scholarly journals Off-site movement of quinclorac from rice fields

2021 ◽  
Author(s):  
Francesco Vidotto ◽  
Silvia Fogliatto ◽  
Lorenzo Carmagnola ◽  
Fernando De Palo ◽  
Marco Milan
Keyword(s):  
Management Practices ◽  
Water Discharge ◽  
Field Studies ◽  
Paddy Fields ◽  
Irrigation District ◽  
Public And Private ◽  
Paddy Water ◽  
Holding Period ◽  
Growing Seasons ◽  
Public And Private Stakeholders

Highlights - Quinclorac persistence in paddy water is affected by its residues in entering waters. - Entering waters often contain quinclorac residues. - A water holding period of at least 10 days may limit the offsite movement of quinclorac residues from paddy fields. Abstract The off-site movement of quinclorac from rice paddies was studied in a district and field study during the 2014 and 2015 growing seasons. Quinclorac residues were monitored on in-field surface waters, and out-field water entering and leaving an irrigation district. The behavior of quinclorac residues in paddy water pointed out that the movement of herbicides from interconnected paddies is not negligible. This phenomenon was particularly evident in the days following the re-flooding of paddies after spraying. The water entering the uphill paddy fields have partially flushed quinclorac residues in the downhill paddy fields. Both the district and the field studies, showed the continuous presence of quinclorac residues in inlet waters. Even because of the continuous uploading of residues from inlet waters, traces of quinclorac in paddy water were detected up to 70 DAT. The presence of quinclorac in inlet water could be related to phenomena of drainage and drift during herbicide application in the paddies located upstream. The analysis carried out on waters leaving the district showed the presence of quinclorac residues in all the outlet floodgates, particularly from the end of May and late August. The results of this study suggest that appropriate management practices adopted at field scale may be required to lower the water contamination at irrigation district level. Considering that the highest losses of quinclorac occurred during the first 10-15 days after its application, to prevent these losses could be helpful avoiding water discharge from the treated fields for at least this period of time. In addition, a deep effort must be laid upon education and training of farmers on these environmental thematic throughout specific initiatives organized by public and private stakeholders.

scholarly journals Discharge and sediment loads of two streams in the mid-hills of central Nepal

1970 ◽  
Vol 2 (3) ◽  
pp. 51-54 ◽  
Author(s):  
Roshan M Bajracharya ◽  
Subodh Sharma ◽  
Roberto Clemente
Keyword(s):  
Land Use ◽  
Stream Flow ◽  
Management Practices ◽  
Nutrient Loading ◽  
Water Discharge ◽  
Sediment Concentration ◽  
Sediment Yields ◽  
Growing Seasons ◽  
Sediment Loads ◽  
Land Use And Management

Stream flow, nutrient loading, and sediment yield closely reflect land use and management practices in relation to growing seasons in mid-hill watersheds of the central Himalaya. A preliminary study was conducted to determine approximate total water discharge and sediment yields from the Galaundi and Pokhare catchments. Mean discharge and sediment loads during the 2002 rainy season were 2.1 m3?s-1 and 0.9 kg?s-1 for Galaundi Khola and 0.45 m3 s-1 and 0.28 kg?s-1 for Pokhare Khola. Estimates of total annual discharge of water and sediment were, respectively, 27.8 million m3 and 11,400 t (Galaundi) and 6.4 million m3 and 3,500 t (Pokhare). These corresponded to about 71.6% and 60.4% of total rain volumes and soil loss rates of 5.18 t?ha-1 and 5.83 t?ha-1 for Galaundi and Pokhare sub-watersheds, respectively. Good correlations were observed for stream discharge vs. sediment concentration (R2 = 0.83 and 0.94 respectively) and rainfall amount vs. discharge (R2 = 0.94 and 0.96 respectively) for both streams. Key words: stream flow, sediment concentration, land use, pre-monsoon, sub-watershed Himalayan Journal of Sciences 2(3): 51-54, 2004

scholarly journals Oxadiazon Dissipation in Water and Topsoil in Flooded and Dry-Seeded Rice Fields

