The Fallow Period Plays an Important Role in Annual CH4 Emission in a Rice Paddy in Southern Brazil

Paddy fields are significant anthropogenic sources of methane (CH4) emissions. In southern Brazil, rice is grown in lowland flooded areas once a year, followed by a long fallow period. This study aimed to measure CH4 fluxes in a rice paddy field in southern Brazil during the rice-growing season of 2015/2016 and the following fallow period. The fluxes were estimated using the eddy covariance (EC) technique and soil chamber (SC). Diurnal and seasonal variations of CH4 fluxes and potential meteorological drivers were analyzed. The CH4 fluxes showed distinct diurnal variations in each analyzed subperiod (vegetative, reproductive, pre-harvest, no rice, and land preparation), characterized by a single-peak diurnal pattern. The variables that most influenced methane emissions were air and surface temperatures. In the growing season, the rice vegetative stage was responsible for most of the measured emissions. The accumulated annual emission estimated was 44.88 g CH4 m−2 y−1, being 64% (28.50 g CH4 m−2) due to the rice-growing season and 36% (16.38 g CH4 m−2) due to the fallow period. These results show the importance of including fallow periods in strategies to mitigate methane emissions in flood irrigated rice-growing areas.

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Nitrogen fertilizer application in the rice-growing season can stimulate methane emissions during the subsequent flooded fallow period

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.140632 ◽

2020 ◽

Vol 744 ◽

pp. 140632

Author(s):

Peng Xu ◽

Wei Zhou ◽

Mengdie Jiang ◽

Imran Khan ◽

Muhammad Shaaban ◽

...

Keyword(s):

Nitrogen Fertilizer ◽

Growing Season ◽

Fertilizer Application ◽

Methane Emissions ◽

Fallow Period ◽

Rice Growing Season

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Rice herbicide monitoring in two Brazilian rivers during the rice growing season

Scientia Agricola ◽

10.1590/s0103-90162007000200005 ◽

2007 ◽

Vol 64 (2) ◽

pp. 131-137 ◽

Cited By ~ 36

Author(s):

Enio Marchesan ◽

Renato Zanella ◽

Luis Antonio de Avila ◽

Edinalvo Rabaioli Camargo ◽

Sérgio Luiz de Oliveira Machado ◽

...

Keyword(s):

River Water ◽

Environmental Contamination ◽

Growing Season ◽

Rainfall Regime ◽

Irrigated Rice ◽

Herbicide Concentration ◽

Rice Water ◽

Flooded Areas ◽

Rice Growing Season

Irrigated rice production can involve environmental contamination with pesticides due to the proximity of the fields to rivers and to management problems. During three years (2000 to 2003) the rice herbicides clomazone, propanil and quinclorac were quantified in water during the rice growing season, in the Vacacaí and Vacacaí-Mirim Rivers, located in Rio Grande do Sul (RS) State, Brazil. Water samples were taken at several locations in each river, selected by their importance in terms of rice drainage area. The samples were analyzed by HPLC-UV. At least one herbicide was detected in 41% of the samples from the Vacacaí River and 33% from the Vacacaí-Mirim River. The most frequent herbicide in both rivers and in each year was clomazone. The amount of herbicides in the river water was dependent on the rainfall regime. River water contamination by rice herbicides is probably caused by the rice water management used in the fields. The maintenance of flooded areas makes herbicides prone to contaminate the environment. To reduce the environmental contamination risk it is necessary to adopt measures to avoid overflow of flooded rice fields, keeping paddy water in the field for time enough to reduce the herbicide concentration before its release and enhancing the quality of the levees to reduce the probability of paddy rice overflow.

