碳汇林主要建群种树高和胸径生长模型构建

依据湖南省碳汇林的主要类型,利用"八五"到"十二五"期间课题组自有研究成果,并进行补充调查;以碳汇林的17个主要建群种作为研究对象,综合考虑林分类型、立地状况、群落结构等因子布设固定样地194个,按径阶组划分不同的树高级用以选取目标径阶标准样木共计1 098个,采用树干解析木法,利用Richard、Logistic、Korf、Mitscherlich、Schumacher、Weibull等6种理论生长方程分别进行拟合。得出拟合效果最优的主要建群种树高和胸径生长模型,所有最优模型相关系数均达到了0.9以上,通过评价与检验,各模型均具有较好的拟合精度和预估水平。     

不同种植方式对水稻颖花穗部分布的影响

为研究在不同种植方式下水稻穗颖花量的变化特征,设置4种不同田间种植方式,研究水稻稻穗颖花特征。试验发现:(1)稻穗颖花由穗基部向穗顶方向在稻穗呈抛物线型分布,穗中部颖花量最大;(2)随着单株水稻稻田生态空间增加,稻穗颖花总量及穗上、中、下部颖花量分别增加;稻穗一次枝梗数及其颖花量无明显增加;稻穗二次枝梗数及其颖花量和稻穗中、下部二次枝梗数增加及稻穗上、中、下部二次枝梗颖花量显著增加,其中杂交稻表现穗中、下部二次枝梗数增加,常规稻仅为穗中部二次枝梗数增加;(3)单株水稻颖花量与其籽粒重显著正相关(R~2=0.804)。研究结果表明不同种植方式对水稻颖花穗部分布影响主要表现在二次枝梗数总数及分布在穗中、下部位的二次枝梗数,和二次枝梗的颖花量及其在穗的下、中、上部位的分布数量。     

不同氮素累积量类型籼稻品种有关源库指标的基本特点

2001、2002年,在群体水培条件下,分别以国内外的籼稻代表品种88个和122个为材料,于抽穗期和成熟期测定植株的干物重（包括根系）、全氮含量及产量,采用组内最小平方和动态聚类方法对供试品种成熟期的氮素累积量进行聚类,分析不同氮素累积量类型籼稻品种间有关源库指标的特点。结果表明,供试品种成熟期氮素累积量差异很大,可聚类为A、B、C、D、E、F等6类,类型间的差异均达到了显著水平。高氮素累积量类型籼稻品种有关源库指标的基本特点为：抽穗期和成熟期叶面积系数大、结实期叶面积系数减少量大、结实期叶面积系数减少比例较低、抽穗期单位面积绿叶重大、比叶重高、结实期净同化率较高、单位面积颖花量和库容量大。     

玉米不同穗型品种粒、叶内源生理特性的群体调节研究

采用系统聚类的方法对我国20世纪80年代以来的50个主栽玉米品种进行划分,通过密度调控,对不同穗型玉米品种粒、叶内源生理特性进行了深入探讨,试验结果如下:各穗型玉米品种同一生育时期相比较,叶片的功能强弱依次为紧凑大穗型品种掖单13、紧凑小穗型品种掖单4号、平展大穗型品种沈单7号.密度对不同穗型玉米品种叶片生理的影响     

基于影子价格法的碳汇渔业碳补偿额度分析——以山东海水贝类养殖业为例

本文通过影子价格法建立了碳汇渔业碳补偿额度模型,以山东海水贝类养殖业为例,计算了2001-2009年的海水贝类养殖业的碳补偿额度。从2001年到2008年,山东海水贝类养殖业碳补偿额呈上升趋势,2008年到2009年呈轻微下降趋势。经济的增长、物价的上涨、生态环境的恶化以及人们对生活要求的提高等是促使碳补偿额度上升的原因,2008年山东近海海域生态环境的好转是其碳补偿的资金额度略有下降的主要原因。总体来说,碳补偿需求越来越大,应得到更多重视。转变传统渔业养殖的成本收益观念,建立全国范围的碳补偿基金等是保证碳汇渔业碳补偿合理发展的策略。     

