A fertilidade do solo em unidades de conservação no município de Belém (PA).

Abstract

1) The Belém Ecologic Park is an urban conservation unit created in 1991 due the necessity to preserve and keeps adequate environment conditions in relation the city expansion, in which it promoted total destruction of the vegetation. The environment of Igapó be presents in 73% of the park, as well as there be high floodplain forest and firm earth. The area is a local of antropic influences with detection of garbage deposition. The drenage ofthe São Joaquim river, with avenue construction in area equivalent at 18% of the park. This activity can have influenced the results in the firm earth, in which it were found high tenors of phosphor available in the layers studded and lowers tenors of potassium and sodium, as well as low effective CTC. The park to receive influences of the urban environment through of discharge of the Burrinho river, São Joaquim river, in which it are rivers polluted by receive drain not treated. The environment was divided in firm earth, low floodplain and igapó with objective of carried out the study. Ali the extracts present eutrófics with low saturation of the aluminum ion. In this area is recommended the carrying out of the organic matter determination and CTC potential of this environment, as well as the study of the soil fertility.

2) The Rodrigues Alves Park is the more old conservation unit n the Belém city, Pará state, in which it had the soil fertility determined with aim to explain the preservation activities of this unit. The soil samples were harvested and analyzed, as well as it was carried out 96 simple samples, besides the horizon samples carried out during the description of the soil proíiles. The soil was classified as Distrofic Yellow Latossoil in the park with area of 15 ha. The organic matter presented médium values in the superficial layers and predominam the presence of sand in the soil. Whereas it presents low tenors of exchange bases and saturation of bases, in which it indicate eutrófic environment with consequent low saturation of aluminum. The pH is low indicating high acidity. As the aluminum ion be presents only in the soil inferior layers is interesting in future investigations to evaluate the potential acidity with the objective to monitor the soil fertility. The morphological description in the profile indicates the presence of structures well developed and great amount of macro and micro pores, in which it promotes adequate drenage and retention of soil solution. The regular evaluation of the soil fertility is recommended due the fragility of the ecosystem.

3) The Emílio Goeldi Museum is a research institution in Belém city, Pará state, in which it presents a significant urban conservation unit in local strongly habited. The soil nutritional study through ofthe soil fertility was carried out with the aim ofpreservation ofthis environment. In the area of 5 ha coming from campus, between historie and new constructions there be century vegetation that take proximity 2.5 of efficient plant layer. The simple samples were submitted the granulométric and chemical analyze, as well as it were carried out 40 samples. The soil is decrypted as Yellow Latossoil sand, with médium acidity, as well as it oscillating among 5.5 and 6.5, and high values of organic matter incorporated to soil. In relation to exchange bases were showed low tenors ofcalcium, magnesium, potassium and sodium in ali the environments. As the change aluminum content is low, the effective CTC presented low value in the area, as well as the potential acidity. With the low participation ofthe potential acidity in this system the saturação de bases saturationpresented values of proximity 50%, besides eutrófic in two sites. In the samples evaluated was found great sand amount. In this area is recommended the regular study of the soil fertility due the great possibility of change of this environment promoted by the antrópic action.