Browsing by Subject "LOSSES"

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  • Kosunen, Maiju; Kantola, Tuula; Starr, Mike; Blomqvist, Minna; Talvitie, Mervi; Lyytikäinen-Saarenmaa, Päivi (2017)
    Insect herbivore disturbances are likely to intensify as a consequence of climate change. In Finland, outbreaks of the common pine sawfly (Diprion pini L.), which feeds on Scots pine (Pinus sylvestris L.) needles, and resulting damage to forests have already increased. Although drivers of sawfly outbreak dynamics have been investigated, the effects of topography and soil fertility have not been fully elucidated. We studied the effect of elevation, slope and soil properties (carbon and nitrogen contents, C/N ratio, pH, texture and horizon thicknesses) on the defoliation intensity of 28 plots (227-531 m(2)), located in a 34.5 km(2) forested area in eastern Finland suffering from an extended outbreak of D. pini. Plot elevation and slope (relative relief 35 m, maximum elevation 200 m a. s.l.) were derived from a digital elevation model and the soil properties from samples of the humus layer (Of + Oh), (Ah+) E and B horizons of podzol profiles. Defoliation was greater on the more fertile and flatter sites than on less fertile and steeper sites, but independent of elevation. The soil property most strongly correlated to plot mean defoliation was the C/N ratio of the humus layer (Spearman's rho = -0.68). However, logistic modelling showed that the thickness of the (Ah+) E-horizon had the highest classification accuracy in predicting the probability of a plot having moderate to severe (> 20%) defoliation. Our study showed that forest damage caused by D. pini was related to topography and soil fertility. Taking these factors into account could help in understanding the population dynamics of D. pini, in modeling of insect outbreaks and in forest management planning.
  • Sihvonen, Matti; Lintunen, Jussi; Valkama, Elena; Hyytiäinen, Kari (2020)
    We develop a modeling framework, based on discrete-time dynamic optimization, to study the effect of legacy nutrient stores and soil nutrient dynamics on optimal nutrient management and agri-environmental policy in crop production. Three alternative measures are studied to reduce nutrient loss: reduced fertilization, nonlegume catch crop cultivation and gypsum amendment. According to our results, landowner can bring down excessively high phosphorus stocks causing environmental damage within decades, by simultaneous optimization of the nitrogen and phosphorus fertilizers on the economic basis of profit maximization. Our results suggest that nitrogen loss abatement with catch crops is socially optimal, whereas the use of gypsum is well justified as a temporary measure on soils with high soil phosphorus levels. A dynamic tax-subsidy-scheme, which takes into account the current soil nutrient levels and field attributes such as soil texture, can enforce the socially optimal outcome. The welfare losses of the static steady-state-based tax-subsidy-schemes are increasing functions of the legacy nutrient stores and soil's ability to hold nutrients. Recommendations for Resource Managers We develop a modeling framework to study the effect of the legacy nutrient stores and the soil nutrient dynamics on the optimal nutrient management and agri-environmental policy in crop production. Nonlegume catch crop cultivation is a socially optimal long-term measure for nitrogen loss abatement, whereas phosphorus loss abatement with gypsum is socially optimal on soils with high soil phosphorus levels. A dynamic tax-subsidy-scheme, which is adjusted annually according to the soil nutrient stocks, leads to social optimum. Although this can be difficult to implement in practice, it can be useful in the derivation of the simpler, static tax-subsidy-schemes. If a gypsum subsidy is paid for those years, where the soil P level is above the threshold level for the gypsum application, the welfare loss of the static steady-state-based tax-subsidy-schemes is almost zero. Simultaneous adjustment of the N and P fertilizer rates enables the use of simple, static and soil-texture-ignorant tax-subsidy schemes, without a notable social welfare loss
  • Ngau, Laura, D.; Fong, Sim, S.; Khoon, Kho L.; Rumpang, Elisa; Vasander, Harri; Jauhiainen, Jyrki; Yrjälä, Kim; Silvennoinen, Hanna (2022)
    Water table conditions in drained peatlands affect peat decomposition, fluvial carbon and greenhouse gas emissions, and plant growth in oil palm plantations. This study illustrates the spatial heterogeneity of soil moisture profiles in cultivated tropical peat under oil palm plantation and uncultivated secondary forest, using maps. At a study plot under each land use the geographical coordinates of sampling points, tree locations and other features were recorded. Peat soil samples were taken at depths of 0–50 cm, 50–100 cm, 100–150 cm and 150–200 cm, and their moisture contents were determined. Overall, soil moisture content was higher in secondary forest than in oil palm plantation due to land management activities such as drainage and peat compaction in the latter. Significant differences were observed between the topsoil (0–50 cm) and deeper soil layers under both land uses. Soil moisture maps of the study plots interpolated using geographical information system (GIS) software were used to visualise the spatial distributions of moisture content in soil layers at different depths (0–50 cm, 50–100 cm, 100–150 cm, 150–200 cm). Moisture content in the 0–50 cm soil layer appeared to be inversely related to elevation, but the correlation was not statistically significant. On the other hand, there was a significant positive correlation between soil moisture content and the diameters of oil palm trunks. Palm trees with negative growth of trunk diameter were mostly located in subplots which were relatively dry and/or located near drains. The results of this study indicate that soil moisture mapping using GIS could be a useful tool in improving the management of peatland to promote oil palm growth.
