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Background Macrophytes (fresh water plants) comprise a diverse group of the flora which play important roles in the maintenance of trophic food chains and biogeochemical processes, but are deleterious when present in excess. However, due to various anthropogenic activities, there is accumulation of nutrients in aquatic ecosystems resulting in massive macrophytic growth. These weeds do not possess any economic value and remain laid on lake shores after harvesting and become a source of odor problem, thus posing a challenge to the lake management authorities regarding their proper disposal. However, vermicomposting turns these macrophytes into materials useful in horticulture/agriculture for restoration of soil fertility, in addition to providing a solution to the nuisance of harvested weeds. Results The study was conducted to investigate the effect of different rates (2, 4 and 6 t/ha) of macrophyte-based vermicompost on germination, growth and yield of Solanum melongena under field conditions. The data revealed that different rates of vermicompost produced varied and significant effect (P \ 0.05) as compared to the control on germination, growth and yield parameters with maximum value recorded at 6 t/ha, followed by 4 t/ha and the least at 2 t/ha. The dose of 6 t/ha significantly (P \ 0.05) increased germination (22.56 ± 2.5 %), number of fruits per plant (3.55 ± 0.07) mean fruit weight (73 ± 5.0 g), yield per plant (1.48 ± 0.05 kg) and marketable fruits (28.66 ± 3.0 %) when compared with the control. The study suggests that macrophyte-based vermicompost as a potential source of plant nutrients for sustainable crop production. Conclusion Macrophyte-based vermicompost is an efficient quality yielder and economy enhancer for sustainable agriculture especially for the communities having vegetable gardens around lakes will benefit by using macrophyte vermicompost, a balanced and low-cost organic fertilizer.

The present study was carried out to evaluate the performance of 16.1 MLD sewage treatment plant (STP) located at Brari Nambal (J&K), India. The STP is based on sequential batch reactor (SBR) technology. Wastewater (influent and effluent) samples were analyzed for 14 different physicochemical parameters. Significant variation (P < 0.05) was recorded within and among the wastewaters in pH (

Seasonal variation in surface water quality of Dal Lake was assessed using multivariate statistical techniques. Water quality data collected from 4 sampling sites during 4 seasons was analysed for 13 parameters. Significant variation (p<0.05) in temperature, pH, EC, Ca, Mg, Na, K, DO, BOD 5 , COD, PO 4 -P, NH 4 -N and NO 3 -N of sampling sites during different seasons was observed. Cluster analysis grouped 4 sampling sites during 4 seasons into three clusters of similar water quality as relatively less polluted (LP), medium polluted (MP) and highly polluted (HP) sites. The principal component analysis/factor analysis applied to extract and recognize the factors responsible for water quality variations in four seasons of the year resulted in three principal components for each season accounting for 75.78%, 83.25%, 87.33% and 78.96% of total variance for winter, spring, summer and autumn seasons respectively. Parameters like NH 4 -N, NO 3 -N, BOD 5 and COD have strong positive loading whereas temperature and dissolved oxygen has strong negative loading. Thus, from the principal component/factor analysis it is clear that the domestic wastewaters, agricultural runoff and catchment geology play significant role in water quality variations in the Dal Lake for all the four seasons.

In the present study, potential of Eisenia fetida to recycle the different types of fresh water weeds (macrophytes) used as substrate in different reactors (Azolla pinnata reactor, Trapa natans reactor, Ceratophyllum demersum reactor, free-floating macrophytes mixture reactor, and submerged macrophytes mixture reactor) during 2 months experiment is investigated. E. fetida showed significant variation in number and weight among the reactors and during the different fortnights (P <0.05) with maximum in A. pinnata reactor (number 343.3 ± 10.23 %; weight 98.62 ± 4.23 % ) and minimum in submerged macrophytes mixture reactor (number 105 ± 5.77 %; weight 41.07 ± 3.97 % ). ANOVA showed significant variation in cocoon production (F4 = 15.67, P <0.05) and mean body weight (F4 = 13.49, P <0.05) among different reactors whereas growth rate (F3 = 23.62, P <0.05) and relative growth rate (F3 = 4.91, P <0.05) exhibited significant variation during different fortnights. Reactors showed significant variation (P <0.05) in pH, Electrical conductivity (EC), Organic carbon (OC), Organic nitrogen (ON), and C/N ratio during different fortnights with increase in pH, EC, N, and K whereas decrease in OC and C/N ratio. Hierarchical cluster analysis grouped five substrates (weeds) into three clusters-poor vermicompost substrates, moderate vermicompost substrate, and excellent vermicompost substrate. Two principal components (PCs) have been identified by factor analysis with a cumulative variance of 90.43 %. PC1 accounts for 47.17 % of the total variance represents "reproduction factor" and PC2 explaining 43.26 % variance representing "growth factor." Thus, the nature of macrophyte affects the growth and reproduction pattern of E. fetida among the different reactors, further the addition of A. pinnata in other macrophytes reactors can improve their recycling by E. fetida.

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Aquatic plants play an important role in ecosystem functioning and services but they can also be deleterious if present in excess. The different anthropogenic activities result in accumulation of nutrients in aquatic ecosystems leads to eutrophication with massive weed growth and associated diverse adverse effects. Effective control/management of weeds in different aquatic systems is not only difficult but of short duration. The commonly used methods to manage/control the aquatic weeds are biological, chemical and mechanical, in addition to habitat manipulation. However, these methods can be highly disruptive causing adverse environmental effects and are relatively inefficient. On the other hand different species of earthworms can feed on wide range of weeds and convert them into stable product called vermicompost, rich in plant nutrients. Among different aquatic weeds the most extensively vermicomposted weed is water hyacinth (Eichhornia crassipes (Mart.) Solms), using different earthworm species. Among different earthworm species used for vermicomposting of aquatic weeds, Eisenia fetida (Savigny) is the most commonly used species. Vermicomposting is an efficient ecobiotechnological process that converts the aquatic weeds into nutrient rich material that can acts as suitable plant growth media for sustainable agroecosystems. Further large scale utilization of aquatic weed based vermicompost in horticulture can solve their management and disposal issues along with restoration of organic matter and nutrient depletion at low input basis.

The present work was carried out to study the air quality of Srinagar city and the samples were collected from five different sites which includes commercial area (site-I), industrial area (site-II), residential area (site-III), ecologically sensitive site (site-IV) and sensitive area (site-V). During the study samples were taken on monthly basis and were analyzed for nitrogen dioxide (NO2), sulphur dioxide (SO2) and repairable particulate matter (PM10). Significant variation was recordedwithin and among the sites in NO2 (F3 = 3.82; F4 = 115, P < 0.05), whereas among the sites in SO2 and PM10 (F4 = 167, P < 0.05) and (F4 = 72.55, P < 0.05) respectively. The study revealed higher concentration of NO2 at Lal chowk which is commercial area and vehicular emission could be the one of the reason for higher value of NO2. SO2 exhibited high concentration at industrial area and could be attributed to burning of fossil fuels in industries and use of generator sets. PM10 was also found higher in industrial area due to presence of cement industries in addition to burning of coal as fuel. The overall concentration of NO2 and SO2 were found within the permissible limits for all sites as per National Ambient Air Quality Standards (NAAQS) except for PM10 at site-I and site II. The overall air quality index of site-I and site-II falls within “Moderate” category and for site-III, IV and V falls within “Good” category.