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1.
Changes in rice phenology during 1981–2009 were investigated using observed phenological data from hundreds of agro-meteorological stations across China. Spatiotemporal changes of rice phenology across China, as well as the relations to temperature, day length and cultivars shifts were analyzed and presented. We found that major rice phenological dates generally advanced while rice growing period changed diversely for different rice cultivation systems in different agro-ecological zones. Length of vegetative growth period (VGP) increased at 59 (67.0%) stations for single-rice, however, decreased at 36 (54.5%) and 35 (51.5%) stations for early-rice, and late-rice, respectively. Length of reproductive growth period (RGP) increased at 71 (70.3%) and 49 (55.7%) stations for single-rice and early-rice, respectively, however, decreased at 46 (54.8%) stations for late-rice. The changes were ascribed to the combined effects of changes in temperature, photoperiod and cultivar thermal characteristics. Increase in temperature had negative impacts on the lengths of VGP and RGP. Day length slightly counterbalanced the roles of temperature in affecting the duration of VGP. Furthermore, we found that during 1981–2009 cultivars with longer growth duration of VGP were adopted for single-rice, but cultivars with shorter growth duration of VGP were adopted for early-rice and late-rice. Cultivars with longer growth durations of RGP were adopted for single-rice and early-rice, as well as late-rice at the middle and lower reaches of Yangtze River. However, in the southwestern China and southern China, cultivars with shorter or almost same growth duration of RGP were adopted for late rice.  相似文献   

2.
木本植物物候特性在研究植物群落演替、生态系统物质循环及气候变化等方面具有重要意义。以且末地区杏树、银白杨、白柳、桑树和葡萄5种木本植物物候为研究对象,采用趋势分析、显著性检验、Mann-Kendall突变检测等方法,分析植物物候变化特性及其与气温的关系。结果表明:(1)物候期的变化特征为:杏树、银白杨、白柳、桑树和葡萄的展叶始期、始花期提前,叶色全变期推后,末花期、落叶末期各不相同。杏树、桑树和葡萄的生长季延长,银白杨、白柳略微缩短。(2)杏树、桑树和葡萄的物候特征变化较为显著,银白杨、白柳不显著。(3)植物物候变化的总趋势为:春季物候提前,秋季物候推后,生长季延长,与气温的变化趋势一致。  相似文献   

3.
Accurate modelling of plant development is the basis for any assessment of climate change impact on crop yields. Most rice models simulate development (phenology) based on temperature and photoperiod, but often the reliability of these models is reduced beyond the environment they were calibrated for. In our study, we tested the effects of relative air humidity and solar radiation on leaf appearance rate in greenhouse experiments and analysed data sets from field studies conducted in two extremely different rice-growing environments in Nepal and Senegal. We also analysed environmental effects on duration to flowering of one popular IRRI material (IR64) for eight different sites covering the entire temperature range where rice is widely cultivated. Both low relative air humidity and low solar radiation significantly decreased leaf appearance rate. Mean air temperature explained 81% of the variation in duration to flowering across sites, which was furthermore significantly influenced by relative air humidity. Across all sites, a simple linear regression approach including mean air temperature and mean relative humidity in the calculation of duration to flowering led to a root mean square error (RMSE) of 10 days, which was slightly lower than the RMSE of 11 days achieved with an automated calibration tool for parameter optimization of cardinal temperatures and photoperiod sensitivity. Parameter optimization for individual sites led to a much smaller prediction error, but also to large differences in cardinal temperatures between sites, mainly lower optimum temperatures for the cooler sites. To increase the predictive power of phenological models outside their calibration range and especially in climate change scenarios, a more mechanistic modelling approach is needed. A starting point could be including relative air humidity and radiation in the simulation procedure of crop development, and presumably, a closer link between growth and development procedures could help to increase the robustness of phenological models.  相似文献   

