Total agricultural R&D spending in developing countries in- creased from USD 3.7 billion (1991) to USD 4.4 billion (2000), or by 1.6 % annually (IFPRI, 2008). This spending was largely driven by Asia, where annual spending increased by 3.3 %. In Africa, agricultural R&D expenditure actually declined slightly, by 0.4 % a year. As a result, the regions of the world are sharply divided in terms of their capacity to use science to promote pro- ductivity growth to achieve food security and reduce poverty and hunger and in a more sustainable manner including re- storing pest or weed infested lands.
Invasive alien species are now thought to be the second-gravest threat to global biodiversity and ecosystems next to habitat de- struction and degradation (Mooney et al., 2000; CBD, 2001; Kenis et al., 2009). The steady rise in number of alien species is pre- dicted to continue under many future global biodiversity scenarios (Sala et al., 2000; Gaston et al, 2003; MA, 2005), although envi- ronmental change may also cause non-alien species to become invasive. Environmental change, (for example rising atmospheric
CO2, increased nitrogen deposition, habitat fragmentation and cli- mate change) may facilitate further invasions (Macdonald, 1994; Malcolm et al., 2002; Le Maitre et al., 2004; Vilà et al. 2006; Song et al., 2008). As invasive or foreign species compose over 70% of all weeds in agriculture (estimated in the USA)(Pimentel et al., 2004), a continued growth in invasive species poses a major threat to food production (Mack et al 2000; MA, 2005; Pimentel et al., 2005; Chenje and Katerere, 2006; van Wilgen et al, 2007).
Restoration attempts will need to address causes for the spread- ing, ranging from the marine spilling of ballastwater in shipping containing numerous exotic and even invasive marine species (UNEP, 2007) to spreading with land transport, to address- ing pollution, landuse patterns and socio-economic variables influencing the initial loss of the ecosystems involved (King et al., 2009). In many cases, re-establishing partial natural cycles, such as storm-burning reducing invasive species like Melaleuca viridiflora on grasslands, but leaving fire-adapted vegetation, could help reduce such invasive pests (Crowley et al., 2009). It is also very well known from agriculture that re-establishment of ecotones or restoring diverse field edges significantly influenc- es the survival of natural pest controlling insects, birds, or that biological control systems (Zhang and Swinton, 2009). This in- cludes among other introducing insects, pathogens, enzymes or establishing natural host plants for pest-predators can effectively reduce infestations such as for example in coffee (Batchelor et al., 2005); tea (Todokoro and Isobe, 2010), banana (Ting et al.,
2010) and mango production (Braimah and van Emden, 2010). Insects or insect-borne diseases in biological control, such the transmission of a pathogenic virus carried by an eriophyid mite Phyllocoptes fructiphilus to control the weed Rambler rose (Rosa multiflora) infesting grazing ranges in China, Japan and Korea, have also proven effective (Smith et al., 2010).
Restoration is also crucial in relation to maintaining soil fertil- ity, restoring degraded soils and reducing compaction (Batey, 2009; Lal, 2009; UNEP, 2009).
It is therefore clear that restoring ecosystem services can involve quite complex measures. Ecosystem services are therefore es- sential parts of the benefits in more organic or diversified eco- agricultural based systems (UNEP, 2009; Sandhu et al., 2010).
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