No description available.

No description available.

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 129-137).

Made available in DSpace on 2014-11-10T11:09:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-25Bitstream added on 2014-11-10T11:58:18Z : No. of bitstreams: 1 000794076.pdf: 2421456 bytes, checksum: 633666a472363ad5b8de1b3e593aea6d (MD5) / O nitrogênio (N) é essencial para a nutrição e a manutenção da coloração verde intensa dos gramados. No entanto, influencia o crescimento da parte aérea e, consequentemente, a frequência de cortes, principal fator do custo de manutenção em gramados. Neste contexto, objetivou-se avaliar a adubação nitrogenada e o uso potencial de herbicidas como reguladores de crescimento em grama esmeralda (Zoysia japonica Steud.), em Argissolo Vermelho, visando manter o gramado com boa qualidade visual (verde intenso) e nutricional bem como reduzir o seu crescimento foliar. O experimento foi conduzido na Fazenda de Ensino, Pesquisa e Extensão da UNESP, Campus de Ilha Solteira/SP, de junho de 2012 a dezembro de 2013. Utilizou-se o delineamento em blocos casualizados com 20 tratamentos dispostos num fatorial 5 x 4 com quatro repetições, sendo quatro herbicidas: glyphosate, imazaquin, imazethapyr e metsulfuron-methyl (aplicados na dose de, respectivamente, 200, 420, 80 e 140 g ha-1 do ingrediente ativo (i. a.)) e a testemunha - sem herbicida; e quatro doses de N na forma de ureia: 0, 5, 10 e 20 g m-2, parceladas em cinco aplicações durante o ano. O gramado foi irrigado por aspersão. Avaliaram-se: as características químicas do solo, o comprimento e a matéria seca das folhas, a área foliar, o índice de clorofila foliar (ICF), a análise por imagem digital e a porcentagem de fitointoxicação da parte aérea, além da concentração e do acúmulo de macro e micronutrientes pelas folhas do gramado. Doses de 10 a 20 g m-2 de N proporcionaram coloração verde intensa e concentração de nutrientes suficiente para a manutenção da grama esmeralda. Os herbicidas metsulfuron-methyl e glyphosate destacaram-se no controle do crescimento do gramado, sendo que o segundo não prejudicou a qualidade estética do mesmo, destacando-se como herbicida que possa ser utilizado como regulador do crescimento de grama esmeralda na dose de 200 g ha-1 do i. a / Nitrogen (N) is essential to nutrition and maintenance intense green color of turfgrasses. However, increases the growth of shoots and, consequently, the frequency of cuts, the main factor in the cost of turfgrasses maintenance. In this context, this study aimed to evaluate the nitrogen fertilization and the potential use of herbicides as growth regulators on zoysiagrass (Zoysia japonica Steud.) on an Ultisol, to maintain the turfgrass with good visual quality and nutrition as well as reduce foliar growth. The research was conducted at the Experimental Station of UNESP, Ilha Solteira/SP from June 2012 to December 2013. It was used a randomized block design with 20 treatments arranged in a factorial scheme 5 x 4 with four replications, being four herbicides: glyphosate, imazaquin, imazethapyr and metsulfuron-methyl (applied at the rate of respectively, 200, 420, 80 and 140 g ha-1 active ingredient (a. i.)) besides a control and four N rates, using urea as a source: 0, 5, 10 and 20 g m- 2 split in five times during the year. The turfgrass was irrigated by sprinkler. Were evaluated: the chemical characteristics of the soil, length and dry matter of leaves, leaf area, ICF index (leaf chlorophyll), the digital image analysis, the percentage of phytotoxicity of the shoot, the concentration and accumulation of macro and micronutrients by the leaves of turfgrass. Nitrogen rates of 10 to 20 g m-2 provided intense green color and sufficient nutrients content to maintain zoysiagrass. The herbicides metsulfuron-methyl and glyphosate stand out in control of the leaf length, the second did not sacrifice esthetic quality of the turfgrass, standing out as herbicide that can be used as a growth regulator of zoysiagrass at the rate of 200 g ha-1 of a. i

