Waste Assimilative Capacity Research Articles

Analysis of Ningxia Hui Autonomous District’s Gray Water Footprint from the Perspective of Water Sustainability

Gray water footprint (GWF) is an effective method to evaluate the degree of water pollution and water quality. It is the amount of freshwater needed to dilute water pollutants to meet ambient water quality standards. Accounting and analyzing the GWF will be significant for promoting an improved water environment and sustainable water ecology in Ningxia Autonomous District. We accounted for the GWF of all cities in Ningxia from 2012 to 2020 and evaluated its spatial-temporal variations by the GWF accounting method proposed by Hoekstra. Then, the Logarithmic Mean Divisia Index (LMDI) method was applied to investigate the contributions of four driving factors: the population scale effect, economic development effect, technological effect, and industrial structure effect. And then, the changes in the GWF in the Ningxia region were analyzed. The results showed that the GWF in the Ningxia region changed from 79.21 × 108 to 29.09 × 108 m3/yr during 2012–2020, making a significant decreasing trend. Among all cities, Wuzhong City contributes the most in terms of the GWF. More specifically, economic development and technology structure are the positive and negative drivers of the GWF, respectively. The water pollution levels in Ningxia (0.49–1.3) indicated that the waste assimilation capacity has fallen short of taking up the pollutant load, which had an unfavorable impact on the groundwater according to actual water quality data. NO3-N and NH3-N are detected in the groundwater throughout the Ningxia region, with the highest NH3-N content in the groundwater in Yinchuan, which almost exceeded the groundwater quality standard of category III. Above all, this study reflected the current water pollution situation better by combining the GWF with actual water quality data in Ningxia. The finding of this study is valuable for addressing water quality threats and developing sustainable development.

Heavy Metal Analysis of Central Cross River, Nigeria using Nile Tilapia (Oreochromis niloticus) and Water as Bio-indicators

The most of the fish consumed in the Cross River State are brought from Cross River, the quality characteristics of such fishes are foremost importance. Therefore, this study was carried out to provide information on heavy metal concentrations in the water and muscles of Nile tilapia (Oreochromis niloticus), a commercial fish species available in the markets of Cross River State and to make people aware of the possible health risk associated with their consumption. Samples were collected from nine sites along the length of the river and were designated as Stations A (Itigidi), B (Ekori), C (Ahaha), D (Ofombogha), E (Obubra), F (Ochong), G (Alesi), H (Okuni) and I (Ikom). The heavy metal profile (Pb, Mn, Zn, Cd, Cr, Ni, Cu, Fe, Al and Co) was assessed using Atomic Absorption Spectrophotometer. Results of metal profile observed were in order of magnitude in Itigidigi > Ekori > Ahaha > Ofombogha > Ochong >Obubra > Alesi > Okuni > Ikom, while the concentration of heavy metals in the sampling stations were in the order of magnitude of fish > water. Most of the metal concentrations were below the maximum allowable levels set by the WHO, FEPA, and USEPA except zinc with mean concentration of 0.27±0.047μg.g-1 in fish and 0.31±0.18μg.g-1 in water which were above recommended limit of 0.0766μg.g-1 of USEPA at Itigidi and Ekori respectively . This implied that the waste assimilation capacity of the river is high, a phenomenon that could be ascribed to continuous water exchange, dilution, and sedimentation. This is an indication that an urban and industrial waste discharged into the Central Cross River has a significant effect on the ecological balance of the river. Thus, fish species harvested from the river may be safe for human consumption.

Insights into water sustainability from a grey water footprint perspective in an irrigated region of the Yellow River Basin

