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HUASCARAN BIOSHPERE RESERVE, ANCASH PERU: EVALUATION OF CLIMATE CHANGE SCENARIOS Prepared by Jorge Recharte, Ph.D. The Mountain Institute 1. Purpose of the Assessment The purpose of this study is to contribute a base-line of the natural and human dimensions of change in Huascaran Biosphere Reserve (HBR) in the Ancash Region, Peru. It presents local and global drivers of change in order to explore ideas for research in this biosphere reserve. The dimensions of change that have been selected are those that are identified as priority in the GLOCHAMOST initiative but also specifically relevant to this region of the Andes, i.e.: • Impacts of global change on cryosphere and on grassland and wet land ecosystems in the HBR region. • Impacts on the water regulation services currently provided by the core area of the HBR to upland and lowland users. • Economic, social and institutional transformations taking place at the regional level, mostly as a result of expansion of extractive industries and the rapid social and economic changes it brings. The scope of assessment will be the Santa River watershed, including references to the coastal area which is a dynamic pole of economic growth affecting the uplands. The assessment considers the perspectives of both local communities and researchers concerning the trends of change. For the local perspective we have relied on a survey of 254 farmers (TMI 2010), while the perspective of scientists and practitioners were elaborated during the conference “Adapting to a World Without Glaciers “ (The Mountain Institute 2009). Thus research priorities recommended will reflect not only academic but societal interests. 2. Huascaran Biosphere Reserve: and over view of main drivers of change Huascaran Biosphere Reserve comprises the upper and middle watersheds of two major river systems: Santa River flowing to the west into the Pacific Ocean, and Marañon River flowing east to the Amazon. The southern section of HBR is also the head water of Pativilca and Fortaleza rivers, both flowing to the coast. In both eastern escarpment and in the western Huaylas valley there is a strong vertical variation in climates as one moves from the highlands to the lowlands. For instance in the Santa River watershed precipitation varies from 100 mm at low elevations to 1,500 mm at the highest elevations (5,000 – 6,000 masl) (SEI 2009). There is also a latitudinal precipitation gradient along the Cordillera, with greater precipitation to the south and decreasing precipitation to the north of the range. Seasonally, there is a wet summer and a marked dry winter season. The mountain landscapes comprised by Huascaran Biosphere are themselves the result of both geological and anthropogenic change. This place is a landscape of great beauty protected by Huascaran National Park (HNP). The park was created in 1975 (DS 0622- 75-AG). All subsequent institutional agreements established by the Peruvian government (UNESCO Biosphere Reserve in 1977 and World Heritage Site in 1985) also aim to protect this specific landscape: a mosaic of open range lands, dominated by nearly120 kilometers of snow covered peaks with associated tropical alpine environments, lakes, and remnants Polylepis spp native forests. HNP protects nine of the 18 species of this tree. The lower limit of the core area of HNP is located at an approximate average altitude of 3,800 masl, which at the time of creation of HNP was roughly the altitude above the limit of agriculture. The core area of the reserve extended up to the snow covered peaks, which includes Huascaran peak, Peru’s highest mountain (6769m). This peak is also an icon of national identity. The total area of the HBR is 1,155,800 hectares (Sevillano 2010), quite a large and complex territory. The area of Rio Santa watershed is 11,600 km2) the largest watershed in the Pacific coat of Peru. The Huascaran Biosphere Reserve (HBR) core area is Huascaran National Park (340,000 hectares) which was set to protect the upper ecosystems of Cordillera Blanca, the largest group of tropical glaciers in the world. At the time of creation, Huascaran National Park included approximately 300 lakes, 663 glaciers and 41 main sub-watersheds (Quebradas) draining West to the Rio Santa and the Pacific Ocean andd coast, and East to the Marañon and Amazonas watersehd (20 of these located in the west and 21 in the east). Traditional access and consuetudinary rights of rural communities to pasturelands in the Park as well the organization of mountain tourism and the management of the Park is based on this quebrada territorial units The number of glaciers and glacial lakes have changed dramatically as the glaciers retreat, break and new glacial lakes are formed. The HBR buffer zone is characterized by agricultural landscapes (170,020 hectares) dedicated to traditional crops and livestock of both Andean and European origin. This is an agriocultural landscape inhabited by people of Quechua culture. Virtually all rural people is also