**3. Peri-urban clusters**

Metropolitan centres and other important regional capital centres and economic centres have experienced major population growth rates and areal expansions. This has resulted in a massive planned or uncontrolled urban–rural interface of a wider surrounding region and to the emergence of major peri-urban clusters ([21]: 184-188 and 191-192). While this urbanization may bring to the region new housing, attractive landscape amenity sites for affluent urbanites (so-called *parcelas de agrado* and *ciudades valladas*, **Figure 6**), new employment opportunities or enhanced infrastructures, the negative impacts of this "urban invasion" often prevail ([24]: 239). Land speculation and soaring land prices are threatening the survival of small-scale agriculture and the traditional rural livelihoods by a consumption of often fertile irrigated agricultural land and by diverting the water resources from irrigating the fields to a use for urban households and commercial needs. Driven away by this urbanization process, agricultural smallholders are faced with the options of incorporating themselves into the urban agglomeration, to intensifying land use on their remaining plots or to seeking alternative new agricultural areas. Haller [24] has found that farmers in the Huancayo basin have expanded or intensified field cultivation in the higher *suni* [25] altitudinal belt (3500 to 4000 m), a marginal and poorly accessible agricultural zone with steep and nonirrigated slopes not suitable for year-round cultivation. Using the example of the regional city of Huancayo and the lower Shullcas Valley, Haller and Córdova-Aguilar [26] have demonstrated that urbanization puts pressure on agrarian land use, endangers the environmental integrity of the region and impacts the Huaytapallana Regional Conservation Area.

In the Andes, these agglomerations of a dynamic and multifunctional urban– rural continuum represent the most important areas of population growth, land use

**Figure 6.** *Ciudad Vallada Piedra Roja, Chile (Borsdorf and Stadel 2015).*

conversion and excessive densities of buildings and infrastructural developments. These newly emerging or rapidly expanding clusters are facing the challenge of integrated and effective regional planning and policy actions that attempt to regulate the nature of the growth processes, to recognize the interests of urban and rural stakeholders and to harmonize economic goals with ecosystem services.
