Behavioral response of Norway rats (<Emphasis Type="Italic">Rattus norvegicus</Emphasis>) to odors of different mammalian species

Behavioral responses to the odors of three predators of rodents (domestic cat (Felis catus), weasel (Mustela sibirica), Eurasian badger (Meles meles)), one non-predator mammal (rabbit (Lepus capensis)), and distilled water (control) were assessed in three types of Norway rats (Rattus norvegicus): wild (WNRs), domestic (DNRs), and albino laboratory Wistar (AWRs). Rats were taken individually to a testing apparatus consisting of a hide box and a testing arena. The behavioral activities, including concealing, heading out, approaching, and feeding behaviors in each trial were videotaped for 3 h. Results revealed that WNRs, DNRs, and AWRs all showed an aversion to the predator odors by spending more time concealing in the hide box: frequencies of approaching and feeding behaviors, as well as the amount of food intake were significantly lower than control group. Our results suggest that the response of DNRs and AWRs were “built-in” or innate in nature as they had never experienced the odors of the tested predators. Moreover, all three types of rats can distinguish between predator and non-predator odors, but the ability of WNRs was the highest, which can distinguish between sympatric and allopatric predators, while the ability of AWRs was the lowest, which spent most time in the hide box. The concealing and approaching behaviors were no significantly different among the five odor exposure groups. Also, the reactions of the three types of rats toward the control group (distilled water) significantly differ. This suggests that the duration of time spent in captivity plays an important role in shaping the response of rats to different predator odors.     

Reducing effect of an extract of Phaseolus vulgaris on food intake in mice — Focus on highly palatable foods

Different lines of experimental evidence indicate that treatment with extracts from and derivatives of Phaseolus vulgaris reduces intake of food, including highly palatable foods and beverages, in rats. The present study was designed to extend to mice these lines of evidence. To this end, CD1 mice were treated acutely with a standardized extract of P. vulgaris and then exposed to unlimited access to regular food pellets (Experiment 1) or 1-hour limited access to three different palatable foods/beverages, such as butter cookies (Experiment 2), a condensed-milk beverage (Experiment 3), and a chocolate-flavored beverage (Experiment 4). Treatment with P. vulgaris extract resulted in a significant reduction in the intake of regular food pellets, that was still evident 24 h later, as well as of the three palatable nourishments. Together, these results (a) extend to mice several previous findings on the capacity of P. vulgaris extracts to suppress food intake in rats, (b) suggest that P. vulgaris extracts may interfere with the central mechanisms regulating appetite, food intake, palatability, and/or the rewarding and hedonic properties of food, and (c) P. vulgaris extracts may represent a potentially effective therapy for overeating, obesity, and food craving.     

乡村旅游饮食文化资源开发研究

乡村饮食文化资源包括各类食物及其加工制品和各种饮食礼俗,它有着丰富的类型,并具有满足基本生理需要、显著自然本色和突出地域特色等特征,在乡村旅游中有着重要的地位和开发价值。在进行乡村旅游饮食文化资源的深度开发时,要加强乡村饮食文化挖掘,保持乡村饮食的“自然本味”,突出乡村饮食的文化包装。     

不同干扰类型下的白桦次生林土壤理化性质研究

研究内蒙古大兴安岭地区不同干扰类型下白桦次生林土壤理化性质特征,在内蒙古根河市选取3种干扰类型的白桦次生林样地的不同土层土壤作为研究对象,对土壤理化性质进行测量分析,探究不同干扰类型对土壤理化性质的影响。研究结果表明,白桦次生林在不同干扰方式下土壤理化性质存在显著差异。其中人工条带改造后的白桦次生林土壤pH值增大,火烧后白桦次生林容重增大,土壤有机碳、全氮、全磷、全钾、速效磷、速效钾含量在人工条带改造后显著增高,采伐干扰样地白桦次生林样地土壤含水量、速效氮含量最高。不同干扰类型的白桦次生林样地土壤理化性质间相关性不同。人工条带改造干扰样地白桦次生林土壤综合指数较高,火干扰样地白桦次生林土壤综合指数较低。     

Studies on food selection behaviour of the Norway rat (Rattus norvegicus) on farms

