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1.
印度野牛是西双版纳热带森林生态系统的代表性物种,历史上印度野牛广布于西双版纳,在过去的30年间,随着人口增加,人类干扰的加剧,印度野牛生境破碎化和丧失严重,其种群面临灭绝。为了解印度野牛在西双版纳现有分布区域和数量情况,于2013年1月至2014年8月,采用访问调查法对西双版纳州印度野牛分布范围及种群数量开展调查。结果表明,印度野牛分布于勐腊县上中良村,勐腊自然保护区南贡山,尚勇保护区南满村、河图二组;勐海县帕迫村、中纳包村、南罕上寨、星火山村,曼派村,曼麻榜村,纳京六组,南双岭村、贺建八组、纳板河自然保护区,曼兴梁村;景洪市勐养镇勐养自然保护区澜沧江沿线、龙帕村、巴来村、巴卡老寨区域。印度野牛的分布区域在逐渐萎缩,数量在逐渐减少,由1988年的605~712头减少到目前的152~167头,前景堪忧。建议加强对印度野牛的基础研究与保护。  相似文献   

2.
印度野牛是一种濒危的大型哺乳动物,其全球种群在过去的100年内发生了显著的下降,分布区也发生了剧烈的缩减。在中国,云南西双版纳是印度野牛现存种群的主要分布区。由于历史上遭受过较强的捕猎和栖息地破坏,该物种保护面临严峻危机。为了解该地印度野牛的生境利用特征,为该种群的保护提供一定依据,2014年7月—2015年11月,对西双版纳勐满地区的一个印度野牛群体开展了野外监测,通过收集到的野牛群位点统计了其家域面积,分析了海拔、植被和地形对其生境利用的影响。结果显示,该地区的印度野牛利用的家域面积为10~20 km2,利用的海拔范围为1 299~1 848 m,偏好森林覆盖率高且平坦的区域,在迁移时可能会利用平坦但森林覆盖率较低的区域。  相似文献   

3.
在西双版纳全州范围选择了167个点(村寨)进行访问调查,并布设16条调查监测样线开展野外调查,同时在16条样线上安装80台次的红外相机全天候监测。结果显示,除访问调查在2011—2016年间有4次发现绿孔雀身影,样线调查及红外相机监测均未发现其痕迹。据此推断,近年来最有可能分布绿孔雀的区域是勐宋村曼播散洞中缅边境一线,而且在缅甸一侧可能存在一个绿孔雀小种群。根据绿孔雀种群致危因子分析,提出恢复生境、减少农药使用等保护建议。  相似文献   

4.
在西双版纳傣族自治州全州采用半结构访谈法、样线法和红外相机技术相结合的方法,对猕猴、熊猴、北豚尾猴、短尾猴、菲氏叶猴等5种猴科动物种群进行调查。结果显示:猕猴在全州3县市所有乡/镇(街道办)均有分布;熊猴分布于勐养、勐遮、勐混、勐仑等乡镇;北豚尾猴分布于勐遮、勐混、易武、勐仑、勐腊等乡镇;短尾猴分布于勐海、勐仑等乡镇;菲氏叶猴分布于允景洪、勐养、勐旺、勐遮、勐腊、勐仑等乡镇。运用ArcMap10.2.2软件进行筛选过滤,测算出猴科动物潜在分布面积约为32.02万hm2,分布海拔在480~2200 m,种群规模约在 3470~ 4740 只。热带雨林、热带季雨林、亚热带常绿阔叶林、落叶阔叶林、暖性针叶林、竹林、灌木林等7种植被类型均有猴科动物分布。针对猴科动物保护面临的生境破碎化、林下经济发展导致生境质量下降、被猎杀等威胁,提出加强栖息地保护、关注笼养猴科动物福利、严肃查处非法猎杀行为、开展科学研究和加强宣传力度等保护建议。  相似文献   

