Results 31 to 40 of about 17,222 (205)

内蒙古贺兰山马鹿的种群数量及种群结构

open access: yes野生动物学报, 2021
为了掌握内蒙古贺兰山国家级自然保护区内马鹿(Cervus elaphus)的种群数量和种群结构,维护内蒙古贺兰山的生态平衡。于2017年11—12月,2018年4—6月、11—12月,2019年4—6月,在内蒙古贺兰山国家级自然保护区内,利用样线法对保护区内的马鹿进行调查,采用Distance R进行数据分析,估测种群数量和种群密度,并对种群结构进行探讨。研究发现,马鹿在2018年冬季种群数量最高约为2452(1678—3578)只,种群密度为3705(2539—5048)只/km2,遇见率为1 ...
孙萍黄师梅苏云孟德怀张致荣滕丽微刘振生
doaj  

大头鲤原种种群的遗传现状 [PDF]

open access: yes, 2012
大头鲤(Cyprinus pellegrini)是一种云南高原湖泊特有的国家Ⅱ级重点保护鱼类。土著种大头鲤与外来种鲤(C.carpio)的渐渗杂交在星云湖野生种群中已经广泛发生。本研究结合形态和微卫星及线粒体DNA分析检测了螺蛳铺大头鲤原种种群的遗传现状。结果显示,螺蛳铺大头鲤样本所有个体在形态上位于大头鲤与鲤的参照样本之间;在微卫星因子对应分析中也显示,其位于大头鲤与鲤的参照样本之间,但与大头鲤参照样本较为相似;在线粒体DNA分析中显示,都具有鲤的单倍型 ...
唐卫星, 陈毅峰
core  

Jellyfish blooms restructure plankton dynamics and trophic linkages in coastal waters

open access: yesFunctional Ecology, EarlyView.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Jellyfish blooms are increasing globally in frequency and intensity, introducing complex ecological interactions, yet the mechanisms by which they alter ecosystem structure remain poorly characterized due to a lack of sustained field observations.
Pengpeng Wang   +4 more
wiley   +1 more source

Multi‐barcoding‐based species identification using a hierarchical attention network with staged curriculum learning

open access: yesMethods in Ecology and Evolution, EarlyView.
Abstract DNA barcode‐based species identification has become pivotal in biodiversity research. Current barcoding‐based deep learning methods have advantages in species identification but exhibit significant limitations. By using COI barcoding alone, previous studies were unable to fully capture species identification features. Prior methods showed that
Bin Ye   +4 more
wiley   +1 more source

海南坡鹿迁地保护现状与建议

open access: yes野生动物学报, 2007
迁地保护的海南坡鹿种群可以分为野放、半野放和圈养等3种主要类型。野放种群个体数量最多,约占迁地保护种群个体总数的55.3%;其次为半野放种群,其个体数量占35.6%;圈养种群个体数量最少,只占9.1%。半野放是一种较为稳妥的坡鹿种群恢复方式。在海南坡鹿的迁地保护中,应该增加半野放种群个体数量。本文就海南坡鹿的迁地保护提出了7点保护管理及科学研究建议。
卢学理, 袁喜才, 李善元, 张海
doaj  

Use of species’ responses to cryptic anthropogenic disturbances for monitoring biodiversity outcomes in tropical forests

open access: yesConservation Biology, EarlyView.
Abstract Measuring area‐based conservation outcomes in tropical forests is challenging due to cryptic human disturbances (e.g., hunting). As a result, comparative studies of management strategies providing quantitative outcomes remain scarce, especially in the Neotropics.
Lucy Perera‐Romero   +5 more
wiley   +1 more source

中国黑叶猴圈养种群现状分析

open access: yes野生动物学报, 2014
应用种群管理软件SPARKS 1.6及PMX对中国黑叶猴圈养种群的现状进行了统计分析。截至2012年12月31日,黑叶猴谱系记录了574只个体,目前种群存活个体数量为318只,分布在34家动物园或机构中。圈养种群野外捕获个体主要来源于20世纪70~90年代,目前保持稳定状态。圈养出生个体数则一直保持上升状态,是维持黑叶猴圈养种群增长的主要来源,2012年圈养出生数量占种群总数的87.4%。种群周期增长率λ=1.042,性比M:F=1:1.04,目前种群中能够繁殖的个体共110只(♂48只,♀62只 ...
高喜凤
doaj  

中国麋鹿种群现状分析及保护对策探讨

open access: yes野生动物学报, 2020
麋鹿自1985年重引进中国以来,经过繁殖扩群、行为再塑和野生放养试验3个阶段后,种群数量从79头发展至近7 000头(2018年底),先后形成江苏大丰、湖北石首和湖南洞庭湖野生麋鹿种群。通过对中国麋鹿种群发展现状调查分析,指出目前麋鹿种群健康发展面临的挑战和威胁因素,在扩大奠基种群数量、实施栖息地正向干预、加强疫病防控、开展基因交流等方面探讨中国麋鹿种群健康发展对策。
王立波 1 姜 慧 2 安玉亭 2 杨禹治 3 原宝东 4
doaj  

温带荒漠中温度和土壤水分对土壤呼吸的影响 [PDF]

open access: yes, 2009
荒漠对气候变化具有高度敏感性,深刻认识和量化非生物因子对荒漠生态系统土壤呼吸的影响具有重要意义。采用自动CO2通量系统(Li-8100)监测了梭梭(Haloxylon ammodendron)、假木贼(Anabasis aphylla)和盐穗木(Halostachys caspica)群落生长季土壤呼吸及温度、土壤含水量等,深入分析了水热因子对土壤呼吸的影响。土壤呼吸具有不对称的日格局,最小值出现在8:00,最大值在12:00~14:00。土壤呼吸的季节格局与气温变化基本同步,最小值在生长季末期(10月)
张丽华   +3 more
core  

Using miniaturized laboratory equipment and DNA barcoding to improve conservation genetics training and identify illegally traded species

open access: yesConservation Biology, EarlyView.
Abstract Illegal wildlife trade (IWT) is one of the largest global illegal activities, and it negatively affects biodiversity and sustainable development worldwide. DNA barcoding coupled with high‐throughput sequencing (i.e., metabarcoding) is useful in identifying taxa affected by IWT and has been used routinely for decades.
Maria Joana Ferreira da Silva   +9 more
wiley   +1 more source

Home - About - Disclaimer - Privacy