Small Boreal Lake Ecosystem Evolution under the Influence of Natural and Anthropogenic Factors: Results of Multidisciplinary Long-Term Study

Abstract

Small aquatic ecosystems of the boreal zone are known to be most sensitive indicators of on-going environmental change as well as local anthropogenic pressure, while being highly vulnerable to external impacts. Compared to rather detailed knowledge of the evolution of large and small lakes in Scandinavia and Canada, and large lakes in Eurasia, highly abundant small boreal lakes of northwest Russia have received very little attention, although they may become important centers of attraction of growing rural population in the near future. Here we present the results of a multidisciplinary, multi-annual study of a small boreal humic lake of NW Russia. A shallow (3 m) and a deep (16 m) site of this lake were regularly sampled for a range of chemical and biological parameters. Average multi-daily, summer-time values of the epilimnion (upper oxygenated) layer of the lake provided indications of possible trends in temperature, nutrients, and bacterio-plankton concentration that revealed the local pollution impact in the shallow zone and overall environmental trend in the deep sampling point of the lake. Organic phosphorus, nitrate, and lead were found to be most efficient tracers of local anthropogenic pollution, especially visible in the surface layer of the shallow site of the lake. Cycling of trace elements between the epilimnion and hypolimnion is tightly linked to dissolved organic matter speciation and size fractionation due to the dominance of organic and organo-ferric colloids. The capacity of lake self-purification depends on the ratio of primary productivity to mineralization of organic matter. This ratio remained >1 both during winter and summer periods, which suggests a high potential of lake recovery from the input of allochthonous dissolved organic matter and local anthropogenic pollution.

Reconstruction of the primary bottom of a unique crater lake in the “Meteoryt Morasko Reserve” (Poland)

“…An important fact in the broader aspect of hydrological research should also be emphasised. The paper expands knowledge on the functioning of shallow lakes, research on which according to Józsa (2014) still shows moderate level, and the issue is also noticed by other authors (Brillo 2016;Shirokova et al 2016).…”

Lake Restoration and Management in a Climate Change Perspective: An Introduction

“…Results are presented of a multi-annual study of a small boreal humic lake of NW Russia [35]. A shallow and a deep site of the lake were regularly sampled for a range of chemical and biological parameters.…”

Quantification of Hydrological Responses Due to Climate Change and Human Activities over Various Time Scales in South Korea

“…An understanding of the relative impacts of climate change and human activities on hydrological responses should be integral to the creation of a water management plan [20]. The quantitative separation of the impacts of climate change and human activities has therefore drawn attention [21][22][23][24][25][26][27][28][29]. Particularly in South Korea, more attention has been paid to the identification of impacts from the two types of factors because of strong variation in regional precipitation and rapid urban development during the past few decades.…”