South African Land Degradation Monitor (SALDI) – A German – South African SPACES collaboration to advance land degradation assessments

2020 ◽  
Author(s):  
Jussi Baade ◽  
Andreas Kaiser ◽  
Keyword(s):  
South Africa ◽  
South African ◽  
Land Degradation ◽  
Land Surface ◽  
Soil Degradation ◽  
Assessment Tools ◽  
Automated System ◽  
Observation Data ◽  
Clean Water ◽  
Cooperative Research

<p>South Africa is greatly affected by land degradation, partly due to the high variability of its climatic conditions, the strong population growth and resulting economic demands. Thus reaching a number of SDGs, like achieving food security (#2), access to clean water (#6), and the sustainable use of terrestrial (#15) and marine (#14) resources represents a clear challenge under the present global change pressures. Land degradation has been linked in South Africa to the terms veld degradation and soil degradation and has been addressed by numerous measures. But there is still uncertainty on the extent of human induced land degradation as compared to periodic climate induced land surface property changes.</p><p>In cooperation with South African institutions and stakeholders (ARC-ISCW, SAEON, SANParks, SANSA, Stellenbosch University and University of the Free State, Equispectives Research and Consulting Services, Nuwejaars Wetlands SMA), the overarching goal of SALDi is to implement novel, adaptive, and sustainable tools for assessing land degradation in multi-use landscapes in South Africa. Building upon the state of the art in land degradation assessments, the project aims to advance current methodologies for multi-use landscapes by innovatively incorporating inter-annual and seasonal variability in a spatially explicit approach. SALDi takes advantage of the emerging availability of high spatio-temporal resolution Earth observation data (e.g. Copernicus Sentinels, DLR TanDEM-X, NASA/USGS Landsat program), growing sources of in-situ data and advancements in modelling approaches. Particularly, SALDi aims to:</p><ol><li>i) develop an automated system for high temporal frequency (bi-weekly) and spatial resolution (10 to 30 m) change detection monitoring of ecosystem service dynamics,</li> <li>ii) develop, adapt and apply a Regional Earth System Model (RESM) to South Africa and investigate the feedbacks between land surface properties and the regional climate,</li> </ol><p>iii)    advance current soil degradation process assessment tools for soil erosion, as this process represents an intrinsic limiting factor for biomass production and other regulating, supporting and provisioning ecosystem services, like providing clean water.</p><p>The aim of this presentation is to introduce this new cooperative research project to the EGU Community and to seek new opportunities for collaboration.</p>

South African Land Degradation Monitor (SALDI) – An overview of recent advancements

2021 ◽  
Author(s):  
Jussi Baade ◽  
Christiane Schmullius ◽  
Marcel Urban ◽  
Harald Kunstmann ◽  
Patrick Laux ◽  
...  
Keyword(s):  
South Africa ◽  
South African ◽  
Land Degradation ◽  
Ecosystem Service ◽  
Land Surface ◽  
Soil Degradation ◽  
Assessment Tools ◽  
Geological Conditions ◽  
Rainfall Region ◽  
Semi Arid