Water sustainability is imperative for socio-economic development. The grey water footprint (GWF) is a useful indicator for quantifying how human activities influence freshwater systems. This study identified the change in GWF for Yinchuan City, an agricultural region in the Yellow River Basin, by the validation of acquired water-quality data. The driving forces of the GWF were analyzed using the logarithmic mean division index (LMDI) decomposition method. The results indicated that the total GWF showed a declining trend during the study period between 2002 and 2017 within the range of 12.6–21.5 × 108 m3/yr. The agricultural GWF had a relatively stable contribution (30–40%), and the focus should be on the increased proportion of domestic sector in this irrigated region. Economic development and technology effects were the dominant negative and positive factors, respectively, behind the decline in GWF. Although the water pollution levels (0.06–0.12) indicating that the waste assimilation capacity was sufficient to take up the pollutant load, the effect of pollution load on groundwater was cause for concern based on the actual water-quality data. A significant increase in NO3–N in the phreatic water was detected between 2003 and 2013. The dominance of NH4–N for the water supply wells in confined aquifers hinted at the deteriorating water quality, which was attributed to the aquifer leakage under pumping conditions. This study better reflected the current water pollution situation by combining GWF with understanding of the hydrological cycle and the actual water-quality data. Findings in this study will be valuable for addressing water quality threats and to develop sustainability strategies for local authorities.

Resource Scarcity and Sustainability—The Shapes Have Shifted but the Stakes Keep Rising

The objective is to provide an interpretive reading of the literature in resource scarcity and sustainability theory from the nineteenth century to the present time, focusing on shifts that have occurred in problem definition, conceptual framing, research tools applied, findings, and their implications. My reading shows, as one would expect, that the discourse has become more technical and the analysis more sophisticated; special cases have been incorporated into the mainstream of theory; and, where relevant, dynamic formulations have largely supplanted static analysis. However, that is barely scratching the surface. Here, I focus on more fundamental shifts. Exhaustible and renewable resource analyses were incorporated into the mainstream theory of financial and capital markets. Parallels between the resources and environmental spheres were discovered: market failure concepts, fundamental to environmental policy, found applications in the resources sector (e.g., fisheries), and renewable resource management concepts and approaches (e.g., waste assimilation capacity) were adopted in environmental policy. To motivate sustainability theory and assessment, there has been a foundational problem shift from restraining human greed to dealing with risk viewed as chance of harm, and a newfound willingness to look beyond stochastic risk to uncertainty, ambiguity, and gross ignorance. Newtonian dynamics, which seeks a stable equilibrium following a shock, gave way to a new dynamics of complexity that valued resilience in the face of shocks, warned of potential for regime shifts, and focused on the possibility of systemic collapse and recovery, perhaps incomplete. New concepts of sustainability (a safe minimum standard of conservation, the precautionary principle, and planetary boundaries) emerged, along with hybrid approaches such as WS-plus which treats weak sustainability (WS) as the default but may impose strong sustainability restrictions on a few essential but threatened resources. The strong sustainability objective has evolved from maintaining baseline flows of resource services to safety defined as minimizing the chance of irreversible collapse. New tools for management and policy (sustainability indicators and downscaled planetary boundaries) have proliferated, and still struggle to keep up with the emerging understanding of complex systems.

Biochemical Oxygen Demand, Nitrogen, Phosphorus and Navigational Carrying Capacities of Bengoh Reservoir for Potential Aquaculture and Recreational Developments

This paper quantifies the biochemical oxygen demand (BOD), nitrogen (N), phosphorus (P) and navigational carrying capacities of Bengoh Reservoir for potential fish cage culture and recreational developments. The pollutant degradation coefficients (k) and pollutant carrying capacities (tons/day) of the reservoir were determined. The computed pollutant degradation coefficients were primarily based on the hydrological information of the catchment, hydraulic and operational details of the dam, and the targeted water quality standards of the river-connected Bengoh Reservoir. The maximum allowable pollutant loading rate (tons/year) defines the reservoir’s maximum Waste Assimilative Capacity (WAC) on specific pollutants (BOD, N and P), while in compliance to the targeted benchmark with the receivable pollutant loadings. It was found that the current BOD, TN and TP loading rates are 0.308 ton/day, 0.119 ton/day and 0.114 ton/day, respectively. To comply with Class I Standards of the National Water Quality Standards of Malaysia (NWQSM), the Maximum Allowable Loading Rates of BOD can be as high as 92.24 tons/day as compared to the current loading rate of 0.308 ton/day, maximum TN loading of 116.63 tons/day versus current 0.119 ton/day, and maximum TP loading at 125.54 tons/day versus current 0.114 ton/day. It was also found that the maximum number 218 cages (225 fish/cage) of Tilapia would be allowed in Bengoh Reservoir so as to comply with Class I of NWQSM. Based on the peak level of the reservoir recreational types of use in demand and the mix of public and private access, the navigational carrying capacity of the reservoir was estimated to be about 130 boats.

