• Authors:
    • Agnelli, A.
    • Roggero, P. P.
    • Ledda, L.
    • Porcu, G.
    • Seddaiu, G.
    • Corti, G.
  • Source: Agriculture Ecosystems and Environment
  • Volume: 167
  • Year: 2013
  • Summary: The aim of this study was to assess the impact of different long term soil managements on soil organic matter (SOM) quantity and quality in a semi-arid Mediterranean dehesa-like agro-forestry system (North-East of Sardinia, Italy). Seven soil managements were compared: cork oak forest, pasture under oak trees, open pasture, hay crop under oak trees, open hay crop, grass-covered vineyard and tilled vineyard. Analyses include chemical and spectroscopic (FT-IR) characterization of the humic substances (fulvic acids, humic acids and humin) of the A horizons. Lower amounts of total organic C and humic substances were found in the more disturbed soils such as those of the tilled vineyard, while the other soil managements showed a rather similar pattern for many indices of SOM quality (e.g., HA-C/FA-C, fulvic H/C and humic and fulvic C/N ratios) and for spectroscopic characteristics. These results indicated that the impact of soil management on the humic composition was relatively low for these sub-acid (pH ranging from 5.1 to 6.4) sandy soils under Mediterranean type of climate. The relatively small differences between the forest and the grassland land uses also suggested that the periodical light tillage applied to the grassland did not strongly affect SOM accumulation in the topsoil of this land use. In the oak forest soils, a sharp decrease (-77%) of the organic C from the thin A1 to the A2 horizon was observed, which could constrain the resilience of these soils towards disturbance factors, while the grasslands soils, where the organic C sequestration occurred in a thick horizon, may be more resilient. The compared soil managements revealed to be quite conservative, demonstrating that the traditional agro-silvo-pastoral management practices are effective in maintaining relatively good soil quality traits under semi-arid Mediterranean conditions.
  • Authors:
    • Arena, C.
    • Amato, U.
    • Maglione, G.
    • Polimeno, F.
    • Ottaiano, L.
    • Vitale, L.
    • Di Tommasi, P.
    • Mori, M.
    • Magliulo, V.
  • Source: Plant, Soil and Environment
  • Volume: 59
  • Issue: 11
  • Year: 2013
  • Summary: The effect of the nitrification inhibitor 3,4-dimethylphyrazole phosphate (DMPP) on N-fertilized crop growth and soil N2O emissions were studied at two experimental sites in Southern Italy, characterised by a Mediterranean climate and different soil texture. The experiments were a randomized block design of two treatments: crop fertilized with NH4NO3 (considered the control treatment) or amended with DMPP plus NH4NO3 (considered the DMPP treatment). ANOVA was performed to assess differences between treatments and fertilization periods whereas simple and multiple linear regressions were performed in order to assess the effect of the soil-related independent variables on soil gases emissions. Growth of potato plants fertilized with DMPP-added nitrogen was enhanced compared to control plants, whereas no benefit on maize plants grown during summer was observed. N2O emissions measured from soil to potato after the first fertilization with DMPP-added nitrogen was reduced during winter, but was higher than control after the second fertilizer application in spring, leading to comparable N2O emission factors (EF1) between treatments. In maize N2O emissions and EF1 were lower for DMPP compared to control treatment. The effectiveness of reduction in soil N2O emission was influenced by soil temperature and water-filled pore space (WFPS) in both experimental sites. However, the overall effect of WFPS was contrasting as N2O emissions were decreased in potato and enhanced in maize.
  • Authors:
    • Moriondo,M.
    • Jones,G. V.
    • Bois,B.
    • Dibari,C.
    • Ferrise,R.
    • Trombi,G.
    • Bindi,M.
  • Source: Climatic Change
  • Volume: 119
  • Issue: 3-4
  • Year: 2013
  • Summary: This research simulates the impact of climate change on the distribution of the most important European wine regions using a comprehensive suite of spatially informative layers, including bioclimatic indices and water deficit, as predictor variables. More specifically, a machine learning approach (Random Forest, RF) was first calibrated for the present period and applied to future climate conditions as simulated by HadCM3 General Circulation Model (GCM) to predict the possible spatial expansion and/or shift in potential grapevine cultivated area in 2020 and 2050 under A2 and B2 SRES scenarios. Projected changes in climate depicted by the GCM and SRES scenarios results in a progressive warming in all bioclimatic indices as well as increasing water deficit over the European domain, altering the climatic profile of each of the grapevine cultivated areas. The two main responses to these warmer and drier conditions are 1) progressive shifts of existing grapevine cultivated area to the north-northwest of their original ranges, and 2) expansion or contraction of the wine regions due to changes in within region suitability for grapevine cultivation. Wine regions with climatic conditions from the Mediterranean basin today (e.g., the Languedoc, Provence, Ctes Rhne M,ridionales, etc.) were shown to potentially shift the most over time. Overall the results show the potential for a dramatic change in the landscape for winegrape production in Europe due to changes in climate.
