Nariño is home to a huge variety of dry forests, mountains and high mountain areas, where water sources and high mountain vegetation predominate, known as paramo., All of these are different from each other thanks to the altitudes and climates they thrive in. The mountains are situated in the Río Patía valley, in the north of the department close to the border with Cauca; whereas the high plateaus are located in the Nariño altiplano volcano complex.
Dry forests are distributed at altitudes of between 0 and 1000 masl (3280 ft.), with temperatures higher than 24°C and rainfall of between 700 and 2000 mm (27 to 79 inches) per year, and one or two marked dry seasons (IAvH 1997, 1998b).
In the Miocene, Pleistocene and Holocene in Nariño, the accumulation of ash and other volcanic materials gave rise to great elevations among which are the Chiles (4.760 masl), Cumbal (4.764 masl), and Azufral (4.070 masl) volcanoes, known as the southern volcanic corridor; the Colimba and Cerro Negro paramos and the Galeras volcano (4.276 maal) (14025 ft.) (Rangel, 2000).
Given the particular climatic conditions, in paramo ecosystems the diversity of species for most animal and plant groups is considerably reduced when compared to the mountain forests that surround them.
According to Rangel (2000), the following vegetation is present in this ecosystem:
The presence of numerous sources of water including lagoons and paramos allows for a vast wealth of flora and fauna in the Colombian Massif in the Santuario de Flora y Fauna Galeras, the Páramo de Paja Blanca and in the Chiles, Cumbal and Azufral volcano complex (Corporación Autónoma Regional de Nariño, 2002).
The Nariño volcanos are home to a range of typical paramo flora with at least 84 genuses of Astareceae, among which: Espelletia, Lourtegia, Baccharis, Calea, Chaptalia, Diplostephium, Gynoxys, Loricaria, Oritrophium, Verbesina, Vasquezia, Werneria, Conyza, Hypochoeris, Gnaphalium, Pentacalia, Senecio, Lasiocephalus, Mikania and Munnozia.
The area also houses 53 genuses of Poaceae, such as Calamagrostris, Agrostris, Festuca, Cortadaria and Bromus; 22 genuses of Orchidaceae, such as Alteinsteinia, Elleanthus and Epidendrum; 18 genuses of Apiaceae, such as Niphogeton, Asorella, Areomyrrhis, Hydrocotyle, Eryngium and Ottoba; 15 genuses of Ericaceae, como Befaria, Disterigma, Macleania Pernettya, Gualtheria and Vaccinium; 15 genuses of Scrophulariaceae, such as Calceolaria, Ourisia, Bartsia and Castilleja; 14 genuses of Brassicaceae, such as Cardemine and Draba;11 genuses of Melastomataceae, such as Brachyotum and Miconia; 10 genuses of Caryophyllaceae, such as Drymaria, Colobanthus, Cerastium and Arenaria; 10 genuses of Cyperaceae, such as Oreobalus, Carex and Rhynchospora y 7 genuses of Rosaceae, such as Hesperomeles, Polylepis, Rubus and Acaena.
According to the Nariño Herbarium database there are 1822 plant species organized in 860 genuses and 230 families.
Coffee plantations in the region are not only fundamental for its economy, but also for the conservation and sustainability of the environment. They are home to 33 tree species used for shade, which fulfil a very important role in the optimization of coffee production. The main species among them include: Arrayan (Myrcia popayanensis Hier.), the Yarumo (Cecropia sp.), the Mullo Pava (Oreopanax incisus (Will ex Schull.) Decne.), the Cucharo (Clusia multiflora H.B.K) and the Citrus.
Understanding the biodiversity in areas where specifically coffee is grown instead of other crops, helps us to understand and highlight the challenges and advantages that this product may hold in terms of biodiversity conservation. Shade-system coffee plantations, or coffee farms with interconnected forests are just some of the strategies for optimization that the coffee growers in Nariño use to preserve the biodiversity.