scholarly journals Inter-annual weather variability can drive the outcome of predator prey match in ponds

2015 ◽  
Vol 36 (2) ◽  
pp. 97-109 ◽  
Author(s):  
Timm Reinhardt ◽  
Sebastian Steinfartz ◽  
Markus Weitere
Keyword(s):  
Prey Availability ◽  
Weather Conditions ◽  
Single Species ◽  
Growth Conditions ◽  
Initial Growth ◽  
Ephemeral Ponds ◽  
Complete Life Cycle ◽  
Compensation Mechanisms ◽  
In The Beginning ◽  
Salamander Larvae

The matching of life-history-events to the availability of prey is essential for the growth and development of predators. Mismatches can constrain individuals to complete life-cycle steps in time and in ephemeral habitats it can lead to mortality unless compensation mechanisms exist. Here we measured the performance of a population of European fire-salamanders (Salamandra salamandra) and their prey in ephemeral ponds. We analysed how short time inter-annual variability of yearly rainfall and temperature (two consecutive years, 2011 and 2012) affects matching of predator and prey and how two different weather scenarios influenced the predator’s population structure. A single species (larvae of the mosquito Aedes vexans) dominates the prey community here, which occurs in high quantities only in the beginning of the season. When the occurrence of prey and predator matched during a period of sufficiently high temperatures (as in 2011), initial growth of the salamander larvae was high and population size development homogeneous. At low temperatures during matching of predatory and prey (as in 2012), the initial growth was low but the salamander larvae developed into two distinctly different sizes. Further, some individuals in the large cohort became cannibalistic and initial size differences increased. As a result, the latest (smallest) cohort disappeared completely. Temperature measurements and estimation of maximal growth rates revealed that temperature differences alone could explain the different early development between years. Our data show that weather conditions (rainfall; temperature during early growth phase) strongly determined the performance of salamander larvae in ponds. Our data also add to the match-mismatch concept that abiotic growth conditions (here: low temperature) could prevent efficient conversion of prey- into predator-biomass despite high prey availability.

Potential displacement of the native Tenuisvalvae notata by the invasive Cryptolaemus montrouzieri in South America suggested by differences in climate suitability

2021 ◽  
pp. 1-11
Author(s):  
Larissa F. Ferreira ◽  
Christian S. A. Silva-Torres ◽  
Jorge B. Torres ◽  
Robert C. Venette
Keyword(s):  
Biological Control ◽  
South America ◽  
Prey Availability ◽  
Ecological Factors ◽  
Growth Conditions ◽  
Cryptolaemus Montrouzieri ◽  
Seasonal Differences ◽  
Ladybird Beetle ◽  
Ecoclimatic Index ◽  
Climate Suitability

Abstract Tenuisvalvae notata (Mulsant) (Coccinellidae) is a predatory ladybird beetle native to South America. It specializes in mealybugs prey (Pseudococcidae), but relatively little is known about its ecology. In contrast, the ladybird beetle Cryptolaemus montrouzieri Mulsant (Coccinellidae) is indigenous to Australia and has been introduced to many countries worldwide including Brazil for biological control of mealybugs. The potential impacts of these introductions to native coccinellids have rarely been considered. The software CLIMEX estimated the climate suitability for both species as reflected in the Ecoclimatic Index (EI). Much of South America, Africa, and Australia can be considered climatically suitable for both species, but in most cases, the climate is considerably more favorable for C. montrouzieri than T. notata, especially in South America. The CLIMEX model also suggests seasonal differences in growth conditions (e.g. rainfall and temperature) that could affect the phenology of both species. These models suggest that few locations in South America would be expected to provide T. notata climatic refugia from C. montrouzieri. Although other ecological factors will also be important, such as prey availability, this analysis suggests a strong potential for displacement of a native coccinellid throughout most of its range as a consequence of the invasion by an alien competitor.

