Yield gaps and ecological footprints of potato production systems in Chile

摘要

In Chile, potatoes are grown in a wide range of ecological zones and levelsof technology resulting in wide ranges of crop management and yields. The aim of thepresent study was to assess yield gaps, resource use efficiencies and foot-printing indifferent potato cropping zones between 18 and 53° South considering early and latecrops, small and large holdings (>10 ha/year) and ware and seed potato crops. Twomathematical tools were used to generate data for comparisons: the light interceptionand utilization simulator for potato crops (LINTUL-Potato) to calculate potential yieldsand water need of each system and the Cool Farm Tool – Potato (CFT) to calculate theamount of CO2 associated with the production of 1 ton of potato. Meteorological datafor LINTUL-Potato came from official services, and data needed to complete the CFTcame from a survey carried out for the 10 sites yielding amounts of inputs and numberof operations, potato yields and planting and harvesting dates. The survey yielded 20cropping systems with an average yield of 31 t ha−1. Yields were related to daily growthrate and not to the length of the growing season. Considerable variation was found inresource-use efficiency and CO2 emission. It was concluded that large farms show alower land footprint than small farms due to a higher technological level, but whileapplying more water and fertilizer, they result in higher water and CO2 footprints. Latecrops may fetch higher off-season prices but have higher land, water and CO2 footprints.The most suitable potato production systems are the rain-fed summer crops inthe South with the lowest footprints. The highest footprints have the irrigated wintercrops in the centre of Chile. The subsistence high altitude Andean crop in the utmostNorth has the highest land footprint but the lowest CO2 emission. The description,analysis and benchmarking of the potato production systems in Chile allow strategiesfor improving footprints and profitability and yields information about future investmentsin research, development and production of the crop.