Degradation of trifluralin in three Victorian soils —long-term field trials

1998 ◽  
Vol 38 (4) ◽  
pp. 363 ◽  
Author(s):  
P. K. Johnstone ◽  
A. V. Jolley ◽  
G. R. Code ◽  
M. R. Moerkerk ◽  
A. Corbett
Keyword(s):  
Field Trials ◽  
Application Rate ◽  
Influential Factors ◽  
Maximum Temperature ◽  
Weather Factors ◽  
Measured Concentration ◽  
Average Maximum ◽  
Average Maximum Temperature ◽  
Residue Concentration

Summary. The persistence of trifluralin was investigated at 3 sites in southern Australia over 8 years. Persistence varied from year-to-year, with the highest persistence being recorded at all sites in the dry year of 1984. Trifluralin persistence (expressed as a percentage of the initial measured concentration) 1 year after application was lowest at Rutherglen (7–22%), followed by Dooen (7–26%) and Walpeup (13–120%). Trifluralin degradation at Walpeup in 1984 was negligible. The resultant high residue concentrations would have posed a threat to subsequent crops. However, 1 year later after the subsequent fallow, the residue concentration had dropped to more typical levels. Trifluralin did not accumulate after repeated application (either 1 or 2 years apart) at all 3 sites. It was found important to measure the amount of trifluralin in the soil immediately after application because the trifluralin concentration could not be assumed from the rate. Soil concentrations immediately after application ranged from 32 to 138% of that expected from the nominal application rate. Therefore, measuring initial concentrations when comparisons were to be made between treatments, years and sites, was essential. In addition to studies of 1 year persistence, trifluralin concentration was also measured 2 years after application at Walpeup and Dooen. There was evidence to suggest that the rate of degradation over the same 1 year period, was different for a recent application when compared with weathered trifluralin residues from a previous application. Correlations between persistence and various weather factors indicated that the most influential factors were those that occurred in the first 60 days after application. These included total rainfall, effective rainfall (rainfall minus evaporation) and average maximum temperature.

scholarly journals A Consistent Methodology to Evaluate Temperature and Heat Wave Future Projections for Cities: A Case Study for Lisbon

2020 ◽  
Vol 10 (3) ◽  
pp. 1149 ◽  
Author(s):  
Alfredo Rocha ◽  
Susana C. Pereira ◽  
Carolina Viceto ◽  
Rui Silva ◽  
Jorge Neto ◽  
...  
Keyword(s):  
Climate Change ◽  
Heat Wave ◽  
Heat Waves ◽  
Maximum Temperature ◽  
Present Climate ◽  
Average Maximum ◽  
Recent Climate ◽  
Average Maximum Temperature ◽  
Accumulated Temperature

Heat waves are large-scale atmospheric phenomena that may cause heat stress in ecosystems and socio-economic activities. In cities, morbidity and mortality may increase during a heat wave, overloading health and emergency services. In the face of climate change and associated warming, cities need to adapt and mitigate the effects of heat waves. This study suggests a new method to evaluate heat waves’ impacts on cities by considering some aspects of heat waves that are not usually considered in other similar studies. The method devises heat wave quantities that are easy to calculate; it is relevant to assessing their impacts and permits the development of adaptation measures. This study applies the suggested method to quantify various aspects of heat waves in Lisbon for future climate projections considering future mid-term (2046–2065) and long-term (2081–2100) climates under the RCP8.5 greenhouse emission scenario. This is achieved through the analysis of various regional climate simulations performed with the WRF model and an ensemble of EURO-CORDEX models. This allows an estimation of uncertainty and confidence of the projections. To evaluate the climate change properties of heat waves, statistics for future climates are compared to those for a reference recent climate. Simulated temperatures are first bias corrected to minimize the model systematic errors relative to observations. The temperature for mid and long-term futures is expected to increase relative to the present by 1.6 °C and 3.6 °C, respectively, with late summer months registering the highest increases. The number of heat wave days per year will increase on average from 10, in the present climate, to 38 and 63 in mid and long-term climates, respectively. Heat wave duration, intensity, average maximum temperature, and accumulated temperature during a heat wave will also increase. Heat waves account for an annual average of accumulated temperature of 358 °C·day in the present climate, while in the mid and long-term, future climates account for 1270 °C·day and 2078 °C·day, respectively. The largest increases are expected to occur from July to October. Extreme intensity and long-duration heat waves with an average maximum temperature of more than 40 °C are expected to occur in the future climates.

