Economical Valuation Of The Erosion Effect In Soil Managemnet Systems Employing The Replacement Cost Method [valoração Econômica Do Efeito Da Erosão Em Sistemas De Manejo Do Solo Empregando O Método Custo De Reposição]

The accelerate soil erosion constitutes an important process of agricultural land quality degradation. Often, only the physical soil losses are assessed, neglecting the economical effects of those losses, which could be estimated by applying methods of economical valuation. This work intended to apply the Replacement Cost method to evaluate economically the nutrient losses by erosion from a Rhodic Hapludox. Data concerning soil and nutrient losses were analyzed from two experiments performed in Campinas (SP. In Experiment I (1990-1996), eight treatments were tested, one for each experimental parcel, and the repetitions were the years. In Experiment II (2003-2005), two treatments were tested with four replications, for two growing seasons. In Experiment I, significant differences between treatments occurred in relation to soil and nutrient losses. The "no-tillage" was the best treatment to control the soil erosion losses, whereas the "plowing downhill" was the worst treatment. Apparently, the soil erosion losses didn't affect the corn yields, because differences between treatments were not statistically significant. Also, no significant differences were found between treatments in relation to the costs of nutrient replacement. The differences between treatments of Experiment II were not significant for any analyzed attribute, maybe due to a residual effect from treatments of Experiment I (previous). The Replacement Cost method can be applied as an indicator on the evaluation of the sustainability of soil management systems. However, in long-term experiments, the annual variation of prices of fertilizers and labor could mask the effects of the treatment themselves.701113121Blevins, R.L., Frye, W.W., Conservation tillage: An ecological approach to soil management (1993) Advances in Agronomy, 51, pp. 33-78Cassol, E.A., de Lima, V.S., Erosão em entressulcos sob diferentes tipos de preparo e manejo do solo (2003) Pesquisa Agropecuária Brasileira, 38, pp. 117-124Castro, O.M., Lombardi, N.F., Vieira, S.R., Dechen, S.C.F., Sistemas convencionais e reduzidos de preparo do solo e as perdas por erosão (1986) Revista Brasileira De Ciência Do Solo, 10, pp. 167-171Dixon, J.A., Hufschmidt, M.M., (1986) Economic Valuation for the Environment: A Case Study Workbook, p. 203. , Baltimore: The Johns Hopkins University PressEltz, F.L.F., Mehl, H.U., Reichert, J.M., Perdas de solo e água em entressulcos em um Argissolo Vermelho-Amarelo submetido a quatro padrões de chuva (2001) Revista Brasileira De Ciência Do Solo, 25, pp. 485-494Gardner, K., Barrows, R., The impact of soil conservation investments on land prices (1985) American Journal of Agricultural Economics, 67, pp. 943-947Hertzler, G., Ibanez-Meier, C.A., Jolly, R.W., User costs of soil erosion and their effect on agricultural land prices: Costate variables and capitalized Hamiltonians (1985) American Journal of Agricultural Economics, 67, pp. 948-953Hufschmidt, M.M., James, E., Meister, A.D., Bower, B.T., Dixon, J.A., (1983) Environment, Natural Systems and Development: An Economic Valuation Guide, p. 338. , Baltimore: The Johns Hopkins University PressKing, D.A., Sinden, J.A., Influence of soil conservation on farm land values (1988) Land Economics, 64, pp. 242-255Kitamura, P.C., Lanzer, E.A., Adams, R.I., Avaliação econômica de sistemas conservacionistas no uso de solos agrícolas: O caso do binômio trigo-soja no Rio Grande do Sul (1982) Revista De Economia E Sociologia Rural, 20, pp. 104-124Kooten, G.C., Weisensel, W.P., Chilanthammit, D., Valuing trade-offs between net returns and stewardship practices: The case of soil conservation in Saskatchewan (1990) American Journal of Agricultural Economics, 72, pp. 104-113Lal, R., Soil erosion and land degradation: The global risks (1990) Advances in Soil Science, 11, pp. 129-172Marques, J.F., Custos da erosão do solo em razão dos seus efeitos internos e externos à área de produção agrícola (1998) Revista De Economia E Sociologia Rural, 36, pp. 61-79Melo Filho, J.F., Silva, J.R.C., Erosão, teor de água no Solo e produtividade do milho em plantio direto e preparo convencional de um Podzólico Vermelho-Amarelo no Ceará (1993) Revista Brasileira De Ciência Do Solo, 17, pp. 291-297Mutchler, C.K., Murphree, C.E., McGregor, K.C., (1994) Laboratory and Field Plots for Erosion Research, pp. 1-9. , In: LAL, R. Soil Erosion Research Methods. 2.ed, Delray Beach: St. Lucie Press, Soil and Water Conservation SocietyPiearce, F.J., Dowdy, R.H., Larson, W.E., Graham, W.A.P., Soil productivity in the Corn Belt: An assessment of erosion's long-terms effects (1984) Journal of Soil and Water Conservation, 39, pp. 131-136Pierce, F.J., Lal, R., (1994) Monitoring the Impact of Soil Erosion on Crop Productivity, pp. 235-263. , In: LAL, R. (Ed.) Soil Erosion Research Methods. 2.ed. Delray Beach, FL, St. Lucie Press, Soil and Water Conservation ServicePope III, C.A., Bhides, S., Heady, E.O., Economics of conservation tillage in Iowa (1983) Journal of Soil and Water Conservation, 38, pp. 370-373Ramalho, M.A.P., Ferreira, D.F., Oliveira, A.C., (2000) Experimentação Em Genética E Melhoramento De Plantas, p. 326. , Lavras: UFLARodrigues, W., Valoração econômica dos impactos ambientais de tecnologias de plantio em região de Cerrados (2005) Revista De Economia E Sociologia Rural, 43, pp. 135-153Sparovek, G., Teramoto, E.R., Toreta, D.M., Rochele, T.C.P., Shayer, E.P.M., Erosão simulada e a produtividade da cultura do milho (1991) Revista Brasileira De Ciência Do Solo, 15, pp. 363-368Swanson, E.R., Maccallum, D.E., Income effects of rainfall erosion control (1969) Journal of Soil and Water Conservation, 24, pp. 56-59Thomé Jr., J.B., (1997) Manual Para Interpretação De Análise De Solo, p. 247. , Guaíba: Livraria e Editora AgropecuáriaXu, F., Prato, T., On site erosion damages in Missouri corn production (1995) Journal of Soil and Water Conservation, 50, pp. 312-316Wang, X.B., Cai, D.X., Hoogmed, W.B., Oenema, O., Perdok, U.D., Potential effect of Conservation Tillage on Sustainable Land Use: A Review of Global Long-Term Studies (2006) Pedosphere, 16, pp. 587-59

