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The use of botanical products such as essential oils has gained prominence as a control method as they have insecticidal properties that can be used in the management of pests such as Neoleucinodes elegantalis (Guenee) (Lepidoptera Crambidae). Combining chemical and botanical products with natural enemies is a desirable strategy for managing this pest species. Trichogramma pretiosum Riley (Hymenoptera Trichogrammatidae) is a potential biological control agent for N. elegantalis. In this study, the objective was to evaluate the toxicity of Pelargonium graveolens L. and Amyris balsamifera L. oils on N. elegantalis, and the sublethal effects of the oils and the insecticides azadirachtin and deltamethrin on biological parameters of T. pretiosum, as well as to determine their selectivity and functional response. Chemical analysis reveals that the chemical profile of the A. balsamifera is dominated by sesquiterpenes, whereas for P. graveolens it is monoterpenes. The LC50 (0.078 µL/mL for A. balsamifera and 0.0081 µL/L for P. graveolens) and LC30 (0.032 µL/mL for A. balsamifera and 0.0034 µL/mL for P. graveolens) were estimated, indicating that they have a toxic effect on N. elegantalis eggs. A. balsamifera oil and the insecticide deltamethrin affected T. pretiosum parasitism. The type of functional response of T. pretiosum on host eggs treated with essential oils followed type II as in the control, whereas on host eggs treated with azadirachtin a type III functional response was exhibited. P. graveolens presented the best result for use in association with the parasitoid in pest management, being a promising alternative. [ABSTRACT FROM AUTHOR]

Climate change projections suggest a precarious future for the Monarch butterfly (Danaus plexippus) as the suitable climatic habitat of its exclusive overwintering host Abies religiosa (oyamel, Sacred fir, a conifer endemic to Mexico) inside the Monarch Butterfly Biosphere Reserve (MBBR) is expected to disappear by 2090. Since the upper elevation limit of A. religiosa is approximately 3,500 m and the summits of mountains within the MBBR are ca. 3,550 m, we tested the feasibility of establishing A. religiosa at four locations outside its current geographic range in the MBBR, on a geographically close volcano, Nevado de Toluca at 4000 (timberline, an extreme site), 3,800, and 3,600 m (to test species range expansion upward in elevation), and at 3400 m (a reference site, slightly lower than the upper elevation limit of A. religiosa). Using existing shrubs as nurse plants to protect the seedlings from extreme temperatures, at each site we planted five to eight populations, originating between 3,100 and 3,500 m within the MBBR. After three growing seasons in the field (6 years after sowing), we found that: (a) survival and height increment declined steeply with test site elevation; (b) even at the highest sites (3,800 and 4,000 m), survival was acceptable, at 68 and 44%, respectively, although the growth was very poor at 4000 m; (c) populations responded similarly to transfer; (d) transfer effects were best accounted for by annual dryness index; (e) to compensate for the expected 2.3°C increase in mean annual temperature or 0.009 √°Cmm-1 increase of annual dryness index from the reference period (1961-1990) to the decade centered in 2060, it would be necessary to shift populations approximately 500 m to higher elevations; and (f) upward transfers to compensate for the 2.3°C increase in mean annual temperature are expected to result in height increment and survival that are approximately 47 and 21% lower, respectively, than values expected at zero transfer distance. We conclude that the establishment of A. religiosa at 3600 and 3,800 m is feasible and that planted stands could eventually serve as overwintering sites for the Monarch butterfly under projected future climates. [ABSTRACT FROM AUTHOR]

The monitoring of neutron ambient dose equivalent rate in a radiation field is of significant importance as it can reflect the operational status of nuclear facilities and provide radiation protection information. Currently, the commonly used monitoring instrument is the A-B type dose equivalent rate meter based on a single detector and a single moderator. However, its response curve differs from the “neutron fluence-ambient dose equivalent conversion coefficient,” leading to measurement errors. In this study, in order to improve the accuracy of neutron dosimeter measurement, a feasibility study was carried out on the joint monitoring of neutron dose rate based on neutrons and instant γ-rays. Lead, borated polyethylene, polymethyl methacrylate, and sodium chloride were used to establish a conversion object. Monte Carlo simulations were performed to calculate the neutron responses of elements B, H, Cl, Pb, C and O. Then, these response curves were combined with the response curves of the LB6411 dosimeter to obtain a new response curve closer to the “neutron fluence-ambient dose equivalent conversion coefficient”. The linear fitting coefficients were calculated by using the differential evolution algorithm. The results demonstrate that the modified response curve is closely to the \begin{document}$h_{\phi} $\end{document} response curve. The relative discrepancies are within 50% for the energy range of 1×10−8-16 MeV. The study indicates the feasibility of joint measurement of neutron and prompt gamma-ray for monitoring neutron ambient dose equivalent rate, providing new directions and support for neutron dosimeter calibration and development.

[Objective] To study the photosynthetic characteristics of Citrus aurantium in summer. [Method] By using Li-6400 portable photosynthesis system, the net photosynthetic rate (Pn) of leaves in different positions, diurnal variation of photosynthesis, light response curve and CO2 response curve of Citrus aurantium were measured. [Result] There were certain differences in Pn of leaves in different directions and parts. The diurnal variation of Pn of Citrus aurantium in summer showed a double-peak curve with a “nap” phenomenon, and the photosynthetic peaks appeared at 10:00 and 14:30, respectively. The diurnal variation of stomatal conductance was similar to that of Pn. From the light response curve, it could be seen that Citrus aurantium had a high saturation point and a light intensity of 0-2 000 μmol/ (m²·s), the Pn continued to increase, reaching a maximum of 13.44 μmol/ (m²·s), with a light compensation point of 28.33 μmol/ (m²·s), the apparent quantum efficiency was 0.036. From CO2 response curve, the CO2 saturation point and CO2 compensation point were about 1 500 μmol/mol and 60.65 μmol/mol, respectively, and the carboxylation efficiency was 0.079. The results of correlation and regression analysis showed that in summer Pn of Citrus aurantium was closely associated with physiological and ecological factors, such as stomatal conductance, relative humidity, intercelluar CO2 concentration, transpiration rate, vapor pressure deficienc. [Conclusion] Citrus aurantium was a heliophile C3 plant and it had a strong ability to adapt and utilize low light and strong assimilation ability to CO2. And under the high temperature and low air relative humidity in summer, the photosynthesis of Citrus aurantium was affected by various physiological and ecological factors. In this period, the photosynthetic active radiation was not the key factor affecting Pn, and the air relative humidity was significantly positively correlated with Pn. Therefore, environmental selection or cultivation measures to increase the air relative humidity could mitigate the midday depression of photosynthesis in summer and improved the photosynthetic efficiency of Citrus aurantium. [ABSTRACT FROM AUTHOR]