  • Rasool, Shahid; Cerchione, Roberto; Salo, Jari; Ferraris, Alberto; Abbate, Stefano (2021)
    Purpose This study aims to examine the role of hunger, environmental, economic, landfill and water shortage concerns as significant dimensions of consumer social awareness marketing in socially responsible plate food consumption. Design/methodology/approach To carry out their purpose, the authors validate the hypothesized model empirically through data from 1,536 households using structural equation modeling (SEM). In particular, the construct measures of the structural model have been tested by confirmatory factor analysis (CFA). Findings The outcome the authors came up with is coherent with the hypothesized model, and it proves a positive relationship of the five dimensions identified on consumer awareness. Moreover, the study results show the crucial role of landfill and water shortage concerns in measuring consumer awareness. Practical implications These findings may be of interest to practitioners, academics and policymakers for socially responsible food consumption guidance and training for planning consumer awareness programs. More in detail, this study offers the indication that the dimensions of the social consumer awareness construct are differing from commercial consumer awareness. Originality/value Even though several previous studies have addressed the concept of consumer awareness concerning product and service purchase decisions, this is one of the first research studies on consumer awareness as a multidimensional construct in social marketing studies domain.
  • Yli-Halla, Markku; Virtanen, Seija; Regina, Kristiina; Österholm, Peter; Ehnvall, Betty; Uusi-Kämppä, Jaana (2020)
    Besides causing acidification, acid sulfate (AS) soils contain large nitrogen (N) stocks and are a potential source of N loading to waters and nitrous oxide (N2O) emissions. We quantified the stocks and flows of N, including crop yields, N leaching, and N2O emissions, in a cultivated AS soil in western Finland. We also investigated whether controlled drainage (CD) and sub-irrigation (CDI) to keep the sulfidic horizons inundated can alleviate N losses. Total N stock at 0-100 cm (19.5 Mg ha(-1)) was smaller than at 100-200 cm (26.6 Mg ha(-1)), and the mineral N stock was largest below 170 cm. Annual N leaching (31-91 kg N ha(-1)) plus N in harvested grain (74-122 kg N ha(-1)) was 148% (range 118-189%) of N applied in fertilizers (90-125 kg N ha(-1)) in 2011-2017, suggesting substantial N supply from soil reserves. Annual emissions of N2O measured during 2 years were 8-28 kg N ha(-1). The most probable reasons for high N2O emission rates in AS soils are concomitant large mineral N pools with fluctuating redox conditions and low pH in the oxidized subsoil, all favoring formation of N2O in nitrification and denitrification. Although the groundwater level was higher in CD and CDI than in conventional drainage, N load and crop offtake did not differ between the drainage methods, but there were differences in emissions. Nitrogen flows to the atmosphere and drainage water were clearly larger than those in non-AS mineral soils indicating that AS soils are potential hotspots of environmental impacts.
  • Tattari, Sirkka; Koskiaho, Jari; Kosunen, Maiju; Lepisto, Ahti; Linjama, Jarmo; Puustinen, Markku (2017)
    Long-term data from a network of intensively monitored research catchments in Finland was analysed. We studied temporal (1981-2010) and spatial variability in nitrogen (N) and phosphorus (P), from 1987 losses, both from agricultural and forestry land. Based on trend analysis, total nitrogen (TN) concentrations increased in two of the four agricultural sites and in most of the forested sites. In agricultural catchments, the total phosphorus (TP) trends were decreasing in two of the four catchments studied. Dissolved P (DRP) concentrations increased in two catchments and decreased in one. The increase in DRP concentration can be a result of reducing erosion by increased non-plough cultivation and direct sowing. In forested catchments, the TP trends in 1987-2011 were significantly decreasing in three of the six catchments, while DRP concentrations decreased significantly in all sites. At the same time, P fertilisation in Finnish forests has decreased significantly, thus contributing to these changes. The mean annual specific loss for agricultural land was on average 15.5 kg ha(-1) year(-1) for N and 1.1 kg ha(-1) year(-1) for P. In the national scale, total TN loading from agriculture varied between 34,000-37,000 t year(-1) and total P loading 2400-2700 t year(-1) These new load estimates are of the same order than those reported earlier, emphasising the need for more efforts with wide-ranging and carefully targeted implementation of water protection measures.
