Selected Water Bodies Research Articles

A Fusion Approach for Water Area Classification Using Visible, Near Infrared and Synthetic Aperture Radar for South Asian Conditions

Consistent estimation of water surface area from remote sensing remains challenging in regions such as South Asia with vegetation, mountainous topography, and persistent monsoonal cloud cover. High-resolution optical imagery, which is often used for global inundation mapping, is highly impacted by clouds, while synthetic aperture radar (SAR) imagery is not impacted by clouds and is affected by both topographic layover and vegetation. Here, we compare and contrast inundation extent measurements from visible (Landsat-8 and Sentinel-2) and SAR (Sentinel-1) imagery. Each data type (wavelength) has complementary strengths and weaknesses which were gauged separately over selected water bodies in Bangladesh. High-resolution cloud-free PlanetScope imagery at 3-m resolution was used as a reference to check the accuracy of each technique and data type. Next, the optical and radar images were fused for a rule-based water area classification algorithm to derive the optimal decision for the water mask. Results indicate that the fusion approach can improve the overall accuracy by up to 3.8%, 18.2%, and 8.3% during the wet season over using the individual products of Landsat8, Sentinel-1, and Sentinel-2, respectively, at three sites, while providing increased observational frequency. The fusion-derived products resulted in overall accuracy ranging from 85.8% to 98.7% and Kappa coefficient varying from 0.61 to 0.83. The proposed SAR-visible fusion technique has potential for improving satellite-based surface water monitoring and storage changes, especially for smaller water bodies in humid tropical climate of South Asia.

Developing and Evaluating Multi-Scale Map Styles: Creating a Multi-Scale Legend

Abstract. In recent years, the usage of zoomable maps strongly increased. The development of small and cheap electronic devices with wireless internet connection such as smartphones and tablets has made maps nowadays to a crucial part of everyday life. For the navigation and orientation, the user often uses zoomable maps (Muehlenhaus, 2014). Currently the technological development controls the map design and less cartographic design rules, which leads to the impress those current maps have a lower graphic quality. A sample for this trend is the new vector tile based maps, which offer the advantage of rotatable, multilingual maps build on one database (Martinelli and Roth, 2016). There is a need for the development of cartographic design guidelines to guarantee consistent map readability over all zoom levels. The infinitely zoomable maps especially vector maps intensify this development. Analog maps had one specific scale, while a series of topographic maps were offered in manageable number of scales in comparison to OpenStreetMaps 20 zoom levels for raster tiles (Anon, 2019). Raster web maps had a number of predefined zoom levels, while vector maps offer the possibility of continuous zooming. This fact clarifies the requirement of research and development of rules for such types of maps. A first important task for the fulfilment of this objective is the evaluation of a multi-scale map styles. For this task, we developed the concept of a multi-scale legend. This new tool should help cartographers and designer to create, modify and improve multi-scale map styles. It can help to explore existing map styles, identify inconsistencies and support the design process. We decided to use the legend due to the abstraction of the map style from map content. For visualization of the scale-dependencies for each feature in a row, the scale/zoom level changes in each column. In combination with other map features and zoom levels results a two-dimensional matrix showing the scale-dependent visualization. This legend matrix shows the map features in every zoom level, which allows reaching an overview of the symbolization of features over several scales. In this way, it is possible to check how consistent a map style is in one zoom level as well as over a set of zoom levels. Figure 1 shows an example for a legend matrix using the OpenStreetMap Carto style: the representation of selected water bodies depending on the scale is illustrated. Streams and springs always occur together within the same zoom levels. In contrast to the rivers, the width of the streams remains nearly constant across the different scales. It is also visible that the color for the spring differs from the other water features. A multi-scale legend offers the possibility of grouping feature classes by topics (e.g. water bodies, vegetation and road network) as in the example. Other possibilities are geometry, color or occurrence in similar zoom levels. This can help in the search for errors, in the identification of breaks in the symbolization and in the development of continuous symbolization. The result is similar but more illustrative than the ScaleMaster (Brewer and Buttenfield, 2007, 2010), which is a diagram describing how feature classes are visualized depending from scale. Benefits of this legend are clarification of scale depended visualizations and the graphic implementation of design guidelines. A challenge is the implementation for different map styles due to the associated effort and the resulting sometimes very large overviews. An on-going technological development takes place, wherefore cartographers should upgrade the design guidelines and methods for the production of current technological, well-looking maps. With the multi-scale legend, we provided a smart legend for a zoomable map. Nevertheless, these new ideas we have developed need more research and should always take the map purpose in account. Further, we would like to apply the multi-scale legend on existing map styles to reach more information about how these styles are working. In addition, we will further develop the multi-scale legend to a documentation of the creation of the map, showing how data is generalized and visualized.