Application of Export Coefficient Model and QUAL2K for Water Environmental Management in a Rural Watershed

Water quality deterioration caused by excessive nutrient discharge from various point and non-point sources are a global challenge. Understanding the pollution sources and their respective contribution is the prerequisite for environmental planning, management and restoration. In this study, the influence of complex pollution sources on the water quality of the Dengsha River watershed in Dalian, China, was investigated. The export coefficient method was coupled with the QUAL2K water quality model to estimate the loads of ammonia nitrogen (NH4-N) and total phosphorus (TP) from different sources, and to explore their respective contributions. Results indicated that animal feedlot and crop production were major sources for NH4-N load, and crop production, soil erosion and animal feedlot are the largest three sources of TP load with an annual total contribution of 98.4%. The pollutant load exhibited an intra-annual variation mainly due to the seasonality of rainfall and anthropogenic agricultural activities. The overall waste assimilation capacity (WAC) is overloaded and suggestions for water pollution control and treatment regarding each pollution source were proposed. This study addressed a new application of QUAL2K model coupled with the export coefficient model for watershed managers towards a sustainable water environmental management, and can therefore be a reference example for other small and medium-sized rural watersheds.

The Necessary Paradigm Shift in Sustainable Business Practice Part 1: The Framework

The historical prevailing paradigms or perceptions are implicit or explicit beliefs that mould our behaviour. Business takes these on in the same way as society. It is not surprising therefore that Management has behaved as if there was infinite resource availability and waste assimilation capacity in nature. Consequently, the loose relationship between economics and the environment, where business accepted one-to-one pollution control strategy supported by legislative controls is a direct consequence of this historical legacy. This dominates industrial thinking in relation to defining good sustainable business practice. 
 
 This paper reviews the perceptions that have arisen from these historical paradigms, “legacies of the past”, giving a reminder of the facts and truths that have somehow become lost in today’s thinking. It goes on to present the set of paradigms that have to be taken on board by corporate management if it is to construct a framework that will allow it to adopt strategic Sustainable Development policies.

Applying grey water footprint assessment to achieve environmental sustainability within a nation under intensive agriculture: a high-resolution assessment for common agrochemicals and crops

Achieving safer environment under intensive agriculture highly depends on input resource management. This research is the first grey water footprint (WF) assessment in which the field-scale heterogeneities in input data are considered to provide new insights for achieving sustainable environment under dense farming. For a 10-year period over 2005–2015, grey WF accounting and impact assessment was carried out, together with sensitivity and uncertainty analysis, for a wide range of agrochemicals commonly applied to the agricultural soils in Iran. Given results were then applied to provide new applicable solutions for reducing the overall pollutant loaded to freshwater bodies from diffuse sources. The 10-year average of the given results showed that with an overall load of 77.1 thousand t year−1, N was the most critical substance among various agrochemicals, especially within the irrigated lands, where are the origin of 83.1% of loaded N to freshwater bodies. Cereals, both irrigated and rainfed, always had the largest contribution in the overall pollutants loaded to water bodies. At the national sale, 48.2 billion m3 year−1 water is annually required to take up the N pollution loads, which is 26.8% less than actual runoff within the country. While the national-scale water pollutant level (WPL) was 0.7, the high-resolution assessment indicated the existence of local polluted area with WPL > 1 in 42.8% of the country, 96% of which located within the arid and semi-arid regions. In these areas, the river’s waste assimilation capacity has been overused by the factors of 1–32.8. Based on the quantitative impact assessment, the overall N-related grey WFs may be reduced by 47% if grey WFs are lowered down to the benchmark levels set at the 25th percentile of crop production, by 9.1% if crops’ yield is improved by 10%, and by 27.8% if N-application rates are reduced to the optimal rate. In addition, regional prioritizing of cropping pattern based on their grey WFs may result in an expressive reduction in WPL due to the large diversity in grey WFs among crops and regions. Based on the results, it could be concluded that, with a 10–16.1% uncertainties, a high-resolution local-scale grey WF assessment is a promising way to achieve safer agricultural environment in a dense-farming country.