Measures used to control Norway rats (Rattus norvegicus Berk.) on farms are frequently unsuccessful due to poor bait uptake. In pest-control operations, rats always have the choice between the farms own food resources and the bait. In this study we analysed the individual selection behaviour in two rat colonies when the rats were offered a familiar bait which matched the food on the farm and a bait which was unknown. Bait stations equipped with video and transponder technology were installed in two differently structured areas on a farm. In four experiments, a familiar foodstuff (rolled oats) was put out for 3 days, and then at one of the stations, a test bait was put out for 4 days. The relative palatability of the test baits was known from laboratory experiments. The visits of marked individuals were registered, and the amounts consumed were estimated in the video evaluation. Location preference was determined by offering identical food in two neighbouring bait stations. Social interaction was evaluated using the video recordings. The bait stations were visited on a daily basis irrespective of the supply. Food selection patterns (and bait acceptance) observed in the two differently structured areas on the farm were different. However, the relative palatability among the four test baits was stable and agreed with the ranking in laboratory experiments. Over the days of the experiment there was no significant difference in bait acceptance. Location preference and social interaction influenced the choice of bait station. The results show that it is possible to predict bait palatability in the laboratory, which is an important prerequisite for good bait uptake. However, the bait acceptance level is ultimately determined by the prevailing living conditions in the respective area. For optimising bait uptake, the structure of the areas on the farm must be considered just as much as findings about location preferences and social interaction.     

Invertebrate abundance in different forest habitats as animal food available to capercaillie Tetrao urogallus chicks

Invertebrate abundance was estimated in 1981 and 1982 by sweep‐netting at twelve forest vegetation types in Vegårshei, Southern Norway. Invertebrates are expected to be a major determinant of habitat quality to gallinaceous birds, since animal food is considered essential to young chicks. The twelve fixed stations were chosen to illustrate poor and rich habitats and a gradient from bog to forest habitat. Rich vegetation types also had the highest abundance of invertebrates mainly due to moist and heavy soils. A comparison between a clear‐cutting and a similar vegetation type not logged, showed strong reduction in invertebrate availability after cutting. The influence of this alteration on availability of the capercaillie Tetrao urogallus chicks’ food is discussed.     

Long-term dynamics of a mixed conifer stand in Slovenia managed with a farmer selection system

The single-tree selection system is an important option for management of Norway spruce (Picea abies (L.) Karst.) and silver fir (Abies alba Mill.) forests because it provides continuous cover, requires low investments for tending, and promotes natural regeneration as well as high stand resistance and elasticity. It is often regarded as a very conservative system that usually results in only minor spatiotemporal changes in forest structure and composition. We studied management history, structural changes, regeneration dynamics, and light climate of a traditional single-tree farmer selection silver fir-Norway spruce forest (site typology Bazzanio-Abietetum). Stand structure was analyzed on five 0.25 ha permanent plots in 1994, 2001, and 2008. Regeneration density and height growth, forest floor vegetation, and light climate were also assessed on 1.5 × 1.5 m regeneration subplots in 2001 and 2008. Tree cores extracted from dominant trees from both species in two plots were used for reconstructing stand history and age structure of the canopy layer. We documented the forest response to three types of selection management regimes: excessive, normal, and conservative. Excessive management with harvest intensity significantly above the increment was documented until the late 1950s, including two peaks of heavy fellings (diameter limit cut) in the 1880s and 1930s, which favoured establishment of Norway spruce and released regeneration. The period that followed was characterized by normal selection management, but was nevertheless marked by a decline of silver fir as a result of air pollution and several droughts. This led to sanitary fellings that were carried out from the late 1970s to the early 1990s. In the last two decades conservative management followed, which led to suppression and decline of regeneration, especially of Norway spruce, and loss of selection structure. Although we recorded lower regeneration potential of silver fir compared with Norway spruce within the seedling category, silver fir outcompeted Norway spruce within the small-sized tree category (1 cm < dbh ? 10 cm) because of its superior height growth in low light levels (diffuse light <6%) and occupied a greater share of the canopy. Nevertheless, we anticipate that over the long-term the low light regime will also cause regeneration decline of silver fir and broadleaves. Our research revealed significant structural changes in a single-tree farmer selection forest during the last 150 years. These were a result of variable management regime and environment. A farmer single-tree selection system could better mimic the natural disturbance regime if spatiotemporal combinations of diverse felling regimes would be used.     