Economic Appraisal of Water-Ecosystem in Jammu and Kashmir: India

Aims: The aims of the current paper is to provide a comparative analysis of the water ecosystem in the state of Jammu & Kashmir in India and to highlight economic potentiality of the two nerve tributaries; “Dal Lake” and “River Jhelum” to the farmers and other communities of the Kashmiri society.
 Study Design: The temperate region of Kashmir valley is bestowed with many water bodies in the form of springs, lakes and rivers. Kashmir region is world famous for its lakes viz; “Dal Lake”, “Wulur Lake”, “Mansbal Lake”, “Anchar Lake”, “Nigeen Lake”; springs viz; Kokarnag, Verinag, Achabal and “River Jhelum” etc. “Dal Lake” and “River Jhelum” are known to be the nerve tributaries of the valley and various communities are dependent on these water bodies for their livelihood.
 Methodology: Contingent valuation method and willingness to pay techniques were used to analyse the data and interpret the results.
 Results: The results revealed that economic value associated with the selected water bodies was worth millions of US$. Most of the population in the valley depends on these water bodies for their livelihood. In addition, the results reveal that over the years, pollution and encroachment of these water bodies has increased manifold reducing the width, depth and recreational value of these water bodies. Though every stakeholder is willing to pay for the restoration of these water bodies, however, little or no attention is being paid by the local government towards their, management, sustenance and conservation.
 Conclusion: The study concludes that over the years, due to growth of population in the valley along with the ever increasing influx of floating population in terms of tourist arrivals, the selected water bodies (Dal Lake & River Jhelum) came under heavy stress, culminating into the deterioration of their aesthetic and recreational value besides drastic reduction in their revenue generation for their poor water quality and mismanagement. The restoration of these water bodies, which in addition of providing employment to the stakeholders in huge numbers also generate revenue worth millions of US$, demands devising a pragmatic policy by the government towards their conservation and restoration of their lost glory through efficient management and monitoring system.

Food and Feeding Behaviour of Kingfishers (Family: Alcedinidae) in Selected Water Bodies in Osun State, Nigeria

Food and Feeding Behaviour of Kingfishers (Family: Alcedinidae) in Selected Water Bodies in Osun State, Nigeria

A preliminary study on Naegleria species in water bodies of Kurunegala district, Sri Lanka

Introduction and Objective: Species belonging to the genus Naegleria are free-living ubiquitous protozoa. They have been isolated from most regions of the world. N. fowleri causes an acute, fulminant and rapidly fatal infection involving the central nervous system (CNS) in humans. It is known as primary amoebic meningoencephalitis (PAM). Infection is generally acquired while swimming, diving and total submersion for bathing in freshwater-lakes and ponds. Many inland fresh water bodies are present in Sri Lanka. These water bodies are frequently used by people for their daily needs. However, studies have not yet been conducted to determine the prevalence of Naegleria species occurring in local water bodies. The present study was therefore, carried out to isolate Naegleria species from selected water bodies located in four Divisional Secretariat (DS) divisions in the Kurunegala district, Sri Lanka. Methods: Two different sites (clear and turbid water) of each tank were selected for sampling. Two water samples (surface water and deep water) were collected from each site (4 samples from one tank). Altogether, eighty water samples were collected from 20 tanks. Culture, enflagellation test and staining were done to detect Naegleria species. ArcGIS 10.3 and MINITAB (14) software were used for the data analysis. Results: Flagella transformation was observed in 19 (47.5%) surface water samples and 11 (27.5%) deep water samples. Of 20 tanks, 10 were positive for Naegleria species. Conclusions: Findings of the present study suggest that more specific genotyping studies are needed to confirm the presence of pathogenic N. fowleri in the study area.

