Records 1 - 20 / 3692
Linking oral processing behavior to bolus properties and dynamic sensory perception of processed cheeses with bell pepper pieces
Aguayo-mendoza, Monica G. ; Chatonidi, Georgia ; Piqueras-fiszman, Betina ; Stieger, Markus - \ 2021
Food Quality and Preference 88 (2021). - ISSN 0950-3293
The addition of food particles to food matrices is a convenient approach that allows to steer oral behavior, sensory perception and satiation. The aim of this study was to determine the influence of physical-chemical properties of heterogenous foods on oral processing behavior, bolus properties and dynamic sensory perception. Bell pepper gel pieces varying in fracture stress and concentration were added to processed cream cheese matrices differing in texture. Addition of bell pepper gel pieces to processed cheeses increased consumption time, decreased eating rate and led to harder and less adhesive bolus with more saliva incorporated. Addition of bell pepper gel pieces to processed cheeses decreased dominance rate and duration of creaminess, smoothness, melting and dairy flavor and increased graininess and bell pepper flavor. Increasing fracture stress of bell pepper gel pieces from 100 to 300 kPa resulted in longer consumption time and lower eating rate. For hard/non-adhesive processed cheese matrices increasing gel pieces fracture stress lead to a boli with larger particles and more saliva. These changes were accompanied by decreased dominance perception of creaminess and bell pepper flavor and increased dominance of graininess. Increasing the concentration of bell pepper gel pieces from 15 to 30% did not affect oral behavior but led to the formation of harder and less adhesive bolus with larger particles and less saliva that were perceived with reduced dominance of creaminess, meltiness and dairy flavor while dominance of graininess and bell pepper flavor increased. Changing the texture of the cheese matrix from soft/adhesive to hard/non-adhesive decreased consumption time, increased eating rate, did not influence bolus properties and decreased dominance rate of creaminess, smoothness and melting sensations. Number of chews and total consumption time were positively correlated with saliva content of the bolus, number of bolus particles, bolus hardness, dominance of firmness, chewiness and graininess. We conclude that the modification of physical-chemical properties of processed cheeses and embedded bell pepper gel pieces can be a strategy to steer oral behavior and bolus properties which consequently determine dynamic sensory perception.
Cross-comparison of last glacial radiocarbon and OSL ages using periglacial fan deposits
Palstra, Sanne W.L. ; Wallinga, Jakob ; Viveen, Willem ; Schoorl, Jeroen M. ; Berg, Meindert van den; Plicht, Johannes van der - \ 2020
Quaternary Geochronology 61 (2020). - ISSN 1871-1014
AMS - Fan deposits - OSL - Radiocarbon - Weichselian
Two cores from a Weichselian periglacial alluvial fan were dated using 14C and OSL, to verify the reliability of both methods and check the upper dating limit of the 14C method. Both dating methods yielded a similar chronology for core Eerbeek-I, with infinite 14C dates for the lower part where OSL dates indicated ages of over 45 ka. Finite 14C dates were obtained throughout the core for Eerbeek-II, despite stratigraphic and OSL evidence suggesting ages beyond 14C limits. Apparently, additional chemical pre-treatment to remove younger carbon fractions did not work adequately for samples from this core. We hypothesize that this may be related to a larger influence of younger-age humin fractions in the mainly sandy Eerbeek-II deposits compared to those buffered by a thick peat layer of Eerbeek-I. We suggest that (local) stratigraphy, percolation and humification processes may impact 14C ages of organic deposits more than commonly assumed, and should receive more attention. In addition, we introduce a new method to assess robustness and validity of OSL dates and demonstrate the applicability of OSL dating methods in this setting. Our results highlight that the 14C method requires additional verification methods, such as OSL, for deposits older than 30 ka.
Composting dairy cattle feces at Indonesian small-scale dairy farmsa : results of a composting trial in Lembang Sub-District, West Java
Sefeedpari, Paria ; Vries, Marion de; Buisonjé, Fridtjof de; Suharyono, Deni ; Wouters, Bram ; Zahra, Windi Al - \ 2020
Wageningen : Wageningen Livestock Research (Wageningen Livestock Research report 1262) - 25
The aim of this study was to evaluate effects of composting different ratios of fresh dairy cow feces and amendment material on the composition and the cost price of compost. To this end, mass balance, nutrients losses and the costs of composting were analysed in two composting trials with different ratios of cattle feces to dry amendment (‘postal’, i.e. broiler manure mixed with bedding material) in a practical farm and experimental farm in Lembang Sub-District, West Java, Indonesia. Results showed that composting reduced the weight of input materials and increased the dry matter content, thereby increasing the concentration of nutrients (total nitrogen (N) and phosphate (P)) in the final compost product compared to the initial mixture. Much N was lost during composting, particularly mineral N. Extending the composting period to eight weeks further increased the DM content and resulted in a more stable compost. Using more amendment material (postal) in the initial mixture or extending the composting period, however, led to a higher cost price of compost. It was concluded that reducing the amount of amendment material (postal) and shortening the length of the composting period can reduce the cost price of compost, but may affect the quality of the final compost product. Results showed larger differences between farms than between ratios of cow feces and amendment material, suggesting that compost management practices play an important role.
