Lowland Rice Production Systems Research Articles

A Low-Cost Wireless Sensor for Real-Time Monitoring of Water Level in Lowland Rice Field under Alternate Wetting and Drying Irrigation

The use of wireless sensors for real-time monitoring of field water level would greatly facilitate the application of alternate wetting and drying (AWD), an irrigation water management technique proven to result to significant water savings and reduced methane emissions in lowland rice production systems. However, most of the commercially available wireless sensors are generally costly. This study developed a low-cost wireless sensor that can perform real-time monitoring of water depth and surface temperature in lowland rice fields under an AWD irrigation regime. The sensor is composed mainly of an ultrasonic depth sensor, a waterproof temperature sensor, a humidity sensor, and a Wi-Fi-enabled microcontroller enclosed in a PVC cap that can be mounted in AWD pipes. The sensor was tested under laboratory, pseudo-field conditions and actual field conditions. Results showed a relatively high degree of agreement between sensor and manual measurements of water depth under all testing conditions, with the error ranging from only 5.2% to 6.6% and RMSE of 5.0 mm to 13.5 mm. The performance of the low-cost sensor also proved to be comparable with that of the high-end sensor, exhibiting practically similar measurement accuracy and higher precision. The wireless sensor developed in this study can provide a low-cost alternative to the high-cost and high-end sensors and other commercially available counterparts for efficient irrigation water management in lowland crop production systems during water-scarce conditions induced by climate change and climate variability.

Performance evaluation of a water level sensor under various turbidity levels in lowland crop production systems

The practice of alternate wetting and drying (AWD), a water-saving technology in lowland crop production systems, can be greatly facilitated using wireless water level sensors. However, these sensors generally work under clear water conditions. The sensitivity of these sensors to turbidity is important for accurate water level measurement and appropriate irrigation scheduling. This study evaluated the performance of a high-end water level sensor of the submersible pressure transducer type under various turbidity levels. The performance tests were performed in the laboratory using water samples collected from a typical lowland rice production system under various levels of turbidity replicated three times with clear water as control. The readings of the sensors were compared with manual readings for each turbidity level in all replications. Results showed that the measured water level depth generally increases with increasing turbidity for each voltage level. The linear regression or calibration equation developed for each turbidity level proved to be adequate as evidenced by a relatively low RMSE of less than 1 mV. Results of ANOVA suggest that turbidity significantly affects the accuracy of the water level sensor (p <.001). A unified calibration equation (R2=0.9985 and RMSE=1.971 mV) was developed to account for the effect of turbidity up to 4300 FAU on the water level measurements. Results of this study can be used to improve the accuracy of water level monitoring in irrigated lowland crop production systems employing alternate wetting and drying technology to further increase irrigation efficiencies and augment water savings particularly during the dry season or under water-scarce conditions for a more sustainable crop production.

A coupled surface-subsurface flow model for simulating soil-water dynamics in lowland rice field under alternate wetting and drying conditions

The lack of coupled surface-subsurface flow models applied in lowland rice irrigation systems is the prime mover for this research. This study aimed to develop a coupled model that can capture the soil-water dynamics in paddy rice fields and to calibrate and validate the model using actual field data to serve as basis for irrigation water management using alternate wetting and drying (AWD) for lowland rice production systems. The zero-inertia surface flow model was internally coupled with the Richards-based subsurface flow model through Python scripts. Boundary conditions were set accordingly based on lowland rice field scenarios. Irrigation advance times were observed manually, while field water recession data were collected using wireless sensors. Model calibration showed acceptable results for the surface flow (R2≥0.99; SE≥0.97; RMSE≤3.14min), and subsurface flow (R2≥0.71; NSE≥0.60; MSE≤8.78mm; SD≤5.51mm; AE≤7.51mm) domains. Likewise, model validation yielded acceptable results for surface flow (R2≥0.98; NSE≥0.88; RMSE≤6.12min) and subsurface flow (R2≥0.76; NSE≥0.60; RMSE≤10.87mm; SD≤7.91mm; AE≤8.28mm), respectively. Results also showed the model’s capability to simulate water level fluctuations in AWD-irrigated rice fields during the wet and dry seasons under various rainfall scenarios. Model projections showed the need for AWD irrigation practice when the normal rainfall had been reduced by 75% during the wet season. Dry season simulations indicated the need for AWD under all rainfall scenarios. Simulation results have further unveiled the importance of the plow pan characteristics in influencing the soil-water flow behavior. This study was also able to address the limitations of the existing coupled models that could not meet the boundary conditions of paddy rice field settings. Ultimately, the model developed in this study could serve as basis for the development of optimum irrigation operation schemes in AWD -irrigated rice fields.