4.
With climate change posing a serious threat to food security, there has been an increased interest in simulating its impact on cropping systems. Crop models are useful tools to evaluate strategies for adaptation to future climate; however, the simulation process may be infeasible when dealing with a large number of G × E × M combinations. We proposed that the number of simulations could significantly be reduced by clustering weather data and detecting major weather patterns. Using 5, 10 and 15 clusters (i.e., years representative of each weather pattern), we simulated phenology, cumulative transpiration, heat-shock-induced yield loss (heat loss) and grain yield of four Australian cultivars across the Australian wheatbelt over a 30-year period under current and future climates. A strong correlation (r2≈1) between the proposed method and the benchmark (i.e., simulation of all 30 years without clustering) for phenology suggested that average duration of crop growth phases could be predicted with substantially fewer simulations as accurately as when simulating all 30 seasons. With mean absolute error of 0.64 days for phenology when only five clusters were identified, this method had a deviation considerably lower than the reported deviations of calibrated crop models. Although the proposed method showed higher deviations for traits highly sensitive to temporal climatic variability such as cumulative transpiration, heat loss and grain yield when five clusters were used, significantly strong correlations were achieved when 10 or 15 clusters were identified. Furthermore, this method was highly accurate in reproducing site-level impact of climate change. Less than 7% of site × general circulation model (GCM) combinations (zero for phenology) showed incorrect predication of the direction (+/−) of climate change impact when only five clusters were identified while the accuracy further increased at the regional level and with more clusters. The proposed method proved promising in predicting selected traits of wheat crops and can reduce number of simulations required to predict crop responses to climate/management scenarios in model-aided ideotyping and climate impact studies.  相似文献   

5.
气候及其变率变化对东北地区粮食生产的影响   总被引:21,自引:1,他引:20  
利用GISS、GFDL和UKMO 3种国际上通用的平衡大气环流模型(GCM)的有关输出值, 结合东北3大农业生态区19个样点近40年(1961—2000)的逐日气候资料(Baseline)以及未来气候变率变化(ΔCV)的3种假设, 并利用天气发生器(WGEN), 生成每个样点9种兼顾气候及其变率变化的(CC+ΔCV)情景; 选用DSSAT中的SOYGRO、CERES-Maize、CERES-Wheat和CERES-Rice作为效应模型, 并利用各样点的Baseline, 同期大豆、玉米、小麦和水稻的产量统计资料以及典型土壤资料, 对上述模型进行参数调试、可靠性检验和灵敏度分析; 将各效应模型分别在CC+ΔCV情景及Baseline下运行, 通过比较模拟结果, 就CO2有效倍增时气候及其变率变化对不同生态区粮食作物的影响做出定量评价。结果表明, 4种效应模型在研究区域均有较好的适应性, 其作为气候变化影响评价工具具有合理性; 气候变暖对东北大豆和水稻生产总体上有利, 尤其是在北部高寒区与东部湿润区, 模拟产量均明显提高, 但CC对玉米和小麦生产的影响以负面为主, 特别是玉米在各生态区不同情景下均表现为剧烈减产; 随着ΔCV增大, 雨育大豆、玉米和春小麦不仅模拟产量下降, 而且稳产性变差, 但对灌溉水稻影响不大。  相似文献   

6.
近10年浙江植被物候的遥感监测及时空动态   总被引:2,自引:1,他引:1  
为了全面认识浙江植被物候变化规律,进一步完善区域气候变化的植被响应机制,基于改进的Savitzky-Golay滤波算法重构了2001-2010年MODIS NDVI时间序列数据,利用分段多项式拟合和动态阈值法提取了浙江省近10年的植被重要物候期(生长季开始时间、结束时间和生长季长度),分析植被物候期的年际变化趋势和空间分异特征。结果表明:(1)浙江省植被生长季为3月下旬-11月中旬,平均生长季长度为222天。近10年的生长季开始时间有提前趋势,但提前不显著,结束时间显著推迟,生长季有所延长,每10年延长约7天。(2)浙江植被的生长季开始时间从北往南逐渐推迟,生长季结束时间相对集中。浙江植被生长季延长的区域面积和生长季缩短的区域面积相当。(3)不同植被类型物候特征差异较大,分析针叶林和灌丛草地2类典型样区植被的物候变化发现,灌丛草地NDVI的年内和年际变幅均较针叶林的大,且针叶林的平均生长季长度比灌丛草地短约35天,针叶林生长季有延长的趋势,而灌丛草地生长季变化不明显。  相似文献   

