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1.
贵州代化西部大标关纳缪尔晚期三叶虫   总被引:1,自引:0,他引:1  
袁金良 《古生物学报》1996,35(5):575-590
记述贵州代化西部大标关纳缪尔晚期地层(滑石板组)中的砑头虫科、短额虫科和菲利普虫科三叶虫5属(亚属)、4种和2未定种,其中有1新亚属:Microphillipsia,3新种(新亚种):Microphillipsia cylindrica,Neogriffithides daihuaensis和Weania librovitchi qiannanensis。  相似文献   

2.
兰科盆距兰属(Gastrochilus)植物的修订   总被引:1,自引:0,他引:1  
吉占和   《广西植物》1996,16(2):123-154
本文对盆距兰属(Gastrochilus)植物作了修订,共分3个组,含46种和1变种,其中1个组(Sect.Caespitosi)和8个种(G.carnsus,G.garhwalensis,G.linearifolius,G.guangtungensis,G.subpapillosus,G.nanchuanensis,G.saccatusandG.gongshanensis)为新的,首次在本文作了描述报导。本属属的形态特征,研究历史和订正后属下的分类群检索表,种的文献引证、简短的特征记要和地理分布以及在属中被排除的分类单位索引均提供在本文。  相似文献   

3.
不同环境条件下沙生植物的CO2气体交换研究   总被引:9,自引:1,他引:9  
对腾格里沙坡头地区两种沙生植物:油蒿(ArtemisisaordosicaKrasch.)和柠条(CaraganakorshinskiiKom)。在旱季和雨季时CO2气体交换特点及其动态变化进行了研究,结果表明:在干旱条件下,油蒿(A)和柠条(C)的光合作用均受到严重影响,其光合率率日变化日出后(7:00-9:a.m.)有一较小高峰外,基本处于很低水平。降水后,A和C的光合作用均明显提高,但Pn  相似文献   

4.
哀牢山木果石栎群落优势种的生态位宽度与重叠   总被引:24,自引:0,他引:24  
通过多种方法比较研究了哀牢山木果石栎(Lithocarpus xylocarpus)群落8个优势种的生态位宽度和重叠,结果表明,该群落是以木果石栎、腾冲栲(Castanopsis wattii)、滇木荷(Schima noronhae)和景东石栎(Lithocarpus chintungensis)为优势种的共优群落,它们的生态位宽度值分别为0.8732,0.7856,0.6742和0.5798。  相似文献   

5.
微量元素锗对四种微藻光合色素的影响   总被引:3,自引:0,他引:3  
采用溶液培养方法,以锗作为胁迫因子,研究了锗对4种微藻“钝顶螺旋藻(Spirulina platensis)、盐生杜氏藻(Dunaliella salina)、淇江叉鞭金藻(Dicrateria zhanjiangensis)和微绿藻(Nannochloropsis.sp)光合色素的影响。实验结果表明,经10mg/dm^3锗处理后,四种藻类细胞中的光合色素都发生了较大变化,有些色素发生明显的增加或  相似文献   

6.
部分裸子植物叶片总蛋白分析   总被引:1,自引:0,他引:1  
王艇  苏应娟  黄超  朱建明   《广西植物》1999,19(4):367-372
采用SDS- PAGE 技术, 分析了红豆杉科(Taxaceae) 植物南方红豆杉( Taxus chinensisvar- mairei (Lemee et Levl-) Cheng et L-K-Fu) 、穗花杉( Amentotaxus argotaenia (Hance) Pil ger) 、云南穗花杉( A- yunnanensis Li) 、白豆杉( Pseudotaxuschienii(Cheng) Cheng) 以及三尖杉科(Cephalotaxaceae) 、植物三尖杉( Cephalotaxus fortunei Hook-f-) 、粗榧( C-sinensis (Rehd-etWils-) Li) 、海南粗榧( C-hainanensis Li) 、篦子三尖杉( C-oliveri Mast-) 和罗汉松科(Podocarpaceae) 、植 物罗汉松 ( Podocarpus macrophyllus ( Thunb- ) D-Don) 、鸡毛 松( P-imbricatus Bl-) 、竹柏( P- nagi(Thunb-) Zoll) 、陆均松( Dacrydium pierrei Hickel) 共12 种植物的叶片蛋白, 在蛋白质水平上采用  相似文献   

