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1.
In the Hetao Irrigation Districts of the Ningxia autonomous region, Upper Yellow River Basin, the continuous deep flooding irrigation method is used for the rice paddies. The field irrigation water use during the rice-growing season is two to three times higher than in other regions of North China where water-saving practices have been introduced. This paper, based on the data measured in experimental rice fields and sub-branch canal systems, presents main results concerning crop evapotranspiration, percolation and irrigation requirements for deep and shallow water irrigation. Causes for water waste relate to both the lack of regulation in supply and distribution canals and to the poor management of paddy fields. The potential for water saving is discussed using water balance data. Improved irrigation techniques and water management strategies, including the shallow water irrigation method, are suggested considering the expected impacts and benefits. Replacing the current continuous deep flooding with the shallow-ponded water irrigation method may reduce the growing season irrigation water use from 1,405 to 820 mm in average, with a likely increase in yields of 450 kg/ha. Water productivity would then increase from 0.49 to 1.03 kg/m3. Adopting improved canal management and modernization of regulation and control structures may lead to decreasing the gross irrigation demand from the present 3,100 mm to about 1,280 mm, which would highly benefit the environmental conditions in the area.  相似文献   

2.

In the last 40 years, the rice-cropping system has considerably changed in the Ayeyarwady Delta. The large archive of satellite imagery provides a history of how land and water resource managements have changed in the face of growing populations, resource demand, and climate change. This study aimed to assess the decadal changes in the rice-cropping system in the Ayeyarwady Delta by using the large archive of satellite imagery for the last 40 years (1981???2020). The long-term NDVI dataset provided various information on rice cultivation. Signal processing techniques were used to detect on the historical changes in the rice-cropping system, and the impact of climate change was assessed by using trend analysis. Until the 1980s, single-cropping of summer rice was dominant in the Delta. To enhance the grain yield of rice, the irrigation facilities were introduced in 1992 under an initiative of the Myanmar government. As a result, the annual cropping intensities increased from 1.087?±?0.390 in the 1980s to 1.422?±?0.499 in the 2010s. The information on historical change in the rice-cropping system would be useful to consider the practical and cost-effective utilization of remaining land and water resources. Moreover, the trend analysis of NDVI time-series showed negative trends in coastal areas. This indicates that the rice production in coastal areas has been constrained by the saline intrusion. The salt-affected areas are expected to expand under future climate change scenarios. Government support is highly required for sustainable rice production in the Delta.

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3.
As opportunities to enhance the irrigation base for raising food production in the country are dwindling, India needs a more concerted effort to increase the efficiency and productivity of its irrigation systems. This study, based on an analysis of experience from the state of Andhra Pradesh, addresses the potential of the System of Rice Intensification (SRI) to contribute to systemic corrections in present paddy cultivation, both with regard to agronomic productivity and irrigation water use efficiency. This study points to the considerable increase in rice productivity and farmer incomes, which is being achieved in Andhra Pradesh with substantial reduction in irrigation water application, labor, and seed costs through utilization of SRI methods. Potential public savings on water and power costs could be drawn upon not only for promoting SRI but also to effect systemic corrections in the irrigation sector, to mutual advantage.  相似文献   

4.
In the large-scale irrigation schemes of the lower Ili River Basin of Kazakhstan, crop rotation combines paddy rice and non-rice crops. Continuous irrigation is practiced in paddy fields, whereas other crops are sustained from groundwater after only limited early irrigation. The water table in non-rice crops is raised by seepage from canals and the flooded paddy fields. We investigated the areal extent to which the groundwater level of non-irrigated fields is influenced by seepage from canals and paddy fields by examining the relationship between distance (from canal and paddy field) and groundwater level in upland fields. The groundwater level was influenced for up to 300 and 400 m from the canals and paddy fields, respectively. Geographic information system analysis of crop and canal patterns in the 11 selected years showed that if the zone of influence is 300 and 400 m from the canals and paddy fields, respectively, the groundwater level of most of the area of upland fields was raised by seepage. We conclude that the water supply to cropping fields by seepage from irrigation canals and paddy fields is adequate, but the spatial distribution of the paddy fields may be an important factor that needs more attention to help improve water use efficiency in this irrigation district.  相似文献   