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Fricke gel dosimeters obtained by modifications on standard Fricke dosimeter presents some advantages like easy preparation, tissue equivalence, good reproducibility and dose mapping. In this work, dose response characteristics of Gelatin Fricke gel dosimeters was investigated and compared with Fricke agarose gel dosimeters in terms of sesitivity. After prepration of three different formulation of Gelatin Fricke gel dosimeters and gamma irradiation of the samples, a spectrophotometer was applied to measure the optical absorbance of the samples. Results indicate a linear dose range response of 10 to 30 Gy, as well as increased gelatin concentrations cause the sensitivity of the dosimeter to detereorate with a 80% reduction of dose response for a change in gelatin concentration from 3 to 8 weight percent. Obtained coefficient variation verifies the good repeatability of the gel response. The gel dosimeter has no dose rate dependence. Comparison of the most sensitive Gelatin Fricke gel sample with the prepared Fricke agarose gel samples confirm that Fricke agarose dosimeter is more sensitive than Gelatin Fricke gel dosimeter. [ABSTRACT FROM AUTHOR]

Invasive insect species threaten the productivity of ecosystems worldwide, and ecological niche models can be used to predict distributions of invaders and guide management efforts. Ecological niche models can also aid monitoring for invasive species that are globally distributed. One such species is the yellow spotted stink bug (Erthesina fullo Thunberg), a polyphagous pest native to Asia that has established in Europe and South America and threatens specialty crops. Here, we used ecological niche models to predict the potential distribution of E. fullo, and created a website to display predictions. We show that E. fullo has peak occurrence probability in areas with annual mean temperatures around 20°C, and that the occurrence probability increases as maximum monthly temperature reaches up to 38°C. The likelihood of occurrence decreased as annual precipitation increased, but increased with greater precipitation in the wettest and driest months. This suggests E. fullo is most suited to regions that are warm and dry and where most precipitation occurs across only a few months, such as southern North America, central and southern South America, southern Europe, southern Africa, and central and eastern Australia. Given that E. fullo is a highly mobile hitchhiking insect that travels through cargo and other containers to new areas, the potential spread of this species into new regions should be carefully monitored. [ABSTRACT FROM AUTHOR]

Background: To explore the reason and treating method for the negative value of uric acid in a patient patient. Methods: The serum of a patient with a negative uric acid detection value was diluted 5 times with "sterilized water" and with "normal saline". Additionally, the serum was treated with PEG6000 protein, and uric acid was detected. Results: Elevated IgM paraprotein in the patient resulted in abnormal uric acid response curves in serum samples or diluted serum samples. After the serum was precipitated with PEG600, the uric acid response curve was basically normal. Conclusions: The negative value of the patient's uric acid test was caused by the IgM paraprotein. After removing the interference by PEG6000 protein a true and accurate uric acid result was obtained. [ABSTRACT FROM AUTHOR]

For the free vibrations of multi-degree mechanical structures appeared in structural dynamics, we solve the quadratic eigenvalue problem either by linearizing it to a generalized eigenvalue problem or directly treating it by developing the iterative detection methods for the real and complex eigenvalues. To solve the generalized eigenvalue problem, we impose a nonzero exciting vector into the eigen-equation, and solve a nonhomogeneous linear system to obtain a response curve, which consists of the magnitudes of the n-vectors with respect to the eigen-parameters in a range. The n-dimensional eigenvector is supposed to be a superposition of a constant exciting vector and an m-vector, which can be obtained in terms of eigen-parameter by solving the projected eigen-equation. In doing so, we can save computational cost because the response curve is generated from the data acquired in a lower dimensional subspace. We develop a fast iterative detection method by maximizing the magnitude to locate the eigenvalue, which appears as a peak in the response curve. Through zoom-in sequentially, very accurate eigenvalue can be obtained. We reduce the number of eigen-equation to n−1 to find the eigen-mode with its certain component being normalized to the unit. The real and complex eigenvalues and eigen-modes can be determined simultaneously, quickly and accurately by the proposed methods.

Distribution of 211 species and larger taxa of benthic animals is considered along the gradient of chemical contamination in bottom sediments (by TPF index) on the data of long-term observations (1992–2019), using hierarchical Hausman-Olf-Fresco logistic regression models. Frequency of occurrence and density in settlements are used as the quantitative measures of the macrozoobenthos distribution. Parameters of the species relation to contamination are determined, as mean coordinate of the response curves, position of the optimum, and width of the outer and central niches. By these parameters, using the fuzzy sets algorithm, the taxa are classified to five groups: i) extremely sensitive; ii) highly sensitive; iii) moderately tolerant; iv) tolerant; and v) extremely tolerant to pollution (ES, S, MT, T and ET, respectively). Both stenobionts, steno-eurybionts and eurybionts are presented in each group, but the stenobionts dominate in ES and S groups and the eurybionts prevail in T and ET groups, being the opportunists of the II and I order, while the taxa of different biontity are equally presented in MT group. The classification could be used for interpretation of changes in composition and structure of macrozoobenthos in the areas subjected to anthropogenic pollution.