7.
民勤荒漠区36种植物物候期积温变化动因分析   总被引:1,自引:1,他引:0  
中国西北荒漠区植物物候随气温变暖表现为提前趋势。那么,在物候提前的过程中,是物候日数变化敏感呢,还是物候持续期积温变化敏感呢?变动的主要原因是什么?为了回答这个问题,本文以中国西北荒漠区36种植物34年的物候观测资料,利用一次趋势线方程、相关系数及其T检验等方法进行了分析。结果表明,随着气温升高,物候持续日数有不同程度的增长趋势,物候持续期的积温变化较物候持续日数变化敏感。积温的增减在很大程度上是由物候持续日数增加或减少引起的,其次才是由于气温增高引起的,这一点是其他相关研究文献未曾报道过的。年平均气温对物候持续日数的影响>物候开始当月平均气温>物候开始上月平均气温>物候持续期间平均气温和以及物候结束月平均气温。  相似文献   

8.
基于生理发育时间的水稻发育期预测方法   总被引:1,自引:0,他引:1  
水稻发育期模型研究是开展现代农业气象服务工作的基础。基于作物生理发育时间守恒原理,综合考虑温度和日长因子对水稻发育期的影响,利用云南省12个农气观测站2011—2014年水稻发育期观测和地面气象观测资料,分别构建并验证了适用于籼稻种植区和粳稻种植区的发育期预报模型。结果表明,2套模型在全发育期和各发育阶段的预报值与观测值模拟效果总体较好,平均全发育期RMSE值为7.47,RE值为7.99%,粳稻模型和籼稻模型的RE值分别为6.49%和9.5%,粳稻区模拟效果优于籼稻区。模型生物学意义明确、参数通用性强,适用于农业气象业务服务中水稻发育期预测,具有推广应用价值。  相似文献   

9.
Yield is influenced by the length of the growing season, which is affected by weather conditions and management practices of a crop, including sowing dates and shifting of cultivars. It is necessary to understand the effects of agronomic management practices and weather variables on phenological stages and crop phases in order to develop strategies for adaptation of agricultural systems to changes in climatic conditions. The goal of this study was to determine the impact of warming trends on phenology of canola from 1980 to 2014 for central and southern Punjab, Pakistan. Sowing, emergence, anthesis and physiological maturity dates were delayed by an average of 6.02, 3.14, 3.31 and 1.89 days per decade, respectively. The duration of sowing to anthesis, sowing to physiological maturity and anthesis to physiological maturity phases decreased an average 2.71, 4.13 and 1.42 days per decade, respectively, for all 10 locations that were analysed in this study. The sowing, emergence, anthesis and physiological maturity dates were positively correlated with an increase in temperature by an average 2.71, 1.41, 1.49 and 0.85 days per °C, respectively. However, the phenological phases such as sowing to anthesis, anthesis to maturity and sowing to maturity were negatively correlated with an increase in temperature by an average of 1.22, 0.64 and 1.86 days per °C, respectively, for all 10 locations. Applying a process‐based CSM‐CROPGRO‐Canola model using a standard cultivar (field tested) for all locations and years indicated that the simulated phenological stages occurred earlier due to the warming trend compared to the observed phenological stages. One‐quarter of the negative effects of this thermal trend was compensated by growing new cultivars that had higher thermal time requirements. Therefore, new canola genotypes with a higher number of growing degree day requirement and high temperature tolerance should be a priority for evolving new cultivars.  相似文献   

10.
Food security is a major concern in China due to increasing nutritional demands, limited resources, and a changing and uncertain climate. Rice (Oryza sativa L.) plays an important role in food security, whilst its yield is greatly influenced by climate change. Thus, it is critical to quantify changes in rice yield, determine the potential climatic conditions affecting yield variation, and identify strategies to counter the effects of climate change. Historical double-rice yields and climatic variables were analyzed in the major double-rice region of Southern China. Yield varied nonlinearly in most provinces, fluctuated more for late-rice, and exhibited stagnation in 1980–2012. During the growth stages, the mean temperature (Tmean) increased significantly at 75.1% of the stations examined (P < 0.05), while high inter-annual variation in precipitation (Prec) and radiation (Rad) decreased for 64.2% and 62.2% of stations. The joint effects of the three climatic variables increased yields of early- and late- rice by 0.51% and 2.83%, respectively. Climatic variation accounted for 40.04% and 29.72% of yield variability for early- and late-rice, respectively. Thus, double-rice production in Southern China is strongly affected by inter-annual climatic variation, requiring resilient farming practices to adapt to climate change and consequently enhance food security.  相似文献   