scholarly journals Exploring the Sensitivity of Subtropical Stand Aboveground Productivity to Local and Regional Climate Signals in South China

Forests ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 71 ◽  
Author(s):  
Hua Zhou ◽  
Yang Luo ◽  
Guang Zhou ◽  
Jian Yu ◽  
Sher Shah ◽  
...  
Keyword(s):  
Regional Climate ◽  
Mixed Forest ◽  
Single Species ◽  
Forest Productivity ◽  
Maximum Temperature ◽  
Forest Types ◽  
Monthly Average ◽  
Aboveground Productivity ◽  
Average Maximum ◽  
Average Maximum Temperature

Subtropical forest productivity is significantly affected by both natural disturbances (local and regional climate changes) and anthropogenic activities (harvesting and planting). Monthly measures of forest aboveground productivity from natural forests (primary and secondary forests) and plantations (mixed and single-species forests) were developed to explore the sensitivity of subtropical mountain productivity to the fluctuating characteristics of climate change in South China, spanning the 35-year period from 1981 to 2015. Statistical analysis showed that climate regulation differed across different forest types. The monthly average maximum temperature, precipitation, and streamflow were positively correlated with primary and mixed-forest aboveground net primary productivity (ANPP) and its components: Wood productivity (WP) and canopy productivity (CP). However, the monthly average maximum temperature, precipitation, and streamflow were negatively correlated with secondary and single-species forest ANPP and its components. The number of dry days and minimum temperature were positively associated with secondary and single-species forest productivity, but inversely associated with primary and mixed forest productivity. The multivariate ENSO (EI Niño-Southern Oscillation) index (MEI), computed based on sea level pressure, surface temperature, surface air temperature, and cloudiness over the tropical Pacific Ocean, was significantly correlated with local monthly maximum and minimum temperatures (Tmax and Tmin), precipitation (PRE), streamflow (FLO), and the number of dry days (DD), as well as the monthly means of primary and mixed forest aboveground productivity. In particular, the mean maximum temperature increased by 2.5, 0.9, 6.5, and 0.9 °C, and the total forest aboveground productivity decreased by an average of 5.7%, 3.0%, 2.4%, and 7.8% in response to the increased extreme high temperatures and drought events during the 1986/1988, 1997/1998, 2006/2007, and 2009/2010 EI Niño periods, respectively. Subsequently, the total aboveground productivity values increased by an average of 1.1%, 3.0%, 0.3%, and 8.6% because of lagged effects after the wet La Niña periods. The main conclusions of this study demonstrated that the influence of local and regional climatic fluctuations on subtropical forest productivity significantly differed across different forests, and community position and plant diversity differences among different forest types may prevent the uniform response of subtropical mountain aboveground productivity to regional climate anomalies. Therefore, these findings may be useful for forecasting climate-induced variation in forest aboveground productivity as well as for selecting tree species for planting in reforestation practices.

The safety of dental extractions in patients with hematologic malignancies.

1989 ◽  
Vol 7 (6) ◽  
pp. 798-802 ◽  
Author(s):  
S K Williford ◽  
P L Salisbury ◽  
J E Peacock ◽  
J M Cruz ◽  
B L Powell ◽  
...  
Keyword(s):  
Wound Healing ◽  
Myeloproliferative Disorders ◽  
Hematologic Malignancies ◽  
Maximum Temperature ◽  
Average Maximum ◽  
Average Maximum Temperature ◽  
Sources Of Infection ◽  
The Mean ◽  
Risk For Bleeding ◽  
Dental Infections

