caa a22 4500 463209176 CHVBK 20180405153135.0 cr unu---uuuuu 170326e20070901xx s 000 0 eng 10.1007/s10705-007-9095-5 doi (NATIONALLICENCE)springer-10.1007/s10705-007-9095-5 Benefits of organic residues and chemical fertilizer to productivity of rain-fed lowland rice and to soil nutrient balances [Elektronische Daten] [Bruce Linquist, Vongvilay Phengsouvanna, Pheng Sengxue] Low yields and high risk characterize many rain-fed lowland rice environments, including those in Laos. Drought and fluctuating soil-water conditions (from aerobic to anaerobic states) can limit productivity and the efficient use of applied nutrients. Although addition of organic matter may improve the efficiency of fertilizer use, on-farm residues, for example farmyard manure (FYM), rice straw and rice hulls, are, currently, poorly utilized in these systems. Single and multi-year experiments were designed to evaluate the effect of these residues on rice productivity and efficiency of fertilizer use at four sites. Rice yield without fertilizer but with addition of residues ranged from 1.1 to 1.7tha−1 across sites and years. In response to fertilizer, yields increased on average by 1.4tha−1. For all sites and years there was a significant response of yield to organic residues applied without fertilizer, with responses ranging from 0.2 to 1.4tha−1. In 58% of cases there was no residue×fertilizer interaction (benefits of residues when applied with fertilizer were additive). In 38 and 4% of cases the interaction was negative (no response to residues if fertilizer was already applied) or positive (synergistic), respectively. In the multi-year studies, the type of interaction varied between years, suggesting that seasonal events, rather than soil type, determine the type of interaction. The greatest benefits of applying organic and chemical fertilizers together were observed in years when soil-water conditions were unfavorable (fluctuating anaerobic-aerobic conditions). The long-term effects of these different management strategies on soil nutrient balances suggest that N, P, and K balances were maintained as a result of balanced commercial fertilizer management but that addition of residues further enhanced these balances. All residues, when applied alone, resulted in positive soil Si balances; only with FYM were long-term N, P, and K balances maintained or positive, however. For resource-poor farmers, applying on-farm residues can be a sustainable approach to increasing productivity. Springer Science+Business Media B.V., 2007 Fertility management nationallicence Interactions nationallicence Nitrogen nationallicence Nutrient-use efficiency nationallicence Organic nationallicence Phosphorus nationallicence Potassium nationallicence Rain-fed lowland rice nationallicence Residue nationallicence Silica nationallicence Synergistic benefits nationallicence Linquist Bruce Department of Plant Science, University of California, Davis, USA aut Phengsouvanna Vongvilay Provincial Agriculture and Forestry Office, Champassak, Lao PDR aut Sengxue Pheng National Agriculture and Forestry Research Institute, Vientiane, Lao PDR aut Nutrient Cycling in Agroecosystems Kluwer Academic Publishers 79/1(2007-09-01), 59-72 1385-1314 79:1<59 2007 79 10705 https://doi.org/10.1007/s10705-007-9095-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10705-007-9095-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Linquist Bruce Department of Plant Science, University of California, Davis, USA aut NATIONALLICENCE 700 1- Phengsouvanna Vongvilay Provincial Agriculture and Forestry Office, Champassak, Lao PDR aut NATIONALLICENCE 700 1- Sengxue Pheng National Agriculture and Forestry Research Institute, Vientiane, Lao PDR aut NATIONALLICENCE 773 0- Nutrient Cycling in Agroecosystems Kluwer Academic Publishers 79/1(2007-09-01), 59-72 1385-1314 79:1<59 2007 79 10705 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer