El presente trabajo informa los resultados del estudio de la liquenobiota de la localidad andina de Pueblo Libre, (09º05'30''-09º10'15'' S y 77º47'30''-77º52'50'' W) en Huaylas, Ancash, Perú. Las colectas se realizaron desde los 2200 hasta los 4450 m de altitud. El presente trabajo da a conocer 38 especies, agrupadas en 29 géneros y 17 familias y además del grupo imperfecto. Se presentan claves para familias, géneros y especies. Para cada especie se presenta una descripción macroscópica y microscópica y de reacción química, asimismo se menciona el hábitat y material examinado.

The use of lichens as bioindicator are widely recognized, especially to know environment quality in a specific zone. This paper assess the lichens as bioindicators of air pollution in the mining environmental liability Santo Toribio, Áncash, Perú. Two zones were studied with similar habitats characteristic, but differentiated in the presence of environmental impact, one called Passive Zone and other Control zone; in the first 8 stations were stablished and in the second 1; 108 sampling points were evaluated. In order to know the levels of air pollution by lichens a study of species richness was carried out. Index of Atmospheric Purity (IAP) was calculated and heavy metals were analyzed. In the case of IAP, the protocol originally used in phorophytes (trees) was adapt to rocky substrates due to the limited timberline in the area; the species used for the analysis of heavy metals by means of environmental scanning electron microscopy (ESEM) was Usnea durietzii (Motyka, 1937). The study found 42 lichen species distributed in 15 families and 27 genera being mostly crustose type. The lowest value of richness species and IAP and high concentration of heavy metals found in the Passive Zone , reflecting the high levels of air pollution and the efficacy of lichens as bioindicadores of air pollution.

Grasslands in the Andean highlands plateau of southern Peru have been considered as a single and homogeneous dry habitat also known as Puna. However, in some regions, a highest rainfall regimen is found, and the name of wet puna has begun to be used by some authors. Since no studies have been carrying out specifically to test if dry and wet puna are different ecological units, we chose two representative localities of each one of these habitat to evaluate assemblages of bird and mammal communities and their continuity or independence between these apparently similar habitats. Our results suggest that wet puna has different mammal diversity than dry puna, and a heterogeneous bird community with species that have been previously reported exclusively in paramo or exclusively in puna. In spite of the apparent uniform flora in the Andean highlands of South Peru, data suggest that rainfall regimens produce a mosaic of habitats that will be determining ecological barriers for terrestrial mammals, in particular for small mammals. Key words: Andean grasslands, Andean plateau, Cuzco, Oriental Cordillera, paramo, puna, Puno. ResumenLos Pajonales de los Andes del sur del Perú, también conocidos como Puna, son considerados como hábitats homogéneos y secos. Sin embargo, en algunas regiones se encuentra un alto régimen de precipitaciones y algunos autores han empezado a usar el nombre de Puna Húmeda. Hasta la actualidad no se vienen realizando estudios específicos para probar si la Puna Húmeda y Seca son dos unidades ecológicas diferentes. Se escogieron dos localidades representativas de cada uno de estos hábitat para evaluar la estructura de las comunidades de aves y mamíferos y su continuidad o independencia entre estos hábitat aparentemente similares. Los resultados sugieren que la Puna Húmeda tiene una diversidad de mamíferos diferente a la de la Puna Seca, y una comunidad de aves heterogénea con especies que vienen siendo previamente reportadas como exclusivas de Páramo o de Puna. A pesar de la aparente uniformidad de la flora en los Andes del sur del Perú, la información sugiere que los regimenes de precipitaciones producen un mosaico de hábitat que estaría determinando barreras ecológicas para mamíferos terrestres, en particular para pequeños mamíferos.

The lichens are knowlegde like bioindicators of the air quality, because have wide distribution, be long live, immobile, by lacking root and cuticle. The study presents the taxonomy, ecology and lichenography of the lichen Heterodermia leucomela (L.) Poelt, for its high potential as a bioindicator of air quality. The characters of lichen are: foliose biotype, gray and grows on moss; to live over the 200 to 3500 msnm. It is register for departaments of Ancash, Arequipa, Huanuco, Lima and La Libertad; and in Lima is report in the hill of Amancaes, Lachay, Lucumo, Lurin and Mangomarca.