Concentrations of Cadmium,Lead and Mercury in Different Soils in Two Swedish Forest Catchments

Accumulation of cadmium (Cd), lead (Pb) and mercury (Hg), as affected by organic matter content, pH of different soil compartments and the physicochemical properties of each metal, was studied in different soil types within two forested catchments of the Norway spruce (Picea abies - Vaccinium myrtillus) type. Independent of soil type, the highest metal concentrations were found in the organic layers of the soil, usually in the surface soil. The concentrations in the upper part of the mineral subsoil were about one-fifth to one-tenth, or less, of those in the organic surface soil. Concentration maxima in the B-horizon were more pronounced for Cd and Hg than for Pb. When comparing soil types, the highest concentrations of Cd were found in the less acidified fens in the discharge area, while for Hg and Pb the highest concentrations usually occurred in the mor layer of the well-drained Podzols. For all metals, the soil types with the largest accumulation had concentrations up to 2-3-fold higher in the organic layers than those with the smallest accumulation.     

Importance of soil extractable phosphorus distribution for mature Norway spruce nutrition and productivity

Phosphorus is an essential nutrient for forest growth. In this study, we assessed the impact of soil extractable phosphorus using two simple extraction methods on nutrition and productivity of Norway spruce in sixteen mature forest stands on different bedrocks and soils in Bavaria, Southern Germany. Representative trees were sampled for needles, twigs, branches, stem bark, and stem wood. Total phosphorus content in the tree parts and soil phosphorus stock extractable with citric acid and sodium bicarbonate up to a soil depth of 80 cm were determined. We found that easily soil extractable phosphorus is a suitable indicator for estimating phosphorus uptake and stand productivity in Norway spruce. In contrast, organic layer phosphorus showed no significant correlation with aboveground biomass phosphorus contents. In the biomass, the highest phosphorus contents were measured in young needles and twigs, but the highest correlation with soil phosphorus was detected for phosphorus contents in needles and bark. The stock of phosphorus extracted by citric acid down to 40 cm soil depth revealed the best correlation with phosphorus in needles and bark. Therefore, as a supplemental or alternative method to needle analysis, our study suggests the use of phosphorus contents in stem bark to evaluate tree phosphorus nutrition. These results highlight the suitability of the citric acid soil extraction method to characterize plant available phosphorus in Norway spruce ecosystems.     

山西野生沙棘结实性状和果实营养成分研究

了解沙棘种质资源特性是其种质创新和良种选育的基础。为给沙棘资源的开发利用和良种培育提供理论依据,分别从山西省沙棘野生资源重要分布区的右玉、交城、古交和沁源共采集了45个沙棘单株的果实样品进行观测与分析,比较分析了不同单株、不同采样地区、不同颜色果实的结实性状(结实密度、果实横径、果实纵径、果形指数、果柄长度和百果质量)和营养成分(可溶性固形物、可溶性糖、可滴定酸、VC和黄酮含量)及其差别,并对其性状特性与营养成分间的相关性进行了分析。观测结果表明:采集于交城的27号单株在结实特状和果实外观品质上的表现均最优,果实中的可溶性固形物、可滴定酸、VC、黄酮含量均最高的单株编号分别为10、7、32和27号;不同地区沙棘的结实密度、果柄长度和果实中VC、可溶性固形物含量间均存在显著性差异,其中采集于古交的沙棘果实其结实密度最大,采集于沁源的沙棘果实其VC含量最高,采集于古交的沙棘果实其可溶性固形物含量最高;不同颜色沙棘果实间其百果质量、结实密度、果实横径和纵径均存在显著性差异,黄色果的百果质量最大但结实密度最小。相关性分析结果表明:果实中的黄酮含量与VC含量间呈极显著正相关,而与可溶性糖含量间呈显著负相关。     

Modelling dominant height growth from national forest inventory individual tree data with short time series and large age errors

We developed dominant height growth models for Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) in Norway using national forest inventory (NFI) data. The data were collected for a different purpose which potentially causes problems for dominant height growth modelling due to short time series and large age errors. We used the generalized algebraic difference approach and fitted 15 different models using nested regression techniques. Despite the potential problems of NFI data the models fitted to these data were unbiased for most of the age and site index range covered by the NFI data when tested against independent data from long-term experiments (LTE). Biased predictions for young stands and better site indices that are better represented in the LTE data, led us to fit models to a combined data set for unbiased predictions across the total data range. The models fitted to the combined data that were unbiased with little residual variation when tested against an independent data set based on stem analysis of 73 sample trees from southeastern Norway. No indications of regional differences in dominant height growth across Norway were detected. We tested whether the better growing conditions during the short time series (22 years) of the NFI data had affected our dominant height growth models relative to long-term growing conditions, but found only minor bias. The combination with LTE data that have been collected during a longer period (91 years) reduced this potential bias. The dominant height growth models presented here can be used as potential height growth models in individual tree-based forest growth models or as site index models.     

