黑龙江省大豆主产地产量动态预报系统的建立

利用黑龙江省大豆主产区农业气象试验站产量资料和发育期资料,日最高气温、最低气温、日降水量和日照时数等资料,根据历史相邻两年关键气象因子变化引起大豆产量的丰欠指数,建立动态产量预报模型,并在已建立预报模型的基础上,以Visual Basic 6.0为计算机语言开发黑龙江省大豆产量动态预报系统。结果表明:经2011-2013年大豆产量动态预报检验,5个代表站81%的大豆预报结果丰欠趋势与实际趋势表现一致,单产预报准确率总体较好,越接近大豆成熟,预报准确率越高;经2016年业务运行,预报系统可以方便、快捷地实现对黑龙江省主产区大豆产量的动态预报。     

基于关键气象因子的辽宁省水稻产量动态预报

利用辽宁省33个气象站点1993—2012年水稻产量、生育期内的旬平均气温、旬降水量及旬日照时数等资料,应用统计分析方法建立水稻的产量动态预报模型。使用5年滑动平均法分离水稻趋势产量,分析气象产量与水稻生育期内逐旬气象要素的相关性,确定5月上旬平均气温、5月下旬平均气温、6月下旬降水量、7月下旬降水量、8月上旬日照时数、9月中旬平均气温和9月下旬日照时数为关键气象因子,建立水稻产量动态预报模型,并对预报结果进行验证。结果表明:对1993—2012年进行模拟预报及回代检验,平均准确率在93%以上;对2013年的产量进行预报,准确率为93.97%~99.67%,预报准确率较高。预测结果基本可以反映水稻产量的变化情况,能够满足业务服务的需要。     

基于气候适宜度指数的吉林省大豆单产动态预报研究

为及时、准确地进行大豆产量预报,给相关部门提供可靠依据保障吉林省粮食安全,利用吉林省1980-2016年大豆产量、生育期、逐日气象数据,基于大豆生长发育的生物学特性(最适温度、上限温度、下限温度、需水量、需光性等),构建大豆生长季逐旬温度、降水、日照时数及综合气候适宜度模型,通过与相对气象产量进行相关和回归分析,建立基于气候适宜度指数的7-8月逐旬产量动态预报模型,对吉林省大豆产量进行动态预报。结果表明:各时段建立的产量预报模型均通过0.05水平的有效性检验,能够客观反映大豆生长期内气象要素状况;各预报模型的历史回代检验平均准确率均大于85.0%,均方根误差小于20.0%;历史回代拟合的气象产量与实际气象产量在年际变化上具有较好的一致性,两者相关性通过0.05水平的显著性检验;在1981-2014共34年中各旬单产趋势预报准确的年份均在24年以上。各时段预报模型对2015-2016年的外推预报准确率分别在92.0%和81.4%以上,趋势预报不稳定,可能与模型没有考虑灾害影响有关。总体上,构建的产量预报模型可为吉林省大豆产量预报提供参考依据。     

巴西大豆产量预报方法研究

利用1961～2007年巴西大豆平均单产资料、西太平洋月平均海温、北半球500 hPa平均高度场环流资料以及巴西大豆种植区域代表气象站的逐日气温资料,建立了基于海温、环流资料和基于地面气象要素的巴西大豆产量预报模型.利用3种模型分别对1996～2005年巴西大豆平均单产进行预报检验;综合3种模型的模拟效果,利用加权方法建立了巴西大豆产量预报集合模型.1996～2005年预报检验和2006～2007年预报试验的准确率基本都在90%以上,能够满足业务服务的需要.     