FEASIBILITY INVESTIGATION ON SINGLE PHOTON LIDAR BASED WATER SURFACE MAPPING

Abstract. The recent advent of single photon sensitive airborne LiDAR (Light Detection And Ranging) sensors has enabled higher areal coverage performance at the price of an increased outlier rate and a lower ranging accuracy compared to conventional Multi-Photon LiDAR. Single Photon LiDAR, in particular, uses green laser light capable of penetrating clear shallow water. Although primarily designed for large area topographic mapping, the technique can also be used for mapping the water surface and shallow water bathymetry. In this contribution we investigate the capability of Single Photon LiDAR for large area mapping of water surface heights. While interface returns from conventional green-only bathymetric sensors generally suffer from water level underestimation due to the water penetration capabilities of green laser radiation, the specific questions are, if Single Photon LiDAR (i) is less affected by this well known effect due to the high receiver sensitivity and (ii) consequently delivers a higher number of water surface echoes. The topic is addressed empirically in a case study by comparing the water surface responses of Single Photon LiDAR (Navarra, Spain) and Multi-Photon Topo-Bathymetric LiDAR (Neubacher Au, Austria) for selected water bodies with a horizontal water surface (reservoirs, ponds). Although flown at different altitudes, both datasets are well comparable as they exhibit the same strip point density of ca. 14 points/m2. The expected superiority of Single Photon LiDAR over conventional green-only bathymetric LiDAR for mapping water surfaces could not be verified in this investigation. While both datasets show good agreement compared to a reference water level when aggregating points into cells of 10 × 10 m2 (mean deviations < 5 cm), higher resolution Single Photon LiDAR based water surface models (grid size 1–5 m) show a systematic water level underestimation of 5–20 cm. However, independently measured ground truth observations and simultaneous data acquisition of the same area with both techniques are necessary to verify the results.

Monitoring of Nuclear Abnormality Frequencies as Indicators of Environmental Pollution in Peripheral Erythrocytes of Labeo rohita Reared in Lakes of Bangalore

The present study was aimed to evaluate genotoxicity in peripheral erythrocytes of Labeo rohita reared in two lakes viz., Vengaiah lake - sewage polluted (Lake A) and Yellamallappa Chetty lake - industrially polluted (Lake B) of Bangalore. To assess the micronuclei and nuclear abnormalities in such erythrocytes, blood samples were collected from heart of the freshwater fish, L. rohita anesthetized by MS222. The results were compared with the fish reared in the Hebbal fish farm (Control). The data revealed significantly high frequencies of erythrocytic abnormalities including nuclear as well as cytoplasmic in the fish blood sampled from lake B when compared to those of lake A. Such abnormalities in erythrocytes of fish varied seasonally also with summer exhibiting maximum deformities which can be attributed to the presence of genotoxic pollutants in the selected water bodies. The values were statistically significant at P<0.0001.

Assessment of contamination and health risk of heavy metals in selected water bodies around gold mining areas in Ghana.

