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1.
本文研究了水分胁迫对红麻生长发育的影响及湘南红壤旱地红麻水、肥的调控效应。结果表明 :水分胁迫降低了生长速度 ,减少了植株叶面积 ,抑制干物质积累 ,促进了根/冠比。旺长后期对水分胁迫的反应较旺长前期敏感。旱地红麻生育期短 ,生殖生长较强 ,生麻产量较低 ,种子产量较高。增施肥料结合覆盖或旺长后期 (旱期 )透灌一次 ,是红壤旱地红麻纤维、种子兼收高产高效的有效措施。 相似文献
2.
红麻水分胁迫及水,肥效应研究 总被引：2，自引：0，他引：2
本文研究了水分胁迫对红麻生长发育的影响及湘南红壤旱地红麻水、肥的调控效应。结果表明：水分胁迫降低了生长速度,减少了植株叶面积,抑制干物质积累,促进了根／冠比,旺长后期对水分胁迫的反应较旺长前期敏感,旱地红麻生育期短,生殖生长较强,生麻产量较低,种子产量较高,增施肥料结合覆盖或旺长后期（旱期）透灌一次,是红壤旱地红麻纤维、种子兼收高产高效的有效措施。 相似文献
3.
观察红壤旱地上红麻的生长特性,发现红麻生长动态具有两个明显的旺长阶段,分别在6月上旬至7月上旬和8月上中旬至9月上旬,且前者旺长高峰高于后者,两个旺长阶段与气温有相关性,与降雨量关系甚密。文中并就红壤红麻旺长特性的播种期、施肥数量与配方和密度等栽培技术,进行了分析。 相似文献
4.
红麻旺长期的冠层光能利用率以叶面积系数3.5最高,超过4则形成大量消费叶。小于2则冠层透光率过大,光能利用不足。旺长期后,由于红麻植株冠层顶部变尖,株型向有利于吸收更多光能的方向改变,叶面积系数在5以上能获得更大的光合产量。红麻的生长速率在旺长初至旺长中期上升最快,旺长中期与开花前都维持较高水平,但旺长后期(7/下—8/上),叶面积系数达最高4左右,个体与群体生长明显不协调,这以后中下部大量叶片转化为消费叶,从而导致8月下旬出现生长速率低谷。净同化率则在苗期、旺长中期及纤维积累盛期均较大,而旺长中期之前,由于新叶发生速度快,叶面积系数迅速上升及旺长后期叶片衰老,叶面积比下降幅度大,相对生长速率降低,这两个时期的净同化率相对较低。 相似文献
5.
红麻旺长期的冠层光能利用率以叶面积系数３．５最高，超过４则形成大量消费叶，小于２则冠层透光率过大，光能利用不足，旺长期后，由于红麻植株冠层顶部变尖，株型向有利于吸收更多光能的方向改变，叶面积系数在５以上能获得更大的光合产量。红麻的生长率在旺长初至旺长中期上升最快，旺长中期与开花前都纤维较高水平，但旺长后期（７／下－８／上），叶面积系数还最高４左右，个体与群体生长明显不协调，这以后中下部大量叶片转化 相似文献
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采用５因素二次正交旋转组合设计的方法，研究了播种期、定苗密度、氮、磷、钾施用量等５项农艺措施对红壤旱地红麻纤维、种子产量和产值的影响以及各措施之间的关系，获得了红壤旱地红麻纤维和种子兼收、高产高效的综合农艺措施组合方案，并对试验因子的主效应及工作效应进行了剖析。 相似文献
9.
采用５因素二次正交旋转组合设计的方法，研究了播种期，定苗密度，氮，磷，钾施用量等５项农艺措施对红壤旱地红麻纤维，种子产量和产值的影响以及各措施之间的关系，获得了红壤旱地红麻纤维和种子兼收，高产高效的综合农艺措施组合方案，并对试验因子的主效应及工作效应进行了剖析。 相似文献
10.
花后水分亏缺对冬小麦光合特性及产量的影响 总被引：4，自引：1，他引：3
为给小麦高产和生育后期抗旱栽培提供理论依据,盆栽试验条件下,选用旱地小麦品种长武134、长旱58和水地小麦品种西农9871作为试验材料,研究了花后水分亏缺对不同生态型小麦光合特性及产量的影响.结果表明,花后水分亏缺对小麦灌浆期旗叶光合速率(Pn)和荧光参数(Fv/Fo和Fv/Fm)、籽粒产量、收获指数及水分利用效率均有明显影响.与对照相比,中度水分亏缺下两个旱地小麦品种Pn除花后24 d外变化均不明显,Fv/Fo和Fv/Fm有升高趋势,产量和收获指数变化也不显著,水分利用效率明显提高;在重度水分亏缺下,Pn、Fv/Fo、Fv/Fm、产量和收获指数均降低,水分利用效率长武134依然高于对照,而长旱58明显降低.水地小麦西农9871的Pn、Fv/Fo、Fv/Fm随水分亏缺程度的加重呈下降趋势,产量和收获指数与旱地小麦变化相似,水分利用效率处理间差异较小.说明旱地小麦受花后水分亏缺的不利影响小于水地小麦,表现出较高的水分利用能力. 相似文献
11.