经济林新资源食品的种类及前景

开发利用经济林新资源食品是林业产业发展的一项重要内容。本文重点介绍了我省现有的经济林新资源食品的种类、栽植面积、分布区域、发展现状及开发潜力,对于未来我省经济林新资源食品的开发、利用具有积极意义。     

不同穗条类型、长度的欧洲云杉扦插苗质量评价

[目的]为欧洲云杉扦插穗条选择和扦插苗培育提供依据。[方法]采用完全随机区组试验设计,研究了2种穗条类型(嫩枝基部带1.5年生硬枝、嫩枝)、3种穗条长度(5 10、10 15、15 20 cm)的嫩枝扦插苗从移植当年到第3年的成活率、保存率和生长情况。[结果]2种穗条类型扦插苗间的移植成活率和保存率差异不显著,但移植后嫩枝基部带1.5年生硬枝扦插苗的苗高、新梢生长量、地径、侧枝数、冠幅、鲜质量、干质量差异显著,都是嫩枝基部带1.5年生硬枝扦插苗大于嫩枝扦插苗。3种长度扦插苗的移植成活率、保存率的差异均显著;其中,15 20 cm长度穗条扦插苗移植成活率和保存率最高,分别是98.00%和86.00%,不同长度穗条扦插苗移植成苗率逐年下降,而且与穗条长度有关,弱小穗条获得的扦插苗成苗率低;5 10 cm的扦插苗移植成活率为46.00%,到第3年时保存率仅为23.33%,且移植后苗高、新梢生长量、地径、侧枝数、冠幅、鲜质量、干质量的差异也显著,且都以15 20cm穗条的扦插苗值最高,10 15 cm穗条的扦插苗次之,5 10 cm的扦插苗最小。嫩枝带硬枝扦插苗的苗木质量指数(QI)是嫩枝的7.74倍,15 20 cm穗条的扦插苗质量指数(QI)是5 10、10 15 cm扦插苗的5.47、5.23倍。扦插苗地径初始值与移植当年地径、苗高初始值与移植当年苗高间呈极显著正相关关系。[结论]扦插苗最初的生根状况和穗条质量影响后期培育过程中的存活和生长,嫩枝基部带1.5年生硬枝扦插苗和15 20 cm穗条的扦插苗不仅移植成活率、保存率高,而且生长量、生物量、质量指数都比短而弱小穗条的扦插苗高。     

不同变异类型杜仲叶片含胶性状的变异规律

为了弄清不同变异类型杜仲叶片含胶特性的变异规律,同时为了给杜仲胶优良资源的选择和有效利用提供理论依据,采用选择典型样株和随机取样的方法和含胶率的测定采用杜仲胶综合提取法进行了研究.结果表明:不同变异类型杜仲叶片的形态特征和含胶性状表现出不同的特点,其中4个变异类型叶长存在显著差异,而叶宽、叶形指数、叶面积、单叶质量、叶片含胶率和单叶含胶量的差异都达到极显著水平;叶片含胶率和单叶含胶量都是浅纵裂型最高,深纵裂型最低.     