5.
宋代的水稻生产   总被引:1,自引:0,他引:1  
宋代(公元10~13世纪)是中国科学技术高度发展的朝代,在中国科学技术史上占有突出的地位。无论是天文、数学、地学、兵器、造船、印刷术、医药、建筑、纺织、冶金、瓷器等领域或行业,都有可观的成就。农业生产也不例外,特别是水稻的生产(以及蚕桑)在中国历史上第一次超过北方的粟麦,使水稻的生产从此更为巩固和进一步得以发展。介绍了宋代水稻的生产状况。  相似文献   

6.
The center of Jilin Province is one of the major rice-producing areas of Northeast China; however, rice production consumes large amounts of water, which is incompatible with the increasingly limited water supply. Rice yield and water consumption are the two most important considerations in the rice production process, and they may vary under different irrigation schedules. In this study, conducted in 2011 and 2012, differences in water consumption and rice yield were observed and analyzed under four different irrigation schedules—flooding irrigation (FI), shallow-wet irrigation (SWI), intermittent irrigation (II), and controlled irrigation (CI)—in a typical rice-growing area of central Jilin. The results showed that, under the four irrigation schedules, water consumption rates were (from highest to lowest) FI (1137.9 mm), SWI (984.0 mm), II (804.3 mm), and CI (678.5 mm), and rice yield rates were (from highest to lowest) SWI (9777.5 kg/ha), FI (9006.1 kg/ha), II (8936.3 kg/ha), and CI (8843.7 kg/ha), respectively. This indicated that, in central Jilin Province, the application of an advanced irrigation schedule not only saved a large amount of water for irrigation, but also that rice yields were not greatly reduced, and even increased in SWI. Therefore, we hope that in this and other similar rice cultivation areas, a universal high-yield and water-saving irrigation schedule can effectively reduce the problem of agricultural water use.  相似文献   

7.
稻草基质育秧不同水分管理对水稻秧苗生长的影响   总被引:1,自引:0,他引:1  
为了明确代土基质培育水稻机插壮秧的水分管理模式,以中嘉早17为试验材料,采取早稻稻草基质育秧,探讨3种水分管理方式(每隔1 d、3 d、5 d灌水1次致基质呈饱和状态)对水稻秧苗生长的影响。结果表明,不同水分管理方式对秧苗素质有明显的影响。适宜的水分亏缺能抑制苗高,促进秧苗根系生长及提高根系的活力,提高成秧率。秧苗2~3叶期对水分亏缺敏感;水分亏缺使秧苗出叶缓慢,叶片长度及鞘长度变短,叶色变淡,对秧苗生长有抑制作用。适宜的水分增强C、N代谢,增加秧苗的干物质量,提高壮苗指数。稻草基质育秧以3 d(W2处理)左右灌水1次的处理有利提高秧苗综合素质,是适于培育水稻机插壮秧的水分管理方式。  相似文献   

8.
In Taiwan, Camellia seed meal is often sprayed on rice paddies during rice transplantation season to stop the growth of Pomacea canaliculata. However, the application of camellia seed meal endangers muciferous mollusks and fishes in paddy fields. Though researchers have examined the effects of the saponin in the camellia seed meal on Pomacea canaliculata, previous studies ignore the effects of saponin on fish. Loaches often inhabit the rivers, lakes, ponds, paddy fields, and canals of low elevation where there have muddy layer with plant chips. This study uses vanillin-sulfuric acid method and field tests on loaches in paddy fields to determine the duration of camellia seed meal’s effect on loaches (Misgurnue Angullicaudatus). Results indicated that the best application to stop the growth of Pomacea canaliculata is to seal the rice field immediately after transplantation, apply the camellia seed meal, and then irrigate the field 2?days after camellia seed meal application for the summer transplantation, and 3?days for the spring transplantation. Water should not be drained from the paddy field after the application of camellia seed meal to reduce the chance of endangering loaches in irrigation canals. Field Tests show that high water temperature during summer also has a negative effect on loaches in paddy fields and irrigation canals.  相似文献   

