Performance of larval amphibians and aquatic insects in agroindustrial landscapes

• Grant number: 13/19834-9
• Support Opportunities: Scholarships in Brazil - Master
• Start date: December 01, 2013
• End date: October 31, 2014
• Field of knowledge: Biological Sciences - Ecology - Applied Ecology
• Principal Investigator: Luis Cesar Schiesari
• Grantee: Daniel Din Betin Negri
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 08/57939-9 - Impacts of the expansion of the sugarcane agroindustry on freshwater communities, AP.BIOEN.JP

Abstract

The increase in human population size and in per capita consumption patterns have created a strong demand for food, fiber and biofuels that depends on an industrial model of agricultural production. However, agriculture is one of the most impacting human activities, prompting researchers worldwide to debate how to reconcile agricultural production with biodiversity conservation. Two opposing strategies have been formulated: 'land sharing' proposes to integrate agricultural production and biodiversity conservation in the same land by adopting ´wildlife friendly´ land management practices, at a cost of low productivity and therefore need for larger territorial expanses. In turn, ´land sparing´ proposes to spatially segregate agricultural production and biodiversity conservation. In this strategy, intensive agriculture would permit achieving high yields and therefore sparing lands that could be used for biodiversity conservation elsewhere. It is important to note, however, that this model tends to create landscapes in which habitat patches are embedded in matrices of low permeability, threatening the local and even regional persistence of the many species that demographically function as metapopulations. For this reason, it is important to objectively test the degree to which agricultural landscapes are permeable to the movement of wildlife, and what factors contribute to matrix permeability. Within the framework of a Young Researcher Award to my advisor, this project proposes to test the hypothesis that changes in the physical, chemical and biological properties of the environment that result from land use change in agroindustrial landscapes have significant detrimental effects to the performance of freshwater organisms. This hypothesis will be tested by a combination of field and laboratory experiments using as model system temporary ponds and their communities, and having as environmental context the conversion of savannas to pastures and soybean field in the headwaters of the Xingu River in the Southern Amazon. Field experiments consist in transplanting aquatic insects and tadpole populations to enclosures in ponds distributed across a gradient of environmental degradation (savannas < pastures < soybean fields). Simultaneously, aquatic insects and tadpoles of the same species and lots will be brought to a laboratory experiment separating the relative contributions of water and sediments originating from the same ponds selected for the transplant experiments to organismal performance. All experiments will use as response variable growth rates, developmental rates and survivorship. Hence, the laboratory experiments will allow for a more solid interpretation of the factors that may be regulating the performance of aquatic organisms in the field.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

NEGRI, Daniel Din Betin. Performance of amphibian and dragonfly larvae in an agro-industrial landscape. 2015. Master's Dissertation - Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) São Paulo.