不同波长诱虫灯对蜀柏毒蛾成虫的诱集研究

采用波长分别为300 nm、340 nm、380 nm、420 nm、460 nm、500 nm、540 nm和580 nm、功率8W的诱虫灯进行了蜀柏毒蛾成虫的诱集研究.结果表明：8种波长的诱虫灯诱集效果有差异,波长340nm、功率8W的诱集效果最好.波长340 nm、功率8W诱虫灯在60 min时间内对距离在180 m范围内的蜀柏毒蛾成虫具有诱集效果,但诱集率达87.1％以上的距离在120 m以内.     

近红外光谱数据建模方法的研究进展

应用化学计量学对近红外光谱数据进行建模是近红外光谱分析中的难点和关键。随着研究的深入,现有分析建模的改进算法和新方法的应用不断出现。本文详细阐述了数据预处理、定性和定量建模优化方法的研究进展。在降噪消噪方法中,小波(WT)变换是最为常用和有效的工具,应用非常广泛。波长优化选择方法是现在研究的重点之一,主要有遗传算法(GA)、无信息变量消除方法(UVE)和连续投影算法(SPA)等。在模型优化算法中,主要是在偏最小二乘法(PLS)、人工神经网络(ANN)和支持向量机(SVM)的基础上提出多种改进算法,能够更加有效地优化模型。但每种算法各具优点的同时也存在着一定的局限性,对于不同类型待测物的数学模型,优化的方法也有所不同,所以在实际应用中将多种数学挖掘方法结合,相互取长补短,将成为今后研究趋势。      

福寿螺对不同颜色光的趋避效应初探

采用不同颜色(即不同波长)的光对福寿螺(Ampullaria gigas)进行室内照射试验,分析探讨了不同壳色福寿螺的趋避效应。结果发现,黄壳螺较黑壳螺对光更为敏感,橙色和红色光对黄螺有明显的驱避效应,黄螺对黄色光趋向性最高;红色光对黑螺有明显的驱避效应,黑螺对绿光和蓝光的趋向效应更为明显。研究结果可为利用灯光对稻田福寿螺进行物理防控提供一定的科学依据。     

Spectral dependence of photosynthesis and light absorptance in single leaves and canopy in rose

Little is known about the effects of leaf pigmentation (related to leaf ontogeny), on the spectral dependence of photosynthesis and most observations have been limited so far to single leaves. This study aimed to investigate photosynthesis and the related optical properties of two types of rose leaves, young reddish leaves and middle age green leaves, and to quantify the spectral dependence of photosynthesis at the canopy level.     

蚜虫对不同色卡敏感性及对不同波长黄色粘虫板趋性

采用蓝、绿、黄、红、黑、白、银灰7种颜色对蚜虫进行系统的颜色趋性研究,发现其对黄色趋性较强,对银灰色有拒避性。通过黄色最佳诱蚜波谱分析,表明其对波长为575.0 nm的黄色卡趋性最强,且通过对粘虫板一天中的诱蚜规律分析,发现8:00-10:00、16:00-18:00对蚜虫的诱捕量较多。     

Lighting the way: Towards reducing misorientation of olive ridley hatchlings due to artificial lighting at Rushikulya, India

Sea-finding behavior in sea turtle hatchlings is modified by the visual cues provided by artificial beach front lighting. The consequent landward movement of hatchlings in response to coastal electric lighting reduces their survival rates. We assessed the potential impact of coastal lighting at Rushikulya, an important mass nesting site of the olive ridley sea turtle (Lepidochelys olivacea) in the Indian Ocean region. We examined the response of hatchlings to light characteristics in an experimental setup, as well as to the existing lighting regimes along the beach, using arena trials. Previous studies on other species indicate preferential orientation towards low wavelength and high intensity light. Our study confirms these preferences among hatchlings from the Indian Ocean population of olive ridleys. In addition we also found that wavelength and intensity could have an interactive effect upon hatchling orientation. Hatchlings at the study site respond both to visible point sources of light and to sheer glows of light. Though beach plantations of introduced Casuarina equisetifolia are generally considered to have negative impacts on sea turtle nesting beaches, we found that they acted as an effective light barrier when planted about 50 m away from the high tide line. We developed a model of the expected impact of artificial lighting on hatchling orientation during mass hatching events of previous years, and predict as much as 50% misorientation in some years. We also developed a map representing the misorientation of hatchlings due to artificial lighting based on arena trials in different regions of the beach. The results of the study helped identify focal areas for light management on the beach, which could be critical for the survival of this population.     

