@phdthesis{black_simulating_2014,
	type = {Bachelors thesis},
	title = {Simulating the future potential of degraded {Mangrove} plots using field data from {Kenya}.},
	abstract = {Despite their well acknowledged ecological and socio-economic importance over the last 50 years there has been a serious decline in global mangrove coverage. The primary cause of which has been anthropogenic activities such as: deforestation; increasing urbanization; and conversion of land for aqua/agriculture. If this decline is not halted then some studies predict that mangroves will cease to exist within this century. One of the most promising means of achieving this is by harnessing mangroves significant carbon sequestration potential to incentivise conservation through carbon credit schemes such as PES and REDD+.
One such example of this is Mikoko Pamoja, a small scale community managed forest project in Gazi Bay, Kenya. Launched in 2013, the aim of this project is to generate income through the sale of avoided deforestation over a twenty year timescale. However the main obstacle faced by Mikoko Pamoja and indeed all similar schemes is the production of reliable estimates how much carbon they will sequester over their operational time scale. These estimates can be produced from long term empirical data although in Kenya especially this is non-existent. An alternative method is to simulate forest growth over the required time period using complex ‘gap dynamic’ computer models. Gap dynamic models are a critically appraised tool for investigating many aspects of forest dynamics, and whilst several mangrove specific models exist none are suitable for providing reliable estimates for the Mikoko Pamoja. Hence the purpose of this project was to construct a simplified gap dynamic model in 6
order to simulate the growth of mangroves at 13 sites around Kenya based on empirical data of the existing forests.
Prior to this however the empirical data was analysed to in order to investigate the frequency distribution of plot biomass (T/ha) at each site. From this assertions were made about the conditions of the existing of forests, although a lack of further evidence in the wider literature left many of these unsubstantiated. In addition to this a prescribed graph of the logarithms of mean tree biomass (Kg) against the logarithms of tree density (No. of trees/ha)
showed that the plots in the data did not conform to the predicted -3/2 selfthinning law. However this was attributed to the disturbed nature of many of the
sites. Finally site-specific values of upper quartiles of plot biomass (T/ha) were
used to abstract high biomass ‘pseudo-control’ plots for use in validation of the
modelling work to follow.
The model produced in this study, SEAM (Simulation of East African
Mangroves), uses functions adapted from the seminal forest gap model
JABOWA in order to simulate growth, competition for light and mortality at the
level of individual trees. Once completed the model was described using the
standardised ODD protocol, before being subjected to basic sensitivity analysis
by evaluating the effects of four different methods of model parametisation.
After simulations of 20 years of forest growth were produced various methods
were utilized to attempt to validate the results. The overall conclusion drawn
from these was that the models results are plausible, especially when compared
to empirical data from other studies. However, due to its inclusion of relatively
few growth-limiting factors the current model is likely to be over-estimating rates
of biomass accumulation.
This created discussion as to whether the current model is fit to achieve the
projects original aim of providing reliable estimates for the Mikoko Pamoja
project. The result of this was inconclusive, although, it prompted numerous
suggestions for possible future work in better validation of the existing model
and also potential modifications to improve its accuracy.},
	school = {Edinburgh Napier},
	author = {Black, Benjamin},
	month = jun,
	year = {2014},
	doi = {10.13140/RG.2.2.20232.49923},
	file = {Black_2014_Simulating the future potential of degraded Mangrove plots using field data.pdf:C\:\\Users\\bblack\\switchdrive\\Zotero\\Black_2014_Simulating the future potential of degraded Mangrove plots using field data.pdf:application/pdf},
}