Carlos Alberto de Sousa Rosado
Maria José Teixeira Ribeiro
Professors, Social Sciences Department
Escola Superior de Agricultura, Mossoró
Introduction
Since its introduction in the early 1940's, Prosopis juliflora has been praised as one of the most important xerophytic species for the Brazilian semi-arid Northeast. However, research on the species is still inconclusive, in general terms, regarding the technical parameters for cultivation and production.
The difficulties for estimating the costs of establishing/maintaining P. juliflora plantations and their possible economic returns result from the uncertainties concerning technical parameters (spacing, pruning, fertilizing, productivity, etc.). These may lead to wrong estimates which, in turn, compound the errors commonly found in this type of economic analysis, giving rise to wrong budgeting and inadequate product or production estimates.
Material and Methods
Plantation technical coefficients and expected production parameters were taken from emater-pe (1978), deriving Table 1 from these values. Despite the lack of conclusive research on these coefficients for P. juliflora, the parameters used are probably close to reality, as they stem from experiences with the establishment of other tree crops. The greater risks for error in the estimates concern spacing and the possible pruning. These errors will not alter significantly plantation establishment costs, but they will surely reflect on the productivity and useful life of the plantation and may lead to wrong revenue estimates.
Production factor costs were surveyed in the western section of Rio Grande do Norte and correspond to the mean values found at the city of Mossoró and its area of influence.
Land cost corresponds to the price of 1 hectare of low-fertility soils. The land preparation cost (uprooting/felling, stump removal, burning and clearing) represents the outlays at going rates, minus the value of the biomass converted into stakes or charcoal. The plant cover considered was shrubs.
Daily wages correspond to the region's going rates, and the cost of the remaining inputs was quoted directly at commercial establishments in Mossoró.
From the costs and technical coefficients, activity flow, costs and revenues for 20 years were derived.
The economic evaluation was based on net cash flow present value, updated with a 12% discount rate per annum, as well as on the internal return rate derived; on pay back, or time span necessary for the positive revenues to cover the initial investments, and on the cost/benefit rate.
The productivity rate used for calculating the gross yield of 1 hectare of P. juliflora was that indicated by the emater (1978) production system. Production per hectare is 500 kg of pods in the third year after planting; 1,000 kg in the fourth year; 1,500 kg in the fifth year, and 3,000 kg from the 6th to the 20th year.
Results
As no accurate estimates were available, the investment's residual value was broken down into land cost, improvement cost (clearing and fences), remaining firewood from the P. juliflora forests and the probable enrichment of the soil through nitrogen fixation.
The benefit/cost ratio with updated cash flow discounted at a 12 percent annual rate for a 20-year period was 2.32, indicating a net return of 1.32 for each monetary unit invested in the activity.
The estimated internal return rate was 21.5, indicating that the investment, at year 20, will have revenue flow equated to expense flow; capital opportunity cost was 21.5 percent per annum.
The simple pay-back method indicates that the investment will show positive returns as of the seventh year after plantation establishment.
Conclusion
The economic findings arrived at in this study indicate that P. juliflora planting is competitive with other short-cycle crops traditional in the semi-arid region.
The economic yield is higher than that for macassar bean, corn and arboreal cotton, according to the values found by Porto Filho (1981).
It is comparable to herbal cotton, but entails lower risk.
The economic returns found in this study, although without the support of research regarding technical coefficients and productivity levels, are based on indications accepted as sound by P. juliflora researchers, none of them disagreeing with the figures arrived at here.
A well-managed P. juliflora plantation is competitive with other short-cycle crops traditional in the Brazilian semi-arid region.
References
azevedo, g., 1961: “Algaroba,” Rio de Janeiro, Ministério da Agricultura, Serviço de Informação Agrícola, 34 p.
emater/pe, 1978: “Sistema de Produção para a Cultura da Algaroba,” Recife, Mimeographed.
emparn/rn, 1982: “I Simpósio Brasileiro sobre Algaroba,” Natal, emparn, 407 p.
galvao, a.p.m., 1982: “A Experimentação Florestal da embrapa/ibdf/pnpe no Nordeste Brasileiro - A Pesquisa com Algaroba,” In: I Simpósio Brasileiro sobre Algaroba, emparn.
mendes, b.v., 1985: “Alternativas Technológicas para a Agropecuária do Semi-Arido,” São Paulo, Nobel, 171 p.
porto filho, f., 1981: “Estudo Comparativo de Custos e Receitas dos Principais Sistemas de Produção Recomendados pela emater/rn,” Mossoró, dsc/esam (Monograph).
ribeiro, m.j.t., 1980: “Incentivos Fiscais e Bem-Estar Social: Análise do Reflorestamento com Cajueiro no Nordeste,” Viçosa, ufv, 76 p. (M. Sc. Thesis)
