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- ItemOpen AccessA Global Systematic Review of Improving Crop Model Estimations by Assimilating Remote Sensing Data: Implications for Small-Scale Agricultural Systems(Multidisciplinary Digital Publishing Institute, 2023-08-17) Dlamini, Luleka; Crespo, Olivier; van Dam, Jos; Kooistra, LammertThere is a growing effort to use access to remote sensing data (RS) in conjunction with crop model simulation capability to improve the accuracy of crop growth and yield estimates. This is critical for sustainable agricultural management and food security, especially in farming communities with limited resources and data. Therefore, the objective of this study was to provide a systematic review of research on data assimilation and summarize how its application varies by country, crop, and farming systems. In addition, we highlight the implications of using process-based crop models (PBCMs) and data assimilation in small-scale farming systems. Using a strict search term, we searched the Scopus and Web of Science databases and found 497 potential publications. After screening for relevance using predefined inclusion and exclusion criteria, 123 publications were included in the final review. Our results show increasing global interest in RS data assimilation approaches; however, 81% of the studies were from countries with relatively high levels of agricultural production, technology, and innovation. There is increasing development of crop models, availability of RS data sources, and characterization of crop parameters assimilated into PBCMs. Most studies used recalibration or updating methods to mainly incorporate remotely sensed leaf area index from MODIS or Landsat into the WOrld FOod STudies (WOFOST) model to improve yield estimates for staple crops in large-scale and irrigated farming systems. However, these methods cannot compensate for the uncertainties in RS data and crop models. We concluded that further research on data assimilation using newly available high-resolution RS datasets, such as Sentinel-2, should be conducted to significantly improve simulations of rare crops and small-scale rainfed farming systems. This is critical for informing local crop management decisions to improve policy and food security assessments.
- ItemOpen AccessDiversity and Ranking of ENSO Impacts along the Eastern Seaboard of Subtropical Southern Africa(Multidisciplinary Digital Publishing Institute, 2023-06-17) Blamey, Ross C.; Reason, Chris J. C.El Nino–Southern Oscillation (ENSO) is the dominant mode of interannual climate variability over southern Africa during the summer half of the year. It is widely accepted that El Nino (La Nina) core summers (December–February) are typically warmer and drier (cooler and wetter) than average over the region. Although it is recognized that the ENSO impacts are nonlinear and not all events result in the expected impact, little or no work has been carried out to systematically explore the diversity and ranking of these impacts. Here, parameter-space bubble plots involving various rainfall and temperature metrics are used to study how such impacts vary over the eastern seaboard of subtropical southern Africa to determine the ENSO events with the strongest impacts, and to identify the most anomalous ENSO cases. Comparison of neutral summers experiencing the strongest droughts/floods with ENSO impacts is also performed. These metrics are designed to be applicable to the interests of farmers and other user groups. It is found that 1987/1988 (2017/2018) was the most unusual El Nino (La Nina) and neutral 1981/1982 had a severe drought, worse than occurs during most El Ninos. These unusual cases are explained in terms of regional circulation and SST anomalies. Implications of the results for seasonal forecasting and for farmers are discussed.
- ItemOpen Access‘Follow the Water’: Microbial Water Acquisition in Desert Soils(2023-06-27) Cowan, Don A; Cary, S. Craig; DiRuggiero, Jocelyne; Eckardt, Frank; Ferrari, Belinda; Hopkins, David W.; Lebre, Pedro H.; Maggs-Kölling, Gillian; Pointing, Stephen B.; Ramond, Jean-Baptiste; Tribbia, Dana; Warren-Rhodes, KimberleyWater availability is the dominant driver of microbial community structure and function in desert soils. However, these habitats typically only receive very infrequent large-scale water inputs (e.g., from precipitation and/or run-off). In light of recent studies, the paradigm that desert soil microorganisms are largely dormant under xeric conditions is questionable. Gene expression profiling of microbial communities in desert soils suggests that many microbial taxa retain some metabolic functionality, even under severely xeric conditions. It, therefore, follows that other, less obvious sources of water may sustain the microbial cellular and community functionality in desert soil niches. Such sources include a range of precipitation and condensation processes, including rainfall, snow, dew, fog, and nocturnal distillation, all of which may vary quantitatively depending on the location and geomorphological characteristics of the desert ecosystem. Other more obscure sources of bioavailable water may include groundwater-derived water vapour, hydrated minerals, and metabolic hydro-genesis. Here, we explore the possible sources of bioavailable water in the context of microbial survival and function in xeric desert soils. With global climate change projected to have profound effects on both hot and cold deserts, we also explore the potential impacts of climate-induced changes in water availability on soil microbiomes in these extreme environments.
