Acetylcholinesterase and ethoxyresorufin-o-deethylase in the surgeonfish Acanthurus bahianus around Martinique Island (French West Indies)

Abstract

The biochemical indicators of biological effects of pollutants, ethoxyresorufin-edeethylase (EROD) and acetylcholinesterase (AChE), were measured in Acanthurus bahianus from 10 stations around Martinique Island (French West Indies). Strong induction of EROD was demonstrated in the bay of Fort de France in relation to organic pollution. Depression of AChE may suggest that neurotoxic compounds are having some effects along the east coast.     

Impact of a diamond mining industry on metabolites in Larix gmelinii

We studied the technogenic impact of a diamond mining company on the content of metabolites in the needles of Larix gmelinii (Rupr.) Kuzen. The samples of larch needles were collected in the Arctic zone in the restricted area where the diamond mining company works. The studied sites are located in Anabarsky district of Yakutia (Russia). An activity of the diamond mining company did not have a significant impact on the characteristics of the forest stand. But at the same time, near the sorting and enriching plants of the diamond mining company, the concentrations of Si, Ca, Fe, Mn, Al, Na, Sr, Ba, Zn, Pb, Ni, V were higher in the needles of L. gmelinii than those in the control zone. The activity of the diamond mining industry resulted in: intensification of the lipid peroxidation process, growth of a content of resin acids and amino acids, activation of cellular respiration processes, thickening of the cell wall, and a decline in the concentration of unsaturated fatty acids and antioxidants. We have concluded that some observable biochemical changes occur in the trees as a resulting effect of adaptive processes to the technogenic load despite the absence of significant changes in the forest stand.     

Stability and change of phytoplankton communities in a highly dynamic environment—the case of large,shallow Lake Balaton (Hungary)

Time series data of key environmental variables (water temperature, global radiation, vertical light attenuation, internal P load) and biomass of four colour classes of photosynthetically active algae were collected during 2003 and 2004 with daily resolution. Using these data, seasonal patterns of phytoplankton were analyzed as a function of the dynamic environment. Abstraction of the environmental state as a point in multi-dimensional space was used to identify habitat templates of bloom-forming groups and derive an indicator of environmental stability/physical disturbance. These templates were synthesized into a simple threshold model that sufficiently simulated development and collapse of various blooms. Blooms were, however, rare events related to specific environments with strong, unidirectional forcing. Tentative quantification of disturbance and compositional stability/community change allowed discriminating disturbance-driven changes and autogenic succession with reasonable success. The two processes were found to be equally important in shaping the composition and biomass of phytoplankton.     

Short term biotic response before and during the treatment of an acid mine drainage with sodium carbonate

The lower portion of Upper Three Runs, a woodland stream in central Pennsylvania, receives acid drainage from a strip mine. In 1974, the effect of this input on pH and benthic invertebrates was studied by Tomkiewicz & Dunson (1977). We sampled the same stations in 1986 and then treated the mine drainage with sodium carbonate for seven days in an effort to evaluate the short term colonization response of brook trout (Salvelinus fontinalis) and invertebrates. No differences in the pattern of pH and invertebrate distribution was found between the 1974 and 1986 results, although pH values and invertebrate densities were higher in 1986. Total number of invertebrates and number of taxa colonizing bricks during three pre-treatment time periods (8, 10, 18 days) did not differ from the single treatment period (7 days). However, two species of Baetis (Ephemeroptera: Baetidae) did increase in the treatment section during sodium carbonate application. The number of brook trout also increased in the treatment section, as compared to one pre-treatment estimate. These results indicate that motile species are able to respond within seven days, whereas, longer treatment may be required to produce community wide responses.Author to whom correspondence should be addressed     

Ordination analysis and bioindices based on zoobenthos communities used to assess pollution of a lake in southern Finland

The suitability of an ordination method, detrended correspondence analysis (DCA), was tested in assessing the degree of pollution of a large lake on the basis of the zoobenthos communities. Lake Etelä-Saimaa, in southern Finland, was originally oligotrophic but is now heavily loaded by effluents from the wood-processing industry. Comparison between areas was complicated by variation in the water depths of the lake sub-basins. A horizontal pollution gradient could, however, easily be detected by means of the DCA in both the profundal and sublittoral zones. The benthic quality index (BQI) based on the composition of the profundal chironomid fauna failed at some stations because the indicator species were lacking, despite enlargement of the indicator species pool. The BQI based on the oligochaetes could be calculated at almost all the stations. This index was modified by altering the empirical constants for two species. Diversity indices and the occurrences of single species had a limited value in the water quality assessment. The study concluded that DCA ordination is a powerful tool in evaluation of pollution. The method gives the best results when the sampling network is carefully planned and the material represents all sections of the underlying environmental gradients, e. g. a gradient from oligotrophy to eutrophy or heavy pollution.     

