Grass and Forage Science最新文献_第2页

Shufflenetv2UNet: An improved neural network model for grassland sample coverage extraction Shufflenetv2UNet：用于草原样本覆盖率提取的改进型神经网络模型

IF 2.7 3区农林科学

Grass and Forage Science Pub Date : 2024-11-11 DOI: 10.1111/gfs.12697

Yunyu Liu, Tonghai Liu, Fanzhen Wang, Hongxiao Shi, Hai Wang, Bagen Hasi, Fangyu Gao, Changqin Liu, Hua Li

{"title":"Shufflenetv2UNet: An improved neural network model for grassland sample coverage extraction","authors":"Yunyu Liu, Tonghai Liu, Fanzhen Wang, Hongxiao Shi, Hai Wang, Bagen Hasi, Fangyu Gao, Changqin Liu, Hua Li","doi":"10.1111/gfs.12697","DOIUrl":"https://doi.org/10.1111/gfs.12697","url":null,"abstract":"Accurate extraction of grassland sample coverage is crucial for regional ecological environment monitoring. Due to the strong feature learning capability, high flexibility, and scalability of deep learning methods, they have great potential in grassland sample extraction modelling. However, we still lack a model that can achieve both lightweight structure and effective performance for small object segmentation to considering the small target characteristics of grassland vegetation and the requirements for model deployment in later stages. Here, we combined the UNet model, which performs well in small target segmentation, with the lightweight network Shufflenetv2 model, proposing an improved UNet neural network, Shufflenetv2UNet, for grassland sample coverage extraction. The core of Shufflenetv2UNet is the removal of maximum pooling and double-layer convolution modules from downsampling in the UNet neural network. In addition, the Inverted Residual Block structure module from Shufflenetv2 was added to achieve a lightweight model and improved extraction accuracy. The Shufflenetv2UNet achieves an accuracy of 98.23%, with a parameter size of 50.74 M, and a model inference speed of 0.004 s. Compared to existing extraction methods, this model has advantages in prediction accuracy, parameter size, and model inference speed. Moreover, Shufflenetv2UNet achieved different types of grassland sample coverage extractions, with good robustness, generalization, and universality, enabling investigators to quickly and accurately obtain grassland sample coverage. This allows more dynamic and accurate ground measurement data for regional grassland environmental monitoring.","PeriodicalId":12767,"journal":{"name":"Grass and Forage Science","volume":"79 4","pages":"516-529"},"PeriodicalIF":2.7,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143186906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sustainable intensification of livestock systems using forage legumes in the Anthropocene 在 "人类世 "利用饲用豆科植物可持续地强化畜牧系统

IF 2.7 3区农林科学

Grass and Forage Science Pub Date : 2024-11-11 DOI: 10.1111/gfs.12696

Jose C. B. Dubeux Jr, David M. Jaramillo, Erick R. S. Santos, Liza Garcia, Luana M. D. Queiroz, Igor L. Bretas, Cleber H. L. de Souza, Kevin R. Trumpp

{"title":"Sustainable intensification of livestock systems using forage legumes in the Anthropocene","authors":"Jose C. B. Dubeux Jr, David M. Jaramillo, Erick R. S. Santos, Liza Garcia, Luana M. D. Queiroz, Igor L. Bretas, Cleber H. L. de Souza, Kevin R. Trumpp","doi":"10.1111/gfs.12696","DOIUrl":"https://doi.org/10.1111/gfs.12696","url":null,"abstract":"Sustainable intensification of livestock systems implies greater efficiency in resource utilization resulting in greater output of products and other ecosystem services per unit of resource input. Integrating forage legumes into livestock systems is a viable way to reduce the input of industrial N fertilizer, reducing the use of fossil fuels and helping to mitigate global warming, a major problem during the Anthropocene. Some forage legumes have greater concentrations of secondary compounds, such as condensed tannins, that might reduce the emission of greenhouse gases (GHG) from ruminant eructation and excreta. Furthermore, forage legumes might enhance cattle performance because of greater nutritive value, resulting in greater production per unit of GHG released. Shortening the production cycle and improving cattle reproductive efficiency could have a major impact on reducing the overall carbon footprint of the system. Grazing systems with more diversified plant species are typically more resistant and resilient, adapting to current climate changes during the Anthropocene. Novel technologies might accelerate the development of future grazing systems using forage legumes as a key component. Breeding efforts for the next-generation legumes must focus on adaptation and potential use for mitigation of negative environmental impacts. There are examples of successful integration of forage legumes into livestock systems in different regions of the world, with a major reduction in off-farm inputs and maintaining the system productive. These successful examples could be used to increase adoption and improve the efficiency of current livestock systems.","PeriodicalId":12767,"journal":{"name":"Grass and Forage Science","volume":"79 4","pages":"481-498"},"PeriodicalIF":2.7,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143186897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Herbage biomass predictions from UAV data using a derived digital terrain model and machine learning 利用衍生数字地形模型和机器学习从无人机数据中预测垃圾生物量