Mn5Ge3 ultra-thin films on GaAs (111)B substrates: Influence of initial growth conditions

2020 ◽  
Vol 148 ◽  
pp. 106745
Author(s):  
S.J. Gutiérrez-Ojeda ◽  
R.C. de Oliveira ◽  
H.N. Fernández-Escamilla ◽  
R. Ponce-Pérez ◽  
J. Guerrero-Sánchez ◽  
...  
Keyword(s):  
Thin Films ◽  
Growth Conditions ◽  
Initial Growth

scholarly journals Crescimento inicial da berinjeleira sob adubação nitrogenada e fosfatada e irrigada com água de reúso

2015 ◽  
Vol 10 (3) ◽  
pp. 34 ◽  
Author(s):  
Aldair de Souza Medeiros ◽  
Reginaldo Gomes Nobre ◽  
Eliane da Silva Ferreira ◽  
Whalamys Lourenço de Araújo ◽  
Manoel Moises Ferreira de Queiroz
Keyword(s):  
Reclaimed Water ◽  
Weather Conditions ◽  
Dry Mass ◽  
Industrial Sector ◽  
Treated Wastewater ◽  
Intermittent Flow ◽  
Phosphorus Fertilization ◽  
Initial Growth ◽  
Nitrogen And Phosphorus ◽  
Sand Filter

<p><span>A utilização da água vem gerando alguns conflitos devido o aumento da escassez hídrica em todo o mundo, os setores de maior consumo são a agricultura responde por 70%, o setor industrial 22% e 8% corresponde ao uso doméstico. Objetivou-se com este trabalho avaliar os efeitos causados pelas doses de nitrogênio e fósforo e a irrigação com água de reúso doméstica pós-tratada em filtro de areia com fluxo intermitente durante o crescimento inicial da berinjeleira na região semiárida paraibana. O experimento foi realizado em ambiente protegido, no Centro de Ciências e Tecnologia Agroalimentar (CCTA/UFCG), Campus de Pombal – PB, e cujos tratamentos resultaram na combinação de dois fatores: quatro doses de adubação nitrogenada (N<sub>1 </sub>- 3,55; N<sub>2</sub> - 6,2; N<sub>3</sub> - 8,9; N<sub>4</sub> - 11,55 g de N/vaso) e quatro doses de adubação fosfatada (P<sub>1</sub> - 15,28; P<sub>2</sub> - 26,74; P<sub>3</sub> - 38,2; P<sub>4</sub> - 49,66 g de P/vaso) correspondendo respectivamente a 40; 70; 100; 130% conforme indicação de adubação para a cultura da berinjela quando cultivada em vasos, irrigada com água de reúso pós-tratada em filtro de areia intermitente (AR). O delineamento experimental adotado foi o de blocos inteiramente casualizados, com os tratamentos arranjados em esquema fatorial 4 x 4, com quatro repetições. Conclui-se que a prática da irrigação com água de reúso surge como uma fonte hídrica e nutricional para a cultura da berinjela, nas condições edafoclimáticas do semiárido; Doses de 3,55 g de N e 15,28 g de P por planta quando se utiliza água de reúso na irrigação de plantas de berinjela são suficientes para suprir as necessidades nutricionais da cultura. A massa fresca da folha de plantas de berinjela decresceu linearmente com o incremento das doses de N aplicadas. A produção de massa fresca e seca da parte aérea de plantas de berinjela irrigadas com água de reúso com 40% da adubação com N e P não diferiu das plantas que receberam 100% indicação de N e P.</span></p><p align="center"><strong><em>Eggplant early growth under nitrogen and phosphate and irrigated with reuse water</em></strong></p><p><strong>ABSTRACT - </strong>The use of water has generated some conflicts due to increasing water scarcity around the world, the largest consumer sectors are agriculture accounts for 70 %, the industrial sector 22% and 8% corresponds to the household. The objective of this study was to evaluate the effects caused by nitrogen and phosphorus and irrigation with reclaimed water post- treated domestic sand filter with intermittent flow during the initial growth of eggplant in Paraíba semi-arid region.The experiment was conducted in a greenhouse, in the Science and Technology Center Agrifood (CCTA / UFCG), Campus de Pombal - PB, and the treatments resulted in the combination of two factors: four doses of nitrogen (N1 - 3.55; N2 - 6.2; N3 - 8.9; N4 - 11.55 g N / pot) and four doses of phosphorus fertilization (P1 - 15.28; P2 - 26.74; P3 - 38.2; P4 - 49 66 g P / pot) corresponding respectively to 40; 70; 100; 130% as fertilizer indication for eggplants when grown in pots irrigated with treated wastewater post-intermittent sand filter (AR). The experimental design was a completely randomized design, with treatments arranged in a factorial 4 x 4, with four replications. We conclude it the practice of irrigation with reclaimed water emerges as a water and nutrient source for the eggplant crop, soil and weather conditions in the semiarid; Doses of 3,55 g of N and 15,28 g P per plant when using reclaimed water in irrigation eggplants are sufficient to meet the nutritional needs of the crop. The fresh weight of eggplants sheet decreased linearly with increasing N rates. The production shoot fresh and dry mass of eggplant plants irrigated with reclaimed water to 40% of fertilization with N and P did not differ from plants that received 100 % of N and P indication.</p><p><span><br /></span></p>