Amazônia is a species-rich region of immense importance to Earth's water and carbon cycling. Photosynthesis drives the global carbon cycle, so understanding photosynthetic differences across diverse landscapes is a key task of ecophysiology and ecosystem science. Unfortunately, due to physiological and logistical constraints, ground-based photosynthesis data in Amazônia remains scarce, and the 'traditional' steady-state method (SS) of gas exchange is slow and inefficient. The Dynamic Assimilation™ Technique (DAT; Saathoff and Welles 2021) promises a new way to perform A/Ci curves rapidly without requiring steady-state conditions. Thus far, this technique has only been validated in greenhouse or agricultural-field-grown species and has yet to be tested in forest trees of diverse physiology, morphology, and environmental adaptation. To test the utility of the DAT in a complex tropical forest ecosystem, we compared the DAT to the SS method in 13 Amazonian trees in situ. We found strong agreement between Vcmax from DAT curves and SS curves, while Jmax was underestimated in DAT curves. We conclude that the DAT provides a robust and rapid estimation of Vcmax. We also identified diverse and unexpected DAT curve shapes among some trees, including the presence of an 'overshoot' in assimilation beyond model-derived RuBP regeneration limitations. The presence of overshoot may elucidate microclimate and species differences in RuBP regeneration rates and emphasizes the considerable importance of DAT curve protocol specifications, such as the effect of ramp rate and direction on Jmax and TPU. Overall, the DAT saved time relative to the SS method and proved to be an effective and rapid method for quantifying Vcmax in tropical trees., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Understanding the ecological characteristics of plant species and how they respond to environmental factors provides information necessary for vegetation and rangeland management. Due to the importance of Salsola kerneri (Wol) Botsch species in soil protection and forage production, in this article, its ecological needs are studied with an emphasis on determining ecological factors affecting vegetation changes and investigating the response of this species to changes using Canonical Correspondence Analysis (CCA) and Generalized Additive Models (GAM) in Mazandaran province. The results of Canonical Correspondence Analysis (CCA) showed that environmental factors such as percentage of clay, soil sand, geographical direction, acidity, percentage of saturated moisture, percentage of organic matter, percentage of soil lime, and average annual temperature in the studied habitats, respectively, with the expression of 10.3, 2.8, 4.1, 3.3, 1.6, 1.4, 1.3 and 1.4% of the variance in the plant composition had an important role in the vegetation changes in the studied habitats. The results showed that the response of S. kerneri species to organic matter percentage, organic carbon percentage, soil nitrogen percentage, and soil litter percentage follows the monotonic decrease model. The response pattern of S.kerneri along the clay (%), soil specific gravity, altitude, mean annual temperature, potassium (ppm), and phosphorus (ppm) followed the unimodal model, and its optimum growth rate for these factors was 11%, 1.1 g/cm3,13C°,1700m,12.5°C, 700 ppm, and 5 ppm respectively. The response of the species to the geographical direction is such that the eastern slopes have the highest percentage of vegetation and the northeastern slopes have the lowest percentage. It is distributed in lands with high to relatively high slopes, but it has better performance in slopes of 40-50%, although the response of the species to this factor was not significant. The species response to the percentage of soil sand and silt and stone and gravel followed the bimodal model. The study of the reaction of the species along the slope of the topographic and soil factors provided valuable information to determine the ecological needs of this species, which can be taken into consideration in the rangeland's improvement operations in similar areas. [ABSTRACT FROM AUTHOR]

The leaf photosynthesis models developed by Farquhar et al. (1980, https://doi.org/10.1007/BF00386231) (FvCB) and Goudriaan et al. (1985, https://doi.org/10.1007/978‐1‐4899‐3665‐3%5f10) (G85) are both used in Earth system and weather models to quantify ecosystem carbon assimilation. Despite their common role, a systematic comparison between these two photosynthesis models is currently lacking in scientific literature. In this technical report we compared the two models in a systematic way. Hereto we performed a comparative analysis of the model structures as well as the modeled responses of photosynthesis to light and CO2 at leaf level. To facilitate future model comparison, we also constructed a lookup table that presents FvCB model parameters fitted to CO2‐response curves from G85 in a wide natural range in photosynthetic capacity at standardized temperature. The structure of the FvCB model differs fundamentally from the G85 model as the FvCB model considers rate‐limiting processes due to Rubisco capacity, electron transport and triose phosphate utilization in parallel, whereas the G85 model considers Rubisco activity and triose phosphate utilization limitation to act in series scaled with quantum use efficiency. The models also differ fundamentally in terms of the parametrization of dark respiration. Still, both models calculate near‐similar responses of photosynthesis to changes in light and CO2 across a wide range in photosynthetic capacity with only two free parameters each. Our work thereby highlights functional similarities between these model approaches despite fundamental differences in model structure. Hence, standardized parameter sets that yield similar photosynthesis responses to light and CO2 may facilitate intercomparison of Earth system and weather models. Plain Language Summary: In Earth system and weather models the exchange of CO2 between the vegetation and the atmosphere is primarily determined by photosynthesis at leaf level. Two commonly applied representations of leaf photosynthesis are based on the models of Farquhar et al. (1980, https://doi.org/10.1007/BF00386231) (FvCB) and Goudriaan et al. (1985, https://doi.org/10.1007/978‐1‐4899‐3665‐3%5f10) (G85). A systematic comparison between the two model approaches is currently lacking in scientific literature. The objective of our technical report is to provide such a comparison and thereby to contribute to an exchange of ideas, data and applications between users of the respective models. We found that the two models calculate a similar response of net photosynthesis to light and CO2, despite having considerable differences in their model structure and representation of physiological processes. The main difference in model structure is that the limitations to photosynthesis in the FvCB model are applied in parallel, whereas in the G85 model they are in series. We also present a lookup table to express parameters from the G85 model in terms of their equivalent FvCB parameters. This technical report thereby contributes to the comparison of models used across the Earth system and weather modeling communities. Key Points: We compare two leaf photosynthesis models, based on different biophysical assumptions, that are both used in Earth system and weather modelingThe two models calculate a near‐similar response of net photosynthesis to light and CO2 despite having considerable differences in their structure and process representation. This finding is significant across a wide range of naturally occurring photosynthetic capacities in vegetationThrough a flowchart, a comparison of photosynthetic response to light and CO2 and a parameter conversion table, we aim to enable more communication and exchange of data between users of the two models within the Earth system and weather modeling communities [ABSTRACT FROM AUTHOR]