IF 2.7 3区农林科学

Grass and Forage Science Pub Date : 2024-09-23 DOI: 10.1111/gfs.12694

Philippe Aebischer, Michael Sutter, Amy Birkinshaw, Madlene Nussbaum, Beat Reidy

{"title":"Herbage biomass predictions from UAV data using a derived digital terrain model and machine learning","authors":"Philippe Aebischer, Michael Sutter, Amy Birkinshaw, Madlene Nussbaum, Beat Reidy","doi":"10.1111/gfs.12694","DOIUrl":"https://doi.org/10.1111/gfs.12694","url":null,"abstract":"More than 70% of Switzerland's agricultural area is covered by grasslands that often exhibit highly diverse species compositions and heterogeneous growth patterns. An essential requirement for efficient and effective pasture management is the regular estimation of herbage biomass. While various methods exist for estimating herbage biomass, they are often time-consuming and may not accurately capture the variability within pastures. This highlights the need for more efficient, accurate estimation techniques. To help improve herbage biomass estimation, we present estiGrass3D+, a Random Forest model. This model predicts pasture biomass using a digital terrain model (DTM) derived from a digital surface model (DSM) for sward height modelling, along with vegetation indices and agronomic variables from UAV images only. The model was successfully evaluated with independent test data from different sites on the Swiss central plateau, including both grazed and mown areas. Model performance on an independent validation dataset achieved a NRMSE of 20.3%, while the training dataset had an NRMSE of 21.5%. These consistent results confirm that estiGrass3D+ is both transferable and applicable to unseen data while maintaining accuracy and reliability across different datasets. The wide applicability of our method demonstrates its practicality for predicting herbage biomass under different pasture management scenarios. Additionally, our method of deriving a DTM directly from a DSM simplifies the measurement of grass sward height by UAVs, eliminating the need for prior ground control point (GCP) marking and subsequent aligning, enhancing the efficiency of herbage biomass estimation.","PeriodicalId":12767,"journal":{"name":"Grass and Forage Science","volume":"79 4","pages":"530-542"},"PeriodicalIF":2.7,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gfs.12694","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143187180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Change in leaf C:N:P stoichiometry and its correlations with soil available nutrients and dry matter yield in common vetch/oat intercropping under N fertilization

