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versión On-line ISSN 0718-3429
Idesia vol.30 no.2 Arica ago. 2012
Volumen 30, Nº 2 Páginas 3-10 IDESIA (Chile)
Productive agricultural systems in the desert macro-region of Chile
Dean, Faculty of Agronomic Sciences,Universidad de Tarapacá, Arica-Chile. E-mail: firstname.lastname@example.org
The development of agriculture in emerging countries is an important means of reducing poverty and activating their economies, considering that the commercialization of agricultural products is a source of generation of wealth, especially those associated with international markets. However, small and medium agriculture also play an important role in local economies; even though they do not generate wealth, they contribute to the food security of the population, since they are the ones who fulfill the day-to-day needs, as well as contributing to the growth of other sectors of the economy due to the demands of services and inputs that they require to function.
In Chile the majority of the agricultural exploitations are small farms; of the 278,660 farms recorded in the last agricultural census, 165,813 are less than 10 ha, while the exploitations of more than 500 ha (1.63%) concentrate nearly 80% of the total area dedicated to agriculture. In terms of management capacity, approximately 30,000 farms may be classed as modern or traditional companies, thus nearly 250,000 belong to small producers and landholders who have serious problems of land, capital and education.
As in the majority of Latin American countries, in Chile the differences in some indexes of human development are significant between the urban and rural areas, disfavoring the latter, especially in terms of education, health, income level, life expectancy and others. Thus the need for better development of the rural agricultural world is a question of social equity. A better understanding of agricultural productive systems would make it easier to define policies, strategic objectives and lines of action of the governmental and private agencies and institutions associated with agriculture, in order to overcome their limitations and thus reduce the existing inequalities.
In the extreme north of Chile, due to the influence of the Atacama Desert there is a diversity of productive systems with particular characteristics due to the special abiotic features such as precipitation level, temperature, solar radiation, humidity, altitude, topography, soil and water quality, among other factors. The internal functioning of these systems depends not only on the internal structural relations of their components, but also on their interactions with the markets of products, inputs, finances and technical assistance; on government policies, regulations of regional governments and networks of roads, electricity and communications, among other things. Classifying these systems according to their elements and/or common limitations makes it easier for analyses to infer their needs in order to develop.
According to the sources of variation mentioned above, the following is an approximation of the types of production systems in the extreme north from the coast to mountain slopes:
Coastal agricultural production systems with saline-borate irrigation water
These production systems are found in the middle and lower areas of the Río Lluta watershed. They are irrigated with water that has CEw from 2.2-5.3 dS/m and boron concentrations of 16 to 27 mg L-1, depending on the time of year and the part of the river where they are measured. There are also drainage problems, since the river which provides the water also functions as the drain; thus the salinity and boron concentration increase downstream. The presence of a high water table in some sectors of this valley also favors the increase in the salinity at the level of the soil cultivated.
The area has a benign climate which would allow cultivation without restrictions of a wide range of vegetables, tropical and subtropical fruits, except for the quality of the surface and subterranean water.
These systems are at relatively short distances from the urban markets in which the majority of the farmers sell their products. Other farmers also sell their products to intermediaries who transport them from the farms, with or without previous agreements, in order to have the economic resources to finance the crop. Due to their location, it is also easy for these farmers to connect with the financial markets, technical assistance and field workers, among others.
In these systems farmers may grow without restrictions during the entire year alfalfa, beets, onions, garlic, corn cv. Lluteño, asparagus and some flower species such as carnations, wallflowers and limonium, although with some damage in the leaf borders and/or apexes. Other species which are grown with drip irrigation, in spite of having reduced yields, include tomato, sweet pepper, peppers, broccoli and cauliflower. Some vegetables cannot be grown because of their greater sensitivity to salts and boron, such as green beans, cucumbers, carrots, lettuce, melons and watermelon, among others. The only fruit species which has no problems in these productive systems is the date palm; however, there are no commercial orchards of this species.
These systems have the potential for greater agricultural growth, subject to inversions which would separate irrigation water from drainage waters (this would also aid in the control of blood-sucking insects which affect people and livestock), more efficient management of fertigation, management of boron with organic additives and cultivation under anti-vector nets (or simply removing boron from irrigation water with resins), and the incorporation of good agricultural practices, in order to face more efficiently competition from other regions which also cultivate vegetables in the coldest months of the year.
Coastal systems based on mixed cultivation of fruit and vegetables
These systems are found in the watersheds of the Río San José and Río Codpa. The irrigation water quality of these systems is superior to that of the Río Lluta, since the salinity is about 1 dS/m and boron concentration is around 0.9 mgL-1 in the Río San José watershed. The climate of these areas allows vegetable cultivation in the whole year; the principal crops are tomato, green beans, corn, sweet pepper, cucumber and lettuce, among others. Fruits include olive, avocado, citrus, mango and guava, among others.
These are dynamic production systems, especially those in the Río San José watershed of the Azapa valley, in which farmers plan their vegetable crops as a function of the demand of the central area of the country in the coldest months of the year, thus the farm calendar begins at the beginning of autumn. The most important crop is the tomato, thus when farmers use crop rotation, this is subject to the area reserved for tomato. The benign climate is also benign for pests and diseases, which farmers are overcoming by using structures with anti-vector nets which helps them to reduce problems with viruses, minimize the use of pesticides and therefore produce safer products, as well as increasing the temperature a few degrees, which is especially important for the systems in the higher parts of the valley.
