Relevant bibliographies by topics / Canopy density

Academic literature on the topic 'Canopy density'

Author: Grafiati
Published: 4 June 2021
Last updated: 28 January 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Contents

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Canopy density.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Canopy density"

1

Azadeh, Abdollahnejad, Panagiotidis Dimitrios, and Surový Peter. "Forest canopy density assessment using different approaches – Review." Journal of Forest Science 63, No. 3 (March 28, 2017): 107–16. http://dx.doi.org/10.17221/110/2016-jfs.

Full text
Abstract:
Crown canopy is a significant regulator of forest, affecting microclimate, soil conditions and having an undeniable role in a forest ecosystem. Among the different materials and approaches that have been used for the estimation of crown canopy, satellite based methods are among the most successful methods regarding cost-saving efforts and different kinds of options for measuring the crown canopy. Different types of satellite sensors can result in different outputs due to their various spectral and spatial resolution, even when using the same methodologies. The aim of this review is to assess different remote sensing methods for forest crown canopy density assessment.
APA, Harvard, Vancouver, ISO, and other styles
2

Levy, Amit, Taylor Livingston, Chunxia Wang, Diann Achor, and Tripti Vashisth. "Canopy Density, but Not Bacterial Titers, Predicts Fruit Yield in Huanglongbing-Affected Sweet Orange Trees." Plants 12, no. 2 (January 7, 2023): 290. http://dx.doi.org/10.3390/plants12020290.

Full text
Abstract:
In Florida, almost all citrus trees are affected with Huanglongbing (HLB), caused by Candidatus Liberibacter asiaticus (CLas). We characterized various parameters of HLB-affected sweet orange trees in response to yield-improving nutritional treatment, including canopy volume, canopy density and CLas Ct values, and found that the treatment improved yield and maintained canopy density for over three years, whereas untreated HLB-affected trees declined in canopy density. The nutritional treatment did not affect CLas titer or the tree canopy volume suggesting that canopy density is a better indicator of fruit yield. To further validate the importance of canopy density, we evaluated three independent orchards (different in tree age or variety) to identify the specific traits that are correlated with fruit yields. We found that canopy density and fruit detachment force (FDF), were positively correlated with fruit yields in independent trials. Canopy density accurately distinguished between mild and severe trees in three field trials. High and low producing HLB trees had the same Ct values. Ct values did not always agree with CLas number in the phloem, as visualized by transmission electron microscopy. Our work identifies canopy density as an efficient trait to predict yields of HLB-affected trees and suggests canopy health is more relevant for yields than the CLas population.
APA, Harvard, Vancouver, ISO, and other styles
3

Ashaari, Faisal, Muhammad Kamal, and Dede Dirgahayu. "COMPARISON OF MODEL ACCURACY IN TREE CANOPY DENSITY ESTIMATION USING SINGLE BAND, VEGETATION INDICES AND FOREST CANOPY DENSITY (FCD) BASED ON LANDSAT-8 IMAGERY (CASE STUDY: PEAT SWAMP FOREST IN RIAU PROVINCE)." International Journal of Remote Sensing and Earth Sciences (IJReSES) 15, no. 1 (July 6, 2018): 81. http://dx.doi.org/10.30536/j.ijreses.2018.v15.a2845.

Full text
Abstract:
Identification of a tree canopy density information may use remote sensing data such as Landsat-8 imagery. Remote sensing technology such as digital image processing methods could be used to estimate the tree canopy density. The purpose of this research was to compare the results of accuracy of each method for estimating the tree canopy density and determine the best method for mapping the tree canopy density at the site of research. The methods used in the estimation of the tree canopy density are Single band (green, red, and near-infrared band), vegetation indices (NDVI, SAVI, and MSARVI), and Forest Canopy Density (FCD) model. The test results showed that the accuracy of each method: green 73.66%, red 75.63%, near-infrared 75.26%, NDVI 79.42%, SAVI 82.01%, MSARVI 82.65%, and FCD model 81.27%. Comparison of the accuracy results from the seventh methods indicated that MSARVI is the best method to estimate tree canopy density based on Landsat-8 at the site of research. Estimation tree canopy density with MSARVI method showed that the canopy density at the site of research predominantly 60-70% which spread evenly.
APA, Harvard, Vancouver, ISO, and other styles
4

Paudel, Achyut, Manoj Karkee, Joseph R. Davidson, and Cindy Grimm. "Canopy Density Estimation of Apple Trees." IFAC-PapersOnLine 55, no. 32 (2022): 124–28. http://dx.doi.org/10.1016/j.ifacol.2022.11.126.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Ou, Mingxiong, Tianhang Hu, Mingshuo Hu, Shuai Yang, Weidong Jia, Ming Wang, Li Jiang, Xiaowen Wang, and Xiang Dong. "Experiment of Canopy Leaf Area Density Estimation Method Based on Ultrasonic Echo Signal." Agriculture 12, no. 10 (September 28, 2022): 1569. http://dx.doi.org/10.3390/agriculture12101569.

