Tyrrell Christopher D, Chambers Patricia A, Culp Joseph M
Botany Department, Milwaukee Public Museum 800 West Wells Street Milwaukee Wisconsin 53233 USA.
Department of Biological Sciences Marquette University 109 Wehr Life Sciences, 1428 West Clybourn Street Milwaukee Wisconsin 53233 USA.
Appl Plant Sci. 2022 Jul 27;10(4):e11487. doi: 10.1002/aps3.11487. eCollection 2022 Jul-Aug.
Aquatic macrophyte species abundance and nutrient affinity are used in metrics to assess the trophic condition of lakes and rivers. The development of these indices is often regional, with inter-regional comparisons being complicated by the lack of taxonomic overlap. Here, we use a traits-based approach to expand the geographic scope of existing metrics.
We generalized European trophic affinity values using the response of plant growth form to the light-nutrient gradient, then applied these values to sites in Canada. We evaluated the method's performance against the measured total phosphorus concentration (TP).
Free-floating and emergent growth forms were associated with enriched waters (>0.2 mg/L TP), whereas rosette forms were associated with oligotrophic conditions (<0.05 mg/L TP). The responses were longitudinally consistent, and the site scores among indices were highly collinear. Growth form-based scores were more strongly correlated with TP than were species-based scores (0.42-0.56 versus 0.008-0.25).
We leveraged the ecological relationship between increased surface water nutrient enrichment and the dominance of particular aquatic plant growth forms to generalize aquatic plant trophic indices. We demonstrated an approach for adapting species-based indices to plant traits to facilitate a broader geographic application and simpler data collection, which could be used to develop an easily applied trait-based method of assessing water nutrient status.
水生大型植物物种丰富度和养分亲和力被用于评估湖泊和河流营养状况的指标中。这些指标的制定往往具有区域性，由于缺乏分类学上的重叠，区域间的比较变得复杂。在此，我们采用基于性状的方法来扩大现有指标的地理范围。
我们利用植物生长形式对光 - 养分梯度的响应来概括欧洲的营养亲和力值，然后将这些值应用于加拿大的地点。我们根据测得的总磷浓度（TP）评估该方法的性能。
漂浮和挺水生长形式与富营养化水体（TP>0.2mg/L）相关，而莲座状生长形式与贫营养状况（TP<0.05mg/L）相关。这些响应在纵向是一致的，并且各指标之间的站点得分高度共线。基于生长形式的得分与TP的相关性比基于物种的得分更强（分别为0.42 - 0.56和0.008 - 0.25）。
我们利用地表水养分富集增加与特定水生植物生长形式优势之间的生态关系来概括水生植物营养指标。我们展示了一种将基于物种的指标调整为植物性状的方法，以促进更广泛的地理应用和更简单的数据收集，这可用于开发一种易于应用的基于性状的评估水体养分状况的方法。
