INTRODUCTION
As indicated in the introductory chapter to this book, knowledge of tropical montane cloud forest (TMCF) occurrence, biodiversity, hydrology, and ecological functioning has increased considerably since the ground-breaking publications of Zadroga (1981), Stadtmüller (1987), and the proceedings of the first international symposium on TMCF held in 1993 in Puerto Rico (Hamilton et al., 1995a). Cloud forests continue to be threatened in several ways, notably by their conversion to pasture and various forms of agriculture, as well as by climatic drying – the numerous hydrological and ecological consequences of which are only poorly understood as yet (Bubb et al., 2004; Mulligan and Burke, 2005a; Pounds et al., 2006; Zotz and Bader, 2009).
The collection of chapters in the present volume further advances our knowledge in the three broad and interrelated areas that were defined in the introduction, viz. (i) cloud forest biogeography and biodiversity, (ii) biophysical and ecological processes, and (iii) management and conservation strategies.
As the recognition of the value of TMCFs as treasure houses of biodiversity and as providers of high-quality water continues to increase, an array of initiatives aimed at their conservation has emerged in recent years, often within a Payment for Ecosystem Services (PES) context (Asquith and Wunder, 2008; Muñoz-Piña et al., 2008; Porras et al., 2008; Garriguata and Balvanera, 2009; Tognetti et al., this volume). Such PES schemes, but also land and forest managers and policy-makers in general, need to determine (amongst others) which forests under their jurisdiction are the most diverse and valuable biologically, which ones provide the best water supplies, which forests are the most vulnerable to climate change or most threatened by encroachment, and which degraded TMCFs have the best chances for rehabilitation.