11.
为了探索陆地生态系统如何响应全球气候变化,基于植物物候遥感监测的原理和特点,笔者应用野外物候观测数据和植物物候遥感监测相结合的方法,采用中国国家气象局355个站点1951-2004年观测的相关资料,以及美国地球资源观测系统数据中心的探路者数据集中的NOAA/AVHRR NDVI数据,构建Logistic模型。将其应用于中国东部南北样带上以物候为指示的植被格局动态与气候变化研究之中,分析1982-2003年样带植被绿度期参量与降水相关关系。在全球气候变暖的情况下,植被绿度初期提前趋势明显,特别是在20世纪90年代中后期,平均绿度初期提前8天左右;样带北部温度升高、降水减少,特别是春季降水减少,会使温带荒漠地区荒漠化趋势加重。  相似文献   

12.
The aim of this research was to evaluate the variability of phenology and ripening characteristics of the Tempranillo variety within the Ribera del Duero Designation of Origin (Spain). This area covers approximately 115 km along the Duero River, where Tempranillo is the main variety cultivated. The analysis included the information recorded during the period 2004–2013 in 20 plots for phenology dates and 26 plots for grape characteristics. The variability in soil, phenology, grape quality and plot characteristics throughout the Ribera del Duero DO as well as their relationships were evaluated using multivariate analysis. Four different groups of plots were characterized as distinct from each other, with differences in elevation, distance to the Duero River and soil type. The differences in phenology among groups started during flowering and were observed through the end of the growth cycle. Despite the high phenological variability driven by year to year variations in climate characteristics, it was possible to define the soil and plot characteristics that favor advanced phenology within the Ribera del Duero DO. Regarding grape ripening characteristics, the highest acidity and anthocyanin concentrations were found in plots with soils with higher clay and organic matter content. The effect was greater in the wet and intermediate years, than in dry years. High variability in phenology and ripening characteristics is found within the Ribera del Duero related to site soil and landscape characteristics, and from year to year due to climatic conditions. Zones with common characteristics and similar response have been identified within the area. The results highlight the potential of establishing viticultural zones with differences in vineyard treatment and management and the elaboration of site specific wine styles from those zones.  相似文献   

13.
华北地区冬小麦产量潜力分布特征及其影响因素   总被引:5,自引:0,他引:5  
利用华北地区农业气象观测站作物资料,验证APSIM-Wheat作物模拟模型区域尺度有效性,结合1961-2007年47年逐日气候资料,分析冬小麦潜在产量、水分限制产量和水氮限制产量时空分布特征,明确了气候因素对冬小麦不同等级产量潜力分布特征的影响程度。对APSIM-Wheat模型在华北地区区域尺度上进行验证,结果显示区域化模型在华北地区有较好的适用性。华北地区冬小麦各层次产量在时间上总体呈下降趋势,空间上呈带状分布,不同层次产量空间分布特征有所差别:冬小麦潜在产量从东北向西南减少,水分限制产量从东南向西北递减,水氮限制产量从东向西先增加后降低在山东济宁地区达到最大;河北省为冬小麦潜在产量和水氮限制产量的高值区,同时为水分限制产量的低值区,增加灌溉是提高其产量的主要途径;山东省为冬小麦潜在产量和水分限制产量的高值区,水氮限制产量的低值区,增施氮肥是提高其产量的主要途径;河南省为冬小麦潜在产量的低值区,辐射是其主要限制因素。决定冬小麦潜在产量时空分布特征的最主要气候要素为生长季内总辐射,总辐射与潜在产量呈极显著正相关关系;决定冬小麦水分限制产量分布特征的最主要气候要素为冬小麦生长季内降水量,呈极显著正相关关系;气候要素对于冬小麦水氮限制产量空间分布特征的解释方差较小,仅为0.48,故土壤等其他因素对其空间分布影响较大。气候变化背景下,如不改变作物品种,冬小麦各级产量潜力呈下降趋势,造成其下降的主要原因为总辐射下降以及随积温增加冬小麦生长季缩短,决定冬小麦产量潜力空间分布的主要因素为总辐射和降水量。  相似文献   

