Abstract
Relative growth rate (RGR) is an important parameter in plant growth models. However, no field measurements of RGR have been made in Cyperus papyrus (papyrus) wetlands. In this study, the growth dynamics of aerial shoots were investigated in a tropical papyrus wetland. The aim was to estimate temporal changes in the growth rates, and also establish the effect of water level and temperature change on total culm number, culm recruitment and senescence. Dry weights of shoots during their life cycle were determined using a non-destructive method after establishment of relationship between culm diameter and dry weight. Measurements were made over period of seven months. During the course of the measurements, culm density significantly increased from 16.1 to 35.9 culms.m-2. There were significant changes in both culm recruitment and senescence. Maximum RGR of developing culms was 1.04 g g-1 d-1. Using a culm density of 27 per m-2, productivity range was 16.74 to 37.37 g m-2 d-1. There was an inverse and significant relationship between rate of change in leaf weight ratio (LWR) and RGR of the culms. In conclusion, RGR of the aerial shoot development was controlled by rate of change in LWR from 41 to 156 days of growth. There was a strong and negative influence of water level fluctuation on total culm density.
Highlights
Cyperus papyrus is a large herbaceous sedge commonly found in waterlogged environments in the African tropics
It was hypothesized that growth rate of shoots and their total culm density, recruitment and senescence are dependent on water level and water temperature variation in the wetland
Water level rise during flooding was characterized by subsurface flow in the wetland and open water channels were formed in some areas
Summary
Cyperus papyrus (papyrus) is a large herbaceous sedge commonly found in waterlogged environments in the African tropics These wetland ecosystems provide ecological and socio-economic services related to the harvesting of aerial biomass, wastewater treatment, hydrological functions and climate modification [1]. The potential economic importance of papyrus wetlands has stimulated many studies on growth and development of the vegetation. Mathematical equations in the form of fitted functions have been employed to analyze time series of dry weight [21]-[23] The objective of this investigation was to estimate the temporal changes in growth and development in a papyrus wetlands. This involved determining the pattern of individual papyrus shoot relative growth rates. It was hypothesized that growth rate of shoots and their total culm density, recruitment and senescence are dependent on water level and water temperature variation in the wetland
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