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Understanding Farmer and Government Measure in Rat Pests Control in Rice Fields

Journal La Lifesci ◽

10.37899/journallalifesci.v2i2.373 ◽

2021 ◽

Vol 2 (2) ◽

pp. 24-30

Author(s):

Thuy Xuan ◽

Tiuen Yen ◽

Tuyet Caugh

Keyword(s):

Population Density ◽

Rice Field ◽

Growing Season ◽

Rice Paddy ◽

The Other ◽

Cropping Pattern ◽

Population Peak ◽

Government Measure ◽

Intensive Control ◽

Rice Growing Season

This paper discusses the control of rat pets through highlighting its population growth, ecosystem, types and possible mechanism to use. During extended periods of fallow, rice field rats tend to congregate in escape places (refuge regions) such as bushes, yards, or rice warehouses. Rice plants suffered damage equivalent to five times their feeding requirements when rats were present. Rats damage plants from the tiller stage to the maximal tiller stages by devouring the growth point and the soft base of the stem while leaving the other portions of the plant unharmed. Without intensive control efforts (since the start of MT1), the rat population density on MT2 is confirmed to be higher and poses a serious threat to the success of MT2 harvesting. In one rice growing season, there is one population peak so in the rice-paddy-fallow cropping pattern there are two (2) population peaks.

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Appropriate frequency and time of day to measure methane emissions from an irrigated rice paddy in Japan using the manual closed chamber method

Greenhouse Gas Measurement and Management ◽

10.1080/20430779.2012.729988 ◽

2012 ◽

Vol 2 (2-3) ◽

pp. 118-128 ◽

Cited By ~ 25

Author(s):

Kazunori Minamikawa ◽

Kazuyuki Yagi ◽

Takeshi Tokida ◽

Bjoern Ole Sander ◽

Reiner Wassmann

Keyword(s):

Rice Paddy ◽

Methane Emissions ◽

Time Of Day ◽

Closed Chamber ◽

Irrigated Rice ◽

Chamber Method ◽

Closed Chamber Method

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Effect of Heat Resource Effectiveness Change on Rice Potential Yield in Southern China

Processes ◽

10.3390/pr9050896 ◽

2021 ◽

Vol 9 (5) ◽

pp. 896

Author(s):

Qing Ye ◽

Xiaoguang Yang ◽

Wenjuan Xie ◽

Junmeng Yao ◽

Zhe Cai

Keyword(s):

Southern China ◽

Cropping Systems ◽

Reduction Rate ◽

Growing Season ◽

Scientific Basis ◽

Yield Reduction ◽

Percentage Increase ◽

Potential Yield ◽

Effective Heat ◽

Rice Growing Season

During the rice growing season, farmers’ decisions about cropping systems and seed varieties directly affect the utilization of heat resource, and eventually affect the potential yield. In this study, we used the hourly accumulated temperature model to calculate the available heat resource as well as the effective heat resource in southern China. We conducted a spatiotemporal analysis of the heat resource effectiveness during rice growing season and an impact assessment of heat resource effectiveness on rice potential yield and cereal yield reduction. The results showed that, during the period of 1951–2015, heat resource effectiveness generally declined in the rice cropping area of southern China. And this decrease worsened during the most recent three decades compared with the period of 1951–1980. A strong correlation was detected between heat resource effectiveness and rice potential yield in the study area. When the effective heat resource during the growing season increased by 1 °C·d, rice potential yield would increase by 14 kg ha−1. For each percentage increase in heat resource effectiveness, the rice potential yield reduction rate would go down by 0.65%. This agro-climatological study aims to offer a scientific basis for rice production decisions in southern China, such as when to plant, which varieties to choose and so on.

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Sensitivity of wetland methane emissions to model assumptions: application and model testing against site observations

Biogeosciences ◽

10.5194/bg-9-2793-2012 ◽

2012 ◽

Vol 9 (7) ◽

pp. 2793-2819 ◽

Cited By ~ 52

Author(s):

L. Meng ◽

P. G. M. Hess ◽

N. M. Mahowald ◽

J. B. Yavitt ◽

W. J. Riley ◽

...

