Effect of abiotic factors on the distribution of earthworms in different land use patterns

AbstractThe distribution of earthworms is usually diverse and their numbers fluctuate in relation to the different abiotic factors and land use patterns of the soil. The aim of the present study is to determine the biodiversity, distribution and relative abundance of earthworms under different land use pattern and its relation to abiotic factors (physico-chemical properties) of the soil. Earthworms were collected from different sites on the basis of various environment niches like agriculture fields, gardens, nurseries, along the river and road side etc. by hand sorting method. Physico-chemical analysis of the soil was also done to know the important factors affecting earthworm biodiversity and distribution. Total five species of earthworms belonging to the families Megascolecidae and Octochaetidae were identified: Metaphire posthuma, Lampito mauritti, Amynthas morissi, Eutyphoeus waltoni and Eutyphoeus incommodus. M. posthuma was the most abundant species and found in all the collection sites while other four species were abundantly found in gardens and nurseries. Shannon–Wiener diversity index, Margalef species richness and Pielou’s evenness was ranged from 0.11 to 0.37, 0 to 0.6 and 0 to 0.53 respectively. Principal component analysis also proved that the abiotic factors like pH, moisture, soil texture and OC has strong positive effect on the distribution of earthworm. Earthworm biodiversity and distribution have been found to be positively correlated with type of vegetation and moisture content at the different collection sites and also varied according to soil habitat, soil tillage and land used pattern

Environmental Influence of Soil toward Effective Vermicomposting

Vermicomposting is a process by which the organic waste is converted into manure with the help of earthworms. Growth rate, onset of maturity (clitellum development), rate of reproduction (cocoon production) and population buildup of earthworm during vermicomposting have been depend upon the conditions like temperature, moisture and physico-chemical properties of the feed mixtures. Eisenia fetida was superior to other epigeic species and tolerate wide range of temperature, moisture and pH. Endogeic species produced lesser cocoon than epigeic species and cocoon production decreased at low temperature. Maintenance of temperature and moisture content is the critical step for vermicomposting. Growth and maturation of earthworms was best at 20–25°C temperature with 80–85% moisture content. Increase temperature upto 30°C accelerated growth rate of earthworms and lessened the time to sexual maturity. Earthworms can survive in the soil contaminated with heavy metals by accumulating heavy metals in their tissues

A systematic literature review: Refactoring for disclosing code smells in object oriented software

Context: Reusing a design pattern is not always in the favor of developers. Thus, the code starts smelling. The presence of “Code Smells” leads to more difficulties for the developers. This racket of code smells is sometimes called Anti-Patterns. Objective: The paper aimed at a systematic literature review of refactoring with respect to code smells. However the review of refactoring is done in general and the identification of code smells and anti-patterns is performed in depth. Method: A systematic literature survey has been performed on 238 research items that includes articles from leading Conferences, Workshops and premier journals, theses of researchers and book chapters. Results: Several data sets and tools for performing refactoring have been revealed under the specified research questions. Conclusion: The work done in the paper is an addition to prior systematic literature surveys. With the study of paper the attentiveness of readers about code smells and anti-patterns will be enhanced. Keywords: Code smells, Anti-patterns, Refactorin

Assessment of genotoxic effects of pesticide and vermicompost treated soil with Allium cepa test

Soil forms a huge reservoir of nutrients that sustains life on earth. Anthropogenic and natural impacts have led to degradation of land which declines the overall quality of soil, water or vegetation. The present study involves comparison of genotoxicity of soil procured from two different agricultural sites, pesticide treated soil (PTS) and vermicompost treated soil (VTS). The soil was physico-chemically characterized and showed significant differences in terms of cytotoxicity (root length; mitotic index) and genotoxicity (chromosomal aberrations) in Allium cepa test. The mitotic index of the control after 24 and 48 h was found to be 26.1 ± 1.6 and 26.1 ± 1.3 respectively. Mitotic index was reduced to 10.3 ± 0.9 and 9.7 ± 0.6 in 100% PTS and 24.4 ± 1.7 and 25.4 ± 0.8 in 100% VTS after 24 and 48 h of exposure, respectively. Clastogenic aberrations were found to be highest (54.5%) in 100% PTS which was significantly different from VTS extract. The PTS extracts incurred significantly more cytotoxic and genotoxic effects on A. cepa in comparison to VTS. The result indicates that addition of vermicompost in agriculture field acts as soil ameliorator and plays an important role in promotion of cell division and proliferation, hence good for the plant health and crop productivity

Soil properties changes earthworm diversity indices in different agro-ecosystem

Abstract Background Earthworm communities are generally very sensitive to physico-chemical properties of the soil in different agro-ecosystem i.e. cultivated or non-cultivated which directly or indirectly influence the earthworm survival. The difference in physico-chemical properties of soil at different sites contributed to the formation of population patches for earthworm species. Understanding the physico-chemical properties of soil at a particular site could facilitate the prediction of earthworm species at that site. The objective of the present study was to investigate the diversity, abundance, and distribution of earthworms in cultivated and non-cultivated agroecosystems and their physico-chemical properties affecting the earthworm diversity and abundance. Results Total 10 species of earthworms i.e. Amynthas alexandri, Amynthas morrisi, Eutyphoeus incommodus, Eutyphoeus waltoni, Metaphire birmanica, Metaphire houlleti, Metaphire posthuma, Octochaetona beatrix, Perionyx excavatus, and Polypheretima elongata, were reported. Out of all the reported species, Metaphire posthuma was found to be the most abundant earthworm species in both cultivated and non-cultivated agroecosystems with the occurrence at 56.81% sites. The Shannon-Wiener index (H), Margalef species richness index (DMg) and Pielou species evenness (E) was ranged from 0 to 0.86, 0 to 0.64 and 0.78 to 1 respectively. The principal component analysis resulted in four principal components i.e. PC1, PC2, PC3 and PC4 which contributing variance (%) of 22.96, 19.37, 14.23 and 10.10 respectively. The principal component analysis also showed that physico-chemical parameters of soil such as EC, pH, TDS, texture, OC, moisture, etc. play a critical role in earthworm distribution. Conclusion The conventional farming system has a negative effect on the earthworm diversity in the soil while the physico-chemical properties of soil also have a determinant effect on the same. Earthworms abundance in the present study have significant direct relation with soil properties at a particular site and vice versa. The diversity indices also change due to the conventional farming system which directly affects the earthworm abundance