Characterizing the structure of aerobic granular sludge using ultra-high field magnetic resonance
Kirkland, Catherine M. ; Krug, Julia R. ; Vergeldt, Frank J. ; Berg, Lenno van den; Velders, Aldrik H. ; Seymour, Joseph D. ; Codd, Sarah L. ; As, Henk Van; Kreuk, Merle K. de - \ 2020
Water Science and Technology 82 (2020)4. - ISSN 0273-1223 - p. 627 - 639.
Despite aerobic granular sludge wastewater treatment plants operating around the world, our understanding of internal granule structure and its relation to treatment efficiency remains limited. This can be attributed in part to the drawbacks of time-consuming, labor-intensive, and invasive microscopy protocols which effectively restrict samples sizes and may introduce artefacts. Time-domain nuclear magnetic resonance (NMR) allows non-invasive measurements which describe internal structural features of opaque, complex materials like biofilms. NMR was used to image aerobic granules collected from five full-scale wastewater treatment plants in the Netherlands and United States, as well as laboratory granules and control beads. T1 and T2 relaxation-weighted images reveal heterogeneous structures that include high- and low-density biofilm regions, water-like voids, and solid-like inclusions. Channels larger than approximately 50 μm and connected to the bulk fluid were not visible. Both cluster and ring-like structures were observed with each granule source having a characteristic structural type. These structures, and their NMR relaxation behavior, were stable over several months of storage. These observations reveal the complex structures within aerobic granules from a range of sources and highlight the need for non-invasive characterization methods like NMR to be applied in the ongoing effort to correlate structure and function.
Crowd-Based Observations of Riverine Macroplastic Pollution
Emmerik, Tim van; Seibert, Jan ; Strobl, Barbara ; Etter, Simon ; Oudendammer, Tijmen den; Rutten, Martine ; Ab Razak, Mohd Shahrizal bin; Meerveld, Ilja van - \ 2020
Frontiers in Earth Science 8 (2020). - ISSN 2296-6463
citizen science - floating debris - hydrology - Klang - marine litter - plastic - Rhine - riverbank plastic
Macroplastic pollution (> 0.5 cm) negatively impacts aquatic life and threatens human livelihood on land, in oceans and river systems. Reliable information on the origin, fate and pathways of plastic in river systems is required to optimize prevention, mitigation and reduction strategies. Yet, accurate and long-term data on plastic transport are still lacking. Current macroplastic monitoring strategies involve labor intensive sampling methods, require investment in infrastructure, and are therefore infrequent. Crowd-based observations of riverine macroplastic pollution may potentially provide frequent cost-effective data collection over a large geographical range. We extended the CrowdWater citizen science app for hydrological observations with a module for observations of plastic in rivers. In this paper, we demonstrate the potential of crowd-based observations of floating macroplastic and macroplastic on riverbanks. We analyzed data from two case studies: (1) floating plastic measured in the Klang (Malaysia), and (2) plastic on riverbanks along the Rhine (the Netherlands). Crowd-based observations of floating plastic in the Klang yield similar estimates of plastic transport (2,000–3,000 items h−1), cross-sectional distribution (3–7 percent point difference) and polymer categories (0–6 percent point difference) as reference observations. It also highlighted the high temporal variation in riverine plastic transport. The riverbank observations provided the first data of macroplastic pollution on the most downstream stretch of the Rhine, revealing peaks close to urban areas and an increasing plastic density toward the river mouth. The mean riverbank density estimates are also similar for the crowd-based and reference methods (573–1,033 items km−1). These results highlight the value of including crowd-based riverine macroplastic observations in future monitoring strategies. Crowd-based observations may provide reliable estimations of plastic transport, density, spatiotemporal variation and composition for a larger number of locations than conventional methods.
