The Status and Management of Bear Resources in China

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Behavior of Brown Bears (Ursus arctos) in Captivity during Mating Season

IntroductionBrownbearisanen~redspecies.ThereisverylowwiahonOfbroWnbearsinthefie1d.Theanificialbredngincaghvitybecon1esaveryimPOrtantaPProachtoiareasethenumberofbearsandtorecoverwildbearresources.ThempseofthisstUdyistoProvidebasicbouSeAninfOnnationfOrthesu…     

Behavior of brown bears (Ursus arctos) in captivity during mating season

From 1991 to 1992, we observed behavior of 7 brown bears (5 females, 2 males) in mating season. Results showed that the oestrus of brown bears was mainly from May to July. The oestrus of most individuals occurred at the end of May and the beginning of June. There were some differences in the oestrus among individuals. Average duration of the oestrus was 30.8 days (16–50 days). The mating behavior was mainly observed during 8.00–9.00 a.m., and 15.00–16.00 p.m., Rest and sleep were the next behavior after mating for most bears, especially for male bears. All bears had poor appetite. The pattern and process of a successful mating was that a male bear approached a female, smelled the pudendum of the female, climbed on female hip, mated, parted and rested. Oestrus females approached males sometimes. (Responsible Editor: Sun Yueqi)     

Grizzly bears and forestry: I: Road vegetation and placement as an attractant to grizzly bears

Today's growing demand for timber is increasing road development in once roadless forest ecosystems. Roads create both local changes in plant communities and landscape-level changes in forest connectivity. Roads also increase human access, which can be detrimental to species such as grizzly bears. Because most grizzly bear mortalities occur near roads, we examined grizzly bear attractants near roads, which could increase bear use of roadsides and consequently increase human/grizzly bear interactions. We measured the prevalence of 16 grizzly bear foods near roads and examined patterns in road placement to better understand use of roaded habitats by grizzly bears in west-central Alberta. We found that roadsides had a higher frequency of ants, Equisetum spp., Taraxicum officinale, Trifolium spp., graminoids, and sedges; whereas, interior forest stands had a higher frequency of Shepherdia canadensis, Vaccinium myrtilloides, V. vitis-idaea, and ungulate pellets, an indicator of ungulate presence. In addition, roads near water had a greater occurrence of Arctostaphylos uva-ursi and Equisetum spp. than roads not near water, indicating that road placement influenced bear food diversity. Patterns in road placement varied between the upper and lower foothills, although models for the lower foothills predicted road placement in both regions. In the lower foothills, roads were constructed at low elevation, low soil moisture, high sun exposure, and intermediate terrain ruggedness, possibly similar to sites selected by bears. Reducing grizzly bear foods near roads should involve decreasing the width of roadside ditches, banning the planting of clover (Trifolium spp.), and reevaluating road placement in areas with high grizzly bear density.     

河南铁线莲属植物分类学研究(英文)

