用NOAA图像监测冬小麦面积的方法研究

冬小麦种植面积是农情监测中一个重要的监测因素,对生产管理与产量预测有重要意义。该文在冬小麦与同期主要大宗作物绿度－时相曲线对比分析的基础之上,建立反映冬小麦种植区域的差值植被指数图像,采用遥感－统计的方法,对利用ＮＯＡＡ图像进行冬小麦种植面积遥感监测进行了初步研究。通过对我国冬小麦主产区的河北、河南和山东三省的监测实验证明,该方法适用于大范围的冬小麦种植面积遥感监测。     

太阳能与发电余热复合沼气增温系统设计

为了实现大中型沼气工程在北方寒冷地区的应用推广。该文针对北方寒冷气候特点,以哈尔滨双城市沼气工程为例构建了1套太阳能-发电余热中温厌氧发酵增温系统,阐述了该增温系统的设计原理,并对沼气发酵热负荷、发电机组余热回收利用率、太阳能集热装置热效率等关键参数进行了理论计算。计算得出该沼气工程全年平均每日热量的损失为6659.2 MJ,太阳能-发电余热中温厌氧发酵增温系统全年平均每日集热量为7017.6 MJ。通过对增温效果与该工程的热量损失进行对比,表明12、1、2月份系统需沼气发电机组额外提供372.2、369.4、208.3 kWh电量增温,其余月份系统可以实现发酵工程每日热量损失的补充,保证该工程的稳定运行。在8月份对示范工程的一次发酵罐体进行了增温效果测试,表明该增温系统在28 d左右可将该发酵罐内物料温度提升到中温发酵水平。该文为北方寒冷地区大中型沼气增温保温设备的配套建设提供参考。     

A comparative analysis of element composition of roots and leaves of barley seedlings grown in the presence of toxic cadmium,molybdenum, nickel,and zinc concentrations 1

Barley seedlings were grown in hydroponic culture in the presence of toxic concentrations of cadmium (Cd), molybdenum (Mo), nickel (Ni), and zinc (Zn) and analyzed for element composition [boron (B), calcium (Ca), Cd, iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), phosphorus (P), and Zn]. In a first survey, heavy metal concentrations were selected which resulted in a similar inhibition of root growth. Toxic concentrations of Cd, Mo, Ni, and Zn revealed both similar and distinct effects on specific leaf and root element contents. Examples for such responses were decreasing contents in root Mn and Mg at elevated levels of all heavy metals, including Mo, in the medium. In contrast, changes in root contents of B were specific for the applied type of heavy metal stress. The heavy metal dependent changes in B, Ca, Mg, and Mn contents were studied in more detail. In some cases, severe heavy metal toxicity caused excessive accumulation or depletion of nutrient elements that may be deleterious to the plants in addition to other primary damages caused by the heavy metal ions.     

论无效行政行为的救济

如何对无效行政行为进行救济,是理论界尤其是实践界颇为棘手的一个问题。笔者在论证私力救济必要性的基础上,提出以私力救济(相对方行使抵抗权)和公力救济(相对方提起确认无效之诉)相结合来对无效行政行为进行救济的初步设想。     

荔蝽中乙酰胆碱酯酶活性与自然抗药性的关系

本文研究了荔蝽头部乙酰胆碱酯酶(AChE)活性的季节性变化与自然抗药性的关系,以及敌百虫对AChE的影响,同时运用聚丙烯酰胺凝胶电泳的方法,探讨了荔蝽酯酶同功酶的变动情况。结果表明:荔蝽正常成虫头部AChE活性在新羽化成虫中最高,比活力达3.5μmol min~(-1)mg~(-1)蛋白质,越冬期最低,仅1.17μmol min~(-1)mg~(-1)蛋白质,到生殖期又上升为2.67μmol min~(-1)mg~(-1)蛋白质。经敌百虫处理后,在新羽化成虫期和生殖期AChE活性有明显被抑制现象,其比活力分别为2.21μmol min~(-1)mg~(-1)蛋白质和2.04μmol min~(-1)mg~(-1)蛋白质,而在越冬期AChE活性几乎不受敌百虫影响,为1.24μmol min~(-1)mg~(-1)蛋白质,同功酶谱也显示AChE在不同季节中无明显变化。     