Purpose: The aim of this work is to study a new analytical model which describes the dose–response curve in megavoltage photon beams of the radiochromic EBT3 film measured with two commercially available flatbed scanners. This model takes into account the different increase of the number of two types of absorbents in the film with absorbed dose and it allows to identify parameters that depend on the flatbed scanner and the film model, and parameters that exclusively depend on the production lot. In addition, the new model is also compared with other models commonly used in the literature in terms of its performance in reducing systematic calibration uncertainties. Methods and materials: The new analytical model consists on a linear combination of two saturating exponential functions for every color channel. The exponents modeling the growing of each kind of absorbent are film model and scanner model‐dependent, but they do not depend on the manufacturing lot. The proposed model considers the different dose kinetics of each absorbent and the apparent effective behavior of one of the absorbents in the red color channel of the scanner. The dose–response curve has been measured using EBT3 films, a percentage depth dose (PDD) calibration method in a dose range between 0.5 and 25 Gy, and two flatbed scanners: a Microtek 1000 XL and an EPSON 11000 XL. The PDD calibration method allows to obtain a dense collection of calibration points which have been fitted to the proposed response curve model and to other published models. The fit residuals were used to evaluate the performance of each model compared with the new analytical model. Results: The model presented here does not introduce any systematic deviations up to the degree of accuracy reached in this work. The residual distribution is normally shaped and with lower variance than the distributions of the other published models. The model separates the parameters reflecting specific characteristics of the dosimetry system from the linear parameters which depend only on the production lot and are related to the relative abundance of each type of absorbent. The calibration uncertainty is reduced by a mean factor of two by using this model compared with the other studied models. Conclusions: The proposed model reduces the calibration uncertainty related to systematic deviations introduced by the response curve. In addition, it separates parameters depending on the flatbed scanner and the film model from those depending on the production lot exclusively and therefore provides a better characterization of the dosimetry system and increases its reliability. [ABSTRACT FROM AUTHOR]

Introduction: Parapholis incurva is a plant in halophytic rangelands of the northern Golestan Province and is very important in terms of forage production. This plant species grows in arid climates and saline soils. The aim of this study was to investigate the relationship between the characteristics of this species with environmental factors such as soil physicochemical properties and distance from the watering trough in rangelands of Incheh Borun in Golestan Province.Material and methods: Towards this attempt, 200 quadrates with an area of 4 m2 were taken along distances from a watering trough. The sampling method was randomized-systematic. In the sampling area, the presence of P. incurva species was recorded. In the center of each plot, the soil was sampled from depths of 0 to 20 centimeters. Soil samples were transferred to the laboratory and experiments were carried out to measure pH, electrical conductivity (EC), soil texture (silt, clay, and sand), organic carbon, nitrogen, and phosphorus. In this research pH, EC, soil texture, organic carbon, nitrogen, and phosphorus were measured using pH meter, conductivity meter, hydrometric method, and Olson method, respectively. Multiple regression analysis (using SPSS software V18) was used to investigate the relationship between the characteristics of P. incurva and distances from a watering trough and soil physicochemical properties. Results and discussion: R2 values (93%) showed that distances from a watering trough had the most contribution to the variations in density, percentage cover, and frequency changes. The strength of the linear regression model by soil parameters for predicting the density, percentage cover, and frequency of P. incurva was 77, 70 and 83 percent, respectively. Results showed soil properties such as total nitrogen, sand content, and organic matter content had a positive effect on the presence of P. incurva in the study area. The results showed that pH, Buckley density, silt content, and EC had a negative effect on the presence and distribution of P. incurva.Conclusion: On a local scale, distance from a watering trough was more influential on the changes in density, percentage cover, and frequency of P. incurva than soil parameters.

Understanding the ecological characteristics of plant species and how they react to environmental factors provides the necessary information for vegetation management and rangeland improvement. In the present study, the ecological needs of sainfoin (Onobrychis melanotricha Boiss.) were studied with emphasis on environmental factors affecting vegetation changes, and the response of this species to changes in ecological factors was investigated using the Canonical Correspondence Analysis (CCA). Data collection was performed in 2018 in 19 study sites in the west and south of Isfahan province. In each site, the vegetation sampling was performed by random-systematic sampling method in 30 plots of one square meter, located along 3 200-meter transects, and soil sampling was done from a depth of 0-30 cm in each site. Data were analyzed using SPSS17 and CANOC4.5 software. Using a generalized additive model with Poisson error distribution for each of the environmental variables showed that environmental factors including height, clay percentage, rainfall, organic matter percentage, phosphorus, and sand percentage, and the average annual temperature significantly affect (p<0.01) vegetation. This species is distributed on semi-deep to deep soils with medium to semi-heavy textures. This species is distributed on semi-deep to deep soils with medium to semi-heavy textures. The optimal altitude range for the growth of this plant was 1600-3200 meters above sea level, and the optimal rainfall for this plant was 370 mm. Overall, the results of this study had an acceptable efficiency in determining the ecological needs of the species, which can be considered by natural resource managers in vegetation management and rangeland improvement operations in similar areas. [ABSTRACT FROM AUTHOR]

In the present study, Taguchi design of experiments (DOEs) L18 orthogonal array has been used for the investigation of the mechanical behavior of rigid polyurethane foam (RPUF) composites. The outcome of the process parameters such as polyol, filler, surfactant, catalyst, blowing agent, and anti-flaming agent on the mechanical properties, such as tensile, flexural, and compressive strengths and hardness (Shore D) of RPUF composites, has been examined, and the resulted data were analyzed by means of Taguchi design of experiments. The raw data for the average values of the mechanical properties and the signal-to-noise (S/N) ratio for each parameter were evaluated at three levels, and the analysis of variance (ANOVA) and optimum process parameters are determined. The confirmation experiments were performed for the validation of the improved performance and to measure the contribution of individual parameter on the responses. The confirmation experiments revealed the average tensile strength, average compressive strength, average flexural strength, and average hardness (Shore D) as 5.24 MPa, 6.37 MPa, 12.28 MPa, and 72.43, respectively, which fall within the 95% confidence interval of the anticipated optimum process parameters. [ABSTRACT FROM AUTHOR]

