Dead planet, living planet

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 CO 2 , 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 amajor 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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