Sea-level rise will result in increased salinization of coastal areas. Soil salinity is a major abiotic stress that reduces plant growth, yet tolerance to salinity varies across environmental conditions, habitats and species. To determine salinity tolerance of 26 common tropical tree species from Panama, we measured growth, gas exchange and mortality of 3-month-old seedlings subjected to weekly irrigation treatments using five seawater solutions (0 % = control, 20, 40, 60 and 90 % V/V of seawater) for ~2 months. In general, species from coastal areas were more tolerant to increased seawater concentration than inland species. Coastal species such as Pithecellobium unguis-cati, Mora oleifera, Terminalia cattapa and Thespesia populnea maintained growth rates close to those of controls at 90 % seawater. In contrast, inland species such as Minquartia guainensis, Apeiba membranacea, Ormosia coccinea and Ochroma pyramidale showed strong reductions in growth rates and high mortality. Plant height and leaf production also differed greatly between the two groups of plants. Furthermore, measurements of gas exchange parameters, i.e. stomatal conductance and maximum photosynthetic rate, were consistent with the contrasting growth responses of coastal and inland species. Our research reveals a great degree of variation in salinity tolerance among tropical tree species and demonstrates a close relationship between species habitat and the ability to thrive under increasing salt concentration in the soil, with coastal species being better adapted to withstand increased soil salinity than non-costal species.

中文翻译：

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幼苗对26种新热带树种盐度的响应。

海平面上升将导致沿海地区盐碱化加剧。土壤盐分是一种主要的非生物胁迫，会降低植物的生长，但是盐分的耐受性随环境条件，生境和物种的不同而不同。为了确定来自巴拿马的26种常见热带树种的耐盐性，我们使用五种海水溶液（0％=对照，20、40、60和90）测量了每周进行灌溉处理的3个月大幼苗的生长，气体交换和死亡率％V / V的海水）约2个月。一般而言，沿海地区的物种比内陆物种更能耐受海水浓度的增加。沿海物种，例如Pithecellobium unguis-cati，Mora oleifera，Caterapa和Thespesia populnea，在90％的海水中，其生长速率保持接近于对照。相反，内陆物种，如Minquartia guainensis，Apeiba membranacea，Ormosia coccinea和Ochroma pyramidale，显示出生长速度的大幅降低和高死亡率。两组植物之间的株高和叶片产量也有很大差异。此外，气体交换参数的测量，即气孔导度和最大光合速率，与沿海和内陆物种不同的生长响应一致。我们的研究表明，热带树种的耐盐性差异很大，并且表明了物种栖息地与土壤中盐分浓度增加时to壮能力之间的密切关系，而沿海树种比非树种更能适应土壤盐分的增加沿海物种。球果红球菌和欧氏色锥菌显示出生长速率大大降低和高死亡率。两组植物之间的株高和叶片产量也有很大差异。此外，气体交换参数的测量，即气孔导度和最大光合速率，与沿海和内陆物种不同的生长响应一致。我们的研究表明，热带树种的耐盐性差异很大，并且表明了物种栖息地与土壤中盐分浓度增加时to壮能力之间的密切关系，而沿海树种比非树种更能适应土壤盐分的增加沿海物种。球果红球菌和欧氏色锥菌显示出生长速率大大降低和高死亡率。两组植物之间的株高和叶片产量也有很大差异。此外，气体交换参数的测量，即气孔导度和最大光合速率，与沿海和内陆物种不同的生长响应一致。我们的研究表明，热带树种的耐盐性差异很大，并且表明了物种栖息地与土壤中盐分浓度增加时to壮能力之间的密切关系，而沿海树种比非树种更能适应土壤盐分的增加沿海物种。两组植物之间的株高和叶片产量也有很大差异。此外，气体交换参数的测量，即气孔导度和最大光合速率，与沿海和内陆物种不同的生长响应一致。我们的研究表明，热带树种的耐盐性差异很大，并且表明了物种栖息地与土壤中盐分浓度增加时to壮能力之间的密切关系，而沿海树种比非树种更能适应土壤盐分的增加沿海物种。两组植物之间的株高和叶片产量也有很大差异。此外，气体交换参数的测量，即气孔导度和最大光合速率，与沿海和内陆物种不同的生长响应一致。我们的研究表明，热带树种的耐盐性差异很大，并且表明了物种栖息地与土壤中盐分浓度增加时to壮能力之间的密切关系，而沿海树种比非树种更能适应土壤盐分的增加沿海物种。