A global perspective on wetland salinization: ecological consequences of a growing threat to freshwater wetlands
A global perspective on wetland salinization: ecological consequences of a growing threat to freshwater wetlands
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DOI：
10.1890/es14-00534.1
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发表时间：
2015-10-01
期刊：
影响因子：
2.7
通讯作者：
Gell, Peter
中科院分区：
文献类型：
--
作者：
Herbert, Ellen R.;Boon, Paul;Gell, Peter
盐碱化是对内陆和沿海湿地的结构和生态功能的一个广泛威胁，目前正在以前所未有的速度和地理规模发生。盐碱化的原因多种多样，包括改变淡水流量、土地清理、灌溉、废水处理、海平面上升、风暴潮和使用除冰盐。气候变化和人类对水文循环的改变预计将进一步增加湿地盐碱化的范围和严重程度。盐碱化改变了土壤-水环境的基本物理化学性质，增加了离子浓度，改变了化学平衡和矿物溶解度。溶质浓度的增加，特别是硫酸盐，改变了主要元素的地球化学循环，包括碳，氮，磷，硫，铁和二氧化硅。盐碱化对湿地生态地球化学的影响通常包括减少无机氮的去除（对水质和气候调节的影响），减少碳储存（对气候调节和湿地吸积的影响），增加有毒硫化物的产生（对营养循环和湿地生物群的健康/功能的影响）。事实上，盐和硫化物浓度的增加会引起湿地生物群的生理压力，最终可能导致湿地群落及其相关生态系统功能的巨大变化。淡水物种组合的生产力和组成将发生很大变化，现有种间相互作用很有可能被破坏。虽然有丰富的信息如何盐碱化影响个别生态系统的组成部分，相对较少的研究已经解决了复杂的，往往是非线性的反馈，确定生态系统规模的反应，或考虑如何湿地盐碱化将影响湿地一级的过程。虽然在许多情况下，湿地的盐碱化可能是不可避免的，这些系统也可能被证明是一个肥沃的试验场，更广泛的生态理论，包括（但不限于）：调查替代稳定状态和临界点，营养级联，干扰恢复过程，以及历史事件和景观环境中的作用，推动社会对干扰的反应。
Salinization, a widespread threat to the structure and ecological functioning of inland and coastal wetlands, is currently occurring at an unprecedented rate and geographic scale. The causes of salinization are diverse and include alterations to freshwater flows, land-clearance, irrigation, disposal of wastewater effluent, sea level rise, storm surges, and applications of de-icing salts. Climate change and anthropogenic modifications to the hydrologic cycle are expected to further increase the extent and severity of wetland salinization. Salinization alters the fundamental physicochemical nature of the soil-water environment, increasing ionic concentrations and altering chemical equilibria and mineral solubility. Increased concentrations of solutes, especially sulfate, alter the biogeochemical cycling of major elements including carbon, nitrogen, phosphorus, sulfur, iron, and silica. The effects of salinization on wetland biogeochemistry typically include decreased inorganic nitrogen removal (with implications for water quality and climate regulation), decreased carbon storage (with implications for climate regulation and wetland accretion), and increased generation of toxic sulfides (with implications for nutrient cycling and the health/functioning of wetland biota). Indeed, increased salt and sulfide concentrations induce physiological stress in wetland biota and ultimately can result in large shifts in wetland communities and their associated ecosystem functions. The productivity and composition of freshwater species assemblages will be highly altered, and there is a high potential for the disruption of existing interspecific interactions. Although there is a wealth of information on how salinization impacts individual ecosystem components, relatively few studies have addressed the complex and often non-linear feedbacks that determine ecosystem-scale responses or considered how wetland salinization will affect landscape-level processes. Although the salinization of wetlands may be unavoidable in many cases, these systems may also prove to be a fertile testing ground for broader ecological theories including (but not limited to): investigations into alternative stable states and tipping points, trophic cascades, disturbance-recovery processes, and the role of historical events and landscape context in driving community response to disturbance.