Full text
Abstract:
Variable-rate spray systems with canopy leaf area density information detection are an important approach to reducing pesticide usage in orchard management. In order to estimate the canopy leaf area density using ultrasonic sensors, this article proposed three parameter model equations based on ultrasonic echo peaks for canopy leaf area density estimation and verified the accuracy of the three parameter model equations using laboratory-simulated canopy and outdoor tree experiments. The orthogonal regression statistics results from the laboratory-simulated canopy experiment indicated that parameter Vc is more suitable for canopy leaf area density estimation compared to parameter Va and Vb when the density ranges from 0.54 to 5.4 m2m−3. The model equation from parameter Vc has minor systematic errors, and the predicted and observed values of parameter Vc have good agreement with the experimental conditions. The laboratory-simulated canopy and outdoor tree canopy leaf area density verification experiments of parameter Vc were carried out, and the results indicated that the absolute value of the mean relative error is 5.37% in the laboratory-simulated canopy and 2.84% in outdoor tree experiments. The maximum absolute value of the relative error is 8.61% in the laboratory-simulated canopy and 14.71% in the outdoor tree experiments, and the minimum absolute value of the relative error is 3.21% in the laboratory-simulated canopy and 0.56% in the outdoor tree experiments. The laboratory-simulated canopy leaf area density verification results showed that the mean relative errors under canopy leaf area density 0.98 and 4.92 m2m−3 conditions are 6.29% and 5.82%, respectively, which is larger than the mean relative error under 2.95 m2m−3; nevertheless, these results proved that this model equation is applicable for canopy information detection and advanced pesticide application development in future.
APA, Harvard, Vancouver, ISO, and other styles
6

Andreu, Anne G., John I. Blake, and Stanley J. Zarnoch. "Estimating canopy fuel characteristics for predicting crown fire potential in common forest types of the Atlantic Coastal Plain, USA." International Journal of Wildland Fire 27, no. 11 (2018): 742. http://dx.doi.org/10.1071/wf18025.

Full text
Abstract:
We computed four stand-level canopy stratum variables important for crown fire modelling – canopy cover, stand height, canopy base height and canopy bulk density – from forest inventory data. We modelled the relationship between the canopy variables and a set of common inventory parameters – site index, stem density, basal area, stand age or stand height – and number of prescribed burns. We used a logistic model to estimate canopy cover, a linear model to estimate the other canopy variables, and the information theoretic approach for model selection. Coefficients of determination across five forest groups were 0.72–0.91 for stand height, 0.36–0.83 for canopy base height, 0.39–0.80 for canopy cover, and 0.63–0.78 for canopy bulk density. We assessed crown fire potential (1) for several sets of environmental conditions in all seasons, and (2) with increasing age, density and number of prescribed burns using our modelled canopy bulk density and canopy base height variables and local weather data to populate the Crown Fire Initiation and Spread model. Results indicated that passive crown fire is possible in any season in Atlantic coastal plain pine stands with heavy surface fuel loads and active crown fire is most probable in infrequently burned, dense stands at low fuel moistures.
APA, Harvard, Vancouver, ISO, and other styles
7

Saito, Waka, Koji Kawamura, and Hiroshi Takeda. "Relative importance of overstory canopy openness and seedling density on crown morphology and growth of Acer nipponicum seedlings." Botany 90, no. 11 (November 2012): 1152–60. http://dx.doi.org/10.1139/b2012-079.

