Typically a cattle land, most of the chaco is still virgin. With only few asfalth

roads and a vast territory has no easy acccess. One could travel by barge going north or by plane to a private airt strip. Although no further than 7 hours air trip the region is very remote.

The Chaco present very diferent ecosytems within its territory; the south, the closet to the capital Asuncion, is tipically more developed than other areas. Irrigated by the Paraguay river to the right hand side, most of lower and upper Chaco by the river are  prime pastures (natural or artifitial). The areas of the Chaco that borders the States of San Pedro and Concepcion, which combined has at least a ¼ of the total cattle population, are far more developed than other areas. Some are low lands that although very well irrigated will requieres water management systems during high rain seasons; the southern part near the Pilcomayo are less developed.

Water here is often an issue and the infrestructure is very poor, thereafter, prices present lower than other areas, the north has shown intensive activity over the last couple of years. To be precise this particular area is known for his high levels of fertility. Most of that land is similar to the Cerrados in Matto Grosso in Brazil and studies shows that the land and climate conditions are appropriate for ag production. In fact this area is a coninuation of the Matto Grosso cerrados, one the largest and most productive areas of Brasil. Not considered high forest (AMAZON TYPE), the soil is rich in minerals. Areas such Agua Dulce has been farmed already for a couple of years already. Cotton, maize, sugar cane and jatropha are the among the best candidates to fill the extensive areas of northern chco. This area has particularly attracted foreign investment whcih recently has landed large volumes of investment due to the relation between value and price. The northwestern sub-region, bordering Bolivia has certain areas with high salt content present in subsurface water making a severe problem in the sub-region.

The soil is not apt for agricutlure and the rain regime ranges 800 mm; the east, borders with Bolivia and is known by La Patria. Access is very limited and the rain regime is scarce. Prices justfy by its conditions; the central chaco, is the most developed sub-region. Lead by two menonitties urban centers, the central chaco is the heart of the entire region. Two flourishing cities, Filadelfia and Mcal. Estigarribia nurture industries, an airport and all regular services, including financial services outlets and high speed internet conecction.

Extracts of :
The Gran Chaco
by Dr Fernando Riveres
Crop and Grassland Service,
FAO.

Soils of the Chaco

Soils are formed principally from fluvial deposits based on transported material from the rivers ... In addition to the predominantly flat topography, the scarcity of rain results in an arid zone that experiences frequent dust storms and extremely high temperatures. The soil evolved over deep sedimentary deposits that are either neutral or slightly alkaline, with a high level of base saturation (90-100%). There are marked differences between the soils of the eastern and western parts of the region: the eastern soils are predominantly clay with impeded drainage, frequently solodized with a shallow water table. The western soils are more loamy, comprising sandy loams in the far western areas. They have relatively good drainage and vary from low acidic or neutral to slightly alkaline in the surface horizons. The watertable is deep and may have high salinity. Because of the low rainfall, primary minerals and salts are abundant.

The soils are suitable for forestry and pastures and for cultivation in rotations, while perennial crops are grown under irrigation. Fertility in general is high, but availability of water is a limiting factor, as is the resulting salinization from poorly managed irrigation. There are no major restrictions to the use of machinery, necessary for all types of crop production.

As is usual in areas of warm climate with a long dry season, there is a strong flush of available nitrogen with the onset of the rains due to mineralization of the soil organic matter.

Vegetation types The predominant vegetation of the Chaco is open dry woodland with cacti and bromeliads, stretching continuously over large areas, with a grass ground cover. Schinopsis sp. (Anacardiaceae) is the dominant tree. Other typical vegetation types are palm savannahs, savannah parkland, low tree and shrub savannah, with halophytic shrubs on saline patches.

The Paraguayan Chaco has mesophytic vegetation in its eastern (oriental) part where rainfall is higher, varying from 1 000 to 1 300 mm/yr, but changes to xerophytic in the extreme west, where rainfall falls to a maximum of 600 mm/yr. The intermediate central region is described as mesoxerophytic with annual rainfall between 600 and 1 000 mm.

Palm groves: these takes their name from the caranday palm (Copernica alba), which grows in the lowlands, above the marshes, in broad strips. The understorey of the palm groves consists of grasses with weeds and some shrubs. Grazing animals eat the fruits and spread the seeds of the palm, which pass undigested into the faeces. The groves are on footslopes between the higher ground and the swamps. Espartillo-type grassland occupies the higher areas. The main grasses are Sorghastrum agrostoides, Paspalum panciliatum and Paspalum plicatulum. Among the legumes are Desmanthus virgatus, Desmodium incanum, Galactea sp. and Phaseolus lathyroides, all of them well known forages that have been the basis for several commercially-grown forage cultivars in Australia.

Espartillo grasslands: as noted above, these occupy higher ground and are not flooded regularly. The soils are hydromorphic over clay subsoil, though the external drainage is good. The soils are well supplied with phosphorus, calcium and potassium. The following grasses are found: Elionorus latiflorus, Aristida circinalis, Tridens brasiliensis, Paspalum plicatulum, Spartina argentinensis, and Trichloris pluriflora. There are very few herbaceous legumes; Desmanthus virgatus is found occasionally. Trees include Prosopis campestris, P. nigra, P. algarrobilla and Copernica alba.

Thorn forest: this is found in the central and eastern plain, where trees and shrubs dominate over grasses. Soils are mainly alluvial, saline and alkaline saline. Drainage is fair and allows growth of woody perennials such as quebracho colorado (Schinopsis lorentzii), quebracho blanco (Aspidosperma sp.) and palo santo (Bulnesia sarmiento). Also found are vinal (Prosopis ruscifolia) and algarrobilla (P. algarrobilla). Herbaceous forage legumes are rare, e.g. Desmanthus virgatus and P haseolus lathyroides. The grass cover is made up mainly of Elyonurus latiflorus, Aristida adscensionis and Heteropogon contortus. Trichloris trinita is found in low-lying, more humid, areas but does not contribute greatly as livestock feed. The high density of Prosopis makes it difficult for animals to enter the grazing areas. As Prosopis pods are eaten by livestock, undigested seeds are dispersed and add to the spread and invasiveness of the trees.

The potential of the Chaco
The Chaco is land of good potential; while it does have a climate with marked wet and dry seasons, its thermal growing season is long to continuous, and its soils fertile and derived from deep alluviums. The Chaco compares favourably with other areas of the world with similar climates.

an extremely aproximate map of global soil fertility (dark green indicates highest and red lowest fertility), and controversial in some aspects. It does however indicate that the Chaco Paraguayo (except the west) has quite fertile soils.

Northern Chaco - a very approximate map of soil potential.

light blue (A) indicates : very high soil fertility apt for both crops and improved pasture

sand color (B) indicates : good soil fertility apt for both crops and improved pasture

light green (C) indicates : heavy lowland soils of limited ventilation, making good natural pasture, not apt for crops

brown (D) : light sandy soils with little organic matter, very wind erosion prone, limited use for crops and pasture

pink (E) + red (F) : not apt for any agro use

Text extracted from

http://www.ventacamposparaguay.com/agriculturachacoparaguay.htm