不同光质对美国红栌叶色表达的影响

以美国红栌为研究材料,使用4种不同颜色的转光膜对其进行35 d的遮光处理,然后测定其叶片内色素含量与营养物质组成。结果表明,不同光质处理会影响叶片的色素含量：1）红光和绿光处理下,叶绿素与类胡萝卜素含量显著高于对照,花色素苷的含量显著低于对照。2）蓝光处理下,叶绿素b含量显著低于对照,花色素苷含量高于其他3种光质处理的。3）黄光处理下叶片的叶绿素、类胡萝卜素及花色素苷含量均低于其他处理。4）叶片中氮在红光处理下含量最高,在黄光处理下含量最低;磷在蓝光、红光和绿光处理下含量均高于自然光处理,在黄光处理下含量最低;钾含量在蓝光处理下最高。5）除绿光外,其他3种光质处理下的可溶性糖含量均显著高于自然光处理。     

Zur Überwachung des grünen Eichenwicklers,Tortrix viridana L. (Lep., Tortricidae) mittels synthetischen Sexualpheromons

In the period from 1986 to 1988 the synthetic sexual pheromone ofTortrix viridana L. and different types of traps were investigated in Slovakian oak forests. The dependence of male numbers per trap on the forest type groups was studied parallely as well as the attraction of pheromones for other moth species was tested, too. The pheromon TV83 (Z11-14: Ac+Z11-14: OH, 9∶1, 50 μg) and unsticky plastic trap with DDVP called “Mushroom” showed the highest effectivity. The pheromon monitoring confirmed the theory that the pest prefers the biotops with dominance ofQuercus pubescens andQ. robur. The optimum of pest was bound to forest type groups Carpineto-Quercetum und Ulmeto-Fraxinetum carpineum. The minimal number of other moth species was observed in traps with pheromons TV83 (?SFR) and Hoechst (FRG).     

Activity ofBacillus thuringiensis isolates on the corn borers,chilo agamemnon Bles. (Crambidae) andOstrinia nubilalis Hbn. (pyraustidae)

The potential activity of different varieties ofBacillus thuringiensis was evaluated against the second instar larvae of the two lepidopterous corn borersChilo agamemnon andOstrinia nubilalis. Data on the LC₅₀, slopes, 95% confidence limits and potencies of the tested varieties were determined. WithO. nubilalis, Dipel 2X (Bacillus thuringiensis. var.kurstaki HD-1) was the most potent and the LC₅₀ was 2.68 μg/g diet. The LC₅₀ for other varieties ranged between 3.12 and 31.95 μg/g. In the case ofC. agamemnon, the lowest LC₅₀ was also determined with Dipel 2X being 3.68 μg/g diet; this ranged between 6.2–15.11 μg/g for other tested varieties.     

Monolignol oxidation by xylem peroxidase isoforms of Norway spruce (Picea abies) and silver birch (Betula pendula)

We partially purified peroxidase isoform fractions from xylem extracts of a gymnosperm, Norway spruce (Picea abies (L.) Karst.), and an angiosperm, silver birch (Betula pendula Roth.), to determine the participation of xylem-localized peroxidases in polymerization of different types of lignin in vivo. Several peroxidase fractions varying in isoelectric point values from acidic to basic were tested for their ability to catalyze the oxidation of the monolignols coniferyl alcohol, sinapyl alcohol and p-coumaryl alcohol in vitro. All of the xylem peroxidases extracted from Norway spruce and most of those from silver birch showed the highest rate of oxidation with coniferyl alcohol in the presence of hydrogen peroxide. The exception was an acidic peroxidase fraction (pI 3.60-3.65) from silver birch that exhibited higher oxidation activity for sinapyl alcohol than for coniferyl alcohol. For the xylem enzyme fractions extracted from silver birch, the ability to oxidize the artificial phenolic substrate syringaldazine coincided with high specific activity for sinapyl alcohol. Therefore, we conclude that the acidic, neutral and basic xylem peroxidases of Norway spruce all function in the synthesis of guaiacyl-type lignin, whereas in silver birch the acidic peroxidases preferentially oxidize sinapyl subunits. The latter provides a mechanism for synthesis of guaiacyl-syringyl lignin typical of tracheid cell walls in angiosperm trees.     

Susceptibility of four conifer species to Gremmeniella abietina

G. abietina causes severe dieback in pole-stage stands of Scots pine in Britain. The susceptibility of ll provenances of Scots pine and of three other conifer species was tested by inoculations. Significant differences in susceptibility were found amongst Scots pine provenances, with those originating from a native Scottish pinewood at Loch Maree showing the highest levels of disease. Corsican pine was shown to be the most susceptible species tested although sporulation was greatest on Scots pine. Norway spruce was also shown to be susceptible when inoculated late in the growing season. Infection in lodgepole pine was negligible. High levels of β-phellandrene were tentatively linked with resistance among trees in a single stand of Scots pine.