Assessment the Seasonal Dynamics of Weed Community of Rammohan College: To Assume the Model of Seasonal Dynamics of Weeds of Kolkata

Abstract

The seasonal cycle of plant community is the most important biotic oscillations to mankind. This study built upon previous efforts to develop a comprehensive framework to studying this cycle systematically with the weed communities of Rammohan College. We suggest that the seasonal variation of plant community consists of six distinctive phases in sequence each of which results from the interaction between the inherent biological and ecological processes and the progression of climatic conditions and reflects the unique functioning of plant community at different stages of the growing season.

Introduction

I. INTRODUCTION

The dynamics of plant community consists of diurnal and seasonal cycles. These two cycles are the most important biotic oscillations to mankind.

The diurnal photosynthetic cycle is primarily driven by changes in light availability associated with the rotation of the Earth and is thus relatively predictable. The seasonal cycle, however, is more complex (Rannik et al,2000). It is a process orchestrated by internal biological mechanisms and driven by systematic changes in a suite of inter dependent environmental factors such as temperature, photoperiod, radiation, moisture, and nutrient availability.

The study of the plant community of Rammohan College at the seasonal time scale can be considered as an extension of plant phenology (Gu et al. 2002-2003a;b).

This extension, or “vegetation phenology”, represents the functional aspect of plant phenology while traditional plant phenological studies focus on the structural aspect such as bud break, flowering, leaf coloring and leaf fall. Research on vegetation photosynthetic phenology can enrich the ancient but revived discipline of phenology so that it can become a truly integrative environmental science (Schwartz, 2003).

Sites and Data Used in the Present Study

Rammohan College is located in the heart of the city of Kolkata, West Bengal, India. This area is approximately 300 years old and highly urbanized with little or almost no greenery (22.582952?N & 88.370997?E). The college has got a small garden, where butterflies frequently visit and sometimes complete their life cycle and a large uninhabited open space where weeds are available in plenty in numbers.

The survey has been carried out for a period of five years (10/12/2017 –13/12/2022), in college working days. The roads inside the college campus were used as fixed transects. Weekly observations were carried out during morning hours (08:00 hrs to 10:00 hrs), plants were collected and preserved for identification. Occurrence and Relative abundance has been recorded and all statistical analysis has performed using SPSS 23.

III. DISCUSSION

The seasonal dynamics of weeds of Rammohan College may be a reflection of weed dynamics of Kolkata. The Heat Map (Fig1) is showing abundance from High (+2) to Low/Absent (-2) range. Euphorbia microphylla and Mecardonia procumbance are two dominant weeds of Rammohan College. In Table 2 we found that, individual variance is highest in Jan-February whereas cumulative variance is highest in August September. In Table 3, we found, the number of componants of community is highest in post monsoon (July-August) whereas lowest in winter (January-February). In Table 4, we found, the actual dynamics of composition of plants in different seasons. The Table 1 shows the list of plant species found in Rammohan College (A representative of weed flora of Kolkata).

IV. ACKNOWLEDGEMENT

The authors are thankful to Principal, Rammohan College and Principal, Gurudas College for their support.

References

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Copyright

Copyright © 2024 Krishnendu Sarkar, Mitu De, Daliya Hom Chowdhury, Anindita Das, Moumita Dutta, Shibu Das, Santi Ranjan Dey. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.