基于气候适宜度预报内蒙古大豆发育期及产量

开展作物发育期及产量预报对农业生产和粮食安全具有重要意义。本文选取1981-2012年大豆生长季 气象数据和发育期资料，结合生理指标，构建大豆气候适宜度模型，建立适用于内蒙古地区的发育期预报模型及以 旬为步长的产量预报模型，并应用2013-2015年资料进行预报检验。基于气候适宜度的大豆各发育期持续天数预 报模型均通过0.01极显著水平，准确率除鼓粒—成熟期稍低外，其余均在90%以上，模型预报精度较高；产量动态 预报模型大部分时段均通过显著性检验，基于气候适宜度法的10个代表站预报平均准确率为87.6%。文章基于气 候适宜度法建立的发育期及产量预报模型均能满足业务服务的需求，可供其他大豆主产区的发育期及产量预报方 法研究借鉴。     

大豆产量动态预报模型研究

近年来,受进口大豆的冲击,中国大豆产业面临着严重挑战.为了给政府决策提供可靠的依据、保障中国粮食安全,每年能准确地进行大豆产量预报具有重要意义.利用大豆不同生育阶段气象因子的综合聚类指标选择气象相似年型,再根据相似年的产量变化确定预报年的产量气象影响指数,建立全国大豆单产动态预报模型.通过对1995-2004年大豆产量进行动态预报,结果表明:5月31日、6月30日、7月31日、8月31日和9月30日大豆产量预报准确率分别为97.0%、93.8%、94.9%、93.7%、95.1%,实现了大豆产量的连续、动态、定量预报.     

应用数学模型研究上海县油菜生产力的变化

为了定量分析诸科技因子与自然因子对上海县1955—1988年油菜生产力发展变化的贡献和作用,建立了油菜生产力的专家模型、道格拉斯模型和趋势产量模型。研究结果表明,趋势产量于1978年达峰值。1978年比1955年每亩趋势产量提高72.9公斤,增产132％。其中,品种更换、栽培技术改进、施肥水平与地力变化和三因子综合作用对产量增长的贡献分别占54％、36％、15％和27％。1988年比1978趋势产量下降24.3公斤,减产19％。四者对产量变化的作用分别为1.6％、-6.4％、-7.2％和-7.0％。筛选出对当地脉动产量构成较大影响的7项气候指标,其综合丰歉指数的变幅达40％—-60％,丰年平均增产率为27.2％,歉年平均减产率为22.6％。对脉动产量产生较大影响的病虫危害年,大体上三年一遇,平均减产指数为5.7％,个别严重危害年的减产指数可达30％。     

芝麻产量气象模式研究

本文将芝麻历史产量分解为趋势产量与气象产量两个分量,并将气象产量变换为气象产量指数,通过多重非线性回归模拟,建立了气象产量指数及产量模式,从而揭示芝麻产量动态趋势及年际变化原因。其结果,可用于鉴定芝麻生育期间的农业气候条件,为芝麻趋利避害与高产稳产提供依据,并可用于产量的预测预报。 本文采用安徽淮北平原阜阳县历年芝麻单产及相应年份的气象资料。五十年代,由于春、夏芝麻并行,六十年代起以夏芝麻为主,故五十年代产量资料舍去不用。现将研究结果分述如下:     

利用天气促病指数预报水稻纹枯病发病趋势

从水稻纹枯病生物学特性出发,综合分析耒阳市近19年水稻纹枯病发生程度及气象资料,筛选满足水稻纹枯病病菌侵入寄主的气象因子条件,即纹枯病促病气象指标:日平均气温23～30℃、日平均相对湿度≥86％(其中早稻日平均相对湿度≥91％)、日照时数≤2 h、日降水量＞1 mm,建立了水稻纹枯病发病的气象条件促病指数Z.运用数据分析软件DPS对天气促病指数与纹枯病发生等级进行相关分析,确立了纹枯病发病的气象条件预报等级指标.通过1991～2009年历史回代检验,历史符合率为61％,预报可行性较好.     