Lawn is a homogenized element of modern urban green space. Due to historical and cultural characteristics of Swedish urban planning, lawns are the main common typology in Uppsala (77.3%). Despite the strong attachment of Uppsala people to green carpets, the multibillion lawn industry is highly costly in terms of maintenance and management. It is also a source of pollution due to excessive mowing regime. In this research, social, cultural and regulatory motives behind establishment and management of Uppsala lawns among different stakeholders were researched and discussed through a transdisciplinary approach. In the light of three pillars of sustainability, I had a closer look at management and establishment of lawns in Uppsala municipality and Uppsala’s housing corporation. It was found out that social and recreational aspects of lawns are very much appreciated among all respondents. However, economical and environmental aspects of lawns are barley discussed among planners, managers and politicians and they are under the veil of social values. This research also found out that there is a strong attachment of general public to lawns. It can be explained by lacking of ecological knowledge and environmental understanding about the real role of lawns in urban biodiversity. One of the goals of my research was to find sustainable alternative solutions to the conventional lawns that can be implemented on city and neighbourhood scale as well as to educate public and professionals about importance of lawn’s biodiversity. / LAWN project

No description available.

Master of Science / Department of Biology / David C. Hartnett / A key feature of many grass-dominated ecosystems is the formation of grazing lawns, distinct patches characterized by intense grazing by mammalian herbivores and a dense short-statured grass canopy. A central concept of grazing lawns is the positive feedbacks between grazing animals and the grass resource. Intraspecific morphological plant trait changes and differences in plant species composition could both or individually play a role in the differences in characteristics of grazing lawns and neighboring tallgrass swards. I studied grazing lawns in North American tallgrass prairie to: a) test the ‘architectural shift hypothesis’ where continued grazing leads to changes in plant architecture resulting in more efficient foraging for grazers, creating a positive feedback that increases grazing and b) examine soil resource (nutrient and water) availability and grass nutritive quality on and off lawns to test the nutrient- and water-based pathways for grazing lawn maintenance. In a separate study (not reported here), we a) examined plant community structure on and off lawns to determine whether species composition differences account for the distinct grazing lawn characteristics and b) assessed effects of grazing lawn formation on tallgrass prairie plant species diversity. Several differences in morphological traits between dominant grasses on grazing lawns and tallgrass swards support the architectural shift hypothesis. For Sorghastrum nutans, Dichanthelium oligosanthes, and Pascopyrum smithii, leaf-to-stem ratio was twice as high on grazing lawns compared to surrounding matrix tallgrass vegetation and tiller branching was higher and culm internode lengths were shorter on grazing lawns for these species. However, Andropogon gerardii traits did not differ between grazing lawns and tallgrass vegetation. For all four species, above-ground tiller biomass and number of below-ground buds were both higher on grazing lawns. Overall, these morphological responses resulted in a higher grass canopy density (forage biomass per unit canopy volume) on grazing lawns and this increased grass canopy density in turn results in higher grazer foraging efficiency by increasing the amount of forage intake per bite and per unit time. D. oligosanthes, P. smithii, and S. nutans plants on grazing lawns had a significantly lower carbon-to-nitrogen ratio and higher nitrogen content than plants in the matrix tallgrass vegetation, while A. gerardii showed no significant difference in nitrogen content or in carbon-to-nitrogen ratio between grazing lawns and surrounding matrix tallgrass vegetation. With regards to the total grass canopy (all grass species combined), nitrogen content was significantly higher on grazing lawns compared to tallgrass vegetation for all three field seasons, 2016, 2017, and 2018. All measured soil nutrients, ammonium, nitrate, phosphorus, and sodium, were significantly higher on grazing lawns compared to soils of surrounding tallgrass swards, while water content showed no significant difference between grazing lawns and surrounding tallgrass vegetation. The results of this study strongly indicate that developmental and morphological shifts result in increased forage density and increased grazing efficiency on grazing lawns and that the frequent and intense activities of large grazers result in increased plant nitrogen content and lower C:N ratios in grasses on tallgrass prairie grazing lawns. Thus, at least two different mechanisms, plant architectural shifts and the nutrient-based pathway could both contribute to the positive feedbacks that encourage further grazing on lawns and grazing lawn maintenance on tallgrass prairie.