<p>For many decades the problem of land degradation has been an issue in South Africa. This is mainly due to the high variability of the mostly semi-arid climatic conditions providing a challenging environmental setting. Strong population growth and resulting socio-economic pressure on land resources aggravate the situation. Thus, reaching a number of Sustainable Development Goals (SDGs), like achieving food security (#2), access to clean water (#6), and the sustainable use of terrestrial (#15) and marine (#14) resources represents a challenge.</p><p>In South Africa, land degradation has been linked to the terms veld degradation and soil degradation and has been addressed by numerous measures over the past decades. However, there is still uncertainty on the extent of human induced land degradation as compared to periodic climate induced land surface property changes. In cooperation with South African institutions and stakeholders the overarching goal of SALDi is to implement novel, adaptive, and sustainable tools for assessing land degradation in multi-use landscapes. Building upon the state of the art in land degradation assessments, the project aims to advance current methodologies by innovatively incorporating inter-annual and seasonal variability in a spatially explicit approach. SALDi takes advantage of the emerging availability of high spatio-temporal resolution Earth observation data (e.g. Copernicus Sentinels, DLR TanDEM-X, NASA/USGS Landsat), growing sources of in-situ data and advancements in modelling approaches.</p><p>SALDi focusses on six study sites representing a major climate gradient from the (humid) winter-rainfall region in the SW across the (semi-arid) year-round rainfall to the (very humid) summer-rainfall region in the NE. The sites cover also different geological conditions and different agricultural practices. These include commercial, rain-fed and irrigated cropland, free-range cattle and sheep farming as well as communal and subsistence farming. Protected areas within our study regions represent benchmark sites, providing a foundation for baseline trend scenarios, against which climate-driven ecosystem-service dynamics of multi-used landscapes (cropland, rangeland, forests) will be evaluated.</p><p>The aim of this presentation is to provide an overview of recent activities and advancements in the three thematic fields addressed by the project:</p><p>i) to develop an automated system for high temporal frequency (bi-weekly) and spatial resolution (10 to 30 m) change detection monitoring of ecosystem service dynamics,</p><p>ii) to develop, adapt and apply a Regional Earth System Model (RESM) to South Africa and investigate the feedbacks between land surface properties and the regional climate,</p><p>iii) to advance current soil degradation process assessment tools for soil erosion.</p><p>A number of additional SALDi team member presentations will provide detailed information on current developments.</p>

Development of earth observation data cubes for monitoring land degradation processes in South Africa

2021 ◽  
Author(s):  
Insa Otte ◽  
Nosiseko Mashiyi ◽  
Pawel Kluter ◽  
Steven Hill ◽  
Andreas Hirner ◽  
...  
Keyword(s):  
South Africa ◽  
Land Use ◽  
Ecosystem Services ◽  
Land Use Change ◽  
South African ◽  
Land Degradation ◽  
Earth Observation ◽  
Observation Data ◽  
Data Cubes ◽  
Earth Observation Data

<p>Global biodiversity and ecosystem services are under high pressure of human impact. Although avoiding, reducing and reversing the impacts of human activities on ecosystems should be an urgent priority, the loss of biodiversity continues. One of the main drivers of biodiversity loss is land use change and land degradation. In South Africa land degradation has a long history and is of great concern. The SPACES II project SALDi (South African Land Degradation Monitor) aims for developing new, adaptive and sustainable tools for assessing land degradation by addressing the dynamics and functioning of multi-use landscapes with respect to land use change and ecosystem services. SPACES II is a German-South African “Science Partnerships for the Adaptation to Complex Earth System Processes”. Within SALDi ready-to-use earth observation (EO) data cubes are developed. EO data cubes are useful and effective tools using earth observations to deliver decision-ready products. By accessing, storing and processing of remote sensing products and time-series in data cubes, the efficient monitoring of land degradation can therefore be enabled. The SALDi data cubes from optical and radar satellite data include all necessary pre-processing steps and are generated to monitor vegetation dynamics of five years for six focus areas. Intra- and interannual variability in both, a high spatial and temporal resolution will be accounted to monitor land degradation. Therefore, spatial high resolution earth observation data from 2016 to 2021 from Sentinel-1 (C-Band radar) and Sentinel-2 (multispectral) will be integrated in the SALDi data cube for six research areas of 100 x 100 km. Additionally, a number of vegetation indices will be implemented to account for explicit land degradation and vegetation monitoring. Spatially explicit query tools will enable users of the system to focus on specific areas, like hydrological catchments or blocks of fields.</p>

Earth Observation Strategies for degradation monitoring in South Africa with Sentinels – Results from the SPACES 2 SALDi-project 

