Inhibition effects of some pesticides and heavy metals on carbonic anhydrase enzyme activity purified from horse mackerel (Trachurus trachurus) gill tissues

Environmental Science and Pollution Research - The gill tissue is the main site of metabolic enzymes or compensation, with the kidney tissue playing a supporting role. At the gill tissue, carbonic...     

Conservation resource allocation,small population resiliency,and the fallacy of conservation triage

Some conservation prioritization methods are based on the assumption that conservation needs overwhelm current resources and not all species can be conserved; therefore, a conservation triage scheme (i.e., when the system is overwhelmed, species should be divided into three groups based on likelihood of survival, and efforts should be focused on those species in the group with the best survival prospects and reduced or denied to those in the group with no survival prospects and to those in the group not needing special efforts for their conservation) is necessary to guide resource allocation. We argue that this decision-making strategy is not appropriate because resources are not as limited as often assumed, and it is not evident that there are species that cannot be conserved. Small population size alone, for example, does not doom a species to extinction; plants, reptiles, birds, and mammals offer examples. Although resources dedicated to conserving all threatened species are insufficient at present, the world's economic resources are vast, and greater resources could be dedicated toward species conservation. The political framework for species conservation has improved, with initiatives such as the UN Sustainable Development Goals and other international agreements, funding mechanisms such as The Global Environment Facility, and the rise of many nongovernmental organizations with nimble, rapid-response small grants programs. For a prioritization system to allow no extinctions, zero extinctions must be an explicit goal of the system. Extinction is not inevitable, and should not be acceptable. A goal of no human-induced extinctions is imperative given the irreversibility of species loss.     

Nicht reproduzierbar: Versuchsergebnisse zur synergistischen Wirkung von Xeno?strogenen

Ohne Zusammenfassung     

Ozon: Bioindikation von Photooxidantien mit Bel W3-Tabak

Results of an ozone-biomonitoring program performed from May to October 1994 at five different stations on exposed Bel W3 tobacco plants in the southwest of Germany (region of Trier) are presented. No linear dose-response relationship could be deduced between ambient ozone concentration and leaf necroses. Gas-exchange rates of tobacco plants during typical summer days would have to be determined to evaluate the stomatal uptake of photo-oxidant gases. Nevertheless, monitoring with the aid of Bel W3 tobacco plants permits an evaluation of qualitative differences in the ambient ozone concentrations. More severe leaf damage were clearly related to periods with higher radiation and was consequently found more frequently in sites located at higher altitudes. Microclimatic differences, however, may also be responsible in part for the ozone-related leaf damage seen at these sites. For this reason, only general conclusions concerning the relative levels of pollution can be deduced from biomonitoring studies using the reactivity of the indicator plant, which strongly restricts the reliability of such field studies. Pigment levels and leaf patterns in tobacco plants which still demonstrate no necrosis cannot be used as early ozone indicators.