Paddy Irrigation Research Articles

Fish community in a fish-retreat ditch created in a paddy irrigation and drainage system near the sea

Fish community in a fish-retreat ditch created in a paddy irrigation and drainage system near the sea

The Change of the Water Demand and Delivery Water Requirement for a Large-sized Paddy Irrigation under Urbanization

The Change of the Water Demand and Delivery Water Requirement for a Large-sized Paddy Irrigation under Urbanization

Associations between inorganic arsenic in rice and groundwater arsenic in the Mekong Delta

There is growing concern regarding human dietary exposure to arsenic (As) via consumption of rice. The concentration and speciation of As in rice are highly variable, and models describing rice As speciation as a function of environmental covariates remain elusive. We conducted a survey of paddy rice and soil in the Mekong Delta with the objective of linking patterns in rice As content to soil chemical variables or hydrogeological parameters. The sum of As species (ΣAs) in husked rice averaged 243 μg/kg and the average inorganic As (iAs) content was 84%. There was no relationship found between rice As concentration or speciation and As levels in soil. However, mean As concentrations in groundwater near rice sampling locations were strongly correlated with grain ΣAs and iAs over a large part of the study region, despite the fact that groundwater is not commonly used for rice paddy irrigation in this region. We hypothesize that surficial sediments with high concentrations of soluble and plant-available As also serve as sources of arsenic to downgradient shallow aquifers, explaining the observed associations between rice and groundwater As. This study suggests that shallow groundwater As concentrations may serve as a useful indicator for locations at risk of elevated iAs concentrations in rice.

Irrigation with secondary municipal-treated wastewater: Potential effects, accumulation of typical antibiotics and grain quality responses in rice (Oryza sativa L.)

Using secondary treated wastewater to irrigate paddies presents an exposure pathway for antibiotics to enter the terrestrial food chain. To date, there has been no information on the biochemical reactions and antibiotic uptake in rice plants irrigated with secondary treated wastewater. The present study investigated antibiotic uptake and concentration-response trends in rice tissues and evaluated the effects of typical antibiotics (tetracycline, roxithromycin, ofloxacin, and sulfamethoxazole) on rice growth, grain yield and quality, and rice physiobiochemical characters via irrigation using treated wastewater augmented with varying concentrations (0–500 µg/L) in paddies. The results showed that the antibiotic accumulation in rice plants irrigated with treated wastewater was limited, and the studied antibiotics were not detected in rice grains (edible parts). The ability of rice to withstand certain antibiotics and grow in a healthy manner is attributed to the capacity to maintain reasonably normal photosynthesis activity and to elevate antioxidative defenses. The highest antibiotic concentration (500 µg/L) did not reduce the processing quality of the rice grain, but it enhanced the cooking and eating quality. From the obtained results, it can be concluded that secondary treated wastewater for paddy irrigation is an alternative water resource securing protection from the environment and rice grain quality.

Sources, Influencing Factors, and Pollution Process of Inorganic Nitrogen in Shallow Groundwater of a Typical Agricultural Area in Northeast China

As one of the largest agricultural areas, the Sanjiang Plain of Northeast China has faced serious inorganic nitrogen pollution of groundwater, but the sources and the formation mechanism of pollution in the regional shallow groundwater remain unclear, which constrains the progress of pollution control and agricultural development planning. An investigation on potential nitrogen sources, groundwater inorganic nitrogen compounds (NH4+, NO3−, NO2−), and topsoil total nitrogen concentration (TN) was conducted in a typical paddy irrigation area of Sanjiang Plain. Multivariate statistical analysis combined with geospatial-based assessment was applied to identify the sources, determine the governing influencing factors, and analyze the formation process of inorganic nitrogen compounds in shallow groundwater. The results show that the land use type, oxidation-reduction potential (Eh), groundwater depth, NO2− concentration, and electrical conductivity (EC) are highly correlated with the NO3− pollution in groundwater, while DO and Eh affected the distribution of NH4+ most; the high concentrations of NO3− in sampling wells are most likely to be found in the residential land and are distributed mainly in densely populated areas, whereas the NH4+ compounds are most likely to accumulate in the paddy field or the lands surrounded by paddy field and reach the highest level in the northwest of the area, where the fields were cultivated intensively with higher fertilization rates and highest values of topsoil TN. From the results, it can be concluded that that the NO3− compounds in groundwater originated from manure and domestic waste and accumulated in the oxidizing environment, while the NH4+ compounds were derived from N fertilization and remained steady in the reducing environment. NO2− compounds in groundwater were the immediate products of nitrification as a result of microorganism activities.

