Zooplankton diversity and physico-chemical conditions in three perennial ponds of Virudhunagar district, Tamilnadu

Plankton diversity and physico-chemical parameters are an important criterion for evaluating the suitability of water for irrigation and drinking purposes. In this study we tried to assess the zooplankton species richness, diversity and evenness and to predict the state of three perennial ponds according to physico-chemical parameters. A total of 47 taxa were recorded: 24 rotifers, 9 copepods, 8 cladocerans, 4 ostracods and 2 protozoans. More number of zooplankton species were recorded in Chinnapperkovil pond (47 species) followed by Nallanchettipatti (39 species) and Kadabamkulam pond (24 species). Among the rotifers, Branchionus sp. is abundant. Diaphanosoma sp. predominant among the cladocerans. Among copepods, numerical superiority was found in the case of Mesocyclopes sp. Cypris sp. repeated abundance among ostracoda. Present study revealed that zooplankton species richness (R1 and R2) was comparatively higher (R1: 4.39; R2: 2.13) in Chinnapperkovil pond. The species diversity was higher in the Chinnapperkovil pond (H': 2.53; N1: 15.05; N2: 15.75) as compared to other ponds. The water samples were analyzed for temperature, pH, electrical conductivity alkalinity salinity, phosphate, hardness, dissolved oxygen and biological oxygen demand. Higher value of physico-chemical parameters and zooplankton diversity were recorded in Chinnapperkovil pond as compared to other ponds. The zooplankton population shows positive significant correlation with physico-chemical parameters like, temperature, alkalinity phosphate, hardness and biological oxygen demand, whereas negatively correlated with rainfall and salinity. The study revealed that the presence of certain species like, Monostyla sp., Keratella sp., Lapadella sp., Leydigia sp., Moinodaphnia sp., Diaptomus sp., Diaphanosoma sp., Mesocyclopes sp., Cypris sp. and Brachionus sp. is considered to be biological indicator for eutrophication.     

南京东郊蔬菜种植基地地表水氮、磷、重金属含量及影响因素

南京东郊典型蔬菜基地地表水环境质量的调查分析表明:(1)在当前的生产和生活条件下,地表水尚未受Pb、Cu、Zn、Cd和Cr污染,但有不同程度的氮、磷污染。(2)河流氮、磷污染比池塘严重。河流水中氨氮和水溶性磷的比例相对较高,而池塘水中硝态氮、有机氮和有机磷的比例相对较高,这种差别有助于识别地表水中氮、磷的来源。河流底泥中总氮、总磷和重金属含量(Cr除外)比塘泥高,表明河水氮、磷及重金属污染风险比池塘水高。(3)南京东郊蔬菜基地地表水中氮、磷及重金属主要来自城市生活污水的排放,其次来自蔬菜栽培中有机肥过量投入造成的流失。因此,保护城郊地表水应从城市生活污水净化和蔬菜栽培中有机肥的合理施用入手。     

人工湿地循环处理的养殖水体中浮游动物动态变化

2004年3月～11月对人工湿地循环处理的养殖水体中浮游动物的动态变化进行了研究,探讨不同的处理方式和放养类型对水体中浮游动物的影响及生物多样性指数的变化.结果表明,养殖水体经人工湿地处理后,水质改善,对浮游动物去除率在60%以上,几乎没有影响到浮游动物的群落结构,循环水量最大的1号塘浮游甲壳动物隆腺溞占优势,密度较其他塘低,而生物量则高;放养类型相同的循环塘3号塘和静态塘4号塘,浮游动物种类基本相同,但种类数3号塘明显多于4号塘;辛普森多样性指数显示:1号塘>2号塘>3号塘>4号塘,说明循环塘水质好于静态塘.图4表5参21     

Biodiversity of algae and protozoa in a natural waste stabilization pond: a field study

A field study was carried out on the biodiversity of protozoa and algae from a natural waste stabilization pond during November, 1996 to April, 1997. The raw waste and pond samples were analysed for physico-chemical and biological parameters. High dissolved oxygen (DO) coinciding with phytoplankton peak was recorded. The algae--Chlorella vulgaris, Scenedesmus acuminatus, Oscillatoria brevis and Nostoc piscinale and Protozoa--Paramecium caudatum, Acanthamoeba sp., Bodo saltans and Oikomonas termo were obvious as dominant species, whereas algae Ochromonas pyriformis and Synura uvella and protozoa, Didinium masutum and Stentor coerulus were noted as rare species. Totally 71 species of algae and 13 species of protozoa were identified.     

