forest species Cupressus sp. Showed the highest values in winter (90.24 t/ha), exceeding summer yields by 78.85 %, while Pinus patula yielded more in summer. In terms of biodiversity, alder had the highest diversity index (H' = 1.43) in summer, with lower dominance and greater equity. Bromatological analyses indicated that alder and cypress had higher protein contents in summer, with decreases of 33.81 % and 23.67 % in winter. The results indicate that SPS, depending on the tree species and season, can improve soil quality, increase forage productivity, and promote greater biodiversity.

Keywords

• Alnus acuminata
• Cupressus sp
• Pinus patula
• Biodiversity
• Agroforestry
• Macrofauna