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行为的结构、刚性和多样性 被引量:86
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作者 蒋志刚 李春旺 +1 位作者 彭建军 胡慧建 《生物多样性》 CAS CSCD 2001年第3期265-274,共10页
有关动物行为的定义、结构和多样性是一个被长期忽视的研究领域。然而 ,动物行为多样性不仅是一个生物多样性基础理论问题 ,也与濒危动物的成功保护有关。本文定义了动物行为以及行为的刚性与弹性 ,探讨了行为表达的空间条件以及生境因... 有关动物行为的定义、结构和多样性是一个被长期忽视的研究领域。然而 ,动物行为多样性不仅是一个生物多样性基础理论问题 ,也与濒危动物的成功保护有关。本文定义了动物行为以及行为的刚性与弹性 ,探讨了行为表达的空间条件以及生境因素与行为多样性之间的关系。我们发现雌雄大熊猫个体在较大的活动空间里的发情行为表现的频次及活动频率显著地高于那些在较小的空间里的雌雄个体 ,说明活动空间对雄性或雌性大熊猫的发情行为有显著影响。圈养空间影响麋鹿的社会行为、通讯行为和聚群行为。圈养在小圈中的麋鹿没有出现同性聚群现象 ,当圈养麋鹿野放后即表现出这种现象。圈养环境中长大的动物个体由于缺乏行为的表达空间 ,仅仅表现出刚性大的行为 ,丧失了许多弹性大的行为 ,从而导致动物行为的多样性下降。对那些生活在开阔草原和荒漠上的野生有蹄类动物实施迁地保护时 ,必须考虑其逃逸空间 ,为那些动物建立自然保护区时 ,则必须考虑其迁移空间。此外 ,动物行为的多样性与生境元素有关。我们应当给圈养动物提供复杂而多样的环境 ,以增加圈养野生动物表达寻找食物、建立领域、筑巢和避开不利环境等行为的可能性 。 展开更多
关键词 弹性行为 刚性行为 行为多样性 生境元素 逃避空间 迁徙空间 动物行为
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Influence of Soil Geochemistry to the Quality of Winter Jujube in Zhanhua 被引量:1
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作者 高宗军 王敏 +1 位作者 庞绪贵 刘中业 《Agricultural Science & Technology》 CAS 2010年第9期209-212,216,共5页
[Objective] The aim was to investigate the effects of soil geochemistry on the quality of winter jujube.[Method]Based on the data of ecological geochemical survey in lower Yellow River Basin,the relevance of the geoch... [Objective] The aim was to investigate the effects of soil geochemistry on the quality of winter jujube.[Method]Based on the data of ecological geochemical survey in lower Yellow River Basin,the relevance of the geochemistry environment in top soils and the quality of winter jujubes was analyzed.[Result]Cd,Ni and other heavy metals in the soil more obviously affected the nutrition of winter jujubes.[Conclusion]B,Mn,MgO,Cd,Zn,K2O and other elements in the root soil played an important role in the enrichment of Cr and Hg of winter jujube fruit.And the absorption of heavy metals in winter jujube root could be interfered by improving fertilization method,to reduce the enrichment of harmful elements in jujube fruit. 展开更多
关键词 Zhanhua winter jujube Ecological geochemical environment Heavy metal element
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Seasonal and spatial variations in rare earth elements and yttrium of dissolved load in the middle,lower reaches and estuary of the Minjiang River,southeastern China 被引量:1
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作者 ZHU Xuxu GAO Aiguo +5 位作者 LIN Jianjie JIAN Xing YANG Yufeng ZHANG Yanpo HOU Yuting GONG Songbai 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第3期700-716,共17页
A bstract With the aim of elucidating the spatial and seasonal behaviors of rare earth elements(REEs), we investigated the dissolved REE concentrations of surface water collected during four seasons from middle, lower... A bstract With the aim of elucidating the spatial and seasonal behaviors of rare earth elements(REEs), we investigated the dissolved REE concentrations of surface water collected during four seasons from middle, lower reaches and estuary of the Minjiang River, southeastern China. The results display that the REE abundances in Minjiang River, ranging from 3.3–785.9 ng/L, were higher than those of many of the major global rivers. The total REE concentrations(∑REE) were seasonally variable, averaging in 5 937.30, 863.79, 825.65 and 1 065.75 ng/L during second highest flow(SHF), normal flow(NF), low flow(LF) and high flow(HF) season, respectively. The R_(( L/M)) and R_((H/M)) ratios reveal the spatial and temporal variations of REE patterns, and particularly vary apparently in the maximum turbidity zone and estuary. REE patterns of dissolved loads are characterized by progressing weaker LREEs-enrichment and stronger HREEsenrichment downstream from middle reaches to estuary during all four seasons. Comparing with NF and LF seasons, in which REE patterns are relatively flat, samples of SHF season have more LREE-enriched and HREE-depleted patterns that close to parent rocks, while samples of HF season are more LREEs-depleted and HREE-enriched. REE fractionations from the middle to lower reaches are stronger in the SHF and HF seasons than those in NF and LF seasons. Generally, spatial and seasonal variations in REE abundance and pattern are presumably due to several factors, such as chemical weathering, mixture with rainfall and groundwater, estuarine mixing, runoff, biological production and mountain river characters, such as strong hydrodynamic forces and steep slopes. The highest Gd/Gd* always occurs at north ports during all four seasons, where most of the large hospitals are located. This suggests Gd anomalies are depended on the density of modern medical facilities. Y/Ho ratios fl uctuate and positively correlate to salinity in estuary, probably because of the geochemical behavior differences between Y and Ho. 展开更多
关键词 rare earth elements(REEs) Minjiang River estuarine mixing process dissolved load online pre-concentration system
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