Comparative analysis of the profitability of rice production systems in Kwara State, Nigeria

&#x0D; &#x0D; &#x0D; This study describes the socioeconomic characteristics of rice farmers, identifies the production system used by the farmers, compares the profitability of rice production systems, identifies the factors influencing the choice of production systems among the farmers as well as the constraints to rice production systems. A three-stage random sampling procedure was used to select 120 rice farmers on whom a set structured questionnaire was administered. Data was analysed using descriptive statistics and multinomial logistic regression model. Results show that 48.3%, 35% and 16.7% of the farmers cultivate rice using the upland, lowland and the combined production systems respectively. The findings also reveal variability in yield, profit and income across the rice production systems. The gross margins for lowland, upland and combined rice production systems were N65,735.73, N67,900.89 and N78,015.57 per hectare respectively. The factors that influenced the choice of upland production system relative to combined production system were age, household size, farming years and extension visits while the factors that influenced the choice for combined rice production system relative to lowland rice production system was income. Inadequate finance to purchase inputs, problem of pests and diseases, and unfavorable climatic conditions are the constraints faced by rice farmers in the upland, lowland and combined production systems. The combined production systems had the highest return per hectare. Therefore, the study recommends that farmers should be encouraged to choose the combined rice production system for optimum profitability of rice production.&#x0D; &#x0D; &#x0D;

Transplanting as an option to cope with abiotic stress in high‐altitude lowland rice production systems in East Africa

AbstractThe current practice of direct seeding in East‐African high‐altitude rice farming systems is constrained by water availability early in the season and low temperatures later in the season at the crop's critical reproductive stage. Thus, productivity is restricted as only short‐duration varieties can be grown due to the risk of crop failure. To fully exploit the yield potential of such rainfed systems, the best combination of crop establishment methods and climatic ‘best fit’ genotypes is required. In this study, nine rice genotypes were evaluated under direct seeding and transplanting in the 2016 and 2017 cropping seasons with the aim of identifying genotype by environment by management combinations best fitting the high‐altitude, rainfed rice production systems. On average across all genotypes, transplanting had a positive yield effect of 18% in 2016 and 23% in 2017. Regarding the phenological development, individual phenophases were not significantly affected by transplanting relative to direct seeding; however, vegetative development stages in transplanted rice tended to be about 15% longer than when direct seeded. Even though transplanting led to extended vegetative growth, the time in the nursery allowed the plants to escape the cold spell late in the season. The results from the current study provide options to adapt cropping calendars by combining genetic resources with targeted crop management, thus improving and stabilizing yields of rainfed lowland rice farming systems at high altitude.

Valuation of External Costs of Wet-Season Lowland Rice Production Systems in Northern Thailand

This study aims to assess the external costs of environmental impacts associated with the rice production systems using LCA approach and evaluated them into the economic value. The study compared the different chemical and energy use, as well as straw management of the three different rice production systems, included the mainstream conventional rice system, GAP rice system, and the organic rice system in Northern Thailand. The LCA analysis quantified the midpoint and endpoint of five environmental impacts, including climate change, terrestrial acidification, eutrophication, water depletion, and human health damage, from cradle-to-farm gate. The results of economic valuation revealed that the external costs of the conventional and GAP rice systems have significantly higher than that of the organic system. Most external costs came from the wastewater treatment cost due to the eutrophication mainly arising from the use of chemical fertilizer. Besides, about one-fourth of the total external costs came from the human health damage cost due to the open-air rice straw burning. To reduce the external costs of rice production, the amount of chemical fertilizer use causing eutrophication should be diminished and replaced by applying organic fertilizer from incorporating rice straw into the soil as well as growing a rotational crop after rice cultivation to stop the open-air rice straw burning and reduced the human health damage. The government should encourage rice farmers to the organic rice farming and manage the rice straw without burning because they may have the cost burden, whereas society gains more benefits from less pollution. Keywords: Economic valuation, Environmental impacts, Life Cycle Assessment, Rice production systems, Thai Good Agricultural Practice

Long-Term Effect of Various Organic and Inorganic Nutrient Sources on Rice Yield and Soil Quality in West Coast India Using Suitable Indexing Techniques