Heavy metal contamination of selected rivers in Ghana was studied as part of a bigger project aimed at setting background standard for heavy metals in the Ghanaian environment. Water samples were collected from major mining and eight pristine areas. The samples were acid digested with aqua-regia and analyzed with ICP-MS for As, Cd, Hg, Zn, Cu, Mn, Fe, Cr, Al, V, Co, Ni, and Pb. The average concentrations (mg/L) from the pristine sites ranged from 0.002 ± 0.00(As) to 0.929 ± 0.06 (Fe) and 0.002 ± 0.00 (Pb) to 20.355 ± 5.60 (Fe) from the mining sites. With the exception of Al, Fe, and Mn, the metals level were found to be within the WHO and USEPA guideline limits. Hazard quotients (HQ) for ingestion and dermal contact for pristine and mining samples ranged from 3.00E-04 (Cu) to 0.84 (Cr) and 2.40E-06 (Cu) to 7.44 (As), respectively. The carcinogenic risk (CR) for ingestion and dermal contact ranged from 5.03E-06 to 1.71E-07 (Cr) and 4.22E-08 to 1.44E-09 (Cr), respectively. Arsenic showed a CR value higher than the acceptable limit (1.8E-02) from the mining sites which poses carcinogenic health threat. Multicriteria ranking suggests Birim river (EAM) as the most contaminated. The pattern recognition and multicriteria approach in characterizing the heavy metal contamination (for the first time in the case of Ghana) from the various sites will provide fresh insights into the risk assessment of heavy metals in contaminated surface waters.

Climate variability, water levels, and fish catch in the Upper East Region of Ghana

AbstractThe aim of the research was to investigate the effects of climate variability on selected water bodies in the Upper East Region of Ghana using time series decomposition and simple linear regression analyses. Data on temperature and rainfall (1960–2015), annual total fish catch (1996–2016), and the recorded water levels (1987–2015) of a major reservoir, the Tono, were used. Time series decomposition analyses were performed on the rainfall, temperature, and water level data to identify their trends. While temperature was increasing, rainfall was decreasing and resulted in a decrease in the water level in the Tono Reservoir. The decreasing water level in the reservoir made fish catch easier, which led to overfishing. Out of the other 39 dugouts studied, 8 (21%) were silted. Also, rainfall was decreasing at 4.4% per decade and minimum and maximum temperatures were increasing at 2.5% and 0.03% per decade, respectively. The minimum, maximum, and mean water levels of the Tono Reservoir were 3.7, 8.0, and 4.9 meters (m), respectively. The water level of the Tono Reservoir was decreasing by −0.08 m per year. It is concluded that the water level in the Tono Reservoir was continually decreasing as a result of decreasing rainfall and increasing maximum and minimum temperatures. To maintain a much more stable microclimate and decrease the siltation rate of the reservoirs, farmers are advised to stop farming along the banks of water bodies and avoid clearing vegetation. Fishermen are also encouraged to adopt fish farming in enclosed areas within the reservoir to meet the growing protein demands in the Upper East Region of Ghana.

Antioxidant, biochemical and histologic responses to exposure to selected water bodies within Lagos Mainland, Nigeria

Antioxidant, biochemical and histologic responses to exposure to selected water bodies within Lagos Mainland, Nigeria

Economics of public investment in rehabilitation of water bodies in the saline zone of West Bengal, India

Although surface irrigation through water bodies like tanks still occupies an important place in the irrigation sector in some ecologically fragile regions like saline zones of India, the importance of it has decreased over the years for various reasons. Recognising the importance of surface irrigation for agricultural development, Government of India had taken various irrigation development programmes to improve surface irrigation based on water bodies over years. The present paper attempts to do cost benefit analysis of selected 22 water bodies renovated under two public investment programs namely 'National Project for Repair, Renovation & Restoration (RRR) of Water Bodies directly linked to Agriculture' and 'Rural Infrastructure Development Fund (RIDF)' in the saline zone in West Bengal. The paper finds that out of 22 selected water bodies, public investment on 19 water bodies is economically justifiable. The command area of the water body, fishing in the water body, type of the water body, existence of irrigation equipments, size of the investment are found to have significant positive impact on the net present value (NPV). The issue of salinity is found to be a great challenge in the management of water bodies in the region.

