Paspalum simplex is a grass distributed throughout the phytogeographic Chaco region in South America from which sexual diploid and apomictic tetraploid races have been reported. We analysed native populations to determine their homogeneity of ploidy level, and the relationship between geographic distribution, ploidy levels, and reproductive systems. The ploidy level was established for 379 plants from 32 wild populations. Tetraploidy and apomixis constitute the most common combination for this species all over the Chaco region. Apomictic hexaploid plants were found associated with 4x populations. Diploids were confined to a small sector of the region. One sexual triploid plant arose from seed harvested in a pure 2x population, and one apomictic 3x plant was found in a mixed 2x-4x population. The results suggest that P. simplex is a core agamic complex characteristic of the Chaco region from which other apomictic polyploid species of the subgenus Anachyris could have evolved.
‘Multiple-use services’ (MUS) takes into account the fact that households use water for both domestic and for productive uses. This paper is the first to determine how managed aquifer recharge (MAR) systems are a form of MUS. Two cases were studied in India and in Kenya. In the Kenyan case, sand dams are the form of MAR, and in India check dams and infiltration ponds of various scales are used. Through observations, interviews, and water quality data, it is possible to describe how the communities access the water from these infrastructures in multiple ways for different uses, according to their water needs and the characteristics of the different access points. MAR involves harvesting rainwater and retaining run-off water into the dry season thus increasing the amount of available water and enabling diversification of water uses. It should therefore be considered as an option by water managers aiming to develop water resources meeting both the domestic and productive needs of communities.
The accumulation of mass from the interaction process that forms the polar ring galaxies is a factor that favors the conditions necessary to trigger nonthermal nuclear activities.. This fact encouraged the chemical analysis of ten polar ring galaxies. In order to verify the presence of an active nucleus in these galaxias
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