Full text
Abstract:
We investigated the effects of overstory canopy openness and seedling density on seedling morphology and growth in the mid-successional species Acer nipponicum Hara in a cool-temperate forest. Studied seedlings were 46 seedlings of 30–160 cm height, and their overstory canopy openness ranged between 7.2% and 17.0%. Seedling density, measured as the number of conspecific neighboring seedlings within a 50 cm radius of the target seedling, ranged between 0 and 19. There were no significant correlations between seedling height, canopy openness, and seedling density. Multiple regression analysis showed that crown depth, leaf mass fraction, and leaf area index decreased with decreasing canopy openness and increasing seedling density, while the ratio of trunk-lateral branches mass increased. Overstory canopy openness did not affect crown area, leaf size, or petiole length, all of which decreased with increasing seedling density. Standardized regression coefficients indicated that seedling density affected morphology and growth more than canopy openness did. The morphological responses to canopy openness cannot be considered as adaptive plasticity, as total leaf area and leaf mass fraction decreased with decreasing light levels. In contrast, responses to seedling density indicate adaptive responses to neighborhood competition. The results highlight the importance of seedling density that influenced seedling growth and morphology independently of overstory canopy openness.
APA, Harvard, Vancouver, ISO, and other styles
8

Umarhadi, Deha Agus, and Akbar Muammar. "Regression model accuracy comparison on mangrove canopy density mapping." Digital Press Physical Sciences and Engineering 1 (2018): 00001. http://dx.doi.org/10.29037/digitalpress.11249.

Full text
Abstract:
<p class="Abstract">Mangrove canopy density condition is often considered in the coastal environment management, so that the accurate data of spatial distribution of mangrove canopy density is needed. This condition need to be studied further related to methods in the mangrove canopy density mapping. However, did not much research compare the mapping accuracy about mangrove canopy density using vegetation index and the combination of statistical regression models, especially using Sentinel-2A satellite imagery. The purpose of this study is to compare the accuracy of mangrove canopy density mapping using NDVI, MSAVI, and MSARVI with simple linear, quadratic, logarithmic, and exponential regression applied to Sentinel-2A satellite imagery. Mangrove canopy density data resulted from a field survey at Jor and Kecebing Bay, East Lombok. The result of accuracy analysis presented NDVI was the best vegetation index in mapping compared MSAVI and MSARVI with an accuracy above 80 % (linear regression analysis of NDVI: 81.66 %, quadratic regression analysis of NDVI: 80.84 %, exponential regression analysis of NDVI: 80.71 %, logarithmic regression analysis of NDVI: 80.68 %). Mapping the mangrove canopy density through the combination of another vegetation index (MSAVI and MSARVI) with four regression models had accuracy of between 70 % to 80 %, except a mangrove canopy density mapping accuracy using quadratic regression between MSARVI and field data, only reached 62.78 %. <o:p></o:p></p>
APA, Harvard, Vancouver, ISO, and other styles
9

Flukes, EB, CR Johnson, and JT Wright. "Thinning of kelp canopy modifies understory assemblages: the importance of canopy density." Marine Ecology Progress Series 514 (November 6, 2014): 57–70. http://dx.doi.org/10.3354/meps10964.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Sembiring, S. S. B., R. Hermawan, and S. B. Rushayati. "The concentration of CO2 on two canopy densities in Taman Kota 1 Bumi Serpong Damai, South Tangerang." IOP Conference Series: Earth and Environmental Science 918, no. 1 (November 1, 2021): 012008. http://dx.doi.org/10.1088/1755-1315/918/1/012008.

Full text
Abstract:
Abstract Global warming occurs because many greenhouse gases (GHG) retain heat from the earth, which causes the earth’s surface temperature to increase. The GHG contributing most to global warming is carbon dioxide (CO2) due to its highest atmosphere concentration and long life span. The increasing CO2 concentrations in urban areas are caused by transportation and industrial activities. City parks with high tree densities are the potential to reduce CO2 concentration. However, studies related to tree canopy density in reducing CO2 concentrations have not been widely carried out. This study aims to determine the CO2 concentration on two different canopy densities. This research was conducted in March - April 2021 in Taman Kota 1 BSD. Primary data collection was carried out by three replicates based on time as follows: 06.00 am, 01.00 pm, and 05.00 pm at low canopy density and high canopy density locations, respectively, by using the AZ 7725 Carbon dioxide meter tool. The low canopy density had a leaf area index (LAI) of 1.039, whereas the high canopy density had an LAI of 1.409. The highest CO2 concentration is 582.43 ppm in the high canopy density in the morning, while the lowest is 463.16 ppm occurred at the low canopy density in the afternoon. In the morning, CO2 from respiration is still concentrated under the dense canopy because there is less wind to disperse. In the afternoon, the wind speed is higher so that CO2 is more easily distributed.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Canopy density"

1

Yazbeck, Theresia. "THE EFFECTS OF CANOPY DENSITY AND SPACING IN MODULATING POLLUTION DEPOSITION RATE." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1563810652136029.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Lee, Alex C., and alexanderlee@aapt net au. "Utilising airborne scanning laser (LiDAR) to improve the assessment of Australian native forest structure." The Australian National University. Fenner School of Environment and Society, 2008. http://thesis.anu.edu.au./public/adt-ANU20090127.222600.

