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1.
我国主要水稻雄性不育系的光温特性研究 总被引：3，自引：1，他引：3
根据10个水稻雄性不育系的生育期及期间的温度和日长资料，研究了它们的光、温生态特性。用通径分析方法，分析了决定各不育系生育期变化的决策变量结果表明：晚籼及晚粳类型不育系的感光性强，中籼类型不育系的感光性弱到中等，早籼类型不育系的感光性一般都弱。10个雄性不育系中感温性弱的只占少数，感温性属弱到中强的品种占多数。除HS-3和SE21S的生育期决策变量为日长外，其他各不育系的决策变量均为温度。 相似文献
2.
水稻光合特性研究综述 总被引：3，自引：0，他引：3
光合作用是作物生长发育和产量形成的生理基础,也是作物生产力高低的决定性因素,国内外进行了大量研究。本文查阅相关资料从水稻的光合特性、光照、CO2浓度、温度、水分、栽培方式、土壤因素等环境因素对水稻光合作用的影响等方面进行综合分析,阐述水稻光合特性的研究进展。 相似文献
3.
本文应用灰色系统理论,分别建立了南宁市的秋季寒露风、冬季菠萝低温、春季烂秧天气结束期的时间序列的灰色动态(GM)长期预测模型,预测的效果较令人满意。其优点为:①可以减少时间序列的随机性;②可以提高预测精度。 相似文献
4.
Assessing the impacts of climate change on rice yields in the main rice areas of China 总被引：8，自引：1，他引：8
Fengmei Yao Yinglong Xu Erda Lin Masayuki Yokozawa Jiahua Zhang 《Climatic change》2007,80(3-4):395-409
This paper assesses the impact of climate change on irrigated rice yield using B2 climate change scenario from the Regional
Climate Model (RCM) and CERES-rice model during 2071--2090. Eight typical rice stations ranging in latitude, longitude, and
elevation that are located in the main rice ecological zones of China are selected for impact assessment. First, Crop Estimation
through Resource and Environment Synthesis (CERES)-rice model is validated using farm experiment data in selected stations.
The simulated results represent satisfactorily the trend of flowering duration and yields. The deviation of simulation within
± 10% of observed flowering duration and ± 15% of observed yield. Second, the errors of the outputs of RCM due to the difference
of topography between station point and grid point is corrected. The corrected output of the RCM used for simulating rice
flowering duration and yield is more reliable than the not corrected. Without CO2 direct effect on crop, the results from the assessment explore that B2 climate change scenario would have a negative impact
on rice yield at most rice stations and have little impacts at Fuzhou and Kunming. To find the change of inter-annual rice
yield, a preliminary assessment is made based on comparative cumulative probability at low and high yield and the coefficient
variable of yield between the B2 scenario and baseline. Without the CO2 direct effect on rice yield, the result indicates that frequency for low yield would increase and it reverses for high yield,
and the variance for rice yield would increase. It is concluded that high frequency at low yield and high variances of rice
yield could pose a threat to rice yield at most selected stations in the main rice areas of China. With the CO2 direct effect on rice yield, rice yield increase in all selected stations. 相似文献
5.
两系法杂交稻65396在我国一季稻区的制种播差期决策 总被引：1，自引：0，他引：1
以具有超高产水平的两系杂交稻 6 5 396 (培矮 6 4 s× E32 )为研究对象 ,在分析母本不育系培矮 6 4 s用作单季稻区域制种时的稳定不育期的季节和持续期的基础上 ,用生育期模型分析了培矮 6 4 s与 E32在南方一季稻区制种时的播差期及其变化规律。研究得到的两系法杂交稻制种技术的气象学方法可供其他熟制地区应用。 相似文献
6.
7.
滇中水稻冷害的强低温长期预报 总被引：1，自引：1，他引：1
本文分析了昆明(能代表滇中地区)3—8月月积温及8月平均气温对水稻产量的影响,提出了水稻冷害的低温指标。 本文得到:3—8月500毫巴西太平洋副高的强弱是影响昆明同期气温高低的重要因素,而该副高的强度有较好的持续性,故可据该副高1—2月的强度,预报滇中水稻冷害低温的有无。 另外得出:西太平洋副高春夏季的强度,在上年11月已有反映,故可更早作出有无水稻冷害低温的估计。 相似文献
8.
9.
