Good Environmental Indicators Research Articles

Bioaccumulation of heavy metals in Liza saliens from the Esmoriz–Paramos coastal lagoon, Portugal

Heavy metal (Cu and Zn) concentrations in liver, gills, and muscle of leaping grey mullet, Liza saliens, from the Portuguese Esmoriz–Paramos coastal lagoon were measured to evaluate their bioaccumulation as a function of sediment contamination. The highest metal concentrations were observed in the liver (254 mg Cu kg −1) and gills (114 mg Zn kg −1). Bioaccumulation factors (BAFs) were found to follow the order: Cu-liver>Cu-gills>Cu-muscle and Zn-gills>Zn-liver>Zn-muscle. The highest BAFs were observed in the organs mainly implicated in metal metabolism and a significant positive relationship was found between BAFs and fish age. These results suggest the loss of homeostatic capacity of L. saliens under chronic metal exposure leading to bioaccumulation. Furthermore, Cu-liver and Zn-gills accumulation can be good environmental indicators of metal stress in L. saliens.

A description of the developmental stages ofAcylophorus wagenschieberi Kiesenwetter, 1850 (Coleoptera, Staphylinidae), with comments on its biology, egg parasite and distribution in Polandy

The egg, three larval instars and pupa of Acylophorus wagenschieberi Kiesenwetter are described for the first time, with the illustrations of structural features provided. Adult habitus and figures for penis are given. Differences in the morphological structure of its larval instars (L1—3) cover: the number and structure of setae on protibia, the number of setae on tarsungulus, the number of setae on pygopod, the structure of urogomphi, the body color and the measurements of size. Diagnostic characters of immature stages are listed. Modifications of the keys to known eggs, larvae and pupae of the European Staphylininae species are proposed. Some data on its distribution, environmental requirements and biology with the schema of life cycle in the field are also provided. It is stenotopic and one of the rarest-occurring Staphylininae species in its whole distribution range, in Poland known from 13 localities (11 recorded by the author). It occurs exclusively on high- and transitional moors, preferring the ecotone zones between water bodies and the surrounding peatbogs. One of the main factors limiting its occurrences and abundance is the high and stable water level. A. wagenschieberi is a monovoltine species with the summer larvae and wintering imago. Considering its environmental preferences and biology this rove beetle may be of essential importance as a good environmental state indicator. Trimorus fulvimanus Kiefer (Scelionidae, Proctotrupoidea, Hymenoptera) has been recorded as an egg parasite of A. wagenschieberi. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Dragonfly (Odonata) distribution patterns in urban and forest landscapes, and recommendations for riparian management

Odonata species are particularly sensitive to human disturbances. Their diversity relative to four landscape types (plantation forest, parkland, residential area, industrial area) along a small river (the Dorpspruit) that runs through Pietermaritzburg, South Africa, is described. Individual species-environment relations were investigated using the multivariate analysis package CANOCO. Four biotope types were identified and characterised. The analysis also illustrated the extent to which the urban, suburban and forestry environments affected the Odonata species. Multispecies assemblages were good environmental indicators. Individual indicator species included Chlorolestes tessellatus and Crocothemis erythraea. Chlorolestes tessellatus is a good indicator of the minimal width (> 30 m) of the indigenous strip of riparian vegetation between the stream edge and commercial plantations. This study suggests that there should be a riparian strip between the water's edge and plantation trees of at least 20 m (preferably 30 m). This finding is integrated with earlier ones to arrive at a general conservation management recommendation, at least for dragonflies, for rivers in South Africa.

Lead and cadmium in meat and organs of game in Slovenia

Pollution of the environment and contamination of animals including game with Pb and Cd are serious problems in most countries. Our many-years results of Pb and Cd residues in meat and organs of game show us, that the herbaceous game, which feed only with various herbs are more contaminated than other animals - cattle and pigs. They really seem to be a good environmental contamination indicator. The aim of our research was to establish contamination levels of game with Pb and Cd. Two different regions of Slovenia, an industrial region with a lead mine and smeltry in Koroska and an unindustrial one a Ilirska Bistrica were chosen to study contamination of game. Muscle tissues, heart muscles, kidneys and livers of roe-deer, chamois, red-deer and wild boards were analysed. The correlation between the animals` age and cadmium content in kidney was researched and a positive correlation was established. We have found out to which extent the meat and organs of game correspond with our available tolerances for each single residue and whether they are unfit for human consumption. The results of investigations concerning Pb and Cd content in game analysed in Slovenia in the last four years were shown, too. Resultsmore » were taken from the reports of the Residue monitoring and surveillance which is performed in the Republic Slovenia for more than ten years. 6 refs., 5 tabs.« less

Assessing the Indicator Properties of Species Assemblages for Natural Areas Monitoring.

The diversity of organisms and complexity of ecosystems prevent through inventory and monitoring of protected areas, yet sound databases are needed to manage ecosystems for long-term persistence. One strategy is therefore to focus monitoring on indicator organisms, but guidelines are lacking for selecting appropriate species or groups. This paper presents a simple protocol based on ordination techniques for establishing the indicator properties of a group of organisms and for selecting an indicator species subset for more intensive monitoring. Use of ordination allows inclusion of many more taxa than have been traditionally used for natural areas monitoring, and need not rely on detailed knowledge of species biology. As an example, I studied the indicator properties of a butterfly taxocene in a rain forest in Madagascar. Butterflies have been suggested as particularly good environmental indicators due to their sensitivity to micro-climate and light level changes, and their interactions as larvae and adults with different sets of host plants. The indicator properties of butterfly assemblages were evaluated in this study with respect to a known pattern of environmental heterogeneity along topographic/moisture and disturbance gradients. Butterfly assemblages were found to be excellent indicators of heterogeneity due to the topographic/moisture gradient, limited indicators of heterogeneity due to anthropogenic disturbance, and poor indicators of plant diversity. The protocol defined in this study is widely applicable to other groups of organisms, spatial scales, and environmental gradients. By examining the environmental correlates of the distribution of species assemblages, this protocol can assess the indicator properties of target species groups.

Effect of watertable on yield and root depth of winter wheat in the French West Central Atlantic Marshlands

The watertable in winter depends on the field drainage system and the structural stability of the soils. The yield of winter wheat and the nitrogen supply of the soil are positively correlated with a lower water-table. Therefore, the mean watertable in winter is a good environmental indicator for the yield potentialities For the explanation of yield variations, the depth of the root system was observed at the start of stem elongation and the anthesis. At the start of stem elongation, the root depth (E i) increases with a lower watertable in winter (r = 0.931). The root depth after anthesis (E f) depends on the root depth at stem elongation (E i) and on the climatic balance R (rainfall)-ET (evapotranspiration) between these two stages. For R>ET, R = ET and R<ET, root growth (dE = E f−E i) is respectively almost zero, decreases with increasing E i (“growth of roots making up for lost time”) or increases with increasing E i (“homothetic growth”). The root depth studies explain the relation between the pedoclimatic and environmental conditions and the yield of winter wheat.