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Identification of Brush Species and Herbicide Effect Assessment in Southern Texas Using an Unoccupied Aerial System (UAS)
Get PDFCultivation and grazing since the mid-nineteenth century in Texas has caused dramatic changes in grassland vegetation. Among these changes is the encroachment of native and introduced brush species. The distribution and quantity of brush can affect livestock production and water holding capacity of soil. Still, at the same time, brush can improve carbon sequestration and enhance agritourism and real estate value. The accurate identification of brush species and their distribution over large land tracts are important in developing brush management plans which may include herbicide application decisions. Near-real-time imaging and analyses of brush using an Unoccupied Aerial System (UAS) is a powerful tool to achieve such tasks. The use of multispectral imagery collected by a UAS to estimate the efficacy of herbicide treatment on noxious brush has not been evaluated previously. There has been no previous comparison of band combinations and pixel- and object-based methods to determine the best methodology for discrimination and classification of noxious brush species with Random Forest (RF) classification. In this study, two rangelands in southern Texas with encroachment of huisache (Vachellia farnesianna [L.] Wight & Arn.) and honey mesquite (Prosopis glandulosa Torr. var. glandulosa) were studied. Two study sites were flown with an eBee X fixed-wing to collect UAS images with four bands (Green, Red, Red-Edge, and Near-infrared) and ground truth data points pre- and post-herbicide application to study the herbicide effect on brush. Post-herbicide data were collected one year after herbicide application. Pixel-based and object-based RF classifications were used to identify brush in orthomosaic images generated from UAS images. The classification had an overall accuracy in the range 83–96%, and object-based classification had better results than pixel-based classification since object-based classification had the highest overall accuracy in both sites at 96%. The UAS image was useful for assessing herbicide efficacy by calculating canopy change after herbicide treatment. Different effects of herbicides and application rates on brush defoliation were measured by comparing canopy change in herbicide treatment zones. UAS-derived multispectral imagery can be used to identify brush species in rangelands and aid in objectively assessing the herbicide effect on brush encroachment
Biochar and Nitrogen Effects on Soil Microbes in Switchgrass (Panicum virgatum) Soil
No full textSwitchgrass is a warm-season C4 grass inherent to North America; it is a natural constituent of the tallgrass plain that conceals most of the great plains. The aim of the study conducted at Tennessee State University “was to find out biochar and nitrogen fertilization effect attached to the” microbial community in switchgrass soil. A two-factor randomized complete block design, which consist of three levels of nitrogen and biochar rates (0, 80, and 160 kg N·“hm-2) and (0”, 20, and 40 “t·hm-2) respectively” was used. BIOLOG (AWCD), Shannon indexes, microbial abundance by gene sequencing, and N2O emission were determined. The AWCD and Shannon index results showed a gradual increase in the microbial metabolic activities and microbial population at the addition of nitrogen treatment compared to the control. The bacterial genera Nitrosomonas, Rhizobium, Nitrobacter, Nitrospira, and Nostoc, known to be involved in the nitrogen cycle, were also identified. Pseudomonas made up 73% of the samples\u27 entire bacterial population. They are known to potentially participate in the N2O emission process in switchgrass. During the emission, N2O flux was lower on the 7th day and before treatment, while tends to be higher towards the 30th day. This was obviously due to the longer time of treatment. There was a notable effect on the microbial community when both nitrogen fertilizer and biochar was applied in switchgrass soil. The interactive effect between nitrogen and biochar was particularly strong at their high application rates. Therefore, this study\u27s results showed significant effect on the control of switchgrass soil
The financial implications of specialization, diversification, or alternative enterprises on small farms: Evidence from Tennessee
Get PDFIn response to survival challenges, small farms in the United States undertake decisions to minimize downside risk or maximize gross revenue. Using primary survey data of small farms in Tennessee, we examined farmers’ strategic decisions on specialization or other forms of diversification and estimated the impacts of these decisions on farm financial performance. We found that farmer’s age, farmland holdings, use of a smartphone in farm-related activities, and off-farm work significantly influenced these strategic decisions. Our multinomial endogenous switching regression estimates suggested that small farms could attain significantly higher performance, around 45% higher gross farm income and a 30% higher return on assets, by adding alternative on-farm enterprises
Integration of Drone Multispectral Data for Mapping Winter Wheat and Weeds