成都平原稻田甲烷排放的实验研究 总被引：9，自引：0，他引：9
任丽新 王庚辰 张仁健 段长麟 M. A. K. Khalil M. J. Shearer R. A. Rasmussen R. W. Dalluge 《大气科学》2002,26(6):731-743
根据1996～1999年四个稻季的观测资料,分析了成都平原单季稻甲烷排放的季节变化和年际变化特征.结果表明:在水稻生长季节甲烷排放通量变化很大,在分蘖期和成熟期一般会出现峰值.年际间的通量变化也很大,其年均排放通量的变化范围在2.35～33.95mg m-2 h-1之间.4年的平均排放通量为12 mg m-2 h-1,与四川乐山的7年平均值30mg m-2 h-1相比,存在着明显的地区差异.同时分析讨论了温度、施肥、水稻品种、土壤氧化还原电位(Eh)以及稻田水位等诸多因素对稻田甲烷排放的影响.结果表明:在成都平原水稻生长季节的平均气温对CH4的平均排放通量影响不大;而气温对CH4排放的日变化有相对重要的影响,但气温对甲烷排放日变化的影响与水稻植物体的生长阶段有关;发现了水稻植物体(根、茎、叶)重量对CH4排放的重要作用.讨论了合理使用肥料和施肥量,控制水位和Eh值对稻田CH4的减排作用,提出优化组合诸影响因子,以充分发挥其减排潜力. 相似文献
10.
Thermal Climate Variations and Potential Modification of the Cropping Pattern in Bangladesh 总被引：1，自引：0，他引：1
R. Mahmood 《Theoretical and Applied Climatology》1998,61(3-4):231-243
Summary Changes in the thermal climate due to inter-annual climatic variability can potentially modify existing cropping pattern
by forcing farmers to rearrange transplanting and harvesting dates. In the present study, a crop climate model, the YIELD,
has been applied to 12 meteorological stations located in major rice growing regions in Bangladesh to estimate the effect
of thermal climate variations on the transplanting and harvesting dates of boro rice and the resultant potential changes in
cropping pattern and spatial shift. The abnormal thermal climate scenarios have been created by synthetically perturbing mean
air temperatures (Tair) up to −5 °C to +5 °C with an interval of 1 °C for each of these stations. Historical meteorological records of air temperature
in Bangladesh have been used to prepare these scenarios. The study finds that under abnormally cool conditions transplanting
dates will be pushed well into February to avoid plant injury and harvesting dates will be moved into the monsoon. The growing
seasons will be longer under cooler than normal thermal conditions. Under abnormally warm conditions harvesting dates will
be established well into March and will cause reduction of yield due to a shorter growing season. These conditions will also
cause spatial shift in crop potential and changes in the cropping pattern. Due to a longer boro rice growing season farmers
will lose a significant amount of cropping land which is usually used for low and deep water rice cultivation. New crops will
need to be introduced during the beginning of a year to overcome the loss of production under abnormally cool conditions.
Wheat and potato can be good options for the farmers for such conditions. New aus rice variety needs to be introduced after
the boro harvesting under warmer than the normal conditions to overcome the loss of yield due to a shorter growing season.
Received September 16, 1996 Revised September 8, 1997 相似文献
11.
Methane Production, Emission and Possible Control Measures in the Rice Agriculture 总被引：19，自引：0，他引：19
Wang Mingxing Shangguan Xingjian Shen Renxing Wassmann Reiner Seiler Wolfgang 《大气科学进展》1993,10(3):307-314
In the rice field methane is produced in the soil layer with depths of 2-25 cm. The vertical profile of methane production rate in the paddy soil during the water covering period differs from that in the paddy soil in dry phase. Only a small part, about 30%. of the produced methane is emitted to the atmosphere through rice plant, air bubbles, and molecular diffusion. Therefore, the methane emission rate from the rice field depends not only on the methane production rate in the soil, but also on the transport efficiency of the rice plant, air bubble formation that in turn depends on the production rate, and molecular diffusion.Field measurements show that methane emission rates from a particular rice field have very large diurnal, seasonal and interannual variations, which are related to soil characteristics, water regime, farming procedure, local climate, and rice growing activities. The relationship between the methane emission rate and the above mentioned factors is very complicated. The emission rate 相似文献
12.
13.