水稻计算机模拟模型及其应用之六 长江流域水稻穗粒结构的气候生态特征及库源关系协调性分析

本文应用以下模型或子模型:(1)有效穗数子模型,(2)每穗粒数子模型,(3)结实率子模型,(4)生育期“水稻钟”模型,(5)群体光合生产(或“源”产量)模型,(6)“库”产量模型,对不同品种或品种类型水稻的穗粒结构在长江流域的气候生态特征和“库”、“源”产量的协调性特征进行了数最分析。分析结果对于评价不同品种或类型的水稻在长江流域的气候适应性,找出限制产量的气候因素,指出增产途径和制定生产对策具有重要价值。最后还利用长江流域水稻气候生态鉴定试验(1985～1986)的有关资料对上述分析结果进行了验证和评价。     

水稻计算机模拟模型及其应用之五 估算水稻产量成分和库产量的模拟模型

根据长江流域优质、高产水稻新品种气候生态鉴定试验(1985～1986)的穗粒资料和同期气象资料,分别对单位面积上的有效穗数、每穗粒数和结实率的形成建立了相应的数学模型。决定有效穗数的重要气象因子是分蘖期的日照百分率和平均温度。决定每穗粒数的重要因子是出苗一抽穗的生育期长度与有效穗数。决定结实率的重要气象因子则是抽穗前15天至抽穗后25天的日照百分率和平均极端最高和最低温度。在建立“库”产量模型时,假定千粒重是稳定的品种特性,空粒率是限制“库”产量的因子而秕粒率的形成则与“源”产量不足有关。模拟值与试验值之间有较好的一致性。     

氮素对马铃薯源-库关系影响研究进展

氮素作为马铃薯必需营养元素之一,对马铃薯产量、品质影响巨大,其中氮素对源-库关系的调控是重要原因。本文系统论述了氮素在基追比、数量和形态等方面对马铃薯源端、库端及其相互关系的影响。同时对有一定研究价值的问题进行思考和展望,以期对马铃薯氮素高效利用和提质增产提供理论参考。     

The impact of variation in grain number and individual grain weight on winter wheat yield in the high yield potential environment of Ireland

Previous studies from regions that produce high proportions of global winter wheat have highlighted that difference in sink size influences the majority of variations in winter wheat yield. However, the potential for source limitation due to environmental differences in regions that consistently produce a large sink capacity (i.e. >20,000 grains/m²), such as Ireland, have not been widely studied. The aim of this study was to characterise the variation in growth pattern and yield components that contribute to variations in grain yield in regions of high yield potential, and to identify the periods of development that are most likely to influence yield in these regions. Monitor crops of winter wheat were grown at three sites with contrasting latitudes on the island of Ireland, during three growing seasons (2013–2015). Crops were assessed regularly for measurements of crop growth and development, including biomass accumulation, canopy development and light interception. Grain yield ranged between 10.7–15.8 t/ha at 15% moisture content, with a grand mean of 12.7 t/ha. Results indicated that variations in grains/m² had a larger effect on winter wheat yield than variations in individual grain weight. Variability in grains/m² was influenced by changes in spikes/m² more than the number of grains/spike. While spikes/m² at harvest was significantly related to the number of shoots/m² at GS59, no significant relationship was observed between the shoots/m² at the time of maximum tillers/plant and spikes/m² at harvest. Furthermore, a significantly negative linear relationship was observed between shoots/m² at the time of maximum tillers/plant and grains/spike. Therefore, high rates of tillering were not beneficial to yield formation in the majority of crops monitored. A strong effect of individual grain weight was observed at one site of the nine evaluated in the study, indicating that a partial source limitation of yield is possible in certain Irish environmental conditions. However, variations in grain yield of crops of winter wheat grown at different locations in Ireland in different seasons were primarily driven by variations in grain number, and therefore were generally sink-limited.     

Pistil abortion is related to ovary mass in olive (Olea europaea L.)

Pistil abortion is considered to be an evolutionary adaptation to save resources in andromonoecious species, balancing the number of pistils with the resources available. It follows that large-fruited species/cultivars should have greater levels of pistil abortion. Working in olive, we found that pistil abortion, expressed as percentage of staminate flowers, was positively correlated to the average ovary mass at bloom, across cultivars with different ovary/fruit mass. Since ovary mass correlated with fruit mass, pistil abortion also correlated with fruit mass. The absolute number of perfect flowers per inflorescence was negatively correlated with both ovary mass and pistil abortion, while the number of staminate flowers per inflorescence increased with both parameters. The total number of flowers (i.e. staminate + perfect) was not correlated to ovary mass or pistil abortion, suggesting that male function was not affected. The results support the hypothesis that pistil abortion is related to competition for resources among ovaries, and suggest that genetic differences in pistil abortion among olive cultivars may be explained by their different pistil mass and sink strength.