ABSTRACT Soil quality (SQ) under any agriculture system is greatly influenced by source of nutrients, type of soil, crop, and their management practices. In this regard, a field experiment was conducted under lowland rice production system for 5 years to assess the effect of nutrient management with organic and inorganic nutrient on soil quality. The nutrient management practices studied were: FYM: farmyard manure (10 t ha−1), Verm: vermicompost (5 t ha−1), GE: Gliricidia and Eupatorium (each 5 t ha−1), PW: Paddy straw and water hyacinth (each 5 t ha−1), SR: Dhaincha (10 t ha−1), RDF-NPK: recommended dose of fertilizers (100:50:50 NPK kg ha−1), and control. The effect of different nutrient management practices on the soil properties, grain yield, sustainable yield index, and soil quality index were evaluated. The nutrient management practices affected the soil properties, rice grain yield, and sustainable yield index significantly. Phosphatase activity, soil organic carbon, microbial biomass carbon, available phosphorus, and nitrogen were selected for minimum data set using principal component analysis. Their corresponding average contribution to the soil quality index was 70.7, 7.92, 8.67, 1.69, and 10.9%, respectively. The soil quality index obtained by integrating the minimum data set and employing non-linear scoring function varied from 0.72 (SR) to 0.99 (FYM) and it was minimum in the control (0.68). The FYM improved the SQ by 28.5 and 45.5% over RDF-NPK and control, respectively. Using organic sources of nutrients under transplanted rice improves the soil quality and sustainability by improving plant growth and soil functions.

Optimization of Nitrogen Fertilizer Application in Lowland Rice Production System of Agricultural Resource System Research Station Using Tailored Farm-plot Database

Optimization of Nitrogen Fertilizer Application in Lowland Rice Production System of Agricultural Resource System Research Station Using Tailored Farm-plot Database

Title: Assessment on Constraints and Opportunities of Rice Production Trends in Fogera - Ethiopia. The Case of Lowland Rice Production System

Title: Assessment on Constraints and Opportunities of Rice Production Trends in Fogera - Ethiopia. The Case of Lowland Rice Production System

Effect of Water and Rice Straw Management Practices on Soil Organic Carbon Stocks in a Double-Cropped Paddy Field

ABSTRACTWater and rice straw (RS) management practices can potentially affect the accumulation of soil organic carbon (SOC) in agricultural soils. Field experiments were conducted in two consecutive rice-growing seasons (wet and dry) to evaluate SOC stocks under different water (continuous flooding [CF], alternate wetting and drying [AWD]) and RS management practices (RS incorporation [RS-I], RS burning [RS-B], without RS incorporation and burning [WRS]) in a double-cropped paddy field. RS-I under AWD had higher volumetric water content than the same RS management under CF at tillering in both growing seasons. Total SOC was significantly higher under AWD at tillering in both wet and dry seasons and after harvesting in the dry season compared with CF. The same trend was also observed for C:N ratio at tillering and after harvesting in the dry season. RS-B plots had lower SOC stocks than RS-I and WRS plots across most of the measuring periods regardless of the growing seasons. SOC stocks were 33.09 and 39.31 Mg/ha at RS-B and RS-I plots, respectively, in the wet season, whereas the respective values were 21.45 and 24.55 Mg/ha in the dry season. Incorporation of RS enhanced SOC stocks under AWD irrigation, especially in the dry season before planting. Soil incorporation of RS in combination with AWD could be a viable option to increase SOC stocks in the double-cropped rice production region as it is strongly linked with soil fertility and productivity. However, the environmental consequences of RS incorporation in irrigated lowland rice production system should be taken into consideration before its recommendation for paddy field on a large scale.

High-Throughput Biomass Estimation in Rice Crops Using UAV Multispectral Imagery

This paper presents a high-throughput method for Above Ground Estimation of Biomass (AGBE) in rice using multispectral near-infrared (NIR) imagery captured at different scales of the crop. By developing an integrated aerial crop monitoring solution using an Unmanned Aerial Vehicle (UAV), our approach calculates 7 vegetation indices that are combined in the form of multivariable regressions depending on the stage of rice growth: vegetative, reproductive or ripening. We model the relationship of these vegetation indices to estimate the biomass of a certain crop area. The methods are calibrated by using a minimum sampling area of 1 linear meter of the crop. Comprehensive experimental tests have been carried out over two different rice varieties under upland and lowland rice production systems. Results show that the proposed approach is able to estimate the biomass of large areas of the crop with an average correlation of 0.76 compared with the traditional manual destructive method. To our knowledge, this is the first work that uses a small sampling area of 1 linear meter to calibrate and validate NIR image-based estimations of biomass in rice crops.