IF 2.7 3区农林科学

Grass and Forage Science Pub Date : 2024-09-16 DOI: 10.1111/gfs.12693

Junyu Zhang, Xiaojuan Wu, Le Mu, Kaiqi Su, Huimin Yang

{"title":"Change in leaf C:N:P stoichiometry and its correlations with soil available nutrients and dry matter yield in common vetch/oat intercropping under N fertilization","authors":"Junyu Zhang, Xiaojuan Wu, Le Mu, Kaiqi Su, Huimin Yang","doi":"10.1111/gfs.12693","DOIUrl":"https://doi.org/10.1111/gfs.12693","url":null,"abstract":"C, N, and P concentrations and stoichiometric ratios of the leaf are important for adaptive plant growth and nutrient utilization. However, our knowledge of how these traits change with N fertilization in intercropping systems remains limited. Hence, a 2-year experiment was conducted with four cropping patterns, including two-row common vetch (Vicia sativa L.) intercropping with one-row oat (Avena sativa L.), one-row common vetch intercropping with two-row oat as well as sole oat and common vetch cropping with 0, 50, and 100 kg N/ha fertilization. Leaf total nitrogen (LTN) and phosphorus (LTP) concentrations and C:N:P stoichiometric ratios were measured and their linkages with soil nutrient availability were analysed. N fertilization significantly increased LTN, N:P, and C:P, while significantly decreasing LTP and C:N. Intercropping affected leaf nutrient concentrations and stoichiometric ratios, which were affected by N fertilization, basic soil fertility, and crop species. Intercropping and N fertilization affected soil nitrate nitrogen (SNN), available phosphorus (SAP) content, and dry matter (DM) yield. There were strong correlations between the leaf nutritional traits of oats and SNN, SAP, and DM, but few correlations were observed with common vetch. In conclusion, intercropping led to contrasting changes in leaf nutrient concentrations and stoichiometric ratios, which varied with N fertilization and crop species. We failed to reveal solid and direct effects of intercropping ratio on leaf nutritional traits. These findings contribute to a better understanding of crop nutritional traits and the link between leaves and soil in response to intercropping and N fertilization.","PeriodicalId":12767,"journal":{"name":"Grass and Forage Science","volume":"79 4","pages":"604-618"},"PeriodicalIF":2.7,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143187054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Species dynamics in forage seed mixtures exposed to different lengths of growing season 不同生长期牧草种子混合物的物种动态变化

IF 2.7 3区农林科学

Grass and Forage Science Pub Date : 2024-09-09 DOI: 10.1111/gfs.12692

Ievina Sturite, Tor Lunnan, Liv Østrem

{"title":"Species dynamics in forage seed mixtures exposed to different lengths of growing season","authors":"Ievina Sturite, Tor Lunnan, Liv Østrem","doi":"10.1111/gfs.12692","DOIUrl":"10.1111/gfs.12692","url":null,"abstract":"Six seed mixtures differing in number of species and their proportion of timothy (Phleum pratense L.) were tested during three/four production (ley) years in replicated field experiments at three climatically different sites in Norway; one a mountainous inland site at 61° N (Løken) and two in coastal environments, at 61° N (Fureneset) and 65° N (Tjøtta). There were significant differences in forage accumulation (FA) and digestible forage accumulation (DFA) between the three sites. There was a significant FA decline from the third to the fourth ley year for mixtures containing timothy, but not for mixtures without timothy. Estimated interannual FA- stability was higher for timothy-based seed mixtures than for mixtures without timothy at the inland site, but FA-stability was lower at the coastal sites. In the third-year herbage of timothy-based mixtures at the inland site consisted almost solely of timothy, whereas at the coastal sites meadow fescue (Festuca pratensis Huds.) and especially tall fescue (F. arundinacea Schreb.) dominated. In seed mixtures without timothy, cocksfoot (Dactylis glomerata L.) suppressed other species at the inland site, whereas at the coastal sites, tall fescue and ryegrasses (Lolium spp.) were the dominant species in the third-year herbage. Length of growing season and site-specific growing conditions were important drivers for the observed species changes. Timothy can thus be recommended for ley establishment at sites where the growing season is short (<4 months) and plant growth is intensive, but under conditions with a longer growing season it needs to be sown in mixtures with grass species that surpass the regrowth capacity of timothy.","PeriodicalId":12767,"journal":{"name":"Grass and Forage Science","volume":"79 4","pages":"619-629"},"PeriodicalIF":2.7,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gfs.12692","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Annual and seasonal dry matter production, botanical species composition, and nutritive value of multispecies, permanent pasture, and perennial ryegrass swards managed under grazing 放牧管理的多物种、永久性牧草和多年生黑麦草的年和季节性干物质产量、植物物种组成和营养价值

IF 2.7 3区农林科学

Grass and Forage Science Pub Date : 2024-09-07 DOI: 10.1111/gfs.12691

Jane Shackleton, Tommy M. Boland, Jean Kennedy, Cornelia Grace, Gaspard Beaucarne, Stuart F. Kirwan, Olaf Schmidt, Helen Sheridan