Full text
Abstract:
Enhanced understanding of forest stocks and dynamics can be gained through improved forest measurement, which is required to assist with sustainable forest management decisions, meet Australian and international reporting needs, and improve research efforts to better respond to a changing climate. Integrated sampling schemes that utilise a multi-scale approach, with a range of data sourced from both field and remote sensing, have been identified as a way to generate the required forest information. Given the multi-scale approach proposed by these schemes, it is important to understand how scale potentially affects the interpretation and reporting of forest from a range of data. ¶ To provide improved forest assessment at a range of scales, this research has developed a strategy for facilitating tree and stand level retrieval of structural attributes within an integrated multi-scale analysis framework. The research investigated the use of fine-scale (~1m) airborne Light Detection and Ranging (LiDAR) data (1,125 ha in central Queensland, and 60,000 ha in NE Victoria) to calibrate other remotely sensed data at the two study sites. The strategy refines forest structure mapping through three-dimensional (3D) modelling combined with empirical relationships, allowing improved estimation of maximum and predominant height, as well as foliage and crown cover at multiple scales. Tree stems (including those in the sub-canopy) were located using a height scaled crown openness index (HSCOI), which integrated the 3D density of canopy elements within the vertical profile into a two-dimensional spatial layer. The HSCOI modelling also facilitated the reconstruction of the 3D distribution of foliage and branches (of varying size and orientation) within the forest volume. ¶ Comparisons between forests at the Queensland and NE Victorian study sites indicated that accurate and consistent retrieval of cover and height metrics could be achieved at multiple scales, with the algorithms applicable for semi-automated use in other forests with similar structure. This information has facilitated interpretation and evaluation of Landsat imagery and ICESat satellite laser data for forest height and canopy cover retrieval. The development of a forest cover translation matrix allows a range of data and metrics to be compared at the plot scale, and has initiated the development of continuous transfer functions between the metrics and datasets. These data have been used subsequently to support interpretation of SAR data, by providing valuable input to 2D and 3D radar simulation models. Scale effects have been identified as being significant enough to influence national forest class reporting in more heterogeneous forests, thus allowing the most appropriate use and integration of remote sensed data at a range of scales. An empirically based forest minimum mapping area of 1 ha for reporting is suggested. The research has concluded that LiDAR can provide calibration information just as detailed and possibly more accurately than field measurements for many required forest attributes. Therefore the use of LiDAR data offers a unique opportunity to bridge the gap between accurate field plot structural information and stand to landscape scale sampling, to provide enhanced forest assessment in Australia.
APA, Harvard, Vancouver, ISO, and other styles
3

Whaley, Joanna. "The physiological response of winter wheat varieties to reductions in plant population density." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368249.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Rist, Stephen G. "The effects of canopy density and vegetative competition on oak seedling numbers in southeastern Ohio." Connect to resource, 2006. http://hdl.handle.net/1811/21759.

Full text
Abstract:
Thesis (Honors)--Ohio State University, 2006.
Title from first page of PDF file. Document formatted into pages: contains 19 p.; also includes graphics. Includes bibliographical references (p. 18-19). Available online via Ohio State University's Knowledge Bank.
APA, Harvard, Vancouver, ISO, and other styles
5

Thomson, C. C. "Rootstock and canopy density effects on grape berry composition : organic acid composition, potassium content and pH." Lincoln University, 2006. http://hdl.handle.net/10182/772.

