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1.
冬季灌溉与桂味荔枝成花率的关系初探 总被引：1，自引：0，他引：1
2009年底至2010年初和2010年底至2011年初的连续2个冬季（每年12月至翌年的2月），通过提前搭建通风透光的遮雨棚，防止雨水淋到处理树上，模仿常年冬季自然的土壤干旱，再在干旱的遮雨棚内和露天果园里分别进行了1～4次、1～6次的不同灌溉处理，研究了桂味荔枝果园不同时段的地表水分变化与成花率的关系。结果表明：灌溉（含自然雨水灌溉）时间越早，灌溉次数越多，成花率就越高。2010年1月中旬以后的灌溉促花处理，成花很少；2011年2月中旬以后灌溉的处理，成花也很少。文章对“冬季干旱有利于荔枝成花”的传统观念进行了讨论, 提出“冬季适时、适度湿润，有利于桂味荔枝成花”的观点。 相似文献
2.
Models can play an important role in agricultural planning and management. Thermal time accumulation is a common way of describing phenological development in crop models, but the sensitivity of this concept to water stress is rarely quantified. The effect of pre-anthesis droughts on the timing of anthesis and physiological maturity was assessed for quinoa (Chenopodium quinoa Willd.) var. ‘Santa Maria’, with the help of two field experiments (2005–2006 and 2006–2007) in the central Bolivian Altiplano. Various treatments with different sowing dates and irrigation applications were considered. To evaluate the effect of drought stress on crop development, drought stress during the first 60 days after sowing was assessed with three different stress indicators: the number of days that the soil water content of the root zone was above a threshold, the average relative transpiration, and the sum of daily actual transpiration, standardized for reference evapotranspiration (∑(Ta/ET0)). The best indicator to quantify the effect of pre-anthesis drought stress on phenological development was ∑(Ta/ET0) cumulated until 60 days after sowing. This indicator showed a significant logarithmic relation with the time to anthesis and time to physiological maturity. Correlations of the drought stress indicator with thermal time accumulation were better than with calendar time accumulation. Due to an effect of post-anthesis droughts, the correlations of the drought stress indicator with the time to anthesis were stronger than with the time to physiological maturity. It was also demonstrated that deficit irrigation can contribute to a better agricultural planning due to a better control of the phenological development of quinoa. The proposed relations can be used for modeling phenological development of quinoa in drought prone regions and for efficient deficit irrigation planning. 相似文献
3.
In Northeast Thailand, which overlaps with an erosional plain that is not suitable for irrigation because of poor water resources and terrains that prevent efficient water distribution, farmers have long supplied water to surrounding paddy fields by blocking rivers completely with earthen bunds. Although such a traditional irrigation system fits well with the characteristics of Northeast Thailand, those who are concerned with modern irrigation development projects in Northeast Thailand seem to have been paying little attention to it. The present study was performed to facilitate development of more appropriate irrigation systems in Northeast Thailand by providing information regarding traditional irrigation methods. We investigated the traditional irrigation methods with earthen bunds at three study sites, and our results indicated that styles of irrigation vary with riverbed slope. The traditional irrigation system that is used in most of Northeast Thailand is different from ordinal weir irrigation, in that paddy fields are not irrigated by gravity flow but by backwater of earthen bunds. Our results suggest that the development of more successful irrigation systems would be possible through improvement of the design ideas of traditional irrigation methods.
相似文献
| Keisuke HoshikawaEmail: |
4.
干湿交替灌溉对抗旱性不同水稻品种产量的影响及其生理原因分析 总被引：8，自引：2，他引：6
【目的】旨在阐明全生育期干湿交替灌溉对抗旱性不同水稻品种产量的影响。【方法】以抗旱性差异显著的4个水稻品种(籼稻扬稻6号和两优培九,粳稻旱优8号和镇稻88)为材料,以常规水层灌溉(CI)为对照,在盆栽条件下研究了轻干湿交替灌溉(WMD)和重干湿交替灌溉(WSD)对水稻产量、根系、叶片及籽粒部分生理特性的影响。【结果】与CI相比,WMD处理下抗旱性较强品种扬稻6号和旱优8号产量分别提高6.90%和7.45%,抗旱性较弱品种两优培九和镇稻88产量分别降低7.28%和8.10%。WSD处理下,4个水稻品种的产量均显著下降,抗旱性较弱的品种产量降幅远高于抗旱性较强的水稻品种。WMD处理下,扬稻6号和旱优8号复水后根系氧化力、根系与叶片细胞分裂素(玉米素+玉米素核苷)含量、叶片光合速率和籽粒中蔗糖-淀粉代谢途径关键酶的活性均较CI有不同程度提高,而两优培九和镇稻88上述指标则与CI持平或有不同程度降低。WSD处理下,4个品种上述指标均较CI不同程度降低。【结论】轻干湿交替灌溉条件下,根系活性强、叶片细胞分裂素含量和光合速率高、籽粒中蔗糖-淀粉代谢途径关键酶活性强是抗旱性较强水稻品种的基本生理特征。 相似文献
5.