Quantification of micropollutants in some water sources in northern Tanzania

The loading of micropollutants in freshwater ecosystems to levels exceeding their waste assimilative capacity is a threat to both ecology of the ecosystems and health of the resource users. Some chemical species are of much concern due to their persistence, bioaccumulative and toxicity nature, even at trace levels, while others are of concern due to their contribution to eutrophication, oxygen depletion and other disruptive changes. Despite contamination threats from human activities around catchment areas in Tanzania, specific extent of the impacts are rather not well investigated. In this work, we quantified concentration levels of some major elements, trace elements, dissolved inorganic ions, nutrients and organochlorine pesticide residues in river water and sediments from northern Tanzania. Information on land use practices in the area, which represents potential sources of contamination, was gathered. Samples were collected from pre-selected stations in two different seasons and characterized for physico-chemical parameters. Preparation and instrumental analysis of samples was done by standard analytical protocols. Obtained results indicated contamination by some micropollutants, including some dissolved ionic species in water: Na + (> 200 mg/l), K + (> 25 mg/l), Mg 2+ (> 50 mg/l) and NO 3 – –N (> 80 mg/l). High concentrations of some toxic metals were also measured in sediment samples, including V (325 mg/kg), Cr (270 mg/kg), Cu (114 mg/kg), Ni (85 mg/l) and Zn (355 mg/kg). Low levels of organochlorine pesticide residues were measured. Concentration levels were compared to water and sediment quality guidelines to establish their ecotoxicological risk implications. Keywords: Micropollutants; Surface water; Sediments; Contamination; Tanzania

An integrated use of histological and ultra-structural biomarkers in Mugil cephalus for assessing heavy metal pollution in east Berbice-Corentyne, Guyana

Bioaccumulation of heavy metals and its associated histopathological perturbations were studied in various tissues of Mugil cephalus collected from polluted and compared with the fish collected from less polluted of Corentyne coast. The concentration of copper, lead, zinc, cadmium, manganese and iron were quantified in gills, liver and muscle. The results showed marked differences between the two sites as well as significant variations within the tissues. The decreasing trend of metals in the tissues of fish sampled from both polluted and less polluted sites was in the order of Fe >Mn > Zn > Cu > Pb > Cd. Overall, the highest metal concentrations were found in the fish collected from polluted site. The accumulation in the gills and liver of M. cephalus was found to be quite high in comparison with the muscle. These tissues were further investigated by light and electron microscopy and the results were compared with the reference site (Less polluted). The presence of large lipid droplets in liver and increase of mucous cell in gill were some of the most noticeable alterations observed and were related to heavy metal contaminates. It is concluded that histopathological and ultrastructural biomarkers provide reliable and discriminatory data to augment heavy metal pollution in polluted site of Coretyne coast. Therefore, long-term monitoring is necessary to assess the untreated waste water discharged directly and indirectly into the water ways of Corentyne coast led to a reduction in waste assimilative capacity of the coastal marine waters, which provide accurate, reliable measurements of environmental quality.

The evaluation of environmental capacity: Evidence in Hunan province of China

Environmental capacity paves the foundation for sustainable economic development. As the vital growth pole in the Rise Strategy of Central China, the environmental and economic construction of Hunan province proves to have enormous demonstration effect. In order to better understand the environmental condition in Hunan province, this study combines the information entropy theory and ecological comprehensive index to measure the environmental capacity of 14 administration divisions in Hunan province and 30 provinces across China in 2013. The results indicate that, first of all, the average environmental capacity of 14 administration divisions in Hunan province is relatively lower, i.e., 0.39. Second, Chang-Zhu-Tan city cluster in Hunan province exerts limited radiative and guiding effect on its surroundings; in particular, Xiangtan possesses a notably lower environmental capacity than other two cities, which hampers the integration process. Third, among the four types of environmental capacities concerned, i.e., population capacity, land capacity, resource capacity and waste assimilative capacity, waste assimilative capacity takes up the biggest weight, i.e., 0.31, indicating the most important role in environmental improvement. Finally, the environmental capacity of Hunan province ranks the 24th among the 30 provinces in China and the last in central China. Hunan should pay special attention to the expansion of waste assimilate capacity, so as to promote the overall environmental capacity.

