Pesticide efficacy is improved by surfactants. Increase in the foliar uptake is particularly useful for herbicides, growth regulators and defoliants, because less active compounds are needed, thus decreasing cost and pollution. Therefore, the choice of the adjuvant in an agrochemical formulation is crucial. The surfactants commonly used as adjuvants include anionic, non-ionic, amphoteric and cationic surfactants. This review analyses the role and properties of the new adjuvants for agriculture and the improvement of the ecotoxicity profile of the pesticide formulations in glyphosate formulation.

The interfacial properties of a new family of nonionic surfactants derived from alkyl glucosides were studied. The physicochemical parameters of these dimeric compounds were compared with those of their monomeric counterparts. The effect of the position of the linkage, the anomeric configuration, the spacer functionality, and the spacer type (rigid or flexible) on the behavior of these surfactants was analyzed for a short-chain (butyl) series of compounds. Slight structural variations have a significant influence on their properties. The maximum length of the hydrophobic chains for obtaining gemini surfactants with improved efficiencies compared to those of the starting monomeric alkyl glucosides was estimated.

Glaciers and the periglacial environment in Argentina have been protected by the Law since 2010. This legislation required the development of the first National Glacier Inventory (NGI), which was officially presented in May 2018 and based on satellite images spanning between 2004 and 2016. Here, we present the methods and results of the NGI, summarize the glaciers’ morphological and spatial characteristics, and compare our results to previous regional and global inventories. The NGI reveals an impressive variety of ice masses including rock glaciers, permanent snowfields, mountain and valley glaciers with varying amounts of debris-cover and large outlet glaciers. The Argentinean Andes contain 16 078 ice masses covering an area of 5769 km2 between 200 and 6900 m a.s.l. Comparison of the combined national inventories of Argentina and Chile (~30 000 glaciers and 28 400 km2) with the Randolph Glacier Inventory 6.0 for the Southern Andes (~16 000 glaciers and 29 400 km2), shows that there are large differences in extent and number of glaciers in some sub-regions. The NGI represents an improvement for a better understanding of Argentina's freshwater reservoirs and provides detailed information for the preservation and study of ice masses along 4000 km of the Southern Andes.

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The synthesis and associated structure-activity relationships for gene transfection of a series of spermine-derived cationic gemini surfactants incorporating diamino acid headgroups and either identical (symmetrical) or different (unsymmetrical) lipophilic tailgroups is described. Transfection activity is found to depend critically upon the structural elements present.

Rock glaciers near the Andean mountains of central and northwestern Argentina provide an important supply of water for agriculture, but data on their number, size, geographic distribution and altitudinal range are poorly known. Here, we provide the first detailed rock glacier inventory of the Valles Calchaquíes region of Salta, Argentina, based on 2.5 m x 2.5 m resolution Advanced Land Observing Satellite PRISM (Panchromatic Remote-sensing Instruments for Stereo Mapping) satellite images. Rock glacier outlines were manually digitised and a total of 488 were identified, which cover a total area of c. 59 km 2 . The lower limits of intact and fossil rock glaciers are at c. 4300 m asl and 4100 m asl, respectively. Because rock glaciers are protected by law in Argentina, the inventory provides an important basis for political decision-making about water resources and for further periglacial and environmental studies in this region.