Growth and production of sixth generation of brown rice mutants in a high altitude location

This paper presents the result of an experiment which aimed to determine the growth and production of some 6th generation Sinjai brown rice mutants (M6) in the highlands. The experiment was conducted in an irrigated paddy field with a height of 750 meters above sea level. The arrangement was a randomized block design (RBD). The treatments consisted of 8 brown rice mutant lines (g1, g2, g3, g4, g5, g6, g7, g8) and Sinjai brown rice parent as control (g9). The results showed that the mutant lines g2 and g3 produced the highest grain production of 3.10 tons ha−1 and 3.13 tons ha−1 respectively. Mutant strains g2 and g3 were short in plant height with a high number of productive tillers, flowering age and a faster harvest time, as well as highest grain length. g2 and g3 strains are the most potential lines to be developed in the highlands. The growth character and production components that have a real positive correlation to production per hectare are production per clump and presentation of filled grain per panicle.

Factors Affecting Rice Production and Land Usages in Banten Province, Indonesia

Banten Province has a harvested area of paddy fields on the 2017 year of 415,687 ha and production of 2,369,731 tons of unhusked rice. The objectives of this study are: 1) Knowing the priority of resources and agricultural inputs use for food production, 2) Knowing the factors that influence the productivity of rice in irrigated land in Banten Province, 3) Knowing the efficiency of the use of production inputs. The sampling method used purposive sampling with 90 respondents. The analytical method used the Analytical Hierarchy Process (AHP) and multiple linear regression of Cobb Douglas production functions. The results of the study are: 1) The priority strategy in increasing food production is to increase the use of irrigated rice fields, so that the goal is achieved by increasing the crop index, this can be done by prioritizing the optimization of agricultural machinery 2) Significant factors that affecting the production of paddy rice in the irrigated wetland paddy field in Rainy Season 2017/2018 are the use of urea fertilizer, the amount of use of solid organic fertilizer, the amount of use of human labor rent, and the arable land area, 3). The cumulative elasticity is 1.45, which is elastic, meaning that the addition of 1% of the production factor will increase production by 1.45% or increasing return to scale. So rice farming in irrigated land is relatively efficient. To increase production, it is necessary to increase rice productivity and crop index in irrigated paddy fields.
 
 Keywords: Factors production, efficiency, priority analysis, rice, land usage.

Combined impact of pesticides and other environmental stressors on animal diversity in irrigation ponds.

Rice paddy irrigation ponds can sustain surprisingly high taxonomic richness and make significant contributions to regional biodiversity. We evaluated the impacts of pesticides and other environmental stressors (including eutrophication, decreased macrophyte coverage, physical habitat destruction, and invasive alien species) on the taxonomic richness of freshwater animals in 21 irrigation ponds in Japan. We sampled a wide range of freshwater animals (reptiles, amphibians, fishes, mollusks, crustaceans, insects, annelids, bryozoans, and sponges) and surveyed environmental variables related to pesticide contamination and other stressors listed above. Statistical analyses comprised contraction of highly correlated environmental variables, best-subset model selection, stepwise model selection, and permutation tests. Results showed that: (i) probenazole (fungicide) was a significant stressor on fish (i.e., contamination with this compound had a significantly negative correlation with fish taxonomic richness), (ii) the interaction of BPMC (insecticide; also known as fenobucarb) and bluegill (invasive alien fish) was a significant stressor on a "large insect" category (Coleoptera, Ephemeroptera, Hemiptera, Lepidoptera, Odonata, and Trichoptera), (iii) the interaction of BPMC and concrete bank protection was a significant stressor on an "invertebrate" category, (iv) the combined impacts of BPMC and the other stressors on the invertebrate and large insect categories resulted in an estimated mean loss of taxonomic richness by 15% and 77%, respectively, in comparison with a hypothetical pond with preferable conditions.