Yasushi Ishigooka Tsuneo Kuwagata Shinkichi Goto Hitoshi Toritani Hiroyuki Ohno Shin-ichi Urano 《Paddy and Water Environment》2008,6(1):55-71
The relationship between agricultural water demand and supply has been of interest to government decision makers and scientists
because of its importance in water resources management. We developed a water cycle model for eastern Eurasia that can estimate
water requirements for crop growth and evaluate the demand–supply relationships of agricultural water use on a continental
scale. To produce an appropriate water cycle, the model was constructed based on small drainage basins. To validate the model
performance with respect to simulated runoff, which is here considered as the available water resource, we compared our outputs
with those of other models and with observed river discharges. The results show that this model is comparable to other models
and that it is applicable for the evaluation of water cycles at continental scale. We defined two types of crop water deficits
(CWDs) as indicators of agricultural water demand. These were formulated by considering the physical processes of crop water
use; we did not include water consumption that is dependent on cultivation management practices, such as water losses in irrigation
systems. We assessed the reliability of our indicators by comparison with indicators from other studies and with published
statistics related to agricultural water use. These comparisons suggest that our indicators are consistent with independent
data and can provide a reasonable representation of water requirements for crop growth. 相似文献
12.
V. Phogat A. K. Yadav R. S. Malik Sanjay Kumar Jim Cox 《Paddy and Water Environment》2010,8(4):333-346
The HYDRUS-ID model was experimentally tested for water balance and salt build up in soil under rice crop irrigated with different
salinity water (ECiw) of 0.4, 2, 4, 6, 8 and 10 dS m−1 in micro-lysimeters filled with sandy loam soil. Differences of means between measured (M) and HYDRUS-1D predicted (P) values of bottom flux (Q
o) and leachate EC as tested by paired t test were not found significant at P = 0.05 and a close agreement between RMSE values showed the applicability of the HYDRUS-1D to simulate percolation and salt
concentration in the micro-lysimeters under rice crop. Potential ET values of rice as obtained from CROPWAT matched well with
model predicted and measured one at all ECiw treatments. The model predicted root water uptake varied from 66.1 to 652.7 mm
and the maximum daily salt concentration in the root zone was 0.46, 2.3, 4.5, 6.7, 8.4 and 10.2 me cm−3 in 0.4, 2, 4, 6, 8 and 10 dS m−1 ECiw treatments, respectively. The grain production per unit evapotranspiration (
\textWP\textET\texta {\text{WP}}_{{{\text{ET}}_{\text{a}} }} ) value of 2.56 in ECiw of 0.4 dS m−1 treatment declined to 1.31 with ECiw of 2 dS m−1. The
\textWP\textET\texta {\text{WP}}_{{{\text{ET}}_{\text{a}} }} reduced to one-fifth when percolation was included in the productivity determination. Similarly, the water productivity in
respect of total dry matter production (TDM) was also reduced in different treatments. Therefore, the model predicted values
of water balance can be effectively utilized to calculate the water productivity of rice crop. 相似文献
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14.
Geneille E. Greaves 《Plant Production Science》2017,20(4):353-365
As the challenges toward increasing water for irrigation become more prevalent, knowledge of crop yield response to water can facilitate the development of irrigation strategies for improving agricultural productivity. Experiments were conducted to quantify maize yield response to soil moisture deficits, and assess the effects of deficit irrigation (DI) on water productivity (water and irrigation water use efficiency, WUE and IWUE). Five irrigation treatments were investigated: a full irrigation (I1) with a water application of 60 mm and four deficit treatments with application depths of 50 (I2), 40 (I3), 30 (I4), and 20 mm (I5). On average, the highest grain yield observed was 1008.41 g m?2 in I1, and water deficits resulted in significant (p < .05) reduction within range of 6 and 33%. This reduction was significantly correlated with a decline in grain number per ear, 1000-grain weight, ear number per plant, and number of grain per row. The highest correlation was found between grain yield and grain number per ear. The WUE and IWUE were within range of 1.52–2.25 kg m?3 and 1.64–4.53 kg m?3, respectively. High water productivity without significant reduction in yield (<13%) for I2 and I3 compared to the yield in I1 indicates that these water depths are viable practices to promote sustainable water development. Also, for assessing the benefits of irrigation practices in the region crop water production functions were established. Maize yield response to water stress was estimated as .92, suggesting the environmental conditions are conducive for implementing DI strategies. 相似文献
15.