铁线莲属(Clematis L.)是一个在分类上较困难的类群,种类多,形态变化大。全球铁线莲属植物有350余种,中国有150余种。2006年7~8月我们对河南四大山区的铁线莲属植物种类进行了调查、采集和鉴定,标本存放于河南农业大学标本馆(HEAC),此外我们还认真观察了中国科学院植物研究所标本馆(PE)等国内各大标本馆的铁线莲属植物标本。结果表明河南铁线莲属植物24种和11变种,按照王文采等的铁线莲属新分类系统分别隶属于4亚属、7组、11亚组、15系,其中首次报道了半钟铁线莲(C.sibiricavar.ochotensis)和长冬草(C.hexapetalavar.tchefouensis)为河南铁线莲属植物新记录,首次报道了Clematis honanensisS.Y.WangC.L.Chang’作为Clematis pseudootophoraM.Y.Fang in W.T.Wang的新异名。增补《河南植物志》(1981)中未记录的有5种5变种:女萎(C.apiifoliaDC.)、毛萼铁线莲(C.hancockianaMaxim.)、大花威灵仙(C.courtoisiiHand.-Mazz.)、芹叶铁线莲(C.aethusifoliaTurcz.)、巴山铁线莲(Clematis pashanensis(M.C.Chang)W.T.Wang)、扬子铁线莲(C.puberulaHook.f.et Thoms.var.ganpiniana(Levl.et Vant.)W.T.Wang)、狭裂太行铁线莲(C.kirilowiiMaxim.var.chanetii(Levl.)Hand.-Mazz.)、大花绣球藤(C.montanaBuch.-Ham.ex DC.var.grandifloraHook.)、毛叶威灵仙(C.chinensisOsbeck.var.vestita(Rhed.Wils.)W.T.Wang)、狭卷萼铁线莲(Clematis tubulosaTurcz.var.ichangensis(Rehd.Wils.)W.T.Wang)。订正了《河南植物志》(1981)中6个分类群的学名:将C.uncinataChamp.var.biternataW.T.Wang作为C.uncinataChamp.的异名,C.brevicaudataDC.var.filipesRhed.作为C.puberulaHook.f.et Thoms var.tenuisepala(Maxim.)W.T.Wang的异名,C.brevicaudataDC.var.tenuisepalaMaxim.作为C.puberulaHook.f.et Thoms.var.tenuisepala(Maxim.)W.T.Wang的异名,C.argentilucida(Levl.et Vant.)W.T.Wang作为C.grandidentata(Rehd.et Wils.)W.T.Wang的异名,C.obtusidentata(Rhed.et Wils.)H.Eichler作为C.apiifoliaDC.var.argentilucida(Levl.et Vant.)W.T.Wang的异名;将Clematis ternifloraDC.var.latisepalaM.C.Chang作为Clematis pashanensisvar.latisepala(M.C.Chang)W.T.Wang.的异名。     

The effect of different atmospheric ozone partial pressures on photosynthesis and growth of nine fruit and nut tree species

Nursery stock of peach (Prunus persica L. Batsch, cv. O'Henry), nectarine (P. persica L. Batsch, cv. Fantasia), plum (P. salicina Lindel., cv. Casselman), apricot (P. armeniaca L., cv. Tilton), almond (P. dulcis Mill., cv. Nonpareil), prune (P. domestica L., cv. Improved French), cherry (P. avium L., cv. Bing), oriental pear (Pyrus pyrifolia Rehd., cv. 20th Century), and apple (Malus pumula Mill., cv. Granny Smith) were planted in open-top chambers on April 1, 1988 at the University of California's Kearney Agricultural Center located in the San Joaquin Valley (30 degrees 40' N 119 degrees 40' W). Trees were exposed to three atmospheric ozone partial pressures (charcoal-filtered air (C), ambient air (A), or ambient air + ozone (T)) from August 1 to November 17, 1988. The mean 12-h (0800 to 2000 h) ozone partial pressures measured in open-top chambers during the experimental period were 0.030, 0.051, and 0.117 microPa Pa(-1) in the C, A and T treatments, respectively. Leaf net CO(2) assimilation rate decreased linearly with increasing 12-h mean ozone partial pressure for the almond, plum, apricot, prune, pear, and apple cultivars. Stomatal conductances of apricot, apple, almond, and plum decreased linearly with increasing ozone partial pressure. Cross-sectional area relative growth rates of almond, plum, apricot, and pear decreased linearly with increasing ozone partial pressure. Net CO(2) assimilation rate, stomatal conductance, and trunk growth of cherry, peach and nectarine were unaffected by the ozone treatments. Reduced leaf gas exchange probably contributed to ozone-induced growth reduction of the susceptible species and cultivars. Several of the commercial fruit tree species and cultivars studied were relatively tolerant to the ozone treatments.     

Impacts of black bear baiting on Acadian forest dynamics - An indirect edge effect?