Decision support system for reservoir operation considering rotational supply over irrigation blocks
This study aims not only to evaluate agricultural drought in paddy using the storage ratio of the corresponding reservoir, but also to develop a rotational irrigation scheduling system (RISS) for supporting both water supply scheduling and on–off control works for automated irrigation. From the present storage ratio of reservoir and an operation rule curve (ORC) as a guideline for releasing irrigation water, reservoir operators could determine the appropriate time to restrict the irrigation water supply, and calculate the deficient amount of irrigation water. The RISS based on the ORC and weekly rainfall forecasting information has been developed for decision support to minimize drought damage in irrigation districts during the irrigation period. The system was also applied to a test irrigation district with the Yedang irrigation reservoir, which is located in the mid-west of Korea. The RISS could be utilized as a water management program for irrigation reservoirs by interfacing with telemetering and telecontrol (TM/TC) technology. 相似文献
6.
Tatsuki Ueda Shigeo Ogawa Katsuro Shioda Pongsak Arulvijitskul Phonchai Klinkhachorn 《Paddy and Water Environment》2005,3(1):63-71
This study aims to investigate recent practices on water allocation and cultivation in the Upper East Bank of the Chao Phraya Delta in Thailand, by using data collected by RID local offices, questionnaires, and analyses of satellite images. As a result, we have identified the advantage that upstream areas of irrigation canals have enjoyed, namely the preferential water allocation over the downstream areas. This advantage was strongly associated with the intensive cropping patterns of rice: the upstream areas were estimated to conduct almost continuous rice cultivation throughout a year. In addition, the intensive rice cultivation would partly be supported by water from private shallow wells, which were mostly concentrated in the upstream areas of main canals. Those shallow wells would be used at the beginning of the dry season and in drought years, when farmers could not expect water supply from irrigation canals. The result indicated that the conjunctive use of surface and ground water would be practiced in this region. 相似文献
7.
Brown rot can lead to considerable fruit losses in peach orchards and cultural practices likely to contend this major disease have to be promoted. In order to limit peach brown rot incidence in a three-year-old mid-season maturing peach orchard of the cultivar ’Ruby Bright’, four combinations of irrigation and soil management treatments were assessed: conventional (Conv) irrigation (I) and soil management (S) (ConvI+ConvS); modified (Mod) irrigation and soil management (ModI+ConvS); conventional irrigation and modified soil management (ConvI+ModS); and modified irrigation and soil management (ModI+ModS). Conventional irrigation and soil management in the tree row consisted of irrigation scheduling using tensiometer readings and herbicide use, respectively. Modified irrigation and soil management in the tree row consisted of water deprivation during stage III of fruit development and ground cover with white clover, respectively. For four consecutive years (2010–2013), in the conditions of the Middle Rhone Valley in France, the lowest and highest brown rot incidence were detected under (ModI+ModS) and (ConvI+ConvS), respectively, whereas brown rot incidence under (ModI+ConvS) and (ConvI+ModS) was intermediate. This lower brown rot incidence under the modified treatments occurred from one to two weeks before fruit maturity and was still observed for several days in post-harvest storage. Ground cover with white clover was shown to limit water availability in the soil after heavy rainfall compared to bare soil, probably limiting peach growth variations, well-known as a possible source of detrimental microcracks at the fruit surface. This suggests that under our conditions appropriate cultural practices, water deprivation and a clover crop cover in the tree row possibly decrease peach disease sensitivity, which might lead to the reduced use of pesticide sprays to control brown rot in the orchard. 相似文献
8.
