status and priorities of soil management in peru - julio alegre

STATUS AND PRIORITIES OF SOIL MANAGEMENT IN PERU

TECHNICAL WORKSHOP: “MANAGING LIVING SOILS”

5-7 December 2012, FAO, Rome, Italy

JULIO ALEGRE

Professor: Universidad Nacional Agraria La Molina, Perú

jalegre@lamolina.edu.pe

OUTLINE • OVERVIEW

• LAND USE SYSTEMS

• STATUS OF SOIL RESOURCES

• PRIORITIES OF SOIL MANAGEMENT.

COAST

JUNGLE

HIGHLAND

NO APPROPIATE AREAS TO EXPAND THE CROPPING AREA

Deforestation for death fences: 500 trees/year

AGRICULTURE

SCIENCE OF TERRACES

ESTABILIZATION OF SLOPES

CHANNEL FOR

IRRIGATION h = 1 m

z = 15 - 30%

d >= 2 m

ORGANIZATION AND COMMUNITY WORKTO STABLIZE SLOPES

TERRACES OF SLOW FORMATION

Valle del Colca - Arequipa

Isla de Taquile - Puno

Andenes de Chacawira - Tacna

Andenes de Qalaqala - Tacna

Andenes de Carania en Yauyos - Lima

Andenes de Laraos en Yauyos - Lima

Andenes de Cuchumbaya - Moquegua

Andenes de Ollantaytambo - Cusco

AGROFORESTRY

150,000 ha/year of deforestation with slash and burn system

ULTISOL of upland areas

Risk of physical and chemical degradation

Cedrelinga cataeniformis

Colubrina glandulosa Bactris gasipaes

Inga edulis

Centrosema macrocarpum

Soil Macrofauna

Use of the earthworm Pontoscolex coretroturus as an indicator of soil compaction in pastures (Julio Alegre)

No grazingreo Grazing 3 a/ha

Grazing 6a/ha

Grazing 12 a/ha Natural pasture

overgrazing

Runoff and soil erosion in rice cropping and alley cropping in Yurimaguas, Perú

Treatments mean of 5 years Runnoff (mm) rice alone 414 alley cropping 60 EE 15 Soil Erosion (t ha–1) rice alone 69 alley cropping 5 EE 3

Source : Alegre and Rao (1996) EE = Mean standar error

Land use systems of different ages

Car

bon

in s

yste

m (t

ha

-1)

0 50

100 150 200 250 300 350 400 450 500

C in soil (1 m depth)

C in biomass

SOIL MANAGEMENT PRIORITIES PHYSICAL

LOW SCALE MAPS FOR SOIL SURVEY RECOVERING DEGRADED SOILS (SALINITY, ERODED,

DEFORESTATION) RECOVERING INCA TERRACES INTENSIVE SUSTAINABLE MANAGEMENT OF EXISTING

DEFORESTATED AREAS AGROFORESTRY SYSTEMS ORGANIC AGRICULTURE

SOCIO-ECONOMIC AND POLICIES: LAND TENURE LAWS FOR SOIL CONSERVATION INSENTIVES ENVIRONMENTAL SERVICES

Thank you for your attention