Many biotic factors impact forest health and productivity and an important damage agent in many forests in North America is the black bear (Ursus americanus). Black bears use trees for feeding and marking purposes, both resulting in cambial damage, which reduces growth rates and can increase mortality rates. Black bear behavior is strongly impacted by human activities including forest management and supplemental feeding. During the 2010 permanent sample plot census and tree health survey in Fundy National Park, New Brunswick, Canada we measured high rates of bear damage; roughly 10% of the sampled population experienced damage in a non-uniform way within the Park. The goal of the present research was to examine the spatial distribution of bear damage, determine underlying causes of spatially non-homogeoneous bear damage and quantify the impact of this damage on forest dynamics.Bear damage was more frequent around the periphery of the Park and using spatial scan statistics, we identified two clusters of bear damage, both at the Park’s inland borders and adjacent to areas of high bear hunting baiting station density. Species differed in the extent of damage, with hardwood species incurring proportionally greater damage. Using multiple regression we modeled bear damage as a function of stand type (%hardwood), stem density, proximity to and density of bait stations and distance to the nearest major edge. Models containing stand type and bait station metrics garnered the greatest support based on minimum AIC analysis. Bear damage was greater in hardwood stands and in sites closer to or in areas of higher density of bait stations. Bear damage had a significant negative impact on forest dynamics; 2005-2010 diameter growth showed significant reductions in response to bear damage.Our findings implicate bear bait stations used by hunters in aggregating black bears at the Park periphery where they cause greater damage to the trees, which results in reduced growth rates in these areas. Effectively, high bait station densities surrounding the Park are contributing to two related edge effects: (1) increased activity in and use of forests at the Park edges by bears; and (2) increased damage and decreased growth in peripheral stands where bear activity is high. Continued heavy bear damage could pose a threat to forest integrity along the boundaries of the Park. Thus, despite the high protection afforded this National Park, its function and long-term integrity is impacted by adjacent land uses as demonstrated by the present study, an increasingly widespread problem facing protected areas.     

不同容器和基质配比对榉树容器苗营养积累的影响

【目的】榉树Zelkova schneideriana,是我国珍贵树种,它不仅材质优良,且用途广泛,经济价值较高。本试验通过比较不同容器规格和基质配比对榉树容器苗营养累积的影响,筛选出最有利于榉树容器苗营养积累的容器规格和基质配比,为榉树容器苗的高效培育提供理论和实践依据。【方法】本研究采用双因素随机区组试验设计。试验设置了两个因素即不同配比的苗圃土、农林废弃物(主要成分为农作物秸秆)、珍珠岩组成的基质,以及不同类型和规格的容器。通过对不同基质配比和容器规格影响下榉树容器苗的生物量、非结构性碳水化合物浓度、蛋白质浓度、全碳、全氮等矿质元素浓度等指标的测定分析,揭示基质配比、容器规格以及两因素的交互作用对榉树容器苗营养积累的影响。【结果】试验结果如下:在生物量方面,基质M2(90%农林废弃物+10%珍珠岩)最有利于榉树容器苗生物量(111.19 g)的积累,基质M3(45%苗圃土+45%农林废弃物+10%珍珠岩)、M5(25%苗圃土+65%农林废弃物+10%珍珠岩)次之;容器C1(30 cm×30 cm的黑色塑料控根容器)最有利于榉树容器苗生物量(148.20 g)的积累,容器C2(20 cm×30 cm的黑色塑料控根容器)次之。在非结构性碳水化合物浓度方面,基质M1(90%苗圃土+10%珍珠岩)、M2处理下的榉树容器苗中可溶性糖等指标浓度较高;容器C1处理下的可溶性糖(88.029 mg/g)等指标浓度最高,C2次之。在蛋白质浓度方面,基质M5处理下的榉树容器苗中蛋白质浓度(2.59 mg/g)最高,M1、M2、M3次之;容器C1处理下的蛋白质浓度(2.77 mg/g)最高,C2、C4(20 cm×20 cm的普通无纺布容器)次之。在矿质元素方面,基质M2和M5处理下榉树容器苗中全碳等指标浓度较高;容器C1处理下的全碳等指标浓度(9.18 mg/g)最高,C2次之。【结论】综上所述,基质M2(90%农林废弃物+10%珍珠岩)和容器C2(20 cm×30 cm的黑色塑料控根容器)的组合,最适合榉树容器苗的营养积累。     

棕黑疣螈种组分子系统发育分析及大围山疣螈新种描述

采用贝叶斯法对棕黑疣螈种组13个个体的线粒体DNA ND2基因重建了系统发育关系,结果表明,（1）该种组物种形成1个单系群;（2）红瘰疣螈不是棕黑疣螈的同物异名,支持红瘰疣螈物种地位的有效性;（3）采自云南省红河州屏边县大围山的2个标本与红瘰疣螈亲缘关系较近,并构成姐妹群,其种间遗传距离已达到种级水平。其地理居群物种为一未描述新种,定名为大围山疣螈。新种的主要鉴别特征为,前肢长于后肢或后肢略长;头部和前后臂为棕黑色,颞部和指、趾端为棕黄色。     

