• Authors:
    • Silva, E. de O.
    • de Carvalho, C. A. C.
    • Bezerra, M. A.
  • Source: Revista Caatinga
  • Volume: 27
  • Issue: 1
  • Year: 2014
  • Summary: Over the past few years, the increased use of fossil fuels as well as the unsustainable use of land, through the reduction of native forests has increased the greenhouse gas emissions, contributing definitively to the rise in temperature on earth. In this scenario, two environmental factors, directly related to the physiology of crop production, are constantly being changed. The first change is the increase in the partial pressure of carbon dioxide (CO 2), which directly affects photosynthetic efficiency and the associated metabolic processes. The other change is the temperature increase which affects all the physiological and metabolic processes mediated by enzymes, especially photosynthesis and respiration. Therefore, this review aims to discuss the main effects caused by increased CO 2 pressure and the temperature rise in the physiology, productivity and post-harvest quality of plants with photosynthetic metabolism C3, C4 and CAM. Based on physiological evidence, the increased atmospheric CO 2 concentration will benefit net photosynthesis, stomatal conductance and the transpiration of C3 plants, however in hot, dry and saline environments, the C4 and CAM species present an advantage by having low photorespiration. Studies show controversial conclusions about the productivity of C3 and C4 plants, and the quality of their fruits or grains under different CO 2 concentrations or high temperatures. Thus, there is a need for more testing with C3 and C4 plants, besides of more research with CAM plants, in view of the low number of experiments carried out in this type of plants.
  • Authors:
    • Baudino, C.
    • Peano, C.
    • Girgenti, V.
    • Tecco, N.
  • Source: Science of the Total Environment
  • Volume: 473
  • Year: 2014
  • Summary: In this study, we analysed the environmental profile of the strawberry industry in Northern Italy. The analysis was conducted using two scenarios as reference systems: strawberry crops grown in unheated plastic tunnels using currently existing cultivation techniques, post-harvest management practices and consumption patterns (scenario I) and the same strawberry cultivation chain in which some of the materials used were replaced with bio-based materials (scenario 2). In numerous studies, biodegradable polymers have been shown to be environmentally friendly, thus potentially reducing environmental impacts. These materials can be recycled into carbon dioxide and water through composting. Many materials, such as Mater-BI (R) and PLA (R) are also derived from renewable resources. The methodology chosen for the environmental analysis was a life cycle assessment (LCA) based on a consequential approach developed to assess a product's overall environmental impact from the production system to its usage and disposal. In the field stage, a traditional mulching film (non-biodegradable) could be replaced with a biodegradable product. This change would result in waste production of 0 kg/ha for the bio-based product compared to 260 kg/ha of waste for polyethylene (PE). In the post-harvest stage, the issue addressed was the use and disposal of packaging materials. The innovative scenario evaluated herein pertains to the use of new packaging materials that increase the shelf life of strawberries, thereby decreasing product losses while increasing waste management efficiency at the level of a distribution platform and/or sales outlet. In the event of product deterioration or non-sale of the product, the packaging and its contents could be collected together as organic waste without any additional processes because the packaging is compostable according to EN13432. Scenario 2 would achieve reductions of 20% in the global warming potential and non-renewable energy impact categories. (C) 2013 Elsevier B.V. All rights reserved.
  • Authors:
    • Villalobos, P.
    • Gabriela Almeida, M.
    • Iriarte, A.
  • Source: Science of the Total Environment
  • Volume: 472
  • Year: 2014
  • Summary: Nowadays, the new international market demands challenge the food producing countries to include the measurement of the environmental impact generated along the production process for their products. In order to comply with the environmentally responsible market requests the measurement of the greenhouse gas emissions of Ecuadorian agricultural goods has been promoted employing the carbon footprint concept Ecuador is the largest exporter of bananas in the world. Within this context, this study is a first assessment of the carbon footprint of the Ecuadorian premium export banana (Musa AAA) using a considerable amount of field data. The system boundaries considered from agricultural production to delivery in a European destination port The data collected over three years permitted identifying the hot spot stages. For the calculation, the CCaLC V3.0 software developed by the University of Manchester is used. The carbon footprint of the Ecuadorian export banana ranged from 0.45 to 1.04 kg CO2-equivalent/kg banana depending on the international overseas transport employed. The principal contributors to the carbon footprint are the on farm production and overseas transport stages. Mitigation and reduction strategies were suggested for the main emission sources in order to achieve sustainable banana production. (C) 2013 Elsevier B.V. All rights reserved.
  • Authors:
    • Andren, O.
    • Zhao, X.
    • Luo, Y.
