Spatial and temporal patterns of off-slope sediment delivery for small catchments subject to shallow landslides within the Waipaoa catchment, New Zealand

Geomorphology ◽  
2012 ◽  
Vol 141-142 ◽  
pp. 150-159 ◽  
Author(s):  
Katie E. Jones ◽  
Nicholas J. Preston
Keyword(s):  
New Zealand ◽  
Temporal Patterns ◽  
Shallow Landslides ◽  
Spatial And Temporal Patterns ◽  
Sediment Delivery ◽  
Slope Sediment ◽  
Small Catchments

scholarly journals Contemporary Sediment Delivery Ratios for Small Catchments Subject to Shallow Rainfall Triggered Earthflows in the Waipaoa Catchment, North Island, New Zealand

2021 ◽  
Author(s):  
◽  
Katie Elizabeth Jones
Keyword(s):  
River Mouth ◽  
Storm Event ◽  
Delivery Ratio ◽  
Storm Events ◽  
Spatial And Temporal Patterns ◽  
Channel Coupling ◽  
Sediment Delivery ◽  
Catchment Size ◽  
Fluvial Network ◽  
Small Catchments

<p>The Waipaoa catchment is generally considered to have high hill slope channel coupling due to the large volumes of sediment output at the river mouth. Yet the percentage of sediment that is transported within the fluvial system is low when considered in terms of the total volume of sediment mobilised during episodic failure events. Clearly, there is a discrepancy between generation of sediment and its delivery to the fluvial network. Previous research has suggested there is a strong decrease in catchment connectivity as catchment size increases. However, little research has been undertaken to understand the changes in hillslope-channel coupling over time. This study focuses on the connectivity of shallow rainfall triggered earthflows located in small catchments located within three different land systems in the Waipaoa Catchment. A multiple regression model was developed to predict the sediment delivery ratio for individual earthflows based on an empirical dataset of earthflows which occurred during a storm event in 2002. The results from this modelling were applied to five larger sub-catchments where sequential aerial photograph analysis (1940s to 2004) was used to determine connectivity. From this, spatial and temporal patterns in the catchment sediment delivery ratios were identified. The expected decrease in sediment delivery ratios was observed as catchment size increased. However, the temporal pattern to sediment delivery is not so clear. It appears that catchment evolution, referring specially to the Terrain Event Resistance Model developed by Crozier and Preston (1999), does not have a significant influence on sediment delivery ratios within the six decades examined in this thesis. Furthermore, while earthflows are considered the ultimate source of sediment during storm events, they are not always the mechanism by which this sediment enters the fluvial network. It is also vital to consider rates of gullying, sheet erosion and riparian erosion.</p>

scholarly journals Contemporary Sediment Delivery Ratios for Small Catchments Subject to Shallow Rainfall Triggered Earthflows in the Waipaoa Catchment, North Island, New Zealand

2021 ◽  
Author(s):  
◽  
Katie Elizabeth Jones
Keyword(s):  
River Mouth ◽  
Storm Event ◽  
Delivery Ratio ◽  
Storm Events ◽  
Spatial And Temporal Patterns ◽  
Channel Coupling ◽  
Sediment Delivery ◽  
Catchment Size ◽  
Fluvial Network ◽  
Small Catchments

<p>The Waipaoa catchment is generally considered to have high hill slope channel coupling due to the large volumes of sediment output at the river mouth. Yet the percentage of sediment that is transported within the fluvial system is low when considered in terms of the total volume of sediment mobilised during episodic failure events. Clearly, there is a discrepancy between generation of sediment and its delivery to the fluvial network. Previous research has suggested there is a strong decrease in catchment connectivity as catchment size increases. However, little research has been undertaken to understand the changes in hillslope-channel coupling over time. This study focuses on the connectivity of shallow rainfall triggered earthflows located in small catchments located within three different land systems in the Waipaoa Catchment. A multiple regression model was developed to predict the sediment delivery ratio for individual earthflows based on an empirical dataset of earthflows which occurred during a storm event in 2002. The results from this modelling were applied to five larger sub-catchments where sequential aerial photograph analysis (1940s to 2004) was used to determine connectivity. From this, spatial and temporal patterns in the catchment sediment delivery ratios were identified. The expected decrease in sediment delivery ratios was observed as catchment size increased. However, the temporal pattern to sediment delivery is not so clear. It appears that catchment evolution, referring specially to the Terrain Event Resistance Model developed by Crozier and Preston (1999), does not have a significant influence on sediment delivery ratios within the six decades examined in this thesis. Furthermore, while earthflows are considered the ultimate source of sediment during storm events, they are not always the mechanism by which this sediment enters the fluvial network. It is also vital to consider rates of gullying, sheet erosion and riparian erosion.</p>

Spatial and Temporal Patterns of Campylobacter Contamination Underlying Public Health Risk in the Taieri River, New Zealand

2003 ◽  
Vol 32 (5) ◽  
pp. 1820-1828 ◽  
Author(s):  
Rebekah Eyles ◽  
Dev Niyogi ◽  
Colin Townsend ◽  
George Benwell ◽  
Philip Weinstein
Keyword(s):  
Public Health ◽  
New Zealand ◽  
Health Risk ◽  
Temporal Patterns ◽  
Spatial And Temporal Patterns ◽  
Public Health Risk

SPATIAL AND TEMPORAL PATTERNS OF GROUNDWATER ELEVATION AND SALINITY ON ASSATEAGUE ISLAND

2016 ◽  
Author(s):  
Ruth Coffey ◽  
◽  
Hannah Sprinkle ◽  
Eric Sherry ◽  
Brian Sturgis ◽  
...  
Keyword(s):  
Temporal Patterns ◽  
Spatial And Temporal Patterns ◽  
Assateague Island

THE NEW RADIOCARBON DATASET FOR TRILITH MONUMENTS OF SOUTHEASTERN ARABIA

Radiocarbon ◽  
2020 ◽  
pp. 1-11
Author(s):  
R Garba ◽  
P Demján ◽  
I Svetlik ◽  
D Dreslerová
Keyword(s):  
Iron Age ◽  
Temporal Patterns ◽  
Temporal Analysis ◽  
Coastal Plains ◽  
Spatial And Temporal Patterns ◽  
Two Phase ◽  
Stone Monuments ◽  
South Central ◽  
Geographical Expansion ◽  
Spatio Temporal

ABSTRACT Triliths are megalithic monuments scattered across the coastal plains of southern and southeastern Arabia. They consist of aligned standing stones with a parallel row of large hearths and form a space, the meaning of which is undoubtedly significant but nonetheless still unknown. This paper presents a new radiocarbon (14C) dataset acquired during the two field seasons 2018–2019 of the TSMO (Trilith Stone Monuments of Oman) project which investigated the spatial and temporal patterns of the triliths. The excavation and sampling of trilith hearths across Oman yielded a dataset of 30 new 14C dates, extending the use of trilith monuments to as early as the Iron Age III period (600–300 BC). The earlier dates are linked to two-phase trilith sites in south-central Oman. The three 14C pairs collected from the two-phase trilith sites indicated gaps between the trilith construction phases from 35 to 475 years (2 σ). The preliminary spatio-temporal analysis shows the geographical expansion of populations using trilith monuments during the 5th to 1st century BC and a later pull back in the 1st and 2nd century AD. The new 14C dataset for trilith sites will help towards a better understanding of Iron Age communities in southeastern Arabia.

Sign in / Sign up

Export Citation Format

Share Document