生物炭施用对早稻产量形成的影响

为探明生物炭施用对早稻产量形成的影响,以中早39为材料,于2015年和2016年早季在湖南省浏阳市永安镇开展大田试验,在不同施氮水平下(N0,0 kg N/hm~2;N1,90 kg/hm~2;N2,150 kg N/hm~2)对施炭(C1,20 t/hm~2)和不施炭(C0,0 t/hm~2)处理早稻的产量、产量构成、干物质生产和收获指数进行了比较。结果表明,除2015年N1水平外,C1处理的产量均低于C0处理,其中,2016年C1处理的平均产量比C0处理低12.85%;2015年和2016年C1处理的千粒重分别比C0处理低2.46%~4.12%和2.55%~3.76%;齐穗后C1处理干物质生产量高于C0处理,但其收获指数低于C0处理,2015年和2016年C1处理与C0处理的收获指数最大相差5.33个和4.00个百分点。由此可见,施用生物炭显著降低了早稻千粒重和收获指数,进而导致早稻减产。     

Improved Yield Prediction of Ratoon Rice Using Unmanned Aerial Vehicle-Based Multi-Temporal Feature Method

Pre-harvest yield prediction of ratoon rice is critical for guiding crop interventions in precision agriculture.However,the unique agronomic practice(i.e.,varied stubble height treatment) in rice ratooning could lead to inconsistent rice phenology,which had a significant impact on yield prediction of ratoon rice.Multi-temporal unmanned aerial vehicle(UAV)-based remote sensing can likely monitor ratoon rice productivity and reflect maximum yield potential across growing seasons for improving the ...     

Higher crop performance of rice hybrids than of elite inbreds in the tropics: 2. Does sink regulation,rather than sink size,play a major role?

Higher harvest index, widely reported as a main trait supporting major improvements in rice yield potential, also supports the higher performance of hybrids over inbreds. Although higher sink size is generally claimed for being the driver of higher grain filling in hybrid rice, it is relevant to question whether efficient sink regulation, that is timing and magnitude of the successive sink activities over crop growth from early stage, plays a role in supporting higher harvest index and is a key feature ensuring higher performance of hybrid rice. The partitioning coefficient (PC), as the increase in dry matter of one single organ over that of shoot, was calculated over short and successive periods to quantify the dynamics of dry matter partitioning. Four hybrid and four inbred genotypes of similar crop duration were grown under the same cropping management on the IRRI farm during a wet and a dry seasons. While PC to blade and sheath was similar for both plant types in both seasons at the early stage, PC to culm of hybrids was higher than that of inbreds, and PC to blade was lower, in the late vegetative and early reproductive phases. During the late reproductive phase, PC to panicle of hybrids was higher than that of inbreds, and PC to culm was lower whereas culm elongation was similar for both plant types. During grain filling, PC to culm was significantly more negative with hybrids which indicated stronger remobilization with hybrids. Specific culm length before anthesis, as low as 40 cm g⁻¹, accounted for storage ability, and at maturity, as high as 130 cm g⁻¹, for remobilization ability. Sink strength index, as a better indicator of dry matter partitioning efficiency than harvest index, and unfilled grain size, as an indicator of assimilate wastage, were suggested as key indices to account for the better sink regulation in hybrid rice and to improve screening protocols for increasing yield potential and tolerance to lodging.     

超级杂交中籼水稻物质生产特性分析

以具代表性的5个籼型超级稻为材料, 用汕优63作对照, 比较研究了超级中籼杂交稻物质生产与分配的特性。 超级稻具有显著的物质生产与积累优势, 产量随成熟期物质积累量的增加而提高。 超级稻的物质生产优势集中在中期和后期, 产量与拔节前的干物质积累量相关不显著, 与拔节至抽穗期的积累量呈显著正相关, 与抽穗至成熟期的干物质积累量呈极显著正相关; 超级稻抽穗期营养器官贮存了较多的结构物质但干物质表观输出量均低于对照, 平均少148.5 kg/hm2, 表观输出率也低, 平均低2.5个百分点。 超级稻的叶面积及光合势的显著提高促进了群体生产率的提高, 大田期平均群体生产率比对照高4542 (m2·d)/hm2。     