Identifikasi Status Hara N Lahan Sawah pada Daerah Irigasi Kedunglimus Arca Kiri, Di Kecamatan Kembaran Kabupaten Banyumas

Paddy soil is land that is important in Indonesia as a major resource for growing rice in rice production. The main problems in rice cultivation in paddy fields is the transfer function, especially fertile and irrigated paddy fields into industrial areas and urban sprawl. The study aims to determine the amount of the nutrient content of N and determine the availability of nutrients N correlation with the production of rice in paddy fields in the area of the left arca of weir irrigation in Sub-District Kembaran Banyumas. The experiment was conducted in paddy fields in the area of the left arca of weir irrigation in Sub-District Kembaran Banyumas and followed with the analysis of the soil at the Laboratory Institute for Agricultural Technology in Yogyakarta and in the Laboratory of Soil Science, Faculty of Agriculture Unsoed. The experiment was conducted in March and May 2015. The study was conducted by survey method, in-depth review the level of accuracy (semi detail) with scale in map 1: 50,000. The determination of sample points is based on Homogeneous Soil Map Unit (SLH), which is made by overlay map on the map of soil types, slope maps and land use maps of research areas. The number of samples is 8, which is located on the 5 villages. The variables were observed and measured in the study include the main variables, namely N-total and N-available and include support variable-organic C content, soil pH, pH of water irrigation, CEC and interviews with farmers. The results showed that N-total content at all SLH is low, i.e. 0.166% in SLH A1f and 0.173% in SLH A2f . The content of N-available (N-NH4) in all SLH are 157 ppm in SLH A1f and 163 ppm in SLH A2f.

Multiple‐indicator study of the response of groundwater recharge sources to highly turbid river water after a landslide in the Tedori River alluvial fan, Japan

AbstractThe large volume of groundwater stored in the Tedori River alluvial fan, Ishikawa Prefecture, Japan, is an important source of local drinking and industrial water. The Tedori River was observed to be highly turbid from the beginning of May 2015 to at least November 2017 due to a landslide in the upper reach of the river. After the landslide, the groundwater level was drawn down by several to 10 m near the middle river section during paddy irrigation periods in 2015 and 2016. This study addresses the impacts of the highly turbid water on groundwater recharge from the river and paddy fields. In 2016, we sampled groundwater, river water, paddy irrigation water, paddy ponding water, and precipitation five times at 2‐month intervals. We analysed the H, O, and Sr stable isotopic compositions and major dissolved ion (and Sr) concentrations and compared our data to previous data obtained in June 2011. Ca, Sr, Cl, SO4, and TN concentrations and δ18O values were higher in June 2016 than in June 2011; these increases were more extreme along the left bank of the Tedori River than along the right bank. We explored the mixing of Tedori River water with groundwater using a two‐endmember mixing model based on their Sr concentrations and isotopic compositions. Compared to June 2011, mixing ratios were decreased near the Tedori River in 2016, and larger decreases were observed along the left bank and in the middle stream area. These results confirm that the contribution to groundwater recharge from the river decreased during the turbidity event, particularly along the left bank.

