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基于红外相机监测的汪清自然保护区东北豹种群动态 总被引：1，自引：0，他引：1
【目的】东北豹是分布最北、种群数量最小的豹亚种,濒危等级为“极危”。分析采用相机监测技术得到的汪清保护区内东北豹种群数量和分布情况的长期动态,为这一濒危物种的保护提供科学依据。【方法】 2013年秋-2017年秋,在汪清保护区内东北豹主要分布区以每3km×3km网格1对的密度布设相机。采用相对丰富度指数(relative abundance indices,RAI)计算东北豹相对丰富度,以99%核密度等值线定义东北豹分布区,在Extract Compare软件中进行个体识别。在CAPTURE软件中对有效监测期的数据进行闭合种群检验、适宜模型评估和种群数量估计。以8 km为半径,在相机布设处向周边外延绘制缓冲区作为有效监测面积,评估东北豹种群密度。【结果】在9个监测季,东北豹RAI指数波动在0.34~2.12之间。2013年秋季东北豹分布区为201km^2, 2017年秋季分布区为992 km 2。共识别东北豹个体9只,其中成年雌性和雄性各3只、幼崽2只、性别不明个体1只。在种群数量低的情况下,CAPTURE闭合种群检验效力并不强,检验结果总体偏低。Mh模型(假设拍摄率有个体差异)选择标准得分在2015春、2015秋、2016秋、2017春4个监测季最高,在其他5个监测季得分仅次于M 0(假设拍摄率一致)。卡方拟合优度检验显示,Mb(假设捕获前后拍摄率有差异)、Mt(假设不同时段拍摄率有差异)模型评估捕获率与M0模型无显著差异。研究期间东北豹种群密度波动在0.12~0.88只·(100 km 2)^-1 ,种群总捕获率整体较高,但2017年春季拍摄个体仅占种群评估数量的0.43。【结论】受地理因素和猎物丰富度变化影响,东北豹时空分布具有异质性。CAPTURE闭合种群检验对小样本检验效力不强。M h假设是进行东北豹种群数量评估的适宜模型,“拍摄羞怯反应”会导致种群密度评估结果偏高。 相似文献
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黑龙江省东北虎野外种群监测研究 总被引：10，自引：0，他引：10
2003～2004年,在黑龙江省建立了东北虎监测网络系统,共记录到东北虎活动足迹链等信息25个。监测结果表明,黑龙江省东北虎目前分布于完达山东部、老爷岭南部和张广才岭南部3个独立的分布区,东北虎的数量在9～11只之间,其中完达山东部5～6只（1～2♂,2♀,2幼体）,老爷岭南部3～4只（1～2♂,1♀,1亚成体）,张广才岭南部1只（1♂）。在完达山东部乌苏里江流域的中俄边境地带存在东北虎迁移生态通道;老爷岭南部的中俄边境与吉林省交界地带有东北虎跨境迁移活动,并发现亚成体;完达山东部是黑龙江省东北虎最适宜的栖息地,并且存在东北虎的繁殖个体,是东北虎种群恢复和增长最具潜力的林区。 相似文献
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红外触发相机在荒漠区野生动物监测中的应用——以安西极旱荒漠自然保护区为例 总被引：1，自引：0，他引：1
2012年6月至2013年4月,安西极旱荒漠自然保护区采用红外触发自动相机开展保护区野生动物的监测研究,在20个位点共拍摄到有效照片2 517张,获取有效独立照片732张,其中47.4%为兽类,50.8%为鸟类,1.8%为工作人员。应用监测照片共鉴定出物种25种,其中兽类8种,鸟类17种。兽类中拍摄率最高的前3种依次为北山羊、岩羊、中亚兔;鸟类中拍摄率最高的前3种依次为红嘴山鸦、岩鸽、石鸡。并分析讨论了红外触发相机在保护区监测应用中的一些常见问题和优缺点,为红外相机在荒漠区野生动物的监测研究提供科学方法。 相似文献
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2012年6月至2013年4月,在安西板旱荒漠自然保护区采用红外触发自动相机开展保护区野生动物的监测研究,在20个位点共拍摄到有效照片2517张,获取有效独立照片732张,其中47．4％为兽类,50．8％为鸟类,1．8％为工作人员。应用监测照片共鉴定出物种25种,其中兽类8种,鸟类17种。兽类中拍摄率最高的前3种依次为北山羊、岩羊、中亚兔;鸟类中拍摄率最高的前3种依次为红嘴山鸦、岩鸽、石鸡。分析讨论了红外触发相机在保护区监测应用中的一些常见问题和优缺点。 相似文献
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2010年冬季在完达山东部林区东北虎分布区开展东北虎猎物种群野外调查,收集狍、野猪和马鹿新鲜足迹数,再结合2004年冬季野外调查收集的足迹信息,比较分析该区域猎物种群丰富度变化趋势;并通过东北虎监测、野外调查以及卫星影像资料分析导致东北虎猎物种群丰富度下降的因素.研究结果表明,狍相对丰富度年平均递减率为6.12％,野猪年平均递减率为13.13％,马鹿的年平均递减率为37.30％.栖息地面积减少及其破碎化、东北虎捕食以及人为盗猎活动均是导致东北虎猎物种群下降的关键因素. 相似文献
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红外相机是监测野生动物的有效工具,目前广泛用于兽类资源调查以及动物损害、鸟巢生态学、种群评估、行为生态学等研究领域。为了更科学地调查无量山国家级自然保护区南涧段的野生动物种类本底,2016年12月—2021年12月,采用红外相机对辖区内的野生动物进行系统调查,在86个位点放置了红外相机,一个月收取一次数据。目前,红外相机共记录到兽类19种,约占无量山记录有分布的兽类物种总数的15%;鸟类75种,约占记录有分布的鸟类物种总数的20%。 相似文献
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<正>目前,红外相机技术已发展成为陆生兽类、地面活动鸟类资源调查和监测研究的重要常规技术。红外相机主要通过照片和视频来记录并获取野生动物的种类及其群体大小、分布(相机位点信息)、拍摄照片数、行为(重点为活动节律)、生境(植被、海拔等)等数据。这些数据有助于从种群、群落和行为等方面来分析野生动物在监测区域的基本特征。然而,获得这些数据必须建立标准的红外相机调查规范要求,在布设红外相机时遵循相应的注意事项。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):427-435
In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(3):206-217
The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage. 相似文献
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Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and
also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the
amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter
bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K
was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed
significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week−1 for leaves and from 0.0225 to 0.0633 week−1 for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed
during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly
between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species
provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient
enrichment capacity and slower decomposition rates which would minimize leaching losses.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(2):118-130
The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions. 相似文献
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Steven Maranz Amadou Niang Antoine Kalinganire Djeneba Konaté Bocary Kaya 《Agroforestry Systems》2008,72(3):231-239
Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional
data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral
contents and B1 and B2 vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising
germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B1 88 mg 100 g−1, B2 187 mg 100 g−1, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal
diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties
to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations. 相似文献
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《Wood material science & engineering》2013,8(2):76-84
Abstract Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists. 相似文献
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Astra Zaluma Lauma Bruna Darta Klavina Natalija Burnevica Kristine Kenigsvalde Andis Lazdins Talis Gaitnieks 《Forest Pathology》2019,49(6)
Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):53-61
This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):15-27
The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions. 相似文献
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本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。 相似文献