Growth, yield and water productivity of selected lowland Thai rice varieties under different cultivation methods and alternate wetting and drying irrigation

Development of water‐saving techniques for irrigated lowland rice production system is a requirement in the context of increasing irrigation water scarcity. A pot experiment was conducted to evaluate the performance of selected lowland Thai rice varieties grown under different cultivation methods subjected to alternate wetting and drying (AWD) irrigation. Treatments consisted of three varieties (Pathumthani 1, RD57 and RD41), three cultivation methods (dry direct seeding [DDS], wet direct seeding [WDS] and transplanting [TP]) and four AWD irrigation levels (re‐watered when soil water potential reached at 0, −5, −15 and −30 kPa). DDS resulted in higher grain yield at −5 and −15 kPa (74 and 68 g/pot, respectively) with a respective reduction of 15 and 34% under WDS and TP at −5 kPa, and 15 and 28% at −15 kPa. The highest water productivity was recorded at −30 kPa under DDS, which was reduced by 17–61% for other soil water potentials irrespective of varieties; however, grain yield was also reduced by 12–19% at −30 kPa. All varieties responded similarly to water‐saving techniques (direct seeding and different levels of AWD) with non‐significant differences in grain yield and water productivity; therefore, could be recommended to grow these varieties using water‐saving techniques. The optimum threshold level of AWD could be −15 kPa for its high grain yield and water productivity.

Effect of Simulated Flooding and Nitrogen Application on Nitrogen Uptake of Rice

In lowland rice production systems, flooding patterns vary during the cropping period and this poses a serious challenge to productivity due to the effect of flooding on the availability and uptake of nitrogen. The aim of this study was to examine the influence of various flooding patterns on nitrogen use in rice grown under simulated wetland conditions. Rice was grown in a greenhouse at 0, 110 and 220 kg N ha-1 under well watered control conditions, continuous flooding, early flooding at tillering, and late flooding post-tillering. The results showed that continuous and early flooding increased tiller production and grain yield compared to late flooding or non-flooded conditions. Although the highest grain yields under the different flooding patterns were obtained with 220 kg N ha-1, the combination of 110 kg N ha-1 and early flooding also significantly increased tiller productivity, nitrogen recovery, and agronomic nitrogen use efficiency (NUE). There is the need to regulate the supply of nitrogen and water resources if grain yield and NUE has to be increased at minimal costs. Also, compared to well-watered conditions, rice production under flooded conditions lead to increased productivity and N rate must match realistic target yields. Best results are obtained when flooding occurs in the early rather than later parts of the season.Bangladesh Agron. J. 2017, 20(1): 67-75

The Influence of Zeolite Amendment on Yield Performance, Quality Characteristics, and Nitrogen Use Efficiency of Paddy Rice

The yield and environmental benefits of zeolite (Z) applied to agriculture are clear in many different types of soil for upland crops. However, limited information is available for lowland rice (Oryza sativa L.) production systems. A 2‐yr field experiment using a strip‐plot design was conducted to evaluate the impact of Z amendment on yield performance, quality characteristics, and nitrogen (N) use efficiency of paddy rice. Japonica rice (cv. Gangyu 6) was cultivated in a silty loam soil with N application (0, 52.5, 105.0, and 157.5 kg N ha−1) as whole plots and Z amendment (0, 5, 10, and 15 t Z ha−1) as strip plots. Compared with the paddy field without Z amendment, there was 14.2 to 35.8% higher potential postharvest residual soil mineral N and 20.1 to 44.6% higher exchangeable potassium when the upper 30 cm of the soil was amended with 5 to 15 t Z ha−1. Application of 5 to 15 t Z ha−1 increased applied N fertilizer use efficiency by 39.0 to 64.4% and N recovery efficiency by 20.7 to 85.2%, respectively. Milling, appearance, and eating quality traits were not affected by Z amendment, whereas rice protein content was increased by Z addition. The enhanced yield performance due to Z was mainly caused by improved essential plant‐available nutrients, which reduced ineffective tillers and produced more effective tiller number per square meter at harvest. In addition, these positive residual activities were maintained for at least an additional year after initial application in the lowland rice production system.