7.
以UC19为母体,克隆了Bt ken-Ag(B。.thruingiensis subsp.kenyae Ag)的复制起始区(~1.6kb)、pUC4K的aph1基因,构建成穿梭载体pHV-1,pHV-1在E.coli中经100个世代,质粒保持率在80%以Bti 4Q8(B.thuringiensis subsp.israelensis 4Q8)中经40个世代,质粒保持率在80%以上,将B.lich  相似文献   

8.
红豆杉科植物RAPD分析及其系统学意义   总被引:23,自引:2,他引:21  
王艇  黄超 《西北植物学报》2000,20(2):243-249
利用随机扩增多态性DNA(RAPD)技术分析了红豆杉科(Taxaceae)红豆杉属(Taxus)、白豆杉属(Pseudotaxus)、穗花杉属(Amentotaxus)和榧树属(Torreya)的6种植物:红豆杉(Taxus chinensis (Pilger)Rehd)、南方红豆杉(Taxus chinensis var.mairei(Lemee etLevl.)Cheng etMaireYew  相似文献   

9.
新疆南部莎车奇自拉夫组晚泥盆世孢子组合及孢粉相研究   总被引:7,自引:1,他引:6  
新疆南部莎车县奇自拉夫组产孢子24属56种(含10新种),可分为两个孢子组合带:即:Leiotriletes microthelis-Punctatisporite irrasus(MI)带和Apiculiretussispora rasissima-Retispora lepidophyta(RL)带。RL带又进一步细分为两个亚带,即下部的Retispora lepidophyta-Ancyro  相似文献   

10.
湘中锡矿山邵东组和孟公坳组共产小孢子45属83种(含10个新种,3个新联合),可划分为4个孢子组合,即:Retisporalepidophyta-Apiculiretusisporafructicosa(LF)组合,Rugosporacf.flexuosa-Retisporalepidophyta(FL)组合,LophozonotriIetesexcisus-Retisporalepidophyta(EL)组合和Crassisporacf.kosankei-Lycosporadenticulata(KD)组合。根据孢子组合的特征,泥盆-石炭系界线置于EL与KD组合之间,即相当于孟公坳组中下部与上部之间。  相似文献   