Orientador: Dagoberto Martins / Banca: Maria Renata Rocha Pereira / Banca: Mario Sergio Tomazela / Banca: Marcelo de Almeida Silva / Banca: Carlos Gilberto Raetano / Resumo: Os gramados podem ser utilizados em diversos ambientes com diferentes propósitos, e possuem características intrínsecas como a espécie de grama utilizada, o nível de manutenção e as técnicas adotadas. O uso de reguladores de crescimento, dentro de um manejo adequado, possibilita uma maior eficiência seja na manutenção ou produção de tapetes de qualidade. Dessa forma, o presente trabalho teve por objetivo avaliar os efeitos de trinexapac-ethyl, piraclostrobina associado ou não ao epoxiconazol e prohexadionecálcio como reguladores vegetais, sobre o crescimento e a qualidade dos tapetes de gramas das espécies Esmeralda (Zoysia japonica Steud.), São Carlos (Axonopus compressus (Sw.) Beauv.) e Bermuda (Cynodon dactylon (L.)). No primeiro estudo, os tratamentos e doses (g i.a. ha-1) testados, com e sem reaplicação foram: trinexapac-ethyl de 113,0 a 226,0, piraclostrobina + epoxiconazol de (66,5+25,0) a (113,0+50), piraclostrobina de 100,0 a 200,0, além de uma testemunha para cada espécie avaliada. No segundo estudo, os tratamentos e doses (g i.a. ha-1) testados, com duas e três reaplicações foram: prohexadione-cálcio de 27,5 a 165,0, além de uma testemunha sem aplicação do regulador de crescimento. Em ambos os estudos, foram realizadas avaliações visuais de fitotoxicidade através de uma escala de notas, na qual, "0" correspondeu a nenhuma injúria demonstrada pelas plantas e "100" a morte das plantas. Também foram avaliados: altura das plantas, número de inflorescências, além da coleta das aparas para determinação da massa seca. Ao final do estudo, os vasos foram desmontados sobre uma peneira e os tapetes foram lavados, bem como o sistema radicular. Em seguida avaliou-se a espessura total do tapete com e sem aparas, comprimento de raiz e posteriormente determinou-se da massa seca deste material. Todos os experimentos foram instalados no delineamento experimental ... / Abstract:The turfgrasses can be used in different environments for different purposes, and possess intrinsic properties such as species of grass used, the level of maintenance and the techniques adopted. The use of plant growth regulators within a proper handling, enables a higher efficiency is the maintenance or production grass sod quality. Thus, this study aimed to evaluate the effects of trinexapac-ethyl, pyraclostrobin associated or not with epoxiconazole and prohexadione-calcium as plant regulators on the growth and quality of species grasses Esmeralda (Zoysia japonica Steud.), São Carlos (Axonopus compressus (SW.) Beauv.) and Bermuda (Cynodon dactylon (L.)). In the first study, the doses and treatments (g a.i. ha-1 ) tested, both with and without reapplication were: trinexapac-ethyl of 113.0 to 226.0, pyraclostrobin + epoxiconazol of (66.5+25.0) to (113.0+50.0), pyraclostrobin of 100.0 to 200.0, in addition to a control for each species evaluated. In the second study, the doses and treatments (g a.i. ha-1 ) tested with two and three reapplication were prohexadione-calcium of 27.5 to 165.0, plus a control without application of growth regulator. In both studies, were performed visual injury evaluations using a scale of notes, in which "0" corresponded to any injury, demonstrated by plants and "100" the death of plants. Were also assessed: plant height, number of inflorescences, in addition to the collection of scrap to determine the dry mass. At the end of the period of conducting the study, the vessels were dismantled on a sieve and rugs were washed away, as well as the root system. Then the total thickness of the mat with and without chips, root length and subsequently was dry mass of this material. All experiments were installed in completely randomized experimental design with four replications. The results were submitted to analysis of variance F-test, and the averages of the treatments were ... / Doutor