{"title":"Annual and seasonal dry matter production, botanical species composition, and nutritive value of multispecies, permanent pasture, and perennial ryegrass swards managed under grazing","authors":"Jane Shackleton, Tommy M. Boland, Jean Kennedy, Cornelia Grace, Gaspard Beaucarne, Stuart F. Kirwan, Olaf Schmidt, Helen Sheridan","doi":"10.1111/gfs.12691","DOIUrl":"10.1111/gfs.12691","url":null,"abstract":"Reduced reliance on inputs such as fertilizer is fundamental to sustainable grazing systems. This two-year study compared four sward types, including multispecies swards (MSS), for herbage dry matter (DM) production, species contribution to DM, and herbage nutritive value under grazing. The systems were: (1) Lolium perenne L. monoculture (PRG; 170 kg N ha−1 year−1); (2) permanent pasture (PP; 135 kg N ha−1 year−1), (3) six species sward consisting of two grasses, two legumes and two herbs (6S; 70 kg N ha−1 year−1), (4) twelve species sward consisting of three grasses, four legumes and five herbs (12S; 70 kg N ha−1 year−1). Herbage samples were collected for DM yield, botanical composition, and nutritive value. Mean annual DM production for PRG, PP, 6S, and 12S was 11,374, 8526, 13,783, and 13,338 kg DM ha−1 respectively. Herb proportions decreased in 6S and 12S from 2020 to 2021 while grass proportions increased. Mean crude protein levels were similar across all systems (p > 0.05), with higher ash content in 6S and 12S compared to PRG (p < 0.001). Organic matter digestibility was lowest in PP compared to PRG (p < 0.001) while neutral detergent fibre content of PP and PRG were greater than 6S and 12S (p < 0.001). Water soluble carbohydrate content was highest in PRG (p < 0.0001). Over 2 years, MSS delivered increased herbage DM yield and nutritive quality relative to PRG and PP swards, from reduced N inputs. However, maintenance of the herb component of MSS is a challenge.","PeriodicalId":12767,"journal":{"name":"Grass and Forage Science","volume":"79 4","pages":"630-650"},"PeriodicalIF":2.7,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gfs.12691","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Marandu palisade grass-forage peanut mixed pastures: Forage intake, animal behaviour, and canopy structure as affected by grazing intensities 马兰杜垛草-贮藏花生混合牧场：牧草摄入量、动物行为和冠层结构受放牧强度的影响

IF 2.7 3区农林科学

Grass and Forage Science Pub Date : 2024-09-02 DOI: 10.1111/gfs.12688

Priscila Junia Rodrigues da Cruz, Denise Vieira da Silva, Italo Braz Gonçalves de Lima, Gustavo Campos Alves, Bruno Grossi Costa Homem, Bruno Jose Rodrigues Alves, Robert Michael Boddey, Andre Fischer Sbrissia, Daniel Rume Casagrande

{"title":"Marandu palisade grass-forage peanut mixed pastures: Forage intake, animal behaviour, and canopy structure as affected by grazing intensities","authors":"Priscila Junia Rodrigues da Cruz, Denise Vieira da Silva, Italo Braz Gonçalves de Lima, Gustavo Campos Alves, Bruno Grossi Costa Homem, Bruno Jose Rodrigues Alves, Robert Michael Boddey, Andre Fischer Sbrissia, Daniel Rume Casagrande","doi":"10.1111/gfs.12688","DOIUrl":"10.1111/gfs.12688","url":null,"abstract":"Integrating forage legumes into grasslands offers numerous ecosystem services. However, the management of grass-legume pastures is challenging because the interaction between the defoliation frequency and severity may affect the legume persistence and forage intake by grazing animals. This 2-year study evaluated the most effective grazing intensity to increase forage intake while maintaining a balanced legume proportion in tropical pastures consisting of Brachiaria brizantha and Arachis pintoi. Three treatments (grazing intensities) were assessed: severe, moderate, and low, corresponding to stubble heights of 10, 15, and 20 cm, respectively, and a pre-grazing height of 25 cm. Two purebred Tabapua heifers were used for each treatment, and additional put-and-take animals were introduced, as required. Canopy structure, grazing behaviour, nutritive value, and forage intake were evaluated. The legume proportion in herbage mass remained consistent across all intensities, averaging 35% pre- and 32% post-grazing. The grazing duration remained consistent across treatments on the first and third days, with an average grazing time of 390 and 440 min, respectively. Under post-grazing conditions, low-intensity grazing had a 52% greater intake rate than severe-intensity grazing, which was attributed to a greater biting rate (37.9 bites/min) and bite weight (0.9 g DM/bite). Moderate grazing intensity (stubble height of ~15 cm associated with a pre-grazing height of ~25 cm) is recommended to manage a mixture of B. brizantha and A. pintoi when the objective is to couple high forage intake with a balanced legume proportion in the pasture.","PeriodicalId":12767,"journal":{"name":"Grass and Forage Science","volume":"79 4","pages":"666-677"},"PeriodicalIF":2.7,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Does the inclusion of crop and forestry components in forage-based systems affect the ruminal fermentation and methane production of Marandu palisadegrass? 在以饲草为基础的系统中加入农作物和林业成分是否会影响马兰杜棕榈草的瘤胃发酵和甲烷产生？