The impact of water stress and nitrogen (N) nutrition on leaf respiration (R), carbon balance and water use efficiency (WUE) remains largely elusive. Therefore, the objective of the present study was to investigate the effect of soil water and N stresses on growth, physiological responses, leaf structure, carbon gain and WUE of maize. The plants were subjected to different soil water and N regimes to maturity. The results showed that the photosynthesis (A n) and stomatal conductance (G s) decreased significantly under the water stressed treatments across the N treatments mainly ascribed to the decreased plant water status. The moderate water stress reduced the photosynthetic capacity and activity and also caused damage to the structure of leaves, resulting in the significant reduction of A n , and thus decreased WUE i. The dark respiration (R d) was significantly decreased due to the damage of mitochondria, however, the R d /A n increased significantly and the carbon gain was seriously compromised, eventually inhibiting biomass growth under the moderately water stressed treatment. Increasing N dose further aggravated the severity of water deficit, decreased A n , G s and WUE i , damaged the structure and reduced the number of mitochondria of leaves, while increased R d /A n considerably under moderate water stress. Consequently, the biomass accumulation, carbon gain and plant level WUE p in the moderately water stressed treatment decreased markedly under the high N supply. Therefore, excessive N application should be avoided when plants suffer soil water stress in maize production. 1. Moderate water stress significantly decreased dark respiration by damaged mitochondria. 2. Moderate water stress broke the carbon balance eventually inhibiting plant growth. 3. High N supply further aggravated drought severity, decreased carbon gain and WUE. 4. Excessive N application should be avoided when plants suffer water stress. [ABSTRACT FROM AUTHOR]

Understanding the ecological characteristics of plant species and how they respond to environmental factors provides the information needed to manage vegetation and restore rangeland ecosystems. This study aimed to determine environmental factors affecting the habitat of Krascheninnikovia ceratoides (L.) species and its response to changes in ecological factors in the rangelands of Isfahan province. Accordingly, canopy cover and density of K.ceratoides and the associated species were measured in 19 ecological sites using a random systematic sampling method. In each site, climate, physiography, and soil factors were identified. Canonical Correspondence Analysis (CCA) and Generalized Additive Models (GAM) using CANOC4.5 software were used to investigate the vegetation relationship with environmental factors. The results showed that the response pattern of K. ceratoides along the gradient of absorbable potassium follows the incremental model. Conversely, the response of this species along the gradient of sand percentage, average annual temperature, and rock and gravel percentage has followed a decreasing model, and with increasing these factors, the percentage of canopy cover has decreased. The response pattern of K. ceratoides, along with the changes of the amount of absorbed phosphorus, the percentage of gypsum, and the altitude of the sea follow the bell model (Unimodal), and its optimal growth limit for these factors is 10 mg kg-1, 6.4%, and 2250 meters. The study of K. ceratoides species response along the gradient of topographic, soil, and climate factors provided valuable information to determine the ecological needs of this species that can be considered in vegetation management and rangeland improvement operations in similar areas. [ABSTRACT FROM AUTHOR]

Why this research Matters: Phenotypic plasticity is a key mechanism for sedentary long‐living species to adjust to changing environment. Here, we use mature Larix decidua tree‐ring variables collected along an elevational transect in the French Alps to characterize the range of individual plastic responses to temperature. Stem cores from 821 mature Larix decidua trees have been collected from four plots distributed along a 1,000‐m elevational gradient in a natural forest to build up individual linear reaction norms of tree‐ring microdensity traits to temperature. The sign, magnitude and spread of variations of the slopes of the individual reaction norms were used to characterize variation of phenotypic plasticity among plots and traits. Results showed a large range of phenotypic plasticity (with positive and negative slopes) at each elevational plot and for each tree‐ring variable. Overall, phenotypic plasticity tends to be larger but positive at higher elevation, negative at the warmer lower sites, and more variable in the center of the elevation distribution. Individual inter‐ring reaction norm is a valuable tool to retrospectively characterize phenotypic plasticity of mature forest trees. This approach applied to Larix decidua tree‐ring micro‐density traits along an elevation gradient showed the existence of large inter‐individual variations that could support local adaptation to a fast‐changing climate. [ABSTRACT FROM AUTHOR]

As humans clear natural habitat, they are brought into increased conflict with wild animals. Some conflict is direct (e.g. elevated exposure of people to predators), some indirect (e.g. abandoning suitable habitat because of human activity). The magnitude of avoidance is expected to track frequency of human activity, but the type of response is an open question. We postulated that animals do not respond passively to increased disturbance nor does response follow a power law; instead, their ability to estimate magnitude leads to 'discounting' behaviour, as in classic time-to-reward economic models in which individuals discount larger value (or risk) in more distant time. We used a 10-year camera dataset from southern California to characterize response curves of seven mammal species. Bayesian regressions of two non-discounting models (exponential and inverse polynomial) and two discounting models (hyperbolic and harmonic) revealed that the latter better fit response curves. The Arps equation, from petroleum extraction modelling, was used to estimate a discount exponent, a taxon-specific 'sensitivity' to humans, yielding a general model across species. Although discounting can mean mammal activity recovers rapidly after disturbance, increased recreational pressure on reserves limits recovery potential, highlighting a need to strike a balance between animal conservation and human use.

