Do Agrochemical-Free Paddy Fields Serve as Refuge Habitats for Odonata?

Agrochemical-free rice farming has attracted interest for restoring paddy field biodiversity and producing safe food. Odonata are commonly used as a biodiversity indicator in these low-input farms. However, the effect of agrochemical-free rice farming on odonate diversity has rarely been assessed over the entire emergence period of these insects. We investigated whether different farming practices, such as conventional or natural (agrochemical-and fertilizer-free) cultivation, and associated water management strategies affect the emergence rates of Odonata in paddy field landscapes in central Japan. Weekly exuviae sampling in 2017 and 2019 suggested that odonate assemblages differed between conventional and natural paddy fields, with a higher number of taxa emerging from natural paddy fields. Contrary to expectations, conventional paddy fields had equivalent or higher emergence rates of all Odonata and two numerically dominant Sympetrum species. Peak emergence periods for numerically dominant taxa differed between the farming types, with the emergence of three Sympetrum species peaking in late June in conventional paddy fields and that of S. frequens peaking in early to mid-July in natural paddy fields. Our findings suggest that both conventional and natural paddy fields are important habitats for Odonata in Japan.

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Rice Knowledge Systems in Transition

Rural-Urban Migration and Agro-Technological Change in Post-Reform China ◽

10.5117/9789463729734_ch02 ◽

2021 ◽

Author(s):

Lena Kaufmann

Keyword(s):

Paddy Field ◽

Knowledge Systems ◽

The Other ◽

Paddy Fields ◽

Urban Migration ◽

Rice Farming ◽

Other Hand ◽

The Future ◽

Rural Urban Migration ◽

The One

This chapter considers how paddy field knowledge is transmitted and how this has changed over recent decades in China, in order to better understand the problems that farmers face at the nexus of rice farming and rural-urban migration, and the options they can call on to deal with their situation. The chapter argues that there has been a complex reconfiguration of the repertoire of rice farming knowledge. On the one hand, this has created challenges for the future preservation of the paddy fields in the Chinese countryside, such as deskilling in the young migrant generation. On the other hand, it has provided peasants with an extended repertoire of knowledge they can use to handle their paddy field farming-migration predicament.

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Numerical simulation on effect of irrigation conditions on water temperature distribution in a paddy field

Paddy and Water Environment ◽

10.1007/s10333-021-00884-1 ◽

2022 ◽

Author(s):

Kazuhiro Nishida ◽

Shuichiro Yoshida ◽

Sho Shiozawa

Keyword(s):

Water Management ◽

Numerical Simulation ◽

Temperature Distribution ◽

Water Temperature ◽

Physical Model ◽

Irrigation Water ◽

Paddy Field ◽

Meteorological Conditions ◽

Paddy Fields ◽

Water Amount

AbstractWater management methods regulate water temperature in paddy fields, which affects rice growth and the environment. To understand the effect of irrigation conditions on water temperature in a paddy field, water temperature distribution under 42 different irrigation models including the use of ICT water management, which enables remote and automatic irrigation, was simulated using a physical model of heat balance. The following results were obtained: (1) Irrigation water temperature had a more significant effect on paddy water temperature close to the inlet. As the distance from the inlet increased, the water temperature converged to an equilibrium, which was determined by meteorological conditions and changes in water depth. (2) Increasing the irrigation rate with higher irrigation water amount increased the extent and magnitude of the effects of the irrigation water temperature. (3) When total irrigation water amount was the same, increasing the irrigation rate decreased the time-averaged temperature gradient effect over time across the paddy field. (4) Irrigation during the lowest and highest paddy water temperatures effectively decreased and increased the equilibrium water temperature, respectively. The results indicate that irrigation management can be used to alter and control water temperature in paddy fields, and showed the potential of ICT water management in enhancing the effect of water management in paddy fields. Our results demonstrated that a numerical simulation using a physical model for water temperature distribution is useful for revealing effective water management techniques under various irrigation methods and meteorological conditions.

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Concepts and Practices for Improving Nitrogen Management for Vegetables

HortTechnology ◽

10.21273/horttech.2.1.121 ◽

1992 ◽

Vol 2 (1) ◽

pp. 121-125 ◽

Cited By ~ 9

Author(s):

George J. Hochmuth

Keyword(s):

Water Management ◽

Management Practices ◽

Management Strategies ◽

N Fertilization ◽

Nitrogen Management ◽

Land Grant ◽

Land Grant Universities ◽

Production Practices ◽

Negative Impacts ◽

N Management

Efficient N management practices usually involve many potential strategies, but always involve choosing the correct amount of N and the coupling of N management to efficient water management. Nitrogen management strategies are integral parts of improved production practices recommended by land-grant universities such as the Institute of Food and Agricultural Sciences, Univ. of Florida. This paper, which draws heavily on research and experience in Florida, outlines the concepts and technologies for managing vegetable N fertilization to minimize negative impacts on the environment.

