The conversion of natural riparian forests into agricultural land affects ecological processes in Atlantic forest streams |
| |
| Institution: | 1. Instituto de Desenvolvimento Educacional de Passo Fundo - Faculdades IDEAU, Av. Rui Barbosa, 103, 99050120, Bairro Petrópolis, Passo Fundo, Rio Grande do Sul, Brazil;2. Programa de Pós Graduação em Ecologia, Universidade Regional Integrada do Alto Uruguai e das Missões, Av. Sete de Setembro, 1621, 99709-019, Erechim, Rio Grande do Sul, Brazil;3. Universidade Federal de Mato Grosso do Sul, Campus Três Lagoas, Av. Ranulpho Marques Leal, 3484, 79613-000, Três Lagoas, Mato Grosso do Sul, Brazil |
| |
| Abstract: | Agricultural practices affect the integrity of riparian areas of small streams. In this study we tested the hypothesis that the increase of agricultural activities influences negatively the functional conditions of the low order streams in the Atlantic forest of southern Brazil. Litter bags with leaves of Nectandra megapotamica (Spreng.) Mez were located in eight streams with different amounts of woody vegetation and agriculture land uses in their riparian zones. After 7, 15 and 30 days, the litter bags were removed for identification of associated invertebrates and determination of decomposition rate. Decomposition rates were negatively influenced by agriculture in the riparian zone while primary production was positively influenced. On the other hand, the decomposition mediated by microorganisms did not vary along the degradation gradient. The abundance of collectors increased in streams adjacent to agricultural land while the abundance of shredders was decreased. Our results showed that algae biomass and leaf decomposition were sensitive to the replacement of native vegetation by agricultural use. However, the trophic structure of invertebrates was moderately sensitive to agricultural land use. |
| |
| Keywords: | Agriculture Decomposition Ecological integrity Landscape ecology Primary production Riparian vegetation |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