Padi Aerob Untuk Mengatasi Masalah Kekurangan Air

Irrigated lowland rice is the most important rice ecosystem in Malaysia. The present and future food security in rice for the country depends largely on the irrigated lowland rice production system which consumes a large amount of water. Signs of declining water availability due to increased demand of water for domestic and industrial uses besides irregularity of rainfall and climate change threatens the sustainability of irrigated rice production. This scenario may change the way rice is produced in the future. Aerobic rice is a potential water saving rice production system and will be the best option of producing rice in water scarce environment. The availability of aerobic rice varieties that can withstand aerobic condition, responds to irrigation and fertilizers, competitive against weeds and deliver a high yield is crucial to make aerobic rice cultivation successful. Since weeds are major constraints to aerobic rice, it must be effectively controlled through integrated weed management. Appropriate nutrient and other crop management practices will ensure successful aerobic rice production system.

Participatory evaluation of mechanical weeders in lowland rice production systems in Benin

Weeds are a major constraint to rice (Oryza sativa) production in sub-Saharan Africa. Use of mechanical hand weeders could reduce the labor required for weeding. This paper uses a participatory approach to examine the suitability of six mechanical weeders in Benin. A total of 157 farmers (93 male, 64 female) in 14 villages tested the mechanical weeders, ranked them in order of preference, and compared them with their own weed management practices. The ring hoe had the highest rank, followed by the straight-spike weeder; 97% of the farmers preferred the ring hoe to their own weed management practices, by hand or using traditional hoe, because of its easy operation and high efficiency. The ring hoe tended to be preferred especially in the fields with non-ponded water and relatively higher weed pressure. The straight-spike weeder tended to be preferred to ring hoe in the fields where weed pressure is less, whereas in ponded conditions, farmers liked these two weeders in equal proportion. The preference of weeders was not related to gender, rice field size, or years of experience of rice cultivation. Among 23 farmers who used herbicides, 17 farmers preferred herbicides to the ring hoe and have rice field of >0.5 ha. Mechanical weeders can offer an effective approach for weed management, especially for small-scale rice farmers, and different types of mechanical weeders should be introduced to farmers based on water regimes and weed pressure level.

Effects of Farmyard Manure and Inorganic Fertilizer Application on Soil Physico-Chemical Properties and Nutrient Balance in Rain-Fed Lowland Rice Ecosystem

A field experiment was conducted to assess the effects of combined application of farm yard manure (FYM) and inorganic NP fertilizers on soil physico-chemical properties and nutrient balance in a rain-fed lowland rice production system in Fogera plain, northwestern Ethiopia. The study was carried out during the main cropping seasons of 2010 and 2011. Twenty-seven treatments comprising a factorial combination of three rates of FYM (0, 7.5, and 15 t·ha-1), three rates of nitrogen (0, 60, 120 kg·N·ha-1) and three rates of phosphorus (0, 50 and 100 kg·P2O5·ha-1) were tested. The experiments were laid out as a randomized complete block design with three replications. Bulk density, organic matter content, and available water holding capacity, total N, and available P of the soil were measured just after harvesting the rice crop. Results showed that application of 15 t·FYM·ha-1 significantly increased soil organic matter and available water holding capacity but decreased the soil bulk density, creating a good soil condition for enhanced growth of the rice crop. Application of 15 tFYM·ha-1 increased the level of soil total nitrogen from 0.203% to 0.349%. Combined application of 15 t·ha-1·FYM and 100 kg·P2O5·ha-1 increased the available phosphorous from 11.9 ppm to 38.1 ppm. Positive balances of soil N and P resulted from combined application of FYM and inorganic N and P sources. Application of 15·t ha-1·FYM and 120 kg·N·ha-1resulted in 214.8 kg·ha-1·N positive balance while application of 15 t·ha-1·FYM and 100 kg·P2O5·ha-1 resulted in a positive balance of 69.3 kg·P2O5·ha-1 available P. From the results of this experiment, it could be concluded that combined application of FYM and inorganic N and P fertilizers improved the chemical and physical properties, which may lead to enhanced and sustainable production of rice in the study area.