Agronomy ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 557 ◽  
Author(s):  
Marco Milan ◽  
Aldo Ferrero ◽  
Silvia Fogliatto ◽  
Serenella Piano ◽  
Michéle Negre ◽  
...  
Keyword(s):  
Residence Time ◽  
Half Life ◽  
Rice Fields ◽  
Water Bodies ◽  
Paddy Fields ◽  
North West ◽  
Paddy Water ◽  
Growing Seasons ◽  
Over Time

The aim of the present study was to assess the behavior of oxadiazon in topsoil and waters of paddy fields cultivated according to the two rice seeding systems: conventional water seeding (CON) and dry seeding (DRY). The study was carried out from 2012 to 2013 in Vercelli, north-west of Italy, the most important rice growing area of Europe. Variations in oxadiazon concentrations were studied over time in topsoil, paddy water, inlet water and outlet water. Over the two years, the estimated oxadiazon topsoil half-life was 3.27 days, without significant differences between systems and years. Oxadiazon dissipation in the paddy water was rapid during the first week, but less pronounced late in the season. Residues of oxadiazon were frequently detected in inlet waters. Transfer of oxadiazon residues in outlet waters occurred over all the growing seasons, with important peaks in the first weeks after the treatment. A possible way to reduce the transfer of oxadiazon to water bodies could be increasing the residence time of the herbicide in the paddy fields during the first 7–10 days after spraying, avoiding the release of water from them.

Economic incentives encourage farmers to improve water management in California

Water Policy ◽  
2006 ◽  
Vol 8 (3) ◽  
pp. 269-285 ◽  
Author(s):  
Dennis Wichelns
Keyword(s):  
Water Management ◽  
Program Implementation ◽  
Management Practices ◽  
Economic Incentives ◽  
Irrigation District ◽  
Drain Water ◽  
Scarce Resources ◽  
San Joaquin River ◽  
Water Volumes ◽  
Individual Use

Economic incentives are used in many situations to motivate improvements in the use of scarce resources. In some areas, implementing appropriate incentives is made challenging by the nature of existing institutions or the inability to assign property rights and measure individual use of key resources. Higher prices for irrigation water can motivate wiser use of water in regions where the opportunity cost of water is rising, due to increasing municipal, industrial and environmental demands. This paper describes how an increasing block-rate pricing structure was designed and implemented in an irrigation district in central California. The goals of the program were to improve water management practices and reduce the volume of subsurface drain water discharged into the San Joaquin River. Results describing reductions in average irrigation depths and drain water volumes, collected throughout the 1990s, demonstrate the potential for achieving resource management goals with economic incentives that motivate changes in farm-level management practices. Complementary incentive programs and issues regarding program implementation and the sustainability of drain water reduction efforts in an arid region also are discussed.

scholarly journals High-Resolution Monitoring and Assessment of Evapotranspiration and Gross Primary Production Using Remote Sensing in a Typical Arid Region

Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 396
Author(s):  
Junxia Yan ◽  
Yanfei Ma ◽  
Dongyun Zhang ◽  
Zechen Li ◽  
Weike Zhang ◽  
...  
Keyword(s):  
Remote Sensing ◽  
High Resolution ◽  
Land Surface ◽  
Arid Region ◽  
Management Practices ◽  
Gross Primary Production ◽  
Irrigation District ◽  
Heihe River ◽  
Freshwater Resource ◽  
Oasis Area