EFISIENSI PENGGUNAAN INPUT PRODUKSI USAHATANI PADI SAWAH ANTARA SISTEM IRIGASI TEKNIS DAN SISTEM POMPANISASI

This research to find out the magnitude of the effect of the use of inputs both simultaneously and partially and the level of price efficiency in the use of inputs in the technical lowland rice farming in the Kasemen District and pumping systems in the Carenang District. Simple random sampling method as a method for sampling. The number of respondents for the technical irrigated paddy farmers in Kasemen District was 44 farmers, and for the pumping paddy farmers in Carenang District the same amounted to 44 farmers. The data processing method is to use Cobb-Douglas production function analysis and price efficiency. Based on the results of the study showed 1) in the F test (simultaneous), the use of land area, seeds, labor and urea fertilizer had a significant effect on the production of lowland rice both in Kasemen and Carenang Districts. 2) by t test (partial), the use of inputs that significantly influence the production of lowland rice in Kasemen District and in Carenang District namely urea fertilizer, land area and seeds. 3) The level of efficiency for technical irrigation systems is know to use land area inputs of 1.28 (not efficient), seeds of 18.55 (not efficient), labor of 0.11 (inefficient) and urea fertilizer of 14.45 (not efficient). Meanwhile, for pumping paddy farming, it is known that the level of efficiency of the use of inputs is land area of 3.22 (not efficient), seeds of 8.31 (not efficient), labor of 0.45 (inefficient) and urea fertilizer of 20.55 (not efficient).

Mapping Paddy Fields in Japan by Using a Sentinel-1 SAR Time Series Supplemented by Sentinel-2 Images on Google Earth Engine

Paddy fields play very important environmental roles in food security, water resource management, biodiversity conservation, and climate change. Therefore, reliable broad-scale paddy field maps are essential for understanding these issues related to rice and paddy fields. Here, we propose a novel paddy field mapping method that uses Sentinel-1 synthetic aperture radar (SAR) time series that are robust for cloud cover, supplemented by Sentinel-2 optical images that are more reliable than SAR data for extracting irrigated paddy fields. Paddy fields were provisionally specified by using the Sentinel-1 SAR data and a conventional decision tree method. Then, an additional mask using water and vegetation indexes based on Sentinel-2 optical images was overlaid to remove non-paddy field areas. We used the proposed method to develop a paddy field map for Japan in 2018 with a 30 m spatial resolution. The producer’s accuracy of this map (92.4%) for non-paddy reference agricultural fields was much higher than that of a map developed by the conventional method (57.0%) using only Sentinel-1 data. Our proposed method also reproduced paddy field areas at the prefecture scale better than existing paddy field maps developed by a remote sensing approach.

Solar Powered Paddy Irrigation System Using Arduino UNO Microcontroller: Battery Performance

This project is about the innovation of automated irrigation system at paddy field. Paddy irrigation system traditionally was depending on raining seasons. The changing of raining seasons will affect paddy growth. The farmer will use water pump sourced from diesel to drain water into the paddy field. The diesel water pump produces smoke that causes air pollution and bad health to the farmer. Moreover, diesel was non-reusable energy plus the manual control of irrigation system wastes time and human energy to operate the water pump and observe the water level. This project proposed the photovoltaic system to power the irrigation system and develop the prototype to represent the element of real irrigation system at the paddy field. Standalone photovoltaic system consists of solar panel, battery as energy storage, solar charger controller and water pump and the irrigation system is fully automated system controlled by Arduino UNO. Result obtain the solar-powered paddy irrigation system success coverall supply electricity to the irrigation system. The water pump only runs when low water level which measures by polypropylene float switch. The proposed project can produce efficient irrigation system, reduce the air pollution at paddy field and make farmer better health.

Improvement of the Irrigation Scheme in the ORCHIDEE Land Surface Model and Impacts of Irrigation on Regional Water Budgets Over China.

In China, irrigation is widespread in 40.7% cropland to sustain crop yields. By its action on water cycle, irrigation affects water resources and local climate. In this study, a new irrigation module, including flood and paddy irrigation technologies, was developed in the ORCHIDEE‐CROP land surface model which describes crop phenology and growth in order to estimate irrigation demands over China from 1982 to 2014. Three simulations were performed including NI (no irrigation), IR (with irrigation limited by local water resources), and FI (with irrigation demand fulfilled). Observations and census data were used to validate the simulations. Results showed that the estimated irrigation water withdrawal ( W) based on IR and FI scenarios bracket statistical W with fair spatial agreements ( r=0.68±0.07; p<0.01). Improving irrigation efficiency was found to be the dominant factor leading to the observed W decrease. By comparing simulated total water storage (TWS) with GRACE observations, we found that simulated TWS with irrigation well explained the TWS variation over China. However, our simulation overestimated the seasonality of TWS in the Yangtze River Basin due to ignoring regulation of artificial reservoirs. The observed TWS decrease in the Yellow River Basin caused by groundwater depletion was not totally captured in our simulation, but it can be inferred by combining simulated TWS with census data. Moreover, we demonstrated that land use change tended to drive W locally but had little effect on total W over China due to water resources limitation.

