Acanthaceae are among the most taxonomically diverse, geographically widespread, and morphologically and ecologically variable lineages of flowering plants. Most modern workers have estimated more than 4000 species and potentially more than 5000 species worldwide, thus placing Acanthaceae among the 12 or so most diverse families of angiosperms. This diversity is marked by exceptional morphological variation, particularly with respect to floral forms, growth forms, and pollen types. (Manzitto‐Tripp, Erin & Darbyshire, Iain & Daniel, T. & Kiel, Carrie & McDade, Lucinda. (2021). Revised classification of Acanthaceae and worldwide dichotomous keys. TAXON. 71. 10.1002/tax.12600.)
Share cropping is a system of agricultural production where a landowner allows a share cropper to use the land in return for a share of the crop produced on the land. Share cropping covers a wide range of different situations and types of agreement. (FAO. 2003. Multilingual Thesaurus on Land Tenure. https://openknowledge.fao.org/handle/20.500.14283/x2038e)
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. (Wikipedia, 2024. Sharks. https://en.wikipedia.org/wiki/Shark)
A tool consisting of two blades with bevel edges, connected by a pivot, used for cutting cloth, or for removing the fleece from sheep etc. (Wiktionary. 2025. Shears. https://en.wiktionary.org/wiki/shears)
Sheep are domesticated animals of the species Ovis aries kept in flocks mainly for their milk, wool or meat. (Eurostat, 2023. Sheep. https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Glossary:Sheep)
A sheep dog or sheepdog is generally a dog or breed of dogs historically used in connection with the raising of sheep. These include livestock guardian dogs used to guard sheep and other livestock and herding dogs used to move, manage and control sheep and other livestock. (Wikipedia, 2024. Sheep dog https://en.wikipedia.org/wiki/Sheep_dog)
Precipitation having a pH below 5.6 due to high concentrations of sulphate, nitrate, ammonium or other anions. (FAO. 2008. Glossary of aquaculture. https://openknowledge.fao.org/handle/20.500.14283/a1555m)
Shellfish is a colloquial and fisheries term for exoskeleton-bearing aquatic invertebrates used as food, including various species of molluscs, crustaceans, and echinoderms. (https://en.wikipedia.org/wiki/Shellfish)
Note
Useful aquatic animals having a shell or shell-like exoskeleton such as molluscs or crustaceans
Farming practice whereby a particular piece of land is cultivated for some years and then abandoned for a period sufficient to restore its fertility by natural vegetative growth before being recultivated. (FAO. 2017. World Programme for the Census of Agriculture 2020. Volume I Programme, concepts and definitions. https://openknowledge.fao.org/handle/20.500.14283/i4913e)
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Shifting cultivation is also known as “slash and burn” or “swidden cultivation” and by a variety of local names specific to each place in which it is practiced.
Charcoal that has been treated to remove hydrocarbons and to increase its adsorptive properties. It acts by condensing and holding a gas or solute onto its surface; thus inhibitory substances in nutrient medium may be adsorbed to charcoal included in the medium. (http://www.fao.org/biotech/biotech-glossary/en/)
