Do Nitrogen Concentration and Forage Quality of the MossRacomitrium lanuginosumIncrease with Latitude?

Mosses are an important component of high latitude ecosystems, contributing the majority of the plant biomass in many communities. In Arctic regions mosses also form a substantial part of the diet of many herbivore species. This may reflect either the availability of moss or its quality as forage. Here we test whether the nitrogen concentration and forage quality of the mossRacomitrium lanuginosumincrease with latitude and discuss the findings with reference to herbivore utilisation of moss in the Arctic. In contrast to vascular plants, moss nitrogen concentration significantly decreased with latitude (P<.01), in line with estimates of N deposition at the sampling sites. In addition, no evidence of an increase in nutritional quality of moss with latitude was observed; thus, this study suggests that the utilisation of moss by herbivores in arctic ecosystems maybe a function of their relatively high biomass rather than their quality as forage.

Effect of Low pH on Carbohydrate Production by a Marine Planktonic Diatom (Chaetoceros muelleri)

Rising carbon dioxide (CO2) concentrations in the atmosphere due to human activity are causing the surface ocean to become more acidic. Diatoms play a pivotal role in biogeochemical cycling and ecosystem function in the ocean. pH affected the quantum efficiency of photosystem II and carbohydrate metabolism in a planktonic diatom (Chaetoceros muelleri), representative of a widely distributed genus. In batch cultures grown at low pH, the proportion of total carbohydrate stored within the cells decreased and more dissolved carbohydrates were exuded from the cells into the surrounding medium. Changes in productivity and the way in which diatoms allocate carbon into carbohydrates may affect ecosystem function and the efficiency of the biological carbon pump in a low pH ocean.

Seychelles Lagoon Provides Corals with a Refuge from Bleaching

An extensive bleaching event in the summer of the year 1997-1998 affected most reefs along East Africa's shores. In the aftermath of that episode, the reefs of Île Alphonse in the Seychelles were examined and it was found that reefs along the seaward slopes of the island lost >95% of their branching coral colonies, with considerably higher survival of massive species. Île Alphonse features a nearly circular shallow lagoon, with steep seaward slopes. Contrary to our expectations, mortality in the warmer lagoon was far lower than of coral colonies on the surrounding slopes, bathed in deeper and cooler waters. We suggest that corals in the lagoon were protected from UV radiation by leachate stemming from seagrass leaves steeped in the lagoon. Our measurements in the lagoon showed a strong attenuation of ultraviolet radiation, not observed in the waters outside the lagoon, and laboratory examination confirmed that the strong UV absorption of substances leached into seawater from decomposing leaves of the seagrassThalassodendron (=Cymodocea) testudinaceum. Our findings demonstrate the synergism between elevated seawater temperature and UV radiation in triggering bleaching on shallow reefs.

Shared Reproductive State Enhances Female Associations in Dolphins

Female bottlenose dolphins (genusTursiops) usually associate at moderate level with other females within social clusters called bands or cliques. It has been suggested that reproductive state may play the predominant role in determining associations within femaleT. truncatusbands. Here, we test the hypothesis that reproductive state correlates with associations of female Indo-Pacific bottlenose dolphins (T. aduncus). We found that females in similar reproductive state, which included females from late pregnancy to the first year of their calves' life or females from early pregnancy to their calves' newborn period, had higher-association coefficients with each other than they did with females in different reproductive states (females with older calves or without calves). This was observed both within and across social clusters suggesting that reproductive state, at least for pregnant females and those with young calves, plays an important role in determining who to associate with. However, a female's most frequent associate was not always with another in similar reproductive state. We suggest that several factors, including reproductive state, may be of importance in determining associations of female bottlenose dolphins.

On Some New Indicators for the Energo-Ecological Assessment of Thermo-Power Plants Operation

The authors offer a critical analysis of pollution indicators currently applied for the ecological assessment of the thermo power plant's operation. They forward new “energo-ecological” indicators to highlight both the qualitative aspect of polluting emissions and their quantitative aspect, by relating their concentration in the flue gases purged into the atmosphere to the energy produced during the same interval. The application of these indicators contributes to the attenuation of the global warming phenomenon and to the protection of the world's resources of fossil fuels.

“Brown” World Invertebrates Contradict “Green” World Biodiversity Theory

Biodiversity-productivity theory predicts that ecosystems with increased productivity due to excessive limiting-nutrient loading will have decreased taxonomic diversity. In this 4-year study, we elevated productivity by adding NPK fertilizer to 20 m diameter plots in an old-field grassland to test the effects of anthropogenically mediated nutrient loading on plant and epigeal arthropod communities. While plants responded as predicted by the biodiversity-productivity theory, the epigeal arthropod community had highest species richness within the fertilized high-productivity treatments. We conclude that the contradictory response of the largely detrital-based epigeal community should alter conventional biodiversity-productivity theory and could affect terrestrial biodiversity conservation strategies.

Chlorophyll Detection and Mapping of Shallow Water Impoundments Using Image Spectrometry

There exists a common perception that chlorophyll a concentrations in tidal coastal waters are unsuitable to be captured by remote sensing techniques because of high water turbidity. In this study, we use band index measurements to separate active chlorophyll pigments from other constituents in the water. Published single- and multiband spectral indices are used to establish a relationship between algal chlorophyll concentration and reflectance data. We find an index which is suitable to map chlorophyll gradients in the impoundments, ditches, and associated waterways of the Hackensack Meadowlands (NJ, USA). The resulting images clearly depict the spatial distribution of plant pigments and their relationship with the biological conditions of the waters in the estuary. Since these biological conditions are often determined by land usage, the methods in this paper provide a simple tool to address water quality management issues in fragmented urban estuaries.

The DiatomAnorthoneis dulcisHein from Southern Brazil: Morphology and Ecology

A new geographic locality forAnorthoneis dulcisis reported. The paper describes the distribution and relative abundance ofA. dulcisin Lagoa dos Patos lagoon (a lagoon in Rio Grande do Sul state, Brazil) from samples collected between 2004 and 2005, and shows that this rare species is present all year round. This study extends the species distribution to South America indicating that the species can thrive on sand grains in lentic estuarine, and freshwater areas. It widens the range of tolerance to environmental parameters. The valve fine structure, morphology, and dimensions are in agreement with the original diagnosis.

Increased Chlorophyll Levels in the Southern Caspian Sea Following an Invasion of Jellyfish

A significant correlation was observed between satellite derived chlorophylla(Chla) concentrations and the biomass of the invasive comb jellyfishMnemiopsis leidyiin the southern Caspian Sea. By consuming the herbivorous zooplankton, the predatory ctenophoreM. leidyimay have caused levels of Chlato rise to very high values ( mg ) in the southern Caspian Sea. There might also be several other factors concurrent with predation effects ofM. leidyiinfluencing Chlalevels in this region, such as eutrophication and climatic changes which play major roles in nutrient, phytoplankton, and zooplankton variations. The decrease in pelagic fishes due to overfishing, natural, and anthropogenic impacts might have provided a suitable environment forM. leidyito spread throughout this enclosed basin.

Corporate Ecological Footprint: New Conversion Factors

The first ecological footprint calculation version, applied to companies, appeared in 2003. The said tool provides the possibility of calculating the total impact of a company or organisation in hectares or in equivalent emissions of . This paper updates carbon absorption rates and improves electricity consumption conversion factors, one of the major footprint generating consumptions in companies. The new rates prove that the footprint estimated to date will be notably increased as, among other aspects, the IPCC has downgraded the amount of carbon that forests are capable of absorbing. These data reveal that companies must make a great effort to adapt to the challenges triggered by climate change.