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Agricultural Use of Reclaimed Water - Experiences in Jordan

Water Practice & Technology ◽

10.2166/wpt.2006.040 ◽

2006 ◽

Vol 1 (2) ◽

Cited By ~ 2

Author(s):

Artur Vallentin

Keyword(s):

Water Management ◽

Irrigation Water ◽

Reclaimed Water ◽

Monitoring Systems ◽

Jordan Valley ◽

Water Management System ◽

Agricultural Use ◽

Safe Food ◽

Framework Conditions ◽

National Water

Due to extreme water scarcity Jordan is integrating reclaimed water resources in the national water management system. This paper describes the recent framework conditions for reclaimed water use in agriculture in Jordan, with a focus on the central and southern Jordan Valley. The possible impacts of lower quality irrigation water on soil, groundwater, crops and human health are considered while appropriate guidelines and monitoring proposals are being developed. Testing of the guidelines and implementation of the monitoring systems have started with the final purpose of integrating them into the Jordanian standard and legal system and thus ensuring safe food for consumers and protection of the environment.

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Evaluation of Carbon Footprints of Different Storm Water Management Strategies in Europe

Proceedings of the Water Environment Federation ◽

10.2175/193864715819558325 ◽

2015 ◽

Vol 2015 (2) ◽

pp. 1-10

Author(s):

André Niemann ◽

Thorsten Mietzel ◽

Sebastian Schmuck

Keyword(s):

Water Management ◽

Management Strategies ◽

Storm Water ◽

Storm Water Management ◽

Carbon Footprints

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The Value of a Decrease in Temperature by One Degree Celsius of the Regional Microclimate—The Cooling Effect of the Paddy Field

Atmosphere ◽

10.3390/atmos12030353 ◽

2021 ◽

Vol 12 (3) ◽

pp. 353

Author(s):

Ya-Wen Chiueh ◽

Chih-Hung Tan ◽

Hsiang-Yi Hsu

Keyword(s):

Land Use ◽

Surface Temperature ◽

Paddy Field ◽

Research Area ◽

Paddy Fields ◽

Cooling Effect ◽

Field Temperature ◽

Bare Land ◽

The Face ◽

The Difference

In the face of climate change, extreme climates are becoming more frequent. There were severe droughts in Taiwan in 2020, 2014–2015, and 2002. In these years, the paddy fields were kept fallow to save water and transfer agricultural water to non-agricultural use. On the other hand, with global warming, the existence of paddy fields may be one of the natural solutions to regional temperature mitigation. This study used remote sensing to quantify the difference in temperature between paddy fields and urban areas. The result of overall surface temperature deductive analysis revealed that the temperature in the whole Taoyuan research area was 1.2 °C higher in 2002 than in 2003 because of fallowing of the paddy field, while in the Hsinchu research area, it was 1.5 °C higher in 2002 than in 2003, due to the same reason described above. In terms of the difference in land use, for the Hsinchu research area, the surface temperature deductive result showed that the average paddy field temperature in 2002 was 22.3 °C (sample area average), which was 7.7 °C lower than that of the building and road point and 4.3 °C lower than that of the bare land point. The average paddy field temperature in 2003 was 19.2 °C (sample area average), which was 10.1 °C lower than that of the building and road point and 8.3 °C lower than that of the bare land point. Then this study evaluated the economic valuation of the paddy field cooling effect using the contingent valuation method. Through the paddy field cooling effect and in the face of worsening extreme global climate, the willingness to pay (WTP) of the respondents in Taiwan for a decrease of 1 °C with regard to the regional microclimate was evaluated. It was found that people in Taiwan are willing to pay an extra 8.89 USD/per kg rice/year for the paddy for a decrease in temperature by 1 °C in the regional microclimate due to the paddy field. Furthermore, this study applied the benefits transfer method to evaluate the value of a decrease of 1 °C in the regional microclimate in Taiwan. The value of a decrease of 1 °C in the regional microclimate in Taiwan is 9,693,144,279 USD/year. In this regard, the economic value of 1 °C must not be underestimated. In conclusion, more caution is needed while making decisions to change the land use of paddy fields to other land uses.