5.
综合采用线路调查法和红外触发相机调查法,对长青保护区内的林麝及其活动痕迹进行分析总结,结果表明:陕西长青国家级自然保护区林麝(Moschus berezovskii)喜欢在针阔混交林、中等海拔、坡度较陡、西南或南向的区域活动,其主要分布区为大坪和柏杨坪片区,次要分布区为杨家沟、石塔河、东坪和九池等地;林麝种群稳步发展,柄息地持续恢复,但仍显岛屿状、零星化分布特点.严格控制保护区内的人为活动,是林麝及其栖息地保护和恢复的基本对策.  相似文献   

6.
采用半结构访谈法、样线调查法和红外相机技术对西双版纳傣族自治州自然保护区、国有及集体天然林所分布的北豚尾猴进行系统调查。结果显示:北豚尾猴共有15~20个种群,约300~500只,分布于勐遮、勐混、易武、勐仑、勐腊等乡镇,且主要集中在自然保护区及天然林分布区,分布海拔为700~2 000 m,所涉及的植被类型有热带雨林、热带季雨林、亚热带常绿阔叶林、落叶阔叶林4种。针对存在的生境破碎化、林下经济作物种植、非法猎杀等问题,提出保护栖息地、严肃查处非法猎杀行为、开展科研监测和宣传教育等北豚尾猴保护措施。  相似文献   

7.
2017年1—12月,采用红外相机对云南省新平县野生绿孔雀开展调查监测。在野生绿孔雀潜在分布区共布设96台红外相机,累计工作日11 482个,共捕获2 873张独立有效照片,记录到野生兽类5目7科8种,鸟类5目9科12种。在布设的96个红外相机位点中有37个位点拍摄到野生绿孔雀的图像,捕获1 370张绿孔雀独立有效照片。根据调查结果,结合3S技术,作出了绿孔雀分布图。结果显示,新平县野生绿孔雀分布于者竜、老厂、新化等5个乡镇/街道的6个片区,呈斑块状分布,且这些区域均位于保护区之外,栖息地的破碎化导致各种群间无法交流,急需开展绿孔雀栖息地保护工作。  相似文献   

8.
以千岛湖消落带植被重建区为研究区域,利用红外相机对消落带植被区内的主要野生动物进行了初步调查,结果表明:8台红外相机累计738个总有效监测日共拍摄个体独立照片83张,全部为省级一般保护动物其中野猪(Sus scrofa)照片81张,鼬獾(Melogale moschata)2张。千岛湖库区消落带植被重建后为地栖兽类活动增加了栖息空间,与自然针阔混交林相比没有差异,而在无植被的库区消落带则没有拍摄到野生动物,消落带植被重建效果初显。  相似文献   

9.
为掌握雷公山国家级自然保护区野生鸟类资源状况,采用公里网格随机布设60个红外相机监测位点,对雷公山重点区域地面活动鸟类进行调查。2020年1月至2021年12月,100台红外相机野外累计正常工作18 074个相机日,累计获得独立有效鸟类照片(视频)2 883份。调查监测记录到鸟类7目、17科、48种,其中栗苇鳽、红点颏、蓝歌鸲、斑胸钩嘴鹛、灰头绿啄木鸟、灰翅噪鹛、褐翅鸦鹃等7种为雷公山保护区鸟类新纪录。分析结果表明:鸟类相对多度最高为白鹇,其次为灰胸竹鸡和棕头鸦雀;鸟类网格占有率最高为白鹇(42.05%),棕头鸦雀(35.23%)和灰胸竹鸡(25.00%)次之。  相似文献   

10.
2017年7~12月,采用样带调查、红外相机法和访问调查的方法,对广东惠东古田省级自然保护区内野猪(Sus scrofa)种群现状进行了专项调查研究。结果表明,夏季野猪种群的平均密度为2.9~4.5头/km~2,保护区野猪个体总数量在64~99头之间,冬季野猪种群的平均密度为1.6~3.3头/km~2,保护区野猪个体总数量在35~72头之间。野猪日活动高峰期为2:00~4:00,其次为20:00~22:00。野猪主要危害果园、菜地;假人、家犬、围栏是当地村民的主要防治措施,其中假人和家犬的防治效果不明显,围栏的防治效果较为显著。  相似文献   