11.
Because hunting disturbance can influence local distribution of ducks and their availability to hunters, managers often limit access to hunting areas to improve hunting success and satisfaction. Few studies have quantified the effectiveness of public area access restrictions on duck hunter activity, harvest, or hunters' satisfaction with their hunting experience. We used a cross-over design over 6 consecutive hunting seasons (2008–2009 through 2013–2014) on State Wildlife Areas (SWAs) in northeastern Colorado, USA, to compare the effects of restricted hunting access regulations and regulations without these restrictions on duck hunter activity, harvest success, harvest levels, and satisfaction. We also considered effects of SWA types, duck abundance, temperature, precipitation, use of equipment by duck hunting parties, and, for hunter satisfaction, hunting success, hunting parties' satisfaction with ducks seen, habitat conditions, crowding from other hunters, and SWA regulations. The number of days when duck hunters had access to restricted properties was about half that on unrestricted properties, and unrestricted properties were used by about twice as many duck hunting parties, but the mean number of hunting parties per available hunting day and mean party size were similar under the 2 types of regulations. Most (56%) duck hunting parties did not bag any ducks; hunting success (harvest of ≥1 duck by a hunting party) was best explained by a model that included a regulation type × hunting season interaction, a SWA type × month interaction, hunter density the previous day, an index of hunter investment (number of decoys used and whether dogs and calls were used), and temperature. Successful hunting parties harvested 1.92 ± 1.60 (SD) ducks/hunter/day (range = 0.1–7.0); the best model predicting the number of ducks harvested per hunter in successful parties included a regulation type × hunting season interaction, a SWA type × month interaction, hunter density the previous day, an index of hunter investment, temperature, and precipitation. Overall satisfaction of duck hunting parties with a day's hunt averaged 3.62 ± 1.20 based on a rank scale of 1 (very unsatisfied) to 5 (very satisfied), and was best explained by a model that included hunting party success; hunter investment; temperature; and satisfaction with duck numbers, habitat conditions, hunting regulations, and crowding. While greatly reducing days available for hunting, access restrictions were associated with improved chances of hunting parties successfully harvesting ≥1 duck in 5 of 6 hunting seasons, and substantially greater numbers of ducks harvested by hunters in successful parties in 1 of 6 hunting seasons. Restrictions did not have a strong direct effect on hunting parties' satisfaction with a day's hunt. Uncontrolled factors, including weather and use of equipment by hunters, had important influences on hunter success, harvest, and satisfaction. Managers should carefully assess hunting activity, hunter expectations and desires, and hunting area characteristics when considering access restrictions on public hunting areas.  相似文献   

12.
We weighed hunter-killed mallards (Anas platyrhynchos; n = 4,747) during the 2005, 2008, and 2009 hunting seasons in Manitoba, Minnesota, North Dakota, Saskatchewan, and South Dakota to examine effects of hunting pressure on body mass. Our final model indicated that main effects describing age, hunting pressure, hunting method, season, relative harvest date, and selected interactions were influential in predicting mass of drake mallards during fall. Body mass of hatch-year and after-hatch-year drake mallards harvested in low hunting pressure jurisdictions was 4.3% and 2.5% greater, respectively, than those harvested in high hunting pressure jurisdictions. Body mass of drake mallards from low hunting pressure jurisdictions was 12.1% greater for birds that were harvested using pass or jump shooting hunting methods than those that were harvested by hunters using decoys over dry agricultural fields. When possible, managers should consider disturbance during planning stages of attracting mallards, and not rely upon dry agricultural fields as foraging resources for mallards unless a positive energy balance can be achieved. Finally, studies examining physiological condition of waterfowl must account for collection technique. © 2012 The Wildlife Society.  相似文献   

13.
Yiming L  Zhengjun W  Duncan RP 《Oecologia》2006,148(1):129-136
Islands are often considered easier to invade than mainland locations because of lower biotic resistance, but this hypothesis is difficult to test. We compared invasion success (the probability of establishing a wild reproducing population) for bullfrogs (Rana catesbeiana) introduced to enclosures on 26 farms on islands in the Zhoushan archipelago and 15 farms in neighboring mainland China. Bullfrogs were more likely to invade farms located on islands with lower native frog species richness than mainland farms, consistent with the biotic resistance hypothesis. However, human frog hunting pressure also differed between islands and the mainland and, along with the number of bullfrogs raised in enclosures, was a stronger predictor of invasion success than native frog richness in multiple regression. Variation in hunting pressure was also able to account for the difference in invasion success between islands and mainlands: islands had lower hunting pressure and thus higher invasion probability. We conclude that the ease with which bullfrogs have invaded islands of the Zhoushan archipelago relative to the mainland has little to do with biotic resistance but results from variation in factors under human control.Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   