Land surface evapotranspiration (ET) and gross primary productivity (GPP) are critical components in terrestrial ecosystems with water and carbon cycles. Large-scale, high-resolution, and accurately quantified ET and GPP values are important fundamental data for freshwater resource management and help in understanding terrestrial carbon and water cycles in an arid region. In this study, the revised surface energy balance system (SEBS) model and MOD17 GPP algorithm were used to estimate daily ET and GPP at 100 m resolution based on multi-source satellite remote sensing data to obtain surface biophysical parameters and meteorological forcing data as input variables for the model in the midstream oasis area of the Heihe River Basin (HRB) from 2010 to 2016. Then, we further calculated the ecosystem water-use efficiency (WUE). We validated the daily ET, GPP, and WUE from ground observations at a crop oasis station and conducted spatial intercomparisons of monthly and annual ET, GPP, and WUE at the irrigation district and cropland oasis scales. The site-level evaluation results show that ET and GPP had better performance than WUE at the daily time scale. Specifically, the deviations in the daily ET, GPP, and WUE data compared with ground observations were small, with a root mean square error (RMSE) and mean absolute percent error (MAPE) of 0.75 mm/day and 26.59%, 1.13 gC/m2 and 36.62%, and 0.50 gC/kgH2O and 39.83%, respectively. The regional annual ET, GPP, and WUE varied from 300 to 700 mm, 200 to 650 gC/m2, and 0.5 to 1.0 gC/kgH2O, respectively, over the entire irrigation oasis area. It was found that annual ET and GPP were greater than 550 mm and 500 gC/m2, and annual oasis cropland WUE had strong invariability and was maintained at approximately 0.85 gC/kgH2O. The spatial intercomparisons from 2010 to 2016 revealed that ET had similar spatial patterns to GPP due to tightly coupled carbon and water fluxes. However, the WUE spatiotemporal patterns were slightly different from both ET and GPP, particularly in the early and late growing seasons for the oasis area. Our results demonstrate that spatial full coverage and reasonably fine spatiotemporal variation and variability could significantly improve our understanding of water-saving irrigation strategies and oasis agricultural water management practices in the face of water shortage issues.

scholarly journals Effect of Weed Management on the Parasitoid Community in Mediterranean Vineyards

Biology ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 7
Author(s):  
Gabriella Möller ◽  
Tamar Keasar ◽  
Idan Shapira ◽  
Daniella Möller ◽  
Marco Ferrante ◽  
...  
Keyword(s):  
Cover Crops ◽  
Weed Management ◽  
Soil Conservation ◽  
Management Practices ◽  
Ground Cover ◽  
Parasitoid Species ◽  
Parasitoid Community ◽  
Growing Seasons ◽  
Conservation Biocontrol ◽  
Suction Sampling

Enriching agroecosystems with non-crop vegetation is a popular strategy for conservation biocontrol. In vineyards, the effects of specific seeded or planted cover crops on natural enemies are well-studied, whereas conserving spontaneously developing weeds received less attention. We compared parasitoid communities between matched pairs of vineyard plots in northern Israel, differing in weed management practices: “herbicide”, repeated herbicide applications vs. “ground cover”, maintaining resident weeds and trimming them when needed. Using suction sampling, we assessed the parasitoids’ abundance, richness, and composition during three grape-growing seasons. Ground cover plots had greater parasitoid abundances and cumulative species richness than herbicide-treated plots, possibly because of their higher vegetation cover and richness. Dominant parasitoid species varied in their magnitude and direction of response to weed management. Their responses seem to combine tracking of host distributions with attraction to additional vegetation-provided resources. Parasitoid community composition was mildly yet significantly influenced by weed management, while season, year, and habitat (weeds vs. vine) had stronger effects. Vineyard weeds thus support local biocontrol agents and provide additional previously demonstrated benefits (e.g., soil conservation, lower agrochemical exposure) but might also attract some crop pests. When the benefits outweigh this risk, weed conservation seems a promising step towards more sustainable agricultural management.

scholarly journals The Effect of Grapevine Age (Vitis vinifera L. cv. Zinfandel) on Phenology and Gas Exchange Parameters over Consecutive Growing Seasons

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 311
Author(s):  
Vegas Riffle ◽  
Nathaniel Palmer ◽  
L. Federico Casassa ◽  
Jean Catherine Dodson Peterson
Keyword(s):  
Gas Exchange ◽  
Water Potential ◽  
Leaf Water Potential ◽  
Management Practices ◽  
Leaf Water ◽  
Sugar Accumulation ◽  
Gas Exchange Parameters ◽  
Growing Season Length ◽  
Growing Seasons ◽  
Exchange Parameters