BUCHBESPRECHUNGEN

Book Reviewed in this article: Dässlir , H. G.; Bortiiz , S., 1988: Air Pollution and its Influence on Vegetation. Sakai , A.; Larcmer , W.: Frost Survival of Plants . Responses and adaptation to freezing stress. Eeologieal Studies 62. Roll -Hansi , N.F.; Roll -Hanshn , H.: Skogskader i farger (Forest Injuries in Colour). Hartmann , G.; Nienhaus , F.; Butin , H.: Farbatlas Waldschäden . Sembdner , G.; Schneider , G.; Schreiber , K. (Hrsg.): Methoden zur Pflanzenhormonanalyse . Hutchinson , T.C.; Meema , K. M. (eds.): Effects of Atmospheric Pollutants on Forest, Wetlands and Agricultural Ecosystems. Sachs , L.: Statistische Methoden: Planung und Auswertung. Vegh , L.: Champignons des arbres et arbustes d'ornement. Moser , M.; Jülich , W. (unter Mitarbeit von C. FURRER-ZIOGAS): Farbatlas der Basidiomyceten. Rottman , M.: Wind-und Sturmschäden im Wald. Michel ., E.; Henning B.; Kreisel , H.: Handbuch für Pilzfreunde. 46. Deutsche Pflanzenschutz-Tagung. Regensburg, 3.-7 Okt. 1988. Mitteilungen aus der Biologischen Bundesanstalt fiir Land- und Forstwirtschalt Berlin-Dahlem. Fieft 245. Hegenauer , R.: Chemotaxonomie der Pflanzen. Mattson , W. J.; Levieux , J.; Bernard -Dagan , C. (eds.): Mechanisms of Woody Plant Defenses Against Insects. Moser , M.; Julich , W. (unter Mitarbeit von C. Furricr -Ziogas ): Farbatlas dcr Basidio-myceten.     

乌桕金带蛾新种记述(鳞翅目:带蛾科)

本文为贵州省的重要林木害虫－乌桕金带蛾的新种记述，与近缘种中华金带蛾详加比较，附有特征图以兹鉴别。     

竹子新害虫竹笋绒茎蝇的鉴定(双翅目:茎蝇科)

双翅目(Diptera)的茎蝇科(Psilidae)为无瓣蝇类(Acalyptratae)中的一个小类群,已知百余种分布在世界各地区,但以全北区为主。茎蝇科的幼虫是植食性的,为害多种植物的茎、干、根等,并常造成虫瘿,可能成为农、林、果、蔬及花卉等的潜在害虫,欧洲广布的胡萝卜茎蝇(carrot fly)就是一例。     

Dependence of needle architecture and chemical composition on canopy light availability in three North American Pinus species with contrasting needle length

Morphology and chemical composition of needles of shade-intolerant southern conifers (Pinus palustris Mill. (mean needle length +/- SD = 29.1 +/- 4.1 cm), P. taeda L. (12.3 +/- 2.9 cm) and P. virginiana Mill. (5.1 +/- 0.8 cm)) were studied to test the hypothesis that foliage acclimation potential to canopy light gradients is generally low for shade-intolerant species, and in particular, because of mechanical limitations, in species with longer needles. Plasticity for each needle variable was defined as the slope of the foliar characteristic versus irradiance relationship. A novel geometrical model for needle area and volume calculation was employed for the three-needled species P. palustris and P. taeda. Needle thickness (T) strongly increased, but width (W) was less variable with increasing daily integrated quantum flux density averaged over the season (Q(int)), resulting in changes in cross-sectional needle shape that were manifested in a positive relationship between the total to projected needle area ratio (A(T)/A(P)) and Q(int) in the three-needled species. In contrast, cross-sectional needle geometry was only slightly modified by irradiance in the two-needled conifer P. virginiana. Needle dry mass per unit total needle area (M(T)) was positively related to Q(int) in all species, leading to greater foliar nitrogen contents per unit area at higher irradiances. Separate examination of the components of M(T) (density (D) and the volume (V) to A(T) ratio; M(T) = DV/A(T)) indicated that the positive effect of light on M(T) resulted solely from increases in V/A(T), i.e., from increases in the thickness of foliage elements. Foliar chlorophyll content per unit mass increased with increasing Q(int), allowing an improvement in light-harvesting efficiency in low light. The variables characterizing needle material properties (D, the dry to fresh mass ratio, and needle carbon content per unit mass) were generally independent of Q(int), suggesting that needles were less stiff and had greater tip deflections under their own weight at lower irradiances because of smaller W and T. Comparisons with the literature revealed that plasticity in foliar characteristics tended to be lower in the studied shade- intolerant species than in shade-tolerant conifers, but plasticity among the investigated species was unaffected by needle length. However, we argue that, because of mechanical limitations, plastic changes in needle cross section in response to low irradiance may decrease rather than increase light-interception efficiency in long-needled species.     