No full textIn precision agriculture (PA), it is essential to map the canopy cover of winter wheat and associated weeds’ cover to support crop monitoring and variable rate herbicide application. The objective of the study was to investigate the integration of multispectral drone data with Digital Surface Model (DSM) and vegetation indices (VI) for mapping winter wheat, chickweed, and hairy buttercup. 1) To map winter wheat, chickweed, and hairy buttercup using drone multispectral data, and 2) To analyze changes in mapping accuracies of winter wheat, chickweed, and hairy buttercup resulting from the integration of drone multispectral data with VIs and DSM. A Random Forest classifier based on machine learning was used to classify winter wheat, chickweed, and hairy buttercup. We discovered that the overall mapping accuracy of winter wheat and associated weeds\u27 canopy cover improved by 6% when drone multispectral data was integrated with DSM and VIs, compared to drone multispectral data used alone. In addition, when drone data was integrated with DSM and VIs, respectively, the overall mapping accuracy increased by 3% and 0.3%. Improving the mapping of winter wheat, chickweed, and hairy buttercup will improve crop management, yield, and sustainability
Developing Institutions and Inter-Organizational Synergies through Digitalization and Youth Engagement in African Agriculture: The Case of “Africa Goes Digital”
Get PDFAs digitalization increasingly gains attention in the agriculture sector, many African youths are seizing the opportunity provided by digital technologies to engage in agriculture. While prior studies have started examining the intricacies of digitalization in agriculture, they have paid less attention to its implications for fostering institutions and inter-organizational synergies that can support and sustain the businesses of youth enterprises engaging with Africa’s agriculture. Against this backdrop, we undertook a qualitative case study to shed light on the development of a community of practice comprising youth enterprises engaging in agriculture through digitalization. Thus, we studied Africa Goes Digital (AFGD), a consortium of young African enterprises that rely on digital technologies and solutions to provide services to farmers across the African continent. The results showed that: (1) the Technical Centre for Agricultural and Rural Cooperation ACP-EU (CTA) played a pioneering role as a development agency in supporting enterprises with drones and training for agriculture, which led to the formation of AFGD; (2) two prevalent themes characterized the services offered by AFGD members; (3) AFGD brings members under one platform where they leverage WhatsApp for communication and knowledge sharing and Twitter to showcase success stories and form partnerships with each other to execute certain development projects with governments and development agencies; (4) the lack of regulations or the restrictive regulations on the use of drones are still problems that some members face, and the high costs of sensors and related drones are challenges for the members. Building on the results, we discuss the implications of digitalization for supporting African governments in meeting sustainability goals and conclude by describing the theoretical contribution of our study and promising future research directions
A Mixed Methods Investigation of the Impact of the NCAA Presidential Pledge
No full textIn college athletics, there appears to be evidence of misalignment between stated commitments and institutional practices. Though institutions publicly promote equity, diversity, and inclusion (EDI), college athletic departments have failed to create large scale systemic change in the representation and retention of women and people of color. Largely composed of White male leadership, the existing organizational culture cultivates an environment of inequity and exclusion. To address challenges with institutional cultures and to enhance EDI efforts, the National Collegiate Athletic Association (NCAA) adopted initiatives such as the Presidential Pledge and athletic diversity and inclusion designee (ADID). Using espoused theory and theory-in-use as a framework, this study explored the relationship between stated commitments, departmental activities, and structural change to determine the impact of the NCAA Presidential Pledge on EDI efforts in college athletic departments. A mixed methods explanatory sequential design was used to survey NCAA ADIDs. Data for this project were collected through a webbased survey, interviews, and content analysis of institution websites. Most institutions were found to be moderately aligned with the pledge but showed no alignment or minimal alignment in representation of both gender and racial/ethnic minorities. Qualitatively, six themes emerged related to organizational culture, candidate pools, resource allocation, education, recruitment, and accountability. Quantitatively, no significant difference in perspective was found regarding gender or race/ethnicity. It is the hope that this study will inform college athletic leaders of practices that promote or challenge the successful alignment of EDI efforts with stated goals, specifically as it applies to the Presidential Pledge