NZGA: Research and Practice Series最新文献_第4页

The resilience of soil organic carbon stocks under contrasting hill country pasture management practices 对比丘陵牧场管理方式下土壤有机碳储量的恢复力

NZGA: Research and Practice Series Pub Date : 2021-07-11 DOI: 10.33584/RPS.17.2021.3449

A. Mackay, R. Vibart, C. McKenzie, B. Devantier, Emma Noakes

{"title":"The resilience of soil organic carbon stocks under contrasting hill country pasture management practices","authors":"A. Mackay, R. Vibart, C. McKenzie, B. Devantier, Emma Noakes","doi":"10.33584/RPS.17.2021.3449","DOIUrl":"https://doi.org/10.33584/RPS.17.2021.3449","url":null,"abstract":"In 2020 we measured the stability of soil organic carbon (SOC) concentrations and stocks under contrasting hill country pasture regimes, by sampling three slope classes and three aspect locations on each of three farmlets of a long-term phosphorus fertiliser and sheep grazing experiment. The farmlets included no annual phosphorus (NF), 125 kg of single superphosphate/ha (LF), or 375 kg superphosphate/ha (HF) that has been applied on an annual basis since 1980. Results from the 2020 sampling event were added to previous results reported from soil samples collected in 2003 and 2014. The SOC concentrations in the topsoil (0-75 mm depth), ranging from 4.23 to 5.99% across all slopes and aspects of the farmlets, fell within the normal range (≥3.5 and <7.0%) required for sustaining production and environmental goals. A trend was shown for greater SOC stocks in the topsoil in the HF farmlet (34.0 Mg/ ha) compared with the other two farmlets (31.6 Mg/ha), but this trend was not evident in the deeper soil layers (75-150, 150-300, 0-300 mm). Under the current conditions, topographical features such as slope and aspect had a more profound influence on SOC stocks than management history.","PeriodicalId":407057,"journal":{"name":"NZGA: Research and Practice Series","volume":"62 15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134097257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Persistence of the yield advantage of perennial ryegrass cultivars: concept, evidence and implications 多年生黑麦草品种产量优势的持续:概念、证据和意义

NZGA: Research and Practice Series Pub Date : 2021-06-30 DOI: 10.33584/rps.17.2021.3452

D. Chapman, C. Ludemann, W. Griffiths, L. Rossi, D. Waugh, B. Kuhn-Sherlock

{"title":"Persistence of the yield advantage of perennial ryegrass cultivars: concept, evidence and implications","authors":"D. Chapman, C. Ludemann, W. Griffiths, L. Rossi, D. Waugh, B. Kuhn-Sherlock","doi":"10.33584/rps.17.2021.3452","DOIUrl":"https://doi.org/10.33584/rps.17.2021.3452","url":null,"abstract":"Pasture persistence can be defined several ways, but a key outcome for farmers is that the yield advantage of a new pasture compared to the pasture it replaced persists for several years after sowing. The concept of persistence of the yield advantage can also be applied to genetic evaluation of cultivars in species such as perennial ryegrass to determine the true value of pasture renewal and cultivar selection. We analysed 8 years of yield and tiller density data from pastures sown to four perennial ryegrass cultivars representing different functional types at two locations, Waikato (non-irrigated) and Canterbury (irrigated). ‘Grasslands Nui’ SE (Nui) was designated as the baseline cultivar. A significant yield advantage over Nui was observed for two cultivars (Alto AR37 and Halo AR37). Peak yield advantage occurred 4 or 5 years post-sowing, then declined by approximately 50% and became nonsignificant by Year 8. The pattern was very similar at both locations. Tiller density data indicated a shift in sward structure over time consistent with size-density trade-offs in the diploid cultivar Alto AR37 but not in the tetraploid cultivar Halo AR37. The implications for economic evaluation systems such as the DairyNZ Forage Value Index are discussed.","PeriodicalId":407057,"journal":{"name":"NZGA: Research and Practice Series","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125334318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