2021 ◽  
Author(s):  
Christiane Schmullius ◽  
Marcel Urban ◽  
Kai Heckel ◽  
Hilma Sevelia Nghiyalwa ◽  
Andreas Hirner ◽  
...  
Keyword(s):  
South Africa ◽  
Time Series ◽  
Soil Moisture ◽  
Ecosystem Services ◽  
South African ◽  
Land Degradation ◽  
Ecosystem Service ◽  
Data Cube ◽  
Assessment Tools ◽  
Individual Development

<p>The project ‘South African Land Degradation Monitor (SALDi)’ contributes to the German-South African Science Program SPACES by addressing the dynamics and functioning of multi-use landscapes with respect to land use, land cover change, water fluxes, and implications for habitats and ecosystem services. Particularly, SALDi aims: i) to develop an automated system for high temporal (bi-weekly) and spatial resolution (10 to 30 m) change detection monitoring of ecosystem service dynamics, ii) to develop, adapt and apply a Regional Earth System Model (RESM) to South Africa and investigate the feedbacks between land surface properties and the regional climate, iii) to advance current soil degradation process assessment tools as a limiting factor for ecosystem services. Protected areas (SANParks and other) within our six study regions represent benchmark sites, providing a foundation for baseline trend scenarios, against which climate-driven ecosystem service dynamics of multi-used landscape (cropland, rangeland, forests) are evaluated. Our study regions follow a climatic SW-NE transect: 1-Overberg, 2-Kai !Garib/Augrabies Falls, 3-Sol Plaatje/Kimberley, 4-Mantsopa/Ladybrand, 5-Bojanala Platinum/Pilanesberg, 6-Ehlanzeni /Mpumalanga.</p><p>We are utilizing Sentinel-1A/B C-Band VV/VH-SAR time series with a 10 m resolution. The revisit time is 12 days on average for South Africa. Pre-processing is done using pyroSAR, a Python framework for large-scale SAR-processing providing processing utilities in ESA’s Sentinel Application Platform (SNAP) as well as GAMMA Remote Sensing software. The first two analytical approaches for the evaluation of the Sentinel-1 time series to detect surface changes, are based on the recognition of irregularities in the radar backscatter or coherence dynamics. Sentinel-2A/B data were pre-processed to L2A and used to calculate a wide range of vegetation indices (e.g. NDVI, EVI, SAVI, REIP) using DLR’s Sen2Cor-processor. The time frame starts with the first Sentinel-1 and -2 acquisitions and continues. The analysis-ready data, that is, harmonized, standardized, interoperable, radiometrically and geometrically consistent data, is being ingested in the SALDi Data Cube. Algorithms and models for developing products such as land degradation indicators are being developed using Jypiter notebooks. SANSA in collaboration with SARAO (South African Radio Astronomy Observatory), is developing the open data cube Digital Earth South Africa (DESA) based on SPOT data. Other datasets from different sensors will be ingested at a later stage. SALDi’s Data Cube will be open access to make it available to the wider scientific community, and also for teaching and training purposes. The application/use of the individual development stages should be possible on the fly for the partners in South Africa. The SASSCAL platform shall be used for distribution of the finalised SALDi Data Cube.</p><p>This presentation demonstrates results from hyper-temporal Sentinel-1 and -2 timeseries concerning woody cover mapping and breakpoint analyses of the complex savanna systems, invasive slangbos (Seriphium plumosum) bush encroachment in grassland areas and regional soil moisture retrievals. Validation has been performed by cross-comparisons with VHR airborne DMC surface products, field trips and permanently installed soil moisture networks and interaction with local South African stakeholders.</p><p> </p>

Evaluating the role of soil physical properties on simulated land-atmosphere interactions over South Africa using coupled atmosphere-hydrological modeling

2021 ◽  
Author(s):  
Zhenyu Zhang ◽  
Patrick Laux ◽  
Joël Arnault ◽  
Jianhui Wei ◽  
Jussi Baade ◽  
...  
Keyword(s):  
South Africa ◽  
Physical Properties ◽  
Land Degradation ◽  
Land Surface ◽  
Soil Physical Properties ◽  
Near Surface ◽  
Soil Database ◽  
Global Soil ◽  
The Impact

