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    R. Quiroz

    High-altitude ecosystems shelter important reserves of biodiversity, water provision and soil organic carbon (SOC) stocks. Climate change, agricultural encroachment, overgrazing, and mining activities are endangering ecosystems... more
    High-altitude ecosystems shelter important reserves of biodiversity, water provision and soil organic carbon (SOC) stocks. Climate change, agricultural encroachment, overgrazing, and mining activities are endangering ecosystems sustainability, particularly in the high-Andean Puna. Increasing food demands in a region with limited agricultural land calls for agricultural intensification. Ecological intensification of agriculture is a framework for increasing agricultural productivity by fostering supporting and regulating ecosystem services (ES) while reducing negative environmental impacts. In this review we examine how agriculture use and disturb the provision of key ES in this ecoregion – food, wool and fiber provision, soil fertility, nutrient cycling, soil carbon sequestration, water provision and regulation, genetic resources, pest and disease control, pollination regulation and microclimate regulation. We also propose a set of technologies, practices and policies to preserve (or restore) the provision of these key ES: long fallowing, soil amendments, conservation tillage, rotational grazing, grassland ecological restoration, conservation of agrobiodiversity, modern irrigation and water harvesting, plant breeding, climate change mitigation schemes and payment for ecosystem services, and adapted traditional technologies.
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    Wetlands are valuable for their function as C sinks, water conservation and filtering, flood control, and as a recreational landscape. In the Central and Southern Andes, peatlands (aka, bofedales) are also a source of good quality... more
    Wetlands are valuable for their function as C sinks, water conservation and filtering, flood control, and as a recreational landscape. In the Central and Southern Andes, peatlands (aka, bofedales) are also a source of good quality pastures for wild and domestic South ...
    Research Interests:
    Knowledge of drought tolerance in potato is limited and very little is known about stress memory in this crop. In the present study, long-term stress memory was tested on tuber yield and drought tolerance related traits in three potato... more
    Knowledge of drought tolerance in potato is limited and very little is known about stress memory in this crop. In the present study, long-term stress memory was tested on tuber yield and drought tolerance related traits in three potato varieties (Unica, Désirée and Sarnav) with contrasted yields under water restriction. Seed tubers produced by plants grown under non-restricted (non-primed tubers) and restricted (primed tubers) water conditions were sown and exposed to similar watering treatments. Tuber yield and leaf greenness of plants from primed and non-primed seeds as well as tuber carbon isotope discrimination (!13C) and antioxidant activity (AA) responses to watering treatments were compared.

    Higher tuber yield, both under non-restricted and restricted water regimes, was produced by primed Sarnav plants. The decrease of tuber yield and !13C with water restriction was lower in primed Unica plants. Long-term stress memory consequently appears to be highly genotype-dependent in potato. Its expression in plants originated from primed tubers and facing water restriction seems to be positively associated to the degree of inherent capability of the cultivar to yield under water restriction. However, other effects of priming appear to be genotype-independent as priming enhanced the tuber AA in response to water restriction in the three varieties.
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    Downscaling techniques aim at resolving the scale discrepancy between climate change scenarios and the resolution demanded for impact assessments. Requirements for downscaled climate, to be useful for end users, include reliable... more
    Downscaling techniques aim at resolving the scale discrepancy between climate change scenarios and the resolution demanded for impact assessments. Requirements for downscaled climate, to be useful for end users, include reliable representation of precipitation intensities, temporal and spatial variability, and physical parameters consistency. This report summarizes the results of the proof of concept phase in the development and testing of a novel data reconstruction method and a downscaling algorithm based on the multiplicative random cascade disaggregation method using rainfall signals at different spatial and temporal resolutions. The Wavelet Transformed-based Multi-Resolution Analysis (WT-MRA) was used for reconstructing the historical daily rainfall data needed as input for the downscaling methodology, using satellite-derived proxy data. Comparisons with presently used software showed that in all the cases; that is, the reconstructed, generated daily or downscaled daily data, the products developed outperformed the control test by either generating more accurate outcomes or by demanding significantly less parameterizing data.
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    Potato Yellow Vein Virus (PYVV) threatens potato production in South America. Visual field monitoring is commonly used to detect PYVV on potato crops but the disease is generally detected only after significant damage has occurred to... more
    Potato Yellow Vein Virus (PYVV) threatens potato production in South America. Visual field monitoring is commonly used to detect PYVV on potato crops but the disease is generally detected only after significant damage has occurred to photosynthetic tissues. Therefore, a method for detecting the disease before yields are severely affected would be useful. Remotely sensed multispectral reflectance, based on the