基于MODIS时序数据提取河南省水稻种植分布 总被引：1，自引：1，他引：0
以河南省为研究区,利用2009年多时相8d合成MODIS地表反射率产品提取水稻种植分布。根据稻田含水量变化特征及水稻生长规律,构建水稻种植分布提取流程。为减少云等噪声的影响,对地表水含量指数（ILSW,land surface water content index）和增强型植被指数（IEV,enhanced vegetation index）的时序数据进行平滑重建。然后,依据豫北和豫南稻区水稻物候期差异,分别建立标准水稻IEV生长线,以计算像元尺度的水稻相似性指数作为影像分类的特征波段。同时,对重建的ILSW和IEV时序数据分别进行主成份分析,选择各自的前3个成份作为特征波段。在此基础上,采用支持向量机分类算法对组建的特征波段进行分类,提取影像中水稻的种植分布。结果显示,提取的河南省水稻种植分布与实际情况吻合较好,豫北稻区水稻分布呈现集中连片的特征,多分布在沿黄河两岸,而豫南稻区水稻种植广泛,多在大型水库灌区周边及沿淮和低洼易涝地区。与各地区水稻统计面积相比,MODIS提取的水稻面积平均相对误差为6.56%,根均方误差为5.63khm2。受到混合像元影响,以及个别地区水稻种植分散且面积相对较小,使该地区水稻面积相对误差超过±60%。 相似文献
14.
Rosamond L. Naylor Walter P. Falcon Daniel Rochberg Nikolas Wada 《Climatic change》2001,50(3):255-265
Despite the strong signal of El Niño/Southern Oscillation (ENSO) events on climate in the Indo-Pacific region, models linking ENSO-based climate variability to seasonal rice production and food security in the region have not been well developed or widely used in a policy context. This study successfully measures the connections among sea surface temperature anomalies (SSTAs), rainfall, and rice production in Indonesia during the past three decades. Regression results show particularly strong connections on Java, where 55% of the country's rice is grown. Two-thirds of the interannual variance in rice plantings and 40% of the interannual variance in rice production during the main (wet) season on Java are explained by year-to-year fluctuations in SSTAs measured 4 and 8 months in advance, respectively. These effects are cumulative; during strong El Niño years, production shortfalls in the wet season are not made up later in the crop year. The analysis demonstrates that quantitative predictions of ENSO's effects on rice harvests can provide an additional tool for managing food security in one of the world's most populous and important rice-producing countries. 相似文献
15.
Climate change,the monsoon,and rice yield in India 总被引：4，自引：1，他引：3
Recent research indicates that monsoon rainfall became less frequent but more intense in India during the latter half of the
Twentieth Century, thus increasing the risk of drought and flood damage to the country’s wet-season (kharif) rice crop. Our statistical analysis of state-level Indian data confirms that drought and extreme rainfall negatively affected
rice yield (harvest per hectare) in predominantly rainfed areas during 1966–2002, with drought having a much greater impact
than extreme rainfall. Using Monte Carlo simulation, we find that yield would have been 1.7% higher on average if monsoon
characteristics, especially drought frequency, had not changed since 1960. Yield would have received an additional boost of
nearly 4% if two other meteorological changes (warmer nights and lower rainfall at the end of the growing season) had not
occurred. In combination, these changes would have increased cumulative harvest during 1966–2002 by an amount equivalent to
about a fifth of the increase caused by improvements in farming technology. Climate change has evidently already negatively
affected India’s hundreds of millions of rice producers and consumers. 相似文献
16.
Ashrafun Nahar Jeff Luckstead Eric J. Wailes Mohammad Jahangir Alam 《Climatic change》2018,150(3-4):289-304
Bangladesh, the sixth largest rice producer in the world, has been identified as high risk from the effects of climate change. Many of the adverse impacts of climate change such as land inundation and changes in weather patterns and CO2 levels will impact the agricultural sector. This study develops a partial-equilibrium multi-regional farm household model of Bangladesh rice and non-rice agricultural markets to quantify the impacts of climate change on consumption, production, prices, and farmers’ welfare. The model is calibrated to the Bangladesh rice market using Household Income and Expenditure Survey data. The model is simulated to analyze the impact of land reduction and productivity decline resulting from climate change. The results show that the decline in production in the coastal and northern regions offsets the production increase in the central and eastern regions, and the simulation predicts that total rice production for Bangladesh falls by about 2%. As total rice consumption falls and imports rise, the net effect leads to a rise in the rice price by 5.71% and a decline in farmers’ welfare. Sensitivity analysis shows that more- (less-) effective abatement technology could play a key role in mitigating (exacerbating) the price and welfare effects. The model predicts that many farmers in regions directly impacted by climate change could leave farming in search of off-farm work. Thus, the government can ease this transition by promoting urban development to provide more job options and technical training for farmers. 相似文献
17.