scholarly journals Strip-till technology - a method for uniformity in the emergence and plant growth of winter rapeseed (Brassica napus L.) in different environmental conditions of Northern Poland

2018 ◽  
pp. 194-199 ◽  
Author(s):  
Iwona Jaskulska ◽  
Lech Gałęzewski ◽  
Mariusz Piekarczyk ◽  
Dariusz Jaskulski
Keyword(s):  
Plant Growth ◽  
Environmental Conditions ◽  
Block Design ◽  
Thermal Conditions ◽  
Weather Conditions ◽  
Field Trials ◽  
Initial Growth ◽  
Brassica Napus L ◽  
Initial Development ◽  
Winter Rapeseed

The emergence of plants is especially important for the winter crops that are grown in the challenging environmental conditions of many countries in Central and Eastern Europe. The emergence and initial growth of winter rapeseed were compared in field trials in a randomized block design with three replicates for plants sown in conventional tillage systems (CT) and strip-till (ST), which had different weather conditions and on soil with a non-uniform texture over a period of two years. Sowing in the CT was carried out using Horsch Pronto 4DC (Germany) at a row distance of 0.29 m. The ST operations were performed using a Pro-Til 4T drill manufactured by Mzuri Limited (Great Britain) - row spacing of 0.36 m. In favourable rainfall and thermal conditions, the density of winter rapeseed plants two weeks after sowing was found to be higher if it was sown after the CT than in the ST system. In the year that had a serious shortage of rainfall during the sowing period, a considerably higher density of plants was achieved using the ST system. The uniformity of plant growth using the ST technology in soil with a varied texture, especially in a year with an unfavourable distribution of rainfall, was proven by less variability in the number of leaves in the rosette, in the dry mass of the leaf rosette and in the root neck thickness of the winter rapeseed than in the CT system. The ST system can create good conditions for the initial development and preparation of rapeseed plants for wintering.

scholarly journals Impact of climate and moonlight on a venomous mammal, the Javan slow loris (Nycticebus javanicus Geoffroy, 1812)

2014 ◽  
Vol 83 (4) ◽  
pp. 217-225 ◽  
Author(s):  
Eva Johanna Rode-Margono ◽  
K. Anne-Isola Nekaris
Keyword(s):  
Climatic Factors ◽  
Prey Availability ◽  
Interactive Effect ◽  
Weather Conditions ◽  
Climatic Conditions ◽  
Activity Level ◽  
Environmental Data ◽  
Foraging Efficiency ◽  
Slow Loris ◽  
Reduce Activity