Southwest monsoon influences the water quality and waste assimilative capacity in the Mandovi estuary (Goa state, India)

The monsoon-dominated Mandovi estuary is located in Goa state – a global tourist destination along the centralwest coast of India. In addition to factor analyses of water quality data, the water quality index (WQI), trophic state index (TSI) and percentage of freshwater volume in the estuary are calculated in order to infer the general waste assimilative capacity and prevailing water quality conditions. Factor analysis showed a dominance of PO4–P, NO2–N, NH3–N, total suspended solids (TSS) and turbidity during southwest (SW) monsoon relative to other seasons. The WQI suggested that an increase in nutrients, turbidity and TSS during SW monsoon increase the WQI values beyond 2, rendering the water at some locations slightly polluted. During pre-monsoon, considerable increase in the WQI is observed at all the upstream stations rendering slightly polluted water at these stations. The TSI showed an average value of 46.95 during SW monsoon, 42.43 during post-monsoon and 48.42 during the pre-monsoon seasons, suggesting better productivity level during pre-monsoon, followed by SW monsoon, but the least during the post-monsoon. All the seasons, however, indicated a mesotrophic condition in the estuary and the assimilative capacity of the estuary is found to be in good to fairly good state (pre-monsoon < SW monsoon < post-monsoon).

Determination of waste assimilative capacity (WAC) of rivers located within the Desaru Region, Johor

Desaru is a popular tourist destination located on the east coast of the state of Johor. The area has been identified for further development to enhance tourism. This presents a pollution risk to its surrounding watercourses. The purpose of this study was to assess the potential risk of contamination towards rivers located in the crux of the development region, namely the Terumpah, Che Minah, Semangar, Beluntu, Penawar Besar, and Mertang Besar Rivers. Water quality and hydraulic measurements were made at these rivers, with the intention of developing a numerical model. The model results showed deterioration in BOD5 and NH3-N in the Semangar River, up to 4.0 mg/dm3 and 0.34 mg/dm3, respectively. The Beluntu River experienced the highest degradation, to about 14.0 mg/dm3 of BOD5 and 0.8 mg/dm3 of NH3-N. The waste assimilative capacity (WAC) for the Matang Besar, Che Minah and Beluntu Rivers were very limited, with a class III BOD5 limit of 15, 43, and 10 kg/day, respectively, whereas the Terumpah River is not able to accept any BOD load without breaching the same threshold

The added value of water footprint assessment for national water policy: a case study for Morocco.

A Water Footprint Assessment is carried out for Morocco, mapping the water footprint of different activities at river basin and monthly scale, distinguishing between surface- and groundwater. The paper aims to demonstrate the added value of detailed analysis of the human water footprint within a country and thorough assessment of the virtual water flows leaving and entering a country for formulating national water policy. Green, blue and grey water footprint estimates and virtual water flows are mainly derived from a previous grid-based (5×5 arc minute) global study for the period 1996–2005. These estimates are placed in the context of monthly natural runoff and waste assimilation capacity per river basin derived from Moroccan data sources. The study finds that: (i) evaporation from storage reservoirs is the second largest form of blue water consumption in Morocco, after irrigated crop production; (ii) Morocco’s water and land resources are mainly used to produce relatively low-value (in US$/m3 and US$/ha) crops such as cereals, olives and almonds; (iii) most of the virtual water export from Morocco relates to the export of products with a relatively low economic water productivity (in US$/m3); (iv) blue water scarcity on a monthly scale is severe in all river basins and pressure on groundwater resources by abstractions and nitrate pollution is considerable in most basins; (v) the estimated potential water savings by partial relocation of crops to basins where they consume less water and by reducing water footprints of crops down to benchmark levels are significant compared to demand reducing and supply increasing measures considered in Morocco’s national water strategy.

Waste Assimilative Capacity of Coastal Waters along Mumbai Mega City, West Coast of India Using MIKE‐21 and WASP Simulation Models

Coastal waters are the ultimate receivers of the organic waste materials generated by upstream cities and towns. This waste can cause dissolved oxygen depletion due to increased oxygen demand, affecting the natural ability of water bodies to withstand certain amount of pollution – the waste assimilative capacity. The pollution load (biochemical oxygen demand) calculated using the population equivalent value of 0.225 m3/day for the present Mumbai population of 13 million is 731 250 kg/day. Simulations using MIKE‐21 and WASP models along with the observed water quality data as well as current meter data indicated that the coastal waters can withstand the present pollution load since the simulated biochemical oxygen demand was with in the range of 0.2–1.5 mg/L, the National Standard limits. A projected population increase exceeded the target biochemical oxygen demand value of 2 mg/L, indicating the deterioration of ambient quality of coastal waters. Waste assimilative capacity studies are crucial in the present‐day regional, as well as global issues, such as population explosion, water shortage, and climate change.