Impact of mineral deposition on shrimp, Penaeus monodon in a high alkaline water

This study compares water quality parameters, shrimp growth and mortality rates, and biomass at harvest in two ponds of equal size, seeded with the same density (7 m2) of White Spot Syndrome Virus (WSSV) and Monodon Baculo Virus (MBV) negative post-larvae (PL)-20 of shrimp, Penaeus monodon in the Vellar estuary of South India. The primary difference between the ponds was the water source; one was filled from the estuary and the second with water from bore wells with high alkalinity. Temperature in both ponds was similar and reached 320C after 185 days of culture. Dissolved oxygen (DO) levels were within the acceptable range although levels in the alkaline pond were near the lower limit for the last 90 days before harvest. Salinity levels were similar in both ponds, above optimal levels, and increased over the 185 days. Alkalinity in the estuarine water was typically <50 ppm and again 200-320 ppm in the alkaline pond. In the alkaline pond, beginning on the 75th day mineral deposits was observed covering all parts of the shrimp including the eye and the inner gill chambers, and by harvest, 42% of the shrimp showed this coating. Elemental analysis identified the major constituents as calcium, phosphorus and manganese. Survival rates in the estuarine-water-fed pond was 92% with a total pond biomass at harvest of 1.65 tons ha-1 compared to survival of 79% in the alkaline pond and a biomass at harvest of 1.020 tons ha-1. When well water must be used, its alkalinity should be monitored and diluted with water from other sources.     

Physico-chemical characteristics of the Vellar estuary in relation to shrimp farming

All the physico-chemical parameters such as temperature, LEC, salinity, pH, dissolved oxygen and nutrients like total phosphorus, inorganic phosphate, nitrite and silicate studied in relation to shrimp farming. There are as many as 42 shrimp farms situated on the banks of Vellar estuary. These farms discharge the used water into the estuary, which may influence the biota there. In the present study the physico-chemical feature in relation to shrimp farming were studied in 3 stations of the estuary. When compared with the previous data from Vellar estuary there was no much difference in physico-chemical characteristics due to shrimp farming.     

Role of probiotics on the environment of shrimp pond

Recent disease outbreak in shrimp farming caused mainly by bacteria, virus, fungi or a combination of these etiologic agents is attributed to disturbance in the environment of pond. To combat this, different antibiotics and chemicals are being used which are reported to be not environment friendly. Of late, a new and unique biotechnological product called "Probiotics " is being used widely by all the shrimp farmers worldwide, which is found to be more effective and environmentally safe also. In the present study 2 probiotics were used in a small 0.7 ha shrimp farm near Pattukottai in Tamil Nadu State for one culture period for the management of pond environment and also the gut ecology of Penaeus monodon. The environmental parameters analysed were within the acceptable limits. It was evident from the results that the production was better in the experimental pond where the probiotics were used. The biological parameters such as the average body weight, FCR and total harvest achieved were better in the experimental pond than the control pond, all due to congenial environment, which obtained in the former mainly due to the use of probiotics.     