<p>Land degradation with its direct impact on vegetation, surface soil layers and land surface albedo, has great relevance with the climate system. Assessing the climatic and ecological effects induced by land degradation requires a precise understanding of the interaction between the land surface and atmosphere. In coupled land-atmosphere modeling, the low boundary conditions impact the thermal and hydraulic exchanges at the land surface, therefore regulates the overlying atmosphere by land-atmosphere feedback processes. However, those land-atmosphere interactions are not convincingly represented in coupled land-atmosphere modeling applications. It is partly due to an approximate representation of hydrological processes in land surface modeling. Another source of uncertainties relates to the generalization of soil physical properties in the modeling system. This study focuses on the role of the prescribed physical properties of soil in high-resolution land surface-atmosphere simulations over South Africa. The model used here is the hydrologically-enhanced Weather Research and Forecasting (WRF-Hydro) model. Four commonly used global soil datasets obtained from UN Food and Agriculture Organization (FAO) soil database, Harmonized World Soil Database (HWSD), Global Soil Dataset for Earth System Model (GSDE), and SoilGrids dataset, are incorporated within the WRF-Hydro experiments for investigating the impact of soil information on land-atmosphere interactions. The simulation results of near-surface temperature, skin temperature, and surface energy fluxes are presented and compared to observational-based reference dataset. It is found that simulated soil moisture is largely influenced by soil texture features, which affects its feedback to the atmosphere.</p>

Assessing the interactions of atmosphere and land surface over South Africa with convective-permitting coupled atmospheric-hydrological modeling

2020 ◽  
Author(s):  
Zhenyu Zhang ◽  
Joel Arnault ◽  
Patrick Laux ◽  
Jussi Baade ◽  
Harald Kunstmann
Keyword(s):  
South Africa ◽  
Energy Budget ◽  
Land Degradation ◽  
Land Surface ◽  
Hydrological Modeling ◽  
Soil Depth ◽  
Atmospheric Modeling ◽  
Subsurface Water ◽  
Earth System ◽  
Potential Productivity

<p>Land degradation, as a major issue in South Africa, undermines water resources and land potential productivity, and threatens the ecosystem biodiversity and human activities. In the scope of accurately assessing the land degradation processes in multi-use landscapes, the atmosphere-land surface relations and the dynamics of land surface state variabilities need to be addressed in a detail. This requires Earth System modeling approaches jointly considering high-resolution atmospheric modeling, land surface and hydrological modeling frameworks. This study investigates the atmosphere-land interactions and land surface water-energy budget for South Africa using the Earth System Model WRF-Hydro. WRF-Hydro is the fully coupled atmosphere-land surface-hydrology modeling system, which enhances the Weather Research and Forecasting model with the overland and subsurface water routing processes. In the WRF-Hydro modeling setup, the atmospheric part is configured in a convection-permitting spatial resolution at 4 km, with horizontal grids of 650 × 500 points, covering area of Southern Africa. In the land surface, the gridded hydrological processes are routed on a 400 m fine hydrological subgrid, within a soil depth of 2 m. In this study, we perform the coupled simulation for the year of 2010 and show the validation of modeling results with multiple reference datasets. The water-energy budget in the land surface from coupled WRF-Hydro simulation is assessed on 22 primary hydrological drainage regions. Model results show that coupled atmospheric-hydrological modeling is able to represent the regional water and energy budget, and to resolve atmosphere-land surface interactions. This allows the further usage of the coupled atmospheric-hydrological modeling in the context of land degradation studies, e.g. under different land-use scenarios.</p>

I.—The Geological History of South Africa

1906 ◽  
Vol 3 (3) ◽  
pp. 97-104 ◽  
Author(s):  
F. H. Hatch
Keyword(s):  
South Africa ◽  
South African ◽  
Coastal Area ◽  
Land Surface ◽  
Geological History ◽  
Physical Conditions ◽  
History Of ◽  
The Subject ◽  
History Of The South ◽  
Broad Outline

