Climatic conditions associated with successful perennial grass recruitment events in south-eastern Australia

Research output: Book chapter/Published conference paperConference paper

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Abstract

Recruitment of new perennial grass plants within existing ecosystems is determined by seed availability, suitable microsites, resources and climatic conditions. This paper reports on the modelled soil moisture conditions associated with successful recruitment events in five field experiments at Orange (Phalaris aquatica), Trunkey Creek (Austrodanthonia spp.) and Wellington (Bothriochloa macra) in Central New South Wales (NSW), and the frequency of those conditions during the past 30 years. High seedling numbers were recorded when mature germinable seed was present and when a rainfall event (median 68 mm across the three sites) kept the surface soil moisture (0-50 mm) above the permanent wilting point for at least 15 days. Rainfall events typically occurred in the second half of February, sometimes extending to early March. No recruitment occurred if the surface soil was only moist for 7 days or less. The past data (1975 - 2004) showed that Orange had a median of 20 moist days each year at this time, whereas it was 16 days for Trunkey Creek and 10 days for Wellington. The probabilities of exceeding 7 or 15 days of moist surface soil were 98% and 78% at Orange, 91% and 49% at Trunkey Creek, and 73% and 30% at Wellington. These results show some recruitment is possible in most years, provided seasonal conditions enable adequate seed set over summer.
Original languageEnglish
Title of host publication15th AAC
Subtitle of host publicationFood security from sustainable agriculture
EditorsH. Dove, R.A. Culvenor
Place of PublicationAustralia
PublisherThe Regional Institute
Pages1-6
Number of pages6
Publication statusPublished - 2010
EventAustralian Agronomy Conference - Lincoln, New Zealand, New Zealand
Duration: 15 Nov 201018 Nov 2010

Conference

ConferenceAustralian Agronomy Conference
CountryNew Zealand
Period15/11/1018/11/10

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grass
soil surface
soil moisture
seed
rainfall
wilting
seed set
seedling
ecosystem
summer
resource
creek
field experiment

Cite this

Thapa, R., & Kemp, D. (2010). Climatic conditions associated with successful perennial grass recruitment events in south-eastern Australia. In H. Dove, & R. A. Culvenor (Eds.), 15th AAC: Food security from sustainable agriculture (pp. 1-6). Australia: The Regional Institute.
Thapa, Roshan ; Kemp, David. / Climatic conditions associated with successful perennial grass recruitment events in south-eastern Australia. 15th AAC: Food security from sustainable agriculture. editor / H. Dove ; R.A. Culvenor. Australia : The Regional Institute, 2010. pp. 1-6
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abstract = "Recruitment of new perennial grass plants within existing ecosystems is determined by seed availability, suitable microsites, resources and climatic conditions. This paper reports on the modelled soil moisture conditions associated with successful recruitment events in five field experiments at Orange (Phalaris aquatica), Trunkey Creek (Austrodanthonia spp.) and Wellington (Bothriochloa macra) in Central New South Wales (NSW), and the frequency of those conditions during the past 30 years. High seedling numbers were recorded when mature germinable seed was present and when a rainfall event (median 68 mm across the three sites) kept the surface soil moisture (0-50 mm) above the permanent wilting point for at least 15 days. Rainfall events typically occurred in the second half of February, sometimes extending to early March. No recruitment occurred if the surface soil was only moist for 7 days or less. The past data (1975 - 2004) showed that Orange had a median of 20 moist days each year at this time, whereas it was 16 days for Trunkey Creek and 10 days for Wellington. The probabilities of exceeding 7 or 15 days of moist surface soil were 98{\%} and 78{\%} at Orange, 91{\%} and 49{\%} at Trunkey Creek, and 73{\%} and 30{\%} at Wellington. These results show some recruitment is possible in most years, provided seasonal conditions enable adequate seed set over summer.",
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Thapa, R & Kemp, D 2010, Climatic conditions associated with successful perennial grass recruitment events in south-eastern Australia. in H Dove & RA Culvenor (eds), 15th AAC: Food security from sustainable agriculture. The Regional Institute, Australia, pp. 1-6, Australian Agronomy Conference, New Zealand, 15/11/10.

