Water quality of the Refugio Mata Redonda and surrounding rice paddies, Guanacaste, Costa Rica.
DOI:
https://doi.org/10.15517/am.v24i2.12538Keywords:
water quality, rice, pesticides, agro-chemicals in wetlands.Abstract
The objective of this study was assess if the water quality from the Mata Redonda lagoon (MRL) and from the rice fields in San Lazaro sector of Nicoya, is appropriate for biodiversity and aquatic life development. The water quality analysis was carried out using the Water quality index for managing flood lagoons (ICA-L), which is based on the following data: temperature, pH, oxygen saturation percentage, electrical conductivity, biochemical oxygen demand, suspended solids, nitrate content and total phosphorus content. The ICA-L average (ICA-Lp) from the water drained form the rice fields in the main channel was 42, which corresponds to a ¨bad¨ category value (unfit for sustaining biodiversity in flood lagoons). In the MRL (ICA-Lp 80) and in the lagoon´s drainage (ICA-Lp 81), water quality was classified as “good”. Nevertheless, increases in total phosphorus and the biological oxygen demand (BOD) may cause negative changes in the composition of the ecosystem. The risk level associated with pesticide application in rice fields (under the San Lazaro area conditions during the study period) was estimated using the Pesticide Impact Rating Index (PIRI). The PIRI results showed that the less appropriate to use pesticides are: deltamethrin, esfenvalerate, permethrin and butachlor, because of their high toxicity and mobility. On the other hand, imidapropid, bispyribac-Na, triazophos, glyphosate, acephate, clomazone and tricopyr, would be less dangerous if applied under appropriate practices.
Downloads
Downloads
How to Cite
Issue
Section
License
1. Proposed policy for open access journals
Authors who publish in this journal accept the following conditions:
a. Authors retain the copyright and assign to the journal the right to the first publication, with the work registered under the attribution, non-commercial and no-derivative license from Creative Commons, which allows third parties to use what has been published as long as they mention the authorship of the work and upon first publication in this journal, the work may not be used for commercial purposes and the publications may not be used to remix, transform or create another work.
b. Authors may enter into additional independent contractual arrangements for the non-exclusive distribution of the version of the article published in this journal (e.g., including it in an institutional repository or publishing it in a book) provided that they clearly indicate that the work was first published in this journal.
c. Authors are permitted and encouraged to publish their work on the Internet (e.g. on institutional or personal pages) before and during the review and publication process, as it may lead to productive exchanges and faster and wider dissemination of published work (see The Effect of Open Access).
