Ecosystem, rice

EXAMPLES AND APPLICATIONS The Rapid Increase in C4 Ecosystems (RICE)... 

Figure 8 summarizes the work of Cerling et al. (1997) on the of fossil herbivore teeth from 20 Ma to the present, emphasizing equids and proboscideans, which consume C4 plants if available. Clearly C4 plants must have been rare on Earth before 8 Ma, as herbivore 5 C values are all lower than -7%o and all but one are lower than -8%o. Of course, if C3 plants had 5 C values of -24 to -26%o, then a small dietary component of C4 may have been present since 14-19 Ma (Fig. 8 Morgan et al. 1994). However, by 6-8 Ma, herbivores in Pakistan, Africa, South America, and southern North America show a significant C4 dietary component, indicating a Rapid Increase in C4 Ecosystems (RICE )...

Tejada AW, Varca LM, Calumpang SMP, et al. 1997. Fate of pesticides in a model rice paddy ecosystem. In Environ Behav Crop Prot Chem Proc Int Symp Use Nucl Relat Tech Stud Environ Behav Crop Prot Chem 1996, Int Atom Energy Agency Vienna, Austria pp. 265-278. 

Methane emissions from any ecosystem, particularly a rice agroecosystem (Figure 1), are governed by the magnitude and balance of microbial CH4 production (methanogenesis) and oxidation (methanotrophy), which occur by separate microbial communities. The two groups... 

Pastor D, Sanpera C, Gonzalez-Solis J, Ruiz X, Albaiges J (2004) Factors affecting the organochlorine pollutant load in biota of a rice field ecosystem (Ebro delta, NE Spain). Chemosphere 55(4) 567-576... 

The species dig holes at the bottom and slopes of lakes and canals, causing severe impacts on invaded ecosystems. In the Ebro River, the crayfish is considered responsible for the disappearance of native fauna such as newts, frogs, and the autochthonous crayfish. Furthermore, it affects economically the rice crops in the Delta [53]. 

Rice, C.D., and Arkoosh, M.R., Immunological indicators of environmental stress and disease susceptibility in fishes, in Biological Indicators of Stress in Aquatic Ecosystem Stress, Adams, S.M., Ed., American Fisheries Society Publications, Bethesda, 2002, 187. 

Tomizawa L. 1980. Biological accumulation of pesticides in an ecosystem-evaluation of biodegradability and ecological magnification of rice pesticides by a model ecosystem. Japanese Agricultural Research Quarterly 14 143-149. 

Table 1.2 Rice ecosystems in the main rice-producing countries in Asia...

Upland. Grown in level to steeply sloping fields that are rarely flooded. No effort is made to impound water as for other rice ecosystems. Crop is direct seeded on ploughed dry soil or dibbled in wet, non-puddled soil. 

Rice ecosystem-specific emission factors (Neue and Sass, 1998) 30-50... 

Rice can also be an indirect source of N2O (and NO) emissions via deposition of volatilized ammonia on natural ecosystems, particularly wet tropical forests, which are one of the main natural sources of N2O (Table 8.4a). 

De Datta SK. 1995. Nitrogen transformations in wetland rice ecosystems. Fertiliser Research 42 193-203. 

Roger PA. 1996. Biology and Management of the Eloodwater Ecosystem in Ricefields. Manila International Rice Research Institute. 

Wassmann R, Lantin RS, Neue HU, eds. 2000b. Methane Emissions from Major Rice Ecosystems in Asia. Dordrecht Kluwer. 

MacLean, R.H., Litsinger, J.A., Moody, K., Watson, A.K. and Libetario, E.M. 2003. Impact of Gliricidia sepium and Cassia spectabilis hedgerows on weeds and insect pests of upland rice. Agriculture, Ecosystems and Environment 94(3) 275-288. 

Sharma R (2001) Impact of solar UV-B on tropical ecosystems and agriculture. Case study effect of UV-B on rice. Proceedings of Seawpit98 and Seawpit2000 1 92. Available at http //phototropism.tripod.com/UV-B.pdf. Last visited 18 March 2008... 

Kanrar, B., Ghosh, T., Pramanik, S.K., Dutta, S., Bhattacharyya, A., and Dhuri, A.V., Degradation dynamics and persistence of imidacloprid in a rice ecosystem under West Bengal climate conditions, Bull. Environ. Contam. Toxicol., 77, 631, 2006. 

A.W. Tejada, L.M. Varca, S.M.F. Calumpang, C.M. Bajet, M.J.B. Medina, Fate of Pesticides in a Model Rice Paddy Ecosystem, in Proceedings of a Symposium Environmental Behavior of Crop Protection Chemicals, IAEA-SM-343/33, Viena, Austria, 1997, pp. 265-278. 

Harrison, F.L. and Rice, D.W., Jr. Copper sensitivity of adult Pacific oysters, in Thorp, J.H., III, and Gibbons, J.W., ed., S3rmp. Energy and Environmental Stress in Aquatic Ecosystems," (in press). 

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