Tropical agroecosystems

Liu DL, Christians NE (1994) Isolation and identification of rootinhibiting compounds from corn gluten hydrolysate. J Plant Growth Reg 1 227-230 Luo SM, Lin XL, Zeng RS, Kong CH, Cao PR (1995) Allelopathy of tropical plants in agroecosystem of South China. Ecol Sci 2 114-128... 

Figure 17.16. Correlation plots of organic C functional groups as a fraction of total carbon (in %) identified by C (Is) NEXAFS and 13C NMR spectroscopy of humic substances from native and less disturbed tropical and subtropical agroecosystems [A = 17, P < 0.05 data recalculated from Solomon et al. (2005a, 2007a) and D. Solomon et al. (unpublished data 2007)].

Palm, C.A. Gachengo, C.N. Delve, R.J. Cadisch, G. and K.E. Giller (2001) Organic inputs for soil fertility management in tropical agroecosystems application of an organic-resource database.- Agriculture, Ecosystems and Environment 83, 27-42. 

Department of Organic Plant Production and Agroecosystems Research in the Tropics and Subtropics at the Institute of Crop Science (INK), University of Kassel, Germany... 

Pugalenthi, M., Vadivel, V., Gurumoorthi, P. and Janardhanan, K. (2004) Composative nutritional evaluation of little known legumes, Tamarindus indica, Erythirna indica and Sesbania bispinosa. Tropical and Subtropical Agroecosystems 4, 107-123. 

It can be seen that most areas sensitive to acid deposition are in Southeast China, and that the insensitive is in the Northwest. The sensitive areas, including the catchment of the Changjiang (Yangtze) River and the wide areas to the southward, are warm and rain-abundant. The natural vegetation is the Tropic Rain Forest, Seasonal Rain Forest, and Subtropical Evergreen Forest ecosystems. The dominant soils in these areas are acid Ferralsols, with obvious accumulation of iron and aluminum. These soils can tolerate approximately 0.8-1.6g/m /yr. of sulfur from acid deposition and belong to the intermediate sensitivity class 3. In Northwest China, the climate is semiarid or arid. The predominant ecosystems are Dry Steppe and agroecosystems, with spots of Deciduous Forest or Mixed Forest ecosystems. The soils represented by Xerosol and Alpine types are carbonate-rich and saline. Consequently, they are resistant to acidification. 

Tropical agroecosystems cover a wide range of intensity, including agroforests, intensive plantations of perennials such as coffee, tea and oil palm, annual crops cultivated at all intensities (from slash-and-burn systems with up to 20 years of bush fallow between cropping phases and no external... 

Table 11.2. Application of solution nuclear magnetic resonance spectroscopy to topsoil samples from agroecosystems in the tropics. 

Matenga V.R., Ngongoni N.T., Titterton M., Maasdorp B.V. Mucuna seed as a feed ingredient for small ruminants and effect of ensiling on its nutritive value. Tropical and Subtropical Agroecosystems, 1 97-105 (2003). 

U.S., Canadian, and Australian wheat and U.S. corn) and meat and of the Third World s specialty crop (coffee, cocoa) and tropical fruit harvest are sold abroad. The net trade in feedstuffs alone (mostly cereals, hut also roots, legumes, and oil crops) amounts to between 4 and 7 Mt N/year see Bouwman, A. F., and H. Booij. 1998. Global use and trade of feedstuffs and consequences for the nitrogen cycle. Nutrient Cycling in Agroecosystems 52 261-267. 

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