The role of Epichloë grass endophytes during pasture renewal Epichloë草内生菌在牧草更新中的作用

NZGA: Research and Practice Series Pub Date : 2021-05-07 DOI: 10.33584/RPS.17.2021.3446

K. Hewitt, C. Matthew, C. McKenzie, W. Mace, A. Popay

引用次数: 0

The effects of clover and nitrogen fertiliser on the presence of pasture pests in dairy pastures 三叶草与氮肥对奶牛场牧草害虫的影响

NZGA: Research and Practice Series Pub Date : 2021-05-07 DOI: 10.33584/RPS.17.2021.3448

A. Popay, D. Wilson, C. Ferguson, D. Chapman, Julia M. Lee, G. Cosgrove, D. Stevens

引用次数: 1

Epichloë endophytes – new perspectives on a key ingredient for resilient perennial grass pastures Epichloë内生菌-对有弹性的多年生牧草的关键成分的新观点

NZGA: Research and Practice Series Pub Date : 2021-05-07 DOI: 10.33584/RPS.17.2021.3435

J. Caradus, D. Chapman, T. Cookson, Blair Cotching, M. Deighton, L. Donnelly, J. Ferguson, S. Finch, Sarah Gard, D. Hume, L. Johnson, G. Kerr, M. Norriss, Kate Peddie, A. Popay

引用次数: 10

Yield and botanical composition of four dryland pastures at Ashley Dene Research Farm over 8 years 8年来Ashley Dene研究农场四个旱地牧场的产量和植物组成

NZGA: Research and Practice Series Pub Date : 2021-05-07 DOI: 10.33584/RPS.17.2021.3445

Breanna Taylor, A. Mills, Malcolm C. Smith, R. Lucas, D. Moot

{"title":"Yield and botanical composition of four dryland pastures at Ashley Dene Research Farm over 8 years","authors":"Breanna Taylor, A. Mills, Malcolm C. Smith, R. Lucas, D. Moot","doi":"10.33584/RPS.17.2021.3445","DOIUrl":"https://doi.org/10.33584/RPS.17.2021.3445","url":null,"abstract":"Dry matter yield and botanical composition of four grazed dryland pasture types were compared over 8 years in summer-dry conditions at Ashley Dene, Canterbury, New Zealand. The experiment was sown in March 2013 to evaluate cocksfoot (CF)- or meadow fescue/ryegrass hybrid (RG)-based pastures established with either subterranean (Sub) or subterranean and balansa (S+B) clovers. Plantain was included in all pasture types. Perennial ryegrass established poorly on the low soil moisture holding capacity Lismore soil and in Year 2 was re-broadcast into the RG pastures. Despite this, plantain was the main sown species in RG pastures beyond Year 3. Total spring yield was greatest in Year 5 at 6720 kg DM/ha and varied with spring rainfall. Cocksfoot-based pastures had 60% of sown species present in the spring of Year 8, compared with 28% in RG-based pastures. Balansa clover was only present up to Year 5 after a managed seeding event in the first spring. White clover did not persist in the dryland environment past Year 2. Sub clover yield depended on the time and amount of autumn rainfall but contributed up to 45% of the spring yield. Cocksfoot-sub clover pastures appear to be most resilient in this summer-dry environment with variable spring rainfall.","PeriodicalId":407057,"journal":{"name":"NZGA: Research and Practice Series","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129324674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Resident hill country pasture production in response to temperature and soil moisture over 20 years in Central Hawke’s Bay 中霍克斯湾20年来对温度和土壤湿度的响应

NZGA: Research and Practice Series Pub Date : 2021-05-07 DOI: 10.33584/rps.17.2021.3451