2012年四川省稻飞虱大发生特点及原因分析

2012年四川省稻飞虱大发生,具有迁入时间特别早、迁入峰次多、灯下田间虫量大、发生面积大等特点。造成大发生的原因主要是境外虫源基数大,根据工作经验判断作为四川省虫源地的广西虫量大以及四川省今年的气候条件有利于稻飞虱的迁飞、繁殖。     

Laboratory and on‐farm evaluation of low‐cost salt mixtures for use during salinity acclimation and the nursery phase of Pacific white shrimp (Litopenaeus vannamei)

The current study evaluates the efficacy of a low‐cost salt mixture (LCSM) to replace expensive reconstituted sea salt (RSS) in the salinity acclimation and nursery phase of Pacific white shrimp under laboratory and farm conditions. LCSM was formulated to yield sodium, potassium, calcium and magnesium concentrations closely comparable to that of diluted seawater. Laboratory‐based nursery trials were conducted at 2, 6 and 15 g/L salinities, incrementally replacing RSS with LCSM (25%, 50%, 75% and 100%) at four replicates per treatment. Thirty postlarvae were reared for 7 days in 24‐L aquaria during the 2 and 6 g/L trials, while the nursery trial for 15 g/L salinity was conducted for 21 days with 400 postlarvae stocked in 150‐L tanks. On‐farm evaluation of LCSM was carried out in two tank‐based systems installed on levees adjacent to shrimp production ponds. RSS was incrementally replaced with LCSM (0%, 50%, 75% and 100%) and 100 postlarvae stocked into each 800‐L tank. Salinity acclimation was done from 30 g/L to 6 or 1.5 g/L within 2–3 days by pumping water from adjacent shrimp production ponds. Following salinity acclimation, the S4 system maintained flow‐through at 1.5 g/L, while N10 system was maintained static at 6 g/L salinity. At the conclusion, no significant differences were observed for either survival or growth of shrimp postlarvae between RSS and LCSM treatments at all salinities examined. Results reflect the potential use of LCSM to replace RSS, which could be an excellent solution to bring down the cost of production in inland shrimp aquaculture.     

基于RIL群体鉴定棉花抗黄萎病相关QTLs

【目的】鉴定出能够稳定表达的棉花抗黄萎病相关数量性状位点(Quantitative trait loci,QTLs)。【方法】以抗落叶型黄萎病棉花品种常抗棉和感黄萎病品种TM-1为亲本配制的111个重组自交系家系为作图群体,筛选出多态性简单序列重复(Simple sequence repeat,SSR)标记,并用于构建遗传图谱。用完备复合区间作图法对该群体在安阳大田、新疆重病地及病圃等多个环境下的黄萎病病情指数进行QTLs检测。【结果】构建了1张含有12个连锁群、40个标记、总长212.5 cM(厘摩)的遗传图谱。获得了6个与抗黄萎病基因相关的QTLs,对数优势比(Logarithm of the odd score,LOD)分布在2.51～5.55,贡献率最大为20.34%,最小为6.93%。其中,qVR-D05-1能够在安阳大田2015年7月15日和新疆南疆重病地2016年7月9日2个环境中检测到,贡献率分别为12.96%和20.34%。【结论】本研究得到的qVR-D05-1能够为定位出稳定的棉花抗黄萎病相关QTLs提供参考。     

厦门市行道绿化树种凤凰木的调查研究

本文研究了厦门市行道绿化树凤凰木的生长状况，并拟合了树高（H）与年龄（Y）的最优模型，H＝（－35．652＋9．003Y）／Y，胸径D1，3）与年龄（Y）的最优模型：D1，3＝（－316．647＋48．462Y）／Y。结果表明，凤凰木行道绿化树在夏季具有降温增湿的小气候效应，凤凰木对台风的抗逆性强而且抗病虫害。