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Evaluation of thiobencarb runoff from rice farming practices in a California watershed using an integrated RiceWQ-AnnAGNPS system

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.144898 ◽

2021 ◽

Vol 767 ◽

pp. 144898

Author(s):

Ruoyu Wang ◽

Ronald L. Bingner ◽

Yongping Yuan ◽

Martin Locke ◽

Glenn Herring ◽

...

Keyword(s):

Rice Farming ◽

Farming Practices

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Cyanobacterial Abundance and Microcystin Profiles in Two Southern British Lakes: The Importance of Abiotic and Biotic Interactions

Toxins ◽

10.3390/toxins12080503 ◽

2020 ◽

Vol 12 (8) ◽

pp. 503 ◽

Cited By ~ 1

Author(s):

David M. Hartnell ◽

Ian J. Chapman ◽

Nick G. H. Taylor ◽

Genoveva F. Esteban ◽

Andrew D. Turner ◽

...

Keyword(s):

Water Management ◽

Linear Regression Analysis ◽

Management Strategies ◽

Biotic Interactions ◽

Cost Effective ◽

Multiple Linear Regression Analysis ◽

Tandem Mass ◽

Recreational Waters ◽

Cyanobacteria Blooms ◽

Freshwater Bodies

Freshwater cyanobacteria blooms represent a risk to ecological and human health through induction of anoxia and release of potent toxins; both conditions require water management to mitigate risks. Many cyanobacteria taxa may produce microcystins, a group of toxic cyclic heptapeptides. Understanding the relationships between the abiotic drivers of microcystins and their occurrence would assist in the implementation of targeted, cost-effective solutions to maintain safe drinking and recreational waters. Cyanobacteria and microcystins were measured by flow cytometry and liquid chromatography coupled to tandem mass spectrometry in two interconnected reservoirs varying in age and management regimes, in southern Britain over a 12-month period. Microcystins were detected in both reservoirs, with significantly higher concentrations in the southern lake (maximum concentration >7 µg L−1). Elevated microcystin concentrations were not positively correlated with numbers of cyanobacterial cells, but multiple linear regression analysis suggested temperature and dissolved oxygen explained a significant amount of the variability in microcystin across both reservoirs. The presence of a managed fishery in one lake was associated with decreased microcystin levels, suggestive of top down control on cyanobacterial populations. This study supports the need to develop inclusive, multifactor holistic water management strategies to control cyanobacterial risks in freshwater bodies.

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Effects of Contemporary Land Use Types and Conversions from Wetland to Paddy Field or Dry Land on Soil Organic Carbon Fractions

Sustainability ◽

10.3390/su12052094 ◽

2020 ◽

Vol 12 (5) ◽

pp. 2094

Author(s):

Di Zhao ◽

Junyu Dong ◽

Shuping Ji ◽

Miansong Huang ◽

Quan Quan ◽

...

Keyword(s):

Land Use ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Constructed Wetland ◽

Paddy Field ◽

Heavy Fraction ◽

Light Fraction ◽

Paddy Fields ◽

Dry Land ◽

Natural Wetlands

Soil organic carbon (SOC) concentration is closely related to soil quality and climate change. The objectives of this study were to estimate the effects of contemporary land use on SOC concentrations at 0–20 cm depths, and to investigate the dynamics of SOC in paddy-field soil and dry-land soil after their conversion from natural wetlands (20 and 30 years ago). We investigated the dissolved organic carbon (DOC), light fraction organic carbon (LFOC), heavy fraction organic carbon (HFOC), and other soil properties (i.e., moisture content, bulk density, pH, clay, sand, silt, available phosphorous, light fraction nitrogen, and heavy fraction nitrogen) in natural wetlands, constructed wetlands, fishponds, paddy fields, and soybean fields. The results indicated that the content of DOC increased 17% in constructed wetland and decreased 39% in fishponds, and the content of HFOC in constructed wetland and fishponds increased 50% and 8%, respectively, compared with that in natural wetlands at 0–20 cm. After the conversion of a wetland, the content of HFOC increased 72% in the paddy fields and decreased 62% in the dry land, while the content of DOC and LFOC decreased in both types. In the paddy fields, LFOC and HFOC content in the topmost 0.2 m of the soil layer was significantly higher compared to the layer below (from 0.2 to 0.6 m), and there were no significant differences observed in the dry land. The findings suggest that the paddy fields can sequester organic carbon through the accumulation of HFOC. However, the HFOC content decreased 22% after 10 years of cultivation with the decrease of clay content, indicating that paddy fields need to favor clay accumulation for the purpose of enhancing carbon sequestration in the paddy fields.

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