IF 2.7 3区农林科学

Grass and Forage Science Pub Date : 2024-08-23 DOI: 10.1111/gfs.12690

Alyce Monteiro, Fagner J. Gomes, Solange G. Hoslchuch, Otávio G. Almeida, Bruno C. Pedreira, Adibe L. Abdalla

{"title":"Does the inclusion of crop and forestry components in forage-based systems affect the ruminal fermentation and methane production of Marandu palisadegrass?","authors":"Alyce Monteiro, Fagner J. Gomes, Solange G. Hoslchuch, Otávio G. Almeida, Bruno C. Pedreira, Adibe L. Abdalla","doi":"10.1111/gfs.12690","DOIUrl":"10.1111/gfs.12690","url":null,"abstract":"Understanding how forage can be utilized in the rumen is important for optimizing system efficiency. We aimed to evaluate the ruminal fermentation parameters and methane (CH4) production of Marandu palisadegrass [Brachiaria (syn. Urochloa) brizantha (Hochst. ex A. Rich.) R. D. Webster] growing in monoculture or in integrated systems. The experiment was conducted over 3 years to evaluate four systems [livestock (L), livestock-forestry (LF), crop-livestock (CL), and crop-livestock-forestry (CLF)] during the dry and rainy seasons. In the dry season, palisadegrass in CLF presented the greater crude protein (CP) and the lesser neutral detergent fibre (NDF) concentrations. The greatest gas volume was produced in L, while LF and CL reduced CH4 production compared to L. The greatest ammoniacal-nitrogen concentration, propionate and valeric acid proportions, and degradability of NDF were in CLF. In the rainy season, palisadegrass in LF and CLF presented the greater CP concentration and the lesser CH4 production. Integration of crop and forestry components in a forage-based livestock system affected ruminal fermentation parameters of Marandu palisadegrass, consequently, reducing CH4 production. In addition, the inclusion of a forestry component enhanced forage CP concentration. Integrated systems can improve ruminal fermentation, supporting sustainable livestock production and optimizing forage utilization.","PeriodicalId":12767,"journal":{"name":"Grass and Forage Science","volume":"79 4","pages":"678-688"},"PeriodicalIF":2.7,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Predictive modelling of chlorophyll in Mombaça grass leaves by hyperspectral reflectance data and machine learning 利用高光谱反射数据和机器学习建立蒙巴萨草叶叶绿素预测模型

IF 2.7 3区农林科学

Grass and Forage Science Pub Date : 2024-08-15 DOI: 10.1111/gfs.12689

Miller Ruiz Sánchez, Carlos Augusto Alves Cardoso Silva, José Alexandre Melo Demattê, Fernando Campos Mendonça, Marcelo Andrade da Silva, Thiago Libório Romanelli, Peterson Ricardo Fiorio