  • Source: Acta Agriculturae Scandinavica Section B-Soil and Plant Science
  • Volume: 64
  • Issue: 3
  • Year: 2014
  • Summary: Soil organic carbon (SOC) is a major source/sink in atmospheric carbon balances. Farmland usually has a high potential for carbon dioxide (CO2) uptake from the atmosphere, but also for emission. Data from different areas are valuable for global SOC calculations and model development, and a survey of 108 agricultural fields in Lanzhou, China was performed. The fields were grouped by: cropping intensity (3 levels), cropping methodology (3), and crop species (10). Intensive cropping (two or more crops per year, typically vegetables), moderate (annuals in monoculture: wheat, maize, potato, melons), and extensive (orchards, lily [Lilium brownii] fields, fallow) were the intensity classes; and open field, greenhouse field, and sand-covered field (10-20 cm added on top of the topsoil) were the three methodologies. SOC concentration, pH, electrical conductivity, and soil bulk density were measured, and SOC mass (gm(-2) 0-20 cm depth) was calculated. SOC concentration was high in cauliflower, wheat, leaf vegetables, and fruit vegetables; moderate in potato, fallow (3-5 years), tree orchards, and melons; while low in lily and maize fields, and differences in SOC mass followed the same pattern. SOC concentration and mass were lowest in the extensive fields while moderate and intensive fields showed higher values. Soil bulk density in open fields was significantly lower than those in greenhouse and sand-covered fields. The climate-induced soil activity factor r(e_clim) was calculated, compared with European conditions, and was fairly similar to those in central Sweden. Other factors behind the measured results, such as the influence of initial SOC content, manure addition, crops, etc., are discussed.
  • Authors:
    • Percival, D.
    • Dias, G.
  • Source: Acta Horticulturae, International Society for Horticultural Science
  • Issue: 1017
  • Year: 2014
  • Summary: The amount of energy and greenhouse gas emissions involved in the production of wild blueberries was examined from 2005 to 2008. Typical production practices including mowing, agrochemical applications and use of a double headed harvester resulted in energy and greenhouse gas emissions of 1,398 MJ and 80.7 kg CO 2 per 1,000 kg of berries produced. Inclusion of energy intensive management practices including the use of oil-fired burners and diesel powered supplementary irrigation systems increased total energy consumption and fossil fuel production to values of 7,200 MJ and 239.7 kg CO 2 per 1,000 kg of berries produced. Agrochemical manufacturing, transportation and application accounted for 73.7% of the energy required for the "typical" production system. Therefore, results from this study illustrate the variability in energy use and carbon production that can occur in wild blueberry production and the ongoing need to diligent with the development of environmentally sustainable management technologies.
  • Authors:
    • Karlik, J. F.
    • Angevine, W. M.
    • Brioude, J.
    • Park, J. H.
    • Weber, R.
    • Ford, T. B.
    • Fares, S.
    • Ormeno, E.
    • Gentner, D. R.
    • Goldstein, A. H.
  • Source: Atmospheric Chemistry and Physics
  • Volume: 14
  • Issue: 11
  • Year: 2014
  • Summary: Agriculture comprises a substantial, and increasing, fraction of land use in many regions of the world. Emissions from agricultural vegetation and other biogenic and anthropogenic sources react in the atmosphere to produce ozone and secondary organic aerosol, which comprises a substantial fraction of particulate matter (PM2.5). Using data from three measurement campaigns, we examine the magnitude and composition of reactive gas-phase organic carbon emissions from agricultural crops and their potential to impact regional air quality relative to anthropogenic emissions from motor vehicles in California's San Joaquin Valley, which is out of compliance with state and federal standards for tropospheric ozone PM2.5. Emission rates for a suite of terpenoid compounds were measured in a greenhouse for 25 representative crops from California in 2008. Ambient measurements of terpenoids and other biogenic compounds in the volatile and intermediate-volatility organic compound ranges were made in the urban area of Bakersfield and over an orange orchard in a rural area of the San Joaquin Valley during two 2010 seasons: summer and spring flowering. We combined measurements from the orchard site with ozone modeling methods to assess the net effect of the orange trees on regional ozone. When accounting for both emissions of reactive precursors and the deposition of ozone to the orchard, the orange trees are a net source of ozone in the springtime during flowering, and relatively neutral for most of the summer until the fall, when it becomes a sink. Flowering was a major emission event and caused a large increase in emissions including a suite of compounds that had not been measured in the atmosphere before. Such biogenic emission events need to be better parameterized in models as they have significant potential to impact regional air quality since emissions increase by several factors to over an order of magnitude. In regions like the San Joaquin Valley, the mass of biogenic emissions from agricultural crops during the summer (without flowering) and the potential ozone and secondary organic aerosol formation from these emissions are on the same order as anthropogenic emissions from motor vehicles and must be considered in air quality models and secondary pollution control strategies.
  • Authors:
    • Lu, S.
    • Zhang, F.
    • Chen, Q.
    • Wang, J.
    • Ren, T.