Predation pressure, food availability, and activity may be affected by level of moonlight and climatic conditions. While many nocturnal mammals reduce activity at high lunar illumination to avoid predators (lunarphobia), most visually-oriented nocturnal primates and birds increase activity in bright nights (lunarphilia) to improve foraging efficiency. Similarly, weather conditions may influence activity level and foraging ability. We examined the response of Javan slow lorises (Nycticebus javanicus Geoffroy, 1812) to moonlight and temperature. We radio-tracked 12 animals in West Java, Indonesia, over 1.5 years, resulting in over 600 hours direct observations. We collected behavioural and environmental data including lunar illumination, number of human observers, and climatic factors, and 185 camera trap nights on potential predators. Nycticebus javanicus reduced active behaviours in bright nights. Although this might be interpreted as a predator avoidance strategy, animals remained active when more observers were present. We did not find the same effect of lunar illumination on two potential predators. We detected an interactive effect of minimum temperature and moonlight, e.g. in bright nights slow lorises only reduce activity when it is cold. Slow lorises also were more active in higher humidity and when it was cloudy, whereas potential predators were equally active across conditions. As slow lorises are well-adapted to avoid/defend predators by crypsis, mimicry and the possession of venom, we argue that lunarphobia may be due to prey availability. In bright nights that are cold, the combined effects of high luminosity and low temperature favour reduced activity and even torpor. We conclude that Javan slow lorises are lunarphobic – just as the majority of mammals.

Enhanced Mobility of Organic Field-Effect Transistors with Epitaxially Grown C60 Film by in-situ Heat Treatment of the Organic Dielectric

2005 ◽  
Vol 871 ◽  
Author(s):  
Th. B. Singh ◽  
N. Marjanovic ◽  
G. J. Matt ◽  
S. Günes ◽  
N. S. Sariciftci ◽  
...  
Keyword(s):  
Thin Film ◽  
Electric Fields ◽  
Field Effect ◽  
Film Growth ◽  
Field Effect Transistors ◽  
Growth Conditions ◽  
Initial Growth ◽  
Organic Field Effect Transistors ◽  
Enhanced Mobility ◽  
High Electric Fields

AbstractElectron mobilities were studied as a function of thin-film growth conditions in hot wall epitaxially grown C60 based field-effect transistors. Mobilities in the range of ∼ 0.5 to 6 cm2/Vs are obtained depending on the thin-film morphology arising from the initial growth conditions. Moreover, the field-effect transistor current is determined by the morphology of the film at the interface with the dielectric, while the upper layers are less relevant to the transport. At high electric fields, a non-linear transport has been observed. This effect is assigned to be either because of the dominance of the contact resistance over the channel resistance or because of the gradual move of the Fermi level towards the band edge as more and more empty traps are filled due to charge injection.

Effects of salamander larvae on food webs in highly subsidised ephemeral ponds

Hydrobiologia ◽  
2017 ◽  
Vol 799 (1) ◽  
pp. 37-48 ◽  
Author(s):  
Timm Reinhardt ◽  
Mario Brauns ◽  
Sebastian Steinfartz ◽  
Markus Weitere
Keyword(s):  
Food Webs ◽  
Ephemeral Ponds ◽  
Salamander Larvae

The Effect of Initial Growth Conditions on the Tilting of Lattice Planes in InP-ON-GaAs Heterostructures

1991 ◽  
Vol 238 ◽  
Author(s):  
Ferenc Riesz ◽  
K. Lischka ◽  
K. Rakennus ◽  
T. Hakkarainen ◽  
A. Pesek ◽  
...  
Keyword(s):  
Growth Conditions ◽  
Initial Growth ◽  
Lattice Plane ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
Gas Source ◽  
Gaas Substrates ◽  
Nucleation Model ◽  
Lattice Planes ◽  
Lower Temperature

ABSTRACTThe relative misorientation (tilt) between the epilayer and substrate (400) lattice planes of InP epilayers grown by gas-source molecular beam epitaxy on (100) GaAs substrates misoriented towards the (110) plane was studied by high resolution x-ray diffraction. For the growth temperature of 490–500°C, the direction of the relative tilt was nearly coincident with the direction of the substrate lattice plane tilting. In contrary, when a buffer layer was deposited at a lower temperature of 400–450°C prior to growth, an azimuthal rotation of about 45° was found between the directions of the relative tilt and the substrate lattice plane tilting. In order to explain the results, a temperature-dependent anisotropic nucleation model is proposed.

