東華大學圖書館 |

Cover Crops and Poultry Integration for Sustainable Soil Management in Organic Vegetable Production.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Cover Crops and Poultry Integration for Sustainable Soil Management in Organic Vegetable Production./
作者:	Bilenky, Moriah.
出版者:	Ann Arbor : ProQuest Dissertations & Theses, : 2021,
面頁冊數:	138 p.
附註:	Source: Dissertations Abstracts International, Volume: 83-04, Section: B.
Contained By:	Dissertations Abstracts International83-04B.
標題:	Horticulture. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=28544671
ISBN:	9798460406111

Cover Crops and Poultry Integration for Sustainable Soil Management in Organic Vegetable Production.
Bilenky, Moriah.

Cover Crops and Poultry Integration for Sustainable Soil Management in Organic Vegetable Production. - Ann Arbor : ProQuest Dissertations & Theses, 2021 - 138 p.

Source: Dissertations Abstracts International, Volume: 83-04, Section: B.

Thesis (Ph.D.)--Iowa State University, 2021.

This item must not be sold to any third party vendors.

Cover cropping and integration of livestock are two of the options that organic vegetable growers can utilize for nutrient management and can improve soil health. Although cover cropping is common in diversified organic farms, summer cover crops and animal integration are less common. Use of summer cover crops prior to fall vegetable production could provide organic vegetable growers additional opportunity to utilize cover crops in their systems while integrating livestock could move organic growers closer to a closed nutrient cycle. Primary goals of the research projects in Chapter 2 and Chapter 3 were to evaluate summer cover crops for weed suppression, nutrient addition, and soil health and to study the effects of integrating poultry into organic vegetable rotations on soil health, vegetable yield and quality, and food safety.While fall-seeded cover crops are most common, summer-seeded cover crops prior to fall vegetable production could provide organic vegetable growers some of the same agroecosystem services. Summer cover crops sown in mid-June and terminated in early August were examined for their impact on weed suppression, fall vegetable yield, soil nutrient status, labile carbon (C), microbial biomass and functional diversity, and plant available nitrate (NO3-N) using anion exchange membranes (AEMs) as compared to a no cover crop control (NC). The cover crops were brown top millet (Panicum ramosum L., BTM), buckwheat (Fagopyrum esculentum Moench, var. Mancan, BW), cowpea (Vigna unguiculata (L). Walp., var. Iron and Clay, CP), flax (Linum usitassimum L. var. Golden, GF), mung bean (Vigna radiata (L.) R. Wilczek , MB), sunnhemp (Crotalaria juncea L., SH), sorghum sudangrass (Sorghum bicolor L. Moench x Sorgum sudanense Piper Staph. var. Sorgrow BMR Dwarf, SS), and Teff grass (Eragrostis tef (Zuccagni) var. Selam, TEF). Cover crop biomass ranged from 1.4 to 6.9 Mg⸱ha-1 with BTM, BW, SH, SS, and TEF producing the largest amount of biomass (6.2, 6.0, 5.0, 6.6, and 6.9 Mg⸱ha-1, respectively) and CP, GF, and MB producing the lowest (1.4, 2.1, and 2.0 Mg⸱ha-1, respectively). Treatments ordered from most weed suppression to lowest (TEF>BTM=BW>SS=SH>CP=GF=MB>NC). TEF reduced weed cover by more than 50% as compared to CP, GF, MB and no-cover crop treatment, respectively. Carbon to nitrogen ratio (C:N) varied based on cover crop type. The range of C:N was (12.6:1-60.7:1) with the legume cover crops (CP, MB, and SH), and GF having the lowest C:N and the grasses (BTM, SS, and TEF) the highest. In 2019, cabbage yield was greater under legume cover crops as compared to NC by 43%, on average. Beet yield and diameter was higher under MB in 2019 by 71.2 and 145.3%, respectively. Yields of cabbage in CP, MB, and SH were on average 45 and 21% higher as compared to the no cover crop control (NC) in 2019 and 2020, respectively. NO3-N adsorbed to AEMs was highest at week four across all treatments. Positive mean effect sizes for MBC as compared to NC was highest for BTM and GF (0.6) while for POXC the mean effect size was highest for CP (0.6) at cover crop termination and GF (1.0) and MB (1.6) post-vegetable harvest. Principal component analysis (PCA) performed on the five principle component loadings of carbon substrates showed MB and TEF were associated with carbohydrates while BW, GF, and SS were associated with polymers. This study shows that there are tradeoffs between cover crops that suppress weeds and those that fix nitrogen. The non-legume, grass cover crops BTM, SS, and TEF can be used to reduce weed pressure in organic vegetable production but have the potential to immobilize nitrogen and reduce yields. Sunnhemp (SH) highly reduce weed pressure (by 94.3%) when compared to NC while also adding N and could be used as a successful summer cover crop planted in monoculture. The other legume cover crops studied, CP and MB provided nitrogen but weed suppression was poor. Growers could consider using CP and MB in a mixture with high biomass producing cover crops to provide weed suppression along with N. Future research should examine how the tradeoffs between N fixation and weed suppression are reduced by the use of summer cover crop mixtures and their impacts on soils and vegetable crops.The integration of animals into vegetable cropping systems is uncommon, but may bring organic growers closer to a closed loop system. To examine the use of animal integration for organic growers, we compared three rotation treatments (two that integrated chickens and a no chicken control): vegetables - cover crop (V-CC, control), vegetables - cover crop - poultry (V-CC-P), and vegetables - poultry - cover crop (V-CC-P). In response to crop rotation we monitored soil nutrient status, soil microbial biomass carbon (MBC), permanganate oxidizable carbon (POXC), and microbial catabolic potential and diversity using Biolog® microplates over three years. Presence or absence of soil pathogens in soil and vegetables were also measured. Integration of chickens affected N budget such that, nitrate was significantly higher after poultry removal but there was not enough residual N in subsequent years to increase yields for spring crops consistently. We observed varying results for soil health indicators. Between summer 2017 and fall 2018, microbial biomass carbon (MBC) increased from 219.75 to 303.23 mg C kg-1 across all treatments. Between the start of the study in 2017 and the end in 2019, phosphorous (P) increased in all plots from 39.7 to 110.9 mg⸱kg-1. Integrating poultry increased MBC by 25%, on average between both treatments across all sampling dates, compared to the no poultry control (P = 0.042). The potential food safety risks of integrating poultry into vegetable production is of concern as E. coli was detected in all plots in the spring of 2019 and select replications of plots in the fall of 2019. Salmonella was found in one plot in 2018. Despite E.coli being detected in treatment plots, no pathogens were detected on the spinach crop when leaf surfaces were tested. Overall our research found that integrating poultry into organic vegetable crop rotations increases nitrate and has potential for off farm fertilizer reductions if time and stocking density are further examined. Soil health may be improved but, MBC and other soil health indicators such as labile C and microbial community structure should be monitored with longer term rotations. There are food safety risks that come with integration of poultry into vegetable production and fields should be treated as if raw manure has been applied. Overall, the research in this dissertation provides researchers and growers with insight into the use and benefits of summer cover cropping as well as a starting point for further investigating the integration of poultry into vegetable crop rotations.