利用无人机图像颜色与纹理特征数据在小麦生育前期对产量进行预测

为了实现基于无人机的小麦产量快速预测,通过不同种植密度、氮肥和品种的田间试验,应用无人机航拍获取小麦生育前期（越冬前期和拔节期）的RGB图像,通过图像处理获取小麦田间颜色和纹理特征指数,并在小麦收获后测定实际产量。通过分析不同颜色和纹理特征指数与小麦产量的关系,筛选出适合小麦产量预测的颜色和纹理特征指数,建立小麦产量预测模型并进行验证。结果表明,小麦生育前期图像颜色指数与产量的相关性较好,而纹理特征指数相关性较差。对越冬前期利用单一颜色指数NDI构建的产量预测模型验证时,R为0.541,RMSE为671.26 kg·hm^-2;对拔节期用单一颜色指数VARI构建的产量预测模型验证时,R为0.603,RMSE为639.78 kg·hm^-2,预测结果比较理想,但不是最优。对越冬前期颜色指数NDI和纹理特征指数ENT相结合构建的产量预测模型验证时,R和RMSE分别为0.629和611.82 kg·hm^-2,比单一颜色指数模型分别提升16.27%和减小8.85%;对拔节期颜色指数VARI和纹理特征指数COR相结合构建的产量预测模型验证时,R和RMSE分别为0.746和510.29 kg·hm^-2,较单一颜色指数模型分别提升23.71%和减小20.24%。上述结果说明,将无人机图像颜色和纹理特征指数相结合建立的估产模型精度较高,可在小麦生育前期对产量进行有效预测。     

单季稻区蜘蛛群落的研究——多样性,优势度,排序和聚类

 1987～1988年对江苏省江浦县和安徽省铜陵市两地单季稻区蜘蛛群落进行了调查研究。蜘蛛群落组成共45种，分属于25属10科。群落主要成分是食虫沟瘤蛛Ummeliata insecticeps、草间小黑蛛Erigonidum graminicolum、拟水狼蛛Parata subpirapicus、拟环纹豹蛛Pardosa pseudoannulata，个体数以食虫沟瘤蛛占优势。冬作田中以油菜田的蜘蛛群落多样性、均匀度较高。从时间上，稻田蜘蛛群落多样性值在水稻移栽42 d(6月24日)和92 d(9月21日)分别达到高峰，其值分别是3.68531和3.96823，多样性值在水稻生长中后期高于前期，优势集中性指数则相反。从空间上看，迟栽田多样性、均匀度，丰富度高于早栽田，而优势度则相反：迟栽田的群落稳定性高于早栽田。对两地区蜘蛛群落进行排序和模糊聚类分析，表明群落组成的相似性与水稻移栽期关系密切，总体上看稻田蜘蛛群落组成的异值水平较小，不同地区不同年份稻田间蜘蛛群落的差异比同地区相同年份的大。移栽期相同的稻田蜘蛛群落在阈值水平λ很高时就可归为一类。     

Crop water stress index for potato under furrow and drip irrigation systems

Summary This study was conducted to determine the crop water stress index (CWSI) for potato (Solanum tuberosum L.) grown under furrow and drip irrigation methods and subjected to three different irrigation levels (100, 50 and 0% replenishment of soil water depleted). The lower (non-stressed) and upper (stressed) baselines were determined empirically from measurements of canopy temperatures, ambient air temperatures and vapor pressure deficit values. Tuber yield decreased when mean CWSI prior to irrigation exceeded 0.68 in furrow and 0.81 in drip irrigation. The tuber yield was directly correlated with the seasonal CWSI values and the linear equations for furrow and drip irrigation methods, Y = −45.82 CWSI + 50.69 and Y = −52.65 CWSI + 58.44, respectively, can be used for yield prediction.     