Climatic conditions associated with successful perennial grass recruitment events in south-eastern Australia. / Thapa, Roshan; Kemp, David.

15th AAC: Food security from sustainable agriculture. ed. / H. Dove; R.A. Culvenor. Australia : The Regional Institute, 2010. p. 1-6.

Research output: Book chapter/Published conference paperConference paper

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T1 - Climatic conditions associated with successful perennial grass recruitment events in south-eastern Australia

AU - Thapa, Roshan

AU - Kemp, David

N1 - Imported on 03 May 2017 - DigiTool details were: publisher = Australia: The Regional Institute, 2010. editor/s (773b) = H Dove and R A Culvenor; Event dates (773o) = 15-18 November 2010; Parent title (773t) = Australian Agronomy Conference.

PY - 2010

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N2 - Recruitment of new perennial grass plants within existing ecosystems is determined by seed availability, suitable microsites, resources and climatic conditions. This paper reports on the modelled soil moisture conditions associated with successful recruitment events in five field experiments at Orange (Phalaris aquatica), Trunkey Creek (Austrodanthonia spp.) and Wellington (Bothriochloa macra) in Central New South Wales (NSW), and the frequency of those conditions during the past 30 years. High seedling numbers were recorded when mature germinable seed was present and when a rainfall event (median 68 mm across the three sites) kept the surface soil moisture (0-50 mm) above the permanent wilting point for at least 15 days. Rainfall events typically occurred in the second half of February, sometimes extending to early March. No recruitment occurred if the surface soil was only moist for 7 days or less. The past data (1975 - 2004) showed that Orange had a median of 20 moist days each year at this time, whereas it was 16 days for Trunkey Creek and 10 days for Wellington. The probabilities of exceeding 7 or 15 days of moist surface soil were 98% and 78% at Orange, 91% and 49% at Trunkey Creek, and 73% and 30% at Wellington. These results show some recruitment is possible in most years, provided seasonal conditions enable adequate seed set over summer.

AB - Recruitment of new perennial grass plants within existing ecosystems is determined by seed availability, suitable microsites, resources and climatic conditions. This paper reports on the modelled soil moisture conditions associated with successful recruitment events in five field experiments at Orange (Phalaris aquatica), Trunkey Creek (Austrodanthonia spp.) and Wellington (Bothriochloa macra) in Central New South Wales (NSW), and the frequency of those conditions during the past 30 years. High seedling numbers were recorded when mature germinable seed was present and when a rainfall event (median 68 mm across the three sites) kept the surface soil moisture (0-50 mm) above the permanent wilting point for at least 15 days. Rainfall events typically occurred in the second half of February, sometimes extending to early March. No recruitment occurred if the surface soil was only moist for 7 days or less. The past data (1975 - 2004) showed that Orange had a median of 20 moist days each year at this time, whereas it was 16 days for Trunkey Creek and 10 days for Wellington. The probabilities of exceeding 7 or 15 days of moist surface soil were 98% and 78% at Orange, 91% and 49% at Trunkey Creek, and 73% and 30% at Wellington. These results show some recruitment is possible in most years, provided seasonal conditions enable adequate seed set over summer.

KW - Open access version available

KW - Drought

KW - Irrigation

KW - Late summer

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KW - Perennial grasses

KW - Soil moisture

M3 - Conference paper

SP - 1

EP - 6

BT - 15th AAC

A2 - Dove, H.

A2 - Culvenor, R.A.

PB - The Regional Institute

CY - Australia

ER -

Thapa R, Kemp D. Climatic conditions associated with successful perennial grass recruitment events in south-eastern Australia. In Dove H, Culvenor RA, editors, 15th AAC: Food security from sustainable agriculture. Australia: The Regional Institute. 2010. p. 1-6