Abstract Climate warming and habitat transformation are widely recognized as worrying threatening factors. Understanding the individual contribution of these two factors to the change of species distribution could be very important in order to effectively counteract the species range contraction, especially in mountains, where alpine species are strongly limited in finding new areas to be colonized at higher elevations. We proposed a method to disentangle the effects of the two drivers of range change for breeding birds in Italian Alps, in the case of co‐occurring climate warming and shrub and forest encroachment. For each species, from 1982 to 2017, we related the estimated yearly elevational distribution of birds to the correspondent overall average of the daily minimum temperatures during the breeding season and the estimated amount of shrubs and forest cover. Using a hierarchical partitioning approach, we assessed the net contribution (i.e., without the shared effect) of each driver. Both temperature and shrub and forest cover showed a positive trend along the time series and resulted the most likely causes of the significant elevational displacement for 21 of the 29 investigated birds. While shrub and forest cover was found to be an important driver of the expansion of forest bird range toward higher elevations, the effect of temperature on favouring the colonization of previously climatically unsuitable forests at higher elevations was not negligible. Shrub and forest expansion resulted the main driver of the range contraction for edge and open habitat species, which suffered a distribution shrinkage at their lower elevational boundary. In light of climate warming, these results highlighted how the net range loss for edge and open habitat species, caused by shrub and forest encroachment consequent to land abandonment, should be counteracted by implementing proper conservation management strategies and promoting sustainable economic activities in rangeland areas.

Due to their beneficial, stimulating impact on plant growth, productivity, and alleviating environmental stresses, protein hydrolysates have recently received increasing attention as a possible substitute. This investigation aimed to explore the effects of foliar application of papain-produced whey protein hydrolysates (WPH) on the yield attributes and nitrogen use efficiency (NUE) of soft wheat. Wheat plants were cultivated under a Mediterranean arid environment and received four soil nitrogen (N) fertilization levels with ammonium nitrate (145, 185, 215, and 250 kg N ha−1) and compared to control treatment and urea foliar application. WPH increased grain yield, yield attributes, and N accumulation in wheat plants. Partial productivity factors of applied nitrogen, as NUE indicators under relatively steady-state cropping systems, were also enhanced by WPH compared to control treatment. WPH significantly improved flag leaf area, spike number m−2, and grain yield compared to urea foliar application. Increasing the soil N fertilization level from 145 up to 215 kg N ha−1 was accompanied by significant increases in all yield traits and N accumulation measurements, except for the partial factor productivity of applied N, which decreased. A strong positive association was detected among grain and straw yields, their attributes, and total N uptake. Results highlighted the efficacy of WPH in increasing wheat yield and NUE.

Investigation on the shape of the curve for responses of plant species to environmental gradients is one of the basic topics in the science of rangeland ecology. The objective of this study was investigation on the response of Bromus tomentellus and Festuca ovina species to some environmental variables using the generalized additive model (GAM) in the rangeland of Galandrood watershed in Mazandaran province. Towards this attempt, 153 quadrates of 1m2 along altitudinal gradient were taken. The sampling method was randomized-systematic. In the area sampled, presence of B. tomentellus and F.ovina, altitude, slope and aspect were recorded. Soil samples were taken from 0-20 cm in each quadrate. In each quadrate, soil properties including: pH, N, EC, organic carbon, the percentage of sand, silt and clay were measured. In order to study the shape of response curve in relation to the mentioned variables, GAM model was used with binomial distribution function. The data were analyzed by R ver.3.0.2 computer program. Results showed that altitude was the most important variable affecting the presence of B. tomentellus, While variables such as temperature and slope were the most important factors affecting the presence of F.ovina species. Clay and silt content in the soil were parameters that had significant negative impact on B. tomentellus and F.ovina species distribution. So, with an increase in clay and silt content of the soil, the possibility of the B. tomentellus and F.ovina presence were reduced.

Lytro cameras are equipped to capture 3D information in one exposure without the need for structured illumination, allowing greyscale depth maps of the captured image to be created using the Lytro desktop software. These consumer-grade light-field cameras (Lytro) provide a cost-effective method of measuring the depth of multiple objects which is suitable for many applications. But, the greyscale depth maps generated using the Lytro cameras are in relative depth scale and hence not suitable for engineering applications where absolute depth is essential. In this research, camera control variables, environmental sensitivity, depth distortion characteristics, and the effective working range of first- and second-generation Lytro cameras were evaluated. In addition, a depth measuring technique to deliver 3D output depth maps represented in SI units (metres) is discussed in detail exhibiting the suitability of consumer-grade Lytro cameras suitability in metrological applications without significant modifications. [ABSTRACT FROM AUTHOR]

Seeding rate for maximum grain yield can differ for diverse hard red spring wheat (HRSW) (Triticum aestivum L.) cultivars and is derived from a yield response curve to seeding rates. Six groups of HRSW cultivars with combinations of Rht-B, Rht-D, and Ppd-D genes were planted at five seeding rates in 21 environments during 2013−2015 throughout Minnesota and eastern North Dakota, USA. Seeding rates ranged from 1.59 to 5.55 million seeds ha−1 and planting timings were optimal and delayed dates. An analysis of covariance predictive model with 13 predetermined training environments was built for yield and tillering, and validated with eight predetermined environments. Optimal seeding rates from the yield model were not predictive for yield, with latitude of the environment negatively skewing the predictions from observed values. A second yield model fit to only the six lowest-yielding environments (−1) was more predictive (R2 = 0.44), and revealed yield response to seeding rate was influenced by cultivar traits for photoperiod response (Ppd-D gene) and plant stature (semi-dwarfing gene Rht-D). The tillering model was also predictive for the validation environments, with a R2 of 0.71. Using regression predictions for yield and tillering from training and validation datasets with HRSW genetic and geographic predictors shows promise to help recommend seeding rates for future environments.

