海狸在几项研究中对野生动物中的微量元素(TE)进行了分析;但是,这些研究大多是在已知环境污染物的地区进行的。为了了解和量化海狸组织中TE的自然富集,肾脏样本,肝脏,将28只动物的肌肉与40种树木和灌木的树皮进行了比较,从相同的,未被污染的分水岭。皮尔逊相关和因子分析显示,亲石元素,如Al,Ga,Th,Y,所有矿物尘埃颗粒的替代品,解释了树皮数据中61%的变异。相比之下,Cd,Co,Cu,Mn,Mo,Ni,Rb,Se,Sr,树皮中的Tl独立于Al,因此,最有可能以非矿物形式出现。比较海狸和树皮的组织浓度,器官富含微量营养素,如铜,Fe,Mo,Se,Zn,但也是非必需的,良性元素,如Cs和Rb,以及Cd和Tl等潜在有毒元素。因此,海狸器官中最丰富的元素是那些在植物组织中以生物形式出现的元素。这些动物中丰富的元素,相对于树皮,似乎为使用海狸监测TEs的环境污染提供了最大的希望。与环境相关的大多数TE在海狸肾中最丰富。然而,监测研究必须考虑海狸组织中TE浓度的变化,包括性别和年龄。此外,必须充分考虑构成动物饮食的植被中TEs的背景浓度。自然富集在Cd等元素的情况下,在海狸组织中相对于树皮,是深刻的。这些数据为未污染环境中海狸的TEs建立了关键基线值,从而允许它们作为模式生物用于追踪重金属污染物如何影响野生动物。
Beavers have been analyzed in several studies examining trace elements (TEs) in wildlife; however, most of these studies were undertaken in areas with known environmental pollutants. To understand and quantify natural enrichments of TEs in
beaver tissue, samples of kidney, liver, muscle from 28 animals were compared with bark from 40 species of trees and shrubs, from the same, uncontaminated watershed. Pearson correlation and factor analysis show that conservative, lithophile elements such as Al, Ga, Th, and Y, all surrogates for mineral dust particles, explain 61% of the variation in the bark data. In contrast, Cd, Co, Cu, Mn, Mo, Ni, Rb, Se, Sr, and Tl in bark are independent of Al, and therefore most likely occur in non-mineral forms. Comparing tissue concentrations of
beaver and bark, the organs are enriched in micronutrients such as Cu, Fe, Mo, Se, and Zn, but also non-essential, benign elements such as Cs and Rb, and potentially toxic elements such as Cd and Tl. Thus, the elements most enriched in
beaver organs are those that apparently occur in biological form in the plant tissue. The elements enriched in these animals, relative to bark, appear to offer the most promise for monitoring environmental contamination by TEs using beavers. The majority of TEs of environmental relevance are most abundant in
beaver kidney. However, monitoring studies must consider the variation in TE concentrations in
beaver tissue, including those due to sex and age. Also, due consideration must be given to background concentrations of TEs in the vegetation composing the diet of the animals. The natural enrichment in the case of elements such as Cd, in beaver tissue relative to bark, is profound. These data establish critical baseline values for TEs in beavers in an unpolluted environment, thereby allowing for their use as model organisms in tracking how heavy metal pollutants may affect wildlife.