Bivalve aquaculture may provide a variety of ecosystem services including nitrogen extraction from estuaries, which are often subject to excess nutrient loading from various land activities, causing eutrophication. This nitrogen extraction may be affected by a combination of various non-linear interactions between the cultured organisms and the receiving ecosystem. The present study used a coupled hydro-biogeochemical model to examine the interactive effects of various factors on the degree of estuarine nutrient mitigation by farmed bivalves. These factors included bay geomorphology (leaky, restricted and choked systems), river size (small and large rivers leading to moderate (105.9 Mt N yr^-1) and high (529.6 Mt N yr^-1) nutrient discharges), bivalve species (blue mussel (Mytilus edulis) and eastern oyster (Crassostrea virginica)), farmed bivalve area (0, 10, 25 and 40% of estuarine surface area) and climate change (water temperature, sea level and precipitation reflecting either present or future (Horizon 2050) conditions). Model outputs indicated that bivalve culture was associated with the retention of nitrogen within estuaries, but that this alteration of nitrogen exchange between estuaries and the open ocean was not uniform across all tested variables and it depended on the nature of their interaction with the bivalves as well as their own dynamics. When nitrogen extraction resulting from harvest was factored in, however, bivalve culture was shown to provide a net nitrogen removal in the majority of the tested model scenarios. Mussels provided more nutrient mitigation than oysters, open systems were more resilient to change than closed ones, and mitigation potential was shown to generally increase with increasing bivalve biomass. Under projected future temperature conditions, nutrient mitigation from mussel farms was predicted to increase, while interactions with the oyster reproductive cycle led to both reduced harvested biomass and nutrient mitigation potential. This study presents the first quantification of the effects of various biological, physical, geomorphological and hydrodynamical processes on nutrient mitigation by bivalve aquaculture and will be critical in addressing questions related to eutrophication mitigation by bivalves and prediction of possible nutrient trading credits.

双壳贝类水产养殖可提供多种生态系统服务，包括从河口提取氮，这些服务往往受到各种陆地活动造成的过多营养负荷的影响，导致富营养化。这种氮提取可能受到培养的生物体和接收生态系统之间各种非线性相互作用的影响。本研究使用耦合水生地球化学模型来检验各种因素对养殖双壳贝类河口养分缓解程度的交互影响。这些因素包括海湾地貌（渗漏、受限和阻塞的系统）、河流规模（小型和大型河流导致中等（105.9 Mt N yr ^-1）和高（529.6 Mt N yr ^-1）养分排放）、双壳类物种（蓝色贻贝 (贻贝) 和东部牡蛎 (牡蛎))、养殖双壳贝面积（河口表面积的 0、10、25 和 40%）和气候变化（反映当前或未来（Horizo​​n 2050）条件的水温、海平面和降水）。模型输出表明，双壳贝类养殖与河口内氮的保留有关，但河口和公海之间氮交换的这种变化在所有测试变量中并不统一，它也取决于它们与双壳贝类相互作用的性质作为他们自己的动力。然而，当将收获产生的氮提取考虑在内时，双壳贝类养殖在大多数测试模型情景中显示出提供净氮去除。贻贝比牡蛎提供更多的营养缓解，开放系统比封闭系统更能适应变化，随着双壳类生物量的增加，减缓潜力普遍增加。在预计的未来温度条件下，贻贝养殖场的养分缓解预计会增加，而与牡蛎繁殖周期的相互作用导致收获生物量和养分缓解潜力的减少。本研究首次量化了各种生物、物理、地貌和水动力过程对双壳贝类水产养殖养分缓解的影响，对于解决双壳类富营养化缓解相关问题和预测可能的养分交易信用至关重要。而与牡蛎繁殖周期的相互作用导致收获的生物量和养分缓解潜力减少。本研究首次量化了各种生物、物理、地貌和水动力过程对双壳贝类水产养殖养分缓解的影响，对于解决双壳类富营养化缓解相关问题和预测可能的养分交易信用至关重要。而与牡蛎繁殖周期的相互作用导致收获的生物量和养分缓解潜力减少。本研究首次量化了各种生物、物理、地貌和水动力过程对双壳贝类水产养殖养分缓解的影响，对于解决双壳类富营养化缓解相关问题和预测可能的养分交易信用至关重要。