Screening and identification of early warning algal species for metal contamination in fresh water bodies polluted from point and non-point sources

The water bodies of Lucknow, Unnao and Kanpur (U.P.), India polluted through various point and non point sources were found to be either eutrophic or oligotrophic in nature. These water bodies supported a great number of algal diversity, which varied seasonally depending upon the physico-chemical properties of water. Further, the water bodies polluted through non point sources supports diverse algal species, while the water bodies polluted through point sources supports growth of tolerant blue green algae. High biomass producing algal species growing in these water bodies have accumulated significant amount of metals in their tissues. Maximum amount of Fe was found accumulated by species of Oedogonium sp. II (20,523.00 mug g(-1) dw) and Spirogyra sp. I (4,520.00 mug g(-1) dw), while maximum Chromium (Cr) was found accumulated in Phormedium bohneri (2,109.00 mug g(-1) dw) followed by Oscillatoria nigra (1,957.88 mug g(-1) dw) and Oedogonium sp. I (156.00 mug g(-1) dw) and Ni in Ulothrix sp. (495.00 mug g(-1) dw). Results showed that some of these forms growing in polluted environment and accumulating high amounts of toxic metals may be used as bioindicator species, however, their performance in metal contaminated water under different ecological niche is to be ascertained.     

Characteristics of atmospheric carbonyls and VOCs in Forest Park in South China

The diurnal variation of atmospheric carbonyls and VOCs in a forest in south China were studied in summer 2004. Twenty kinds of carbonyls and eight kinds of VOCs were identified and quantified. Formaldehyde and acetaldehyde were the two most abundant carbonyls, while the most abundant VOCs were isoprene, followed by o-xylene. Most C₃-C₁₀ carbonyls had higher concentrations from 09:00 to 15:00, and their levels were lower during night-time and often reached the lowest in early morning. Formaldehyde and acetaldehyde, however, showed two high levels in their diurnal patterns partly due to their different sources and sinks. The VOCs had different diurnal patterns compared to most carbonyls. The highest concentrations were observed from 03:00 to 06:00 for 1-butene, from 06:00 to 12:00 for isoprene, and from 12:00 to 15:00 for α-pinene. The highest levels for aromatic hydrocarbons occurred during midnight and the lowest in late afternoon. According to the study, emissions from vegetation and photo-oxidation of gas-phase hydrocarbons were the main sources for some carbonyls and VOCs in this region. Other compounds, such as formaldehyde, acetaldehyde and BTEX, showed anthropogenic sources.     

Coupling upland watershed and downstream waterbody hydrodynamic and water quality models (SWAT and CE-QUAL-W2) for better water resources management in complex river basins

Effective water resources management programs have always incorporated detailed analyses of hydrological and water quality processes in the upland watershed and downstream waterbody. We have integrated two powerful hydrological and water quality models (SWAT and CE-QUAL-W2) to simulate the combined processes of water quantity and quality both in the upland watershed and downstream waterbody. Whereas the SWAT model outputs water quality variables in its entirety, the CE-QUAL-W2 model requires inputs in various pools of organic matter contents. An intermediate program was developed to extract outputs from SWAT at required subbasin and reach outlets and converts them into acceptable CE-QUAL-W2 inputs. The CE-QUAL-W2 model was later calibrated for various hydrodynamic and water quality simulations in the Cedar Creek Reservoir, TX, USA. The results indicate that the two models are compatible and can be used to assess and manage water resources in complex watersheds comprised of upland watershed and downstream waterbodies.     

A Model for Landscape Planning Under Complex Spatial Conditions

We present a new mathematical programming framework that is adaptable to a variety of spatially explicit landscape problems in environmental investment, conservation, and land-use planning, transport planning, and agriculture. As part of capturing spatial interdependencies, the framework considers decision variables at two levels, finely spaced grid cells and landholdings. We applied the framework to an environmental investment problem using objective functions representing biodiversity and carbon sequestration. We also tested the model to optimize the path of a road through part of the landscape. Using the Nambucca case study in eastern Australia, we applied a hybrid greedy randomised adaptive search procedure (GRASP) to find solutions to the model.     

