본문 바로가기
HOME> 논문 > 논문 검색상세

논문 상세정보

Ecology v.74 no.3, 1993년, pp.826 - 839  

Holocene Variation in Spatial Scales of Vegetation Pattern in the Upper Great Lakes

Graumlich, Lisa J. ; Davis, Margaret B. ;
  • 초록  

    While continental-scale patterns of vegetation change during the Holocene clearly record the influence of climatic change, the factors governing change at the landscape scale are less clearly defined. In order to characterize the scales of processes determining vegetation patterns during the Holocene, we analyzed a network of 52 pollen sites in the upper Great Lakes region. Pollen percentage data for three dominant tree genera (pine, Pinus; oak, Quercus; birch, Betula) were interpolated from samples bracketing four target years (500, 2500, 4500, and 6500 yr BP). Smoothed isopoll maps of taxon abundance for each target year show broad trends in pollen abundance that correspond to climatic gradients. Residuals, representing the deviation of each pollen datum from the smoothed valued, indicate the amount of spatial variation in pollen abundance independent of that already modeled as a broad gradient. The three genera differ in the magnitude and pattern of residual variation. Oak residuals are relatively small in magnitude, while pine and birch residuals are relatively large and show greater local variability in sign and magnitude. This indicates local variability in tree abundance, as pollen of all three taxa is readily dispersed by wind. Spatial correlograms, which summarize the strength of spatial autocorrelation as a function of distance between pairs of sites for a given taxon, were calculated separately for each target year and allow the quantification of the dominant scale of variability of each taxon. Oak correlograms corroborate the mapped data in indicating the dominance of region-wide trends. In contrast the birch and pine correlograms indicate that factors operating at scales of 150 to 300 km are as important as region-wide trends in governing pollen abundances. The structure of the correlograms for birch and pine pollen changes through time, with birch showing a more patchy spatial pattern in the mid-Holocene (4500 and 6500 yr BP) as compared to the late-Holocene (500 and 2500 yr BP). Pine, in contrast, shows a more strongly autocorrelated pattern in the mid-Holocene. Our results suggest that substrate, an environmental constraint on vegetation at scales of tens to hundreds of kilometers, has been important in governing the spatial distribution of birch and pine in the upper Great Lakes region. The changing distribution of birch and pine is attributed, in part, to changes in the relative abundance of ecologically dissimilar species within these genera. Further, these observations suggest that spatial scales of tree abundances are dynamic and that constraints imposed by substrate vary in importance in response to long-term climatic variation.


  • 원문보기

    원문보기
    무료다운로드 유료다운로드
    • 무료 원문 정보가 존재하지 않습니다.

    유료 다운로드의 경우 해당 사이트의 정책에 따라 신규 회원가입, 로그인, 유료 구매 등이 필요할 수 있습니다. 해당 사이트에서 발생하는 귀하의 모든 정보활동은 NDSL의 서비스 정책과 무관합니다.

    NDSL에서는 해당 원문을 복사서비스하고 있습니다. 아래의 원문복사신청 또는 장바구니 담기를 통하여 원문복사서비스 이용이 가능합니다.

  • 주제어

    Betula .   climatic variation .   Holocene vegetation patterns .   landscape ecology .   Michigan .   paleoecology .   Pinus .   pollen-based vegetation reconstruction .   Quercus .   spatial autocorrelation .   spatial variation in pollen abundance .   Wisconsin.  

 활용도 분석

  • 상세보기

    amChart 영역
  • 원문보기

    amChart 영역