Shellfish as pre-filtration of marine intake water in a reverse electro dialysis energyplant : Effect of shellfish filtration during two experiments: Spring and Summer 2019 (Deliverables D3.2 and D3.3)
Walles, B. ; Dalen, P. van; Walraven, L. van; Grasman, S. ; Wijsman, J.W.M. - \ 2020
Yerseke : Wageningen Marine Research (Wageningen Marine Research report C082/20) - 31
In a reverse electro dialysis (RED) installation, power is produced from the chemical potential difference between salt- and freshwater using ion-selective membranes. In order to make a RED plant commercially feasible, large amounts of salt- and freshwater are needed. At the Afsluitdijk, salt water can be extracted from the Wadden Sea and freshwater from Lake IJssel. The water from the Wadden Sea, however, contains high concentrations of suspended particles (on average ca 50 mg l-1). These particles adversely affect the efficiency of the plant and need to be removed from the water before it enters the membrane stacks. Shellfish are efficient filterfeeders that are capable to filter large amounts of suspended solids from the water. Therefore, it has been suggested that shellfish can be used to pre-filter the water from the Wadden Sea, before it enters the reverse electro dialysis power plant. In a previous model study, it has been shown that, depending on residence times and amount of shellfish, mussels are capable to remove 50% of the suspended particles from the water. In this report, the results of a large-scale experimental study, that was executed to test if shellfish can be used as pre-filter for marine intake water, are presented. Two consecutive experiments (in spring and in summer) were run at the test facility at the Afsluitdijk using the blue mussel (Mytilus edulis). Filtration efficiency of marine intake water by shellfish was measured in a flow-through system containing mussels and compared to a control flow-through system without shellfish. The flow-through system was designed to create low flow velocities allowing the larger suspended particles (faeces and pseudofaeces) to sink and accumulate at the cone-shaped bottom of the tank. The accumulated deposits can be quantified and removed from the tank. The results of the large-scale experiments showed that depending on the set-up, the mussels were able to remove 6-11% of the incoming sediment over a period of 2 to 3 months. Within this period, moments occurred where more than 50% of the suspended particles were removed by the mussels. During the experiment in spring, the deposition rate in the tank with mussels (average 95 kg fresh weight) was on average 2.9 kg day-1 while the deposition rate in the control tank, without mussels, was 1.2 kg day-1. During the experiment in summer, the deposition rates in the mussel (average 35 kg fresh weight) and control tanks were 2.4 and 0.4 kg day-1, respectively. At a flow rate of 5 m3 per hour 11% of the incoming suspended matter was filtered by on average 35 kg of mussels. A powerplant with a capacity of 10 MW needs 10 m3 s-1 sea water (36 000 m3 per hour). To pre-filter the water with an efficiency of 11%, a total of 252 000 kg of mussels are needed, producing a total of about 16 tons of biodeposits per day. For upscaling purposes the design of the shellfish filtration system should be optimised to increase filtration efficiency of the mussels, minimize resuspension of (pseudo)faeces and increase the efficiency to remove the produced (pseudo)faeces from the systems. During the experiments, the mussels survived and even increased in weight. In the spring experiment the mussels grew on average 5 mm in length, increased their fresh weight (shell + tissue) by 62% and increased their flesh percentage on average from 12.7% to 20.6% over the course of the experiment executed between March and May. Approximately 57% of the mussels survived the experiment. Over the course of the experiment executed in summer (June – September), mussels grew on average 3 mm in length and increased their fresh weight (shell + tissue) by 15%. Percentage flesh decreased from 12.7% to 8.0% over the course of the experiment. The survival of the mussels during the second experiment was lower (38%) than in the first experiment. It is expected that modifications in the design of the set-up will increase the efficiency of the sediment removal from the water and the survival of the mussels.
Effects of drop height, conveyor belt speed, and acceleration on the welfare of broiler chickens in early and later life
Giersberg, Mona F. ; Molenaar, Roos ; Pieters, Remco ; Boyer, William ; Rodenburg, T.B. - \ 2020
Poultry Science (2020). - ISSN 0032-5791
During automated processing in commercial hatcheries, day-old chicks are subjected to a range of possible mental and physical stressors. Three determinants of the processing line seem to have the potential to affect the birds in particular: drop height from one conveyor belt to another, conveyor belt speed, and acceleration. The aim of this study was to evaluate the effects of these 3 factors on chicken health and welfare in early and later life. In a first trial, chickens were tested on an experimental processing line that was adjusted to different levels of drop heights, belt speeds, and accelerations separately (n = 14 animals per factor and increment). Besides the assessment of several indicators for disorientation during the treatment, postmortem radiographic images were created and analyzed with focus on traumatic injuries. The number of chickens changing their orientation after the drop was affected by drop height (P < 0.01), whereas body posture changes were affected both by drop height (P < 0.01) and belt speed (P < 0.01). Traumatic injuries were found only sporadically and were not related to a certain treatment. In a second trial, chickens that were exposed to a combination of the 3 processing factors were compared with an untreated control group (n = 63 per group) until 15 d of age. There were no differences between the 2 groups regarding BW, welfare scores, and fear-related responses in a novel object and in a tonic immobility test. The present results suggest that the treatments on the experimental conveyor belts affected the birds' health, welfare, and behavior to a limited extend. However, starting at a drop height of 280 mm and a conveyor belt speed of 27 m/min, significantly more chickens were not able to maintain their initial body position on the belt. This indicates that there may be scope for discomfort and welfare impairment if commercial systems are operated with considerably larger drop heights and at higher speeds.