ISBN: 9798460406111Subjects--Topical Terms:

555447
Horticulture.
Subjects--Index Terms:

Cover crops

Cover Crops and Poultry Integration for Sustainable Soil Management in Organic Vegetable Production.
LDR:08006nmm a2200373 4500 001 2342367
005 20220318093124.5
008 241004s2021 ||||||||||||||||| ||eng d
020 $a 9798460406111
035 $a (MiAaPQ)AAI28544671
035 $a AAI28544671
040 $a MiAaPQ $c MiAaPQ
100 1 $a Bilenky, Moriah. $3 3680719
245 1 0 $a Cover Crops and Poultry Integration for Sustainable Soil Management in Organic Vegetable Production.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2021
300 $a 138 p.
500 $a Source: Dissertations Abstracts International, Volume: 83-04, Section: B.
500 $a Advisor: Nair, Ajay.
502 $a Thesis (Ph.D.)--Iowa State University, 2021.
506 $a This item must not be sold to any third party vendors.
520 $a Cover cropping and integration of livestock are two of the options that organic vegetable growers can utilize for nutrient management and can improve soil health. Although cover cropping is common in diversified organic farms, summer cover crops and animal integration are less common. Use of summer cover crops prior to fall vegetable production could provide organic vegetable growers additional opportunity to utilize cover crops in their systems while integrating livestock could move organic growers closer to a closed nutrient cycle. Primary goals of the research projects in Chapter 2 and Chapter 3 were to evaluate summer cover crops for weed suppression, nutrient addition, and soil health and to study the effects of integrating poultry into organic vegetable rotations on soil health, vegetable yield and quality, and food safety.While fall-seeded cover crops are most common, summer-seeded cover crops prior to fall vegetable production could provide organic vegetable growers some of the same agroecosystem services. Summer cover crops sown in mid-June and terminated in early August were examined for their impact on weed suppression, fall vegetable yield, soil nutrient status, labile carbon (C), microbial biomass and functional diversity, and plant available nitrate (NO3-N) using anion exchange membranes (AEMs) as compared to a no cover crop control (NC). The cover crops were brown top millet (Panicum ramosum L., BTM), buckwheat (Fagopyrum esculentum Moench, var. Mancan, BW), cowpea (Vigna unguiculata (L). Walp., var. Iron and Clay, CP), flax (Linum usitassimum L. var. Golden, GF), mung bean (Vigna radiata (L.) R. Wilczek , MB), sunnhemp (Crotalaria juncea L., SH), sorghum sudangrass (Sorghum bicolor L. Moench x Sorgum sudanense Piper Staph. var. Sorgrow BMR Dwarf, SS), and Teff grass (Eragrostis tef (Zuccagni) var. Selam, TEF). Cover crop biomass ranged from 1.4 to 6.9 Mg⸱ha-1 with BTM, BW, SH, SS, and TEF producing the largest amount of biomass (6.2, 6.0, 5.0, 6.6, and 6.9 Mg⸱ha-1, respectively) and CP, GF, and MB producing the lowest (1.4, 2.1, and 2.0 Mg⸱ha-1, respectively). Treatments ordered from most weed suppression to lowest (TEF>BTM=BW>SS=SH>CP=GF=MB>NC). TEF reduced weed cover by more than 50% as compared to CP, GF, MB and no-cover crop treatment, respectively. Carbon to nitrogen ratio (C:N) varied based on cover crop type. The range of C:N was (12.6:1-60.7:1) with the legume cover crops (CP, MB, and SH), and GF having the lowest C:N and the grasses (BTM, SS, and TEF) the highest. In 2019, cabbage yield was greater under legume cover crops as compared to NC by 43%, on average. Beet yield and diameter was higher under MB in 2019 by 71.2 and 145.3%, respectively. Yields of cabbage in CP, MB, and SH were on average 45 and 21% higher as compared to the no cover crop control (NC) in 2019 and 2020, respectively. NO3-N adsorbed to AEMs was highest at week four across all treatments. Positive mean effect sizes for MBC as compared to NC was highest for BTM and GF (0.6) while for POXC the mean effect size was highest for CP (0.6) at cover crop termination and GF (1.0) and MB (1.6) post-vegetable harvest. Principal component analysis (PCA) performed on the five principle component