Zeolite amendment enhances rice production, nitrogen accumulation and translocation in wetting and drying irrigation paddy field

Zeolite (Z) has been widely used for improving rice production, but there is a lack of information on how nitrogen (N) accumulation and translocation affect yield performance of paddy field in the alternate wetting and drying irrigation (AWD) amended with zeolite. In this study, a 2-year field experiment with installed lysimeters was carried out to determine the influence of Z application (0, 5 and 10 t Z ha−1) on rice yield, tiller number, leaf area index (LAI), dry matter accumulation and translocation (DMA and DMT), N accumulation and translocation (NA and NT), inorganic N content in soil under two irrigation regimes (CF: continuously flooded irrigation, AWD). The results showed that AWD didn’t affect rice grain yield in 2016, but reduced it in 2017 without Z application; and rice yield was not affected by AWD with the application of 10 t Z ha−1 in two years, relative to CF. AWD reduced highest and ineffective tiller number in 2016, and highest and final tiller number in 2017; as well as LAI after joint-booting stage, relative to CF. Z amendment significantly increased highest and final tiller number, but didn’t affect ineffective tiller number; and increased LAI after joint-booting stage. The principal components analysis showed that grain yield was more significantly correlated with the panicles per m2, NT, and aboveground DMA and NA after panicle-initiation stage. As compared to CF, AWD significantly reduced aboveground DMA after panicle-initiation stage; aboveground NA after joint-booting stage in both years; and NT in 2016, but not in 2017. Z amendment significantly improved aboveground DMA and NA after tillering stage, as well as NT and panicles per m2. In addition, AWD with Z amendment significantly improved inorganic N content in soil.

Potential nutrient removal function of naturally existed ditches and ponds in paddy regions: Prospect of enhancing water quality by irrigation and drainage management

Conventionally, paddy fields are regarded as important non-point sources of nutrient pollution, while ecological ditches and ponds are developed to reduce or retain nutrient export from agricultural fields. To quantify the potential nutrient removal function of ditches and ponds that naturally existed in rice growing regions, a representative paddy irrigation and drainage unit (IDU) composed of fields, ditches and a pond in the one-season rice region of the middle Changjiang River basin, China was monitored for two years. With data and knowledge gained, a Water Quantity and Quality Model for Paddy IDUs (WQQM-PIDU) is developed and applied for 30 years simulation to produce a general view. The monitored and modelled results showed that nutrient concentration peaks after fertilization was delayed and lowered in ditches and ponds, compared to those in paddy fields. Concentrations of runoff from the IDU outlet were generally lower than from the field during the whole rice growing season except the transplanting period. If fully utilized as temporary reservoirs, ditches and ponds naturally existed in a typical paddy IDU would reduce 39% nitrogen loads from field edges with a range of 17%–93% and 28% phosphorus loads with a range of 12%–92%. Although typical paddy IDUs discharge fewer nutrient loads than the content input into them, the discharge concentrations may be risky to surface waters. For their nutrient removal function, natural ditches and ponds are recommended to be included into irrigation and drainage management with accurate water level management during drainage, which is a promising and cost-effective approach to enhance surface water quality in rice growing regions.

Health risk assessment of Cd pollution in irrigated paddy field system: A field investigation in Hunan Province, China

Paddy crops cadmium (Cd) pollution has received widespread attention. Here, we assessed levels of Cd and organic matter fractions in sediments and paddy system of 19 paddy fields that were located 20 km away from an irrigation water source in central Hunan Province, China, to determine pollution risks of Cd to human health. With the exception of a single study site, levels of Cd in irrigation water met national irrigation water quality standards (GB5084-2005). In contrast, average Cd content in paddy soil and brown rice (0.625 and 0.567 mg kg−1, respectively) was 1.6 and 2.8 times higher than levels permitted by national standards for soils (GB15618-2018) and food safety (GB2762-2017), respectively. Dominant speciated Cd in sediments included extractable, oxidizable, and reducible Cd that accounted for 84.96% of total sediment Cd content. The average carbon content of humus was 18.906 g kg−1. Fulvic acid content of humus was positively correlated with reducible and oxidizable Cd content. Cd pollution in paddy fields was great and risks of Cd in brown rice to human health were high. Risk assessment can provide reasonable suggestions for human diets and provide new ideas for the prevention and control of soil Cd pollution.