Terrestrial laser scanning in forest ecology : Expanding the horizon
Calders, Kim ; Adams, Jennifer ; Armston, John ; Bartholomeus, Harm ; Bauwens, Sebastien ; Bentley, Lisa Patrick ; Chave, Jerome ; Danson, Mark ; Demol, Miro ; Disney, Mathias ; Gaulton, Rachel ; Krishna Moorthy, Sruthi M. ; Levick, Shaun R. ; Saarinen, Ninni ; Schaaf, Crystal ; Stovall, Atticus ; Terryn, Louise ; Wilkes, Phil ; Verbeeck, Hans - \ 2020
Remote Sensing of Environment 251 (2020). - ISSN 0034-4257
Forest ecology - Forest plot measurement - Ground-based LiDAR - Remote sensing - Terrestrial laser scanning - Tree structure
Terrestrial laser scanning (TLS) was introduced for basic forest measurements, such as tree height and diameter, in the early 2000s. Recent advances in sensor and algorithm development have allowed us to assess in situ 3D forest structure explicitly and revolutionised the way we monitor and quantify ecosystem structure and function. Here, we provide an interdisciplinary focus to explore current developments in TLS to measure and monitor forest structure. We argue that TLS data will play a critical role in understanding fundamental ecological questions about tree size and shape, allometric scaling, metabolic function and plasticity of form. Furthermore, these new developments enable new applications such as radiative transfer modelling with realistic virtual forests, monitoring of urban forests and larger scale ecosystem monitoring through long-range scanning. Finally, we discuss upscaling of TLS data through data fusion with unmanned aerial vehicles, airborne and spaceborne data, as well as the essential role of TLS in validation of spaceborne missions that monitor ecosystem structure.
Simulating the effects of water limitation on plant biomass using a 3D functional-structural plant model of shoot and root driven by soil hydraulics
Braghiere, Renato K. ; Gérard, Frédéric ; Evers, Jochem B. ; Pradal, Christophe ; Pagès, Loïc - \ 2020
Annals of Botany 126 (2020)4. - ISSN 0305-7364 - p. 713 - 728.
ArchiSimple - functional-structural plant models - GroIMP - intercropping - Min3P - photosynthesis - soil modelling - soil-plant interactions - water deficit - water uptake
BACKGROUND AND AIMS: Improved modelling of carbon assimilation and plant growth to low soil moisture requires evaluation of underlying mechanisms in the soil, roots, and shoots. The feedback between plants and their local environment throughout the whole spectrum soil-root-shoot-environment is crucial to accurately describe and evaluate the impact of environmental changes on plant development. This study presents a 3D functional structural plant model, in which shoot and root growth are driven by radiative transfer, photosynthesis, and soil hydrodynamics through different parameterisation schemes relating soil water deficit and carbon assimilation. The new coupled model is used to evaluate the impact of soil moisture availability on plant productivity for two different groups of flowering plants under different spatial configurations. METHODS: In order to address different aspects of plant development due to limited soil water availability, a 3D FSP model including root, shoot, and soil was constructed by linking three different well-stablished models of airborne plant, root architecture, and reactive transport in the soil. Different parameterisation schemes were used in order to integrate photosynthetic rate with root water uptake within the coupled model. The behaviour of the model was assessed on how the growth of two different types of plants, i.e. monocot and dicot, is impacted by soil water deficit under different competitive conditions: isolated (no competition), intra, and interspecific competition. KEY RESULTS: The model proved to be capable of simulating carbon assimilation and plant development under different growing settings including isolated monocots and dicots, intra, and interspecific competition. The model predicted that (1) soil water availability has a larger impact on photosynthesis than on carbon allocation; (2) soil water deficit has an impact on root and shoot biomass production by up to 90 % for monocots and 50 % for dicots; and (3) the improved dicot biomass production in interspecific competition was highly related to root depth and plant transpiration. CONCLUSIONS: An integrated model of 3D shoot architecture and biomass development with a 3D root system representation, including light limitation and water uptake considering soil hydraulics, was presented. Plant-plant competition and regulation on stomatal conductance to drought were able to be predicted by the model. In the cases evaluated here, water limitation impacted plant growth almost 10 times more than the light environment.
