• Authors:
    • Traerup,Sara
    • Stephan,Jean
  • Source: Climatic Change
  • Volume: 131
  • Issue: 3
  • Year: 2015
  • Summary: Increasing attention is being given to climate technologies on the international climate change agenda, not least in the agricultural sector and water sectors, and to technologies for adaptation. However investments in technology-based adaptation (seeds, dams, irrigation, etc.) are complicated by the fact that it remains difficult to predict future climate change impacts, especially on a local scale. In addition, evidence for the costs and benefits of implementing adaptation technologies is relatively limited. The analysis presented in this paper shows that there is a large potential for integrating adaptation technologies into the planning and implementation of on-going and future projects. Based on local-level data from a technology needs assessment project in Lebanon, this paper presents two examples of the economic feasibility of implementing adaptation technologies in the agricultural and water sectors. The results show that the technologies can be applied at low cost and with relatively little effort.
  • Authors:
    • Abdullah,A. S.
    • Aziz,M. M.
    • Siddique,K. H. M.
    • Flower,K. C.
  • Source: Agricultural Water Management
  • Volume: 159
  • Year: 2015
  • Summary: We investigated the use of film-forming antitranspirants (AT) to reduce transpiration and alleviate the adverse effects of late-season drought on wheat ( Triticum aestivum L.) growth and yield. Two experiments were conducted in a controlled-temperature glasshouse from April to November 2014, to compare two watering regimes (well watered and water deficit) and three AT treatments (unsprayed control, sprayed before boot swollen and sprayed before anthesis complete). We measured plant water use, transpiration rate, stomatal conductance and photosynthesis. Relative leaf turgor was measured in real time using a non-destructive method of leaf patch clamp pressure. Drought stress reduced daily water use, transpiration rate, stomatal conductance and leaf turgor in wheat plants after about four days. In contrast, these measurements rapidly declined soon after AT application in both well-watered and water-deficit plants. Nevertheless, once soil moisture deficit increased markedly, AT-treated water-deficit plants maintained significantly higher levels of photosynthesis than untreated plants. Drought stress reduced grain yield in unsprayed control plants by more than 40%, compared to well-watered control plants, mainly due to fewer grains per spike. In contrast, drought stress with AT application prior to the most drought-sensitive boot stage reduced yield by only 14%. These results suggest that AT has the potential to improve wheat yields with late-season drought, as is common in semiarid regions; although, more research is required to test the wider applicability of these results in field conditions.
  • Authors:
    • Fiore,A.
    • Dichio,B.
    • Celano,G.
    • Modarelli,A.
    • Palese,A. M.
    • Quinto,G.
    • Pergola,M. T.
    • Xiloyannis,C.
  • Source: Acta Horticulturae
  • Volume: 1084
  • Year: 2015
  • Summary: The most recent and recognised standards for carbon footprint (CFP) ISO 14067:2013 requires the inclusion of land based emissions (CO2 fluxes from soil organic carbon change and field emissions from fertilization) into greenhouse gas accounting. These two categories of emissions are often disregarded from CFP studies of fruit products. In the present paper a simple methodology to include land-based emissions into greenhouse gas (GHG) accounting of fruit product from perennial crops is tested on a case study, and the results compared to experimental measurement from literature in order to evaluate its point of strength and weakness; this methodology is based on IPCC guidelines for national GHG inventories (IPCC, 2006). All fossil (anthropogenic) and biogenic emissions arising from all agricultural operations during orchard life cycle have been accounted according ISO 14067:2013. Fertilization resulted to be the most impacting agricultural operation, together with the production of materials constituting the irrigation pipe system and its supporting structure (metal and cement poles, wire). The most innovative aspect of the tested methodology consists in considering the sink role of soil in fruit orchards managed according to sustainable agronomical practices (increasing of internal and external carbon input to soil). Comparison with measurements data from literature revealed that the simple methodology tested can be improved in order to improve the accuracy of the estimates according to pedoclimatic conditions and crop specificities. © 2015 ISHS.
  • Authors:
    • Plaza,E. H.
    • Navarrete,L.
    • Gonzalez-Andujar,J. L.