Impacto técnico e econômico das perdas de solo e nutrientes por erosão no cultivo da cana-de-açúcar Economic and technical impact in soil and nutrient loss through erosion in the cultivation of sugar can

O objetivo geral foi demonstrar o impacto técnico e econômico das perdas de solo e nutrientes por erosão no cultivo da cana-de-açúcar. Propôs-se avaliar as perdas de nutrientes por erosão (P, K, Ca e Mg), o custo de reposição de nutrientes e o de produção da cana em dois sistemas de colheita (cana crua e queimada) em Catanduva - SP, em área de 100 ha para cada sistema, formadas e colhidas no mesmo período (2002 a 2007), com similaridade quanto ao tipo de solo, variedade, topografia e numero de cortes. A metodologia baseou-se na equação universal da perda de solos e teoria dos custos de produção e de reposição de nutrientes. A maior perda de solo e de nutrientes por erosão ocorreu nas áreas de cana queimada; a cana queimada (corte manual), na média dos cinco cortes, perde 48,82% por hectare a mais de solo, 56,45 % de potássio (K) e 60,78 % de fósforo (P) do que a cana crua (corte mecanizado); o custo de reposição de nutrientes, em média, na cana queimada (R$33,92 ha-1 ano-1), foi superior ao da cana crua (R$ 21,12 ha-1 ano-1); a cana crua apresentou menor custo de produção (R$29,60 Mg-1) quando comparado à cana queimada (R$ 32,71 Mg-1); a cana crua apresentou maior retorno médio (R$5,70 Mg-1ano-1) com relação à cana queimada (R$ 2,59 Mg-1).<br>The general objective was to show the economic and technical impact in soil and nutrient loss through erosion in the cultivation of sugar cane. It was specifically to evaluate the nutrient loss through erosion (P, K, Ca and Mg), the cost of replacing the nutrients and the production of sugar cane in two harvesting systems (raw and burned sugar cane) in Catanduva, state of São Paulo, Brazil. An area of 100 ha was studied for each system, formed and harvested in the same period (2002 and 2007), with similarities in the type of soil, variety, topography, and the number of cuts. The methodology was based on the universal equation of soil loss and the theory of production costs and the replacement of nutrients. The greatest loss of soil nutrients and erosion occurred in the areas of the burned sugar cane; the burned sugar cane (cut by hand), the average of five cuts, losses 48.82% per hectare of land, 56.45% of potassium (K) and 60.78% of phosphorus (P) than the raw sugarcane (mechanical harvesting), the replacement cost of nutrients, on average, by the burned cane (R$33.92 ha-1 year-1) was higher that the raw sugarcane (R$ 21.12 ha-1 year-1), the raw sugar cane had lower production cost (R$29.60 Mg-1) compared to the burned sugar cane (R$ 32.71 Mg-1) ; the raw sugar cane had a higher average return (R$5.70 Mg-1year-1) with respect to the burned sugar cane (R$ 2.59 Mg-1)

Valuation and assessment of soil erosion costs

Soil is an essential natural resource for humans and an important part of the environment. However, soil is often used and managed inappropriately, causing its erosion and degradation, with concomitantly negative social, political and economic impacts. This study aimed to discuss sustainable development; and losses and problems caused by soil erosion, and to suggest a model for assessing erosion costs. The relevance of economic models for costing soil erosion is stressed. Based on an economic theory, it presents a procedure for assessing economic costs of soil erosion, centered on the on-site and off-site costs that are generated. The physical processes of soil erosion are described and their economic effects reviewed, drawing on theoretical and empirical sources. Limited data and information is available on the economic losses resulting from erosion, which hampers assessment and valuation