Water scarcity is one of the key problems that affect northern China, an area that covers 40 percent of the nation's cultivated area and houses almost half of the population. The water availability per capita in North China is only around 300 m3 per capita, which is less than one seventh of the national average. At the same time, expanding irrigated cultivated area, the rapidly growing industrial sector and an increasingly wealthy urban population demand rising volumes of water. As a result, groundwater resources are diminishing in large areas of northern China. For example, between 1958 and 1998, groundwater levels in the Hai River Basin fell by up to 50 meters in some shallow aquifers and by more than 95 meters in some deep aquifers.

Past water policies have not been effective in solving water scarcity problems. China's leaders have put priorities on increasing water supply through developing more canal networks or building more reservoirs. In 2001, the State Council started the South-to-North Water Transfer Project. However, these supply-side approaches cannot meet the increasing demand for water from all of the different sectors and cannot solve water scarcity problems in the long run.

The dramatic transition from Communism to market economies across Asia and Europe started in the Chinese countryside in the 1970s. Since then more than a billion of people, many of them very poor, have been affected by radical reforms in agriculture. However, there are enormous differences in the reform strategies that countries have chosen. This paper presents a set of arguments to explain why countries have chosen different reform policies.

In a book assessing the development of China during the People's Republic era, it is of interest to know how well agriculture has performed and the role that it has played in the development process. Has China produced food and other commodities that have contributed to China's growth? Has it been successful supplying labor to the off farm sector? How has agriculture contributed to the rise in rural incomes and growth, in general? In short, one of the overall goals of this chapter is to document the performance of the agricultural sector and use the criteria of Johnston and Mellor to assess how well the agricultural sector has done.

This chapter, however, seeks to go further than describing the achievements and shortfalls of China's agricultural economy; we also aim to identify the factors, both domestic policies and economic events as well as foreign initiatives, that have induced the performance that we observe. To create an agricultural economy that can feed the population, supply industry with labor and raw materials, earn foreign exchange and produce income for those the live and work in the sector and allow them to be a part of the nation's structural transformation requires a combination of massive investments and well-managed policy effort. The process can only proceed smoothly if an environment is created within which producers can generate output efficiently and earn a profit that can contribute to household income. Policies are required to facilitate the development of markets or other effective institutions of exchange. Although the sector is expected to contribute to the nation's development and allow for substantial extractions of labor and other resources, large volumes of investment also are needed. Investment in education, training, health and social services are needed to increase the productivity of the labor force when they arrive in the factories. Investment is needed in agriculture to improve productivity to keep food prices low, allow farmers to adopt new technologies and farming practice as markets change, and to raise incomes of those that are still in farming. Investment is needed in technology, land, water and other key inputs that are in short supply. In this chapter we seek to point out both policies that have facilitated the performance of the agricultural sector and those that have constrained it.

Most research on the agricultural impacts of climate change has focused on the major annual crops, yet perennial cropping systems are less adaptable and thus potentially more susceptible to damage. In regions where perennial crops are economically and culturally important, improved assessments of yield responses to future climate are needed to prioritize adaptation strategies. These impact assessments, in turn, must rely on climate and crop models that contain often poorly defined uncertainties. We evaluated the impact of climate change on six major perennial crops in California: wine grapes, almonds, table grapes, oranges, walnuts, and avocados. Outputs from multiple climate models were used to evaluate climate uncertainty, while multiple statistical crop models, derived by resampling historical databases, were used to address crop response uncertainties. We find that, despite these uncertainties, climate change in California is very likely to put downward pressure on yields of almonds, walnuts, avocados, and table grapes by 2050. Without CO2 fertilization or adaptation measures, projected losses range from 0 to >40% depending on the crop and the trajectory of climate change. Climate change uncertainty generally had a larger impact on projections than crop model uncertainty, although the latter was substantial for several crops. Opportunities for expansion into cooler regions were identified, but this adaptation would require substantial investments and may be limited by non-climatic constraints. Given the long time scales for growth and production of orchards and vineyards (30 years), climate change should be an important factor in selecting perennial varieties and deciding whether and where perennials should be planted.