Bagasse-assisted bioremediation of ammonia from shrimp farm wastewater.

Development of new economically feasible ecofriendly products from agricultural wastes or byproducts for shrimp farm wastewater treatment is the objective of our continued research. Ammonia is a nitrogenous toxicant, which is commonly found in wastewater from shrimp farms. In the present study, we explored the possibility of the use of simply and inexpensively prepared bagasse products so that this abundant crop byproduct could be used to remove ammonia from shrimp farm wastewater. Bagasse, a natural highly fibrous lignocellulosic byproduct of sugarcane, was converted into five different products. Experimental results have shown that ammonia is efficiently removed from wastewater by four bagasse products with a dose of 1 to 6 g/L within 24 hours. The effect of bagasse products on other water quality parameters and growth kinetics of biofilm bacteria onto bagasse fiber have also been studied. Efficacies of products were compared by using statistical analysis. Products developed from bagasse are useful and economical.     

Correlated northward distribution of macrolepidopterans and their food plants along the Ural Mountains

Lists of macrolepidopterans inhabiting the Southern, Middle, and Polar Urals have been used for analyzing the relationship between the species richness of these insects with that of the families of plants on which their larvae feed. The results have shown that this factor in the Southern Urals accounts for approximately 75% and 65% of variation in the species richness of lepidopterans on woody and herbaceous plants, respectively. In the Polar Urals, this correlation is markedly weaker. Latitudinal trends in trophic preferences of individual lepidopteran taxa have been revealed. Probable causes of changes in the relative abundance of lepidopterans north of the forest zone are discussed.     

Composting of vegetable waste.

The effects of the aeration, seeding, and agitation on the composting of vegetable waste were studied in a laboratory-scale reactor. Experimental results showed that the final product at the end of a 4-day composting period met multiple maturity indices suggested by many researchers. The evolution of carbon dioxide during the composting process could be modelled with a modified Gompertz equation that described the bacteria growth successfully. Multivariate regression analysis was used to study the effects of operating parameters on the carbon conversion. The response surface contour plots were constructed using the regression equation for the examination of the dependence of carbon conversion on operating parameters. The maximum carbon conversion of 14.54% was obtained when the percentage of seeding was set at 14.5%, the air suction rate was set at 2.6 L kg(-1) dry-solid min(-1), and the agitator operated half of the time, alternating on and off for every 5 min. Future work will focus on the application of the data and the experience gained in this work to composters of pilot and semi-commercial scales.     

Differences in Evaporation Between a Floating Pan and Class A Pan on Land1

Abstract: Research was conducted to develop a method for obtaining floating pan evaporation rates in a small (less than 10,000 m²) wetland, lagoon, or pond. Floating pan and land pan evaporation data were collected from March 1 to August 31, 2005, at a small natural wetland located in the alluvium of the Canadian River near Norman, Oklahoma, at the U.S. Geological Survey Norman Landfill Toxic Substances Hydrology Research Site. Floating pan evaporation rates were compared with evaporation rates from a nearby standard Class A evaporation pan on land. Floating pan evaporation rates were significantly less than land pan evaporation rates for the entire period and on a monthly basis. Results indicated that the use of a floating evaporation pan in a small free‐water surface better simulates actual physical conditions on the water surface that control evaporation. Floating pan to land pan ratios were 0.82 for March, 0.87 for April, 0.85 for May, 0.85 for June, 0.79 for July, and 0.69 for August.     

Are shrubland birds edge specialists?

In studies of forest fragmentation, birds of scrubby, early-successional habitats are considered edge specialists. Because these birds are assumed to thrive in fragmented, edge-dominated areas, their landscape ecology has received little attention from ecologists. With populations of shrubland birds declining throughout the eastern United States, the question of whether or not these birds really prefer edge habitats has important conservation implications. We used a meta-analysis to test how edges affect the abundance of shrubland birds in early-successional habitats. We analyzed data for 17 species from seven studies that compared the abundances of birds in the interiors and edges of regenerating clearcuts surrounded by mature forest. The meta-analysis clearly showed that shrubland birds avoid edges. All 17 species tested had higher abundances in patch centers than along edges, and edge effects were significant for 8 of 17 species. The key implication of this result is that small or irregular patches, dominated by edge, are unlikely to provide suitable habitat for shrubland birds. Thus, management for these declining species should involve providing large patches and minimizing edges. These findings demonstrate the importance of testing widely accepted ecological classifications and the need to view landscape ecology from the perspective of non-forest wildlife.     

