| From traditional biomonitoring to continuous ecological biomonitoring of the near future |
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GUDIMOV A.V. Biomonitoring is currently the main instrument for evaluating the effect of environmental changes on biological systems.Its purpose is supposed to evaluate results of anthropogenic impact on all biological components of marine ecosystems (plankton, benthos, and fish) in their natural combination. Benthos is the major object of biomonitoring. Inevitable growth of anthropogenic load on marine ecosystems during exploration, development and operation of hydrocarbon deposits on the shelf led to increase of biomonitoring role in the control of environmental safety in the sea; what is of current importance for vulnerable ecosystems of the arctic seas. Physico-chemical monitoring is not able to determine an actual effect and the danger scope of any influence on biosystems because of biological responses ambiguity, the synergism and complexity of natural effects. Bioassays conducted in simulated experimental conditions are important but they establish only approximate, rough evaluation of toxicity or hazardous substance impact. The results obtained in conditions of natural dynamics of environmental factors revealed that in nature an organism response to the current changes (increase or decrease) of any factor does not correspond to estimated effects, based on the results of laboratory experiments. As a rule, the sensitivity of an organism measured in natural conditions is higher and it can considerably vary in time (Gudimov, 2006). The question is: Is the use of traditional ecological biomonitoring able to catch still hardly noticeable changes of biological communities during (at the first stage) anthropogenic pollution? Does the biomonitoring protect an ecosystem from anthropogenic changes and degradations? Actually it does not, because it works with a long delay. The problem is that there are some shortcomings, which are objectively characteristic of the standard biomonitoring - inertia and low sensitivity to environmental changes are two of them. Quality of monitoring directly depends on correct choice and observance of major approaches. First of all, natural long-termed population and community change must be taken into account. The anthropogenic changes can be traced only against a background of long-termed, seasonal and spatial dynamics of ecosystem components. The valid biomonitoring is laborious, long-termed activity requiring full-time work of experts. Otherwise, the results of monitoring are good to make hypotheses and suppositions, not forecast. In practice only drastic and stable environmental changes for a few years can be caught by the ordinary biomonitoring methods. Even observing the major approaches and despite the complexity, significant efforts and high cost of monitoring investigations, still exists a risk to take natural biota variability for the changes caused by contamination, especially, as regards to dynamic conditions of the coastal zones. Biological consequences of chronic, low intense as well as short-term heavy contamination are hardly detected with the standard biomonitoring. Technological inertia of the biomonitoring is inevitably doubled even in spite of the application of the common bioindication systems, it is because the biomonitoring is “turned to the past” system, i.e. the observed population and biocenoses state reflects none the current but the bygone environmental changes. Bottom community structure is not resulted from the conditions of this year, but from ones of 6-7 years’ remoteness (Frolova et al., 2007) and partly from environmental changes of the last several years. In practice only long-term (from 5 to 10 years) or catastrophic changes in communities are surely detectable by the methods of traditional biomonitoring and bioindication. Less significant changes in biocenoses, as well as anthropogenic effects of a smaller scale and organism responses to the routine though important environmental changes, are in fact ignored, because the old methods of traditional biomonitoring fail to detect these events. Meanwhile short-term effects can result in expansion (progress) of destructive and crisis phenomena in the ecosystem, which can lead to reducing of the biodiversity and marine biological resources. Therefore, the main disadvantage of standard ecological biomonitoring is that it determines anthropogenic effects post factum with considerable gap from the moment of its emerge i.e. when possibly significant and irreversible changes in biological communities (benthos) took place. It is. A major current direction for development of biomonitoring is the use of bioindicators of various biosystem levels (from organism to community). However, the worldwide approaches to biomonitoring/bioindication practice conceptually and methodically remain the same, along characteristic disadvantages of traditional monitoring: considerable inertia and very low responsiveness. The problem is the development of water biomonitoring technology which can meet the up-to-date technological development and ensure the level of ecological safety which surpasses significantly the existing traditional biomonitoring in all capabilities. Such technology should be universal and primarily operational, i.e. should be able to detect a biosystem response at any time domain. Technology of the continuous biomonitoring developed in MMBI (Matishov, et al. 2008) may realize the permanent biological on-line control of environmental conditions based on methodology of multilevel bioindication.
The concept of multilevel bioindication is based on the notion that the rates of biological processes in ecosystem differ at different levels of biological organization (from organism to community). Hence, at the organism level, the response rate and sensitivity to external factors, i.e. responsiveness, are much higher than those at the population and biocenosis levels. Different rates of the processes determine distinctions in discreteness of measuring (scales) and the methods used. This concept suggests a fundamentally new approach to monitoring. The multilevel system of biological indicators is primarily a temporal hierarchy of measurements in situ, rather than the standard set of indicator parameters at various biosystem levels taken with snap samples (e.g., during a benthos survey). Biomonitoring based on the system of multilevel bioindication possesses the minimal discreteness, i.e. it is continuous/on-line and it allows us to estimate response of different level biosystems in any scale and time range of environmental conditions changes. References |