Dental disorders have been recognized as major sources of infection in patients with hematologic malignancies (HM). Management of severe dental infections usually includes dental extractions (DE), but the safety of extractions in patients with HM who are at risk for bleeding, sepsis, and poor wound healing has not been well established. In conjunction with an aggressive program of dental care, 142 DE were performed in 26 patients with acute leukemia, myelodysplastic syndromes, and myeloproliferative disorders. Granulocytopenia (less than 1,000 granulocytes/microL) was present during or within ten days following surgery in 14 patients. In these 14 patients (101 DE), the mean granulocyte count was less than 450/microL, with a median duration of granulocytopenia following surgery of 32 days (range, four to 169 days). Thrombocytopenia (less than 100,000 platelets/microL) occurred during or within two days following surgery in 13 patients (80 DE), with a mean platelet count of 63,500/microL. Transfusions were given for platelet counts less than 50,000/microL. All DE were performed without significant complications. Bleeding was minor to moderate and easily controlled with local measures; no patient required transfusion due to hemorrhage. Average maximum temperature 24 hours after DE was 37.7 degrees C. No episodes of bacteremia were documented within ten days of DE. Minor delay in wound healing was observed in two patients. We conclude that DE can be safely performed in patients with HM in combination with aggressive supportive care.

Influence of season and environment on fertility of goats in a hot-arid environment

2002 ◽  
Vol 138 (1) ◽  
pp. 97-102 ◽  
Author(s):  
M. MELLADO ◽  
C. A. MEZA-HERRERA
Keyword(s):  
Arid Environment ◽  
Conception Rate ◽  
Maximum Temperature ◽  
Mean Annual Precipitation ◽  
Ambient Temperatures ◽  
Northern Mexico ◽  
Average Maximum ◽  
Average Maximum Temperature ◽  
Maximum Temperatures ◽  
Breeding Efficiency

Conception rate and prolificacy of dairy and crossbred goats under intensive conditions in an arid environment of northern Mexico (26° 06′ 15′′ N; maximum temperature throughout the year 12–42 °C, mean annual precipitation 186 mm, and RH <40% year-round) were examined with respect to season of mating, ambient temperature and rainfall at mating. The database contained 4194 natural services. Conception of goats inseminated with average maximum ambient temperatures >34 °C was significantly higher (P<0·01) than conception of goats inseminated when the average maximum temperature 3 days before breeding was <34 °C. The warmest season favoured conception rate (70% in spring; P<0·01) as compared to cooler seasons (62% and 64% for summer and autumn, respectively). Conception rate of goats bred when rain was present was 14 percentage points lower (P<0·01) compared to mating with no rain. When maximum temperatures on the day of mating were >34 °C, cooler temperatures 1 to 3 days before or after the day of mating were associated with a significant increase in the number of kids born. When the maximum temperature at mating was >36 °C, prolificacy for goats exposed to higher or lower temperatures 1 day before mating was 1·56 and 1·65, respectively (P<0·05). Similarly, when the maximum temperature at mating was 34–36 °C, prolificacy was higher for goats exposed to cooler temperatures as compared to warmer temperatures 1 day (1·64 v. 1·49; P<0·01) or 3 days (1·63 v. 1·48; P<0·01) after mating, with respect to the temperature on the day of mating. Conclusions were that conception rate was not compromised in non-lactating Alpine, Toggenburg, Granadino and Nubian goats subjected to high environmental temperature in an arid region, but the occurrence of rain at mating depressed breeding efficiency of these animals. Additionally, an increment in litter size is expected with cooler temperatures before or after hot days at time of mating.

Research on Heat Transfer and Environmental Impact of Horizontal Ground Heat Exchangers in Multi-Grooves

2012 ◽  
Vol 516-517 ◽  
pp. 395-400
Author(s):  
Zhong Yi Yu ◽  
Yan Hua Chen ◽  
Min Rui Zhou ◽  
Jian Ping Lei
Keyword(s):  
Heat Transfer ◽  
Heat Exchangers ◽  
Temperature Drop ◽  
Heat Extraction ◽  
Maximum Temperature ◽  
Pump System ◽  
Heat Pump System ◽  
Ground Heat Exchangers ◽  
Average Maximum ◽  
Average Maximum Temperature

This paper progresses to dynamically simulate and study the heat transfer process of horizontal ground heat exchangers in the multi-grooves by the use of numerical simulation based on the layout and heat extraction or rejection conditions of horizontal ground heat exchangers under the artificial lake. Effect of buried pipe type and groove spacing on the heat exchanger process is analyzed in detail. The influence of annual average water temperature change on the surrounding environment is evaluated with the introduction of parameters including summer weekly average maximum temperature rise and winter weekly average maximum temperature drop, in which can take the technical supports for the design of horizontal ground source heat pump system.