  • Source: Agriculture, Systems and Environment
  • Volume: 207
  • Year: 2015
  • Summary: Disturbances have a prominent role in structuring plant communities. However, in agroecosystems, the long-term effect of disturbances on determining trait distributions within weed communities remains little studied. We analyzed the effect of three tillage treatments, which differ in the intensity of soil disturbance, on the mean, the range and the distribution of four response traits within weed communities. We aim to test whether tillage acts as a filter restricting the range and the distribution of response traits within weed communities and leads to reduced response trait diversity or whether tilling may have a diversifying effect, creating opportunities for more phenotypes to coexist and increasing response trait diversity. To test this idea, we used data on weed abundance recorded over 24 years from an experiment in which conventional tillage (CT), minimum tillage (MT) and no-tillage (NT) systems were compared. We selected four response traits, maximum height, specific leaf area (SLA), seed weight and seed output, and computed the community weighted mean (CWM) of each trait, as well as four multi-trait metrics related to a different aspect of functional diversity. We found that soil disturbance increases available niche opportunities for weeds especially in terms of regenerative traits. CT, the greater soil disturbance, leads to a greater range and even distribution of the studied traits and that abundant weed species from CT plots hold more divergent trait values than those from MT and NT plots. Our results may be explained by the idiosyncrasy of our disturbance treatments that affect weed seed placement in the soil layers as well as the stratification and availability of soil nutrients. We also found that NT system selected for lower CWM of seed weight (and higher seed output) than MT and CT systems. NT places weed seeds mostly on the soil surface, where having a large seed output may be necessary to avoid the risk of decay or depredation. Conversely, MT and CT systems offer some advantage to other strategies such as larger seed sizes useful to germinate from depth. CWM of SLA was higher in NT and MT than in CT plots and this could be related to greater soil nutrient content in NT systems. In addition our results showed a general trend over experimental time for weed communities to increase in height (and slightly in SLA and seed production) while reducing in seed size. These features are generally associated with intensive farming systems.
  • Authors:
    • Proietti,P.
    • Federici,E.
    • Fidati,L.
    • Scargetta,S.
    • Massaccesi,L.
    • Nasini,L.
    • Regni,L.
    • Ricci,A.
    • Cenci,G.
    • Gigliotti,G.
  • Source: Web Of Knowledge
  • Volume: 207
  • Year: 2015
  • Summary: A new type of solid oil mill waste (SOMW), produced by latest-generation decanter, and its derived compost were spread on land for three consecutive years in an olive grove to evaluate the soil chemical characteristics, bacterial abundance and community structure, plant growth and production and oil quality. After the third year of the experiment in both treatments, there was no increase in total organic C (TOC) in the upper layer, while a reduction of TOC concentration in the deeper layer was detected. Moreover, in the upper soil layer, the available P increased in both treated soils compared to control while exchangeable K increased only in SOMW treated soil. In both the treated soils, viable counts of different bacteria showed little or no differences compared with the control. Further, PCR-DGGE analysis of the soil bacterial community indicated the presence of a very high biodiversity that was not affected by the long-term treatment with either SOMW and composted-SOMW. The treated soils with both matrices showed an increase in the vegetative activity and olive yield such as a positive effect on oil quality by increasing phenol content. The overall results indicate that both SOMW and its derived-compost can be positively used as soil amendment, thus, contributing to the reduction in the use of chemical fertilizers.
  • Authors:
    • Sanchez-Garcia,M.
    • Alburquerque,J. A.
    • Sanchez-Monedero,M. A.
    • Roig,A.
    • Cayuela,M. L.
  • Source: Bioresource Technology
  • Volume: 192
  • Year: 2015
  • Summary: A composting study was performed to assess the impact of biochar addition to a mixture of poultry manure and barley straw. Two treatments: control (78% poultry manure + 22% barley straw, dry weight) and the same mixture amended with biochar (3% dry weight), were composted in duplicated windrows during 19 weeks. Typical monitoring parameters and gaseous emissions (CO 2, CO, CH 4, N 2O and H 2S) were evaluated during the process as well as the agronomical quality of the end-products. Biochar accelerated organic matter degradation and ammonium formation during the thermophilic phase and enhanced nitrification during the maturation phase. Our results suggest that biochar, as composting additive, improved the physical properties of the mixture by preventing the formation of clumps larger than 70 mm. It favoured microbiological activity without a relevant impact on N losses and gaseous emissions. It was estimated that biochar addition at 3% could reduce the composting time by 20%.
  • Authors:
    • Vaccari,F. P.
    • Maienza,A.
    • Miglietta,F.
    • Baronti,S.
    • Lonardo,S. di
    • Giagnoni,L.
    • Lagomarsino,A.
    • Pozzi,A.
    • Pusceddu,E.
    • Ranieri,R.
    • Valboa,G.
    • Genesio,L.
  • Source: Agriculture, Ecosystems and Environment
  • Volume: 207
  • Year: 2015
  • Summary: Biochar addition to soil is a promising option for climate change mitigation and is recognized to exert beneficial effects on soil fertility. However, recent meta-analysis documented controversial effects on soil-plant interactions and on crop yields response. The data presented in this paper are the results of a field experiment on a processing tomato crop aiming to enhance the knowledge on the real applicability of biochar at farm scale in a high fertility alkaline soil. The effects of two biochar types on soil properties and on quantitative and qualitative parameters of processing tomato were evaluated. Biochar application significantly increased the soil carbon content, the soil cation exchange capacity and the availability of NH 4+, P and K. Moreover, it stimulated plant growth and N, P and base cation contents at harvest, reducing the leaf water potential in the warmer period. These results demonstrate that also intensive cultivations in fertile soil can benefit from biochar amendment.
