Salinization of irrigated agricultural land threatens ecological sustainability and livelihoods of people. Salinization is especially severe in the dry lowlands world-wide and in Central Asia where large amounts of salts accumulated in the soil profile, originating from shallow saline groundwater (GW).
An intensive process of land deterioration of some regions in Uzbekistan including the Aral Sea basin has led to a significant increase in soil salinity levels and consequently to a considerable reduction of total fertile soil area, as these lands are of little use for plant growth. The area is estimated to be more than 1.4 million ha of seabed. As a result, there was an immediate need to cultivate new crops capable of stopping the movement of sands and the enlargement of saline soils.
In 2005 the Uzbek government accelerated the dissolution process of collective farms through full-scale land reform. As the central production unit, the collective enterprise was supplanted by a private, family-based enterprise. Simultaneously Water Users Associations (WUAs) were established that operate and maintain the irrigation and drainage infrastructure of the former collective farms. Though these land-cum-water reforms could in principle initiate enormous changes, there is still a strong continuity due to the state-regulated agricultural system.
Land use and crop production in the Khorezm region in western Uzbekistan, exemplarily for the irrigated low-lands of Central Asia, is adversely affected by the excessive, non-sustainable use of irrigation water on one hand, repeated droughts on the other hand, and by soil degradation by secondary salinization.
Irrigated agriculture is widespread in the Central Asian drylands and important for food security of the region. However irrigation practices based on rules made for cotton production on large units do not provide adequate guidance for the now widespread small farms that produce cotton wheat and rice. Excessive unsustainable water use is the consequence. Land and water resource management practices were analysed in 2006 for the irrigated area (approx. 1885 ha) of a water users' association (WUA) as a case study.
The paper examines agricultural production and productivity growth in two Central Asian countries – Tajikistan and Uzbekistan. Both countries are characterized by a significant shift of resources from the traditional Soviet model of collective agriculture to more market-compliant individual and family farming. In both countries, the beginning of the policy-driven switch to family farming around 1997 coincided with the beginning of recovery in agriculture, namely resumption of agricultural growth after a phase of transition decline since 1991.
The Central Asian countries are particularly affected by the global climate change. The cultural and economic centers in this mostly arid region have to rely solely on the water resources provided by the rapidly melting glaciers in the Pamir, Tien-Shan and Alay mountains. By 2030, the available water resources will be 30 % lower than today while the water demand will increase by 30 %. The unsustainable land and water use leads to a water deficit and a deterioration of the water quality.
During the past two decades agrarian (‘land and farm’) reforms have been widespread in the transition economies of Eastern Europe, the Caucasus and Central Asia (EECCA), following earlier ones in Asia (China and Vietnam). However, independent family farms did not become the predominant sector in most of Eastern Europe. A new dual (or bi-modal) agrarian structure emerged, consisting of large farm enterprises (with much less social functions than they had before), and very small peasant farms or subsidiary plots.
Central Asia is one of the most vulnerable regions on the planet earth to global climate change, depending on very fragile natural resources. The Soviet legacy has left the five countries (Kazakhstan, Tajikistan, Kyrgyzstan, Turkmenistan, and Uzbekistan) with a highly integrated system but they are facing great challenges with tensions that hinder regional coordination of food and water resources.
Inefficient irrigation and the excessive use of water on agricultural land in the Aral Sea Basin over several decades have led to saline soils. The main objective of this paper is to identify the environmental predictors to model the spatial distribution of soil salinity in a highly irrigated landscape. Soil salinity at farm scale was measured in the topsoil (Total Dissolved Solids, TDS) and down to a depth of 1.5m by electromagnetic conductivity meter (CMv) over a regular grid covering an area of approximately 15km² in Khorezm Province, Uzbekistan.