The Impact of Climatic Factors on Temporal Mosquito Distribution and Population Dynamics in an Area Targeted for Sterile Insect Technique Pilot Trials.

It is widely accepted that climate affects the mosquito life history traits; however, its precise role in determining mosquito distribution and population dynamics is not fully understood. This study aimed to investigate the influence of various climatic factors on the temporal distribution of populations in Mamfene, South Africa between 2014 and 2019. Time series analysis, wavelet analysis, cross-correlation analysis, and regression model combined with the autoregressive integrated moving average (ARIMA) model were utilized to assess the relationship between climatic factors and population density.

A rapid and accurate method of mapping invasive genotypes using Sentinel-2 images.

Background: The management of invasive genotypes depends on reliable and accurate information of their extent and distribution. This study investigated the utility of the multispectral Sentinel-2 imageries to map infestations of the invasive along three riparian ecosystems in the Western Cape Province of South Africa.

Methods: The Sentinel-2 image was acquired from the GloVis website (http://glovis.

Mapping the distribution and tree canopy cover of Jacaranda mimosifolia and Platanus × acerifolia in Johannesburg's urban forest.

This study investigated the distribution and the tree canopy cover (TCC) of the two most prominent street trees (Jacaranda mimosifolia and Platanus × acerifolia) in Johannesburg, using the multispectral SPOT 6 satellite data and field survey GPS points. The importance of the spectral bands (Blue, Green, Red and NIR) and the NDVI index in discriminating between the tree species was quantified using five separability indices (Divergence, Bhattacharyya, Transformed Divergence, Jeffries-Matusita and M-statistic). The visual comparison of the Blue band and the NDVI histograms between the two species and other vegetation type showed the lowest feature overlap, suggesting the highest separability between paired classes.

The impact of Tamarix invasion on the soil physicochemical properties.

The exotic Tamarix species, T. ramosissima and T. chinensis, were introduced into South Africa in the early 1900s reportedly either for ornamental or soil wind erosion control purposes in the mines.

Soil salinity and moisture content under non-native species.

This study investigated, soil salinity and moisture content under the exotic Tamarix in the Olifants River, South Africa, where they predominantly occur. Soil electro-conductivity (EC) was mapped using the electromagnetic induction (EMI) device (EM38 sensor), in three transects laid along the river from as close to the water source outward towards the bank of the River at 50 m apart. This was supported by three soil EC and moisture measurements from each of the three transects at a soil depth of 0-100 cm at intervals of 10 cm using soil EC meter and Amplitude Domain Reflectometry (ADR) sensor, respectively.

efficiency in salt excretion and physiological tolerance to salt-induced stress in South Africa.

This study, investigated the salt excretion efficiency and the level of the physiological response to salt-induced stresses between the native and exotic species as well as their hybrids ( × and × ). Ten potted plants from each of the five taxa were exposed to salt at a concentration of 3% (w/w) (180 mM) for 3 weeks. Measurements of electro-conductivity (EC), physiological parameters such as stomatal conductance, chlorophyll fluorescence, and water pressure and plant growth were taken from salt-treated and control plants.

Sequestration of precious and pollutant metals in biomass of cultured water hyacinth (Eichhornia crassipes).

The aim of this study was to investigate the overall root/shoot allocation of metal contaminants, the amount of metal removal by absorption and adsorption within or on the external root surfaces, the dose-response of water hyacinth metal uptake, and phytotoxicity. This was examined in a single-metal tub trial, using arsenic (As), gold (Au), copper (Cu), iron (Fe), mercury (Hg), manganese (Mn), uranium (U), and zinc (Zn). Iron and Mn were also used in low-, medium-, and high-concentration treatments to test their dose effect on water hyacinth's metal uptake.

The capacity of aquatic macrophytes for phytoremediation and their disposal with specific reference to water hyacinth.

The actual amount of fresh water readily accessible for use is <1 % of the total amount of water on earth, and is expected to shrink further due to the projected growth of the population by a third in 2050. Worse yet are the major issues of water pollution, including mining and industrial waste which account for the bulk of contamination sources. The use of aquatic macrophytes as a cost-effective and eco-friendly tool for phytoremediation is well documented.