11.
Our study focuses on predicting the ultimate short-term load carrying capacity of timber-to-timber connections with dowel-type fasteners. The wide range of possible configurations in practice makes the resolution of these values by tests unrealistic. Moreover, different current regulations do not consider some specific failure mechanisms. In many countries, the reduction of resistance involved by this phenomenon is taken into account by considering an effective number of dowels (nef) smaller than the actual number of dowels (n) in the connection. However, these different regulations disagree on the values of nef and on other points (spacing, partial coefficient of security, formulas). These discrepancies in design rules invite the fundamental research on this topic and, therefore, new methods are sought in order to estimate the load carrying capacities of the connections. In the light of these, our approach consists of predicting the load carrying capacity with the neural network numerical tool. The results obtained by this analysis tool are satisfactory, although the model remains complex. Subsequently, we focus on the simplification of this numerical model with classical regression techniques in order to implement it in a design code.  相似文献   

12.
Ophiostoma species were isolated from bark beetles and Abies mariesii, A. veitchii and A. homolepis attacked by the beetles in Nikko, Tochigi, central Honshu, Japan. One to two Ophiostoma species were frequently isolated from each species of bark beetle. Ophiostoma subalpinum was the most common associate of Cryphalus montanus. Ophiostoma sp. B as well as O. subalpinum was a common fungus associated with Polygraphus proximus. Ophiostoma europhioides was isolated from Dryocoetes hectographus and D. autographus as one of the common associates. Ophiostoma sp. J and Ophiostoma sp. S were frequently isolated from D. autographus and D. striatus, respectively. These fungi seem to have specific relationships with particular bark beetles. Ophiostoma sp. B, Ophiostoma sp. J and Ophiostoma sp. S have unique morphological characteristics and appear to be new species. Five trees of A. veitchii, approximately 43 years old, were inoculated with five Ophiostoma species to assess the relative virulence of the fungi. Ophiostoma subalpinum, Ophiostoma sp. B, and O. europhioides had relatively higher virulence than the other species studied.  相似文献   

13.
Parasitic Hymenoptera from the suprafamily Ichneumonoidea attacking the horse chestnut leafminer Cameraria ohridella Deschka & Dimic (Lepidoptera: Gracillariidae) were studied in southwest Slovakia during 2000 and 2001. The search for such species resulted in the determination of eight ichneumonid species, Gelis agilis (Fabricius), Itoplectis alternans (Gravenhorst), I. clavicornis (Thompson), I. maculator (Fabricius), Scambus annulatus (Kiss), S. brevicornis (Gravenhorst), Zatypota percontatoria (Müller), Adelognathus sp. and a braconid Colastes braconius Haliday. The most abundant species was S. annulatus. All these species recorded are polyphagous and often facultative hyperparasitoids, except C. braconius, which departs from this norm in not being hyperparasitic. The presence of more diversified native parasitoids and hyperparasitoids from the Ichneumonoidea predicate a slow successive adaptation of the parasitoid fauna to the invasive host, Cameraria ohridella.  相似文献   

14.
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 > TithoniaEuphatorium > 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   

15.
Trees and shrubs as sources of fodder in Australia   总被引:2,自引:0,他引:2  
Experience with browse plants in Australia is briefly reviewed in terms of their forage value to animals, their economic value to the landholder and their ecological contribution to landscape stability. Of the cultivated species only two have achieved any degree of commercial acceptance (Leucaena leucocephala and Chamaecytisus palmensis). Both of these are of sufficiently high forage value to be used as the sole source of feed during seasonal periods of nutritional shortage. Both are also leguminous shrubs that establish readily from seed. It is suggested that a limitation in their present use is the reliance on stands of single species which leaves these grazing systems vulnerable to disease and insects. Grazing systems so far developed for high production and persistence of cultivated species involve short periods of intense grazing followed by long periods of recovery. Similar management may be necessary in the arid and semi-arid rangelands where palatable browse species are in decline.  相似文献   