Some Aquatic Macrophytes and their Metal Accumulation Potentiality

The present study analyses the potential capacity of aquatic macrophytes to accumulate heavy metals from contaminated waters of three different aquatic bodies namely Mahil Talab, Sumera Talab and Kothi Talab (lake). Four different macrophytes taken for study due to their abundance, are named as Eichhornia crassipes (Mart.), Hydrilla verticillata (L. F.), Chara spp. (L.) and Lemna minor (L.) Samples for the analysis of heavy metals were collected from these ponds during the period of October 2015 to September 2016. Five heavy metals named as Fe, Cd, Cu, Cr, Pb and Ni were analyzed in water, sediments and selected plant species which were abundant in water. The amount of metals and their accumulation status recorded in the studied macrophytes are arranged in the given sequence Fe>Pb>Cd>Cr>Cu>Ni. On the basis of metal concentration in different aquatic plants, water bodies and sediment, Pb and Cd was found to be target metal for the removal from the selected water bodies. The present experiments were carried out in the laboratory to analyze the Pb and Cd uptake capacity by above mentioned aquatic macrophytes. From the aspect of phytoremediation in present research, out of the four different macrophytes as above E. crassipes and Chara spp. may be considered as more affective for remediation of contaminated water bodies of Bundelkhand region especially for Pb and Cd removal.

Distribution and habitats of &lt;i&gt;Burnupia trapezoidea&lt;/i&gt; (Boettger, 1910) (Gastropoda: Ancylidae) in South Africa

This paper deals with the geographical distribution and habitat preferences of B. trapezoidea , the third most widespread species of the 14 species of Burnupia currently on record in the database of the National Freshwater Snail Collection (NFSC) of South Africa. Although the 121 loci ( 1 / 16 square degrees) from which the 445 samples of B. trapezoidea were collected are much fewer than the number reported for B. capensis , the range of its geographical distribution is almost as widespread as that of B. capensis . The limited distribution of B. trapezoidea in the Limpopo, Northern Cape and Western Cape Provinces can most probably be attributed to the paucity of perennial water bodies in these areas and the fact that Burnupia spp. in general have poor abilities to overcome conditions of desiccation prevalent in these areas. It is therefore not surprising that the majority of samples were collected in perennial rivers and streams. A Random Forest statistical analysis selected water bodies, the presence or absence of marginal and aquatic vegetation, and type of substratum as the most important variables that played a significant role in determining the presence and numbers of specimens of B. trapezoidea in a specific area. In this respect, temperature and turbidity, respectively, played a moderate and minor role. Little is known regarding the conservation status of Burnupia spp, in general, but habitat degradation and climatic warming could be reasons for concern. However, in extensive on-going biodiversity surveys in two rivers and selected tributaries in the North-West Province, many new distribution records of B. trapezoidea are still being created and therefore this species could probably be considered for listing as not endangered. In view of its wide distribution, largely sessile, benthic lifestyle, and ability to bioaccumulate various substances, the feasibility to utilise it as indicator of river ecosystem health in South Africa should be explored. Keywords: Mollusca, Ancylidae, Burnupia trapezoidea , geographical distribution, habitat preferences, conservation status, South Africa

Culturable cyanobacteria from some selected water bodies located in the major climatic zones of Sri Lanka

Cyanobacteria are oxygenic photosynthetic prokaryotes with a wide morphological diversity with some members capable of fixing atmospheric N 2 . This paper reports on the taxa isolated and cultured from water in selected reservoirs in the Dry, Intermediate and Wet zones of Sri Lanka with the potential of utilizing them for biofuel and other industries including cosmetics. Water samples were concentrated by filtering through plankton net and re-suspended in 50 mL of either in respective reservoir water samples or in distilled water. Aliquots of these were cultured in blue green 11 (BG 11) and GO (same as BG11 media but N-free) media. Cultures were maintained under 2,000 lux light intensity with shaking at 200 rpm. A total of 64 cyanobacterial cultures, isolated by repeated sub-culturing in liquid and agar media, were observed under a light microscope for identification. While 16 different taxa were isolated from the Dry Zone, 12 and 5 taxa were isolated from the Wet and Intermediate zones, respectively. The frequency of isolating Oscillatoria sp. was high (10 reservoirs) followed by Microcoleus sp. and Microcystis sp. (each from 6 reservoirs). A strong positive correlation was recorded between cyanobacterial occurrences with abiotic properties such as water temperature, pH and secchi depth (turbidity). Samples prepared in water from respective reservoirs gave faster growth during culturing than those prepared in distilled water. The occurrence, availability and culturability of the isolates obtained in the present study will be useful in the development of value-added cyanobacterial products and cyanobacteria-based industries including biofuel.

