Definition: There is no evidence that the organism produces compounds (allelochemicals) that influence the growth, survival, and reproduction of other organisms.
Definition: The percentage of organic carbon divided by the percentage of total nitrogen in organic material is lower than 23.
Comment: USDA Plants database specifies the organic material as either the above ground biomass of an herbaceous plant or the above ground herbaceous material of a woody plant.
Definition: A porosity quality inhering in a bearer by virtue of the bearer's being incapable of admitting the passage of gas or liquid through pores or interstices.
Definition: A porosity quality inhering in a bearer by virtue of the bearer's being capable of admitting the passage of gas or liquid through pores or interstices. (or, as in fungi, solids such as spores may be admitted through pores in the hymenium, for example)
Definition: A grassland biome is a terrestrial biome which includes, across its entire spatial extent, an unbroken layer of grasses (Gramineae), sedges (Cyperaceae) or rushes (Juncaceae).
Definition: Winter-annual weed segetal and ruderal vegetation of man-made habitats of the Mediterranean, the mild-winter Atlantic seaboards and Macaronesia
Definition: Of plant duration, a plant whose life span ends within one year after germination, e.g. a winter annual germinating in the autumn and flowering in the spring (esp. in Mediterranean climates), approximately synonymous to therophyte, c.f. biennial, ephemeral, perennial, c.f. also of flowering with respect to architecture, hapaxanthic, monocarpic, pleonanthic.
Definition: Of plant duration, a plant whose life span ends within one year after germination, e.g. a winter annual germinating in the autumn and flowering in the spring (esp. in Mediterranean climates), approximately synonymous to therophyte, c.f. biennial, ephemeral, perennial, c.f. also of flowering with respect to architecture, hapaxanthic, monocarpic, pleonanthic.
Definition: Of plant duration, a plant whose life span ends within one year after germination, e.g. a winter annual germinating in the autumn and flowering in the spring (esp. in Mediterranean climates), approximately synonymous to therophyte, c.f. biennial, ephemeral, perennial, c.f. also of flowering with respect to architecture, hapaxanthic, monocarpic, pleonanthic.
Definition: one of three metabolic pathways for carbon fixation in photosynthesis, along with C4 and CAM. This process converts carbon dioxide and ribulose bisphosphate (RuBP, a 5-carbon sugar) into 3-phosphoglycerate through the following reaction:\r\n\r\nCO2 + H2O + RuBP → (2) 3-phosphoglycerate\r\n\r\nThis reaction occurs in all plants as the first step of the Calvin–Benson cycle.
Definition: A terrestrial plant is a plant that grows on or in or from land. Other types of plants are aquatic (living in water), epiphytic (living on trees) and lithophytic (living in or on rocks)
Definition: National Museum of Natural History, Smithsonian Institution (USNM), Washington, District of Columbia, USA.\r\nNMNH and USNM both refer to the National Museum of Natural History. Collections are associated with one or the other acronym. US, the US National Herbarium, is a collection within the National Museum of Natural History. URL for main institutional website, http://www.mnh.si.edu/rc/\r\nURL for institutional specimen catalog, http://collections.mnh.si.edu/
Definition: National Museum of Natural History, Smithsonian Institution (USNM), Washington, District of Columbia, USA.\r\nNMNH and USNM both refer to the National Museum of Natural History. Collections are associated with one or the other acronym. US, the US National Herbarium, is a collection within the National Museum of Natural History. URL for main institutional website, http://www.mnh.si.edu/rc/\r\nURL for institutional specimen catalog, http://collections.mnh.si.edu/