Due surely to the interest in tomato cultivation to maximize utilities, some farmers, especially those whose land is adjacent to the slopes of the valley, are expanding their farm limits to these lands. It is estimated that currently 356 ha are occupied by crops of the total of 412 ha listed in the administrative act of the Ministerio de Bienes Nacionales. Others are expanding their limits towards the river bed, filling and leveling the land; this unfortunately is contributing to reduce the biodiversity of the wild flora and fauna. These crops are labor-intensive, and due to the increasing shortage of laborers, most farmers use a sharecropping system. The crops have also increased the foreign labor force, especially Peruvian and Bolivian, which is producing a more organized response to the demand.
In recent years in the Azapa valley important changes are occurring at the level of the area exploited and the labor force, due to the arrival of transnational seed-producing companies interested in being able to extend their activities through the whole year. Because of the nature of the activities of the companies they require an extensive labor force, which is contributing to decrease unemployment in both urban and rural areas. Also, since their interest is restricted to particular crops, mainly corn and soya, they are contributing to change the rural landscape by felling olive and other fruit trees (approximately 80 ha) of those farms which they have bought or rented. They currently have about 300 ha under cultivation. They have also contributed to the increase in the value of the land ($80x106/ ha) and water quotas ($18x106/action), which has triggered the interest of some farmers to sell or rent their land, with the result that both farmers and sharecroppers are migrating to other valleys.
Because the Azapa valley is currently focused on satisfying the demand for vegetables of the center of the country in the winter months, with competition from localities in the V Region, the growth potential of the productive systems in the north must focus on the incorporation of more technology related to cultivation under controlled environments, fertigation, soilless culture and the incorporation of good agricultural and labor practices, in order to obtain products with competitive quality in the markets. Also, in order to achieve these goals farmers must somehow train themselves in farm techniques, organization and management; for example, currently few farmers have a bookkeeping system to aid in decision making. Strengthening these aspects may also give the farmers the opportunity to consider external markets. Although these coastal valleys do not have problems with salinity or boron, and have a climate which allows cultivation of subtropical and some tropical fruits, this area has been neglected except for olives.
Production systems in the steep slopes of the high Andes
These are systems located at 3000 to 5000 m altitude on hills and mountainsides, in which man has constructed terraces to facilitate irrigation and decrease erosion; due to the steepness of the terrain the majority of these terraces are narrow. The cli-mate of the area is Marginal High Desert; annual precipitation varies from 50-200 mm, concentrated in summer months, thus there is no possibility of growing rainfed crops.
The main crop which generates income in the majority of the localities of this area is oregano. To a lesser extent potatoes, corn and faba beans, among others, are also cultivated, but for self-consumption. Corn and faba beans have the advantage that they may be dried and preserved for a long time; potatoes are also preserved by desiccation ("chuño" potatoes); however, this process involves natural exposition to low nocturnal temperatures and high daytime sunlight. These are of vital importance for the farmers, since they provide an important part of their diet. Another crop which is usually present in these cultivation systems is alfalfa, which supports raising sheep, goats and some cattle. There are also some fruit trees such as the "tumbo", prickly pears and apples, but at the level of family orchards.
Vegetables are grown mainly in the terraces, while alfalfa is cultivated mainly in land with more gentle slope. In some cases the terraces are not sufficiently flat, which combined with the irrigation by flooding which is used, slowly erode the soil and thus risk current productivity and the opportunity for future generations to continue to exploit the resource. In some farms the neck of oregano plants is 30 cm above the soil surface. Because of the narrowness of the terraces or their location in steep slopes, or simply from the lack of economic resources, the use of agricultural machinery is practically zero; farmers continue to use manual tools, which has a great impact in the production costs of their crops and makes them less competitive.
Another factor which limits productive growth of these systems is the water. The great majority of the farmers use gravitational flooding irrigation, which in the steep slopes of the terraces is very inefficient. Periodically the producers agree on the order of their turns and irrigation frequency, which usually begins with 8 days and ends with 12 or more days, depending on water availability. Sometimes when the irrigation frequency is too long, farmers take a smaller amount in between their turns for their own family crops. The crop with lowest priority is alfalfa, thus in years with greater water deficit some farmers can only irrigate twice; this explains the low density of this crop in the fields.
A good number of the farmers manage more than one farm; other farms may be rented, loaned or sharecropped; they also have access to community land. The farms are not always located in the same sector, which has some advantages such as reducing frost risks, and disadvantages such as having to herd their animals daily from the town corrals to the farms, which makes the cattle lose energy. Those who do not have donkeys have trouble moving the manure from the stables to the crops, sometimes to the extreme of burning the manure in the stable.
Most of the commercialization of the harvests of these producers is done at the farms; very few sell their products in the agricultural terminal. Since there are few intermediate buyers in this stage of the food chain, the economic relations are somewhat asymmetrical. Because of this, those oregano producers who do not need to sell immediately store their harvest to wait for better prices, which is feasible because of the low humidity in the environment.
To maintain the economy of their agricultural systems some farmers, mainly the youngest ones, improve their income by working outside the farm in labors such as road paving, construction and reparation of canals, reparation of ancient artwork, mining or services, among others. This undoubtedly produces a work overload for the women, who have to assume more responsibility in the exploitation as well as their work in the household and with the education of their children. On occasions, the difficulties in maintaining the structural elements of their systems and lack of secondary education for their children cause these farmers to migrate to urban centers.
The scarce or null use of agrochemicals, the very good quality of the irrigation water in some sectors, the reduced pressure of plagues and diseases, the high radiation and the existence of cultivars of corn and potatoes with particular culinary attributes, as well as the greater aroma which is produced by the oregano grown at these high altitudes, may constitute advantages for the farmers to generate specialized niches for organic products.