Charlotte de Fraiture

Sustainable intensification of agriculture for human prosperity and global sustainability.

There is an ongoing debate on what constitutes sustainable intensification of agriculture (SIA). In this paper, we propose that a paradigm for sustainable intensification can be defined and translated into an operational framework for agricultural development. We argue that this paradigm must now be defined—at all scales—in the context of rapidly rising global environmental changes in the Anthropocene, while focusing on eradicating poverty and hunger and contributing to human wellbeing. The criteria and approach we propose, for a paradigm shift towards sustainable intensification of agriculture, integrates the dual and interdependent goals of using sustainable practices to meet rising human needs while contributing to resilience and sustainability of landscapes, the biosphere, and the Earth system. Both of these, in turn, are required to sustain the future viability of agriculture. This paradigm shift aims at repositioning world agriculture from its current role as the world’s single largest driver of global environmental change, to becoming a key contributor of a global transition to a sustainable world within a safe operating space on Earth.

Indicators of Land and Water Productivity in Irrigated Agriculture

A set of four comparative performance indicators is defined, which relates outputs from irrigated agriculture to the major inputs of water and land. These indicators are presented with the objective of providing a means of comparing performance across and within irrigation systems. They require a limited amount of data that are generally available and readily analysed. Four typical applications of these indicators are illustrated: cross-system comparison; temporal variations in performance at one system; spatial variations within one system; and comparing performance by system type. Results of application of the indicators at 40 irrigation systems show large differences in performance among and within systems. In spite of uncertainties in estimation of indicators, the large differences discerned by the indicators justify the approach taken.

Can rainfed agriculture feed the world?: an assessment of potentials and risk

Agriculture is practised on 12% of the total land area, hosting around 42% of the global population (FAOSTAT, 2000, 2003). Most of this area, around 80%, is under rainfed agriculture (FAOSTAT, 2005), which plays a predominant role in global food supply and water demand for food. There are large regional variations. While the majority of the agricultural land in sub-Saharan Africa is rainfed, most of the agricultural production in South Asia comes from irrigated agriculture. Approximately 7000 km3 of water is used annually in crop production (Rockström et al., 1999; de Fraiture et al., 2007; Lundqvist et al., 2007), corresponding to 3000 l/person/day. The majority of this water originates from the green water resource (78%), while the remaining 22% is met by irrigation (de Fraiture et al., 2007). Today, more than 1.2 billion people live in water-scarce river basins (Molden et al., 2007a), and recent forecasts warn of aggravated global water scarcity unless water resources management is changed (Alcamo et al., 1997; Seckler et al., 1998; Seckler and Amarasinghe, 2000; Shiklomanov, 2000; Rosegrant et al., 2002a, 2006; Bruinsma, 2003; Falkenmark and Rockström, 2004; SEI, 2005). With rising incomes and growing population, food demand is expected to increase by 70–90% (de Fraiture et al., 2007). Food habits change with increasing GDP (gross domestic product) to include more nutritious and more diversified diets, resulting in a shift in consumption patterns among cereal crops and away from cereals towards livestock products and high-value crops such as fruits, vegetables, sugar and edible oils; however, regional and cultural differences are large. Bioenergy is expected to add to the demand of agricultural produce, in order to increase the supply of transport fuels (i.e. biofuels) as a response to rising energy prices, geopolitics and concerns over greenhouse gas emissions. Future water requirements for bioenergy production have been estimated to range from 4000 to 12,000 km3/year (Lundqvist et al., 2007). The large uncertainty is a reflection of difficulties in estimating water productivity, which, for example, depends on how much of the biomass can be used for bioenergy production. One of the options to respond to increased pressure on water resources is to boost low productivity through investments in water management in rainfed agriculture. There are several compelling environmental, social and economic reasons to do so. Yet, with rapidly growing and changing agricultural demand and increased climate variability due to climate change, the potential of rainfed agriculture to meet future food demand is subject to debate.

Small pumps and poor farmers in Sub-Saharan Africa: an assessment of current extent of use and poverty outreach

The expansion of irrigation in Sub-Saharan Africa has been slow. In Asia, the rapid expansion of smallholder irrigation systems was attributed in part to the availability and affordability of motorized pumps. This paper appraises the current extent of pump-based irrigation in Sub-Saharan Africa; profiles the socio-economic and demographic attributes of current pump adopters; and assesses the poverty outreach of small-pump technology. It shows that private smallholder irrigation is practised mainly by the wealthier farmers. The development of groundwater irrigation requires targeted and deliberate public-policy interventions and institutional support focusing on the more marginal farmers.

Water availability and its use in agriculture

Water scarcity is a reality in the world today, and is a major threat to our food production systems that have to provide enough food for a growing and wealthier population. Managing water for agriculture is a major part of the solution for scarcity. This chapter provides information on water availability and its use in agriculture now and in the future. Detail is provided on rainfed, irrigated, fish and livestock systems, the governance of water in river basins, and environmental and health implications.

Retrieval of irrigated and rainfed crop data using a general maximum entropy approach

This paper presents a method to separate harvested area and yield for irrigated crops from rainfed crops in a region, given gross harvested area and yield, and climatic, agronomic and economic data for crops. The method is based on the principle of general maximum entropy, which combines incomplete data, empirical knowledge and a priori information to derive desired information. The model is applied to three large basins with aggregated climatic and agricultural conditions, and to five counties in Texas and California. The modeled results and assessed values in these study areas are compared. While the dependability of model outputs relies on empirical knowledge and judicious parameter estimation, the model remains reliable even for the significant level of uncertainty produced by subjectively predetermined major parameters. The model can be applied to retriving historical data for irrigated and rainfed crops; it can also be used for irrigated and rainfed agriculture planning based on climatic and technological projections. Moreover, the model provides other useful information, including water allocation by crop, water use efficiency and the impact of other agricultural inputs.