Heavy metal profile of water, sediment and freshwater cat fish, Chrysichthys nigrodigitatus (Siluriformes: Bagridae), of Cross River, Nigeria

Cross River serves as a major source of drinking water, transportation, agricultural activities and fishing in Cross River State, Nigeria. Since there is no formal control of effluents discharged into the river, it is important to monitor the levels of metals contaminants in it, thus assessing its suitability for domestic and agricultural use. In order to determine this, three sampling stations designated as Ikom (Station I), Obubra Ogada (Station II) and Calabar (Station III) were randomly selected to study. For this, ten samples of the freshwater Silver Catfish (Chryshchythys nigrogitatus) (29.4-39.5cm SL, 310-510g), sediment and water were collected from each sampling Station from June 2009-June 2010. The heavy metals profiles ofZn, Cu, Fe, Co, Pb, Cd and Cr, in water, sediments and fish muscle were analyzed by atomic absorption spectrophotometry (AAS). In fish, the heavy metals concentration was found to be Cu>Fe>Zn>Cu>Pb>Cd>Co; the highest mean concentration of Copper (0.297 +/- 0.022 microg/g), Cadmium (0.011 +/- 0.007 microg/g), Iron (0.371 +/- 0.489 microg/g), Lead (0.008 +/- 0.008 microg/g), were determined for the fish. In water, the order was found to be Fe>Pb>Zn>Cu>Cr>Cd>Co; the highest mean concentration of Iron (0.009 +/- 0.00) microg/g), Copper (0.015 +/- 0.01 microg/g), Lead (0.0002 +/- 0.00 microg/g) Cadmium (0.0006 +/- 0.001 microg/g), Zinc (0.0036 +/- 0.003 microg/g), were observed in the surface water, respectively. The highest mean concentration of Copper (0.037 +/- 0.03 microg/g), Iron (0.053 +/- 0.04 microg/g), Lead (0.0002 +/- 0.00 microg/g), Cobalt (0.0002 +/- 0.00 microg/g), Cadmium (0.0006 +/- 0.001 microg/g) and Zinc (.009 +/- 0.0015 microg/g) was observed in the bottom water. In sediments, the concentration order found was Zn>Fe>Cu>Pb>Co>Cd; the highest mean concentration of 0.057 +/- 0.04 microg/g, 0.043 +/- 0.03 microg/g, 0.0006 +/- 0.00 microg/g, 0.0002 +/- 0.00 microg/g, 0.0009 +/- 0.00 microg/g, 0.099 +/- 0.00404 microg/g in Iron, Copper, Lead, Cobalt, Cadmium and Zinc were observed in the sediment, respectively; Chromium was not detected in the sediment for the whole sampling area. Most of the heavy metals were below the maximum allowable levels set by the WHO, FEPA and USEPA, except Zinc which mean concentration of 0.099 +/- 0.00404 microg/g was above the recommended limit of 0.0766 microg/g of USEPA in the sediment at Ikom. This implies that the waste assimilation capacity of the river is high, a phenomenon that could be ascribed to dilution, sedimentation and continuous water exchange. This is an indication that an urban and industrial waste discharged into the Cross River has a significant effect on the ecological balance of the river. Thus fish species from the Cross River harvested are safe for human consumption.