  • Source: PLoS ONE
  • Volume: 9
  • Issue: 5
  • Year: 2014
  • Summary: With the goal of improving N fertilizer management to maximize soil organic carbon (SOC) storage and minimize N losses in high-intensity cropping system, a 6-years greenhouse vegetable experiment was conducted from 2004 to 2010 in Shouguang, northern China. Treatment tested the effects of organic manure and N fertilizer on SOC, total N (TN) pool and annual apparent N losses. The results demonstrated that SOC and TN concentrations in the 0-10cm soil layer decreased significantly without organic manure and mineral N applications, primarily because of the decomposition of stable C. Increasing C inputs through wheat straw and chicken manure incorporation couldn't increase SOC pools over the 4 year duration of the experiment. In contrast to the organic manure treatment, the SOC and TN pools were not increased with the combination of organic manure and N fertilizer. However, the soil labile carbon fractions increased significantly when both chicken manure and N fertilizer were applied together. Additionally, lower optimized N fertilizer inputs did not decrease SOC and TN accumulation compared with conventional N applications. Despite the annual apparent N losses for the optimized N treatment were significantly lower than that for the conventional N treatment, the unchanged SOC over the past 6 years might limit N storage in the soil and more surplus N were lost to the environment. Consequently, optimized N fertilizer inputs according to root-zone N management did not influence the accumulation of SOC and TN in soil; but beneficial in reducing apparent N losses. N fertilizer management in a greenhouse cropping system should not only identify how to reduce N fertilizer input but should also be more attentive to improving soil fertility with better management of organic manure.
  • Authors:
    • Cocco, S.
    • Dixon, L.
    • Trumbore, S. E.
    • Bol, R.
    • Agnelli, A.
    • Corti, G.
  • Source: Agriculture Ecosystems and Enviroment
  • Volume: 193
  • Year: 2014
  • Summary: To examine the effects of vineyard soil management on soil C and N content and quality, we studied harrowed and grass-covered vineyards on a soil developed on plio-pleistocene, marine sediments. A soil naturally covered by grasses adjacent to the vineyards served as control. To reach this goal, we assessed (1) the distribution of C and N and their 13C and 15N signatures in different soil organic matter pools, (2) the amount of C and N as live and dead vine fine roots and their 13C, 15N and 14C signatures, and (3) the stocks of C and N forms accumulated at two soil-depth intervals (0-50 and 50-100 cm). Independent of the soil management, the vines increased the total organic C and total N content in the deeper soil horizons because of root turnover and rhizodeposition processes. In the upper horizons, a greater organic matter accumulation was fostered by the presence of the grass cover and the absence of tillage. The grass cover favoured the organic C storage mainly in the form of particulate and highly stabilised organic matter (humic acids and humin), and reduced the soil N content by plant uptake, whereas the harrowing produced a greater abundance of fulvic acids, which were mainly ascribed to oxidative processes enhanced by the soil tillage. In both vineyard soils, decaying vine roots represented an important source of organic C and N, especially in the deepest horizons. Indeed, isotope analyses revealed a more intense degradation of the dead vine roots in the deeper soil portion, where they likely constituted the main substrate for soil microorganisms. In the deepest horizons of the grass-covered vineyard, the greater mean residence time of the decaying vine roots and the lower root production were attributed to the easily available energetic substrates supplied by grass root turnover and rhizodeposition, which were preferentially used by microorganisms. This fact fostered a larger C accumulation in the grass-covered than in the harrowed vineyard.
  • Authors:
    • Sanginga, P.
    • Amede, T.
  • Source: JOURNAL OF SOIL AND WATER CONSERVATION Pages:
  • Volume: 69
  • Issue: 4
  • Year: 2014
  • Authors:
    • Porqueddu, C.
    • Pulina, P.
    • Nieddu, G.
    • Mercenaro, L.
  • Source: Agriculture Ecosystems and Environment
  • Volume: 192
  • Year: 2014
  • Summary: In the Mediterranean area, the use of cover crops in vineyards is still debated and the results of the few scientific experiments considering the influence of cover crop on grapevine are often conflicting. This work aims at providing useful indications on sustainable management for irrigated vineyards growing in a hot and dry region. A five year study was carried out in NW Sardinia, Italy, in a 8 year old vineyard cv. Carignano. To evaluate interactions between grapevine and cover crop as well as the economic impact of intercropping, soil tillage (T1) was compared with 4 inter-row treatments: natural covering (T2), complex commercial grass-legume mixture (T3), simple experimental grass-legume mixture (T4) and perennial grass Dactilys glomerata cv Currie (T5). During the five years of the experiment, the mixtures have ensured a higher level of soil covering compared to the other treatments. Moreover, the covering and the contribution to the dry matter yield for every component of the mixtures changed drastically with an increased presence of D. glomerata. Compared to the soil tillage, the cover crops reduce the vigor but does not affect yield. Regarding fruit quality, only the perennial grass influenced positively the amount of total anthocyanins. The cost analysis has not evidenced strong differences among treatments or limiting factors for growers related to the use of cover crop in vineyards.