Soil in Kalimantan Island is considered infertile. To obtain a reasonable crop yield a high input fertilizer package should be applied. The situation will be worsening when an open pit system of coal mining adopted. Failure in re-arranging the soil layers can result in decreasing soil fertility compared to original soil prior to mining. This study aimed to determine the improvement of soil fertility of a disposal without top soil by using composts from various sources, namely, the public garbage pile, commercial compost, and compost from kitchen waste. The experiment was conducted in a disposal area of a coal mining of PT AI. A series of application rate of compost was set. This was 0, 5, 10, and 20 tonne compost ha-1. A plot with top soil was involved for another control. Maize was selected as the plant indicator to evaluate the effect of treatments applied. It can be concluded that application of composts to reclamation area without top soil significantly improve soil fertility. Among the composts used, K-compost (compost from kitchen waste) was the best in improving soil fertility. There were some characters of the compost that had not enough to support maize yield. These were P, K, and pH. Addition of P and K fertilizers and lime material are needed. Of the equation coefficients obtained, the b coefficient of equation belong to K-compost was higher than of the others.

Climate warming and habitat transformation are widely recognized as worrying threatening factors. Understanding the individual contribution of these two factors to the change of species distribution could be very important in order to effectively counteract the species range contraction, especially in mountains, where alpine species are strongly limited in finding new areas to be colonized at higher elevations. We proposed a method to disentangle the effects of the two drivers of range change for breeding birds in Italian Alps, in the case of co‐occurring climate warming and shrub and forest encroachment. For each species, from 1982 to 2017, we related the estimated yearly elevational distribution of birds to the correspondent overall average of the daily minimum temperatures during the breeding season and the estimated amount of shrubs and forest cover. Using a hierarchical partitioning approach, we assessed the net contribution (i.e., without the shared effect) of each driver. Both temperature and shrub and forest cover showed a positive trend along the time series and resulted the most likely causes of the significant elevational displacement for 21 of the 29 investigated birds. While shrub and forest cover was found to be an important driver of the expansion of forest bird range toward higher elevations, the effect of temperature on favouring the colonization of previously climatically unsuitable forests at higher elevations was not negligible. Shrub and forest expansion resulted the main driver of the range contraction for edge and open habitat species, which suffered a distribution shrinkage at their lower elevational boundary. In light of climate warming, these results highlighted how the net range loss for edge and open habitat species, caused by shrub and forest encroachment consequent to land abandonment, should be counteracted by implementing proper conservation management strategies and promoting sustainable economic activities in rangeland areas. We quantified the change in the elevational distribution of birds breeding on Italian Alps; we evaluated the net contribution of climate and habitat on bird range changes; we identified the winners and the loser species in light of environmental changes occurred on Alps in the past four decades. [ABSTRACT FROM AUTHOR]

Abstract The altitudinal distribution of mountain birds has recently changed following different patterns in space and time, probably due to the variability of the ongoing environmental processes. Although several studies have highlighted the effect of climate warming in affecting birds altitudinal responses, in the Alps, land abandonment and the consequential forest regrowth may have played a fundamental role. We applied the response curve shape method to investigate changes in the altitudinal distribution of breeding birds over a ten-year period in two different alpine areas (Central and Western Italian Alps) and we performed a log-linear analysis to depict the differential responses of species grouped according to their breeding habitat preferences. The patterns of change remarkably differed according to species ecological traits and between mountain areas. We did not highlight clear altitudinal changes in the Central Alps for any ecological groups, while in the Western Alps, woodland birds showed an expansion pattern and grassland birds suffered a retraction pattern. Since the two alpine areas did not suffer a significant temperature increase, but experienced different woodland cover dynamics, we believe that forest regrowth played a key role in shaping the different bird altitudinal responses between the two sites. Our findings illustrate the effect of ecological traits in shaping altitudinal changes and the role of local environmental factors in affecting spatial variation. Particularly, we strongly suggest considering woodland cover expansion as a key driver of bird altitudinal changes in alpine areas. Highlights • Birds'altitudinal responses change according to breeding habitat preferences. • Altitudinal patterns of change differ between mountain areas. • Differences in woodland cover dynamics lead to different bird's altitudinal responses. • Forest recolonization play a fundamental role in shaping birds' altitudinal changes in the Alps. [ABSTRACT FROM AUTHOR]

Abstract: Aims: Phylogenetic niche conservatism (PNC) predicts that closely related species will have similar distributions along major environmental gradients, e.g. temperature. We test this theory by comparing the central tendencies of temperature for selected woody genera, and investigating whether these genera have a similar rank order (sequence) across continents and hemispheres. A strong correlation may indicate niche conservatism, as inherited temperature tolerance would best explain a positive correlation. Location: Peru (Andes) and Nepal (Himalaya). Methods: Elevation and temperature ranges for all species belonging to eight disjunct genera of woody plants were compiled. Central tendencies of congeneric species along the temperature gradient were established by means of reciprocal averaging and weighted average temperature. We correlated the rank order of genera from the Himalaya and Andes, and tested if the order in the Himalaya could predict the order in the Andes, using permutation procedure. Results: Most genera exhibit a bell‐shaped or curvilinear pattern with the maximum number of congeneric species in the centre of the temperature range, but some curvilinear responses and monotonic increases are found in Andes. The order of generic optima along the temperature gradient in each region is highly correlated (ρ > 0.81), as well as the size of the temperature range and minimum temperature limit (ρ > 0.90). Conclusion: The analyses verify the conjecture that the maximum number of congeneric species is found towards the centre of the temperature range of the genus. This may be caused by newly evolving species not dispersing very far from their ancestors and inherent temperature tolerances. Inherent temperature tolerance and covariates such as primary production and soil conditions are the main factors that may explain consistency of the rank order of disjunct genera along temperature gradients between continents and hemispheres. Hence temperature tolerances within a clade are conserved over time and space. [ABSTRACT FROM AUTHOR]

To evaluate the response to lime on cultivars of ricebean (Vigna umbellata), a field experiment was conducted during the two consecutive rabi seasons of 2010–2011 and 2011–2012 in the Nagaland foothills, India. The experiment used a split-plot design with four levels of lime (control, 0.2, 0.4 and 0.6 t ha− 1) in main plots and four ricebean cultivars (RBS-16, RBS-53, PRR-2, and RCRB-4) in sub-plots with three replicates. The results revealed that increasing levels of lime (in the furrow) from 0 to 0.6 t ha− 1 significantly increased growth, yield attributes and yield. The quality parameters of ricebean were also influenced significantly by the application of lime. Maximum gross return (INR 39,098 ha− 1), net return (INR 27,281 ha− 1), benefit:cost (B:C) ratio (2.29), production efficiency, and economic efficiency were also realized with the application of lime at 0.6 t ha− 1. Among the ricebean cultivars, RBS-53 produced significantly higher growth, yield attributes, grain yield, straw yield, biological yield, and harvest index. Similarly, yield and protein content were higher in RBS-53. Maximum gross return, net return, B:C ratio, production efficiency, and economic efficiency were observed for RBS-53.