The subject of this address is a brief acount of the succession, thickness, and geological history of the South African, and more especially of the Transvaal, formations. The information necessary for such an account is of course very incomplete, but in broad outline the succession is now known, and some speculation as to the physical conditions that prevailed during the building up of the region may perhaps be permitted. I propose to deal with the period of the geological history of this country that came to an end with the close of Karroo times. The Karroo period ends with the Stormberg rocks (Rhæitic), and since that time South Africa has, with the exception of a small coastal area, been a land surface, and the rocks have consequently been exposed uninterruptedly to the forces of denudation.

scholarly journals Language Assessment for Children With a Range of Neurodevelopmental Disorders Across Four Languages in South Africa

2018 ◽  
Vol 27 (2) ◽  
pp. 602-615 ◽  
Author(s):  
MaryAnn Romski ◽  
Juan Bornman ◽  
Rose A. Sevcik ◽  
Kerstin Tönsing ◽  
Andrea Barton-Hulsey ◽  
...  
Keyword(s):  
South Africa ◽  
South African ◽  
Neurodevelopmental Disorders ◽  
Rating Scale ◽  
Language Skills ◽  
Assessment Tools ◽  
Point Scale ◽  
Language Measures ◽  
Language Profiles ◽  
Valuable Function

Purpose The purpose of this study is (a) to examine the applicability of a culturally and linguistically adapted measure to assess the receptive and expressive language skills of children with neurodevelopmental disorders (NDDs) in South Africa and then (b) to explore the contributions of 2 additional language measures. Method In Part 1, 100 children with NDD who spoke Afrikaans, isiZulu, Setswana, or South African English were assessed on the culturally and linguistically adapted Mullen Scales of Early Learning (MSEL). Clinicians independently rated the children's language skills on a 3-point scale. In Part 2, the final 20 children to be recruited participated in a caregiver-led interaction, after which the caregiver completed a rating scale about their perceptions of their children's language. Results Performance on the MSEL was consistent with clinician-rated child language skills. The 2 additional measures confirmed and enriched the description of the child's performance on the MSEL. Conclusions The translated MSEL and the supplemental measures successfully characterize the language profiles and related skills in children with NDD in multilingual South Africa. Together, these assessment tools can serve a valuable function in guiding the choice of intervention and also may serve as a way to monitor progress.

scholarly journals Translating tools for better parent-based assessment: An exploratory study

2015 ◽  
Vol 62 (1) ◽  
Author(s):  
Shabnam Abdoola
Keyword(s):  
South Africa ◽  
School Readiness ◽  
South African ◽  
Assessment Tools ◽  
Age Group ◽  
The South ◽  
Indian Language ◽  
Language And Culture ◽  
Intervention Measures ◽  
Childhood Intervention

Background: Current speech language assessment and intervention measures are not always culturally valid, as they are not standardised specifically for the various cultural groups within the South African population; and thus need to be adapted.Objectives: The objective of this study was to examine the appropriateness and utility of translations of the Ages & Stages Questionnaire (ASQ) instrument (60 month age group) from English to the Hindi language and culture, which is represented in South Africa. Methods: Biographical questionnaires, ASQ and evaluation thereof were translated in Hindi and completed by parents of 15 typically developing South African preschool children of Indian origin, at the 60 month age level (including children between 57 and 66 months). Results: Participants reported that the questions were well phrased, and that illustrations and tips helped them to complete the questionnaires quickly and accurately. They preferred to be questioned in Hindi, which helped them understand the questions and made it easier to provide the necessary information to answer the questions. Conclusions: In conclusion, it is evident that this translation of the ASQ (60 month age group) from English to Hindi served as an appropriate tool for use with the middle socioeconomic class Hindi (Indian) language and culture. The results of this study would assist to determine the functionality of culturally and linguistically valid assessment tools for different populations, and would contribute to the development of Early Childhood Intervention as a whole in South Africa. It would also contribute to the development of multilingual informal school-readiness screening questionnaires appropriate for the South African context. This is particularly relevant, as school-readiness assessments take place at 60 months to ensure that the child is ready to learn by school age (6–7 years).[PDF to follow]

scholarly journals Twelve-month mental disorders in South Africa: prevalence, service use and demographic correlates in the population-based South African Stress and Health Study