Determinants of total factor productivity in rain-fed lowland rice production system in Nigeria

Nigeria ranks highest as both producer and consumer of rice in the West African sub-region and has a very high potential of becoming a major producer and exporter of rice in the region, yet the country currently is not able to meet up with the domestic rice demand. Rain-fed upland and lowland ecologies constitute 80-85% of the national cultivated rice land and contribute 73-80% of total rice production. These two rice ecologies are noted to have the potential to meet national rice demand. This study examines the determinants of total factor productivity in the rain-fed lowland rice production system. Through a multi-stage sampling technique, a total of 151 rice farmers were selected and data collected through structured questionnaire. Results indicate significant positive effects of extension visits, commercialization level, farming experience and family labour on total factor productivity. Appropriate programs and policies in relation to these factors could further enhance productivity towards meeting the national demand for rice.

SRI as a methodology for raising crop and water productivity: productive adaptations in rice agronomy and irrigation water management

The System of Rice Intensification (SRI), developed in Madagascar almost 30 years ago, modifies certain practices for managing plants, soil, water, and nutrients with the effect of raising the productivity of the land, labor, and capital devoted to rice production. Certain production inputs are reduced—seeds, inorganic fertilizer, water, and fuel where water is pumped—with increased yield as a result. This paper introduces the subject of SRI, which is then addressed variously in the articles that follow. SRI is gaining interest and application in over 40 countries around the world. Its practices make soil conditions more aerobic and promote greater root growth, as well as larger, more diverse communities of beneficial soil biota. These below-ground changes support more productive phenotypes above-ground for practically all rice genotypes (cultivars) tested so far, with supportive evidence accumulating both from scientific institutions and field applications. SRI methodology remains controversial in some circles, however, because of the transformational change it introductions into traditional lowland rice production systems. This issue of PAWE brings together the results of formal research on SRI in a number of countries (Part I) and also reports on initiatives by government agencies, NGOs, universities, or the private sector, bringing knowledge of SRI to farmers in a wide range of agroecological circumstances (Part II). This introduction presents the basic principles that underlie SRI and discusses the nature of this innovation as well as considers some of the issues in contention. SRI continues to evolve and expand, being a work in progress. Its concepts and methods are being extended also to upland (rainfed) rice production, as well to other crops. Accordingly, SRI should not be regarded or evaluated in conventional terms as if it were a typical component technology. It is understood more appropriately in terms of a paradigm shift for rice production. In particular, it calls into question the long-standing belief that rice is best produced under continuously flooded conditions.

Yield, water and nitrogen-use response of rice to zeolite and nitrogen fertilization in a semi-arid environment

Abstract Water scarcity and soil nitrogen (N) loss are important limitations for agricultural production in semi-arid region especially for rice production. Zeolite (Z) as a soil conditioner can be used to retrain water and nitrogen in near-surface soil layer in lowland rice production system. The objectives of this study were to investigate the effects of different application rates of natural zeolite (clinoptilolite) and nitrogen on rice yield, yield components, soil nitrogen, water use, water productivity in a silty clay soil in 2004 and 2005. Zeolite was only applied in the first year. In order to study the long-term and continuous effect of zeolite on the objectives of the study, no zeolite was applied in the second year and the study was conducted on the same land as the first year. Zeolite and N were applied at rates of 0, 2, 4, and 8 t ha−1 and 0, 20, 40, and 80 kg ha−1, respectively in 2004. In 2005, each plot received the same amount of N as received in 2004. It is concluded that by decreasing N application rates, higher Z application rate is needed to improve grain yield. Highest grain yield was obtained at N application rate of 80 kg ha−1 and Z application rate of 4 t ha−1. Higher grain yield was mostly attributed to lower unfilled grain percentage and higher 1000-grain weight that were a result of higher N application rate and N retention in soil due to Z application. Nitrogen and Z applications resulted in higher grain protein contents and nitrogen recovery efficiency (NRE). Based on these results and due to higher N retention in soil under Z application, improved grain yield quality, nitrogen-use efficiency ( NUE) , and nitrogen recovery efficiency (NRE) could be obtained at Z application rate of 8 t ha−1 and N application rate of 80 kg ha−1 or more. However, this was not satisfied for NUE. Moreover, it is found that at higher N application rates lower Z application rates are needed to effectively retain soil residual mineral nitrogen. Furthermore, at N application rates of 80 kg ha−1 or more, Z application increased soil water retention and resulted in lower seasonal water use and higher water productivity. In general, it was concluded that the effect of Z application in retaining soil N was also effective in the second year.