- ItemOpen AccessOn the Fence: The Impact of Education on Support for Electric Fencing to Prevent Conflict between Humans and Baboons in Kommetjie, South Africa(Multidisciplinary Digital Publishing Institute, 2023-06-27) Walsh, Debbie; O’Riain, M. Justin; Nattrass, Nicoli; Gaynor, DavidFew studies test whether education can help increase support for wildlife management interventions. This mixed methods study sought to test the importance of educating a community on the use of a baboon-proof electric fence to mitigate negative interactions between humans and Chacma baboons (Papio ursinus) in a residential suburb of the City of Cape Town, South Africa. An educational video on the welfare, conservation and lifestyle benefits of a baboon-proof electric fence was included in a short online survey. The positioning of the video within the survey was randomised either to fall before or after questions probing the level of support for an electric fence. The results showed that watching the video before most survey questions increased the average marginal probability of supporting an electric fence by 15 percentage points. The study also explored whether the educational video could change people’s minds. Those who saw the video towards the end of the survey were questioned again about the electric fence. Many changed their minds after watching the video, with support for the fence increasing from 36% to 50%. Of these respondents, the results show that being female raised the average marginal probability of someone changing their mind in favour of supporting the fence by 19%. Qualitative analysis revealed that support for or against the fence was multi-layered and that costs and concern for baboons were not the only relevant factors influencing people’s choices. Conservation often needs to change people’s behaviours. We need to know what interventions are effective. We show in the real world that an educational video can be effective and can moderately change people’s opinions and that women are more likely to change their position in light of the facts than men. This study contributes to the emerging literature on the importance of education in managing conservation conflicts and the need for evidence-based interventions.
- ItemOpen AccessSalts of S-(+)-Ibuprofen Formed via Its Reaction with the Antifibrinolytic Agents Aminocaproic Acid and Tranexamic Acid: Synthesis and Characterization(Multidisciplinary Digital Publishing Institute, 2023-08-08) Frösler, Hannah M.; Ramulumo, Humbelani S.; Edmonds-Smith, Cesarina; Caira, Mino R.The paucity of multi-component compounds containing the non-steroidal anti-inflammatory drug (NSAID) S-(+)-ibuprofen (S-IBU) in combination with other drugs prompted the present study, which describes 1:1 salts of this active pharmaceutical ingredient (API) with the two most widely used antifibrinolytic APIs, namely 6-aminohexanoic acid (aminocaproic acid, ACA) and tranexamic acid (TXA), which are zwitterions in the solid state. Since NSAIDs are known to cause adverse side effects such as gastrointestinal ulceration, the presence of ACA and TXA in the salts with S-(+)-ibuprofen might counter these effects via their ability to prevent excessive bleeding. The salts were prepared by both the liquid-assisted grinding method and co-precipitation and were characterized by X-ray powder diffraction and single-crystal X-ray diffraction, thermal analysis, Fourier transform infrared spectroscopy, and solubility measurements. The X-ray analyses revealed a high degree of isostructurality, both at the level of their respective asymmetric units and in their extended crystal structures, with charge-assisted hydrogen bonds of the type N-H...O and O-H.. O featuring prominently. The thermal analysis indicated that both salts had significantly higher thermal stability than S-(+)-ibuprofen. Solubility measurements in a simulated biological medium showed insignificant changes in the solubility of S-(+)-ibuprofen when tested in the form of the salts (S-IBU) (TXA).