  • McCrackin, Michelle L.; Gustafsson, Bo G.; Hong, Bongghi; Howarth, Robert W.; Humborg, Christoph; Savchuk, Oleg P.; Svanback, Annika; Swaney, Dennis P. (2018)
    While progress has been made in reducing external nutrient inputs to the Baltic Sea, further actions are needed to meet the goals of the Baltic Sea Action Plan (BSAP), especially for the Baltic Proper, Gulf of Finland, and Gulf of Riga sub-basins. We used the net anthropogenic nitrogen and phosphorus inputs (NANI and NAPI, respectively) nutrient accounting approach to construct three scenarios of reduced NANI-NAPI. Reductions assumed that manure nutrients were redistributed from areas with intense animal production to areas that focus on crop production and would otherwise import synthetic and mineral fertilizers. We also used the Simple as Necessary Baltic Long Term Large Scale (SANBALTS) model to compare eutrophication conditions for the scenarios to current and BSAP-target conditions. The scenarios suggest that reducing NANI-NAPI by redistributing manure nutrients, together with improving agronomic practices, could meet 54-82% of the N reductions targets (28-43 kt N reduction) and 38-64% P reduction targets (4-6.6 kt P reduction), depending on scenario. SANBALTS output showed that even partial fulfillment of nutrient reduction targets could have ameliorating effects on eutrophication conditions. Meeting BSAP targets will require addressing additional sources, such as sewage. A common approach to apportioning sources to external nutrients loads could enable further assessment of the feasibility of eutrophication management targets.
  • Kilpua, E. K. J.; Turner, D. L.; Jaynes, A.; Hietala, H.; Koskinen, H. E. J.; Osmane, A.; Palmroth, M.; Pulkkinen, T. I.; Vainio, R.; Baker, D.; Claudepierre, S. (2019)
    We study the response of the outer Van Allen radiation belt during an intense magnetic storm on 15-22 February 2014. Four interplanetary coronal mass ejections (ICMEs) arrived at Earth, of which the three last ones were interacting. Using data from the Van Allen Probes, we report the first detailed investigation of electron fluxes from source (tens of kiloelectron volts) to core (megaelectron volts) energies and possible loss and acceleration mechanisms as a response to substructures (shock, sheath and ejecta, and regions of shock-compressed ejecta) in multiple interacting ICMEs. After an initial enhancement induced by a shock compression of the magnetosphere, core fluxes strongly depleted and stayed low for 4 days. This sustained depletion can be related to a sequence of ICME substructures and their conditions that influenced the Earth's magnetosphere. In particular, the main depletions occurred during a high-dynamic pressure sheath and shock-compressed southward ejecta fields. These structures compressed/eroded the magnetopause close to geostationary orbit and induced intense and diverse wave activity in the inner magnetosphere (ULF Pc5, electromagnetic ion cyclotron, and hiss) facilitating both effective magnetopause shadowing and precipitation losses. Seed and source electrons in turn experienced stronger variations throughout the studied interval. The core fluxes recovered during the last ICME that made a glancing blow to Earth. This period was characterized by a concurrent lack of losses and sustained acceleration by chorus and Pc5 waves. Our study highlights that the seemingly complex behavior of the outer belt during interacting ICMEs can be understood by the knowledge of electron dynamics during different substructures.
  • Peltola, T.; Eremin, V.; Verbitskaya, E.; Härkönen, J. (2017)
    Segmented silicon detectors (micropixel and microstrip) are the main type of detectors used in the inner trackers of Large Hadron Collider (LHC) experiments at CERN. Due to the high luminosity and eventual high fluence of energetic particles, detectors with fast response to fit the short shaping time of 20-25 ns and sufficient radiation hardness are required. Charge collection measurements carried out at the Ioffe Institute have shown a reversal of the pulse polarity in the detector response to short-range charge injection. Since the measured negative signal is about 30-60% of the peak positive signal, the effect strongly reduces the CCE even in non-irradiated detectors. For further investigation of the phenomenon the measurements have been reproduced by TCAD simulations. As for the measurements, the simulation study was applied for the p-on-n strip detectors similar in geometry to those developed for the ATLAS experiment and for the Ioffe Institute designed p-on-n strip detectors with each strip having a window in the metallization covering the p(+) implant, allowing the generation of electron-hole pairs under the strip implant. Red laser scans across the strips and the interstrip gap with varying laser diameters and Si-SiO2 interface charge densities (Q(f)) were carried out. The results verify the experimentally observed negative response along the scan in the interstrip gap. When the laser spot is positioned on the strip p(+) implant the negative response vanishes and the collected charge at the active strip increases respectively. The simulation results offer a further insight and understanding of the influence of the oxide charge density in the signal formation. The main result of the study is that a threshold value of Q(f), that enables negligible losses of collected charges, is defined. The observed effects and details of the detector response for different charge injection positions are discussed in the context of Ramo's theorem.
  • van Thuijl, Hinke F.; Scheinin, Ilari; Sie, Daoud; Alentorn, Agusti; van Essen, Hendrik F.; Cordes, Martijn; Fleischeuer, Ruth; Gijtenbeek, Anja M.; Beute, Guus; van den Brink, Wimar A.; Meijer, Gerrit A.; Havenith, Miek; Idbaih, Ahmed; Hoang-Xuan, Khe; Mokhtari, Karima; Verhaak, Roel G. W.; van der Valk, Paul; van de Wiel, Mark A.; Heimans, Jan J.; Aronica, Eleonora; Reijneveld, Jaap C.; Wesseling, Pieter; Ylstra, Bauke (2014)