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This review provides an overview of the progress made in remote sensing application for soil moisture, vegetation and inundation mapping in wetland environments. The main objective of the paper was to assess the link between soil moisture variations and vegetation characteristics in wetland remote sensing studies. To achieve this objective, relevant literature was gathered from established search engines, e.g. Science Direct and Web of Science, along with specific search strategies and key phrases. Three hundred and ninety-three journal articles on wetland remote sensing published between 1980 and 2023 were collected and subjected to a comprehensive analysis. The findings indicate that remote sensing of wetland moisture, vegetation and inundation has been increasing, from three published work in the 1980s to 22 in the 1990s, to 88 between 2001 and 2010, and to 278 between 2011 and 2023. Results showed that there has been an improvement in the application of remote sensing in mapping of wetland moisture, inundation and vegetation in Africa between 2015 and 2023. Despite wide application of remote sensing to map these aspects, very few studies (2.1%) have focused on establishing the relationship between them. The analysis indicated that the launch of new Sentinel-1 radar and Sentinel-2 optical sensors in addition to the Landsat series, along with a variety of analytical methods, provided a great opportunity for derivation of soil moisture and vegetation data which can be used to establish the soil moisture–vegetation nexus. [ABSTRACT FROM AUTHOR]

The study assesses the nexus between the drivers of wetland utilisation patterns, land-use and land-cover change (LULCC) and the current status of provisioning and cultural services in Driefontein and Intunjambili wetlands, Zimbabwe. A total of 280 household questionnaires were administered together with semi-structured interviews conducted with key informants in the two wetlands. Qualitative data were analysed using the content analysis method whereas descriptive and inferential statistics were used for quantitative data. LULCC was assessed using Landsat and Sentinel data for the years 1999, 2009 and 2019. Supervised classification was performed using the Maximum Likelihood Classification (MLC) algorithm in ArcMap 10.5. Eighty-six percent of Driefontein and 75% of Intunjambili households indicated that wetland use for horticulture farming was the predominant activity, but for different reasons in the two areas. In Intunjambili wetland, horticultural farming was mainly for subsistence use due to the prevailing semi-arid conditions. This was different from Driefontein, where market availability for horticultural produce was the major factor behind commercialised wetland use. Results of the LULCC analysis showed an increase in the spatial extent of the cultivated area in the two wetland areas, at the expense of vegetation and water and some of the associated ecosystem services. The studied wetlands provide cultural services since they are used as sites for research and academic excursions. The variations in the anthropogenic drivers of wetland use in Driefontein and Intunjambili show that location-specific wetland studies are important to inform appropriate wetland scale utilisation and management policies and strategies that result in the maintenance of ecosystem services. [ABSTRACT FROM AUTHOR]

The paper assesses trends in use of earth observation data in wetland conditions monitoring and assessment in Zimbabwe from 1980 to 2019. Reviewed literature shows academia and research institutions (69.8%), government agencies (14%) and international development partners (16.3%) as the main users of remotely sensed data in wetland ecological assessments and monitoring. There is more reliance by the abovementioned stakeholders on freely available low‐cost resolution imagery from Landsat (62.9%) and Moderate Resolution Imaging Spectroradiometer (14.3%). Other stakeholders, however, are reliant on high‐resolution imagery like Rapid Eye (5.7%) and aerial photography (11.4%). Satellite images in wetland management in Zimbabwe are used for land use land cover change detection (42.1%), vegetation health monitoring (21.1%), water quantity monitoring (5.3%), water quality monitoring (13.2%) and wetland mapping (18.4%). The identified challenges faced by different stakeholders to effectively utilise EO data include high cost of high‐resolution imageries, limited expertise, inadequate equipment and software. Since the cost of high‐resolution satellite imagery mainly constraints the acquisition of suitable satellite data to assess the small wetlands that dominate Zimbabwe's landscape, there is need to promote use of recently launched freely available high‐resolution Sentinel data to improve the ecological assessment of wetland conditions. [ABSTRACT FROM AUTHOR]

The research examines challenges and opportunities of biogas technology adoption to achieve sustainable household energy in Ward 4 of Domboshava communal area, Zimbabwe. The research adopted both qualitative and quantitative research techniques. A total of 65 questionnaires were randomly distributed to households using biogas. Purposive sampling technique was employed to select key informants from the Environmental Management Agency, Netherlands Development Organisation, Zimbabwe Energy Regulatory Authority, Environment Africa and the Ward Councillor. The study revealed that the level of education attained do not influence biogas adoption (p > 0.05) whereas funds availability, awareness, promoters and gender of the household head were seen to have a major effect (p < 0.05). The benefits of biogas technology noted by households were that it cooks fast, provides clean energy and at the same time reducing the frequency of fire wood collection in the forest. Challenges such as lack of adequate knowledge about the technology and lack of required financial and material resources compromised the adoption of biogas technology by the households in Ward 4. The study recommends that relevant government agencies should provide accessible technical services and set up demonstration centres in every ward with a view of encouraging rural households to adopt biogas technology. [ABSTRACT FROM AUTHOR]

