Ulises Reno

At the beginning of 2024, Argentina was characterised by an unfavourable socio-economic context characterised by poverty, inflation and a national declaration of a food emergency. Recognising that these are complex challenges requiring multifaceted solutions, this chapter examines the diverse capacities of urban gardens to address not only the nutritional dimension but also their contributions to economic, social, urban and environmental aspects. In Argentina, public policies have been implemented to stimulate urban agriculture and gardening practices as a response to the mentioned challenges. The Argentine Plan Against Hunger (PACH) and the ProHuerta Program exemplify national-level policies, while the Urban Agriculture Program (PAU) in Rosario stands out as a local initiative. This chapter highlights the main characteristics of these programmes and, looking to the future, proposes synergies to enhance their integration and consolidation. However, several barriers are highlighted that must be overcome, considering the shared responsibilities at different levels. Despite the recognition of urban gardening as a strategy that addresses crises, the existence and future forms of public policies supporting urban gardens remain uncertain amid recent national political changes. This research provides valuable evidence to re-evaluate the issues developed in the coming years in Argentina.

The COVID-19 pandemic affected human life at every level. In this study, we analyzed genetic markers (N and ORF1ab, RNA genes) of SARS-CoV-2 in domestic wastewaters (DWW) in San Justo City (Santa Fe, Argentina), using reverse transcription-quantitative real-time PCR. Out of the 30 analyzed samples, 30% were positive for SARS-CoV-2 RNA. Of the total positive samples, 77% correspond to untreated DWW, 23% to pre-chlorination, and no SARS-CoV-2 RNA was registered at the post-chlorination sampling site. The viral loads of N and OFR1ab genes decreased significantly along the treatment process, and the increase in the number of viral copies of the N gene could anticipate, by 6 days, the number of clinical cases in the population. The concentration of chlorine recommended by the WHO (≥ 0.5 mg L⁻¹ after at least 30 min of contact time at pH 8.0) successfully removed SARS-CoV-2 RNA from DWW. The efficiency of wastewater-based epidemiology (WBE) confirms the need to control and increase DWW treatment systems on a regional and global scale. This work could contribute to building a network for WBE to monitor SARS-CoV-2 in wastewaters during the pandemic waves and the epidemic remission phase. Graphical abstract

The general objective of this work is to experimentally assess the effects of acute glyphosate pollution on two freshwater cladoceran species (Daphnia magna and Ceriodaphnia dubia) and to use this information to predict the population dynamics and the potential for recovery of exposed organisms. Five to six concentrations of four formulations of glyphosate (4-Gly) (Eskoba^®, Panzer Gold^®, Roundup Ultramax^® and Sulfosato Touchdown^®) were evaluated in both cladoceran species through acute tests and 15-day recovery tests in order to estimate the population dynamics of microcrustaceans. The endpoints of the recovery test were: survival, growth (number of molts), fecundity, and the intrinsic population growth rate (r). A matrix population model (MPM) was applied to r of the survivor individuals of the acute tests, followed by a Monte Carlo simulation study. Among the 4-Gly tested, Sulfosato Touchdown^® was the one that showed higher toxicity, and C. dubia was the most sensitive species. The Monte Carlo simulation study showed an average value of λ always D. magna, indicating that its populations would not be able to survive under natural environmental conditions after an acute Gly exposure between 0.25 and 35 a.e. mg L⁻¹. The average value of λ for C. dubia was also ®: 1.30 and 1.20 for 1.21 and 2.5 mg a.e. L⁻¹,respectively. The combined methodology—recovery tests and the later analysis through MPM with a Monte Carlo simulation study—is proposed to integrate key demographic parameters and predict the possible fate of microcrustacean populations after being exposed to acute 4-Gly contamination events.

: This study analyzed the acute effects of a glyphosate‐based herbicide (Eskoba®) on the microalgae Chlorella vulgaris, the cladoceran Simocephalus vetulus, and the copepod Notodiaptomus conifer, and evaluated the recovery ability of the surviving microcrustaceans. Survival, age of first reproduction, and fecundity were used as endpoints for S. vetulus, while survival and time to reach the adult stage were used as endpoints for N. conifer. The registered order of sensitivity was S. vetulus (48‐hour effective concentration [EC₅₀]: 21 mg/L) > C. vulgaris (72‐hour EC₅₀: 58.59 mg/ L) > N. conifer (48‐hour EC₅₀: 95 mg/L). Despite the growth of C. vulgaris stimulated after 24 hours of exposure to the commercial formulation of glyphosate Eskoba®, it was inhibited after 48 hours by all the concentrations tested. In postexposure experiments, microcrustaceans reduced their life expectancy, S. vetulus decreased its fertility, and N. conifer inhibited its sexual maturity. In summary, it was demonstrated that these species lost their recovery ability.

Chronic toxicity tests were conducted to assess the effect of Cu, Cr and Pb on Moinodaphnia macleayi and Ceriodaphnia dubia -two cladoceran species from the Argentinian Fluvial Littoral Zone (AFLZ)- and Daphnia magna -an holarctic species-. The specimens were exposed to three concentrations of each metal. As endpoints, the number of living and dead organisms, molts, neonates released, and the age of first reproduction were recorded. Chronic assays showed that Cu significantly affected the analyzed life history traits in the three species. The lowest Pb and Cr concentrations did not affect survival, molting or fecundity in D. magna. Conversely, in M. macleayi and C. dubia, survival, molting and fecundity showed highly significant differences in all the concentrations tested compared to control assay. The present study stresses the importance of using biological parameters as bioindicators, as well as the study species from the Southern Hemisphere to assess metal pollution.