14.
The Northeast Farming Region of China (NFR) is a very important crop growing area, comprising seven sub-regions: Xing’anling (XA), Sanjiang (SJ), Northwest Songliao (NSL), Central Songliao (CSL), Southwest Songliao (SSL), Changbaishan (CB) and Liaodong (LD), which has been severely affected by extreme climate events and climatic change. Therefore, a set of expert survey has been done to identify current and project future climate limitations to crop production and explore appropriate adaptation measures in NFR. Droughts have been the largest limitation for maize (Zea mays L.) in NSL and SSL, and for soybean (Glycine max L. Merr.) in SSL. Chilling damage has been the largest limitation for rice (Oryza sativa L.) production in XA, SJ and CB. Projected climate change is expected to be beneficial for expanding the crop growing season, and to provide more suitable conditions for sowing and harvest. Autumn frost will occur later in most parts of NFR, and chilling damage will also decrease, particularly for rice production in XA and SJ. Drought and heat stress are expected to become more severe for maize and soybean production in most parts of NFR. Also, plant diseases, pests and weeds are considered to become more severe for crop production under climate change. Adaptation measures that have already been implemented in recent decades to cope with current climatic limitations include changes in timing of cultivation, variety choice, soil tillage practices, crop protection, irrigation and use of plastic film for soil cover. With the projected climate change and increasing risk of climatic extremes, additional adaptation measures will become relevant for sustaining and improving productivity of crops in NFR to ensure food security in China.  相似文献   

15.
为探究两系杂交稻两优培九粒重对气候的反应和生态适应性,用2006年和2007年在南方稻区8个生态点29点次的田间种植试验资料,将粒重解析为谷粒长、宽、厚和比重4个因子,组建了谷粒面积(S)、厚度(H)和比重(ρ)的环境预测模型。相关分析表明,谷粒面积S的影响期在颖花分化期(III~IV期)至花粉母细胞减数分裂期(VI~VII期),温度是其主要影响因子,有利于谷粒长度和宽度发育的日平均气温( )为27~29℃,最高气温(Tmax) 34℃,最低气温(Tmin) 24℃。谷粒厚度H与抽穗后1~30 d的Tmax呈二次曲线关系,与 呈负相关。谷粒比重ρ与日照时数(SH)呈正相关,影响时期在抽穗后1~10 d;与Tmax呈负相关,影响时期在抽穗后1~30 d。有利于增加ρ的气象指标是SH达到8 h,Tmax低于30℃。用1951—2002年的气候资料模拟计算了95个地区的两优培九千粒重,按7个水稻生态区归纳,平均值变化在25.93~28.01 g之间。千粒重的区域分布明显随纬度而递增,由于地形影响,在湘、赣、粤北地区还表现出一定的经向影响。晚季稻的千粒重则比早季稻高1.39 g。幼穗分化期的温度和灌浆结实期的温度、日照时数是造成两优培九粒重区域和季节特征的主要生态原因。  相似文献   

16.
新疆棉花物候期对气候变化的响应及敏感性分析   总被引:1,自引:0,他引:1  
为了研究气候变化背景下棉花物候的变化规律,对棉花生长模型COSIM进行参数调校,验证实现本地化,利用数理统计及作物模型模拟的方法,分析了棉花物候期对气候变化的响应及其敏感性。结果表明:1980—2019年,新疆棉区棉花出苗期、现蕾期、开花期分别提前0.5~7.0 d/10a、0.1~5.8 d/10a、0.3~3.9 d/10a,吐絮期推迟0.1~4.7 d/10a。COSIM模型模拟棉花物候变化趋势结果与实际较一致,出苗期、现蕾期、开花期、吐絮期实际值与模拟值的RMSE分别为0.9、0.7、0.6、0.7天。以1981—2010年气候条件为基准,增温0.5℃、1℃、1.5℃、2℃,各棉区棉花出苗期、现蕾期、开花期和吐絮期分别提前0~2天、1~9天、2~12天和3~31天,营养生长、生殖生长分别缩短0~6天、2~22天。在气候变暖的趋势下,通过选择生育期较长的品种、调整播期等措施,可充分利用热量资源,实现棉花优质高产。  相似文献   