scholarly journals THE ANALYSIS OF SOIL TEMPERATURES IN DIFFERENT DEPTHS USING SPEARMAN’S RHO AND MANN-KENDALL CORRELATION TESTS: THE CASE STUDY OF NIGDE CENTER IN TURKEY

2020 ◽  
Vol 7 (5) ◽  
pp. 38-55
Author(s):  
M. Cüneyt Bagdatlı ◽  
Yiğitcan Ballı
Keyword(s):  
Soil Temperature ◽  
Soil Depth ◽  
Research Result ◽  
Significant Trend ◽  
Maximum Temperature ◽  
Average Maximum ◽  
Soil Temperatures ◽  
Average Maximum Temperature ◽  
Maximum Temperatures ◽  
Kendall Correlation

This research was conducted to determine soil temperatures in different soil depths in located Turkey’s Anatolia Region in Center of Nigde Province. In the study, the maximum, minimum and average soil temperature values of 10 cm, 50 cm and 100 cm depths observed between 1970-2019 were examined. All soil temperature data were evaluated monthly within the scope of the study. In the study, Mann-Kendall, Sperman's Rho correlation test and Sen's slope method were used.  According to the research result; The average of maximum soil temperatures in 10 cm depth was calculated as 6,8 0C in winter months and 20,7 0C in spring months. The average minimum soil temperature was calculated as 0,3 0C in winter and 5,0 0C in spring Months in long periods Generally, it was observed that there was an increasingly significant trend at maximum temperatures of 10 cm depth. According to the Mann-Kendal facility, a significant increase trend was observed in minimum soil temperatures in spring, winter and Summer months except for the months of autumn. Considering the average maximum temperature values in 50 cm; It was calculated as 6,6 °C in winter and 13,6 °C in spring months. The minimum soil temperature average was calculated as 3,5 0C in winter and 8,3 0C in spring months in long period (50 year, 600 months). In general, it was observed that there was an increasingly significant trend at maximum temperatures of 50 cm soil depth. According to Mann-Kendall and Sperman Rho test, a significant increase trend was observed in minimum soil temperatures in all seasons except for autumn months. According to the average maximum temperature values in 100 cm depth; It was calculated as 9,2 0C in winter and 11,5 0C in spring. The minimum soil temperature average was calculated as 7,1 0C in winter and 8.7 0C in spring months. It has been observed that there is a significant increase trend in the increasing of maximum and minimum soil temperatures of 100 cm soil depth.

scholarly journals ESTIMACIÓN DE LA PRODUCTIVIDAD PRIMARIA DURANTE OTOÑO-INVIERNO EN LA BAHÍA DE LA PAZ, B.C.S., MÉXICO

2008 ◽  
Vol 23 (1-2) ◽  
pp. 45
Author(s):  
G. Verdugo-Díaz ◽  
M. O. Albáñez-Lucero ◽  
R. Cervantes Duarte
Keyword(s):  
Chlorophyll A ◽  
Primary Productivity ◽  
El Niño ◽  
Gulf Of California ◽  
El Nino ◽  
Cold Season ◽  
Maximum Temperature ◽  
La Paz ◽  
Average Maximum ◽  
Average Maximum Temperature

