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Yellow River Comprehensive Assessment, Basin Features and Issues
(2003) Zhu, Zhongping; Giordano, Mark; Cai, Ximing; Molden, David; Shangchi, Hong
"A new report assessing the state of China's Yellow River could offer hope in providing much needed answers to the critical water management problems facing the countries 2nd longest river. The assessment carried out by researchers from the International Water Management Institute (IWMI) and the Yellow River Conservancy Commission (YRCC). The report was carried out as part of the Comprehensive Assessment of Water Management in Agriculture, an international research program. The findings are stark. They highlight the four major challenges currently facing the river as being increased water scarcity, degraded environment, massive soil conservation needs and constant flood threats."
Does International Cereal Trade Save Water? The Impact of Virtual Water Trade on Global Water Use
(2004) de Fraiture, Charlotte; Cai, Ximing; Amarasinghe, Upali A.; Rosegrant, Mark; Molden, David
"Virtual water refers to the volume of water used to produce agricultural commodities. When these commodities enter the world market, trade in virtual water takes place. This report argues that the role of virtual water trade in global water use is modest, since most trade takes place, and will continue to take place, between water abundant countries."
Integrated Land and Water Management for Food and Environmental Security
(2003) Penning de Vries, F.W.T.; Acquay, H.; Molden, David; Scherr, Sara J.; Valentin, C.; Cofie, Olufunke O.
"This document focuses on the impact of degradation of land and water on food and environmental security. It aims to provide a basis for priority policy and research actions that will counteract the progression of degradation and will reduce its impact on household food security and the loss of other ecosystem services."
Accounting for Water Use and Productivity
(1997) Molden, David
"All science depends on its concepts. These are ideas which receive names. They determine the questions one asks, and the answers one gets. They are more fundamental than the theories which are stated in terms of them."
Basin-Level Use and Productivity of Water: Examples from South Asia
(2001) Molden, David; Sakthivadivel, R.; Habib, Zaigham
"Increasing water scarcity poses a threat to food security and safe domestic water supplies. Irrigated agriculture is a major driver in leading to water scarcity because of its high consumption of water resources. Obtaining more benefits from each drop of water consumed, especially from each drop irrigated agriculture consumes, will be key to mitigating problems of scarcity. The means of improving productivity of water are not always immediately apparent due to the complex nature of water diversions and return flows within basins. The purpose of this report is to discuss and illustrate concepts for identifying ways of improving productivity of water within basins. We applied a water accounting procedure to four subbasins in South Asia where there are perceived problems of water scarcity: Bhakra in India, Chishtian in Pakistan, Huruluwewa in northern Sri Lanka and Kirindi Oya in southern Sri Lanka. The accounting procedure identifies the quantities and productivity of various uses of water within a basin. This information is used to identify the water-saving potential, and the means of improving the productivity of the managed supplies. At Bhakra and Chishtian, there is little remaining prospect for water savings, while at Huruluwewa and Kirindi Oya, there is considerable opportunity for water savings and increasing beneficial use. At Chishtian, almost all water is consumed by beneficial uses, but considerable scope remains for improving the productivity of water. In all four of the cases we analyzed, productivity of water that is presently being depleted by agriculture can be improved. The four subbasins are representative of situations that we believe are typical of many other basins worldwide. With the methodology used, we were able to shed light on opportunities to increase water productivity. It appears that the methodology is thorough and robust, and can be applied to other basins."
Land and Water Productivity of Wheat in the Western Indo-Gangetic Plains of India and Pakistan: A Comparative Analysis
(2003) Hussain, Intizar; Sakthivadivel, R.; Amarasinghe, Upali A.; Mudasser, Muhammad; Molden, David
"The purpose of this study is to analyze variations in wheat yields and to assess the range of factors affecting wheat yields and profitability of wheat production in the selected irrigation systems in India and Pakistan. The study attempts to identify constraints and opportunities for closing the existing yield gaps. It is hypothesized that substantial gains in aggregate yields can be obtained by improved water management practices at the farm and irrigation-system levels."