Understanding the Coula edulis, Dacryodes buettneri and Irvingia gabonensis non-timber forest product value chains from Makokou, North-East Gabon from a gender perspective
Yobo, C.M. ; Awono, A. ; Ingram, V.J. - \ 2020
International Forestry Review 22 (2020)3. - ISSN 1465-5489 - p. 339 - 354.
Trade-in Non-Timber Forest Products (NTFPs) in the Congo Basin is a source of cash income for stakeholders in their value chains, from
harvesters to traders. However, gender-disaggregated data on the benefits of such trade in Gabon remains poorly captured and used by policymakers,
despite a decree on women’s empowerment enacted by the Republic of Gabon in 2017. This study assesses gender dynamics, reasons
for entering the trade, economics, and perceived threats to Coula edulis, Dacryodes buettneri, and Irvingia gabonensis value chains originating
in Makokou, Gabon. Data from field observations, key informants, and 79 semi-structured interviews with stakeholders in three markets showed that activities in the value chains of these three NTFPs were highly gender-differentiated. Women dominate in all three chains, particularly in the two lower-value products. This was driven by women’s vulnerability and men’s preference for higher-value timber and NTFPs. Both men and women enter the trade mostly because they lack other ways to generate income and employment. The men involved in the chains tended to harvest slightly larger volumes and sell at higher prices. The NTFPs and their value chains were all perceived as threatened by climate change, deforestation, and unsustainable forest resources management, with both men and women aware of these threats. The importance of the NTFP trade for women suggested that policies and gender focus interventions, for example on domestication, cultivation, value-adding to improve and sustain their income, could contribute to more sustainable value chains and livelihoods
Molecular Signatures of Placentation and Secretion Uncovered in Poeciliopsis Maternal Follicles
Guernsey, Michael W. ; Kruistum, Henri van; Reznick, David N. ; Pollux, Bart J.A. ; Baker, Julie C. - \ 2020
Molecular Biology and Evolution 37 (2020)9. - ISSN 0737-4038 - p. 2679 - 2690.
placenta - Poeciliopsis - transcriptome
Placentation evolved many times independently in vertebrates. Although the core functions of all placentas are similar, we know less about how this similarity extends to the molecular level. Here, we study Poeciliopsis, a unique genus of live-bearing fish that have independently evolved complex placental structures at least three times. The maternal follicle is a key component of these structures. It envelops yolk-rich eggs and is morphologically simple in lecithotrophic species but has elaborate villous structures in matrotrophic species. Through sequencing, the follicle transcriptome of a matrotrophic, Poeciliopsis retropinna, and lecithotrophic, P. turrubarensis, species we found genes known to be critical for placenta function expressed in both species despite their difference in complexity. Additionally, when we compare the transcriptome of different river populations of P. retropinna, known to vary in maternal provisioning, we find differential expression of secretory genes expressed specifically in the top layer of villi cells in the maternal follicle. This provides some of the first evidence that the placental structures of Poeciliopsis function using a secretory mechanism rather than direct contact with maternal circulation. Finally, when we look at the expression of placenta proteins at the maternal-fetal interface of a larger sampling of Poeciliopsis species, we find expression of key maternal and fetal placenta proteins in their cognate tissue types of all species, but follicle expression of prolactin is restricted to only matrotrophic species. Taken together, we suggest that all Poeciliopsis follicles are poised for placenta function but require expression of key genes to form secretory villi.
Differently Pre-treated Rapeseed Meals Affect in vitro Swine Gut Microbiota Composition
Long, Cheng ; Vries, Sonja de; Venema, Koen - \ 2020
Frontiers in Microbiology 11 (2020). - ISSN 1664-302X
adaptation period - alkaline - cellulase - pectinase - pig gut microbiota - rapeseed meal
The aim of the study was to investigate the effect of untreated and processed rapeseed meal (RSM) on fiber degradability by pig gut microbiota and the adaptation of the microbiota to the substrate, by using the Swine Large Intestine in vitro Model (SLIM). A standardized swine gut microbiota was fed for 48 h with pre-digested RSM which was processed enzymatically by a cellulase (CELL), two pectinases (PECT), or chemically by an alkaline (ALK) treatment. Amplicons of the V3–V4 region of the 16S rRNA gene were sequenced to evaluate the gut microbiota composition, whereas short chain fatty acids (SCFA) were measured to assess fiber degradation. Adaptive gPCA showed that CELL and ALK had larger effects on the microbiota composition than PECT1 and PECT2, and all substrates had larger effects than CON. The relative abundance of family Prevotellaceae was significantly higher in CELL treatment compared to other treatments. Regardless of the treatments (including CON), the relative abundance of Dorea, Allisonella, and FamilyXIIIUCG_001 (in the order of Clostridiales) were significantly increased after 24 h, and Parabacteroides, Mogibacterium, Intestinimonas, Oscillibacter, RuminococcaceaeUCG_009, Acidaminococcus, Sutterella, and Citrobacter were significantly higher in abundance at time point 48 compared to the earlier time points. Prevotella 9 had significant positive correlations with propionic and valeric acid, and Mogibacterium positively correlated with acetic and caproic acid. There was no significant difference in SCFA production between untreated and processed RSM. Overall, degradability in the processed RSM was not improved compared to CON. However, the significantly different microbes detected among treatments, and the bacteria considerably correlating with SCFA production might be important findings to determine strategies to shorten the fiber adaptation period of the microbiota, in order to increase feed efficiency in the animal, and particularly in pig production.