Se analizó la variabilidad de la productividad primaria en Bahía de La Paz, durante noviembre de 1997 y 2000, enero de 1998 y febrero de 2001. Se identificó Agua del Golfo de California en mayor proporción; Agua Superficial Ecuatorial y Agua Subsuperficial Subtropical. En noviembre de 1997 se registró el valor promedio máximo de temperatura (~27.62 °C) y en febrero el valor mínimo (~19.16 °C). El índice de Simpson (Ö) indicó que durante noviembre de 1997 (~286.6 J m-3) la columna de agua presentó mayor estratificación, mientras que en noviembre de 1998 (~60.4 J m-3) y febrero de 2001 (~94.5 J m-3) se encontró mezclada. En noviembre de 1997 se registraron bajos valores de nitratos (~1.52 µM), nitritos (~0.04 µM) y clorofila a (~0.44 mg Cla m-3). En febrero de 2001 se registraron valores mayores de nitratos (~7.46 µM), nitritos (~0.76 µM) y clorofila a (~1.07 mg Cla m-3). La productividad primaria superficial e integrada presentaron sus promedios máximos en noviembre de 2000 (~5.09 mg C m-3 h-1 y 75.54. mg m-2 h-1) y mínimos en noviembre de 1997 (~2.93 mg C m-3 h-1 y ~55.29 mg m-2 h-1), respectivamente. De acuerdo a investigaciones anteriores, los valores reportados de productividad son característicos de la temporada fría de la bahía con excepción de noviembre de 1997, que presentó influencia de El Niño. Primary productivity stimation during autumm-winter in Bahía de La Paz, B.C.S., Mexico We analyzed the variability of primary productivity in Bahía de La Paz during November 1997 and 2000, January 1998 and February 2001. Water was identified in the Gulf of California in higher proportion; Surface Water and Water Subsuperficial Equatorial Subtropical. In November 1997 we saw the average maximum temperature (~ 27.62 ° C) in February and the lowest value (~ 19.16 ° C). The index of Simpson (Ö) indicated that during November 1997 (~ 286.6 J-3 m) column of water with greater stratification, while in November 1998 (~ 60.4 m J-3) and February 2001 (~ 94.5 J m-3) was mixed. In November 1997 there were low values of nitrate (~ 1.52 µM), nitrites (~ 0.04 µM) and chlorophyll a (Cla ~ 0.44 mg m-3). In February 2001, there were larger values of nitrate (~ 7.46 µM), nitrites (~ 0.76 µM) and chlorophyll a (Cla ~ 1.07 mg m-3). The primary productivity and integrated surface presented their highest averages in November 2000 (C ~ 5.09 mg m-3 h-1 and 75.54. mg m-2 h-1) and minimum in November 1997 (C ~ 2.93 mg m-3 h-1 and ~ 55.29 mg m-2 h-1), respectively. According to previous research, reported productivity values are characteristic of the cold season of the bay with exception of November 1997, which showed influence of El Niño.

The influence of temperature on energy budget variables, body size, and seasonal occurrence of the isopod Idotea baltica (Pallas)

1980 ◽  
Vol 58 (11) ◽  
pp. 1992-1996 ◽  
Author(s):  
Kim W. Strong ◽  
Graham R. Daborn
Keyword(s):  
Body Size ◽  
Seasonal Occurrence ◽  
Maximum Temperature ◽  
Idotea Baltica ◽  
Average Maximum ◽  
Influence Of Temperature On ◽  
Freshwater Crustacean ◽  
Average Maximum Temperature ◽  
Lower Temperature ◽  
Two Populations

Effects of temperature on ingestion (C) and metabolic (R) rates in Idotea baltica are examined to explain differences in maximum body size, longevity, and seasonal occurrence in two populations occupying habitats differing by 2–4 °C in average maximum temperature. Results illustrate that C and R are differentially affected by temperature such that the value C – R varies considerably with both body size and temperature. These data indicate that small isopods (< 20 mg) would grow most rapidly at the highest temperature studied (14 °C), whereas larger animals have maximum C – R values, and presumably grow most rapidly, at cooler temperatures (ca. 9 °C). The pattern explains why the population at the lower temperature lives twice as long, grows to much larger size, and apparently leaves the intertidal zone for a longer period than do those living in the similar warmer habitat. The results are discussed in relation to phenomena noted in other marine and freshwater crustacean populations.

scholarly journals Salmonella enterica Serovar Typhimurium and Escherichia coli Contamination of Root and Leaf Vegetables Grown in Soils with Incorporated Bovine Manure

2002 ◽  
Vol 68 (6) ◽  
pp. 2737-2744 ◽  
Author(s):  
Erin E. Natvig ◽  
Steven C. Ingham ◽  
Barbara H. Ingham ◽  
Leslie R. Cooperband ◽  
Teryl R. Roper
Keyword(s):  
Escherichia Coli ◽  
Salmonella Enterica ◽  
Maximum Temperature ◽  
Manure Application ◽  
E Coli ◽  
Daily Average ◽  
Fertilized Soil ◽  
Average Maximum ◽  
Serovar Typhimurium ◽  
Average Maximum Temperature

