Wetlands are highly productive ecosystems, providing a number of functions (products and services) that are of value to people. The open-access nature and the public-good characteristics of wetlands often result in wetlands being undervalued in decisions relating to their use and conservation. There is now a substantial literature on wetland valuation, including two meta-analyses. These meta-analyses examine subsets of the available wetland valuation literature, focusing on temperate wetlands, a limited set of wetland functions, and a limited set of valuation techniques. We collect over 190 wetland valuation studies, providing 215 value observations, in order to present a more comprehensive meta-analysis of the valuation literature that includes tropical wetlands (e.g., mangroves), estimates from diverse valuation methodologies, and a broader range of wetland functions (e.g., biodiversity value).We also aim for a more comprehensive geographical coverage. We find that socioeconomic variables, such as income and population density, that are often omitted from such analyses are important in explaining wetland value. We also assess the prospects for using this analysis for out of sample value transfer, and find average transfer errors of 74%, with just under one-fifth of the transfers showing errors of 10% or less. This overall performance is, however, dominated to a considerable extent by transfer to small sites. The performance of value transfer for medium to large wetlands on average shows transfer errors smaller than 30%.

All seagrasses are rhizomatous plants that grow by reiteration of a limited set of modules. Their past growth history can therefore be reconstructed from the scars left by abscised leaves and flowers on the long-lived rhizomes or the seasonal slgnals Imprinted in the frequency and size of their modules. We provide here the basic foundations and assumptions of these reconstruction techniques and the calculations involved in their application. We then show their reliability and potential to quantlfy an array of ecological processes, such as plant demography, leaf and rhlzome production, flowering ~ntensity, and seagrass responses to anthropogenic perturbations, based on our recent studies of Mediterranean, Caribbean and Indo-Pacific seagrass species. Reconstruction techniques have also proven useful in demonstrating the role of seagrasses as tracers of sedlment movement over seagrass beds and the rates of colonisation and expansion of seagrass patches. These reconstruction techniques should provide a powerful tool to improve our knowledge of seagrass species and populations from remote areas based on a single or just a few visits This should, therefore, allow us to sample many seagrass meadows using limited resources, thus generating a strong foundation for the study of comparatlve seagrass ecology and testing of theories previously applied to terrestrial plant populations.

Leaf product~on, shoot demography and rhlzome growth and branchlng were quantified for the common seagrass specles In a muted seagrass bed on the Bollnao leef flat (Luzon The Ph~llp-plnes) to assess the contribution of these s p e c~e s to canopy maintenance meadow biornass and productlvlty We tested the hypothesis that seagrass growth rates correlated negatively with shoot size and a g e when compared across specles, and found that shoot recruitment leaf turnover and honzontal rhizome elongation and branchlng rates were lower for s p e c~e s wlth older and larger shoots ~Vedian shoot ages for the short-llved species were generally less than a year, those for the longer-llved Enhalus acoroides ( L f ) Royle and Thalassla hempnchii (Ehrenb ) Aschers were sllghtly more than 1 5 yr The oldest E acoroldes had almost reached 10 yr Generally, shoot mortality and ~e c r u l t m e n t balanced each other falrly well The rhizomes of longer-lived E acoroldes and T hempnchli elongated at rates of 5 and 21 cm yr-l, respectively, and those of the short-llved Synngodi~lm isoetifobum (Aschers ) Dandy and Halophila ovalls (R Br ) Hook f at rates of 135 and 141 cm yr-' Vertical shoot elongat~on ranged from 2 to 13 cm shoot ' yr ' and was not correlated wlth size or a g e The meadow had a total bion~ass of 624 g dry wt (DW) m-' (roots excluded), to whlch the larger and longer-llved specles 7 hempnchil and E acoro~des contnbuted substantially (52 and 37%, respectively) Leaf product~on dominated total annual ploductlvity, constituting 91 % of 2143 g DW m ' yr ' (roots excluded) thls productlvlty was malnly due to T hempnchli (74 %), and not to the oldest and slowest-growing E acoroides ( 1 0 % ) KEY WORDS Troplcal seagrasses Shoot life spans Recruitment and mortal~ty P~o n e e r vs cllmax specles Allon~etry

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Meta-analysis of case studies has become an important tool for synthesizing case study findings in land change. Meta-analyses of deforestation, urbanization, desertification and change in shifting cultivation systems have been published. This present study adds to this literature, with an analysis of the proximate causes and underlying forces of wetland conversion at a global scale using two complementary approaches of systematic review. Firstly, a meta-analysis of 105 case-study papers describing wetland conversion was performed, showing that different combinations of multiple-factor proximate causes, and underlying forces, drive wetland conversion. Agricultural development has been the main proximate cause of wetland conversion, and economic growth and population density are the most frequently identified underlying forces. Secondly, to add a more quantitative component to the study, a logistic meta-regression analysis was performed to estimate the likelihood of wetland conversion worldwide, using globally-consistent biophysical and socioeconomic location factor maps. Significant factors explaining wetland conversion, in order of importance, are market influence, total wetland area (lower conversion probability), mean annual temperature and cropland or built-up area. The regression analyses results support the outcomes of the meta-analysis of the processes of conversion mentioned in the individual case studies. In other meta-analyses of land change, similar factors (e.g., agricultural development, population growth, market/economic factors) are also identified as important causes of various types of land change (e.g., deforestation, desertification). Meta-analysis helps to identify commonalities across the various local case studies and identify which variables may lead to individual cases to behave differently. The meta-regression provides maps indicating the likelihood of wetland conversion worldwide based on the location factors that have determined historic conversions.