Mosaic Crystal Tilts and Their Relationship to Dislocation Structure, Surface Roughness and Growth Conditions in Relaxed SiGe Layers

1998 ◽  
Vol 533 ◽  
Author(s):  
D. J. Wallis ◽  
D. J. Robbins ◽  
A. J. Pidduck ◽  
G. M. Williams ◽  
A. Churchill ◽  
...  
Keyword(s):  
Surface Roughness ◽  
High Performance ◽  
Surface Defects ◽  
Growth Conditions ◽  
Buffer Layers ◽  
Great Promise ◽  
Threading Dislocation ◽  
Initial Growth ◽  
Growth Interface ◽  
Mosaic Crystal

AbstractIn recent years the growth of virtual substrates using graded SiGe buffer layers has shown great promise for the development of high performance devices. Whilst significant progress has been made in the control of growth conditions to produce low threading dislocation densities of the order suitable for commercial exploitation, several technological problems still have to be overcome. An example of such problems are cosmetic surface defects such as pits and the cross hatched surface roughness associated with mosaic crystal tilts. The work described here utilises a variety of techniques, including X-ray diffraction reciprocal space maps, TEM, AFM and SIMS to provide a comparison between several SiGe virtual substrates grown using low pressure-CVD at high (≈800°C) and low (≈6000°C) temperatures, and at different grade rates (5–50% Ge μm−1). The growth conditions are seen to have a strong effect on the crystal tilts present in the layers with the low temperature layers showing a much larger spread of mosaic tilts. The origin of these tilts is seen to occur during the early stages of the relaxation process irrespective of growth temperature and at similar Ge fractions for all samples. TEM imaging close to the initial growth interface shows that dislocation pileups occur in this region and also suggest that the pileups have a characteristic spacing of 1–2μm. A similar characteristic length scale is also observed in the surface roughness by AFM, the form of which is seen to depend upon the growth conditions.

Echolocation and foraging behaviour in the Hawaiian hoary bat, Lasiurus cinereus semotus

1984 ◽  
Vol 62 (11) ◽  
pp. 2113-2120 ◽  
Author(s):  
Jacqueline J. Belwood ◽  
James H. Fullard
Keyword(s):  
Prey Availability ◽  
Weather Conditions ◽  
Peak Frequency ◽  
Social Signals ◽  
Lasiurus Cinereus ◽  
Social Signal ◽  
Term Basis ◽  
Strong Winds ◽  
High Degree ◽  
Lasiurus Cinereus Semotus

Free-flying individual Lasiurus cinereus semotus were observed as they foraged near incandescent lights on the island of Kauai, Hawaii. Two types of vocalizations were recorded from the bats: an echolocation–hunting signal with peak frequency of 27.8 kHz and an agonistic social signal, emitted while the bats were in aggressive pursuit of one another, with a peak frequency of 9.6 kHz. The tendency to vocalize agonistically increased with increased numbers of bats in the foraging area and increased as the density of insects available to the hunting bats decreased. Our observations suggest that the bats may gather echolocation information from their social signals. The bats at the site foraged under most weather conditions, including fog, moderate rain, strong winds, and temperatures as low as 13 °C. Groups of up to eight animals were common, although bats hunted in airspaces that were vigorously defended against other individuals. Small flies and small moths (< 10 mm body length) were the most common insects available as prey, but larger moths (16–20 mm) made up the bulk of the bats' diet. Moths larger than 20 mm were available but not fed on by the bats. This unique study site provides a rare opportunity to compare both prey availability to prey consumption in a population of bats. Our results suggest that this bat, at least on a short-term basis, exhibits a high degree of selectivity in its foraging, a behaviour similar to the mainland subspecies.

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