17.
气候变化对水稻病虫害发生发展趋势的影响   总被引:5,自引:2,他引:3  
摘要:以贺州市为例,利用其近20年来地面气象观测站气候资料及贺州市八步区植保站相应年份水稻病虫害资料,通过回归相关分析等统计方法,得出相关密切的几大气候因子,分析其历年来变化对水稻病虫害发生发展趋势影响。结果表明:冬季最低温度等主要6项气候因子影响贺州市水稻病虫害发展趋势,且6项气候因子的变化均有利于水稻病虫害发展加剧,即随着气候变化,贺州市水稻病虫害有不断加剧严重趋势。  相似文献   

18.
气候变化对中国水稻生产的影响研究进展   总被引:12,自引:0,他引:12  
水稻生产系统是响应气候变化最敏感的农业生态系统之一,本文综述了当前和未来气候变化对我国水稻生产的影响。气候变化背景下,我国水稻生长季的热量资源增多,辐射资源减少,降水不均一性加大。高温热害、干旱、暴雨和洪涝灾害发生更频繁,这可能降低水、热资源的有效性。气候变化使我国单季稻和双季稻潜在种植边界显著北移,导致单季稻、早稻和晚稻的主要生育期缩短。基于统计模型和水稻生长模型的研究结果表明,如果不考虑品种改良和栽培技术的进步,气候变化使单季稻、早稻和晚稻产量下降,但不同稻作区和方法间存在差异。我国水稻生产重心北移、实测生育期延长和产量增加的变化趋势,反映了水稻生产系统通过种植分布调整、品种改良和技术改进来适应气候变化的能力。未来气候变化将进一步导致水稻生育期缩短和产量下降,对我国水稻生产和粮食安全带来严峻挑战。仍需加强气候变化影响机制的研究及其在影响评估中的应用,减小影响评估的不确定性并增加其系统性,为制定有效的应对策略提供可靠的理论支持。  相似文献   

19.
利用气候倾向率、降水相对变率,划分基准年方法,研究近60年朝阳地区玉米生长季及各个发育期降水变化特征。结果表明:近60年玉米生长季降水量气候倾向率为-6.55mm /10 a,呈下降趋势。玉米各生育期降水变化趋势不同,玉米播种—苗期、成熟期的降水量呈增加趋势,气候倾向率分别为 4.2 mm/10 a和0.3 mm/10 a,拔节—孕穗期的降水量呈下降趋势,气候倾向率为-10.6 mm /10 a。不同基准年降水变化趋势差异显著,第Ⅱ基准年降水减少最明显,气候倾向率达-23.7 mm/10 a。第Ⅲ基准年降水增加最明显,气候倾向率达29.0 mm/10 a。朝阳地区玉米生长季及各个发育期降水相对变率大,降水偏少年最多,正常年最少。研究结果为该地区玉米生产良种选择、栽培方式改进及趋利避害、防灾减灾等提供气候依据。  相似文献   

20.
基于MaxEnt模型湖南双季稻种植气候适宜性分布研究   总被引:2,自引:0,他引:2  
通过查阅了相关文献资料,选取了适宜湖南水稻种植分布8个潜在的气候因子和湖南17个双季稻农业气象观测站点位置信息,利用MaxEnt模型,构建了湖南杂交水稻潜在种植分布与气候因子关系模型,得出影响湖南水稻种植的主要气候因子,以及湖南水稻适宜性种植分布区域。结果表明:10~22℃活动积温、4—10月日照时数、稳定通过22℃持续日数、4—10月降水量为影响种植湖南双季杂交稻主导气候因子。并进一步通过得到的主导气候因子,采用MaxEnt模型再次进行湖南双季杂交水稻适宜种植性分区,将湖南省双季稻制种植分布划分为:最适宜区、适宜区、低适宜区和不适宜区。本研究的主要目的是在省级层面上利用MaxEnt模型筛选影响湖南水稻种植主导气象因子,并对湖南水稻适宜性种植分布做了不同等级划分,为优化湖南双季杂交稻生产布局、改进种植制度和确保粮食生产安全提供了一定气象参考依据。  相似文献   

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