ABSTRACT Bovine manure, with or without added Salmonella enterica serovar Typhimurium (three strains), was incorporated into silty clay loam (SCL) and loamy sand (LS) soil beds (53- by 114-cm surface area, 17.5 cm deep) and maintained in two controlled-environment chambers. The S. enterica serovar Typhimurium inoculum was 4 to 5 log CFU/g in manure-fertilized soil. The conditions in the two environmental chambers, each containing inoculated and uninoculated beds of manure-fertilized soil, simulated daily average Madison, Wis., weather conditions (hourly temperatures, rainfall, daylight, and humidity) for a 1 March or a 1 June manure application and subsequent vegetable growing seasons ending 9 August or 28 September, respectively. Core soil samples were taken biweekly from both inoculated and uninoculated soil beds in each chamber. Radishes, arugula, and carrots were planted in soil beds, thinned, and harvested. Soils, thinned vegetables, and harvested vegetables were analyzed for S. enterica serovar Typhimurium and Escherichia coli (indigenous in manure). After the 1 March manure application, S. enterica serovar Typhimurium was detected at low levels in both soils on 31 May, but not on vegetables planted 1 May and harvested 12 July from either soil. After the 1 June manure application, S. enterica serovar Typhimurium was detected in SCL soil on 7 September and on radishes and arugula planted in SCL soil on 15 August and harvested on 27 September. In LS soil, S. enterica serovar Typhimurium died at a similar rate (P ≥ 0.05) after the 1 June manure application and was less often detected on arugula and radishes harvested from this soil compared to the SCL soil. Pathogen levels on vegetables were decreased by washing. Manure application in cool (daily average maximum temperature of <10°C) spring conditions is recommended to ensure that harvested vegetables are not contaminated with S. enterica serovar Typhimurium. Manure application under warmer (daily average maximum temperature >20°C) summer conditions is not recommended when vegetable planting is done between the time of manure application and late summer. A late fall manure application will not increase the risk of contaminating vegetables planted the next spring, since further experiments showed that repeated freeze-thaw cycles were detrimental to the survival of S. enterica serovar Typhimurium and E. coli in manure-fertilized soil. The number of indigenous E. coli in soil was never significantly lower (P < 0.05) than that of S. enterica serovar Typhimurium, suggesting its usefulness as an indicator organism for evaluating the risk of vegetable contamination with manure-borne S. enterica serovar Typhimurium.

scholarly journals Low soil moisture predisposes field-grown chickpea plants to dry root rot disease: evidence from simulation modeling and correlation analysis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ranjita Sinha ◽  
Vadivelmurugan Irulappan ◽  
Basavanagouda S. Patil ◽  
Puli Chandra Obul Reddy ◽  
Venkategowda Ramegowda ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Root Rot ◽  
Disease Incidence ◽  
Maximum Temperature ◽  
Validation Dataset ◽  
Water Deficit Stress ◽  
Weather Factors ◽  
Rhizoctonia Bataticola ◽  
Average Maximum ◽  
The Impact

AbstractRhizoctonia bataticola causes dry root rot (DRR), a devastating disease in chickpea (Cicer arietinum). DRR incidence increases under water deficit stress and high temperature. However, the roles of other edaphic and environmental factors remain unclear. Here, we performed an artificial neural network (ANN)-based prediction of DRR incidence considering DRR incidence data from previous reports and weather factors. ANN-based prediction using the backpropagation algorithm showed that the combination of total rainfall from November to January of the chickpea-growing season and average maximum temperature of the months October and November is crucial in determining DRR occurrence in chickpea fields. The prediction accuracy of DRR incidence was 84.6% with the validation dataset. Field trials at seven different locations in India with combination of low soil moisture and pathogen stress treatments confirmed the impact of low soil moisture on DRR incidence under different agroclimatic zones and helped in determining the correlation of soil factors with DRR incidence. Soil phosphorus, potassium, organic carbon, and clay content were positively correlated with DRR incidence, while soil silt content was negatively correlated. Our results establish the role of edaphic and other weather factors in chickpea DRR disease incidence. Our ANN-based model will allow the location-specific prediction of DRR incidence, enabling efficient decision-making in chickpea cultivation to minimize yield loss.

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