Effectiveness of the GAEC standard of cross compliance Crop rotations in maintaining organic matter levels in soils

Abstract

Our study was conducted in the framework of EFFICOND project, with the aim of evaluating the environmental effectiveness of GAEC (Good Agricultural and Environmental Conditions) standards with particular focus to the maintenance of soil organic matter (SOM) levels through the appropriate crop rotation. The study analyzed the effect of crop rotation on the build-up of soil organic matter in three different areas of Italy, located in the North (Lodi), Centre (Fagna, Firenze) and South (Foggia) of Italy, characterized by different climate, soil, and cropping systems. In the two experiments conducted in the South of Italy, in a dry Mediterranean climate, the stock of C was kept steady in most of the rotations compared with the monoculture of durum wheat. In such environment, with very dry and hot summers, introducing a year of fallow seems to improve SOM content, but these data need further investigation. In the Centre of Italy (Fagna), with less extreme climate than in Foggia, the effect of rotation compared to the monoculture of maize is negligible, but investigation on the soil organic matter composition, showed that in the rotation the SOM appeared to be more stable and, in the long term, probably more resistant to degradation. Eventually, experiments conducted in the North of Italy, showed that the monoculture, despite the application of FYM (Farm Yard Manure) or semi-liquid manure, led to a decrease of SOM. To an increase of the rotation complexity, corresponded an increase in the stock of C in soil. Summarizing, results showed that crop rotation could guarantee the maintenance of SOM level, given that the input of C to the soil is maintained at a good level or, in other word, that productivity of the system is high. Other practices such as conservation tillage, appropriate management of residues, and manure application could enhance the positive effect of rotations. Moreover, preliminary investigation of soil microbial diversity, suggests the positive effect of rotations on soil biological fertility

Evaluating the impact of increasing temperatures on changes in Soil Organic Carbon stocks: sensitivity analysis and non-standard discrete approximation

“…At first, we replace T emp(t) and Acc(t) with their averaged values, T emp (1) and Acc (1) in the interval ]t 0 + T , t 0 + 2T ] so that ρ(t) can be approximated by ρ (1) (r) := k a (T emp (1) )k b (Acc (1) )k c (r), where k c (r) is given in Eq. 7.…”

“…, we define the autonomous counterpart of the model (16) in the first year as follows: (1) (r)A c + ϑ (1) a (g) , c(t 0 + T ) = 0, (17) for t ∈]t 0 + T , t 0 + 2T ], where 2…”

Soil organic carbon dynamics in typical durum wheat-based crop rotations of Southern Italy

“…and durum wheat in rotation with irrigated summer crops [mainly processing tomato (T); Solanum lycopersicum L.] are the most common crop rotations. Cropping systems frequently include one year of fallow, and organic fertilisers are not applied to arable crops (Borrelli et al, 2011;Farina et al, 2013). Table 1 shows the main agronomic practices, currently used by farmers for durum wheat and tomato crops.…”

“…So far, semi-arid areas of Southern Italy are dominated by cropping systems mostly oriented on winter cereals-based rotations, such as continuous durum wheat (Triticum durum Desf. ), durum wheat-summer irrigated crops, forage-based systems, and mixed succession with bare fallow (Borrelli et al, 2011;Martiniello, 2011). In these agroecosystems, SOC level is quite low due to soil degradation processes.…”

Factors affecting soil organic matter conservation in Mediterranean hillside winter cereals-legumes cropping systems

“…One of the main EU objectives to preserve soil quality is by maintaining a high level of SOM. However, only a few studies have analysed and proved the effectiveness of these measures, especially in hilly and marginal agricultural systems, characterised by poorer crops (Agnoletti et al, 2011;Borrelli et al, 2011). In these areas, the studies available were mainly made in the late 1990s (Bonari et al 1999;De Falco et al, 2000), while recent ones have focused on more intensive or specialised systems Fumagalli et al, 2011).…”