Page - 367 - in Biodiversity and Health in the Face of Climate Change

367 contributing to local livelihoods and the survival of hundreds of plant and animal species (Dudley et  al. 2010). Elsewhere, natural ecosystems, including wetlands and grasslands, play a key role in reducing pollution levels and particulate matter in water, as well as absorbing storm-water run-off. Wetlands can reduce high levels of nutrients, and some water plants concentrate toxic materials in their tissues, thus purifying surrounding water. For example, Florida’s cypress swamps remove 98% of all nitrogen and 97% of all phosphorus from wastewater entering the wetlands. Natural wetlands also help dilute contaminants derived from upstream agriculture, thus ameliorating water quality in agriculturally-dominated landscapes in the world’s major river basins (Dudley and Stolton 2003). However, maintaining healthy ecosystems to provide these environmental bene- fits, such as adequate water supplies for agriculture and domestic use, will become an increasingly challenging issue with climate change, habitat degradation and bio- diversity loss, especially in the developing world (Dudley et  al. 2010; WCPA 2011). In South Africa, for instance, invasive alien species are estimated to affect ten mil- Box 16.1: Protected Areas Providing Clean Water for Domestic Use In many parts of the world adequate supplies of potable water depend on pro- tected areas: • Kerinci Seblat National Park in Indonesia protects the head waters of two of Sumatra’s major rivers, the Musi and the Batanghari, which provide downstream water supplies for major cities such as Jambi, Padang and Palembang, as well as millions of hectares of irrigated farmlands. • In Ecuador, about 80% of Quito’s 1.5  million residents receive drinking water from two protected areas in the Andes. • The 22,000 hectare Te Papanui Conservation Park, in New Zealand’s Lammermoor Range, provides the Otago region with essential water flows valued at NZ$ 93  million for urban water supply. • Protected areas are particularly valuable in water resource terms where they occur upstream of large population centres in dry environments. The Cholistan Wildlife Sanctuary upstream of Karachi, Pakistan (population 18  million), for example, provides water services estimated at US$ 100  million per year to the downstream population. • Six reservoirs in the Catskills Mountains provide water to nine million people in the New  York City area. Careful management of the landscape and protected areas provide good quality water through the largest unfil- tered water supply in the USA, with a few million dollars spent on water- shed protection saving billions of dollars in infrastructure costs for filtration. Sources: Dudley et  al. 2010; World Bank 2010. 16 Nature-Based Solutions and  Protected Areas to  Improve Urban Biodiversity…