Keyword(s):

Soil Ph ◽

High Latitude ◽

Large Range ◽

Rice Paddy ◽

Temporal Variations ◽

Methane Emissions ◽

Biogeochemical Model ◽

Atmospheric Methane ◽

Rice Paddies ◽

Community Land Model

Abstract. Methane emissions from natural wetlands and rice paddies constitute a large proportion of atmospheric methane, but the magnitude and year-to-year variation of these methane sources are still unpredictable. Here we describe and evaluate the integration of a methane biogeochemical model (CLM4Me; Riley et al., 2011) into the Community Land Model 4.0 (CLM4CN) in order to better explain spatial and temporal variations in methane emissions. We test new functions for soil pH and redox potential that impact microbial methane production in soils. We also constrain aerenchyma in plants in always-inundated areas in order to better represent wetland vegetation. Satellite inundated fraction is explicitly prescribed in the model, because there are large differences between simulated fractional inundation and satellite observations, and thus we do not use CLM4-simulated hydrology to predict inundated areas. A rice paddy module is also incorporated into the model, where the fraction of land used for rice production is explicitly prescribed. The model is evaluated at the site level with vegetation cover and water table prescribed from measurements. Explicit site level evaluations of simulated methane emissions are quite different than evaluating the grid-cell averaged emissions against available measurements. Using a baseline set of parameter values, our model-estimated average global wetland emissions for the period 1993–2004 were 256 Tg CH4 yr−1 (including the soil sink) and rice paddy emissions in the year 2000 were 42 Tg CH4 yr−1. Tropical wetlands contributed 201 Tg CH4 yr−1, or 78% of the global wetland flux. Northern latitude (>50 N) systems contributed 12 Tg CH4 yr−1. However, sensitivity studies show a large range (150–346 Tg CH4 yr−1) in predicted global methane emissions (excluding emissions from rice paddies). The large range is sensitive to (1) the amount of methane transported through aerenchyma, (2) soil pH (±100 Tg CH4 yr−1), and (3) redox inhibition (±45 Tg CH4 yr−1). Results are sensitive to biases in the CLMCN and to errors in the satellite inundation fraction. In particular, the high latitude methane emission estimate may be biased low due to both underestimates in the high-latitude inundated area captured by satellites and unrealistically low high-latitude productivity and soil carbon predicted by CLM4.

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Assessment of Ammonia Volatilization Losses and Nitrogen Utilization during the Rice Growing Season in Alkaline Salt-Affected Soils

Sustainability ◽

10.3390/su9010132 ◽

2017 ◽

Vol 9 (1) ◽

pp. 132 ◽

Cited By ~ 9

Author(s):

Yangyang Li ◽

Lihua Huang ◽

Huan Zhang ◽

Mingming Wang ◽

Zhengwei Liang

Keyword(s):

Ammonia Volatilization ◽

Growing Season ◽

Nitrogen Utilization ◽

Alkaline Salt ◽

Salt Affected Soils ◽

Rice Growing Season

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Analisis Kebutuhan Air Irigasi Menggunakan CROPWAT 8.0 pada Daerah Irigasi Krueng Jreu Kabupaten Aceh Besar

Jurnal Ilmiah Mahasiswa Pertanian ◽

10.17969/jimfp.v4i4.12758 ◽

2020 ◽

Vol 4 (4) ◽

pp. 412-421

Author(s):

Mahendra Rizqi ◽

Muhammad Yasar Yasar ◽

Dewi Sri Jayanti

Keyword(s):