《Plant Production Science》2013,16(1):1-14
AbstractDrought is the major constraint to rice production in rainfed areas across Asia and sub-Saharan Africa. In the context of current and predicted water scarcity, increasing irrigation is generally not a viable option for alleviating drought problems in rainfed rice-growing systems. It is therefore critical that genetic management strategies for drought focus on maximum extraction of available soil moisture and its efficient use in crop establishment and growth to maximize biomass and yield. Extensive genetic variation for drought resistance exists in rice germplasm. However, the current challenge is to decipher the complexities of drought resistance in rice and exploit all available genetic resources to produce rice varieties combining drought adaptation with high yield potential, quality, and resistance to biotic stresses. The strategy described here aims at developing a pipeline for elite breeding lines and hybrids that can be integrated with efficient management practices and delivered to rice farmers. This involves the development of high-throughput, high-precision phenotyping systems to allow genes for yield components under stress to be efficiently mapped and their effects assessed on a range of drought-related traits, and then moving the most promising genes into widely grown rice mega-varieties, while scaling up gene detection and delivery for use in marker-aided breeding. 相似文献
9.
陕西省不同年代旱地冬小麦光合与产量特征变化及其相互关系研究 总被引：2，自引：0，他引：2
为明确陕西省不同年代旱地冬小麦品种光合特征变化规律及其对产量的影响,选择曾在该省推广种植的20世纪40年代至21世纪初8个不同年代旱地冬小麦品种(蚂蚱麦,1940s;碧蚂1号,1950s;丰产3号,1960s;泰山1号,1970s;小偃6号,1980s;陕229,1990s;长武134,2000s;长旱58,2010s)为材料,设置正常供水和干旱胁迫两个水分处理,进行盆栽种植试验,对小麦不同生育期光合特征进行测定,并在收获期考种测产。结果表明,无论是干旱胁迫还是正常供水处理下,现代小麦品种(长武134和长旱158)花前旗叶净光合速率和单株叶面积都表现出显著优势,并与千粒重和产量呈显著正相关;但品种间花后光合特征差异减小,这对于现代小麦产量的提升可能产生了一定的限制作用;不同生育时期和不同水分处理下,旗叶蒸腾速率与种植年代之间相关性并不一致;干旱胁迫条件下,孕穗期和花后3d的旗叶水分利用效率都随品种更替呈明显上升的趋势;现代小麦品种在干旱处理下旗叶净光合速率等光合特征、千粒重等产量因素的优势受到影响,最终导致其产量增幅下降。未来应进一步提升现代小麦的光合优势,尤其是花前叶片净光合速率及叶面积的优势,并进一步提高千粒重,这将会是陕西省小麦节水高产和抗旱稳产的重要手段。 相似文献
10.
11.
季节性干旱是限制菠萝增产提质增效的重要原因,发展“以水促肥,以肥促产,水肥高效耦合”的现代灌溉施肥技术,是应对季节性干旱,促进菠萝增产提质增效的重要途径。本文从华南地区季节性干旱时空分布特征、干旱胁迫对菠萝生长发育的影响、我国菠萝水肥管理现状、灌溉施肥技术对菠萝生长发育的影响等4个方面简要阐述了我国菠萝灌溉施肥技术发展的必要性,重点从现代灌溉施肥方式、耗水规律和养分吸收规律等3方面总结了菠萝灌溉施肥技术研究进展,并结合研究进展提出我国菠萝灌溉施肥技术目前存在的问题,探讨未来可能的研究重点和发展方向,为菠萝灌溉施肥技术的研究与应用提供参考。 相似文献
12.
探讨分根区灌溉和氮肥对盆栽星油藤幼苗生长的影响。试验设置3个因素，灌水量、灌溉方式和氮肥，共7个处理，测量了幼苗生长、光合和水分利用效率等指标。结果表明：与充分灌溉相比，分根区灌溉的处理，生物量降低5％，节水75％，水分利用率高出60％，表现出极大的节水效益。重度干旱条件下，施氮肥的处理，根冠比增加达30％，但分根区灌溉处理叶面积指数下降38％，光合速率下降9％，生物量下降18％，分根区灌溉在严重干旱条件不适宜施氮肥。总之，在适度干旱条件下，分根区灌溉降低蒸腾，提高水分利用率，是一种有效的节水灌溉技术。 相似文献
13.
