Universidad Nacional Agraria La Molina. Escuela de Posgrado. Doctorado en Ciencias e Ingeniería Biológicas

The Ash-breasted Tit-tyrant, Anairetes alpinus (Carriker, 1933) (Aves, Tyrannidae), is an endangered and highly specialized bird that inhabits the Polylepis forests (Rosaceae) of Peru and Bolivia. Here, we report 2 new localities in the department of Junín, central Peru, where it was detected in forests dominated by Polylepis canoi, P. rodolfo-vasquezii, and a third undescribed Polylepis species. We conclude that a residential population is the more likely possibility although the possibility of dispersal individuals should also be considered.

Soil infertility is a global problem, amendments such as organic fertilizers and mineral fertilizers are used to improve crop yields. However, these fertilizers contain heavy metals as well as essential mineral elements. The objective of the study was to determine the effect of organic and inorganic fertilizer on the accumulation and health risk of heavy metals in tubers. The plants were cultivated at an altitude of 3970 m using four treatments (poultry manure, alpaca manure, island guano and inorganic fertilizer) and a control group. Soil contamination levels and the degree of metal accumulation in the tubers were also determined. As a result, it was found that the use of inorganic fertilizer and poultry manure increased the values of Cu and Zn in soils, exceeding the recommended standards. The accumulation of heavy metals in potato tubers did not exceed the maximum recommended limits...

Introduction: Monoculture is a significant concern due to its negative impact on soil quality, resource productivity, and agricultural sustainability, particularly in vulnerable communities. This research aims to evaluate high Andean soil management for maca monoculture. Materials and methods: To this end, interviews were conducted with maca farmers adjacent to Lake Chinchaycocha. The effect on soil quality was evaluated based on principal component analysis (PCA), weighted soil quality index (SQIw), and physico-chemical characteristics. Results: The results indicated differences between farmers in agronomic management, monoculture period (from 5 to 9 years), and fallow time (up to 10 years in the best cases). Regarding soil quality, the PCA highlighted boron andtotal nitrogen locations in the same quadrant, with the highest contribution to the analysis. Finally, the SQIw showed that soi...