Assessment of depth and turbidity with airborne Lidar bathymetry and multiband satellite imagery in shallow water bodies of the Alaskan North Slope

Airborne Lidar bathymetry (ALB) is an effective and a rapidly advancing technology for mapping and characterizing shallow coastal water zones as well as inland fresh-water basins such as rivers and lakes. The ability of light beams to detect and traverse shallow water columns has provided valuable information about unmapped and often poorly understood coastal and inland water bodies of the world.Estimating ALB survey results at varying water clarity and depth conditions is essential for realizing project expectations and preparing budgets accordingly. In remote locations of the world where in situ water clarity measurements are not feasible or possible, using multiband satellite imagery can be an effective tool for estimating and addressing such considerations.For this purpose, we studied and classified reflected electromagnetic energy from selected water bodies acquired by RapidEye sensor and then correlated findings with ALB survey results. This study was focused not on accurately measuring depth from optical bathymetry but rather on using multiband satellite imagery to quickly predict ALB survey results and identify potentially turbid water bodies with limited depth penetration. For this study, we constructed an in-house algorithm to confirm ALB survey findings using bathymetric waveform information.The study findings are expected to contribute to the ongoing understanding of forecasting ALB survey expectations in unknown and varying water conditions, especially in remote and inaccessible parts of the world.

Pesticides distribution in surface waters and sediments of lotic and lentic ecosystems in Agbede wetlands

An investigation on the availability and distribution of Lindane (HCHs) and Total organochlorine phosphate (TOCP) in the surface waters and sediments of selected water bodies in Agbede wetlands was carried out from December, 2012 to May, 2014 in order to cover seasonal trends in both matrixes. A Gas Chromatograph model Hewlett-Packard (HP9) 5890 Series II equipped with 63Ni Electron Capture Detector (ECD) of activity 15 mCi with an auto sampler was employed for the analysis of the water and sediment samples in the laboratory under standard condition. Spatial and temporal variations showed that the concentrations of TOCP closely followed that of Lindane in surface water and was a replica in the sediment matrix. Meanwhile, the values obtained for Lindane and TOCP in the sediment were slightly higher than (about 3 folds) that in the surface waters. The concentrations of pesticides in the surface waters and sediments of lotic and lentic ecosystems in Agbede wetlands were found to be far below the set limit of 0.01μgL-1 by the Federal Ministry of Environment of Nigeria (FMEnv) and World Health Organisation (WHO) respectively. The low values recorded in this study suggested seldom application of pesticides particularly on a subsistence form and therefore not indicative of possibility of any serious health issues.Key Words: Below Detection Limit, Concentrations, Ecological Zone, Lindane

Benthos Composition and Abundance in Lentic Ecosystems

The Benthic invertebrates such as nymphs of stonefly, mayfly, caddisfly larvae, snails, mussels, crustaceans, rat-tailed maggot, etc., convert and transport nutrients from one part of the water body to another, influencing nutrient cycling. In the present study, phytobenthos comprised of three major groups namely Bacillariophyceae, Chlorophyceae, Myxophyceae, whereas zoobenthos comprised of eleven major groups namely Protozoa, Rotifera Cladocera, Ostracoda, Coleoptera, Diptera, Ephemeroptera, Hemiptera, Trichoptera, Gastropoda and Odonata. The study revealed that zoobenthos were more dominant than phytobenthos. Among zoobenthos, Dipterans were found to be abundant followed by Cladocerans and least were Trichopterans, whereas among phytobenthos Bacillariophyceae was found to be most dominant followed by Chlorophyceae and Myxophyceae. The negative but significant correlation between zoobenthos and phytobenthos in all selected water bodies during study indicated grazing of former on latter proving top down control in these lentic ecosystem.

