Managing pollutant inputs from pastoral dairy farming to maintain water quality of a lake in a high-rainfall catchment

被引：11

作者：

Wilcock, Robert J. ^{[1
]}

Monaghan, Ross M. ^{[2
]}

McDowell, Richard W. ^{[2
]}

Verburg, Piet ^{[1
]}

Horrox, Jonny ^{[3
]}

Chague-Goff, Catherine ^{[4
,5
]}

Duncan, Maurice J. ^{[6
]}

Rutherford, Alison ^{[2
]}

Zemansky, Gil ^{[7
]}

Scarsbrook, Mike R. ^{[8
]}

Wright-Stow, Aslan E. ^{[1
]}

Howard-Williams, Clive ^{[6
]}

Cotton, Sue

机构：

[1] Natl Inst Water & Atmospher Res, Hamilton, New Zealand

[2] AgResearch, Invermay Agr Ctr, Mosgiel, New Zealand

[3] West Coast Reg Council, Greymouth, New Zealand

[4] Univ New S Wales, Sch Biol Earth & Environm Sci, Sydney, NSW 2052, Australia

[5] Australian Nucl Sci & Technol Org, Kirrawee Dc, NSW 2232, Australia

[6] Natl Inst Water & Atmospher Res, Christchurch, New Zealand

[7] Geol & Nucl Sci, Taupo, New Zealand

[8] DairyNZ Ltd, Hamilton, New Zealand

来源：

MARINE AND FRESHWATER RESEARCH | 2013年 / 64卷 / 05期

关键词：

catchment yield; flood frequency; groundwater; nutrients; sediment; NEW-ZEALAND RIVERS; INCHBONNIE CATCHMENT; HOLLOWED SOILS; WEST-COAST; PHOSPHORUS; SEDIMENT; LOSSES; STREAM; STATE;

D O I：

10.1071/MF12296

中图分类号：

S9 [水产、渔业];

学科分类号：

0908 ;

摘要：

A study (2004-11) of a dairy catchment stream entering an oligotrophic lake in an area of very high rainfall (similar to 5m year(-1)) yielded median concentrations of total nitrogen (TN), total phosphorus (TP), suspended sediment (SS) and Escherichia coli (E. coli) of 0.584, 0.074 and 3.7 gm(-3), and 405/100mL (most probable number method), respectively. Trend analysis indicated significant (P < 0.01) decreases for TN (-0.08 +/- 0.02 gm(-3) year(-1)), TP (-0.01 +/- 0.005 gm(-3) year(-1)) and SS (-0.45 +/- 0.14 gm(-3) year(-1)) and were partly attributable to improved exclusion of cattle from the stream. Water balance calculations indicated that approximately one-half the rainfall left as deep drainage that by-passed catchment outlet flow recorders. Estimates of catchment yields for TN were improved by taking into account groundwater hydrology and concentrations from well samples. Storm-flow monitoring inflows exceeding the 97.5th percentile contributed similar to 40% of total loads leaving the catchment so that specific yields for SS, TN and TP augmented by groundwater inputs and storm flows were,960, 45 and 7 kg ha(-1) year(-1), respectively. These compared well with modelled results for losses from dairy farms in the catchment of 40-60 kgNha(-1) year(-1) and 5-6 kg P ha(-1) year(-1) and indicated that attenuation losses were relatively small.

引用

页码：447 / 459

页数：13