Orientador: Dirceu Maximino Fernandes / Coorientador: Caroline de Moura D'Andrea Mateus / Banca: Roberto Lyra Villas Bôas / Banca: Héli Grassi Filho / Banca: Clarice Backes / Banca: Claudinei Paulo de Lima / Resumo: Para que um campo esportivo seja adequado ele precisa ter características desejáveis de qualidade do gramado, permitir o desempenho do atleta, drenagem de água e durabilidade. Dentre as três camadas que formam o campo atlético (sub-base, base e grama), a base é a responsável pelo desenvolvimento radicular da grama e tem influência direta sob os quatro fatores descritos acima. A construção da base dos campos esportivos tem sido baseada nas recomendações da USGA (United States Golf Association) para "greens" de campos de golfe, tendo como principal componente a areia, devido sua alta capacidade de drenagem. Porém, as características desejáveis podem ser variáveis de acordo com a sub base utilizada, que pode alterar propriedades químicas e físicas do solo refletindo na qualidade, desempenho e durabilidade do gramado. O objetivo deste trabalho foi definir a melhor composição da base para os campos esportivos de grama bermuda e gerar informações técnicas que contribuam na construção dos campos de futebol brasileiros. Foram avaliados os seguintes tratamentos: T1: Areia; T2: Areia (80%) + Turfa (20%); T3: Areia (90%) + Solo argiloso (10%); T4: Areia (70%) + Solo arenoso (30%). O delineamento experimental utilizado foi em blocos casualizados, composto por 4 tratamentos e 3 repetições, tendo cada parcela a dimensão de 3 x 4 m. Durante um ano foram realizadas as seguintes avaliações: tração superficial dos gramados, velocidade de infiltração de água na base, resistência mecânica da bas... / Abstract: An appropriate athletic field must have desirable characteristics of quality, performance, durability and drainage. Among the three layers that make up the athletic field (sub-base, base and grass), the base or root zone is responsible for grass root development and has direct influence on the four factors described above. The construction of the root zone of athletic fields has been based on the recommendations of the USGA (United States Golf Association) to greens of golf courses, the main component sand, due to its high drainage capacity, however there may be loss of quality, performance and durability. The objective of this study was define the best composition of the root zone for bermuda grass athletic fields and generate technical information that contribute to the construction of Brazilian soccer fields. We evaluated the following treatments: T1: pure sand, T2: standard USGA (80% sand and 20% peat), T3: pure sand + native clay soil and T4: native sandy soil + pure sand. The experimental design was a randomized block consisting of 4 treatments and 3 replications, each plot size of 6 m x 5 m. During one year were held the following assessments: surface traction, speed of water infiltration into the soil, mechanical strength of the substrate penetration, root depth, substrate humidity, concentration of nutrients in the leaf and chemical analysis of the substrate. The results showed that the exclusive use of sand at the substrate of the composition not show differences over the sand mixtures with peat and soil for the parameters: mechanical strength of the substrate penetration, surface traction ... / Doutor