Application of a Self-Organizing Map of Isotopic and Chemical Data for the Identification of Groundwater Recharge Sources in Nasunogahara Alluvial Fan, Japan

Paddy rice fields on an alluvial fan not only use groundwater for irrigation but also play an important role as groundwater recharge sources. In this study, we investigated the spatial distribution of isotopic and hydrochemical compositions of groundwater in the Nasunogahara alluvial fan in Japan and applied a self-organizing map (SOM) to characterize the groundwater. The SOM assisted with the hydrochemical and isotopic interpretation of the groundwater in the fan, and clearly classified the groundwater into four groups reflecting the different origins. Two groundwater groups with lower isotopic ratios of water than the mean precipitation values in the fan were influenced by the infiltration of river water flowing from higher areas in the catchments and were differentiated from each other by their Na+ and Cl− concentrations. A groundwater group with higher isotopic ratios was influenced by the infiltration of paddy irrigation water that had experienced evaporative isotopic enrichment. Groundwater in the fourth group, which was distributed in the upstream area of the fan where dairy farms dominated, showed little influence of recharge waters from paddy rice fields. The findings of this study will contribute to proper management of the groundwater resources in the fan.

The impact of nitrogen fertilizer on the aquatic environment in the Upper Tondano watershed, North Sulawesi Province

Nitrogen fertilization is needed as a source of nitrogen in the growing plants. Nitrogen in the environment will undergo a transformation in the form of compounds such as nitrate (NO3−) and nitrite (NO2−). The transformation from nitrogen to nitrate, nitrite, will have a negative impact on the aquatic environment namely the formation of toxic conditions. The main purpose of this research was to study the residual nitrogen fertilizer in the outlet of paddy irrigation upper Tondano Watershed and to evaluate the residual nitrogen fertilizer in the outlet of paddy irrigation upper Tondano Watershed 5-years period (2015-2019). Water quality sampling was carried out using a composite sampling method at two sample locations in River Panasen, in situ measurement of water temperature parameters, and pH. Analysis of the parameters of nitrate and nitrite was carried out in the laboratory. Data were analyzed using descriptive statistics. The results showed that the concentration nitrate of -0.9330-153 mg/l (according Government standard PP No. 82/2001 nitrate 10 mg/l), and nitrite of 0.001 mg/l-0.52 mg/l exceed PP No. 82/2001 quality standard (0.006 mg/l).

Temporal variation of water suitability for paddy irrigation needs at karst springs influenced by allogenic recharge in Gunungsewu Karst Area, Indonesia

Irrigation, a critical element in farming, can fulfill crop water needs and increase agricultural productivity during the dry season, provided that the two necessary factors are met, namely water supply and water quality. Water quality is a principal factor in assessing whether or not a water body is usable as a source of irrigation. Excess or lack of elements in irrigation water may affect irrigated crops and soil. For maximum harvests, studies scrutinizing the suitability of water supply for irrigation become necessary. Beton Spring has a large discharge, which the people of Ponjong District, Gunungkidul Regency, rely on for their irrigation and fish farming practices. Uniquely, this karst spring receives allogenic recharges from outside the karst area. This research was intended to assess the suitability of water quality of Beton Spring for temporal irrigation purposes by Sodium analysis (Na%), Sodium Adsorption Ratio (SAR), USSL, and Wilcox. The elements observed in the analysis were Ca2+, Na+, Mg2+, K+ and electrical conductivity. Based on the overall analysis results of the water quality series—Sodium analysis (the water samples were classified as Excellent), SAR (Excellent), USSL (moderate to good), and Wilcox (Excellent to Good), Beton Spring produces good-quality water that is suitable for irrigation.