ABSTRACT

The quantification of ecosystem services (ES) remains challenging and can result in biases towards data-rich ES in management. For infaunal bivalves, little quantitative in situ data are available on the ES they provide, and differences between functionally similar species in different habitats are rarely considered. Here, we aimed to measure and compare the ecosystem functions (primary production, nutrient processing, water clearance rates) underpinning water quality regulation in an estuarine intertidal and subtidal bivalve habitat (dominated by Austrovenus stutchburyi and Paphies australis respectively). In situ benthic chambers were used to measure sediment–water column solute fluxes (NH₄⁺, N₂, O₂) and clearance rates which were scaled up (accounting for habitat differences; e.g. inundation period) to daily estimates of ES potential. Higher hourly microphytobenthic productivity, nitrogen recycling and water filtration were observed for the intertidal bivalve habitat. These differences were attributed to environmental differences rather than differences in bivalve biomass. However, scaling these rates to daily ES estimates showed that inundation period will restrict water quality regulating services in the intertidal. Measuring multiple ecosystem functions in situ provides an important step forward in ES quantification and accounts for ecological complexity, feedbacks and highlights habitat-specific differences in how functionally similar species contribute to ES.

摘要

生态系统服务 (ES) 的量化仍然具有挑战性，并且可能导致在管理中偏向于数据丰富的 ES。对于内陆双壳类动物，很少有关于它们提供的 ES 的定量原位数据，并且很少考虑不同栖息地中功能相似的物种之间的差异。在这里，我们旨在测量和比较支持河口潮间带和潮下带双壳类栖息地（分别由Austrovenus stutchburyi和Paphies australis主导）水质调节的生态系统功能（初级生产、养分加工、水清除率）。原位底栖室用于测量沉积物-水柱溶质通量（NH ₄ ⁺, N ₂ , O ₂ ) 和清除率按比例放大（考虑栖息地差异；例如淹没期）到 ES 潜力的每日估计。在潮间带双壳类动物栖息地观察到更高的小型底栖植物每小时生产力、氮循环和水过滤。这些差异归因于环境差异而不是双壳类生物量的差异。然而，将这些比率缩放到每日 ES 估计表明，淹没期将限制潮间带的水质调节服务。就地测量多种生态系统功能在 ES 量化方面向前迈出了重要一步，并解释了生态复杂性、反馈，并强调了功能相似的物种如何对 ES 做出贡献的生境特定差异。