9.
Concentrations of several pesticides were monitored in a paddy block and in the Kose river, which drains a paddy catchment in Fukuoka prefecture, Japan. Detailed water management in the block was also monitored to evaluate its effect on the pesticide contamination. The concentrations of applied pesticides in both block irrigation channel and drainage canal increased to tens of μg/L shortly after their applications. The increase in pesticide concentrations was well correlated with the open of irrigation and drainage gates in the pesticide-applied paddy plots only 1–3 days after pesticide application. High concentration of other pesticides, mainly herbicides, was also observed in the inflow irrigation and drainage waters, confirming the popularity of early irrigation and drainage after pesticide application in the area. The requirement of holding water after pesticide application (as a best management practice) issued by the authority was thus not properly followed. In a larger scale of the paddy catchment, the concentration of pesticides also increased significantly to several μg/L in the water of the Kose river shortly after the start of the pesticide application period either in downstream or mid–upstream areas, confirming the effect of current water management to the water quality. More extension and enforcement on water management should be done in order to control pesticide pollution from rice cultivation in Japan.  相似文献   

10.
《Plant Production Science》2013,16(5):592-600
Abstract

This research was conducted to determine the yield and water-use efficiency of maize under fixed and variable alternate furrow irrigation (fixed AFI, variable AFI) and every furrow irrigation (EFI) at different irrigation intervals in areas with shallow and deep groundwater. In variable AFI, water was applied to the furrow, which was dry in the previous irrigation cycle. The results indicated that even at 4-day irrigation intervals the water needs of maize on a fine textured soil in both areas (with deep and shallow water table) are not met by AFI. The decrease in grain yield due to water stress was mainly due to the decrease in the number of grains per cob and to a lesser extent to the decrease in 1000-grain weight. At the Kooshkak site with shallow groundwater (between 1.31 and 1.67 m), grain yields in AFI at 4- and 7-day intervals were comparable to those obtained in EFI at 7- and 10-day intervals, respectively. This might be due to the contribution of groundwater to the water use of the plant (about 5-10%). In the Badjgah area, with deep water depth, grain yield in AFI at 7-day intervals was statistically lower than that obtained in EFI at 10-day interval. In AFI, a shorter irrigation interval (4-day) may alleviate the water stress and result in no yield reduction compared with that in EFI at 7-day intervals even though water application was reduced. Furthermore, in the area with a shallow water table, AFI at 7-day intervals may be superior to EFI at 10-day irrigation intervals. When seasonal irrigation water is less than 700 mm, it may be preferable to use AFI at 10-day intervals to increase water-use efficiency, especially in areas with shallow groundwater. In general, when water was insufficient for full irrigation, the relative grain yield (yield per unit water applied) of maize under AFI was higher than those under EFI.  相似文献   

11.
根据水稻不同生育时期采取不同的灌溉方法,即:插秧至返青阶段有水不淹心;返青至分蘖高峰期寸水不露泥;拔节孕穗至蜡熟末期间歇灌溉,缺水补水。结果表明:采用节水灌溉模式稻田可节水1800m^3/hm^2,可增产625.5kg/hm^2,纯增收1431元/hm^2。  相似文献   

12.
根据水稻不同生育时期采取不同的灌溉方法,即:插秧至返青阶段有水不淹心;返青至分蘖高峰期寸水不露泥;拔节孕穗至蜡熟末期间歇灌溉,缺水补水。结果表明:采用节水灌溉模式稻田可节水1800m3/hm2,可增产625.5kg/hm2,纯增收1431元/hm2。  相似文献   

13.
在高海拔寒冷稻作区,通过晒水池增温进行温水灌溉和垄作栽培提高土壤温度。垄作栽培、温水灌溉在移栽后到有效分蘖临界叶龄期的土壤日平均温差分别比常规栽培(对照)高2.94℃和0.57℃。通过调查有效分蘖临界叶龄期水稻的分蘖发生数量和质量,探讨增加土壤温度对水稻分蘖发生和产量及其构成因素的影响。结果表明,丽粳10号垄作栽培、温水灌溉成穗率比对照分别高14.59和0.14个百分点,大白谷分别高12.08和2.09个百分点。丽粳10号垄作栽培、温水灌溉的产量分别比对照高13.79%和10.82%,大白谷分别高13.35%和11.54%。土壤增温可促进高寒生态区水稻早发和干物质积累,增加有效分蘖,优化群体质量,提高成穗率和产量。  相似文献   