铬在稳定塘系统中的迁移分布和归宿

含铬污水进入混合较好的稳定塘系统时,铬在其中累积,其累积规律可用如下数学模式描述: 稳定塘系统能较好地去除污水中的铬。被去除的铬主要转入塘底沉积物中。塘中放养凤眼莲能提高除铬效果,因为放养凤眼莲能使铬更充分有效地沉降。能否充分地运用有利于悬浮微粒聚结沉降的技术和措施,是设计除铬或类似重金属稳定塘系统成功与否的关键之一。     

Complex dynamics of toxin producing algal species and primary productivity in two water ponds of Faizabad

In order to develop a method of predicting and assessing pond eutrophication, which is a serious environmental problem, and to propose effective measure of improvement of water quality. The present study was performed to measure water quality variables, primary productivity, chl-a and biomass of toxin producing algal species and fish production. High nutrient influx and toxin producing algal species have been observed during June 1999 to May 2000 in two water bodies [Girija Kund (A) and Maqubara pond (B)] of Faizabad. The maximum chl-a concentration, toxins producing algal species biomass were found to be 415.00 and 515.00 in pond A, while 451.00 microg/l and 541.22 mg/l in pond B, respectively in the case of Microcystis aeruginosa. Ecological parameters to evaluate GPP, NPP and CR were found to be 297.00, 134.000 and 182.00 mgCm3/h in summer season in pond B, respectively which is higher than pond A. A poor association existed between chl-a and GPP. Temporal variation (Photosynthetic rate) in A(max) & P(max) was also observed to evaluate the productivity of pond. Annual fish production potential of the ponds A and B has been estimated to be around 342.00 Kg and 204. 00 Kg, respectively which may be due to the presence of toxin producing algal species.     

Effects of Pond Draining on Biodiversity and Water Quality of Farm Ponds

Farm ponds have high conservation value because they contribute significantly to regional biodiversity and ecosystem services. In Japan pond draining is a traditional management method that is widely believed to improve water quality and eradicate invasive fish. In addition, fishing by means of pond draining has significant cultural value for local people, serving as a social event. However, there is a widespread belief that pond draining reduces freshwater biodiversity through the extirpation of aquatic animals, but scientific evaluation of the effectiveness of pond draining is lacking. We conducted a large‐scale field study to evaluate the effects of pond draining on invasive animal control, water quality, and aquatic biodiversity relative to different pond‐management practices, pond physicochemistry, and surrounding land use. The results of boosted regression‐tree models and analyses of similarity showed that pond draining had little effect on invasive fish control, water quality, or aquatic biodiversity. Draining even facilitated the colonization of farm ponds by invasive red swamp crayfish (Procambarus clarkii), which in turn may have detrimental effects on the biodiversity and water quality of farm ponds. Our results highlight the need for reconsidering current pond management and developing management plans with respect to multifunctionality of such ponds. Efectos del Drenado de Estanques sobre la Biodiversidad y la Calidad del Agua en Estanques de Cultivo     

Study of zooplankton emergence pattern and resting egg diversity of recently dried waterbodies in North Maharashtra Region

Seasonal patterns of temperature, pH, conductivity dissolved oxygen, phosphate and sulphate have been studied on the basis of physico-chemical characteristics of pond ecosystem. Importance of soil egg banks and their contribution to the diversity in freshwater ecosystem has been studied. We have focussed our attention on soil egg bank diversity and zooplankton emergence patterns of some recently dried aquatic habitats, comparing to that of neighbouring temporary pools with the permanent ponds. The emergence pattern from the soil egg bank followed an orderly succession from Protists-Rotifers and Crustaceans have been investigated. Dominant Protists emerged from the egg bank were Lacrymaria within rotifers. They were the first to emerge followed by Hexarthra blooms. The diversity of zooplankton in permanent ponds was significantly higher (i.e., 19) than the diversity in the ephemeral pools (i.e., 08). However; the zooplankton abundance in the ephemeral pools was higher with more than an order of magnitude, than that in ponds. Interestingly the number of species recorded in the egg bank was more than those present in the water columns of the pools. We have recorded 08 species of rotifera i.e. Lecane sp L curvicornis, L. bulla, K. quadrata, B. patulus, B. rubens, Branchionus calyciflorus, Testudinella sp which were not present in the neighboring permanent or ephemeral waterbodies during that period. Unequivocally suggest that in order to understand the zooplankton biodiversity; it is also important to evaluate the diversity of egg bank present in the sediment. A total 19 species were recorded including Copepoda 06 sp, Cladocera 05 sp and Rotifera 08 sp.     