Full text
Abstract:
The influence of rootstock and canopy density on grape berry composition was investigated over the summer of 2003-2004 on a commercial vineyard at Waipara, North Canterbury. This experiment was designed to investigate the influence of rootstock and canopy density on the acid composition, potassium (K) content and final pH of harvested fruit (Pinot Noir AM 10/5 Lincoln Selection). The trial block consisted of eight rootstocks laid out to an 8 x 8 latin square, each plot consisting of five vines of the same rootstock. Two canopy treatments were overlaid the block (down whole rows, assigned randomly, four rows to each treatment); one treatment allowed to grow naturally, in the other treatment the canopy was thinned removing double burst shoots and laterals. The bunch numbers were adjusted in the Unthinned canopy treatment (UCT) to match the Thinned canopy treatment (TCT). Information was gathered to assess: the canopy size and density (Pinot Quadrat Leaf Layer and Percent Gaps and canopy porosity), the plant yield (and berry size, berries per cluster, cluster weight, clusters per plant), plant K levels at flowering and veraison (from petioles and leaf blades) and berry composition at harvest (soluble solids (as brix), K, titratable acidity (TA), tartaric acid concentration, malic acid concentration and pH). The trial area was non-irrigated on clay loam soils and viticultural management was to best commercial practice. It was found that although rootstock influenced the levels of K in the plant and in the juice at harvest, the level of K in the juice did not influence pH in this experiment (range of rootstock juice K: 808 ppm to 928 ppm, l.s.d. = 75 ppm). The level of tartaric acid concentration in the juice was found to be the dominant influence on the level of pH in this experiment (rootstock pH range: 3.21 to 3.39, l.s.d. = 0.05). The juice concentration of tartaric acid was influenced by both rootstock (rootstock range 4.0 to 4.7 g/L, l.s.d = 0.4) and canopy density (UCT = 4.1, TCT = 4.7, l.s.d. = 0.4), decreased shading positively increasing the level of tartaric acid. The malic acid concentration in the juice was positively influenced by increasing canopy density (UCT = 4.7 g/L, TCT = 4.1 g/L, l.s.d = 0.4) and this played a minor role in the determination of pH in this experiment; an influence of rootstock on the level of malic acid concentration was found. The malic acid concentration strongly influenced the determination of TA (UCT = 11.0 g/L, TCT = 10.2 g/L, l.s.d = 0.5); tartaric acid concentration had a minor influence on the recorded TA. Attempts to characterise the influence of rootstock on malic acid, tartaric acid and pH were inconclusive. Rootstock was found to influence the canopy variables measured in this experiment and the recorded average plant yield. Crosses of Vitis rupestris were found to exhibit the most canopy vigour and those derived from Vitis berlandieri and Vitis riparia the least. The Canopy treatment did not show an influence over yield but the rootstock was found to influence plant yield, through the numbers of berries set in a cluster and the final harvest cluster weight. The influence of rootstock on pH may be described by the influence it exerts on canopy growth and yield but this was thought unlikely. Further research is required to describe the nature of the rootstock influence on K, malic acid, tartaric acid and pH.
APA, Harvard, Vancouver, ISO, and other styles
6

Crifo, Camilla. "VARIATIONS IN ANGIOSPERM LEAF VEIN DENSITY HAVE IMPLICATIONS FOR INTERPRETING LIFE FORM IN THE FOSSIL RECORD." Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1375987428.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Silva, Liliane Severino da. "Tiller population density and demography dynamics of Convert HD 364 brachiariagrass in response to canopy height and growth rate under continuous stocking." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-13112015-110013/.

