13/8/21 00:00

Generative Agriculture

From jarillas and chañares to high production systems

Chacra Aapresid in the Irrigated Valleys of North Patagonia (VINPA) has been working for  7 years to transform the region's desert environments into fertile and cultivable areas that  facilitate local productive and economic development. 

Florencia Cappiello (Aapresid Press). Chacra Aapresid in the Irrigated Valleys of North  Patagonia (VINPA) has been working for 7 years to transform the region's desert  environments into fertile and cultivable areas that facilitate local productive and economic  development. The engineer Magali Gutierrez, Technical Manager of the project, said that  the producers disembarked in the area with the aim of developing irrigated productive  systems with projection of scale. "This is an area with very beneficial radiation and  temperature levels for crops, and although it is an arid region, Rio Negro offers quantity  and quality of water.” On the other hand, soils are deficient: poor development, low organic  matter and fertility. There was also no technology development or adapted knowledge. 

Heterogeneity and poor infiltration were serious issues: "in 1 ha there can be between 4 and  5 soil substrates, with different behavior and features. There is considerable microrelief,  which causes the water to accumulate in a very irregular way, generating excesses in some  points and shortages in others," added Sergio González, a producer who is member of the  project. The aim of the project was to develop new soils, which was achieved through  several aspects: specific polycultures for autumn and winter to create abundant cover and  prevent increased salinity. Another aspect was summer irrigation on living cover crops of  foxtail millet, guinea corn and sorghum. In order to deal with the infiltration deficit, a  strategy of irrigation depth of low and high frequency was chosen. 

Allowing the crops to  colonize the soil, the second aim was to achieve a 'bombardment of intense and diverse  roots' that provide residues with C and N. "In 2 to 4 years, it was possible to obtain  profitable yields." Among the most relevant results were a reduction in bulk density, salt  washing, increased C and productivity: “We went from soils that tolerated 1 cow every  15/20 hectares to wheat of 8-10 tons, vetch of 6 tons DM, soybeans of 3.5-4.5 tons and corn  of 12-15 tons," explains Gutierrez. To achieve this, the variables of irrigation, weather,  technology, time and human capital were essential. In turn, Luis Wall, CONICET's  specialist, explained the evolution of soil biology variables that occurred with this  management. "There were great differences in these soils with respect to pristine forests.  

The impact of soil biology management is clear: large increases in microbial diversity,  which is surprising since agriculture normally produces the opposite effect. Another  surprising result is the higher level of interaction in the networks of microbial community  with respect to the forest soil.” We detected fungal/bacterial groups associated with  increased organic matter, aggregate formation, after the improvement of soil health. All of  this was associated to more intense and diverse rotations. “We begin to recognize  components of that black box that is soil biology.”