The rapid pace of urbanization heightens our interest to understand the role of urban areas in mediating climate changes at local, regional and global levels. The increasing amount of carbon (C) released by growing cities may influence the surrounding climates and lead to a rise in global ambient temperature. Fortunately, urban greenery may mitigate the risk of rising C by storing it in vegetation and soils. On the other hand, urban greenery may become a net CO₂ or other greenhouse gas emitter due to heavy maintenances. Thus, the exact impact of urban greenery on carbon balance in major metropolitan areas remains controversial. / We first investigated C footprints of urban turf operation and maintenance by conducting a research questionnaire on different Hong Kong turfs, and showed that turf maintenance contributed 0.17 to 0.63 kg Ce m⁻² y⁻¹ to C emissions. We then determined C sequestration capacity by urban turfgrasses and soils through both field study and laboratory-based investigation. Our data from field study showed that the C stored in turfgrass systems at 0.05 to 0.21 kg C m⁻² for aboveground grass biomass and 1.3 to 4.9 kg C m⁻² for soils (to 15 cm depth). We estimated that the C sink capacity of turfs could be offset by C emissions in 5-24 years under current management patterns, shifting from C sink to C source. / We further showed that dissolved organic C (DOC) export also contributed to C release from urban soils, under the influence of the maintenance practices of turfgrasses. Both irrigation and nitrogen (N) fertilizer inputs could enhance DOC export. We also observed that soil enzyme activity was sensitive to turfgrass maintenances practices, and played a key role in soil organic C (SOC) decomposition. In particular, cellulase was found to be a major player in regulating DOC and dissolved organic N (DON) export. On the other hand, urease activity was shown to be dependent on grass species, fertilizer inputs and substrates. / Finally, we then determined the CO₂ fluxes of turfgrass systems by chamber-based measurement. Our data demonstrated that grass species and photosynthetically active radiation (PAR) played a dominant role in CO₂ fluxes in greenhouse study. Maintenance practices also contributed to CO₂ fluxes of turfgrass systems. Both fertilizer and irrigation showed species-specific effect on CO₂ fluxes. We then showed in field studies that CO₂ fluxes and respiration rates of urban turfs varied with grass species, and were higher in wet season than dry season. / Together, our studies suggested that maintenance practices for urban greenery played a key role in SOC decomposition through regulating DOC export and C cycle associated enzymes, therefore may determine the C balance of urban greenery. Our studies further suggest that we can improve maintenance practices to reduce C footprint and enhance the environmental benefits of urban turfgrass systems. We propose that the environmental impact of turfgrass systems should be optimized by the rational design of maintenance schedules based on C sink and emission principles. / 城市化的快速發展提高了我們研究城市的興趣，具體在其對城區和地域性氣候及其對全球气候变化的調節。城區大量碳排放可能影響周圍氣候進而導致全球環境溫度的上升。城市綠化可以緩解這個危機因為植被和土壤能夠通過存儲碳。但是城市綠化系統的大量維護可能是導致二氧化碳或其他溫室氣體的排放。因此城市綠化對碳平衡的影響仍存在爭議。 / 我們以問卷方式調查了香港不同的草坪，計算了維護過程中的碳足跡。研究表明草坪每年的維護造成了相當於每平米0.17至0.63千克碳排放。我們還結合野外和實驗室分析測定了草坪地上生物量和15厘米深土壤的碳儲存量，每平米分別是0.05至0.21，1.3至4.9千克碳。據此我們估計，按照目前的管理模式，草坪的碳儲存量在5至24年可與維護的碳排放相抵，由碳匯轉變為碳源。 / 我們還發現溶解有機碳的流失也加劇了城市土壤碳釋放同時受草坪維護的影响。灌溉和施加氮肥會促進溶解有機碳的釋放。土壤酶對是草坪維護很敏感，而且對土壤有機有機碳分解起關鍵作用。特別是纖維素酶參與并有效調節了溶解有機碳和溶解有機氮的釋放。另外脲酶的活性受草種，施肥和土壤基質的影響。我們用二氧化碳分析儀测定了草坪的碳通量。溫室研究表明，草種和光合有效輻射對碳通量起主導作用。草坪的維護同樣影響草坪的碳通量，其中施肥和灌溉對不同草種的碳通量有不同程度的影響。野外實驗則發現城市草皮的碳通量和呼吸速率隨草種变化，且雨季高於旱季。 / 以上研究表明城市綠化系統的維護可以有效調節溶解有機碳和碳循環相關土壤酶，進而影響土壤有機碳的分解，最終決定城市綠化系統的碳收支。因此我們建議，由以經驗設計轉變為以碳匯和碳排放原則優化維護模式，以減少碳足跡從而提升城市綠化的環境效益。 / Kong, Ling. / Thesis Ph.D. Chinese University of Hong Kong 2014. / Includes bibliographical references (leaves 191-212). / Abstracts and appendixes also in Chinese. / Title from PDF title page (viewed on 24, October, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.