Unlike most crop industries, there is a strongly held belief within the wine industry that increased vine age correlates with quality. Considering this perception could be explained by vine physiological differences, the purpose of this study was to evaluate the effect of vine age on phenology and gas exchange parameters. An interplanted, dry farmed, Zinfandel vineyard block under consistent management practices in the Central Coast of California was evaluated over two consecutive growing seasons. Treatments included Young vines (5 to 12 years old), Control (representative proportion of young to old vines in the block), and Old vines (40 to 60 years old). Phenology, leaf water potential, and gas exchange parameters were tracked. Results indicated a difference in phenological progression after berry set between Young and Old vines. Young vines progressed more slowly during berry formation and more rapidly during berry ripening, resulting in Young vines being harvested before Old vines due to variation in the timing of sugar accumulation. No differences in leaf water potential were found. Young vines had higher mid-day stomatal conductance and tended to have higher mid-day photosynthetic rates. The results of this study suggest vine age is a factor in phenological timing and growing season length.

scholarly journals Prediction of leaching and groundwater contamination by pesticides

2006 ◽  
Vol 78 (5) ◽  
pp. 1081-1090 ◽  
Author(s):  
Werner Kördel ◽  
Michael Klein
Keyword(s):  
Maximum Concentration ◽  
Management Practices ◽  
Preferential Flow ◽  
Soil Depth ◽  
Sandy Soils ◽  
Field Studies ◽  
Macropore Flow ◽  
Eu Directive ◽  
Present Information ◽  
Silty Soils

Herein, we describe how pesticide leaching is assessed in Europe in order to fulfill EU Directive 91/414. The assessment schemes were developed to protect groundwater from unacceptable effects caused by pesticide use. They presently focus on chromatographic flow processes, which are dominant in sandy soils. Nevertheless, important regions in Europe are characterized by structured soils where transport through macropores is most relevant.Comparison of parallel field studies with isoproturon performed in sandy and silty soils showed that maximum concentration in the structured soil at a soil depth of 1 m may exceed respective concentrations in sandy soils by a factor of 60. Similar results were obtained by lysimeter studies using silty soil cores with maximum concentration of 40 μg/l at the soil bottom. These results demonstrate that preferential flow is more the rule than the exception in well-structured fine-textured soils, and pesticide losses via macropore flow may exceed losses via matrix transport considerably. All present information available for macropore flow suggest the need for greater regional assessments. Other recommendations include analysis of the influence of different soil management practices on the formation of macropores.

Biological invasions: are they dependent on disturbance?

1997 ◽  
Vol 5 (2) ◽  
pp. 131-144 ◽  
Author(s):  
J D Lozon ◽  
H J MacIsaac
Keyword(s):  
Exotic Species ◽  
Human Activities ◽  
Water Discharge ◽  
A Priori ◽  
Terrestrial Ecosystems ◽  
Field Studies ◽  
Soil Disturbance ◽  
Exotic Animals ◽  
Introduced Plants ◽  
Disturbed Habitats

We utilize literature surveys to examine the relationship between establishment of exotic species and human or natural disturbances of ecosystems. Of the 133 papers published in 10 ecological journals between 1993 and 1995, 63 reported on field studies involving 299 and 103 successful, nonredundant plant and animal introductions, respectively. Invasions of terrestrial ecosystems dominated (>>97%) the surveyed literature. Disturbance was associated with establishment of exotic species in 56% of these studies, though its importance differed among papers describing plants (68%) and animals (28%). Plants species (86%) were significantly more dependent on disturbance for establishment than were animals (12%). However, animals and plants that were dependent on disturbance for establishment were almost equally dependent (58 versus 68%) on it for range expansion. In a second survey, 402 plant and 103 animal taxa were identified that explicitly linked establishment of exotic species to disturbance. Human activities were attributed with establishment of species in 97 and 57% of these cases, respectively. Common mechanisms associated with establishment of exotic animals included ballast water discharge, intentional releases, and residential development. Establishment of exotic plants was associated with animal activities (e.g., grazing, seed introduction), soil disturbance, forestry, fire, agriculture, and human activities. In contrast to invasions theory, our survey indicates that the association between establishment and spread of exotic species and disturbance ought not be assumed a priori. Some animals repeatedly invade new habitats once geographic barriers are circumvented, indicating that communities may be more receptive to exotic species than previously acknowledged. By contrast, introduced plants established most often in disturbed habitats.