前氮后移对杂交中稻及其再生稻产量的影响

以20个杂交中稻组合为材料,在前氮后移与重底早追两种施氮方式下,研究了前氮后移对头季稻及再生稻产量的影响。结果表明,前氮后移有助于提高杂交中稻组合头季稻及再生稻产量,且高于重底早追施氮方式,但各杂交组合间表现各异。其中,内5优306、蓉18优447、德香4103、内5优317和川谷优7329这5个组合前氮后移处理头季稻比重底早追处理显著或极显著增产,乐优198、宜香优800、蓉优1808、冈比优99、冈优725、德香4103、炳优900、F优498、内5优317这9个组合的再生稻产量前氮后移处理比重底早追处理高。综合考虑头季稻产量和再生力,两季总产较高的组合为宜香优800、内5优317和蓉18优447。     

Geostatistical Analysis of Yield,Soil Properties and Crop Management Practices in Paddy Rice Fields

Abstract

We examined the possible benefit of rational site-specific crop management practices in 17 paddy fields located in an area of 2.0 ha for the prevalence of precision agriculture methods on a cooperatively managed large-scale farm in Sakurai, Nara Japan. Data on grain yield, soil physicochemical properties and farmer's crop management practices were collected in each paddy field. Unhulled rice yield was estimated at a resolution of 5m ? 5m in an area of 1.2 ha using a yield-monitoring combine. The spatial distribution of the variations for the collected data was characterized using geostatistical procedures. The kriged map of the unhulled rice yield drawn from the results of geostatistical analysis indicated the potential value of rational site-specific crop management using the yield-monitoring combine. The ratio of spatially structured variation to the total variation of brown rice yield, that is, the controllable proportion to total variation, was 75.4%. Each yield component i.e., the number of spikelets per square meter, filled-spikelet percentage and 1000-grain weight contributed 33.7%, 54.7% and 11.6%, respectively, to brown rice yield. These three yield components combined contributed to 96.5% of the brown rice yield variation. The agronomic factors (soil fertility factor, early growth factor, N dressing and uptake factor) contributed 79.7%, 52.1% and 41.8%, respectively, to the variation of these three yield components. Therefore these agronomic factors accounted for 58.1% of the total variation of the brown rice yield and 77.1% (i.e. 58.1% out of 75.4%) of the spatially structured variation of the brown rice yield. This controllable proportion may be a criterion for the prevalence of site-specific crop management in large-scale farm management in general, although only one case study was conducted.     

Comparison of conventional puddling and dry tillage in rice–wheat system

In many parts of Asia, rice is transplanted in puddled fields and after the harvest of this crop wheat is grown. This traditional method of growing rice may have deleterious effect on the growth of the subsequent crop in a rice–wheat cropping system. Wheat crop was planted in the same plots following a rice crop to evaluate the residual effects of various tillage treatments suitable for rice on the growth of the subsequent crop. Rice cultivar Super-basmati was grown in summer and wheat cultivar Auqab-2000 in autumn after rice. Four treatments were used to grow rice viz. transplanting in continuously flooded conditions (TRF), transplanting with intermittent flooding and drying (TRI), direct seeded using dry seeds (DSR) and direct seeded using primed seeds (DSP). Traditional puddling tillage system was followed in TRF and TRI, while for DSR and DSP, dry tillage system was followed. For convenience, the abbreviations of the rice treatments were used to indicate the same plots during the wheat crop. For the rice crop, tiller number, fertile tillers, kernel and straw yield, and harvest index were significantly better with transplanted treatments (TRI and TRF) than the direct seeded treatments. TRI also gave a yield advantage of 5% over TRF. For wheat, crop following direct seeded rice was better than transplanting. This study suggests that intermittent irrigation in the traditional puddling tillage system and DSP dry tillage system are the promising alternatives that may be opted.     

基于无人机遥感的水稻产量估测

水稻产量的准确估算在农业生产中具有重要意义。本文通过无人机搭载多光谱传感器,获取水稻主要生育期冠层光谱信息,通过提取不同生育期8种植被指数与水稻产量的实测值建立拟合关系,筛选出最优植被指数和最佳的无人机遥感作业时期,建立水稻估产模型。结果表明,水稻生长前期不适合估产,抽穗期至成熟期估产效果好。最佳估产生育期是水稻抽穗期,基于该时期的植被指数NDVI、RVI、DVI、GNDVI、MSAVI2建立的多元线性模型估测效果较好,验证精度佳。因此,利用无人机多光谱数据对水稻产量进行估测是可行的。