fluent in Spanish. These original settlers have occupied the hills above the Huaylas valley for thousands of years since early agriculture developed in the region. The HBR transition zone (645, 780 hectares) extends down to the warm valleys (mostly between approximately 2,800 and 3,200 masl) and then extends upwards to the divortium acquarum of the Negra Range (to the west of Cordillera Blanca) and to the divortium aquarium of the Oriental Range (to the East of the Blanca Range). This transition zone includes some of Peru’s largest mines (e.g. Antamina) and the second most productive gold mine of the country (Pierina) and several smaller mines, including some that have legal rights to extract minerals (although not to process it inside the Park). Pre-historic origin of present day landscape The processes of landscape change originated with human groups of hunters and gatherer that roamed the region for deer and guanaco (Lama guanicoe) from 12,500 BC, during a cold and wet climate period of glacial advance in the Andes (E.P. Lanning 1967; T. Lynch 1971). Indirect archeological evidence (stone tools to process wood) indicates wooded valleys and larger Polylepis spp, Buddleia, Gynoxis stands. Hunters migrated seasonally between the warmer valley and the colder puna. By 7,500 BC hunters had moved up as the glaciers retreated, seasonally occupying caves at ~4,500 masl (e.g. Quishqui Puncu cave in Huaylas inside the HBR or Lauricocha cave near the southern border of HBR). Burning the puna vegetation to manage wild herds of guanaco and subsequent domestication was initiated in this period (E.P. Lanning 1967). The co-evolution of the glaciers, alpine and forest landscapes of the HBR is subject to much debate, as summarized by Sevillano (2010). On the one hand it is postulated (Fjeldsa, J. and M. Kessler (1991)) that Polylepis spp forests dominated the alpine areas of the Andes in general and were the climax vegetation up to or near the snow line limit. Thus the remaining forests in Huascaran National Park would be relicts (it is estimated that extant Polylepis spp forests are about 2% of their original extension at the scale of Peru). An alternative position proposes that the current fragmentation of forests responds to a natural island-like evolution associated with glacial expansion and recession across large geological times (e.g. Van der Hammen 1986 cited in Sevillano 2010). A third position is that the current distribution of forests is the outcome of both a natural island like distribution associated with adaptation to micro-climates as well as the result of anthropogenic pressures (e.g. Young y Leon, 1995 cited in Sevillano 2010). The Cordillera Blanca is thus a cultural landscape that co-evolved with humans over the last 12,500 years. Within the territory of the HBR there are several monumental remains that provide archeological evidence not only of the rural economy of farmers (e.g. terraces) but also of their ceremonial nature and thus of society’s relationship to the mountains. Example of places which were sacred include for example Huaricoto or La Galgada in the main valley of the western escarpment, or Chavín de Huántar in the eastern flank (Ibarra Asencios 2003). A complex network of mountain roads crossing the Cordillera developed over time, facilitating the flow of people, materials and ideas within the valley, across the mountains and with other regions of Peru. Some of the routes associated with pre-hispanic ceremonial centers were in fact part of large pilgrimage routes. Some of these ancient pilgrimage routes crossing the Cordillera are now both tourist trekking routes and are in use by mountain communities (e.g. Uquian-Ututo- Shongo (Olleros-Chavín); Santa Cruz-Huaripampa, Llanganuco-Morococha, Ulta- Potaca, Honda-Juitush (Plan Maestro PNH 2002). These routes were also part of larger pilgrimage routes that connected major ceremonial centers at hundreds of kilometers away, like for example the ceremonial centers of Huánuco Pampa, beyond the southern end of the HBR, with Huanacaure in Cuzco (Astuhuaman 2008). As noted, landscapes in the HBR region have changed over time as a result of both major climatic shifts and human land use influence, however the pace of changes in the present day landscapes is faster and broader than before. Present day landscape The following example of land cover types at Quebrada [sub-watershed] Quillcayhuanca (J. Chang 2002) illustrates the typical landscape that is protected by the core area: a combination of open range grasslands (42%) with dominant species such as Festuca dolichopylla, Stipa ichu and Calamagrostis spp.; snow covered peaks (32%); native forest, predominantly “queñual” (Polylepis spp.) (15%); bushes, including associated bunch grasses and herbs (6%); and wetland ecosystems of the alpine area (2%). It should be noted the importance of Polylepis spp forests from a conservation stand point since the Huascaran National Park (HNP harbors probably some of the largest forest fragments remaining in Peru and in the Andes.