克螨特和霸螨灵及其混剂在水中的光降解

研究了克螨特、霸螨灵在几种水体中的光降解以及 2种农药之间的光敏化或光猝灭效应。结果表明 ,在 3 0 0W高压汞灯光照处理时 (试验试管距光源 8cm) ,克螨特和霸螨灵都极易降解 ,克螨特的光解半衰期为 9.0 6min ,霸螨灵的光解半衰期仅为 1 .4 8min。克螨特在不同水体中的光解率为 :重蒸馏水 >鱼塘水 >河水 >井水 ,霸螨灵的光解率为 :井水 >重蒸馏水 >鱼塘水 >河水 ;2种农药在现采水、过滤水、灭菌水中的光解率依次降低。克螨特和霸螨灵混剂在重蒸馏水中互为光猝灭剂 ,在井水、河水和塘水中霸螨灵对克螨特有极显著的光敏化作用 ,而克螨特对霸螨灵有极显著的光猝灭效应。克螨特、霸螨灵在pH 5和 pH 9缓冲液中光解率比之在 pH 7缓冲液中稍快 ,光猝灭效应也较强烈。在重蒸馏水中太阳光照处理时 ,克螨特和霸螨灵互为光敏剂 ,而高压汞灯下则互为光猝灭剂。     

Impact of domestic sewage on fresh water body

In the present study various (physico-chemical) factors were assessed over a period of two years (from February 2002 to January 2004) to note the chemistry and quality of tank water in Bhalki town of Bidar. Physico-chemical factors like pH, dissolved oxygen, magnesium, chlorine, nitrite, sulphates and chemical oxygen demand were found with maximum concentration during summer season. Similarly, during monsoon season free carbon dioxide, alkalinity hardness, calcium, phosphate, silicon, total solids and biological oxygen demand; and in winter season organic matter were recorded. The concentrations viz., pH, hardness and nitrite were more compared to the potable water standard of WHO. The correlation matrix and dendrogram of physico-chemical factors have been computed and analysed. The positive co-relation coefficient observed between pH and magnesium, dissolved oxygen and hardness, free carbondioxide and calcium, alkalinity and nitrite, alkalinityand phosphate, alkalinity and biological oxygen demand, hardness and calcium, hardness and magnesium, magnesium and chlorine, nitrate and phosphate, nitrite and biological oxygen demand, phosphate and organic matter; and silicon and chemical oxygen demand. The dendrogram confirms chlorine, pH, hardness, silicon, total solids and sulphates are the key factors of the change in the chemistry of water body     

Limnological investigations of Texi Temple pond in district Etawah (U.P.)

Present investigations were carried out on the limnological aspects of Texi temple pond in district Etawah. Many of the parameters were found below the permissible limits for drinking water as suggested by WHO. A total of 18 parameters were analysed and their seasonal variations in the year 2003 were discussed.     

Limnology of Kharland (saline) ponds of Ratnagiri, Maharashtra in relation to prawn culture potential

The coastal saline soils, Kharlands, have great potential for their use in aquaculture. This study has been taken up to understand the limnology of the ponds in Kharland area for assessing their prawn culture potential. This study was carried out during September, 1999 to August, 2001. Each Kharland pond has an area of 0.045 hectare. During the study, depth of pond water was 47.7 to 120.0 cm, temperature varied from 25.7 to 34.5 degrees C; transparency from nil to 65.0 cm; specific conductivity from 1.78 to 94.5 microS.cm(-1); total dissolved solids from 0.89 to 27.55 ppt; pH 5.42 to 8.25; dissolved oxygen 1.6 to 8 mg.l(-1); free carbon dioxide 10.00 to 44.00 mg.l(-1); total alkalinity 5.00 to 142.00 mg.l(-1); salinity 0.45 to 39.55 ppt; total hardness 245.00 to 5945.00; calcium 56.05 to 1827.6; magnesium 110.74 to 4507.75 mg.l(-1); dissolved organic matter 1.45 to 9.68 mg.l(-1); ammonia 1.00-8.00 microg.l(-1); nitrite nil to 20.00 micro l(-1) and nitrate 7.5 to 17.5 microg.l(-1). These Kharland ponds are unique in physio-chemical characteristics during their seasonal cycle. From July to October, these ponds have nearly freshwater while from November to May pond water becomes saline. Thus, there is a great possibility of taking up monoculture of both the freshwater and brackish water prawns as well as polyculture of prawns and fishes in the Kharland ponds.     