Vassilis Z. Antonopoulos 《Paddy and Water Environment》2008,6(4):387-395
A water and nitrogen balance model for the surface ponded water compartment of rice fields was developed. The model estimates
the daily ponded water depth and the daily losses and the uses of NH4–N and NO3–N in their transformation processes. The model was applied with data obtained from two rice fields during 2005 at Thessaloniki
plain in northern Greece. Significant amounts of applied irrigation water were lost with the surface runoff and deep percolation
to groundwater. The gaseous losses of nitrogen (volatilization and denitrification) and nitrogen uptake by algae were the
main processes of nitrogen reduction in the ponded water of rice fields. The study showed that the system of a rice field
is a natural system where an important amount of influent nitrogen applied by irrigation water can be reduced. These processes
decrease the possibilities of water resources contamination. 相似文献
16.
Paddy and Water Environment - Rice production is one of the largest consumer of water in agriculture. In general, the irrigation water productivity (WPI) is low in paddy fields. In order to improve... 相似文献
17.
Rahman Mohammed M. Hasan Shafee Ahmed Md. Razu Adham A. K. M. 《Paddy and Water Environment》2022,20(4):449-466
Paddy and Water Environment - Rice is critical to maintaining nutritional demand and food security of many Asian and African nations. The high water demanding rice is traditionally cultivated with... 相似文献
18.
In closed water bodies, such as reservoirs and lakes, where the exchange with external waters is usually small, the wind-induced
flow significantly affects their water quality by mixing the surface waters and transfering heat down through the water column.
However, the circulation caused by wind acting on the water surface can be influenced by the excessive growth of aquatic plants
in summer, which may make their water quality to become worse. Therefore, understanding the response of the closed water bodies
to winds acting on the water surface is of great significance in examining and maintaining their water quality in good condition.
With that significance, this research has been done to build a two-dimensional, unsteady, laterally averaged model for simulating
the circulation and water quality in closed water bodies. To verify the model, the Tabiishidani reservoir located in Sasaguri
town, Fukuoka prefecture, Japan, was chosen as a case study. To illustrate the methodology of the research, water temperature
of the reservoir was chosen to calibrate the model. After calibration, the model was applied to simulate water temperature
in the Tabiishidani reservoir under different patterns of meteorology. The results of simulation clarified the change in water
temperature distribution along the depth of the reservoir under the different patterns of meteorology. This research shows
that the model can be a suitable tool for simulating the circulation and water temperature in closed water bodies. Moreover,
the model can be extended to simulate the circulation and any variable of water quality in closed water bodies with the coverage
of aquatic plants on the water surface. 相似文献
19.
Water stress affects the rate of water uptake, biomass accumulation and structural growth of sugarcane differently and, consequently, alters the partitioning of assimilate to sucrose storage. The CANEGRO sugarcane model is unable to accurately simulate the subtle rate changes in the source and sink processes during the progression of water stress during dry spells, with subsequent poor prediction of sucrose yields. The aim of this study was to test eight different water balance models by comparing simulated and experimentally determined rates of water uptake (WU), carbon assimilation (CAR), plant extension (PER) and sucrose accumulation (SA). 相似文献
20.
Ya-Wen Chiueh 《Paddy and Water Environment》2012,10(1):41-47
In this study, the demand function for the transferring agricultural water to industrial water during non-drought period covering
from January 1998 to December 2008 in Taiwan was estimated, and the water usage statistics derived from the short-term water
charge agreements, regarding the charging of water management fees and water usage fees from the irrigation associations,
were applied to the estimation in the empirical model. The results of the research are presented as follows: (a) the demand
for transferring agricultural water into industrial water is non-elastic; the price elasticity is −0.368; (b) the transferred
water volume decreases when the water price rises; (c) the transferred water volume also decreases when the wholesale price
index of domestic products rises; (d) the buyer’s industry classification was the significant factor influencing the transfer
water demand; (e) the different title of transferred water including: “building utilization cost” or that in “costs for enhanced
irrigation management” was the significant factor influencing the transfer water demand; (f) type of repository of irrigation
association for transferred water was the significant factor influencing the transfer water demand; (g) whether irrigation
association enhances irrigation management was the significant factor influencing the transfer water demand; (h) the source
of transferred water was the significant factor influencing the transfer water demand; (i) the method for water transfer was
the significant factor influencing the transfer water demand; (j) more water transferred by the industry when the total population
of Taiwan increases; (k) the transferred water volume rises when the groundwater level of the water transferred area rises;
and (l) the areas for water transferred was the significant factor influencing the transfer water demand. 相似文献