Soil Organic Matter Management: The Roles of Residue Quality in C Sequestration and N Supply - Sustainable Management of Soil Organic Matter - page 155

M.Mazzonciniet al. Crop Management Systems to Conserve Soil Fertility

3.8

Crop Management Systems
to Conserve Soil Fertility
After Long-term Setaside
in Southern Italy

M . M AZZONCINI 1 , L . C ROCÈ 2 , P . B ÀRBERI 3 ,
S . M ENINI 1

AND E . B ONARI 1

1
DipartimentodiAgronomiaeGestionedell'Agroecosistema,
UniversitàPisa, Via S. MicheledegliScalzi2, 56124 Pisa;
2
Istitutodi AgronomiaeColtivazioniErbacee,UniversitàReggio
Calabria, Gallina (RC); and 3 DipartimentodiProduzioneVegetale,
UniversitàTuscia,Viterbo, Italy

Introduction

Setting aside land from agricultural production for a long period seems to
reduce the adverse effects of intensive agricultural systems by conserving
biodiversity, reducing soil erosion and restoring soil quality (e.g. increasing
soil organic matter content and metabolic activities). To an extent, the
degree to which this is true is determined largely by agricultural system
management, soil type, initial level of soil organic matter content and
climate (Fullen, 1998; Masciandaro et al ., 1998). When brought back to
cultivation, soil organic matter content usually decreases (Huggins et al .,
1998; Reeder et al ., 1998). In Southern Italy, where climatic conditions
favour soil organic matter mineralization, continuous cropping systems
based upon deep ploughing have brought about a dramatic drop in average
soil organic matter content, whose preservation is crucial in such conditions
in order to sustain future agricultural productivity and environmental
quality. However, soil quality preservation should be matched with accept-
able crop yield and favourable energetic and economic budgets; therefore,
there is a need to devise sustainable agricultural management systems
which would encompass all these objectives. To evaluate the optimum
management options for agricultural land that has lain unproductive for a
long period in accordance with EU policy (reg. 1765/92 and subsequent
modifications that also provide for leaving land uncultivated for periods of
20 years) in Southern Italy, two crop management systems and three crop