Size-mediated tree transpiration along soil drainage gradients in a boreal black spruce forest wildfire chronosequence

Boreal forests are crucial to climate change predictions because of their large land area and ability to sequester and store carbon, which is controlled by water availability. Heterogeneity of these forests is predicted to increase with climate change through more frequent wildfires, warmer, longer growing seasons and potential drainage of forested wetlands. This study aims at quantifying controls over tree transpiration with drainage condition, stand age and species in a central Canadian black spruce boreal forest. Heat dissipation sensors were installed in 2007 and data were collected through 2008 on 118 trees (69 Picea mariana (Mill.) Britton, Sterns & Poggenb. (black spruce), 25 Populus tremuloides Michx. (trembling aspen), 19 Pinus banksiana Lamb. (jack pine), 3 Larix laricina (Du Roi) K. Koch (tamarack) and 2 Salix spp. (willow)) at four stand ages (18, 43, 77 and 157 years old) each containing a well- and poorly-drained stand. Transpiration estimates from sap flux were expressed per unit xylem area, J(S), per unit ground area, E(C) and per unit leaf area, E(L), using sapwood (A(S)) and leaf (A(L)) area calculated from stand- and species-specific allometry. Soil drainage differences in transpiration were variable; only the 43- and 157-year-old poorly-drained stands had?～?50% higher total stand E(C) than well-drained locations. Total stand E(C) tended to decrease with stand age after an initial increase between the 18- and 43-year-old stands. Soil drainage differences in transpiration were controlled primarily by short-term physiological drivers such as vapor pressure deficit and soil moisture whereas stand age differences were controlled by successional species shifts and changes in tree size (i.e., A(S)). Future predictions of boreal climate change must include stand age, species and soil drainage heterogeneity to avoid biased estimates of forest water loss and latent energy exchanges.     

Seasonal changes in nodular nitrogenase activity of Alnus glutinosa and Elaeagnus angustifolia

Root nodule development, and seasonal patterns of nodular nitrogenase and hydrogenase activities were determined for 5- to 8-year old black alder (Alnus glutinosa (L.) Gaertn.) and Russian olive (Elaeagnus angustifolia L.) interplanted with black walnut (Juglans nigra L.) on bottomland and upland sites in central Illinois, USA. Black alder produced nodules at both sites, but Russian olive did so only at the bottomland site. Nodular nitrogenase activity was detectable in both species over a 220-day period. Maximum, midday rates of nitrogenase activity (acetylene reduction) of 15 to 20 micromoles C(2)H(4) per g dry nodule per hour were maintained by black alder for approximately 150 days at both the upland and bottomland sites. Near maximum rates of nodular nitrogenase activity were maintained for a similar period by Russian olive at the lowland site, although specific nitrogenase activity was approximately 25% lower than in black alder owing to a larger proportion of necrotic nodular tissue in Russian olive. In both species, nitrogenase activity increased exponentially with temperature between 10 degrees C and 20 to 25 degrees C. No net hydrogen evolution by nodules of either species was detected at any time during the assay period, indicating efficient hydrogenase systems were operating under the conditions of the field assay. Height of black walnut interplanted with nodulated black alder and Russian olive was greater than that of black walnut grown in pure stands.     