14.
This research is to construct a water balance model to estimate the amount of return flow in an irrigation system. A simple computation framework for the model was established to include various irrigation applications in cropping seasons. The model was able to estimate evapotranspiration, deep percolation into groundwater aquifer, and return flow. Return flow can be split into two parts, which are surface and subsurface return flows. The water balance model was then applied at the irrigation system (rotational block No. 11-2 of five paddy field units) which is operated by the Taoyuan Irrigation Association in Taiwan as an example. Two study cases were simulated, in which one was for using return flow and the other one was for using no return flow. The study period for the model simulations is the first rice cropping term in 2010 which was from February 16 to July 10. As a result, return flows calculated by the model were 27, 27, 34, and 39% of outflows for sandy loam, sandy clay, clay loam, and light clay soil, respectively. Irrigation water at the downstream field unit with use of return flow was supplemented by the upstream field units, and the amount is 5?C8% of irrigation water for using no return flow. Furthermore, it can be seen from the simulations that increases in irrigation water provide increases of return flow. Increases of irrigation water result in slight increases of subsurface return flow, while increases of irrigation water cause nearly none of change in deep percolation.  相似文献   

15.
水稻低碳生产研究进展   总被引:11,自引:0,他引:11  
 稻田是甲烷(methane,CH4)和氧化亚氮(nitrous oxide,N2O)的重要发生源。稻田中CH4和N2O的产生、消耗以及传输过程受稻田土壤类型、水分条件、肥料种类、施肥量及方法、耕作模式和制度、水稻品种等多种因素影响。CH4和N2O具有不同的排放特性,很多研究结果表明,水稻生长期间的中期排水烤田、后期干湿交替能显著降低CH4排放量,但同时也可能促进N2O的排放,因此,如何同时减少CH4和N2O的排放量是实现稻田低碳生产的关键要素;另一方面,稻田土壤的碳固定也是使稻田系统从源转变成汇的关键技术。从水稻生产过程中CH4排放、N2O排放、稻田土壤有机碳动态、减排措施四个方面综述了近年来水稻低碳生产相关研究状况,重点总结了国内外有关影响稻田CH4和N2O排放的关键影响因素、增加稻田土壤有机质含量的主要措施以及各种减排措施的全球增温潜势评价研究,并对水稻低碳生产研究作了展望。  相似文献   

16.
Increasing water scarcity has necessitated the development of irrigated rice systems that require less water than the traditional flooded rice. The cultivation of aerobic rice is an effort to save water in response to growing worldwide water scarcity with the pressure to reduce water use and increase water productivity. An accurate estimation of different water balance components at the aerobic rice fields is essential to achieve effective use of limited water supplies. Some field water balance components, such as percolation, capillary rise and evapotranspiration, can not be easily measured; therefore a soil water balance model is required to develop and to test water management strategies. This paper presents results of a study to quantify time varying water balance under a critical soil water tension based irrigation criteria for the cultivation of non-ponded “aerobic rice” fields along the lower parts of the Yellow River. Based on the analysis and integration of existing field information on the hydrologic processes in an aerobic rice field, this paper outlines the general components of the water balance using a conceptual model approach. The time varying water balance is then analyzed using the feedback relations among the hydrologic processes in a commercial dynamic modeling environment, Vensim. The model simulates various water balance components such as actual evapotranspiration, deep percolation, surface runoff, and capillary rise in the aerobic rice field on a daily basis. The model parameters are validated with the observed experimental field data from the Huibei Irrigation Experiment Station, Kaifeng, China. The validated model is used to analyze irrigation application soil water tension trigger under wet, dry and average climate conditions using daily time steps. The scenario analysis show that to conserve scarce water resources during the average climate years the irrigation scheduling criteria can be set as −30 kPa average root zone soil water tension; whereas it can be set at −70 kPa during the dry years, however, the associated yields may reduce. Compared with the flooded lowland rice and other upland crops, with these two alternatives irrigation event triggers, aerobic rice cultivation can lead to significant water savings.  相似文献   

17.
水稻是耗水第一大作物。发展节水栽培对稻田水分高效利用和缓解我国水资源短缺具有重要意义。水稻根系是吸收水分和养分的重要器官,也是多种激素、氨基酸和有机酸合成的重要部位。水分管理措施的改变会直接或间接引起根系生长发育发生改变,从而影响水稻地上部生长发育和产量形成。本文综述了干湿交替灌溉、控制灌溉和覆盖旱种对水稻根系形态和生理特性的影响,提出了今后节水灌溉下水稻根系的研究重点,以期为改善水稻根系形态生理和高产节水栽培提供理论依据。  相似文献   

