果园免耕的生态特性及功能

发展观光性有机生态果园,生产优质果品的最基本条件为恢复沃土,减少对土壤的污染和伤害.果园土壤管理最好的方法是免耕生草法.通过研究果园免耕生草所形成的植物群落的生态特征及功能,进一步发展果园免耕技术,探讨形成有机观光果园优美宜人的生态小环境的可行性方法.     

旋轨耦合作用下BH分子激发态的特性研究

采用旋轨耦合作用下多组态准简并微扰理论(SO-MCQDPT)研究了BH分子的基态X1+和第一激发态3的性质,得到了第一激发态3的分裂电子态30、31和32的势能曲线;采用Murrell-Sorbie函数和最小法二乘法拟合得到了这3个分裂电子态的解析势能函数,并在此基础上推导出了基态X1+和分裂电子态30、31和32的光谱常数,而且得到了分裂态的垂直跃迁能ν[31(ν=0)→30(ν=0)]=2531.116 cm-1和ν[32(ν=0)→31(ν=0)]=0.005 cm-1,这些分裂电子态的解析势能函数和光谱数据均为首次给出。     

共管机制下草地资源管理的行为主体分析

以草地共管项目示范区云南省x县H村为例，把参与共管的3个行为主体（社区村民、当地政府、非政府组织）作为主要研究对象，理性分析他们之间的利益互动关系，探讨共管各个环节各行为主体的角色定位与职能作用。针对其中2个自然社的共管效果绩效评估差异及其形成因素进行了横向对比分析，以探索制约草地共管效果的深层问题和关键因素。     

农业基建项目的甲方管理职能探讨

分析了农业基本建设项目在设计阶段、招标阶段、施工阶段中甲方的管理职能，相应地提出了甲方管理工作的重点。     

Long‐Term Impacts of Post‐Fire Mulching on Ground‐Dwelling Arthropod Communities in a Eucalypt Plantation

In the past decades, Portugal like several other Mediterranean countries has been affected by frequent wildfires. This has led to various field tests of post‐fire soil conservation measures and, in particular, mulching with forest slash residues. While forest residue mulching was shown to be highly effective in reducing post‐fire erosion, its side effects on soil fauna communities have not been studied and are also difficult to predict from the – scarce – literature on mulch effects in general. Therefore, this study compared the abundance, diversity and taxonomic and functional composition of the ground‐dwelling arthropod communities of three mulched and, as control, three untreated erosion plots of roughly 100 m² that had been installed in a eucalypt plantation almost immediately after a wildfire in 2010, some five years earlier. This was done using three pitfall traps per plot, placed at the lower, middle and upper part of the study slope. Roughly five years after mulching, its impacts on the ground‐dwelling arthropod were rather limited, especially compared to its effect on overall soil erosion rates. One of the few exceptions was the abundance of the Hymenoptera – one of the most frequently occurring orders – which was significantly lower in the mulched than control plots. This and other near significant mulching impacts found in this study plainly justify a follow‐up study on short‐term effects. Copyright © 2016 John Wiley & Sons, Ltd.     

有机铬的营养与生理作用研究进展

铬是人和动物必需的微量元素之一,在机体许多生理机能中起着重要作用.本文主要对最近国内外有关有机铬对动物物质代谢、生殖和内分泌功能、免疫功能和抗热应激的影响及有机铬的添加效果和毒性等几个方面的相关研究进行综述,旨在为研究有机铬的营养作用提供参考.     

土壤传递函数在计算土壤饱和导水率中的应用

以河南省封丘县为研究区域,应用7种土壤传递函数(Campbell、Cosby、Brakensiek、Wosten1997/1999、Saxton和Li的方法)分别对该地区不同深度土壤的饱和导水率值进行了模拟预测。通过与野外采样数据的统计分析比较,获得了适用于该地区各层次土壤饱和导水率的传递函数方程,分别选用Wosten1999和Li的方法建立了分层土壤饱和导水率分布图,为该地区的土壤水分运动模拟提供了基本土壤水文资料。     

Walsh Sequences Generation with Rademacher Functions and Its Digital Realization

This paper first discusses the application of Walsh sequences in the forward link and the reverse link of the IS-95 system. The advantages and disadvantages of each way generating Walsh sequences are analyzed. The theory and step of using Rademacher function to construct Walsh sequences is discussed especially. Then a way of generating Walsh sequences with CPLD is presented and the Design is described by VHDL on CPLD chip. This way mostly relays on digital logic operation, so it can be realized easily through digital circuit and it needs little memory unit. The result of emluator makes clear this way is feasible.     

水稻上三种条斑病细菌DNA的多态性初析

 试用40个引物对我国水稻条斑病菌、"稻短条斑病菌"和李氏禾条斑病菌等14个代表菌株进行RAPD分析,其中11个引物的扩增产物表现明显的多态性,共扩增出158条谱带,多态性为89.74%。聚类分析结果显示14个菌株可区分为3个类群,第1群包括LLS2、LLS3、LLS4、RS05、R1008、TAS和TAX;来自不同稻区水稻条斑病菌的群体结构差异明显,分属于第2群(如RS-Hai等)和第3群(如RS105等)。菌株DNA-RAPD指纹分析和致病性测定结果证明:李氏禾条斑病菌、"稻短条斑病菌"在水稻和李氏禾上不仅可相互侵染,而且遗传背景的相似性较高,确认是同一种病菌,其与小麦黑颖病菌亲缘关系较近,但与水稻细菌性条斑病菌具有明显差异。     

模糊限制语的语用功能及其在跨文化交际中的作用

模糊限制语(hedges)是自然语言的一种属性,它的作用是限制模糊词的模糊程度.模糊限制语的这一语用功能,在跨文化交际中既有积极作用又有消极作用,我们要发挥其积极作用,克服其消极作用,从而使跨文化交际得以顺利进行.