Irrigation Water ◽

Food Production ◽

Rice Paddy ◽

Irrigation Water Requirement ◽

Water Requirements ◽

Cropping Patterns ◽

Irrigation Area ◽

Land Preparation ◽

Increase Food Production ◽

Manual Calculation

Abstrak. Salah satu usaha peningkatan produksi pangan khususnya padi adalah tersedianya air irigasi di areal sawah sesuai dengan kebutuhan. Kebutuhan air yang diperlukan pada areal irigasi besarnya bervariasi sesuai keadaan untuk memenuhi kebutuhan evapotranspirasi, kehilangan air, kebutuhan air untuk tanaman dengan memperhatikan jumlah air yang diberikan oleh alam melalui hujan dan kontribusi air tanah. Pengaplikasian CROPWAT 8.0 ini sangat membantu dalam pengelolaan data sehingga menghasilkan data yang dapat digunakan. Tujuan penelitian ini adalah untuk menghitung kebutuhan air irigasi pada Daerah Irigasi Krueng Jreu dengan menggunakan software CROPWAT 8.0. Metode penelitian adalah menentukan parameter, pengumpulan data dan pengolahan data. Data yang digunakan dalam penelitian ini adalah data luas areal yang dialiri, data-data untuk menghitung evapotranspirasi meliputi temperatur, kelembaban relatif, kecepatan angin, lama penyinaran matahari, curah hujan, pola dan jadwal tanam yang dianjurkan di daerah penelitian. Hasil penelitian yang telah dilakukan diperoleh Nilai evapotranspirasi potensial (ET0) rata-rata di Daerah Irigasi Krueng Jreu adalah sebesar 3,75 mm/hari, curah hujan efektif (Re) rata-rata di Daerah Irigasi Krueng Jreu adalah sebesar 3,09 mm/hari, kebutuhan air untuk penyiapan lahan adalah sebesar 11,35 mm/hari untuk Bulan November dan sebesar 11,71 mm/hari untuk Bulan Mei, kebutuhan bersih air di sawah (NFR) untuk padi rendeng dan padi gadu yaitu sebesar 11,22 mm/hari dan 25,34 mm/hari, dan kebutuhan air pada pintu pengambilan (DR) untuk padi rendeng dan padi gadu yaitu sebesar 17,27 mm/hari dan 38,98 mm/hari. Kebutuhan air irigasi di Darah Irigasi Krueng Jreu dengan total luas area sebesar 3.287 ha dengan kebutuhan air irigasi pola tanam padi-padi yang dimulai awal pengolahan lahan pada awal Bulan November maka didapatkan kebutuhan air irigasi maksimal yaitu terjadi pada Bulan Juli dengan perhitungan CROPWAT yaitu sebesar 14,9 m3/detik dan untuk perhitungan manual yaitu sebesar 6,26 m3/detik. Kebutuhan air irigasi minimum yaitu terjadi pada Bulan Desember dengan perhitungan CROPWAT yaitu sebesar 0,00 m3/detik dan perhitungan manual yaitu sebesar 0,45 m3/detik.Analysis of Irrigation Water Requirement Using CROPWAT 8.0 in Krueng Jreu Irrigation Area of Aceh Besar RegencyAbstract. One of the efforts to increase food production, especially rice, is the availability of irrigation water in paddy fields according to their needs. The required water needs in the area of irrigation varies according the State needs for evapotranspiration, water loss, water needs for plants with attention to the amount of water given by nature through the rain and the contribution of groundwater. The application of Cropwat 8.0 is very helpful in managing data so as to produce data that can be used. The purpose of this study was to calculate irrigation water requirements in the Krueng Jreu Irrigation Area using Cropwat 8.0 software. The research method is determining parameters, data collection and data processing. The data used in this study is the data area that is flowed, the data for calculating evapotranspiration include: temperature, relative humidity, wind speed, duration of solar radiation, rainfall, patterns, and planting schedules recommended in the study area. Based on the results of the research that has been carried out, it can be concluded as follows: the average evapotranspiration value (ET0) in the Krueng Jreu Irrigation Area is 3,75 mm/day, the effective rainfall (Re) in the Krueng Jreu Irrigation Area is amounting to 3,09 mm/day, water requirements for land preparation of 11,35 mm/day in November and 11,71 mm/day in Mei, clean water requirements in rice fields (NFR) for rendeng rice and gadu rice which amounted to 11,22 mm/day and 25,34 mm/day, and water requirements on the retrieval gate (DR) for rendeng rice and gadu rice were equal to 17,27 mm/day and 38,98 mm/day. Irrigation water needs in Krueng Jreu Irrigation Blood with a total area of 3.287 ha with irrigation water requirements for rice-paddy cropping patterns that were started at the beginning of land processing at the beginning of November the maximum irrigation water needs were obtained in July with Cropwat calculations that is equal to 14,9 m3/second and for manual calculations amounting to 6,26 m3/sec. For minimum irrigation water needs, that occurs in December with a Cropwat calculation is 0,00 m3/second and manual calculation of 0,45 m3/sec.

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