The eco-economics and sustainability provide the conceptual framework upon which studies of environmental sciences are based. The main aim of modern conservation biology is to maintain species diversity and abundance, keeping in view, by planting wild crops, the fossil fuels can be replaced by biomass fuel as a renewable energy source. Scientists and people related to urban planning must follow the correct application of principles of population ecology and applied human ecology. Sustainable development has long term impacts on human welfare but, with some limitations and the need for new approaches is required due to continuous global changes. The ultimate level of ecological organization is the ecosystem that involves the interacting organisms in an area and their interactions with their abiotic environment. Our emphasis is on eco- economic growth, in which use of natural resources channeled within social sectors should attain sustainability. The eco-economics is estimated presently with current population data for different countries and its projected population in 2050 based on US Census Bureau’s International data base.

The aim of this study is to develop an innovative pilot plant compact system for decentralized treatment and reuse of domestic wastewater. The design, construction, operation and performance of the system are presented. The system is modular; it could serve from 1,000 to 5,000 capita. The pilot plant comprises of three successive compartments namely; hybrid up flow anaerobic sludge blanket (H-UASB) packed with innovative non-woven polyester fabric (NWPF), inclined plate settler (IPS) and a slow sand filtration unit (SSF). Characterization of NWPF was carried out using scanning election microscope. In addition toxicity test of the packing material was carried out using daphnia magna as a test organism. The NWPF has a specific area of 2000 m2/m3 and an average pore size of 43.8 µm. The overall efficiency of the treatment system, running for almost one year, resulted inconsiderable reductions of COD (86.6%), BOD (90.3%) and TSS (96.8%). In addition, great removal of nutrients and pathogens were also achieved. The results obtained proved the advantage of using the innovative packing material (NWPF) in the UASB reactor. The NWPF have pleated and rough surface, which can retain more biomass rather than the plain surface. Its high surface area and high porosity enhanced the strong adhesion of microbial biomass onto the packing media promoting the effective physical entrapment/adsorption and subsequent bonding between the biomass and media. In conclusion, the proposed treatment system produced a very high quality effluent, which can be applied in rural area and small communities.

Dyes are extensively used in the textile industry because of their wide variety of color shades, ease of application and minimal energy consumption. Disposal of these dyes into the environment causes pollution and serious damage, since they may significantly affect the photosynthetic activity of hydrophytes and also they are toxic to some aquatic organisms. In this study four microorganisms (one Pseudomonas sp. and three Bacillus sp.) were isolated and assayed for their ability to degrade six textile dyes. In order to test the activity of these bacteria on different dyes, experiments were carried out for optimization at different pH, temp and Dye concentration. All the four microorganisms showed maximum dye degradation after 8 days of incubation. The results from present study shows practical application potential of these bacterial species in the biotransformation of various dye effluents that can help to solve the pollution problems caused by textile industries.

The degree of contamination by heavy metals (copper, silver) on some plants of genus Potamogeton L. has been studied. Plants were exposed to metal treatments of Cu and Ag for three weeks. Leaves and stems were harvested for studying anatomy and analyzing metal accumulation. Accumulation of Cu and Ag in all parts of the plant increased significantly with an increase in applied metal concentration Total chlorophyll content and biomass declined progressively with increasing concentrations of the heavy metal. In Ag the plant P.crispus more effective in the total protein reach 2.65%, while in P. perfoliatus was 6.32%, the Cu found the lower effect on total protein research to 7.34% in P.crispus at 15 mg/l concentration and 10.92% in P. perfoliatus compared with Ag treated. Anatomical analyses of stem Potamogeton plants revealed several changes in the Leaves and stems of plants submitted to contaminated treatments. Potamogeton exhibits hydrophytic adaptations which include gradual changes in leaves and stem structure with an increase in metal concentration compared with the control treatment. The leaves of plants exposed to contamination presented modified anatomical characteristics. Exposure to heavy metals leads to a reduction in the size of blade thickness, number of conducting elements, reduced cell size of the epidermis and aerenchyma tissue. Stems undergo changes in size, shape and arrangement of cortical parenchyma cells, plants of the treatment with more contamination had widened cell spaces in the cortex of parenchyma cells, reduced in vascular bundles.