14.
Subsistence hunting among the Waimiri Atroari Indians in central Amazonia, Brazil, was studied from September 1993 to October 1994 to assess the current levels of resource exploitation. Hunting effort, harvesting yields and species composition of the hunt were recorded daily in five villages varying in number of people, location and age of the settlement. The Waimiri Atroari harvested a total of 3004 individuals of 41 species in one year. Lowland tapir (Tapirus terrestris), white-lipped peccary (Tayassu pecari), collared peccary (T. tajacu) and spider monkey (Ateles paniscus) represented 87% of the total yearly game weight. Sex ratios of spider monkeys killed were heavily biased towards females indicating a stronger hunting pressure on those individuals. Harvesting yields was proportional to hunting efforts indicating no evident game depletion in the study period. However, capture per unit of effort was significantly different among villages. Differences in total game mass harvested may be explained by local resource depletion associated with age and size of the settlement. However, this relationship is confounded by the capacity of some villages to exploit distant hunting sites. Data obtained in one village showed that harvest rates were higher in hunting sites located far from settlement indicating game depletion in hunting sites surrounding the village.  相似文献   

15.
Human harvests can select against phenotypes favoured by natural selection, and natural resource managers should evaluate possible artificial selection on wild populations. Because the required genetic data are extremely difficult to gather, however, managers typically rely on harvested animals to document temporal trends. It is usually unknown whether these data are unbiased. We explore our ability to detect a decline in horn size of bighorn sheep (Ovis canadensis) by comparing harvested males with all males in a population where evolutionary changes owing to trophy hunting were previously reported. Hunting records underestimated the temporal decline, partly because of an increasing proportion of rams that could not be harvested because their horns were smaller than the threshold set by hunting regulations. If harvests are selective, temporal trends measured from harvest records will underestimate the magnitude of changes in wild populations.  相似文献   

16.
Abstract We analyzed harvest data to describe hunting patterns and harvest demography of brown bears (Ursus arctos) killed in 3 geographic regions in Sweden during 1981–2004. In addition, we investigated the effects of a ban on baiting, instituted in 2001, and 2 major changes in the quota system: a switch to sex-specific quotas in 1992 and a return to total quotas in 1999. Brown bears (n=887) were harvested specifically by bear hunters and incidentally by moose (Alces alces) hunters. Both hunter categories harvested bears 1) using dogs (37%), 2) by still hunting (30%), 3) with the use of bait (18%), and 4) by stalking (16%). The proportion of bears killed with different harvest methods varied among regions and between bear- and moose-oriented hunters. We found differences between male (52%) and female bears (48%) with respect to the variables that explained age. Moose-oriented hunters using still hunting harvested the youngest male bears. Bears harvested during the first management period (1981–1991) were older and had greater odds of being male than during the subsequent period. It appears that hunters harvesting bears in Sweden are less selective than their North American counterparts, possibly due to differences in the hunting system. When comparing the 4 years immediately prior to the ban on baiting with the 4 years following the ban, we found no differences in average age of harvested bears, sex ratio, or proportion of bears killed with stalking, still hunting, and hunting with dogs, suggesting that the ban on baiting in Sweden had no immediate effect on patterns of brown bear harvest demography and remaining hunting methods. As the demographic and evolutionary side effects of selective harvesting receive growing attention, wildlife managers should be aware that differences in harvest systems between jurisdictions may cause qualitative and quantitative differences in harvest biases. (JOURNAL OF WILDLIFE MANAGEMENT 72(1):79–88; 2008)  相似文献   

17.
Hunting is one of the human activities that directly affect wildlife and has received increasing attention given its socioeconomic dimensions. Most studies have been conducted on coastal and wetland areas and showed that hunting activity can greatly affect bird behaviour and distribution. Hunting-free reserves for game species are zones where birds find an area of reduced disturbance. We evaluated the effect of hunting activities on the behaviour and use of hunting-free areas of lapwings Vanellus vanellus , golden plovers Pluvialis apricaria and little bustards Tetrax tetrax in agricultural areas. We compared the habitat use and behaviour of birds on days before, during and after hunting took place. All three studied species showed strong behavioural responses to hunting activities. Hunting activity increased flight probability and time spent vigilant (higher on hunting days than just before and after a hunting day), to the detriment of resting. We also found distributional (use of hunting-free reserve) responses to hunting activities, with hunting-free reserves being used more frequently during hunting days. Thus, reserves can mitigate the disturbance caused by hunting activities, benefiting threatened species in agricultural areas. Increasing the size or number of hunting-free areas might be an important management and conservation tool to reduce the impacts of hunting activities.  相似文献   