An abnormal non-monotonic shape of production function (response of obtained yield to increasing rates of mineral nitrogen fertilizers) has been observed in experimental field trials. Often, the observed effect (an inflection point, or intermediate plateau or even local undershoot of the “yield-fertilization” curve) is treated as a test distortion and will be ignored or sorted out. This article presents the authors’ efforts to interpret and to explain similar phenomenon by means of investigating two mechanistic crop simulation models – AGROSIM and AGROTOOL. It is demonstrated that an imitation model can be used as a valuable tool of scientific research, allowing for the hypothesising of alternative understandings of non-trivial natural phenomena. [ABSTRACT FROM AUTHOR]

The paper deals with the model for a hierarchic multi-level medium. This model consists of the specifically coupled oscillators with power law interactions. We consider the periodic regimes appearing in the model when the uppermost structural level is driven by a harmonic force. To study these regimes as solutions of strongly nonlinear high-dimensional dynamical system, we improve the method of specific points (MSP) and verify the results via the Galerkin method and direct numerical treatment. This gives us the amplitude–frequency response curves characterizing the peculiarities of vibrations in the model. In particular, we revealed the shifting of resonant frequencies depending on the measure of nonlinearity. The deformations of backbone curves leading to jump phenomena are observed as well. [ABSTRACT FROM AUTHOR]

The presence of heavy metal e.g. cadmium in potable water is one of the major threats on our health. It should be detected and removed from potable water before consumption. The maximum permissible concentration of cadmium ion in drinking water lies in the range of 2-10 ppb. The consumption of excessive cadmium through potable water can lead to cancer, and can affect the organs like kidney and lungs severely. In this article, we report the development of a piezoelectric based sensor for the detection of cadmium ion in water. A functional layer of nanocomposite of single walled carbon nanotubes and beewax was deposited by spin coating technique onto 5 MHz AT-cut quartz crystal wafers and the shift in resonance due to physioadsorption of cadmium from water medium was recorded. We find a very stable linear response curve with the lowest detectable concentration of 5.2 ppb. The change in the morphology of the functional layer before and after adsorption of cadmium is studied using atomic force microscope and field emission scanning electron microscope. The presence of calcium ion in water medium affected the response curves of cadmium sensing. We found a systematic variation in sensitivity towards Cd ion due to the presence of Ca ion in water medium. [ABSTRACT FROM AUTHOR]

In order to achieve the algorithm diversification portability of the computer monitoring system in the liquid level control, the paper designed a computer monitoring system based on Matlab graphical user interface (GUI). The system uses Matlab's serial communication API, and uses the RS-485/RS-232 data communication interface to achieve data collection and controlling for the three-tank. Modbus RTU protocol is applied for communication to ensure the accuracy of data transmission. System software has a friendly interface, easy programming, simple operation and other features, users can implant the algorithm to run the system in a variety of modes. Experimental result shows that design of the computer monitoring system can quickly and accurately draw the level response curve, Flash animation can simulate real-time experimental progress based on Matlab GUI. [ABSTRACT FROM AUTHOR]

To assess the relationship between chlorophyll (Chl) fluorescence (CF) and photosynthetic pigments, soybean was grown under varying phosphorus (P) nutrition at ambient and elevated CO (EC). The EC stimulated, but P deficiency decreased plant height, node numbers, and leaf area concomitantly with the rates of stem elongation, node addition, and leaf area expansion. Under P deficiency, CF parameters and pigments declined except that carotenoids (Car) were relatively stable indicating its role in photoprotection. The CF parameters were strongly related with Chl concentration but not with Chl a/b or Car. However, total Chl/Car showed the strongest association with CF parameters such as quantum efficiency and yield of photosystem II. This relationship was not affected by CO treatment. The high correlation between CF and total Chl/Car underscores the significance of the quantification of both, Chl and Car concentrations, to understand the photochemistry and underlying processes of photoprotection and mechanisms of excess energy dissipation in a given environment. [ABSTRACT FROM AUTHOR]

Exploring the phytogeographical distribution of roadside flora in natural areas provides several original insights into plant dispersal. The roadside flora of the Irano–Turanian rangelands was studied in the northeast of Iran, along about 600 km of asphalt road. Sampling was performed in homogenous physiognomic-physiographic units along the altitudinal gradient from the plain to the mountainous areas. In a stratified random design, 38 sites on 12 asphalt roads were sampled, and 330 plant taxa of different chorotypes were identified. The altitudinal distribution of the chorotypes was examined fitting generalized linear models (GLM) and generalized additive models (GAM). The results showed that native uni-regional taxa (Irano–Turanian elements) were the dominant chorotype of the roadside habitats in the rangeland areas. The altitudinal response curve of multi-regional (bi-regional to quadri-regional) chorotypes reflected climatic conditions in their contributing phytochoria. Quadri-regional taxa, with an optimum of the Gaussian response curve at mid-altitudes, reflected a moderate climate. The proportion of endemic species (3.6%) was high compared to the pluri-regional (4.6%) and the cosmopolitan taxa (1.2%). While the pluri-regional taxa increased with altitude, cosmopolitan species decreased monotonically and were absent from the high altitudes. This study revealed the importance of the mid-altitude roadsides, both as a refuge for local endemic species and as a bed for local weeds and regional alien species. [ABSTRACT FROM AUTHOR]