Hyperspectral reflectance data processing through cluster and principal component analysis for estimating irrigation and yield related indicators

Management of agricultural practices such as irrigation by using remotely sensed data requires background data obtained from field experiments carried out under controlled conditions. In this study, spectral and agronomic data from field trials consisting of six different irrigation treatments were used to derive new spectral indicators for estimating growth level and water use status of dwarf green beans. Spectral reflectance (Ref) values were smoothed and first-order derivative spectra (ρ) were calculated. Linear regression and multivariate analysis (cluster and principal component analysis) were done between agronomic indicators and both the smoothed spectral reflectance (R) and ρ of each individual wavelength between 650 and 1100 nm. Based on those calculations, the most appropriate wavelengths were selected for each agronomic indicator and new combinations were calculated by using rationing, differencing, normalized differencing and multiple regression. The ratio between ρ measured at 950 or 960 nm and 1020 nm wavelengths provided estimates in an error band of 2.47 bar for Leaf Water Potential (LWP) and 3.18% for Leaf Water Content (LWC). An equation based on ρ740 and ρ980 was developed to estimate Leaf Relative Water Content (LRWC). In the same manner, the ρ at 820 and 970 nm provided a good estimate of crop water use and the ρ values at 770 and 960 nm were critical for the calculation of Leaf Area Index (LAI) and dry biomass. It was also determined that the ratio of R930 to R670 can be applied to yield estimation.     

LED养蜂照明光源研究

[目的]为养蜂场所设计一种红色照明灯,用于夜间、暗室内取蜜或观察管理蜂群。[方法]分析蜜蜂与人视觉器官的视觉生物学特性,采用发光波长在650～780 nm的高亮度红光LED来作为光源,并举例红光LED头灯的设计,对头灯光源的波长和亮度进行了详细分析。[结果]LED光源的适宜照度为3～10 cd/m2。基于蜜蜂对红色光呈现色盲的生物学特性,以红光LED为光源的LED灯,作为养蜂场的照明灯具,使蜂群不受或少受惊扰,有效减少蜂群的飞遗损失。[结论]结合现代电子技术,顺应蜂群的生理特征,研发出合理先进的蜂具。     

Influence of sprayable mulch colour on yield of eggplant (Solanum melongena L. cv. Millionaire)

Planting beds were treated with sprayable, synthetic latex film (BASF, Charlotte, NC, USA) and oversprayed with black, white, red, blue, yellow or silver oil-based paint to study the effect of coloured spray mulches on yield of eggplant (Solanum melongena L. cv. Millionaire). Nonpainted mulch base and bare ground plots served as control treatments. Individual experimental units consisted of three rows, 102 cm wide × 7.3 m long, transplanted with 8 plants per row. Treatments were replicated in four blocks each at two separate locations near Fresno, CA. Plants grown on silver-painted beds produced significantly greater numbers (42–221%) of fruit and total fruit weight (42–237%) than all other treatments at both locations after eight harvests. Silver-painted mulch stimulated significantly greater flowering and fruit set numbers prior to the first harvest at one site. Apart from silver, only blue- and white-coloured mulches provided increased numbers and/or fresh weight yields at one site only. Mulched plots painted with other colours did not produce yields different from either the bare ground or nonpainted mulch base controls at either site.     

基于随机森林的鱼粉蛋白近红外定量分析

基于近红外(NIR)光谱技术,采用随机森林(RF)回归方法测定饲料鱼粉的蛋白含量。考虑到RF模型的随机性,通过调试决策树数量(ntree)和分裂变量数目(nsv)来进行模型优选;利用基尼系数(G)的下降量来判断近红外波长变量的建模重要性,进而为鱼粉蛋白的NIR分析优选信息波长,以提高NIR定量分析精度。根据统计学原理,选择具有较低计算复杂度的等效最优模型。优选的RF模型构建471个决策树,需要随机的103个波长变量进行树节点分裂,同时通过计算节点分裂前后G的平均下降量来选择52个近红外信息波长进行定标校正,得到等效最优的校正模型,校正均方根偏差和校正相关系数分别为3.970%和0.943;经过独立的预测集样品对最优RF模型进行检验,预测均方根偏差为5.271%,预测相关系数为0.906,说明RF回归结合G系数的波长优选能够有效地提高NIR光谱应用于鱼粉蛋白定量的预测能力。