Farmers in some parts of the Indochina Peninsula have been using earthen weirs to supply water to their rice fields, and the
use of such weirs is especially prevalent in Northeast Thailand. Although now a typical rain-fed rice cultivation area, a
significant percentage of rice fields in Northeast Thailand used earthen weirs before the extensive expansion of rain-fed
rice fields that occurred in the early 20th century. In this study, we clarified some of the historical changes associated
with the construction and use of earthen weirs and their effects on rice production. In particular, we investigated some of
the topographic effects, such as terrain, catchment size, and slope grade, on water delivery. In addition, water delivery
methods, construction periods, and the discontinued use of earthen weirs were examined with respect to regional influences
and topography. Earthen weirs were found to be most suitable in areas that exhibited complementarity between the riverbed
slope and the water catchment. The type of earthen weir was dependent on the magnitude of the riverbed slope. Earthen weirs
have been constructed continuously on steeper upstream slopes of rivers for more than a century, while weir construction on
lower riverbeds with larger catchments appears to be more recent.
相似文献
| Keisuke HoshikawaEmail: |
14.
Current modernization of an irrigation system degrades fish habitats in quantity and quality and is a significant concern for biodiversity conservation and management of ecosystem services in rice farming landscapes. Irrigation systems consist of various types of channels, whose hydrological and hydraulic heterogeneities can contribute to the coexistence of diverse fish species in this flooded habitat. We compared seasonal patterns of fish species richness and abundance between main and branch channels which have different functions in an irrigation system with different flow temporality and magnitude: the main channels (mean width 425 cm and mean discharge 0.467 m3/s in irrigation period) and the branch channels (176 cm and 0.115 m3/s, respectively). The branch channels are small and temporary, but densities of fish species richness and abundance were not smaller than the main channels during the irrigation period. Further, clear positive hysteretic loops in species richness and abundance with discharge were found in the branch channels, which indicates that fish species richness and abundance gradually increased with discharge during this hydroperiod. Water velocity strongly constrained species richness and abundance in the main channels but not in the branch channels partially because of slow-flow patches at microhabitat scale with a larger vegetation coverage. We also found that the main channels provided deeper habitats in the non-irrigation period and contributed to maintain fish species richness and abundance. Therefore, managing both the main and branch channels as an indispensable, interconnected channel network can be a key for fish habitat conservation in an irrigation system. 相似文献
15.
Summary A major objective of plant breeding programmes in semi-arid conditions is the selection of more drought-tolerant plant material.
An irrigation system has been developed to assist in water use and drought tolerance screening studies of potato genotypes
in the confined space of a rain shelter. The line-source principle was used as a departure point for the design of an irrigation
boom, attached to the roof structure of a rain shelter. Five water regimes were achieved by using nozzles that differed in
discharge rate and three genotypes per rain shelter were evaluated simultaneously.
Crop production functions could be established for the different genotypes. The system shares some disadvantages of the typical
line-source, such as the simultaneous irrigation of all plots and water treatments are not randomised. The main advantage
above traditional plot systems, which would use drip or micro irrigation under rain shelters, is the ease of management. 相似文献
16.
Delivery management water requirement (DMWR) is the use of bypass water in paddy field irrigation to help maintain desired water levels in irrigation canals and to distribute water to paddy plots in a uniform manner. Diverted irrigation water (DIW), DMWR, and the DMWR/DIW ratio were investigated for concrete lined irrigation ditches with large-sized paddy plots (100 m×100 m) during irrigation periods (May to mid-September). DIW and DMWR were measured at 5- to 10-day intervals at the inlets and outlets of irrigation ditches on stable water supply days. The mean DMWR/DIW ratios in irrigation ditches L1 and L2 over 3 years were 36 and 34%, respectively. The mean DMWR/DIW ratios displayed month-to-month and year-to-year variation. The monthly mean DMWR/DIW ratios were highest (55 and 71%) in June and lowest (<20%) in August and September. The annual mean DMWR/DIW ratios during a dry year markedly decreased to 11%, compared with 42% in other years. The decrease was due to the small DIW and farmers water management to maximize capture of limited irrigation water during the drought. The DMWRs in May and June were significantly (p<0.01) correlated with the DIWs, indicating that high DMWR in May and June are attributed to excessive DIW. 相似文献
17.
