Two groups of 4-6 cells are observed on the dorsal side of pars intercerebralis medialis part of protocerebrum. These cells are designated as median neurosectetory cells (MNSC). The axons of median neurosecretory cells of locus 1 form the median neurosecretory pathway and nervi corporis cardiaci interni (NCCI).The NCCI of two sides decussate each other in the anterior dorsal median part of the protocerebrum, comes out from the brain and enter the aorta wall. The median neurosecretory pathways can be differentiated into two parts viz. the very short prechiasmatic and the long postchiasmatic portions in copulating female Spilostethus pandurus, a heteropteran insect of economic importance.
The negative effect of metals in terrestrial ecosystems has been shown so far little decomposition process and some soil-dwelling invertebrates. Organisms inhabiting contaminated areas can be stressed by metal exposure for a prolonged time and are possibly subjected to selection for increased resistance to metals. This may result in physiological or behavioural adaptations to long term sub-lethal metal exposure. The aim of the present study is to determine effects of prolonged metal contamination on population parameters, especially reproduction, in the forest living ground beetle, Pterostichus oblongopunctatus F. from five study sites with different metal pollution. The observed decrease in the reproductive rate in carabids originating form highly contaminated areas seems to support the hypothesis of a trade-off between efficient decontamination and productivity
The present study is conducted to find out the changes in the feeding habits of springtails, related to their ecological habitat. In this study the results and the observations are compared of the diet of Collembola in three different ecological system viz. (1) tropical forest in Topchachi, Dhanbad. (2) two crop fields in Bhuda, Dhanbad and (3) the epiphytic plant, Tillandsia violacea from a temperate forest in Panchet Dam, Dhanbad. Specimens collected from the crop fields have vegetable matter and fungal conidia in their gut contents. The species associated with the epiphytic plants, showed a distinct type of feeding. In such species, the debris of algae, diatoms and bacteria were found. During the dry season, there were fragments of Prostigmata and Astigmata(Acaridae), mites in the gut of Ptenothrix marmorata .In Seirapurpurea, both in rainy season and dry season, there were fragments of exuvia of springtails and also some parasitic nematodes. The presence of mites in the digestive tract of Collembola from the epiphytic bromeliads could probably be explained by the fact that during the dry season, the populations of Astigmata and Prostigmata are enormous and constitute prey for the spring tails. It is also probable that their ingestion is accidental, or even that they are forced to diversify their diet when the conditions of the ecological niche change.
In the Maithan dam, the Zooplanktons were represented by the Crustaceae( Cladocera, Copepoda and Ostracoda ), Rotifera& Protozoa. The Rotifera is the dominating group followed by Copepoda and then Cladocera. The invertebrates which live on, in or near the substratum of the dam water include representatives of almost every taxonomical group that occurs in fresh water. Rotifera was the abundant group representing 62% of total species, followed by Copepoda 28% and Cladocera 8%. The dominant Zooplanktons recorded in the dam were Filinia sp., Branchionus sp., Asplanchna sp. Abundance of these species indicates that the dam has become eutrophic.
The terrestrial insects are exposed to extreme variations in temperature and moisture than their counterparts in the aquatic ecosystem. The Beetles have certain requirements having specific physiological significance. Being cold blooded, two main characteristics of their population viz. death rate and birth rate are very much dependent on the physico-chemical factors of the soil. Beetle infestations have increased in magnitude and severity as a result of warming temperatures.
This papers deals with oxygen uptake capacity of gills in relation to body weight in a hill stream fish, Garra gotyla (Gray). It was found that oxygen consumption (VO2) increases with the increase in body weight while V02/g/h decreases with the increase in body weight of the fish. The details have been discussed in this paper.
Biodiversity of aquatic insect and physico-chemical water quality parameters in the Bekarbandh pond was assessed during June 2016 to May 2017. Seven sampling stations, each 100m long were established. Three replicates of samplings by aquatic D frame net were used at sampling sites. A total of 4,257 individual of aquatic insect were collected during one year. 6 orders & 12 families were recorded in this study. The family Hydropsychidae and Chironomidae were the most abundant of aquatic insects that was found in the pond water. The CCA revealed the family Mesoveliidae and Chironomidae were correlated with alkalinity in the pond water, whereas dissolved oxygen was correlated with family Baetidae, Coenagrionidae, Hydrophilidae and Helotrephidae. Signs of increasing water quality deterioration were evident in the result of the physico-chemical analyses.
The diversity of insect fauna of two fresh water ponds of Dhanbad was represented by 60 species classified under 15 families and 9 orders.Among the insects collected from the freshwater pond,the order Coleoptera was diverse in number of genera(22).The order Ephemeroptera is represented in BekarbandhTalab by the families Baetidae and Caenidae, which are considered as an indicator of water quality.of the 15metrices selected,taxa richness ,composition measures, tolerance and intolerance and Functional groups were also found out for both two study stations.In the present study, the percentage of Ephemeroptera ,Plecoptera and Trichoptera taxa richness and diversity remained high in station 1,Bekarbandh Talab and reduced drastically in station 2. PampooTalab.Pollution tolerant taxa such as Chironomidae,Tabanidae, Culicidae and Anophilinae were abundant in station 2 i.e PampooTalab. The result of the study reveals great diversity of aquatic insects in freshwater bodies of Dhanbad and suggest the possibility of using insects effectively for biomonitoring programmes.
The Physico-chemical analysis of water is very important for public health studies .Physico-chemical parameters refer to the water quality of fresh water. In the present study two ponds were selected namely Bekarbandh pond and Pampoo pond. Both the ponds are used by local peoples for bathing and even washing clothes .Limnological features of two ponds were taken into account in the present study.The key water quality parameters for fresh water bodies are temperature,oxygen,pH,alkalinity,hardness etc. Due to the several factors within the pond ,these parameters fluctuate daily depending upon photosynthesis of aquatic plants (like algae). Both ponds showed an oligotrophic nature with the presence of poor nutrients and low vegetation.