16.
Pavela R 《Fitoterapia》2004,75(7-8):745-749
The methanol extracts of eight species of medicinal plants were tested for insecticidal activity in third instar larvae of Egyptian cottonworm (Spodoptera littoralis). All extracts showed a certain degree of larval toxicity. The extracts of Ocimum basilicum, Origanum majorana and Salvia officinalis appeared to be highly toxic. The extracts significantly affected the growth indexes [relative growth rate (RGR), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD)].  相似文献   

17.
A new norlignan, (2R,3R,4S,5S)-2,4-bis(4-hydroxyphenyl)-3,5-dihydroxy-tetrahydropyran (1), together with 9 known compounds were isolated from the branches and leaves of Taxodium ascendens. Their structures were mainly determined on the basis of MS, IR, 1D and 2D NMR spectral evidences. Methanol extract showed inhibitory activity on carbonic anhydrase II with an IC50 value of 4.27 µg/ml, acetone extract and methanol extract inhibited activity of cathepsin B with IC50 values of 2.12 and 3.71 µg/ml, respectively.  相似文献   

18.
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   

19.
Ngugi  Michael R.  Hunt  Mark A.  Doley  David  Ryan  Paul  Dart  Peter 《New Forests》2003,26(2):187-200
Effects of soil water availability on seedling growth, dry matter production and allocation were determined for Gympie (humid coastal) and Hungry Hills (dry inland) provenances of Eucalyptus cloeziana F. Muell. and for E. argophloia Blakely (dry inland) species. Seven-month-old seedlings were subjected to well-watered (100% field capacity, FC), moderate (70% FC) and severe (50% FC) soil water regimes in a glasshouse environment for 14 wk. There were significant differences in seedling growth, biomass production and allocation patterns between species. E. argophloia produced twice as much biomass at 100% FC, and more than three times as much at 70% and 50% FC than did either E. cloeziana provenance. Although the humid provenance of E. cloeziana had a greater leaf area at 100% FC conditions than did the dry provenance, total biomass production did not differ significantly. Both E. cloeziana provenances were highly sensitive to water deficits. E. argophloia allocated 10% more biomass to roots than did E. cloeziana. Allometric analyses indicated that relative biomass allocation patterns were significantly affected by genotype but not by soil water availability. These results have implications for taxon selection for cultivation in humid and subhumid regions.  相似文献   

20.
Mattsson  Stefan  Bergsten  Urban 《New Forests》2003,26(3):217-231
The aim of this study was to quantify the effects of different soil scarification methods on tree growth. Soil scarification influenced stem volume and stem biomass yield of lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) in a 17-year-old field trial in boreal Sweden. Soil scarification (disc trenching, mounding and ploughing) resulted in an average stem volume yield of 3.1 and 34.2 m3 ha–1 on the poor and intermediate sites, respectively, while corresponding values for no soil scarification were 0.9 and 16.7 m3 ha–1. In comparison to no scarification, ploughing increased volume yields by 500% on the poor site and by 200% on the intermediate sites. The ranking according to stem volume yield was ploughing > disc trenching = mounding no soil scarification. Averaged over the two sites, the mean annual increment of stem biomass was 219% and 145% higher (in d.w., 0.26 kg and 0.34 kg per sample tree) after ploughing compared with no soil scarification, for the average and dominant sample trees, respectively. Although not significant, the increased growth rate after soil scarification decreased the average stem basic wood density of the sample trees with 1.6% and 5.3%, at the poor and intermediate sites, respectively. In conclusion, soil scarification significantly increased the 17-year stem volume yield compared with no scarification. The results also indicate that the difference in stem biomass yield between ploughing and the other methods, especially no soil scarification, will increase even more in the near future.  相似文献   

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