The functional roles of freshwater mussels (Unionida) in tropical systems are poorly understood. We quantified the effects of mussel filtration, excretion and deposition in three anthropogenic tropical systems, i.e. a man-made lake, abandoned mining pool and rice paddy channel. Sinanodonta cf. woodiana (non-native) was present at all three sites, whilst Pilsbryoconcha compressa (native) was present in the channel only. Clearance rates, biodeposition rates and effects on suspended algal pigment and dissolved nutrient concentrations were quantified in controlled, replicated experiments in laboratory tanks with water from original habitats. Clearance rates were generally low and did not explain the high biodeposition rates observed. A considerable proportion of the natural diet of these populations may therefore consist of material that was not available in tanks, i.e. benthic or deposited algae. Deposition rates in lake and channel populations exceeded published rates from temperate and Mediterranean habitats, presumably due to prevalence of non-palatable material and/or higher metabolic rates in tropical systems. The presence of S. cf. woodiana but not P. compressa led to a strong increase in total ammonia nitrogen concentrations and N:P ratios, exceeding estimations from other systems. This study suggests that freshwater mussels play different functional roles in anthropogenic tropical habitats than in temperate systems.

中文翻译：

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高生物沉积率和氮排泄率表明贻贝（双壳类：Unionida）在某些人为热带淡水栖息地中具有很强的功能影响

淡水贻贝（Unionida）在热带系统中的功能作用知之甚少。我们量化了三个人为热带系统中贻贝过滤、排泄和沉积的影响，即人造湖、废弃矿池和稻田渠道。Sinanodonta 比照。woodiana（非本地）存在于所有三个地点，而 Pilsbryoconcha compressa（本地）仅存在于通道中。清除率、生物沉积率和对悬浮藻类色素和溶解营养浓度的影响在实验室水箱中用来自原始栖息地的水进行受控、重复的实验进行量化。清除率普遍较低，并不能解释观察到的高生物沉积率。因此，这些种群的很大一部分自然饮食可能由水箱中没有的物质组成，即底栖藻类或沉积藻类。湖泊和河道种群的沉积率超过了温带和地中海栖息地公布的沉积率，这可能是由于热带系统中非适口物质的普遍存在和/或更高的代谢率。S. cf. 的存在。woodiana 但不是 P. compressa 导致总氨氮浓度和 N:P 比率的大幅增加，超过了其他系统的估计。这项研究表明，淡水贻贝在人为热带栖息地与温带系统中发挥着不同的功能作用。湖泊和河道种群的沉积率超过了温带和地中海栖息地公布的沉积率，这可能是由于热带系统中非适口物质的普遍存在和/或较高的代谢率。S. cf. 的存在。woodiana 但不是 P. compressa 导致总氨氮浓度和 N:P 比率的大幅增加，超过了其他系统的估计。这项研究表明，淡水贻贝在人为热带栖息地与温带系统中发挥着不同的功能作用。湖泊和河道种群的沉积率超过了温带和地中海栖息地公布的沉积率，这可能是由于热带系统中非适口物质的普遍存在和/或更高的代谢率。S. cf. 的存在。woodiana 但不是 P. compressa 导致总氨氮浓度和 N:P 比率的大幅增加，超过了其他系统的估计。这项研究表明，淡水贻贝在人为热带栖息地与温带系统中发挥着不同的功能作用。