农作物高产的适宜土壤水分指标研究

依据大量的实测试验资料，论证了土壤水分对小麦、玉米、棉花生长发育的影响及不同土壤水分与作物产量的关系，分析确定了三种作物高产的适宜土壤水分上、下限指标，为实现高产及节水灌溉提供了依据。     

盘锦地区水稻平衡施肥技术研究

试验采用二次回归"3414"设计,通过田间小区试验研究了盘锦地区典型稻作区氮磷钾配合施用对水稻产量的影响。通过主因素、单因素效应分析,定量地评价了氮肥、磷肥和钾肥用量与水稻产量的关系,提出了目标产量的最优氮磷钾组合方案。从水稻最大经济产量和经济效益综合考虑其最优氮肥(N)用量范围为260～320 kg/hm2,最优磷肥(P2O5)用量范围为150～200 kg/hm2,最佳钾肥(K2O)用量范围为70～100 kg/hm2。     

MSM法优化材积方程的研究

一元材积表是根据胸径(D)与材积(V)的数学模型编制的林业用表。V=aD~b是编制一元材积表最常用的方程。由于上式是非线性的,过去常采用的方法是将该方程转化为线性拟合问题,但这里存在一个问题,非线性方程取对数转化为线性方程后,通过最小二乘法求得的参数对线性方程来说是最优的,而对原非线性方程而言,则误差较大,有进一步优化的必要。本文试图应用改进单纯形法,进一步优化V=aD~b方程的参数a、b,从而提高一元材积表的精度。     

Age trends in the genetic parameters of wood density and the relationship with growth rates in hybrid larch (Larix gmelinii var. japonica × L. kaempferi) F1

Age trends in variance components and heritability of overall wood density, earlywood and latewood density, and latewood proportion were investigated in 29-year-old trees of 19 full-sib families of hybrid larch (Larix gmelinii var. japonica × Larix kaempferi) F₁. The age–age correlation and optimum selection age for these traits were also estimated and genetic and phenotypic correlations between wood density and radial growth rate were calculated for each growth ring. Intraring wood density data were obtained using X-ray densitometry. The coefficient of additive genetic variance was stable over all ages, whereas the coefficient of environmental variances gradually decreased with increasing age, resulting in increases in heritability estimates with age for overall density. The latewood proportion had the highest heritability estimates at all ages, ranging from 0.44 to 0.66. Overall density and its various components at 28 years of age showed strong genetic correlations with their respective traits at all younger ages. Optimum selection ages for the wood density traits ranged from 8 to 14 years, at which point maximum gain efficiencies per year were obtained. There were negative correlations between wood density and radial growth rate at early ages, although these relationships tended to be weaker with increasing age. These results suggest that selection at a young age is effective for wood density, but particular care must be taken in selecting trees with an improved radial growth rate because rapid growth will result in a low-density wood product, especially in the early growth period.     

兰考泡桐和刺槐幼苗最适营养需要的研究

按稳态营养理论和方法,本文研究了兰考泡桐(Paulownia elongata)和刺槐(Robinia pseudoacacia)幼苗的最适营养需要。通过每天测定和调整培养液pH值和电导率,及时补偿消耗的营养物,幼苗体内营养状况和最大生长速率均保持稳定。兰考泡桐幼苗每天生长率高达25％以上,刺槐达15％。营养物利用率90％以上。确定兰考泡桐幼苗最适营养物比例为100N:75K:18P:7Ca:8.5Mg;刺槐为100N:60K:15P:8Ca:9Mg。本文还讨论了最适营养研究在育苗和林地施肥应用的前景。     

基于网络分析法的粮食产后处理模式研究

针对目前粮食产后处理模式存在的问题，利用网络分析法进行了优化分析，并提出了改进措施，经比较分析，改进后的处理模式在处理效率、成本、数量损失、粮食品质以及益本比等方面均有较双改善。     

我国土地资源经济学科体系的建设及其展望

土地资源经济学在我国形成时间虽不长，但该学科发展较快，目前已日趋完善。本文在前人研究的基础上，对我国土地资源经济学科体系建设进行了评述。文中提出了土地资源经济学的概念，评价了土地资源经济学与其它学科之间的关系，探讨了土地资源经济学研究的主要内容和方向，并介绍了我国土地资源经济学的研究重点。     

鲁北地区生态农业优化模式的研究——以山东省邹平县码头乡试区为例

山东省邹平县码头乡生态农业优化模式建设的实践表明，农林水相结合，全面规划，配套实施，建立完善的农田基础设施，充分利用土地资源，是鲁北地区改造中低产田、发展生态农业的有效途径。     

以玉米为基质的灵芝固体发酵条件优化

研究了以玉米为基质的灵芝固体发酵,通过单因素和正交试验对工艺条件进行了优化,在测定菌质多糖含量的同时,测定了菌质中还原糖、蛋白质、游离氨基酸的含量。结果表明:玉米粒度、菌种、接种量、发酵温度和时间对基料中菌质多糖的产生及主要成分含量有显著影响,发酵条件优化结果为10目大小的玉米基料,接入12%液体菌种,28℃发酵20d。经优化后,多糖含量可以达到21.97mg/g,还原糖、蛋白质、游离氨基酸含量也优于其它处理组。     

The Optimum Sowing Time for Plastic-film Corn and the Application of Two Related Theories

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