  • Authors:
    • Novara,Agata
    • Gristina,Luciano
    • La Mantia,Tommaso
    • Ruehl,Juliane
  • Source: Geoderma
  • Volume: 193-194
  • Year: 2013
  • Summary: Clarifying which factors cause an increase or decrease in soil organic carbon (SOC) after agricultural abandonment requires integration of data on the temporal dynamics of the plant community and SOC. A chronosequence of abandoned vineyards was studied on a volcanic island (Pantelleria, Italy). Vegetation in the abandoned fields was initially dominated by annual and perennial herbs, then by Hyparrhenia hirta (L.) Stapf, and finally by woody communities. As a consequence, the dominant photosynthetic pathway changed from C-3 to C-4 and then back to C-3. Conversion of a plant community dominated by one photosynthetic pathway to another changes the C-13/C-12 ratio of inputs to SOC. Using the time since abandonment and the shift in belowground delta C-13 of SOC relative to the aboveground delta C-13 plant community, we estimated C-3-C and C-4-C changes during secondary succession. SOC content (g kg(-1)) increased linearly (R-2=0.89 and 0.73 for 0-15 and 15-30 cm soil depth) with the age of abandonment, increasing from 12 g kg(-1) in cultivated vineyards to as high as 26 g kg(-1) in the last stage of the succession. delta C-13 increased in the bulk soil and its three aggregate fractions (> 250,250-25, and < 25 mu m) during succession, but the effect of soil depth and its interaction with succession age were significant only for soil aggregate fractions. Polynomial curves described the change in delta C-13 over the chronosequence for both depths. delta C-13 in the bulk soil had increased from -28 parts per thousand. to -24 parts per thousand. by 35 years after abandonment for both depths but then decreased to -26 parts per thousand. at 60 years after abandonment (corresponding with maturity of the woody plant community). Overall, the results indicate that abandoned vineyards on volcanic soil in a semi-arid environment are C sinks and that C storage in these soils is closely related to plant succession. (C) 2012 Elsevier B.V. All rights reserved.
  • Authors:
    • Martiniello, P.
  • Source: Agricultural Sciences
  • Volume: 3
  • Issue: 1
  • Year: 2012
  • Summary: Agricultural systems based on crop rotations favour sustainability of cultivation and productivity of the crops. Wheat-forage crops rotations (annual winter binary mixture and perennial alfalfa meadow) combined with irrigation are the agronomical techniques able to better exploit the weather resources in Mediterranean environments. The experiment aimed to study the effect of 18 years of combined effect of irrigation and continuous durum wheat and wheat-forage rotations on productivities of crops and organic matter of topsoil. The experiments were established through 1991-2008 under rainfed and irrigated treatments and emphasized on the effect of irrigation and continuous wheat and wheat-forage crop rotations on water use efficiency and sustainability of organic matter. The effect of irrigation increased 49.1% and 66.9% the dry matter of mixture and meadow, respectively. Continuous wheat rotation reduced seed yield, stability of production, crude protein characteristics of kernel and soil organic matter. The yearly gain in wheat after forage crops was 0.04 t (ha yr) 1 under rainfed and 0.07 t (ha yr) -1 under irrigation treatments. The crude protein and soil organic matter of wheat rotations, compared to those of continuous wheat under rainfed and irrigated was increase in term of point percentage by 0.8 and 0.5 in crude protein and 5.1 and 4.4 in organic matter, respectively. The rotations of mixture and meadow under both irrigated treatments increased the point of percentage of organic matter over continuous wheat (9.3.and 8.5 in mixture and 12.5 and 9.5 meadow under rainfed and irrigation, respectively). Irrigation reduce the impact of weather on crop growing reducing water use efficiency (mean over rotations) for dry matter production (15.5 in meadow and 17.5 in mixture [L water (kg dry matter) -1]) and wheat seed yield. The effect of agronomic advantages achieved by forage crops in topsoil expire its effect after three years of continuous wheat rotation.
  • Authors:
    • Paoletti, M. G.
    • Marini, L.
    • Nascimbene, J.
  • Source: Environmental Management
  • Volume: 49
  • Issue: 5
  • Year: 2012
  • Summary: The majority of research on organic farming has considered arable and grassland farming systems in Central and Northern Europe, whilst only a few studies have been carried out in Mediterranean agro-systems, such as vineyards, despite their economic importance. The main aim of the study was to test whether organic farming enhances local plant species richness in both crop and non-crop areas of vineyard farms located in intensive conventional landscapes. Nine conventional and nine organic farms were selected in an intensively cultivated region (i.e. no gradient in landscape composition) in northern Italy. In each farm, vascular plants were sampled in one vineyard and in two non-crop linear habitats, grass strips and hedgerows, adjacent to vineyards and therefore potentially influenced by farming. We used linear mixed models to test the effect of farming, and species longevity (annual vs. perennial) separately for the three habitat types. In our intensive agricultural landscapes organic farming promoted local plant species richness in vineyard fields, and grassland strips while we found no effect for linear hedgerows. Differences in species richness were not associated to differences in species composition, indicating that similar plant communities were hosted in vineyard farms independently of the management type. This negative effect of conventional farming was probably due to the use of herbicides, while mechanical operations and mowing regime did not differ between organic and conventional farms. In grassland strips, and only marginally in vineyards, we found that the positive effect of organic farming was more pronounced for perennial than annual species.