Climate change will influence yields while sea level rise can inundate producing lands. The research reported investigates the individual and simultaneous effects of these factors on production, trade and consumption of rice the world’s number one food crop. A global rice trade model is utilized to do this. The results indicate that the combination of yield and sea level effects causes a significant reduction in production and an increase in rice prices which may have important policy implications for food security. Global rice production is reduced by 1.60% to 2.73% while global rice price increases by 7.14% to 12.77%. Sea level rise is particularly a risk factor in Bangladesh, Japan, Taiwan, Egypt, Myanmar and Vietnam. In the face of such developments, adaptation may well be desirable and thus an investigation is done over adaptation options of increased technical progress or trade liberalization with the results showing that both can mitigate such damages. 相似文献
18.
稻曲病属于典型的"气象型"病害,为了提前预报出适宜稻曲病发生的气象等级与提供足够的防治准备时间,根据中长期天气预报原理,充分考虑大气环流和太平洋海温对区域气象条件影响的滞后性,利用近40 a的江苏逐日气象观测资料、大气环流指数和海温资料,采用空间拓扑原理和最优相关普查等统计方法,挑选出了对综合稻曲病指数影响最显著的预报因子,并通过滑动平均和主成分识别等检验方法确保预报因子的稳定性和独立性,最终分别建立了基于大气环流因子和基于海温因子的综合稻曲病指数长期预报模型。经过检验,两种模型的模拟效果均理想,能提前一个月预报出综合稻曲病指数以及对应的发病气象等级。 相似文献
19.
我国华中地区稻田甲烷排放特征 总被引：12，自引：1，他引：12
本文主要讨论地处我国华中水稻生态区的湖南红壤稻田的CH4排放特征。稻田CH4排放的日变化都有一致的规律，即在下午16:00左右出现最大值；CH4排放的日变化幅度与天气条件和水稻植物体有关；CH4排放的日变化与温度日变化的相关性很好（R>0.90）。早稻和晚稻的CH4排放季节变化规律有明显的差别，这主要是由于早、晚稻水稻生长期间的天气特别是空气温度变化的差异引起的，早稻CH4排放率在水稻生长中期（6月）略大，而晚稻在水稻移栽后几天内CH4排放就达到整个季节中的最大值，以后随时间逐渐降低；缺水会使CH4排放率明显降低，而且在重新灌水后相当长时间内CH4排放率没有回升；CH4排放在全有机肥的田中最大，然后依次是常规施肥、全沼渣肥及化肥田；尿素、氯化钾和复合肥的多施可降低稻田CH4排放率；不同施肥田中CH4排放率的温度效应不同；施肥是控制CH4排放的一种可行手段；在整个晚稻生长季节中瞬时CH4排放率与瞬时温度呈明显的指数关系；在1991年双季水稻生长季节中，稻田中CH4的排放量为67.96 g·m-2，其中早稻的CH4排放率为0.36 g·m-2·d-1，晚稻为0.48 g·m-2·d-1。 相似文献
20.
通过对建国以来安徽省多种农业气象资料分析，采用Z指数方法建立安徽省旱涝灾害气候判别指标，分析安徽省旱涝灾害发生规律。结果表明:1961—2000年安徽省有13年偏涝、13年偏旱；分区域看，淮北旱多于涝，沿淮、江淮、江南旱涝相当，沿江、大别山区涝多于旱。通过水稻（一季稻）、小麦典型旱涝年灾损率与发育期间气象条件、旱涝程度的对比统计分析，建立了分区水稻、小麦旱涝灾害损失评估模型和指标。春季涝渍灾害是影响安徽省冬小麦产量的主要灾害，其对冬小麦产量的危害程度远大于干旱，尤以4—5月发生的涝渍影响最严重，极重涝渍灾害的减产损失可达4成以上。同时重点研究了春季渍害对冬小麦产量的影响，提出改进的涝渍强度指标Qw，并进一步综合分析作物的敏感性和区域脆弱性对灾损率的影响。对1961—2000年冬小麦灾损率进行的敏感性和脆弱性订正表明，订正后拟合误差平均值和差异变率都明显降低，灾损评估精度得到提高。 相似文献