Hydrologic–Economic Model for Managing Irrigation Intensity in Irrigation Areas under Watertable and Soil Salinity Targets

This paper gives mathematical details and sample applications of SWAGMAN Farm (SWAGMAN, Salt Water and Groundwater Management), a farm-scale hydrologic economic model that integrates agronomic, climatic, irrigation, hydrogeological and economic aspects of irrigated agriculture. The model is capable of determining optimum mix of land use to keep watertable and soil salinity within acceptable limits while maximising the economic returns. Alternatively, the model can simulate water and salt balance and economics of a given cropping preference. Web-based and Geographic Information Systems versions of the model are available for integration with the environmental reporting systems of the irrigation areas.     

Development and Parameterization of a Rain- and Fire-driven Model for Exploring Elephant Effects in African Savannas

We describe the development and parameterization of a grid-based model of African savanna vegetation processes. The model was developed with the objective of exploring elephant effects on the diversity of savanna species and structure, and in this formulation concentrates on the relative cover of grass and woody plants, the vertical structure of the woody plant community, and the distribution of these over space. Grid cells are linked by seed dispersal and fire, and environmental variability is included in the form of stochastic rainfall and fire events. The model was parameterized from an extensive review of the African savanna literature; when available, parameter values varied widely. The most plausible set of parameters produced long-term coexistence between woody plants and grass, with the tree–grass balance being more sensitive to changes in parameters influencing demographic processes and drought incidence and response, while less sensitive to fire regime. There was considerable diversity in the woody structure of savanna systems within the range of uncertainty in tree growth rate parameters. Thus, given the paucity of height growth data regarding woody plant species in southern African savannas, managers of natural areas should be cognizant of different tree species growth and damage response attributes when considering whether to act on perceived elephant threats to vegetation.     

Critical technical elements of state bioassessment programs: a process to evaluate program rigor and comparability

We developed a systematic process to evaluate state/tribal bioassessment programs to provide information about the rigor of the technical approach. This is accomplished via on-site interviews to produce an evaluation that assigns one of four levels of rigor as an outcome. Level 4 is the most rigorous and reflects a technical capacity to accurately determine incremental condition and support management programs. The remaining three levels are less able to assess incremental condition and are appropriate for only some management support needs. Accurately determining impairment and diagnosing pollution-specific stressors are fundamental tasks that states/tribes must accomplish to provide management support. This goal is fulfilled to varying degrees by most states/tribes. The evaluation employs a checklist and a sliding scale of rigor for 13 technical elements. Feedback is provided to each state/tribe via a technical memorandum that describes the technical components of the monitoring program, highlights strengths, and recommends improvements for specific technical issues. This can be used to refine the bioassessment and monitoring programs to better support management programs. The results of 14 state/tribal evaluations are included here. The majority (nine states, one tribe) revealed that most operate at level 2 with developmental activities that will elevate the level of program rigor already underway. Two states operate level 4 programs and each have numeric biocriteria and refined designated uses in their water quality standards. This is the ultimate goal of the process of engaging states in the development of bioassessment programs in the U.S.     

