Details
Original language | English |
---|---|
Pages (from-to) | 71-79 |
Number of pages | 9 |
Journal | Journal of hydrology |
Volume | 377 |
Issue number | 1-2 |
Publication status | Published - 20 Oct 2009 |
Abstract
The drivers of spatial throughfall heterogeneity are still not fully understood. At an undisturbed forest site in the Ecuadorian Andes with ca. 2600 mm of annual rainfall we determined the accuracy of throughfall measurements by comparing Hellmann-type funnel gauges with troughs. At the same undisturbed and a managed, selectively-logged forest site we determined spatial variability of throughfall, temporal stability of spatial variability and the controls of spatial throughfall variability using a 4-year dataset in weekly resolution. There were no systematic differences between the collected volumes of funnel gauges and troughs. Based on the statistical distribution of annual throughfall volumes, a high number of 27 funnel-type rainfall collectors were required in the undisturbed forest and 20 in the managed forest to estimate throughfall with an error of 10% and a confidence interval of 95%. Spatial throughfall variability in the studied forests was high, markedly stable during 4 years and similar in six selected rain events suggesting that a stable canopy structure controlled throughfall variability. After mathematically eliminating the canopy influence, no meteorological variable had a significant effect on throughfall variability. We conclude that the high spatial variability of throughfall in the study forest, mainly controlled by a long-term stable canopy structure, contributes to the creation of different ecological niches which are a prerequisite for the enormous biological diversity of the north Andean forests.
Keywords
- Canopy structure, Ecological niches, Hydrologic cycle, Interception, Rain gauge, Spatial variability
ASJC Scopus subject areas
- Environmental Science(all)
- Water Science and Technology
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In: Journal of hydrology, Vol. 377, No. 1-2, 20.10.2009, p. 71-79.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Spatial throughfall heterogeneity in a montane rain forest in Ecuador
T2 - Extent, temporal stability and drivers
AU - Wullaert, H.
AU - Pohlert, T.
AU - Boy, J.
AU - Valarezo, C.
AU - Wilcke, W.
N1 - Funding information: We thank the working group of Jörg Bendix and Rütger Rollenbeck for providing meteorological data and the group of Reinhard Mosandl, Michael Weber and Sven Günter for conducting the improvement fellings in the managed forest. We thank all persons who supported us in sampling. We are grateful to Katelyn Reczek for her review of the manuscript and we furthermore thank two anonymous reviewers for their constructive remarks on an earlier version of the manuscript. We are indebted to the Ministerio del Ambiente of the Republic of Ecuador for permitting the research and the Nature and Culture International in Loja, Ecuador for providing the study area and the research station. Financial support was provided by the German Research Foundation ( DFG, FOR 816, Wi 1601/8-1 ).
PY - 2009/10/20
Y1 - 2009/10/20
N2 - The drivers of spatial throughfall heterogeneity are still not fully understood. At an undisturbed forest site in the Ecuadorian Andes with ca. 2600 mm of annual rainfall we determined the accuracy of throughfall measurements by comparing Hellmann-type funnel gauges with troughs. At the same undisturbed and a managed, selectively-logged forest site we determined spatial variability of throughfall, temporal stability of spatial variability and the controls of spatial throughfall variability using a 4-year dataset in weekly resolution. There were no systematic differences between the collected volumes of funnel gauges and troughs. Based on the statistical distribution of annual throughfall volumes, a high number of 27 funnel-type rainfall collectors were required in the undisturbed forest and 20 in the managed forest to estimate throughfall with an error of 10% and a confidence interval of 95%. Spatial throughfall variability in the studied forests was high, markedly stable during 4 years and similar in six selected rain events suggesting that a stable canopy structure controlled throughfall variability. After mathematically eliminating the canopy influence, no meteorological variable had a significant effect on throughfall variability. We conclude that the high spatial variability of throughfall in the study forest, mainly controlled by a long-term stable canopy structure, contributes to the creation of different ecological niches which are a prerequisite for the enormous biological diversity of the north Andean forests.
AB - The drivers of spatial throughfall heterogeneity are still not fully understood. At an undisturbed forest site in the Ecuadorian Andes with ca. 2600 mm of annual rainfall we determined the accuracy of throughfall measurements by comparing Hellmann-type funnel gauges with troughs. At the same undisturbed and a managed, selectively-logged forest site we determined spatial variability of throughfall, temporal stability of spatial variability and the controls of spatial throughfall variability using a 4-year dataset in weekly resolution. There were no systematic differences between the collected volumes of funnel gauges and troughs. Based on the statistical distribution of annual throughfall volumes, a high number of 27 funnel-type rainfall collectors were required in the undisturbed forest and 20 in the managed forest to estimate throughfall with an error of 10% and a confidence interval of 95%. Spatial throughfall variability in the studied forests was high, markedly stable during 4 years and similar in six selected rain events suggesting that a stable canopy structure controlled throughfall variability. After mathematically eliminating the canopy influence, no meteorological variable had a significant effect on throughfall variability. We conclude that the high spatial variability of throughfall in the study forest, mainly controlled by a long-term stable canopy structure, contributes to the creation of different ecological niches which are a prerequisite for the enormous biological diversity of the north Andean forests.
KW - Canopy structure
KW - Ecological niches
KW - Hydrologic cycle
KW - Interception
KW - Rain gauge
KW - Spatial variability
UR - http://www.scopus.com/inward/record.url?scp=70349494086&partnerID=8YFLogxK
U2 - 10.1016/j.jhydrol.2009.08.001
DO - 10.1016/j.jhydrol.2009.08.001
M3 - Article
AN - SCOPUS:70349494086
VL - 377
SP - 71
EP - 79
JO - Journal of hydrology
JF - Journal of hydrology
SN - 0022-1694
IS - 1-2
ER -