Chemometric studies of water quality parameters of Sankarankovil block of Tirunelveli, Tamilnadu

The fluoride concentration in ground water was determined in Sankarankovil block of Tirunelveli district of Tamilnadu (India) where it is the only source of drinking water. Various other water quality parameters such as pH, electrical conductivity total hardness and total alkalinity as well as calcium, magnesium, carbonate, bicarbonate and chloride concentrations were also measured. A systematic calculation of correlation coefficient among different physico-chemical parameters was performed. The analytical results indicated considerable variations among the analyzed samples with respect to their chemical composition. Majority of the samples do not comply with Indian as well as WHO water quality standards. The fluoride concentration in the ground water of these villages varied from 0.66 to 3.84 mg l(-1), causes dental fluorosis among people especially children of these villages. The high and low fluoride containing areas were located using isopleth mapping technique. Overall water quality was found unsatisfactory for drinking purposes without any prior treatment except at few locations out of 50 villages.     

Bacteriological analysis of a pond water from Gobardanga,West Bengal

The present communication deals with the bacteriological examination of a pond water, which is being used as one of the sources of drinking water, by multiple tube fermentation test to detect the coliform bacteria. The test was performed sequentially in three stages: presumptive, confirmed and completed coliform test. The results show that as the most probable number (MPN) index per 100 ml is 23, that pond water should be treated as nonpotable.     

Assessment of phytoplankton density in relation to environmental variables in Gopalaswamy pond at Chitradurga, Karnataka

Surface water samples of the Gopalaswamy pond were studied at two different sites during September 1997 to January 1998 and phytoplanktons were studied in relation to ten environmental variables during this period. A total of 30 species of phytoplanktons were identified under four classes, Chlorophyceae, Cyanophyceae, Bacillariophyceae and Euglenophyceae. Among these, maximum density was recorded under Cyanophyceae, Chlorophyceae, Cyanophyceae and Bacillariophyceae showed considerable fluctuations with environmental variables.     

Fresh water blue green algae from three agro-climatic zones of Uttar Pradesh, India: distribution pattern with seasonal variation

The paper deals with 45 species of 21 genera of fresh water blue green algae (BGA) from three different agro-climatic zones of Uttar Pradesh. Samples were collected from different habitats varying in physico-chemical properties. Out of 45 species, 13 species belonged to order Chroococcales, 31 to order Nostocales, while only 1 species belonged to order Stigonimatales i.e. Fischerella mucicola. The physico-chemical parameters like pH, temperature, dissolved oxygen, electrical conductivity, nitrate, nitrite and rainfall play an important role in the periodicity of BGA. A positive correlation was found between dissolved oxygen (DO) of different ponds and species diversity, except in the case of western region of Uttar Pradesh (Farukhabad and Mahoba districts) where a positive correlation was found in electrical conductivity and total dissolved solids.     

喀斯特小流域复杂景观中水质状况

以红枫湖流域周边一个受人为活动严重影响的农田源头溪流-王家寨小流域为研究对象,设置11个监测点研究硝酸盐（NO3-N）、氨态氮（NH4＋-N）、溶解性无机磷（PO4--P）、总磷（TP）和总悬浮物（TSS）在复杂景观中的变化状况。降雨后采样水中氮、磷含量明显低于雨后的地表积水,地表积水受各种影响,水质降低。水塘型湿地,其丰水期的PO43--P、TP、SS高于枯水期,与水循环条件较好的流水溪流还是存在明显的区别。从平均值来看,枯水期地表水和地下水TP都超过5级水质标准。水质与＂源＂景观的关系不明显,说明喀斯特小流域中复杂的景观结构对氮磷的截留作用。