Does forestland possession enhance households’ access to credit?—Examining China's forestland mortgage policy
Dong, Jiayun ; Liang, Wenyuan ; Liu, Weiping ; Liu, Jinlong ; Managi, Shunsuke - \ 2020
Economic Analysis and Policy 68 (2020). - ISSN 0313-5926 - p. 78 - 87.
China's forest tenure reform - Forestland possession - Loan - Mortgage
Many countries have seen a rising demand for forest policy reform. This paper explores the effects of China's forestland mortgage policy, a supporting measure for collective forest tenure reform, on household credit access. In theory, the forestland mortgage policy could have three impacts on households: (1) forestland possession could change households’ willingness to access credit (2) forestland possession could enhance household access to credit, and (3) the contract structure follows the theoretical predictions of the credit contract design mechanism. Our results show that households’ willingness to enroll in the mortgage policy as well as their potential to obtain credit increased when households possessed larger areas of forestland. However, the proportion of households that successfully obtained credit were fairly modest. Meanwhile, we found a positive relationship between collateralized forestland and the amount of the forestland mortgage loan, and a negative relationship between collateralized forestland and the interest rate. These findings are consistent with the theoretical predictions of the contract mechanism design. The existing forestland mortgage policy has increased households’ credit access to some extent; however, there is much room for improvement from a policy perspective. This requires divising policy arrangements that would facilitate a fully developed credit market available to households. Forest tenure mortgage loans alone may not be able to fully meet households’ financial needs.
Genetic variation in the feeding behavior of isofemale lines of nesidiocoris tenuis
Chinchilla-Ramírez, Milena ; Pérez-Hedo, Meritxell ; Pannebakker, Bart A. ; Urbaneja, Alberto - \ 2020
Insects 11 (2020)8. - ISSN 2075-4450 - p. 1 - 13.
Biological control - Miridae - Phytophagy - Tomato - Zoophagy - Zoophytophagous predator
Zoophytophagous predators provide biocontrol services in various major crops of modern horticulture due to the combination of its predatory capacity and the induction of plant defenses derived from its phytophagy. However, under certain conditions of prey scarcity, these natural enemies can inflict plant damage. Exploitation of genetic variation and subsequent selective breeding on foraging traits is a potential alternative to overcome this inconvenience. In this study, we quantified the genetic variation of phytophagy and zoophagy of Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae), a zoophytophagous predator widely used in tomato crops to suppress key pests. We compared nine isofemale lines on their capacity to produce necrotic rings and wilting on tomato plants as a proxy for phytophagy, as well as their efficacy to prey on Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs, as a proxy for zoophagy. Differences between isofemale lines in phytophagy and zoophagy indicated a genetic basis. Variation found in the zoophagy levels was larger than that in phytophagy levels. Our results showed that there is a genetic basis for the variation observed in the feeding behavior of isofemale lines of N. tenuis, highlighting the potential importance of selective breeding for such traits of biocontrol interest.