国外产竹种子形态特征及其育苗技术

测定分析了10种国外产竹种子的形态特征,并对他们进行育苗试验。结果表明：种子形状多为卵形、长锥形、椭球形,颜色以黄褐色、褐色、褐黑色为主,长度和直径分别为4~60 mm和0.9~5.5 mm;果实一般为圆锥形、锥形、卵形,颜色以灰褐色、灰色为主,长度和直径分别为5~64 mm和1.2~7.5 mm;大藤竹种子播种品质指标最好,具有最高的纯净度（97.4%）、千粒质量（201.0 g）、发芽率（95.4%）、发芽势（51.5%）、含水量（9.3%）、生活力（98.8%）及较低的病虫害感染度（6.5%）;有机质是有效提高各竹种出苗率的首选基质;宜采用先撒播种子,待胚苗有1~3片叶时再移入营养袋培育的育苗方式;育苗时施用氮磷钾复合肥,并在苗木离地50 cm处进行封顶处理,能有效促进苗木生长。     

刺槐优良无性系耐碱盐特性研究

从选定的刺槐优良无性系中选取W013,W009,C003,W038,W041等5个速生的优良无系,W037作为较差表现对比,石林作为对照进行盆栽抗盐试验。设置中性盐B1,NaCl:Na_2SO_4(1:1);碱性盐B2,NaHCO_3:Na_2CO_3(1:1);混合盐碱B3,NaCl:Na_2SO_4:NaCO_3:Na_2CO_3(1:1:1:1)3组。每组设置3个浓度梯度,Al:3g/L,A2:5g/L,A3:7g/L,分别测定其形态及生理生化指标并分析。结果表明:耐盐碱特性大小为W013,W009,C003石林刺槐W037,W038,W041,其中W013,W009,C003在7g/L仍表现出较强的耐盐碱特性。     

两种危害松类的新叶蜂(膜翅目, 广腰亚目, 松叶蜂科)

本文记述了中国松叶蜂昆虫两新种,马尾松吉松叶蜂和油松吉松叶蜂。文中附有形态特征图4幅。     

造林密度对毛红椿等阔叶用材树种早期生长的影响

开展了毛红椿(Toona ciliata var. pubescens)、光皮桦(Betula luminifera)、乳源木莲(Manglietia yuyuanensis)、杂交马褂木(Liriodendron chinense.× L.tulipifera)、桤木(Alnus cremastogyne)和南酸枣(Choerospondias axillaria)6种优良阔叶用材树1 666、2 500、3 333株/hm~23种造林密度试验,对4年生林分的观测结果显示:造林密度为1 666株/hm~2桤木林分胸径显著高于造林密度为3 333株/hm~2和2 500株/hm~2的桤木林分;造林密度对其它各树种各生长指标的影响不显著.光皮桦和桤木的生长较快,乳源木莲生长最慢.研究认为,以培育中、大径材为目的的用材林,光皮桦、桤木初植密度宜定在1 666株/hm~2;毛红椿、杂交马褂木、南酸枣初植密度以1 666株/hm~2和2 500株/hm~2为宜,乳源木莲则以2 500株/hm~2和3 333株/hm~2为宜.     

Post-harvest Regeneration of Lowland Black Spruce Forests in Northeastern Ontario

Success of natural regeneration has been a concern since the introduction of heavy machinery in harvesting. The objective was to compare the effect of three operational harvest methods careful logging around advanced growth (CLAAG), group seed tree (GST), and group seed tree followed by shearblading site preparation (SHE) on natural regeneration in the Clay Belt region of Ontario. A total of 30 stands, 562 cluster sample plots, were surveyed. Total density of black spruce regeneration did not differ, but height structure of black spruce regeneration did among harvest methods. The CLAAG method resulted in highest total regeneration density of other conifers. Decreasing density of other conifers from the CLAAG to GST to SHE sites indicated that the CLAAG method protected advance regeneration as expected and the SHE method removed advance regeneration in the path of the shearing blade. Both black spruce and other conifer regeneration densities increased with increasing time since harvest. Stocking of black spruce, all conifers, or all tree species did not differ significantly among harvest methods, nor did it change with time since harvest. Stocking was nonlinearly related to regeneration density. Models developed in this study predict that full stocking (i.e., 60%) can be reached based on regeneration density of 5000 stems per ha regardless of crop species choice preference. However, the existing stocking criterion for assessing black spruce regeneration may be problematic.