  • Authors:
    • Watson,James
    • Challinor,Andrew J.
    • Fricker,Thomas E.
    • Ferro,Christopher A. T.
  • Source: Climatic Change
  • Volume: 132
  • Issue: 1
  • Year: 2015
  • Summary: Understanding the relationship between climate and crop productivity is a key component of projections of future food production, and hence assessments of food security. Climate models and crop yield datasets have errors, but the effects of these errors on regional scale crop models is not well categorized and understood. In this study we compare the effect of synthetic errors in temperature and precipitation observations on the hindcast skill of a process-based crop model and a statistical crop model. We find that errors in temperature data have a significantly stronger influence on both models than errors in precipitation. We also identify key differences in the responses of these models to different types of input data error. Statistical and process-based model responses differ depending on whether synthetic errors are overestimates or underestimates. We also investigate the impact of crop yield calibration data on model skill for both models, using datasets of yield at three different spatial scales. Whilst important for both models, the statistical model is more strongly influenced by crop yield scale than the process-based crop model. However, our results question the value of high resolution yield data for improving the skill of crop models; we find a focus on accuracy to be more likely to be valuable. For both crop models, and for all three spatial scales of yield calibration data, we found that model skill is greatest where growing area is above 10-15 %. Thus information on area harvested would appear to be a priority for data collection efforts. These results are important for three reasons. First, understanding how different crop models rely on different characteristics of temperature, precipitation and crop yield data allows us to match the model type to the available data. Second, we can prioritize where improvements in climate and crop yield data should be directed. Third, as better climate and crop yield data becomes available, we can predict how crop model skill should improve.
  • Authors:
    • Cabral, F.
    • Surgy, S.
    • Bichana, A.
    • Pereira, J.
    • Fangueiro, D.
    • Coutinho, J .
  • Source: Research Article
  • Volume: 162
  • Year: 2015
  • Summary: Cattle-slurry (liquid manure) application to soil is a common practice to provide nutrients and organic matter for crop growth but it also strongly impacts the environment. The objective of the present study was to assess the efficiency of cattle-slurry treatment by solid-liquid separation and/or acidification on nitrogen dynamics and global warming potential (GWP) following application to an acidic soil. An aerobic laboratory incubation was performed over 92 days with a Dystric Cambisol amended with raw cattle-slurry or separated liquid fraction (LF) treated or not by acidification to pH 5.5 by addition of sulphuric acid. Soil mineral N contents and NH 3, N 2O, CH 4 and CO 2 emissions were measured. Results obtained suggest that the acidification of raw cattle-slurry reduced significantly NH 3 emissions (-88%) but also the GWP (-28%) while increased the N availability relative to raw cattle-slurry (15% of organic N applied mineralised against negative mineralisation in raw slurry). However, similar NH 3 emissions and GWP were observed in acidified LF and non-acidified LF treatments. On the other hand, soil application of acidified cattle-slurry rather than non-acidified LF should be preferred attending the lower costs associated to acidification compared to solid-liquid separation. It can then be concluded that cattle-slurry acidification is a solution to minimise NH 3 emissions from amended soil and an efficient strategy to decrease the GWP associated with slurry application to soil. Furthermore, the more intense N mineralisation observed with acidified slurry should lead to a higher amount of plant available N and consequently to higher crop yields.
  • Authors:
    • Franklin,D.
    • Bender-Özenç,D.
    • Özenç,N.
    • Cabrera,M.
  • Source: Soil Science Society of America Journal
  • Volume: 79
  • Issue: 5
  • Year: 2015
  • Summary: composts and soil conditioners may be useful soil amendments to provide organic matter as well as nutrients such as n and P, but net n mineralized and P released can vary greatly among materials. consequently, it is important to identify the material characteristics that control these processes. Furthermore, the magnitude of these processes may be affected by particle size. we conducted two laboratory studies at 30°c to: (i) identify variables that can be used to estimate n mineralized and Mehlich-1 P released from 14 composts and soil conditioners; and (ii) evaluate net n mineralized from three size fractions (<1.0 mm, 1.0-2.0, and 2.0-4.0 mm) of five different composts. organic n content and c/n ratio explained 83% of the variability in the amount of net n mineralized or immobilized per unit of material from the 14 composts or conditioners in 214 d. similarly, organic n content and total P content explained 99% of the variability in the amount of Mehlich-1 P released per unit of material. in the study with size fractions, we found that larger size fractions (1-4 mm) mineralized more n (4% of applied n) than the 0-to 1-mm size fraction (0.5%). these results indicate that sieving composts to obtain specific size fractions may affect the rate of n mineralization. © Soil Science Society of America, 5585 Guilford Rd., Madison WI 53711 USA. All Rights reserved.