A study on aquatic insect diversity on some selected water bodies in Guwahati, Kamrup district, Assam

The present study has generated qualitative and quantitative data of insects from selected habitats of Guwahati, Assam which were then assessed at the family level. Abundance and diversity of aquatic insects was studied in five water bodies, (four ponds and a beel) of Guwahati during 2013 to 2014 and insects belonging to 26 genera, under 17families and 5 orders were recorded. From this study, it was observed that the most abundant order in all the water bodies is the order Ephemeroptera, followed by Odonata, Hemiptera and Diptera. During the study period abundance of insects was comparatively higher inDighalipukhuri.

Fifteen-year monitoring of the turbidity dynamics in large lakes and reservoirs in the middle and lower basin of the Yangtze River, China

The Middle and Lower Yangtze River (MLY) basin holds the most freshwater in East Asia; however, the conditions of basin-scale water turbidity remain unknown. In this work, a remote sensing algorithm was developed to estimate the concentrations of the total suspended sediments (TSS) in large lakes and reservoirs over the MLY basin and was based on a band ratio between 555nm and 645nm of the atmospherically corrected surface reflectance of the Moderate Resolution Imaging Spectroradiometer (MODIS). In situ samples used to calibrate the algorithm were collected from 58 lakes and reservoirs with a TSS range of 1 to 300mgL−1, and the uncertainty of this algorithm was 30–40%. The algorithm was subsequently applied to a total of 102 lakes and reservoirs located in the MLY basin to derive TSS maps from 2000 to 2014 at a 250m spatial resolution, and the first comprehensive document of the TSS distributions and dynamics of large inland waters of the MLY basin was created. The seasonal patterns among the selected water bodies were similar, with the largest TSS concentrations occurring in the first and fourth quarters in a year and the lowest values occurring in the third quarter. In contrast, spatial heterogeneities were revealed by the 15-year long-term mean TSS climatology information. Although most lakes downstream of Poyang Lake were turbid with 15-year TSS climatology values of 45–100mgL−1, waters between Poyang and Doting Lake were relatively clearer with TSS climatology values of 15–45mgL−1, and the clearest waters (<15mgL−1) were found in reservoirs. The turbidity of 64.5% (e.g., 49/76) for lakes in Class II exhibited a decreasing trend over the 15-year period, and the Three Gorges Reservoir (TGR) and Dongting Lake in Class I also showed significant TSS declines. Analysis with meteorological data shows that the intra-annual variations appear to be significantly correlated with local precipitation, with a time lag of two months for TSS. The prominent TSS decreasing trend of the lakes in Class II was probably linked to the significant NDVI increase in the MLY basin, whereas the TSS decrease in the TGR and Dongting Lake is likely to be attributed to the impoundment of the Three Gorges Dam. The TSS environmental data record (EDR) of large inland waters presented in this study serves as an important reference for future water quality monitoring and evaluation in the MLY and in China.

Deterioration and Degradation of Aquatic Systems Due to Brick Kiln Industries – A Study in Cachar District, Assam.

Brick industries are unorganised, rural, small scale industries in Cachar district of Assam which play an important role in economic development of the entire region. It has been observed during the study that these brick industries are responsible for large scale environmental problems like land degradation, air pollution, water quality degradation and loss of biodiversity. The present study deals with the quality of water in the selected brick kilns in Cachar district and its degradation during Jan-Dec 2014. The existing water bodies are contaminated with different compounds and continuous siltation from the brick kilns. The research focuses on the variation of various physico-chemical parameters such as water temperature, pH, conductivity, Total alkalinity, Dissolved oxygen, Carbondioxide, Nitrate, Phosphate, Transparency in the selected water bodies. The studied ponds were found to be in degrading state with less productivity. Moreover, the result obtained showed the need and urgency to restore the physical, chemical and biological management tactics to conserve and preserve the ecological imbalance and disturbance in the hydro-geo-chemical and hydro-biological cycles that adversely affect the food chain and food web in the brick kiln affected aquatic bodies.