Abstract Detail



Tropical Biology

Shrotri, Saket [1], Dhargalkar, Rahul [2], P V, Najla [2], GOWDA, VINITA [4].

Do grasslands show flowering synchrony? Quantifying the nature and shifts in  mass-flowering on a plateau from the northern Western Ghats, India.

For an angiosperm, flowering time is critical in order to optimize its reproductive fitness. An individual that flowers too early or too late may face at least one of the following constraints: a) hostile weather conditions, b) declining resources, c) unavailability of pollinators, d) higher competition from other co-flowering species.  Reproductive synchrony is a tendency of individuals to carry out at least some part of the reproductive cycle at the same time as the other members of the population. Thus studying the factors that drive reproductive synchrony in a plant community is a crucial step towards understanding regional flowering seasons.
Here we present a study carried out at Kaas plateau which is one of the high elevation grassland communities of the northern Western Ghats, Maharashtra, India. We address the following question: what is the role of environmental factors and ecological competition in shaping the flowering phenologies of herbaceous plants? We carried out this study between August 2018 and November 2019. We quantified flowering phenologies in 10 randomly distributed transects, where diversity and abundance of 68 herbaceous species belonging to different phenophases (flowering, vegetative, and fruiting) were recorded. We collected daily variations in 4 major environmental parameters (rainfall, wind speed, humidity, and temperature) and compared them with the recorded phenological trends of the species. We observed 36 species (each for ~1.5 hrs) for pollinator visitation rates which were later used to build the bipartite plant-pollinator network.
Results:
(1) Only two environmental factors- rainfall and daily variation in temperature were found to affect the flowering of herbaceous species. We found that, within a year, the plateau experiences extreme phenological and climatic shifts, and only during the monsoon and post-monsoon months the herbaceous species show flowering. These are also the months when least fluctuation in daily temperatures were recorded.
(2) We classified all herbaceous species into four groups according to their floral colors which were temporally partitioned according to their flowering phenology (synchrony index<0.5). Additionally, we found that in each color group the non-mass flowering taxa show near-perfect synchrony (index>0.7) with the ‘mass-flowering’ taxa of the same color group.
(3) ‘Mass-flowering’ taxa were found to be pollinated by the most dominant pollinator(s) while a diverse set of pollinators were observed on ‘non-mass flowering’ taxa. We observed nestedness (28.69) in pollinator networks within color groups. Pollinators also showed a tendency to shift among colors as the flowering season progressed.


1 - Indian Institute Of Science Education And Research Bhopal, Department Of Biological Sciences, Tropical Ecology And Evolution (TrEE) Lab, Room 303, AB3, IISER Bhopal, Bhauri Campus, Bhopal By Pass Road, Bhopal, MP, 462066, India
2 - Indian Institute of Science Education and Research (IISER) Bhopal, Department of Biological Sciences, Room 303, Tropical Ecology and Evolution (TrEE) Lab, AB3, IISER Bhopal,Bhauri Campus, Bhopal By Pass Ro, Bhopal, MP, 462066, India
3 - Indian Institute of Science Education and Research (IISER) Bhopal, Department of Biological Sciences, Room 303, Tropical Ecology and Evolution (TrEE) Lab, AB3, IISER Bhopal,Bhauri Campus, Bhopal By Pass Ro, Bhopal, MP, 462066, India
4 - Indian Institute of Science Education and Research (IISER) Bhopal, Department of Biological Sciences, Room 303, Tropical Ecology and Evolution (TrEE) Lab, AB3, IISER Bhopal, Bhauri Campus, Bhopal By Pass R, Bhopal, MP, 462066, India

Keywords:
Comunity Ecology
sky island
flowering phenology
synchrony
mass flowering
grassland.

Presentation Type: Oral Paper
Session: TROP1, Tropical Biology Contributed Papers
Location: Virtual/Virtual
Date: Tuesday, July 28th, 2020
Time: 10:45 AM
Number: TROP1004
Abstract ID:794
Candidate for Awards:None


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