Climate Change Impacts on Hydrological Niches of Restionaceae Species in Jonkershoek, South Africa

Abstract

Abstract-The Restionaceae species of the Fynbos biome is part of the Cape Floristic Kingdom is threatened by urbanization, agricultural expansion, groundwater extraction, and climate change. Therefore, it is necessary to assess and monitor the Restionaceae species under the impact of climate change. South Africa is a semi-arid environment, and hydrological factors are the main variables in the determination of species niches. This study investigates the microclimate at Jonkershoek, and examines the impact of climate change to the plant species distribution, thus creating shifts in the hydrological niche. This study generates its own unique microclimate hydrological datasets for modelling species niche. The Restionaceae species and their hydrological niche at the Jonkershoek study area are assessed under future climate change scenario, at a microclimatic level. It provided evidence regarding the importance of the study to understanding the climate change impacts on hydrological niche and on species richness.

Climate Change Impacts on Dwarf Succulents in Namibia as a Result of Changes in Fog and Relative Humidity

“…The future climate variables of fog and relative humidity have been used in the spatial modelling process [15,18] to project the suitable bioclimatic envelope for both Conophytum and Lithops in the present and in the future. In addition, geology, altitude, morphology and soil type were used as environmental constraints.…”

“…with λi = ( λ1, λ2,..., λm) as the weight vector, λi being the weight parameters, fi(x) representing species i's probability distribution, L being the m-dimensional space, each element x is a pixel of the investigated area, and Zλ(x) being the normalized constant, and the probabilities fi(x) represent the relative suitability of the environmental variable in each pixel [13,[15][16][17].…”

“…Therefore, MaxEnt uses a Bayesian approach by which the species probability distribution subject to environmental constraints, are statistically estimated by searching the family of probability distributions under the maximum entropy criterions [15].…”

The Cape Wetland Restionaceae of New Years Peak under a Changing Climate

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