Cambodia has been identified as one of the most vulnerable countries to climate change, given the predicted changes in temperature and precipitation, the share of labor in agriculture, and the country’s low adaptive capacity due to widespread poverty. In this study, we use climate data from four general circulation models (GCMs) to evaluate the impact of climate change on agriculture in Cambodia by 2050. We used the Decision Support System for Agrotechnology Transfer crop modeling software to evaluate crop yields, first for the 1950–2000 period (actual climate) and then for the climates given by the four GCMs for 2050. We evaluated crop yields for eight different crops at 2,162 points in Cambodia, using a grid of 10-kilometer squares, for 2000 and 2050. For each crop, we searched for the best cultivar (variety) in each square, rather than assuming the same cultivar to be used in all locations. We also searched for the best planting month in each square. We explored potential gains from changing fertilizer levels and from using irrigation to compensate for rainfall changes. This analysis indicates that when practiced together, using improved cultivars better suited for the changing climate conditions and adjusting planting dates can lessen the impact of climate change on yields, including for both wet- and dry-season rice. In addition, the analysis shows that losses in yield due to climate change can be compensated for—for many crops—by increasing the availability of nitrogen in the soil. To provide context to the modeling analysis, a survey of 45 communes was conducted using focus group discussions to solicit information on agricultural practices. Questions were asked about fertilizer, irrigation, seeds, tillage, and pest management, as well as about natural disasters and how farmers respond. Key results indicate that in response to extreme weather, only 7 to 16 percent of farmers report changing crop variety and only 20 percent of farmers report changing planting dates. Since the modeling results indicate that adaptation to climate change by changing crop variety and planting dates will be critical in order to avoid yield losses over the next 40 years, it is recommended that farmers expand their capacity to adapt in this way. In addition, every commune reported using some type of chemical fertilizer; however, in a typical commune, only 50 percent of the farmers were using any chemical fertilizer. This indicates that there is room to increase the use of chemical fertilizers. Finally, focus group participants were asked to name the top three natural disasters of concern. Drought was the most cited, reported in 44 of the 45 communes (98 percent), while flooding was cited in 67 percent of the communes surveyed. Despite this, in fully 58 percent of the communes, farmers reported taking no action in response to floods. In response to drought, farmers reported switching to other crops in 16 percent of the communes, and changed planting dates in 19 percent, while only 7 percent of the communes reported no adaptation in farming practices. These findings indicate the need for intervention to help farmers deal with floods in particular, and to determine whether strategies for adapting to drought are the best suited to mitigate crop loss.

This publication presents an assessment of Cambodia’s agriculture, natural resources, and rural development (ANRRD) sector and provides a strategy and road map for its future development. It identifies the strategic investment priorities of the Government of Cambodia where the Asian Development Bank (ADB) can contribute to ANRRD productivity, value addition, and resource efficiency. ADB support will focus on three key areas: (i) enhancing agricultural productivity through a whole-of-system water resources management approach, (ii) strengthening agricultural value chains, and (iii) improving natural resources management and disaster resilience.

Rice in the Cambodian economy: past and present; Topography, climate, and rice production; Soils and rice; Rice-based farming systems; Rice ecosystems and varieties; Pest management in rice; Farm mechanization; Capture and culture ricefield fisheries in Cambodia; Constraints to rice production and strategies for improvement.

This open access book is about understanding the processes involved in the transformation of smallholder rice farming in the Lower Mekong Basin from a low-yielding subsistence activity to one producing the surpluses needed for national self-sufficiency and a high-value export industry. For centuries, farmers in the Basin have regarded rice as “white gold”, reflecting its centrality to their food security and well-being. In the past four decades, rice has also become a commercial crop of great importance to Mekong farmers, augmenting but not replacing its role in securing their subsistence. This book is based on collaborative research to (a) compare the current situation and trajectories of rice farmers within and between different regions of the Lower Mekong, (b) explore the value chains linking rice farmers with new technologies and input and output markets within and across national borders, and (c) understand the changing role of government policies in facilitating the on-going evolution of commercial rice farming. An introductory section places the research in geographical and historical context. Four major sections deal in turn with studies of rice farming, value chains, and policies in Northeast Thailand, Central Laos, Southeastern Cambodia, and the Mekong Delta. The final section examines the implications for rice policy in the region as a whole.

This report is a contribution to an assessment of the current status of agriculture in Cambodia, focusing on the linkages between agriculture and water, mainly in the form of irrigation. It seeks to view current government policies on agriculture and irrigation in the context of experiences on the ground, as communicated through the many field studies that cover varied aspects of performance in the agriculture sector and irrigation schemes. In an effort to identify future research areas, this review examines the status quo, and connects or disconnects with stated policy through a broad lens to capture strengths and challenges across crop production, irrigation management and post-harvest contexts. It places irrigation under scrutiny in terms of its value as a major area of government expenditure in recent years, and asks whether it presents the best potential for future gains in productivity, when compared with the prospects offered by investments in other aspects of agriculture. The fieldwork and review of current literature that form the basis of this report were undertaken at the request of, and partly funded by, the Australian Centre for International Agricultural Research (ACIAR). It is also intended to contribute knowledge to the CGIAR Research Program on Aquatic Agricultural Systems (AAS) led by WorldFish, who co-funded the activities.

This field guide covers the major resource groups likely to be encountered in the fisheries of the Cambodian Mekong. These groups include sharks, batoid fishes and bony fishes. The introduction outlines the geographical, environmental and ecological factors influencing fisheries, and the basic components of the fisheries of the Cambodian Mekong. As an aid to identification to higher taxonomic levels, a pictorial index to families and an illustrated guide to orders and families are included. Each species account provides scientific nomenclature, FAO names in English, local names, sizes, notes on fisheries, habitat and biology, and one or more illustrations. The guide is fully indexed and a list of related literature is appended. Finally, 27 colour plates are presented.

Cambodia has a potential advantage in agricultural production due to significant amounts of fertile land and high levels of agricultural employment, but rice production and commercialization remain well below potential. This study uses a farm investment climate assessment to provide evidence on key areas where government investments and policy reforms can lead to higher levels of rice production and commercialization in small farms. Improving output markets through domestic milling and increasing the area irrigated are found to be related to increased production efficiency, commercialization, rice sold, and value of sales.