Lands for Long-Term Research in Conservation Biology

Abstract: Success in conservation biology depends upon a synergistic combination of short-term tactics and long-term strategies. Although the former are often necessary to forestall immediate habitat losses, the latter provide the critical framework of understanding needed to develop effective short-term priorities. Although many conservation biologists now emphasize short-term tactics, prudence dictates the concomitant establishment of long-term research projects aimed at answering fundamental ecological questions.
One deterrent to amassing such long-term data bases, aside from time and funding, is a lack of suitable sites where such studies can be conducted on a large scale. We describe two established major land-holding networks in the United States that could serve as appropriate places to develop long-term studies: the National Science Foundation's Long-Term Ecological Research (LTER) sites, and the US. Department of Energy's National Environmental Research Parks (NERPs). Because they consist of established research facilities, both networks can provide conservation biologists with "low-cost" baseline information on ecological processes, as well as access to a number of representative terrestrial and aquatic habitats under more or less "controlled" conditions suitable for long-term studies. We recommend that conservation biologists explore the possibility of using these or similarly available sites in their research programs.     

Conspecific flowers of <Emphasis Type="Italic">Sinapis arvensis</Emphasis> are stronger competitors for pollinators than those of the invasive weed <Emphasis Type="Italic">Bunias orientalis</Emphasis>

Biological invasions can affect the structure and function of ecosystems and threaten native plant species. Since most weeds rely on mutualistic relationships in their new environment, they may act as new competitors for pollinators. Pollinator competition is likely to be density dependent, but it is often difficult to disentangle competition caused by flower quality from effects caused by flower quantity. In order to test the effects of the presence and number of flowers of the invasive weed Bunias orientalis on the insect visitation rates in a native species (Sinapis arvensis), we performed two replacement experiments using plants with standardised flower numbers. The visitation rates in S. arvensis were significantly higher than in B. orientalis and the number of insect visits dropped significantly with increasing density of S. arvensis flowers. These results suggest that intraspecific competition among flowers of S. arvensis is stronger than the competitive effect of alien flowers. As flowers of B. orientalis do not seem to distract visitors from S. arvensis, it is unlikely that pollinator competition between these two plant species plays a crucial role. However, it cannot be excluded that mass blossom stands of B. orientalis may distract flower visitors from native species.     

Geographic variation in resource allocation to the abdomen in geometrid moths

A resource allocation trade-off is expected when resources from a common pool are allocated to two or more traits. In holometabolous insects, resource allocation to different functions during metamorphosis relies completely on larval-derived resources. At adult eclosion, resource allocation to the abdomen at the expense of other body parts can be seen as a rough estimate of resource allocation to reproduction. Theory suggests geographic variation in resource allocation to the abdomen, but there are currently no empirical data on it. We measured resource allocation to the abdomen at adult eclosion in four geometrid moths along a latitudinal gradient. Resource (total dry material, carbon, nitrogen) allocation to the abdomen showed positive allometry with body size. We found geographic variation in resource allocation to the abdomen in each species, and this variation was independent of allometry in three species. Geographic variation in resource allocation to the abdomen was complex. Resource allocation to the abdomen was relatively high in partially bivoltine populations in two species, which fits theoretical predictions, but the overall support for theory is weak. This study indicates that the geographic variation in resource allocation to the abdomen is not an allometric consequence of geographic variation in resource acquisition (i.e., body size). Thus, there is a component of resource allocation that can evolve independently of resource acquisition. Our results also suggest that there may be intraspecific variation in the degree of capital versus income breeding.