Development and thermal activity thresholds of European mirid predatory bugs
Ingegno, Barbara L. ; Messelink, Gerben J. ; Leman, Ada ; Sacco, Dario ; Tavella, Luciana - \ 2020
Biological Control 152 (2020). - ISSN 1049-9644
Biological control agents - D. eckerleini - D. errans - D. flavoviridis - Dicyphus bolivari - Macrolophus pygmaeus - Nesidiocoris tenuis - Temperature regimes
Generalist predators belonging to Dicyphini (Hemiptera: Miridae) play an important role in pest control in vegetable crops. Temperature is one the most important factors affecting their efficacy as biological control agents (BCAs) and a better understanding of temperature effects can help to select the best performing species for certain climatic conditions. In this study we assessed the thermal requirements of six dicyphine species: Dicyphus bolivari (2 different strains), Dicyphus eckerleini, Dicyphus errans, Dicyphus flavoviridis, Nesidiocoris tenuis and Macrolophus pygmaeus. Two experimental methods were used: one static, by recording the developmental times at six temperatures (15–40 °C) and one dynamic, by determining low and high temperature thresholds for movement. Based on the results of both methods we identified two groups: N. tenuis, M. pygmaeus and D. bolivari showed the best performance at high temperatures and the species D. errans, D. eckerleini and D. flavoviridis were most active at low temperatures. Dicyphus bolivari and N. tenuis were the only species able to reach adulthood at the constant temperature of 35 °C. At low temperatures, D. eckerleini and D. errans were the only species still able to walk below 0 °C. The species less vulnerable for lower temperatures were more vulnerable for higher temperatures and vice-versa. Among the tested species, the larger sized species seem to be better adapted to lower temperature and the and smaller sized species better to higher temperatures. Females and males in all species differed in their cold and heat tolerance. Males were in general beter adapted to higher temperatures and females beter adapted to lower temperatures.
Modeling soil and landscape evolution - The effect of rainfall and land-use change on soil and landscape patterns
Meij, W.M. Van Der; Temme, Arnaud J.A.M. ; Wallinga, Jakob ; Sommer, Michael - \ 2020
SOIL 6 (2020)2. - ISSN 2199-3971 - p. 337 - 358.
Humans have substantially altered soil and landscape patterns and properties due to agricultural use, with severe Impacts on biodiversity, carbon sequestration and food security. These Impacts are difficult to quantify, because we lack data on long-term changes In soils In natural and agricultural settings and available simulation methods are not suitable for reliably predicting future development of soils under projected changes In climate and land management. To help overcome these challenges, we developed the HydroLorica soil-landscape evolution model that simulates soil development by explicitly modeling the spatial water balance as a driver of soil- and landscape-forming processes. We simulated 14 500 years of soil formation under natural conditions for three scenarios of different rainfall Inputs. For each scenario we added a 500-year period of Intensive agricultural land use, where we Introduced tillage erosion and changed vegetation type.
Our results show substantial differences between natural soil patterns under different rainfall Input. With higher rainfall, soil patterns become more heterogeneous due to Increased tree throw and water erosion. Agricultural patterns differ substantially from the natural patterns, with higher variation of soil properties over larger distances and larger correlations with terrain position. In the natural system, rainfall Is the dominant factor Influencing soil variation, while for agricultural soil patterns landform explains most of the variation simulated. The cultivation of soils thus changed the dominant factors and processes Influencing soil formation and thereby also Increased predictability of soil patterns. Our study highlights the potential of soil-landscape evolution modeling for simulating past and future developments of soil and landscape patterns. Our results confirm that humans have become the dominant soil-forming factor In agricultural landscapes.
Automated River Plastic Monitoring Using Deep Learning and Cameras
Lieshout, Colin van; Oeveren, Kees van; Emmerik, Tim van; Postma, Eric - \ 2020
Earth and Space Science 7 (2020)8. - ISSN 2333-5084
artificial intelligence - automated monitoring - deep learning - object detection - plastic pollution - river plastic
Quantifying plastic pollution on surface water is essential to understand and mitigate the impact of plastic pollution to the environment. Current monitoring methods such as visual counting are labor intensive. This limits the feasibility of scaling to long-term monitoring at multiple locations. We present an automated method for monitoring plastic pollution that overcomes this limitation. Floating macroplastics are detected from images of the water surface using deep learning. We perform an experimental evaluation of our method using images from bridge-mounted cameras at five different river locations across Jakarta, Indonesia. The four main results of the experimental evaluation are as follows. First, we realize a method that obtains a reliable estimate of plastic density (68.7% precision). Our monitoring method successfully distinguishes plastics from environmental elements, such as water surface reflection and organic waste. Second, when trained on one location, the method generalizes well to new locations with relatively similar conditions without retraining (≈50% average precision). Third, generalization to new locations with considerably different conditions can be boosted by retraining on only 50 objects of the new location (improving precision from ≈20% to ≈42%). Fourth, our method matches visual counting methods and detects ≈35% more plastics, even more so during periods of plastic transport rates of above 10 items per meter per minute. Taken together, these results demonstrate that our method is a promising way of monitoring plastic pollution. By extending the variety of the data set the monitoring method can be readily applied at a larger scale.