18.
Sport hunting may help in controlling cervid populations over large areas. As with natural predators, several environmental factors can influence sport harvest. A better understanding of the environmental variables that limit the efficiency of sport hunting could provide guidelines for more efficient wildlife management using hunting. We studied white-tailed deer (Odocoileus virginianus) hunting on a high deer density island where hunting was the sole form of predation. Our objective was to study the behavior of sport hunters and determine the habitat characteristics (e.g., abundance of deer forage, visibility of the deer from the hunter's point of view, and accessibility of the territory to hunters) that are associated with a successful harvest. We collected movements and harvest site location data from 477 hunters equipped with handheld Global Positioning System (GPS) units. Harvest sites were visited and characterized, along with a paired random site, to determine the environmental conditions associated with a successful hunt. We also developed a model to predict the daily number of deer seen by hunters considering weather conditions, hunter characteristics (e.g., age, experience), and date of hunting. We used the mean number of deer seen per hunter per day as a relative index of local density in each hunted territory. At both the site and landscape scales, the combination of visibility and access had a positive effect on the distribution of harvested deer. Habitat types with less visual obstruction from vegetation enabled hunters to see more deer in a given day. At the site scale, harvested deer were located in areas with a lower density of access routes compared to areas where hunters travelled throughout the day. Using an innovative approach of studying hunter behavior with GPS technology, digital maps, and questionnaires, we highlighted the factors associated with hunter success. Our study suggests that habitat characteristics could be modified to increase harvest by improving accessibility and visibility near roads. Creating openings in mature and regenerating forest near access roads could make sport hunting a more efficient management tool, but the potential impact of increased forage availability in forest openings should not be overlooked. © 2012 The Wildlife Society.  相似文献   

19.
Ethnozoological research was conducted to gather information on the hunting activities and their relevance for the subsistence of local people in 8 villages around the game reserve of Gile, Mozambique. Two series of data were gathered by questionnaires to: (a) 510 householders from eight villages located in the outskirts of the Reserve; (b) 10 hunters from the village of Gile, the main centre of the study area. Several hunting techniques were recorded: spears, nets, traps (including gin-traps) and wildfires, while the use of guns did not appear relevant. The importance of subsistence hunting for local people was underlined by the high percentage of respondents who declared that they usually conduct this activity and sell bushmeat. The proportion of hunters per village was related to the village size but not to its geographical location of villages and the household composition. A positive relationship existed between the proportion of hunters, crop production and fishing activities, indicating that hunting is part of an integrated system of subsistence activities. Most animals harvested were mammals (89.5%, of which 46.7% were ungulates) and most were captured within the Reserve (96%). A higher percentage of animals was sold (56%), representing a relevant income source for the villagers. Small animals were mainly captured by traps during solitary hunting, medium-sized animals in collective net hunting; larger prey were captured by gin-traps adopted by both solitary and collective hunting. In the diet of the local people wild animals represented a higher protein source than domestic animals.  相似文献   

20.
甘肃阿克塞县哈尔腾国际狩猎场野生动物资源丰富,主要狩猎动物盘羊和岩羊。通过狩猎,推动了阿克塞县野生动物保护事业的发展。目前,猎场存在草场超载、放牧管理不合理、狩猎地固定、多头管理、利益分配等问题。为实现该猎场的可持续经营,应控制羊群规模、调整转场时间、调整狩猎区域、开展野生动物资源监测、加强各部门的协调、提高工作效率和透明度。  相似文献   

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