Title
On-farm diversity offsets environmental pressures in tropical agro-ecosystems: A synthetic review for cassava-based systems
Date Issued
01 January 2018
Access level
metadata only access
Resource Type
review
Author(s)
Delaquis E.
Wyckhuys K.
International Center for Tropical Agriculture
Publisher(s)
Elsevier B.V.
Abstract
Ecosystem integrity is at risk across the tropics. In the quest to meet global dietary and market demands, tropical agro-ecosystems face unrelenting agricultural intensification and expansion. Agro-biodiversity can improve ecosystem stability and functioning, but its promotion in smallholder-based systems faces numerous practical hurdles. In the tropics, cassava (Manihot esculenta Crantz) is cultivated on over 25 million hectares and features as the third most important source of calories. Cassava crops are often maintained by resource-poor farmers who operate on marginal lands, at the fringes of sensitive, biodiverse habitats. As traditional intercropping schemes are gradually abandoned, monoculture cassava systems face stagnating yields, resource-use inefficiencies and agro-ecosystem degradation. A global literature search identified 189 cassava intercropping studies, covering 330 separate instances of intercropping systems. We employed a vote-counting approach and simple comparative measure across a subset of 95 studies to document the extent to which intercropping sustains a bundle of ecosystem services. Across geographies and biophysical conditions, a broad range of intercrops provided largely positive effects on five key ecosystem services: pest suppression, disease control, land equivalency ratio (LER), and soil and water-related services. Ecosystem services were augmented through the addition of a diverse range of companion crops. Results indicated 25 positive impacts vs. 3 negative impacts with the addition of maize, 5 vs. 1 with gramineous crops, 23 vs. 3 with four species of grain legumes, and 9 vs. 0 with trees. Appropriate intercropping systems can help to strike a balance between farm-level productivity, crop resilience, and environmental health. Our work highlights an urgent need for interdisciplinary research and systems-level approaches to identify intensification scenarios in which crop productivity, provision of ecosystem services, biodiversity conservation, and human well-being are all balanced.
Start page
226
End page
235
Volume
251
Language
English
OCDE Knowledge area
Ciencias agrícolas
Scopus EID
2-s2.0-85042183703
Source
Agriculture, Ecosystems and Environment
Resource of which it is part
Agriculture, Ecosystems and Environment
ISSN of the container
01678809
Source funding
European Commission
Sponsor(s)
This initiative was conducted as part of an EC-funded, IFAD-managed, CIAT-executed program (CIAT-EGC-60-1000004285). Research was undertaken as part of, and funded by, the CGIAR Research Program on Roots, Tubers and Bananas (RTB) and supported by CGIAR Fund Donors: http://www.cgiar.org/about-us/our-funders/. This initiative was conducted as part of an EC -funded, IFAD-managed, CIAT-executed program ( CIAT-EGC-60-1000004285 ). Research was undertaken as part of, and funded by, the CGIAR Research Program on Roots, Tubers and Bananas (RTB) and supported by CGIAR Fund Donors: http://www.cgiar.org/about-us/our-funders/.
Sources of information: Directorio de Producción Científica Scopus