High-intensity ultrasound treatment on soy protein after selectively proteolyzing glycinin component: Physical, structural, and aggregation properties
Xia, Wenjie ; Pan, Siyi ; Cheng, Zhe ; Tian, Yan ; Huang, Xingjian - \ 2020
Foods 9 (2020)6. - ISSN 2304-8158
Gelation - High-intensity ultrasound - Pepsin - Selective proteolysis - Soluble aggregates
In this study, a novel method called selective proteolysis was applied to the glycinin component of soy protein isolate (SPI), and a degraded glycinin hydrolysate (DGH) was obtained. The effects of high-intensity ultrasound (HIU) treatment (20 kHz at 400 W, 0, 5, 20, and 40 min) on the physical, structural, and aggregation properties of DGH were investigated with the aim to reveal the influence of the selectively hydrolyzing glycinin component on the HIU treatment of soy protein. The effects of HIU on DGH and a control SPI (CSPI) were both time-dependent. HIU induced the formation of soluble aggregates in both samples at an early stage, while it dissociated these newly formed aggregates after a longer duration. Selectively hydrolyzing glycinin contributed to the soluble aggregation by exposing the compact protein structure and producing small protein fractions. The larger extent of hydrophobic interactions and disulfide bonds imparted a higher stability to the soluble protein aggregates formed in DGH. As a result, DGH displayed more ordered secondary structures, a higher solubility, and better gelling properties after the HIU treatment, especially at 20 min. The results of this study will be beneficial to the scientific community as well as industrial application.
Mesoscale model simulation of a severe summer Thunderstorm in The Netherlands: Performance and uncertainty assessment for parameterised and resolved convection
Steeneveld, Gert Jan ; Peerlings, Esther E.M. - \ 2020
Atmosphere 11 (2020)8. - ISSN 2073-4433
Cumulus parameterisation - Grey zone - Mesoscale convective system - The Netherlands - WRF model
On the evening of 23 June 2016 around 18:00 UTC, a mesoscale convective system (MCS) with hail and wind gusts passed the southern province Noord-Brabant in the Netherlands, and caused 675 millions of euros damage. This study evaluates the performance of the Weather Research and Forecasting model with three cumulus parameterisation schemes (Betts-Miller-Janjic, Grell-Freitas and Kain-Fritsch) on a grid spacing of 4 km in the 'grey-zone' and with explicitly resolved convection at 2 and 4 km grid spacing. The results of the five experiments are evaluated against observations of accumulated rainfall, maximum radar reflectivity, the CAPE evolution and wind speed. The results show that the Betts-Miller-Janjic scheme is activated too early and can therefore not predict any MCS over the region of interest. The Grell-Freitas and Kain-Fritsch schemes do predict an MCS, but its intensity is underestimated. With the explicit convection, the model is able to resolve the storm, though with a delay and an overestimated intensity. We also study whether spatial uncertainty in soil moisture is scaled up differently using parameterised or explicitly resolved convection. We find that the uncertainty in soil moisture distribution results in larger uncertainty in convective activity in the runs with explicit convection and the Grell-Freitas scheme, while the Kain-Fritsch and Betts-Miller-Janjic scheme clearly present a smaller variability.
Population- and Species-Based Variation of Webworm-Parasitoid Interactions in Hogweeds (Heracelum spp.) in the Netherlands
Harvey, Jeffrey A. ; Ode, Paul J. ; Gols, Rieta - \ 2020
Environmental Entomology 49 (2020)4. - ISSN 0046-225X - p. 924 - 930.
Copidosoma sosares - Depressaria radiella - co-evolution - fitness - parsnip webworm
In three Dutch populations of the native small hogweed (Heracleum sphondylium L. [Apiales: Apiaceae]), and one of the invasive giant hogweed (H. mantegazzianum Sommeier & Levier [Apiales: Apiaceae]), interactions between a specialist herbivore, the parsnip webworm (Depressaria radiella), and its associated parasitoids were compared during a single growing season. We found host plant species-related differences in the abundance of moth pupae, the specialist polyembryonic endoparasitoid, Copidosoma sosares, the specialist pupal parasitoid, Barichneumon heracliana, and a potential hyperparasitoid of C. sosares, Tyndaricus scaurus Walker (Hymenoptera: Encyrtidae). Adult D. radiella body mass was similar across the three small hogweed populations, but moths and their pupal parasitoid B. heracliana were smaller when developing on giant than on small hogweeds where the two plants grew in the same locality (Heteren). Mixed-sex and all-male broods of C. sosares were generally bigger than all-female broods. Furthermore, adult female C. sosares were larger than males and adult female mass differed among the three small hogweed populations. The frequency of pupal parasitism and hyperparasitism also varied in the different H. sphondylium populations. These results show that short-term (intra-seasonal) effects of plant population on multitrophic insects are variable among different species in a tightly linked food chain.