18.
Rice cultivation has long been considered to have originated from seeding of annual types of wild rice somewhere in subtropics, tropics or in the Yangtze River basin. That idea, however, contains a fatally weak point, when we consider the tremendous difficulty for primitive human to seed any cereal crop in the warm and humid climate, where weed thrives all year round. Instead of the accepted theory, we have to see a reality that vegetative propagation of edible plants is a dominant form of agriculture in such regions. The possibility is discussed that Job's tears and rice, two cereal crops unique to the region, might have been developed via vegetative propagation to obtain materials for medicine or herb tea in backyard gardens prior to cereal production. This idea is supported by the fact that rice in temperate regions is still perennial in its growth habit and that such backyard gardens with transplanted taro can still be seen from Yunnan Province of China to Laos. Thanks to detailed survey of wild rice throughout China for 1970-1980, it is now confirmed that a set of clones of wild rice exist in shallow swamps in Jiangxi Province, an area with severe winter cold. In early summer ancient farmers may have divided the sprouting buds and spread them by transplanting into flooded shallow marsh. Such way of propagation might have faster improved less productive rice through a better genetic potential for response to human interference than quick fixation in seed propagation, because vegetative parts are heterogeneous. Obviously, such a primitive manner of rice cultivation did include the essential parts of rice farming, i.e., nursery bed, transplanting in flooded field of shallow marsh like. Transfer from the primitive nursery to true nursery by seed may have later allowed rice cultivation to be extended to northern regions. In thus devised flooded cultivation there were a series of unique advantages, i.e.; continuous cropping of rice in a same plot, no soil erosion, slow decline of soil fertility, availability of minerals, and resulting in high yield per unit area, which have collectively attained the highly productive cereal cultivation in the warm and humid region. Rice cultivation in marsh is also favorable to raise fish culture, both of which constituted a nutritionally balanced base. Development of irrigation technology to construct flooded farms gave strong bases for stable rice-cultivating society, which in the end formulated the rise of ancient kingdoms of Yue and Wu in China in BC 6 th -5th centuries. They were direct descendents of those people who had developed the unique rice cultivation from the era of Hemudu culture, which is dated back to 5 000 BC. Their movement to the south is considered to have established rice-cultivating communities in South China and Southeast Asia, while to the north it transferred the rice-based technology to ancient Korea and Japan and had established there a base for a civilized society.  相似文献   

19.
主要节水灌溉方式对水稻根系形态生理的影响   总被引:2,自引:0,他引:2  
水稻是耗水第一大作物。发展节水栽培对稻田水分高效利用和缓解我国水资源短缺具有重要意义。水稻根系是吸收水分和养分的重要器官,也是多种激素、氨基酸和有机酸合成的重要部位。水分管理措施的改变会直接或间接引起根系生长发育发生改变,从而影响水稻地上部生长发育和产量形成。本文综述了干湿交替灌溉、控制灌溉和覆盖旱种对水稻根系形态和生理特性的影响,提出了今后节水灌溉下水稻根系的研究重点,以期为改善水稻根系形态生理和高产节水栽培提供理论依据。  相似文献   

20.
The Unsteady Irrigation Water Distribution and Consumption (UIWDC) model is applied to analyze causes of uneven water distribution between the upstream and downstream beneficial areas of the Mae Lao Irrigation Scheme (MLIS). The uneven water distribution may be caused by inadequate water distribution facilities or improper operation rule; therefore, its causes are examined systematically and quantitatively from the aspects of “water allocation” and “operation rule”. The water allocation is considered focusing on the dry season irrigation, where equity and efficiency should be especially balanced because of the scare water resources. The “EQTY index” (the equity index) is defined to widen the range of consideration between the equity and the efficiency, instead of alternative judgment of which has a priority. The operation rule for facilities in the MLIS is assumed considering their capacities, and two coordinate values of “ineffective spillage” and “water deficit” in the scheduled areas are incorporated into operation rule to quantitatively diagnose the system performance. As a result, the original causes of uneven water distribution will presumably be identified. The informative and quantitative results are utilized to set a new benchmark performance of the MLIS for the water distribution. It can be described by the “Expected Ratio of Irrigable Area” (ERIA) and “Present Ratio of Irrigable Area” (PRIA). Based on this standard, the general recommendations can be more concretely proposed to raise the water distribution performance of the MLIS such as by improving distribution facilities and/or by installing vertical pumps.  相似文献   

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