Nutrient limitation of periphyton growth in arctic lakes in south-west Greenland
Nutrient limitation of periphyton growth in arctic lakes in south-west Greenland
复制标题
DOI：
10.1007/s00300-014-1524-8
复制
发表时间：
2014-09-01
期刊：
影响因子：
1.7
通讯作者：
Anderson, N. J.
中科院分区：
文献类型：
--
作者：
Hogan, E. J.;McGowan, S.;Anderson, N. J.
许多北极湖泊是贫营养系统，其中光养生长受营养供应控制。最近的人为营养物负荷与北极几个湖泊的生物和/或物理化学变化有关。营养限制(氮（N)，磷(P)或N + P）的变化及其对藻类群落生长和组成的相关影响经常被报道。格陵兰岛西南部的Kangerlussuaq地区形成了一个主要的湖区，被认为很少受到直接的人为干扰。然而，污染物N的远程运输现在正在到达格陵兰岛，并且假设从内陆冰盖边缘到海岸的降水梯度也可能导致N沉积增加。在整个地区的三个湖泊：冰盖边缘、内陆（靠近Kangerlussuaq）和海岸（靠近Sisimiut）部署了原位营养生物测定，以确定湖泊的营养限制，并调查营养物质对周围植物生长和群落组成的任何影响。不同湖泊的营养限制不同：N限制（冰原边缘）、N和P限制（内陆）和N + P共同限制（海岸）。探讨了氮供应变化、冰物候、季节性藻类演替、群落结构和物理湖泊等因素作为解释湖泊差异的机制。北极湖泊的营养限制和相关的生态影响变化很大，即使在小的地理区域也是如此。在这个高度敏感的地区，未来的环境变化情景极有可能显著改变营养限制；反过来，可能会严重影响湖泊的结构和功能。
Many arctic lakes are oligotrophic systems where phototrophic growth is controlled by nutrient supply. Recent anthropogenic nutrient loading is associated with biological and/or physico-chemical change in several lakes across the arctic. Shifts in nutrient limitation (nitrogen (N), phosphorus (P), or N + P) and associated effects on the growth and composition of algal communities are commonly reported. The Kangerlussuaq region of south-west Greenland forms a major lake district which is considered to receive little direct anthropogenic disturbance. However, long-range transport of pollutant N is now reaching Greenland, and it was hypothesised that a precipitation gradient from the inland ice sheet margin to the coast might also deliver increased N deposition. In situ nutrient bioassays were deployed in three lakes across the region: ice sheet margin, inland (close to Kangerlussuaq) and the coast (near Sisimiut), to determine nutrient limitation of lakes and investigate any effects of nutrients on periphyton growth and community composition. Nutrient limitation differed amongst lakes: N limitation (ice sheet margin), N and P limitation (inland) and N + P co-limitation (coast). Factors including variation in N supply, ice phenology, seasonal algal succession, community structure and physical limnology are explored as mechanisms to explain differences amongst lakes. Nutrient limitation of arctic lakes and associated ecological impacts are highly variable, even across small geographic areas. In this highly sensitive region, future environmental change scenarios carry a strong risk of significantly altering nutrient limitation; in turn, potentially severely impacting lake structure and function.