Wetlands are among the most threatened natural ecosystems in developing countries. Loss of wetlands is attributed to, among other factors, inadequacy in information on the resource's value to rural communities. This paper investigates wetland utilisation patterns as well as the status of benefits derived by surrounding communities in Runde, Tongogara and Vungu rural districts of Zimbabwe. Two sets of questionnaires were used to gather data from 123 household heads and 60 teenagers. Snowball sampling was used to select 14 elderly people for semi-structured interviews. Land cover changes were established through analysis of the 2013 RapidEye imagery and aerial photographs (1985 and 1996). The results of land cover change analysis indicate an increase in spatial extent of cultivated area, water and bare land, and a decrease in the area covered by sparse and dense vegetation. Meanwhile, the majority of households revealed that there is no change in wetland utilisation patterns as cultivation continues to dominate. Increase in area under cultivation is driven by multidecadal rainfall variability, making dryland farming unproductive; food security projects implemented by donors; political interference; and availability of market for horticultural products. The level of households’ dependency on wetlands is generally high, although spatially heterogeneous. Overall, information on community dependence on wetlands should be accounted for and factored into local conservation planning, since it influences use and conservation of wetlands. [ABSTRACT FROM PUBLISHER]

This study presents a comprehensive literature review exploring the effects of artisanal mining on wetlands in semi-arid regions of sub-Saharan Africa. The review encompasses relevant literature sourced from Google Scholar, SCOPUS and Web of Science databases, using specific key search terms. The findings reveal a substantial body of research dedicated to artisanal mining. The study findings reveal that wetlands are currently facing threats, and extensive scientific research has been conducted on wetland monitoring and assessment. Ecohydrological and geomorphological assessment studies are found to be critical in understanding wetland vulnerability. Among the frequentist-interpretation methods used in most wetland assessment studies, Bayesian belief networks (BBNs), geospatial and earth observation analysis, and expert elicitation are prominently highlighted. In addition, many countries, including Congo, Niger, South Africa, and Zimbabwe, have experienced extensive artisanal mining activities, leading to notable wetland and habitat losses, compromised eco-hydrology integrity, riverbed siltation, and severe mercury pollution, resulting in neurological poisoning of both invertebrate and vertebrate wetland species. The review underscores the urgency of adopting a transdisciplinary scientific approach to wetland monitoring and assessment to prevent further degradation of these ecosystems. By embracing such an approach, scientists can gain a comprehensive understanding of the impacts of human activities on wetlands and develop more effective strategies for mitigating these adverse effects. • Illegal artisanal mining has a regional impact on the integrity and functioning of wetlands. • Wetlands are extremely vulnerable due to their size, hydrology, and ecological features. • Wetland monitoring and assessment require a multidisciplinary scientific approach. • In most wetland assessment studies, frequentist interpretation methods are used. [ABSTRACT FROM AUTHOR]

This study assessed the benefits and challenges associated with local community involvement in biodiversity conservation in the Blouberg Nature Reserve (BNR) of South Africa. To achieve this, a descriptive research design was used in the study. Three hundred and thirty‐five households from four villages scattered around the nature reserve were selected using a stratified systematic sampling procedure to participate in a household questionnaire survey. The BNR Manager was purposefully selected for an in‐depth structured interview so that an overview of socio‐economic benefits and challenges to the community from the park's perspective could be known. Field data collection was conducted during the month of June 2019. Descriptive and inferential statistical methods as well as thematic analysis were used to analyse the field data. The main study findings indicated that the community members do not obtain sufficient socio‐economic benefits from the nature reserve. The majority of the household respondents (89.6%) were not participating in biodiversity conservation in the nature reserve, despite possessing knowledge about nature conservation. The chi‐square test results showed a significant association between household respondents' conservation involvement and access to natural benefits (p = 0.008), and not cultural benefits (p = 0.740). Moreover, the chi‐square test results further show no significant association between household attributes (gender and age) and knowledge of the role of nature reserve (p > 0.05), whereas education had a bearing on the knowledge possessed by households (p < 0.05). Overall, the findings indicate the need for more community involvement to support biodiversity conservation within nature reserves. [ABSTRACT FROM AUTHOR]

This work assesses land cover changes on the Upper Runde sub-catchment, Zimbabwe, and associated effects on sedimentation rates and risks. The model was implemented using the common Geographic Information Systems tools. To achieve this objective, mean annual and monthly rainfall, as well as sediment data, were used (December 2016 and April 2017). Land use and land cover changes were assessed using time-series Landsat data acquired between the years 2000 and 2016. The Revised Universal Soil Loss (RUSLE) model was used to model sedimentation rates in the catchment. Land cover results showed that the catchment experienced significant (α = 0.05) changes during the period of monitoring. For example, forests and woodlands decreased by 39% and 23% between 2000 and 2016, respectively. Sedimentation results indicated that the catchment had an average sediment load of 6272 mg/l as compared to the expected maximum of 3000 mg/l. RUSLE soil loss simulation results showed an increase in average soil loss from 1.2 ton/ha/yr. in 2000 to 1.7 ton/ha/yr. in 2016 and an increase in sediment yield by 19.2% from 3476 mg/l in 2000–4144 mg/l in 2016. Overall, the findings of this study demonstrate that the catchment experiences high sedimentation. Therefore, catchment sediment monitoring and soil conservation actions should be a priority. • RUSLE soil loss simulation results showed an increase in average soil loss. • Catchment degradation. • An increase in sedimentation is a result of changes in land use/land cover. • Water sources are threatened by sedimentation. [ABSTRACT FROM AUTHOR]