A storm event-based approach to TMDL development

It is vitally important to define the critical condition for a receiving water body in the total maximum daily load (TMDL) development process. One of the major disadvantages of using a continuous simulation approach is that there is no guarantee that the most critical condition will be covered within the subjectively selected representative hydrologic period, which is usually several years depending on the availability of data. Another limitation of the continuous simulation approach, compared to a design storm approach, is the lack of an estimate of the risk involved. Because of the above limitations, a storm event-based critical flow-storm (CFS) approach was previously developed to explicitly address the critical condition as a combination of a prescribed stream flow and a storm event of certain magnitude, both having a certain frequency of occurrence and when combined, would create a critical condition. The CFS approach was tested successfully in a TMDL study for Muddy Creek in Virginia. The present paper reports results of a comparative study on the applicability of the CFS approach in Taiwan. The Dy-yu creek watershed in northern Taiwan differs significantly from Muddy Creek in terms of climate, hydrology, terrain, and other characteristics. Results show that the critical condition for different watersheds might be also different, and that the CFS approach could clearly define that critical condition and should be considered as an alternative method for TMDL development to a continuous simulation approach.     

Investigating Jacaranda mimosifolia tree as biomonitor of atmospheric trace metals

Studies on the use of tree bark as biomonitors for environmental pollutants are still very scarce. We evaluated the reliability of using Jacaranda mimosifolia, a common tree in Tshwane City of South Africa, as a suitable biomonitor of atmospheric trace metals. Bark samples were collected from ten different locations during two sampling periods. The concentrations of the metals were determined by inductively coupled plasma mass spectrometry. The concentrations of the metals were 33.2–1,795 μg/g (Pb), 21.4–210 μg/g (Cu), 68.4–490 μg/g (Zn), 30.6–2,916 μg/g (Cr), 0.12–1.34 μg/g (Cd), and 6.04–68.0 μg/g (V), respectively. The differences obtained for the results from different sites were significant (p?< 0.05). A significant difference was also observed between the two sampling periods. The trace metals concentrations suggested that automobile emissions are a major source of these metals. The study also confirms the suitability of J. mimosifolia as a biomonitor of atmospheric deposition of these metals.     

Characterizing the forest fragmentation of Canada’s national parks

Characterizing the amount and configuration of forests can provide insights into habitat quality, biodiversity, and land use. The establishment of protected areas can be a mechanism for maintaining large, contiguous areas of forests, and the loss and fragmentation of forest habitat is a potential threat to Canada’s national park system. Using the Earth Observation for Sustainable Development of Forests (EOSD) land cover product (EOSD LC 2000), we characterize the circa 2000 forest patterns in 26 of Canada’s national parks and compare these to forest patterns in the ecological units surrounding these parks, referred to as the greater park ecosystem (GPE). Five landscape pattern metrics were analyzed: number of forest patches, mean forest patch size (hectare), standard deviation of forest patch size (hectare), mean forest patch perimeter-to-area ratio (meters per hectare), and edge density of forest patches (meters per hectare). An assumption is often made that forests within park boundaries are less fragmented than the surrounding GPE, as indicated by fewer forest patches, a larger mean forest patch size, less variability in forest patch size, a lower perimeter-to-area ratio, and lower forest edge density. Of the 26 national parks we analyzed, 58% had significantly fewer patches, 46% had a significantly larger mean forest patch size (23% were not significantly different), and 46% had a significantly smaller standard deviation of forest patch size (31% were not significantly different), relative to their GPEs. For forest patch perimeter-to-area ratio and forest edge density, equal proportions of parks had values that were significantly larger or smaller than their respective GPEs and no clear trend emerged. In summary, all the national parks we analyzed, with the exception of the Georgian Bay Islands, were found to be significantly different from their corresponding GPE for at least one of the five metrics assessed, and 50% of the 26 parks were significantly different from their respective GPEs for all of the metrics assessed. The EOSD LC 2000 provides a heretofore unavailable dataset for characterizing broad trends in forest fragmentation in Canada’s national parks and in their surrounding GPEs. The interpretation of forest fragmentation metrics must be guided by the underlying land cover context, as many forested ecosystems in Canada are naturally fragmented due to wetlands and topography. Furthermore, interpretation must also consider the management context, as some parks are designed to preserve fragmented habitats. An analysis of forest pattern such as that described herein provides a baseline, from which changes in fragmentation patterns over time could be monitored, enabled by earth observation data.