Spectroscopic analyses of pollutants in water, sediment and fish

Water ways in Egypt is suffering from continual discharge without adequate treatment especially in the Delta and greater Cairo area. Accordingly water, sediments and catfishes were collected from El Mouheet El Youmna drain in Giza. Cd, Cr, Pb and Zn were determined furthermore the molecular structure of sediment and catfish were conducted with FTIR spectroscopy. Although studied metals were lower in water, higher values are recorded in sediment and catfish samples. FTIR shows possible interaction among metals and organic structures mainly proteins. The bioaccumulation of Pb and Cd proportion was significantly increased in the liver tissues of catfish. A correlation coefficient among sediment and fish liver metals accumulation exist. This infers that the waste assimilation capacity for the drain is high, a phenomena that could be ascribed to dilution, sedimentation and continual water exchange. Furthermore, the genotoxicity affect in catfish genomic corroborates the genus diagnostic markers which attributed to long pollution. This is an indication that agriculture and industrial wastes discharged into the drain has badly a significant effect on the ecological balance.

SIFNP: Simulation-Based Interval-Fuzzy Nonlinear Programming for Seasonal Planning of Stream Water Quality Management

A simulation-based interval-fuzzy nonlinear programming (SIFNP) approach was developed for seasonal planning of stream water quality management. The techniques of inexact modeling, nonlinear programming, and interval-fuzzy optimization were incorporated within a general framework. Based on a multi-segment stream water quality simulation model, dynamic waste assimilative capacity of a river system within a multi-season context was considered in the optimization process. The method could not only address complexities of various system uncertainties but also tackle nonlinear environmental–economic interrelationships in water quality management problems. In addition, interval-fuzzy numbers were introduced to reflect the dual uncertainties, i.e., imprecision associated with fixing the lower and upper bounds of membership functions. The proposed method was applied to a case of water quality management in the Guoyang section of the Guo River in China. Interval solutions reflecting the inherent uncertainties were generated, and a spectrum of cost-effective schemes for seasonal water quality management could thus be obtained by adjusting different combinations of the decision variables within their solution intervals. The results indicated that SIFNP could effectively communicate dual uncertainties into the optimization process and help decision makers to identify desired options under various complexities of system components.

INTEGRATED MANAGEMENT OF AGRICULTURE DRAINAGE WATER REUSE TO NOURISH NUBARIA CANAL

In this study, the quality of the Nubaria canal water was investigated before and after mixing drainage water with Nubaria canal. Flow and water quality profiles have been estimated along the canal through the mathematical model, QUAL2K. The model has been calibrated according to the field data collected during summer and winter of the year 2007. The study included electrical conductively (EC), Biological Oxygen Demand (BOD) and ammonia (NH3). From the results obtained, the QUAL2K model appears to be useful for estimating water quality of Nubaria canal. Dynamic management is the most appropriate solution for controlling water quantity and quality of drainage water expected to be reused through mixing with Nubaria canal. Moreover, the salt and waste assimilative capacity of a canal could be calculated. Reusing of mix project drainage water, by discharge of 0.50 million m3/d does not affect the Nubaria water canal. There are clear effects in the Nubaria canal water today due to drainage water specially drain 3.

The need to move to a qualitatively-improving steady-state economy to resolve the climate change dilemma

The climate change issue is a policy concern that falls within the broader issue of sustainable development. Sustainable development means different things to different people. Green economists argue that sustainable development involves the adequate provisioning for people everywhere, of other species, and of the planet and its constituent systems. Essentially concurring with this view, ecological economists believe that achieving sustainable development requires the resolution of three major policy goals: (a) sustainable scale (ensuring the scale of the human economy relative to the supporting ecosphere is ecologically sustainable); (b) distributional equity (ensuring the distribution of income and wealth is equitable both within and across nations); and (c) allocative efficiency (ensuring the resources entering an economic system are allocated to their best possible use). Human-induced climate change is primarily the result of a failure to resolve policy goal (a). That is, in a world where economic activity is largely driven by the use of hydrocarbon (fossil) fuels, climate change is a consequence of the rate of resource throughput exceeding the waste assimilative capacity of the global ecosphere. Should the global economy continue to grow at its current rate, it is unlikely that renewable energy will be available in the quantities needed to reduce climate change-inducing emissions. For this and other reasons, the world's high-income countries must immediately make the transition to a steady-state economy – in effect, a non-growing but qualitatively-improving economy maintained by a declining rate of resource throughput. The movement by high-income countries to a steady-state economy would not only reverse the recent decline in their own well-being, it would provide low-income countries with the room required to enjoy a spurt of welfare-increasing growth before they, too, must make the transition to a qualitatively-improving steady-state economy.