Evaluating the performance of destination marketing systems (DMS): stakeholder perspective

2014 ◽  
Vol 32 (2) ◽  
pp. 208-231 ◽  
Author(s):  
Marianna Sigala
Keyword(s):  
Performance Evaluation ◽  
Destination Marketing ◽  
Collaborative Culture ◽  
Public And Private ◽  
Content Type ◽  
Stakeholder Perspective ◽  
Marketing Systems ◽  
Public And Private Stakeholders ◽  
Social Environmental ◽  
Nation Wide Survey

Purpose – Destination marketing systems (DMS) represent a vital inter-organisational information system (IOIS) for supporting the collaborative e-marketing strategies of tourism firms and the competitiveness of tourism destinations. However, many DMS have failed to deliver the expected outcomes, while the performance measurement of DMS has not been thoroughly investigated in the literature so far. The study synthesises research from the fields of DMS, IOIS and collaborative practices for investigating the perceptions of various tourism DMS stakeholders about the evaluation of DMS performance. The paper aims to discuss these issues. Design/methodology/approach – The study conducted a nation-wide survey for measuring the perceptions of various tourism DMS stakeholders in Greece about the importance of the roles that DMS should serve as well as the items that should be used for measuring the performance of these DMS’ roles. Findings – The findings showed that the public and private stakeholders held different perceptions about the roles of DMS as well as about the metrics that need to be used for evaluating DMS performance. The findings also showed that the perceptions that stakeholders hold about the roles of the DMS influence their perceptions about the performance evaluation of DMS. Research limitations/implications – The findings are based on evaluating a specific type of IOIS and sector/context. Thus, caution is required in generalising the results to other types of IOIS and social/environmental contexts. Practical implications – The study highlighted that the performance and success of DMS, and of IOIS projects in general, require the nurturing of a collaborative culture and the co-ordination of the various stakeholders’ perceptions and interests. Originality/value – The study addresses the gap in DMS performance evaluation and it contributes to the literature about IOIS evaluation by adopting a stakeholders approach.

scholarly journals Energy balance measurements over a banana orchard in the Semiarid region in the Northeast of Brazil

2009 ◽  
Vol 44 (11) ◽  
pp. 1365-1373 ◽  
Author(s):  
Carlos Antonio Costa dos Santos ◽  
Bernardo Barbosa da Silva ◽  
Tantravahi Venkata Ramana Rao ◽  
Christopher Michael Usher Neale
Keyword(s):  
Heat Flux ◽  
Energy Balance ◽  
Eddy Covariance ◽  
Heat Fluxes ◽  
Irrigation District ◽  
Semiarid Region ◽  
Energy Balance Closure ◽  
Wet Season ◽  
Growing Seasons ◽  
Eddy Covariance System

The objective of this work was to evaluate the reliability of eddy covariance measurements, analyzing the energy balance components, evapotranspiration and energy balance closure in dry and wet growing seasons, in a banana orchard. The experiment was carried out at a farm located within the irrigation district of Quixeré, in the Lower Jaguaribe basin, in Ceará state, Brazil. An eddy covariance system was used to measure the turbulent flux. An automatic weather station was installed in a grass field to obtain the reference evapotranspiration (ET0) from the combined FAO-Penman-Monteith method. Wind speed and vapor pressure deficit are the most important variables on the evaporative process in both growing seasons. In the dry season, the heat fluxes have a similar order of magnitude, and during the wet season the latent heat flux is the largest. The eddy covariance system had acceptable reliability in measuring heat flux, with actual evapotranspiration results comparing well with those obtained by using the water balance method. The energy balance closure had good results for the study area, with mean values of 0.93 and 0.86 for the dry and wet growing seasons respectively.

Sign in / Sign up

Export Citation Format

Share Document