2007 ◽  
Vol 38 (2) ◽  
pp. 211-220 ◽  
Author(s):  
D. R. Williams ◽  
A. Herman ◽  
D. J. Stein ◽  
S. G. Heeringa ◽  
P. B. Jackson ◽  
...  
Keyword(s):  
Mental Health ◽  
South Africa ◽  
Mental Disorders ◽  
South African ◽  
Service Use ◽  
Assessment Tools ◽  
Health Study ◽  
National Study ◽  
Dsm Iv ◽  
Stress And Health

BackgroundSouth Africa's history and current social conditions suggest that mental disorders are likely to be a major contributor to disease burden, but there has been no national study using standardized assessment tools.MethodThe South African Stress and Health Study was a nationally representative in-person psychiatric epidemiological survey of 4351 adults (aged ⩾18 years) that was conducted as part of the WHO World Mental Health (WMH) Survey Initiative between January 2002 and June 2004. Twelve-month prevalence and severity of DSM-IV disorders, treatment, and sociodemographic correlates were assessed with Version 3.0 of the WHO Composite International Diagnostic Interview (CIDI 3.0).ResultsThe 12-month prevalence of any DSM-IV/CIDI disorder was 16.5%, with 26.2% of respondents with disorder classified as severe cases and an additional 31.1% as moderately severe cases. The most common disorders were agoraphobia (4.8%), major depressive disorder (4.9%) and alcohol abuse or dependence (4.5%). Twenty-eight percent of adults with a severe or moderately severe disorder received treatment compared to 24.4% of mild cases. Some 13.8% of persons with no disorder received treatment. Treatment was mostly provided by the general medical sector with few people receiving treatment from mental health providers.ConclusionsPsychiatric disorders are much higher in South Africa than in Nigeria and there is a high level of unmet need among persons with severe and moderately severe disorders.

Reframing Xenophobia in South Africa as Colour-Blind: The Limits of the Afro Phobia Thesis

2020 ◽  
Vol 17 (3) ◽  
pp. 433-444
Author(s):  
Amanuel Isak Tewolde
Keyword(s):  
South Africa ◽  
South African ◽  
Analytical Framework ◽  
Conflict Theory ◽  
Black African ◽  
South Africans ◽  
Theoretical Perspectives ◽  
Online Newspaper ◽  
Close Proximity ◽  
Realistic Conflict Theory

Many scholars and South African politicians characterize the widespread anti-foreigner sentiment and violence in South Africa as dislike against migrants and refugees of African origin which they named ‘Afro-phobia’. Drawing on online newspaper reports and academic sources, this paper rejects the Afro-phobia thesis and argues that other non-African migrants such as Asians (Pakistanis, Indians, Bangladeshis and Chinese) are also on the receiving end of xenophobia in post-apartheid South Africa. I contend that any ‘outsider’ (White, Asian or Black African) who lives and trades in South African townships and informal settlements is scapegoated and attacked. I term this phenomenon ‘colour-blind xenophobia’. By proposing this analytical framework and integrating two theoretical perspectives — proximity-based ‘Realistic Conflict Theory (RCT)’ and Neocosmos’ exclusivist citizenship model — I contend that xenophobia in South Africa targets those who are in close proximity to disadvantaged Black South Africans and who are deemed outsiders (e.g., Asian, African even White residents and traders) and reject arguments that describe xenophobia in South Africa as targeting Black African refugees and migrants.

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