{"title":"Predictive modelling of chlorophyll in Mombaça grass leaves by hyperspectral reflectance data and machine learning","authors":"Miller Ruiz Sánchez, Carlos Augusto Alves Cardoso Silva, José Alexandre Melo Demattê, Fernando Campos Mendonça, Marcelo Andrade da Silva, Thiago Libório Romanelli, Peterson Ricardo Fiorio","doi":"10.1111/gfs.12689","DOIUrl":"10.1111/gfs.12689","url":null,"abstract":"Chlorophyll (Chl) concentration is one of the factors that affects crop productivity. This study investigated the prediction of chlorophyll concentrations in Mombaça grass' leaves using hyperspectral data and machine learning techniques. Chlorophyll variations were induced by different levels of nitrogen fertilization (104, 208, 312, and 416 kg ha−1). Spectral signatures (400–2500 nm) and chlorophyll contents of the leaves were obtained in October, November, and December 2017, and January 2018. Models were generated using Partial Least Square Regression (PLSR), Random Forest (RF), and Support Vector Regression (SVR). Two validation techniques were employed: holdout, dividing the data into training (75%) and testing (25%) sets; and leave-one-date-out cross-validation (LOOCV), in which one date was omitted during model training and used to predict the omitted date's value. Chlorophyll concentrations varied according to N doses, with the highest concentrations observed in October and December. In these months, there were greater variations in spectral reflectance in the green and red bands (530–680 nm). December was identified as the ideal period for chlorophyll quantification, for both holdout and LOOCV validation techniques. The SVR technique performed best (R2 = 0.71, RMSE = 0.23 mg g−1, dr = 0.72) compared to RF (R2 = 0.63, RMSE = 0.27 mg g−1, dr = 0.66) and PLSR (R2 = 0.60, RMSE = 0.27 mg g−1, dr = 0.67). Therefore, the prediction of chlorophyll in Mombaça grass using spectroradiometry is promising and applicable across different cultivation periods.","PeriodicalId":12767,"journal":{"name":"Grass and Forage Science","volume":"79 4","pages":"543-556"},"PeriodicalIF":2.7,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Alfalfa-bermudagrass mixtures managed under contrasting harvest strategies in the southeastern US 美国东南部在不同收割策略下管理的紫花苜蓿-红豆草混合物

IF 2.7 3区农林科学

Grass and Forage Science Pub Date : 2024-08-05 DOI: 10.1111/gfs.12687

Justin C. Burt, Lisa L. Baxter, Liliane S. Silva, Carol M. Vasco, Christopher G. Prevatt, M. Kimberly Mullenix, R. Lawton Stewart Jr, Jennifer J. Tucker

{"title":"Alfalfa-bermudagrass mixtures managed under contrasting harvest strategies in the southeastern US","authors":"Justin C. Burt, Lisa L. Baxter, Liliane S. Silva, Carol M. Vasco, Christopher G. Prevatt, M. Kimberly Mullenix, R. Lawton Stewart Jr, Jennifer J. Tucker","doi":"10.1111/gfs.12687","DOIUrl":"10.1111/gfs.12687","url":null,"abstract":"The incorporation of dual-purpose alfalfa (Medicago sativa L.) cultivars into bermudagrass (Cynodon spp.) is a viable option to extend the grazing season in Southern forage systems. However, data are limited on which harvest management strategy (HMS) optimizes the use of alfalfa-bermudagrass (ABG) mixtures in the Southern US. A two-year study evaluated ABG mixtures under three HMS [cut only (CO), graze only (GO), or cut and graze (CG)].in Headland, AL and Tifton, GA. Alfalfa-bermudagrass mixtures utilized in this evaluation were ‘Bulldog 805’ alfalfa that was interseeded into ‘Tifton 85’ bermudagrass. Treatments were evaluated for forage, animal, and total system performance. Herbage accumulation varied by year and location (p < .01), but the number of harvests ultimately determined the total forage produced. Forage allowance was never limiting but did differ among treatments at Tifton, GA (p = .02). The CG HMS allowed for similar daily (p > .06) and liveweight gains (p > .56) on fewer days of grazing as compared to the GO treatments. The greater alfalfa percentage in the CG HMS translated to greater total digestible nutrients (TDN) and crude protein (CP), though not always statistically different. The CO HMS maximized system performance when evaluated for total gain (actual gains + predicted gains). However, the CG management allowed for more production opportunities across the season, thereby reducing economic risk. Future research should focus on evaluating the economic implications of introducing each HMS into ABG systems.","PeriodicalId":12767,"journal":{"name":"Grass and Forage Science","volume":"79 4","pages":"689-702"},"PeriodicalIF":2.7,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gfs.12687","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141942509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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