Industrial melanism and peppered moths (Biston betularia (L.))

The spread of melanic forms of the peppered moth ( Biston betularia (L.)) over polluted areas of Britain from the mid-nineteenth century onwards, has become widely known and quoted as a classical example of microevolutionary change. Probably the most important factor in the spread (and subsequent decline, following the Clean Air Act) of the melanics has been bird predation on less cryptic individuals, but a range of other factors may also affect the maintenance of allele frequencies at any one place (site selection, dispersion, heterosis, frequency dependent selection, larval hardiness, etc). The development of the "Peppered Moth Story" is described, and suggestions made about needed research.     

Variation in foliar δ13C in Hawaiian Metrosideros polymorpha: a case of internal resistance?

Summary Sun leaves of Metrosideros polymorpha were collected in 51 sites on 9 lava flows that represented gradients of elevation, precipitation, substrate age, and substrate texture on Mauna Loa volcano, Hawai'i. Leaf mass per unit leaf area increased with increasing elevation on all flows, while foliar nitrogen concentration decreased with increasing elevation and increased with increasing substrate age. Foliar ¹³C became less negative with increasing elevation on the wet east-side lava flows, but not the dry northwest-side flows; it did not reflect patterns of precipitation or presumed water availability. ¹³C was very strongly correlated with leaf mass per area across all of the sites. Limited gas-exchange information suggested that calculated c_i/c_a did not decrease with elevation in association with less-negative ¹³C, and photosynthesis per unit of nitrogen was significantly reduced in high-elevation plants. These results are consistent with a substantial internal resistance to CO₂ diffusion in the thick Metrosideros polymorpha leaves in high elevation sites.Published as a contribution to the International Union for Biological Sciences Tropical Mountain Ecosystems Program, and as Carnegie Institution of Washington Department of Plant Biology Publication Number 1065     

Stimulation of ethylene production and gas-space (aerenchyma) formation in adventitious roots of Zea mays L. by small partial pressures of oxygen

Adventitious roots of two to four-weekold intact plants of Zea mays L. (cv. LG11) were shorter but less dense after extending into stagnant, non-aerated nutrient solution than into solution continuously aerated with air. Dissolved oxygen in the non-aerated solutions decreased from 21 kPa to 3–9 kPa within 24 h. When oxygen partial pressures similar to those found in non-aerated solutions (3, 5 and 12 kPa) were applied for 7 d to root systems growing in vigorously bubbled solutions, the volume of gas-space in the cortex (aerenchyma) was increased several fold. This stimulation of aerenchyma was associated with faster ethylene production by 45-mm-long apical root segments. When ethylene production by roots exposed to 5 kPa oxygen was inhibited by aminoethoxyvinylglycine (AVG) dissolved in the nutrient solution, aerenchyma formation was also retarded. The effect of AVG was reversible by concomitant applications of 1-aminocyclopropane-1-carboxylic acid, an immediate precursor of ethylene. Addition of silver nitrate, an inhibitor of ethylene action, to the nutrient solution also prevented the development of aerenchyma in roots given 5 kPa oxygen. Treating roots with only 1 kPa oxygen stimulated ethylene production but failed to promote gas-space formation. These severely oxygen-deficient roots seemed insensitive to the ethylene produced since a supplement of exogeneous ethylene that promoted aerenchyma development in nutrient solution aerated with air (21 kPa oxygen) failed to do so in nutrient solution supplied with 1 kPa oxygen. Both ethylene production and aerenchyma formation were almost completely halted when roots were exposed to nutrient solutions devoid of oxygen. Thus both processes require oxygen and are stimulated by oxygen-deficient surroundings in the 3-to 12-kPa range of oxygen partial pressures when compared with rates observed in air (21 kPa oxygen).Abbreviations ACC 1-aminocyclopropane-1-carboxylic acid - AVG aminoethoxyvinylglycine     

锌污染对植物的毒害及植物的忍耐性

锌在土壤中的总含量一般为10—300ppm,个别土壤可达500—1000ppm;在一些铅、锌矿区土壤的含锌量可高达2800ppm,甚至更高。锌是植物生长发育的必需元素,但环境中过量的锌会造成环境污染,使一些植物受害不能生存,一些植物可