A. Mills, B. Thomson, Paul Muir, Noel Smith, D. Moot

{"title":"Resident hill country pasture production in response to temperature and soil moisture over 20 years in Central Hawke’s Bay","authors":"A. Mills, B. Thomson, Paul Muir, Noel Smith, D. Moot","doi":"10.33584/rps.17.2021.3451","DOIUrl":"https://doi.org/10.33584/rps.17.2021.3451","url":null,"abstract":"The production of resident pastures on rolling hill country was measured in three paddocks over 20 years at Poukawa in Central Hawke’s Bay. The pastures had been routinely fertilised with 250 kg/ha/yr of superphosphate but no pasture renovation, nor nitrogen fertiliser application, occurred during the measurement period. Total annual dry matter (DM) yield ranged from 4.5 to 12.8 t/ha/yr, which shows the level of variability to be expected in this summer-dry environment. The greatest proportion (60-90%) of growth occurred in winter/spring with consistent mean growth rates of 50-62 kg DM/ha/d in September and October. These rates were calculated to be 5.49±0.55 kg DM/ha/°Cd when spring moisture was non-limiting. The pastures had a mean water use efficiency of 16.9±0.34 kg DM/ha/mm of water available (R2 = 0.93). The amount of water available was calculated from a soil water budget based on a plant available water holding capacity of 124 mm (0-1.0 m depth). The results provide coefficients that can be combined with readily available climate data to predict pasture growth rates for feed budgeting purposes. Rainfall data collected on-site was highly correlated (r=0.94) with that predicted from the NIWA virtual climate station network.","PeriodicalId":407057,"journal":{"name":"NZGA: Research and Practice Series","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114241783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Using new insights in grazing management to buffer the impacts of climatic variability on pasture resilience 利用放牧管理的新见解来缓冲气候变化对牧场恢复力的影响

NZGA: Research and Practice Series Pub Date : 2021-05-07 DOI: 10.33584/RPS.17.2021.3439

D. Stevens, C. Matthew, K. Tozer

{"title":"Using new insights in grazing management to buffer the impacts of climatic variability on pasture resilience","authors":"D. Stevens, C. Matthew, K. Tozer","doi":"10.33584/RPS.17.2021.3439","DOIUrl":"https://doi.org/10.33584/RPS.17.2021.3439","url":null,"abstract":"Pasture is the main source of nutrition for the New Zealand ruminant livestock industry. Changing climatic conditions and relentless intensification are putting the ability of pastures to provide that nutrition under pressure. Recent understanding of the interactions between grazing management and the life cycle of roots, leaves and seedheads of pasture species creates further opportunities to increase pasture resilience. Root production is directly related to, though lagging, leaf production and turnover. Tiller production is modified by temperature and seedhead production. Matching grazing patterns to maximise the production of each of these features is generally impossible at the farm scale. However, matching some of these characteristics on some of the farm can be achievable, and have long-lasting benefits for pasture resilience. Therefore, grazing management practices such as deferred grazing in late spring, summer and autumn may be used both to provide a boost to root and tiller production, and to transfer feed from one grazing period to another. Changing our winter management practices away from intensive daily allocations towards 4-day shifting may also increase early spring production, while reducing summer grazing pressure in droughts will aid pasture productivity and persistence in the long term. These techniques have the potential to ensure that the future nutritional needs of grazing ruminants will continue to be met by grazed pasture.","PeriodicalId":407057,"journal":{"name":"NZGA: Research and Practice Series","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117331268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of deferred grazing on profitability of a hill country farm in north-western Waikato 推迟放牧对怀卡托西北部山区农场盈利能力的影响

NZGA: Research and Practice Series Pub Date : 2021-05-07 DOI: 10.33584/RPS.17.2021.3442

K. Tozer, S. Howarth, J. Sherlock, I. Tarbotton

引用次数: 3

Resilient pastures and sediment: a case study in Hawke's Bay 弹性牧场和沉积物:霍克湾的案例研究

NZGA: Research and Practice Series Pub Date : 2021-04-21 DOI: 10.33584/RPS.17.2021.3432

D. Read

引用次数: 0