loadings of carbon substrates showed MB and TEF were associated with carbohydrates while BW, GF, and SS were associated with polymers. This study shows that there are tradeoffs between cover crops that suppress weeds and those that fix nitrogen. The non-legume, grass cover crops BTM, SS, and TEF can be used to reduce weed pressure in organic vegetable production but have the potential to immobilize nitrogen and reduce yields. Sunnhemp (SH) highly reduce weed pressure (by 94.3%) when compared to NC while also adding N and could be used as a successful summer cover crop planted in monoculture. The other legume cover crops studied, CP and MB provided nitrogen but weed suppression was poor. Growers could consider using CP and MB in a mixture with high biomass producing cover crops to provide weed suppression along with N. Future research should examine how the tradeoffs between N fixation and weed suppression are reduced by the use of summer cover crop mixtures and their impacts on soils and vegetable crops.The integration of animals into vegetable cropping systems is uncommon, but may bring organic growers closer to a closed loop system. To examine the use of animal integration for organic growers, we compared three rotation treatments (two that integrated chickens and a no chicken control): vegetables - cover crop (V-CC, control), vegetables - cover crop - poultry (V-CC-P), and vegetables - poultry - cover crop (V-CC-P). In response to crop rotation we monitored soil nutrient status, soil microbial biomass carbon (MBC), permanganate oxidizable carbon (POXC), and microbial catabolic potential and diversity using Biolog® microplates over three years. Presence or absence of soil pathogens in soil and vegetables were also measured. Integration of chickens affected N budget such that, nitrate was significantly higher after poultry removal but there was not enough residual N in subsequent years to increase yields for spring crops consistently. We observed varying results for soil health indicators. Between summer 2017 and fall 2018, microbial biomass carbon (MBC) increased from 219.75 to 303.23 mg C kg-1 across all treatments. Between the start of the study in 2017 and the end in 2019, phosphorous (P) increased in all plots from 39.7 to 110.9 mg⸱kg-1. Integrating poultry increased MBC by 25%, on average between both treatments across all sampling dates, compared to the no poultry control (P = 0.042). The potential food safety risks of integrating poultry into vegetable production is of concern as E. coli was detected in all plots in the spring of 2019 and select replications of plots in the fall of 2019. Salmonella was found in one plot in 2018. Despite E.coli being detected in treatment plots, no pathogens were detected on the spinach crop when leaf surfaces were tested. Overall our research found that integrating poultry into organic vegetable crop rotations increases nitrate and has potential for off farm fertilizer reductions if time and stocking density are further examined. Soil health may be improved but, MBC and other soil health indicators such as labile C and microbial community structure should be monitored with longer term rotations. There are food safety risks that come with integration of poultry into vegetable production and fields should be treated as if raw manure has been applied. Overall, the research in this dissertation provides researchers and growers with insight into the use and benefits of summer cover cropping as well as a starting point for further investigating the integration of poultry into vegetable crop rotations.
590 $a School code: 0097.
650 4 $a Horticulture. $3 555447
650 4 $a Agriculture. $3 518588
650 4 $a Soil sciences. $3 2122699
653 $a Cover crops
653 $a Integrated systems
653 $a Organic
653 $a Soil health
653 $a Vegetable
690 $a 0471
690 $a 0481
690 $a 0473
710 2 $a Iowa State University. $b Horticulture. $3 1671764
773 0 $t Dissertations Abstracts International $g 83-04B.
790 $a 0097
791 $a Ph.D.
792 $a 2021
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=28544671