J. C. Stark S. L. Love B. A. King J. M. Marshall W. H. Bohl T. Salaiz 《American Journal of Potato Research》2013,90(3):207-216
The ability to minimize potato yield and quality losses due to drought can be greatly improved by understanding the relative responses of different cultivars to seasonal variations in water supply. To address this need, we initiated a 2 year field experiment to determine the responses of the six potato cultivars to different seasonal drought patterns, including 1) full season irrigation at 100 % ET, 2) irrigation at 100 % ET terminated during late bulking , 3) full season irrigation at 70 % ET , 4) irrigation at 70 % ET terminated during late bulking , and 5) a gradual reduction in irrigation from 100 % ET during tuber initiation through early bulking, to 70 % ET during mid-bulking, and 50 % ET through late bulking. GemStar Russet and Ranger Russet, two medium-late maturing cultivars, generally produced the highest yields across the range of drought treatments, but both were fairly sensitive to changes in drought severity. Alturas, a late maturing cultivar, produced relatively high yields with full irrigation, but exhibited the greatest sensitivity to increasing drought severity, particularly when severe late-season water deficits were imposed. Yields for the early maturing cultivar Russet Norkotah were relatively low overall, but it was the least sensitive to changes in drought severity, particularly when late season drought was imposed. Russet Burbank produced comparatively high total yields across the range of drought treatments, but U.S. No. 1 yields were substantially reduced by each seasonal drought pattern. However, it was less sensitive to changes in drought severity than GemStar Russet, Ranger Russet and Alturas. Total and U.S. No. 1 yields for Summit Russet were low for each drought treatment and it exhibited intermediate sensitivity to changes in drought severity. GemStar Russet had the highest water use efficiency based on U.S. No. 1 yield. 相似文献
18.
Won-Ho Nam Jin-Yong Choi Seung-Hwan Yoo Min-Won Jang 《Paddy and Water Environment》2012,10(3):197-207
Since predicted changes in climate will modify temperature and rainfall patterns, there are concerns about the potential impacts of these changes on agricultural drought and agricultural water resources management. An agricultural drought is influenced by several factors such as rainfall, soil characteristics, crops, and reservoir water supply and may be defined as the imbalance of water circulation in paddy and water environments. In particular, soil moisture and water supply for reservoir demand are the most direct and important indicators of agricultural drought events. In the past, conventional drought management approaches based on climatic and meteorological observations have been the primary tools used for measuring drought severity. Because of the spatial and temporal variability and multiple impacts of drought, it is necessary to improve tools to determine the onset, severity, spatial extent, and end of the drought conditions. Improved and available data for mapping and monitoring of this phenomenon are also needed. Effective and efficient drought management can be achieved through drought monitoring based on the ability to assess current conditions and provide improved tools to adapt and mitigate the impacts of future changes. In this article, a methodology is developed to support the risk-based decision-making process involved in agricultural drought management using the following four strategies: drought assessment and monitoring, drought forecast and outlook, drought countermeasures, and drought records management. 相似文献
19.
20.
《Plant Production Science》2013,16(2):182-188
AbstractNo-tillage often affects crop root development due to the higher mechanical impedance to root elongation, resulting in yield reduction under an unfavorable rainfall pattern, such as drought. In this study, we analyzed the changes in water source of wheat and soybean under drought stress in a continuous no-tillage field. Deuterium-labeled irrigation water was applied at different growth stages of crops to analyze their water uptake pattern. Mechanical impedance of the surface soil was 3.5 and 4.4 times higher in the no-tillage than in the conventional tillage under wet and drought conditions, respectively. Root length density and root branching index (the length of lateral roots per unit axile root length) of soybean in the surface soil layer were higher in the no-tillage field. This indicates that the increased branching by the higher mechanical impedance of undisturbed surface soil causes roots to accumulate in the surface soil layer. The deuterium concentration in the xylem sap of both crops was significantly higher in the no-tillage than in the tillage under a drought condition. This indicates that the crops in the no-tillage field depend highly on the newly supplied easily accessible water (irrigation water and/or rainfall) as compared with those in the conventional tillage field under a limited water supply. In conclusion, enhanced surface root growth in the no-tillage condition would result in higher dependence on surface supplied irrigation water than in the conventional tillage under drought. 相似文献