Implications of Land and Water Degradation for Food Security, with Particular Reference to Asia and Africa
(2002) Penning de Vries, F.W.T.; Molden, David
From Introduction: "It is common fallacy that land is ample and indestructible, and that clean water rains on us every day. Loss and degradation of these natural resources is widespread, particularly in developing countries. The reality is that this degradation threats our future and that of our children. Another common mental image that is that of gradual change: that degradation proceeds slowly and can be reversed, slowly, with adequate inputs. Yet, agroecological systems and societies are reilient only up to a threshold, and collapse when pushed too far. The rates of natural resources degradation may seem slow to some, but this should not lull us into complacency."
Rice Impact in Henan Irrigation Districts along the Lower Yellow River Reaches
(2003) Bin, Dong; Zhichen, Liang; Loeve, Ronald; Molden, David; Baozhong, Yang
"The Henan Province, located in the lower reaches of the Yellow River Basin, is one of the staple areas of food production in China. There are 26 large and medium-sized irrigation districts along the river and the total area irrigated by Yellow River water is 523.56 thousand hectares, of which 85 thousand hectares are paddy fields, accounting for 16% of the total irrigated area in Henan. Traditionally, the deep flooding irrigation method is used and the field irrigation duty during rice growing season is about 1500 - 1800mm, so a large quantity of water diverted from the river is used for rice production. However, the shortage of water resources in the Yellow River Basin has become very serious, therefore the rice culture in the irrigation districts and its impact on Yellow River water diversion are worthwhile to pay attention and discuss. This paper firstly has an introduction of the Henan irrigation districts along the Yellow River reaches and the current status of rice culture in the irrigation districts. Then, the major impacts of rice cultivation are summarized according to the data collected from some main irrigation districts. Finally, the trend of rice cultivation at the irrigation districts is discussed, and some appropriate management options are suggested."
World Water Demand and Supply, 1990 to 2025: Scenarios and Issues
(1998) Seckler, David; Amarasinghe, Upali A.; Molden, David; de Silva, Radhika; Barker, Randolph
"Presents two alternative scenarios of water demand and supply for 118 countries over the 1990 to 2025 period and develops indicators of water scarcity for each country and for the world as a whole. This study is the first step in IWMI's long-term research goal: to determine the extent and depth of water scarcity, its consequences for individual countries and what can be done about it."
Hydronomic Zones for Developing Basin Water Conservation Strategies
(2001) Molden, David; Sakthivadivel, R.; Keller, Jack
"In this report, the concept and procedures of hydronomic (hydro water + nomus management) zones are introduced. A set of six hydronomic zones are developed and defined based on key differences between reaches or areas of river basins. These are the: Water Source Zone, Natural Recapture Zone, Regulated Recapture Zone, Stagnation Zone, Final Use Zone, and Environmentally Sensitive Zone. The zones are defined based on similar hydrological, geological and topographical conditions and the fate of water outflow from the zone. In addition, two conditions are defined which influence how water is managed: whether or not there is appreciable salinity or pollution loading; and whether or not groundwater that can be used for utilization or storage is present. Generic strategies for irrigation for four water management areas, the Natural Recapture, Regulated Recapture, Final Use, and Stagnation Zones, are presented. The Water Source Zone and Environmentally Sensitive Zone are discussed in terms of their overall significance in basin water use and management. "Hydronomic zones allow us to define, characterize, and develop management strategies for areas with similar characteristics. The concept of zoning is demonstrated in four agricultural areas representing a wide variety of situations: the Kirindi Oya basin in Sri Lanka, Egypts Nile basin, the Bhakra command area in Haryana, India and the Gediz basin in Turkey. We were readily able to apply the zones within each basin and suggest water management strategies for each zone. Hydronomic zones hold potential as a tool to help us better understand complex water interactions within river basins, to isolate similar areas within basins and to help us develop sets of water management strategies better tailored to different conditions within basins."

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