  • Authors:
    • Pannacci, E.
    • Onofri, A.
    • Graziani, F.
    • Tei, F.
    • Guiducci, M.
  • Source: European Journal of Agronomy
  • Volume: 39
  • Year: 2012
  • Summary: Long-term effects of organic (ORG) and conventional low-input (CONV) farming systems on size and composition of weed seedbank were assessed in 2007 in central Italy, in an on-farm experiment set up in 1996. In this experiment, six rotations (R1-R6) were considered, basically consisting on the same crop sequence with different starting points, i.e. (1) legume crop (soybean/field bean/common pea), (2) vegetable crop (pepper/melon), (3) winter cereal (soft/durum wheat), (4) summer cereal (maize) (5) industrial vegetable (processing tomato), (6) winter cereal (soft/durum wheat). All rotations were established both in ORG and in CONV, in strict adherence to EU regulations (ORG: EU reg. 2092/91; CONV: EU reg. 2078/92). Intercrops with green manuring purposes were included in ORG, while weed control was performed mechanically in ORG and chemically/mechanically in CONV. Weed seedbank was determined on 10 soil samples (0-0.30 m depth) in each plot and seeds were directly extracted, identified and counted. In all rotations, the adoption of ORG resulted in a significant increase in weed seedbank density, particularly in the case of summer weed species ( Portulaca oleracea L., Amaranthus retroflexus L. and Chenopodium album L.), which are more competitive and difficult to control in summer crops under organic farming systems in the Mediterranean climates. Small differences between ORG and CONV were found in terms of number of weed species (23 in ORG and 20 in CONV, on average), but the index of diversity in CONV was on average higher than in ORG. Furthermore, the most dominant weeds in CONV represented a lower percentage of total seedbank (40%, 23% and 5%, respectively, for P. oleracea, A. retroflexus and C. album in CONV and 56%, 32% and 4% for the same three weeds in ORG). These results confirm that the wider availability of effective weed control methods in integrated low-input farming systems (CONV) is helpful to maintain a low seedbank size, with a lower dominance structure. However, the adoption of ORG systems based on long rotation cycles, very competitive crops and accurate weed control, especially at the beginning of the ORG management, may be sustainable in the long run, in terms of potential weed infestation levels.
  • Authors:
    • Ercoli, L.
    • Masoni, A.
    • Mariotti, M.
    • Arduini, I.
  • Source: Grass and Forage Science
  • Volume: 67
  • Issue: 2
  • Year: 2012
  • Summary: Intercropping (IC) cereals and legumes could be an option for obtaining forage suitable for ensiling and enabling reduced N fertilization. Two experiments were performed in central Italy with durum wheat ( Triticum durum Desf.) and field bean ( Vicia faba L. var. minor) grown for forage production in IC and as sole crops (SC) with different N rates (20 and 50 kg ha -1) and row ratios (1:1 and 2:1 cereal/legume). The aims were to assess (i) whether IC is a feasible option to reduce N fertilization; (ii) the best combination of practices to obtain forage suitable for ensiling; and (iii) competition/facilitation effects exerted by field bean on durum wheat. Results showed IC allowed fertilizer-N reduction and led to improved forage yield with better quality, compared with SC. Land equivalent ratio indicated a high efficiency of the IC, by up to 26% with respect to SC. Field bean was the dominant species of IC, but N fertilization reduced its competitive ability and enhanced that of wheat. In the intercrop fertilized with 50 kg N ha -1, the proportion of the wheat in the herbage (0.34-0.41 of the total dry matter) was sufficient for ensiling of the forage mass. Field bean exerted both competition and facilitation effects on the cereal. N uptake of durum wheat was greater under IC with beans than as wheat SC.
  • Authors:
    • Olsson, O.
    • Isopi, A.
    • Dimico, A.
  • Source: Credit Research Paper
  • Issue: 12/01
  • Year: 2012
  • Summary: Since its first appearance in the late 1800s, the origins of the Sicilian mafia have remained a largely unresolved mystery. Both institutional and historical explanations have been proposed in the literature through the years. In this paper, we develop an argument for a market structure-hypothesis, contending that mafia arose in towns where firms made unusually high profits due to imperfect competition. We identify the market for citrus fruits as a sector with very high international demand as well as substantial fixed costs that acted as a barrier to entry in many places and secured high profits in others. We argue that the mafia arose out of the need to protect citrus production from predation by thieves. Using the original data from a parliamentary inquiry in 1881-86 on all towns in Sicily, we show that mafia presence is strongly related to the production of orange and lemon. This result contrasts recent work that emphasizes the importance of land reforms and a broadening of property rights as the main reason for the emergence of mafia protection.
  • Authors:
    • Mennone, C.
  • Source: L'Informatore Agrario
  • Volume: 68
  • Issue: 27
  • Year: 2012
  • Summary: in Italian; see: http://www.informatoreagrario.it/BDO/BDO_popupAbstract.asp?D=107647