Full text
Abstract:
Pasture-based livestock production is one of the major economic activities in Brazil. In general, the adoption of new forage materials by producers happens before enough information about their characteristics is generated, compromising their use in commercial systems. An experiment was conducted in Piracicaba, Brazil (22º42\' S, 47º30\' W, 580 m asl.), during two summer growing seasons, with the objective to describe and explain the tillering dynamics of the hybrid brachiariagrass Convert HD 364 (Brachiaria hybrid CIAT 36087) under continuous stocking and variable stocking rate. Responses studied were tiller population density (TPD), tillering demography (appearance rate-TAR - and survival rate- TSR), stability index (SI), average tiller weight (ATW), forage mass (FM), leaf area index (LAI), light interception (LI), mean leaf angle (MLA), stem apex height (hapex) and collar height of the youngest fully expanded leaf (hleaf). The experimental design was a randomized complete block with a factorial arrangement including all possible combinations between three sward heights (10, 25 and 40 cm) and growth rates (50 and 250 kg N ha-1 year-1), with three replications. The data were analyzed using the Mixed Models procedure of SAS and means compared using \"t\" test (P<=0.05). At 10 cm canopy height, Convert HD 364 had TPD 10 and 25% greater than at 25 and 40 cm, respectively. High growth rate resulted in 10% greater TPD and 9% lesser AWT. The 40-cm canopy resulted in ATW 80 and 274% greater than those at 25 and 10 cm, respectively. Under low and high growth rate, respectively, FM of 40-cm canopies was 163 and 41% greater than those of 10- -cm swards. Both, hapex and hleaf, responded similarly to treatments and were greater in taller canopies. Except for the 25-cm canopies there was no difference between growth rates in these responses. At greater growth rate TAR was 29% greater, whereas TSR 13% lesser. TAR and TSR varied along the experimental period, suggesting that they are affected by environmental factors. At the lower growth rate, there was no variation in SI along the experimental period, whereas at the high growth rate SI in February was 20 and 35% greater than in January and March, respectively. The determination of meristem location is an important tool to adequate planning of management strategies in animal production system under grazing.
A pecuária baseada em pastagens é uma das principais atividades econômicas do Brasil. Geralmente, ocorre adoção de novos materiais forrageiros sem que haja informações suficientes sobre suas características produtivas o que compromete seu potencial de uso. Um experimento foi conduzido em Piracicaba (22º42\' S, 47º30\' W, 580 m asl.) durante dois verões agrostológicos tendo por objetivo descrever e explicar a dinâmica de perfilhamento da Brachiaria híbrida Convert HD 364 (Brachiaria hybrid CIAT 36087) sob lotação contínua e taxa de lotação variável. Foram avaliados densidade populacional de perfilhos (DPP), demografia do perfilhamento (taxas de aparecimento - TAP- e sobrevivência de perfilhos - TSP), índice de estabilidade da população de perfilhos (IE), peso médio de perfilhos (PMP), massa de forragem (MF), índice de área foliar (IAF), interceptação luminosa (IL), ângulo de inserção da lâmina foliar (ALF), altura do meristema apical (AMA) e da lígula da última folha expandida (AFE). O delineamento experimental foi em blocos completos casualizados, com arranjo fatorial 3x2, correspondendo às combinações entre alturas de dossel (10, 25 e 40 cm) e taxas de crescimento (50 e 250 kg N ha-1 ano-1), com três repetições. Os dados foram analisados utilizando-se o procedimento de modelos mistos e as médias comparadas utilizando-se o teste \"t\" (P<=0,05). Sob altura de dossel de 10 cm, o capim Convert HD 364 apresentou DPP 10 e 25% superiores àquelas sob 25 e 40 cm, respectivamente. O aumento na taxa de crescimento resultou em aumento de 10% na DPP e decréscimo de 9% no PMP. O PMP foi 80 e 274% maior nos dosséis de 40 cm de altura do que nos de 25 e 10 cm, respectivamente. Dosséis mantidos a 40 cm submetidos à taxa de crescimento baixa e alta, respectivamente, apresentaram incremento de 163 e 233 % na MF do que dosséis de 10 cm. Obtiveram-se respostas similares entre AMA e AFE, nas quais houve um incremento na altura de ambas com o aumento da altura do dossel. Houve diferença entre as taxas de crescimento para AMA e AFE somente em dosséis de 25 cm. Com o aumento da dose de nitrogênio, TAP sofreu aumento de 29%, enquanto, TSP sofreu decréscimo de 13%. TAP e TSP variaram ao longo do período estudado, demonstrando a influência de fatores ambientais nas mesmas. Não houve variação no IE ao longo do período experimental em dosséis sob taxa de crescimento baixa, enquanto na taxa alta o IE foi 20 e 35% maior em Fevereiro do que em Janeiro e Março, respectivamente, para ambos os anos. A determinação da localização do meristema apical é uma importante ferramenta para o planejamento adequado de estratégias de manejo em sistemas de produção animal sob pastejo.
APA, Harvard, Vancouver, ISO, and other styles
8

Okeyo, James Ajuoga. "Effects of topping, stem density, and stage of vine cutting on canopy growth and tuber yield yield of potato (Solanum tuberosum L.)." Diss., Virginia Tech, 1995. http://hdl.handle.net/10919/39156.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Veatch, William Curtis. "Quantifying the Effects of Forest Canopy Cover on Net Snow Accumulation at a Continental, Mid-Latitude Site, Valles Caldera National Preserve, NM, USA." Thesis, The University of Arizona, 2008. http://hdl.handle.net/10150/193352.

Full text
Abstract:
Although forest properties are known to influence snowpack accumulation and spring runoff, the processes underlying the impacts of forest canopy cover on the input of snowmelt to the catchment remain poorly characterized. In this study I show that throughfall and canopy shading can combine to result in maximal snowpacks in forests of moderate canopy density. Snow depth and density data taken shortly before spring melt in the Jemez Mountains of New Mexico show strong correlation between forest canopy density and snow water equivalent, with maximal snow accumulation in forests with density between 25 and 45%. Forest edges are also shown to be highly influential on local snow depth variability, with shaded open areas holding significantly deeper snow than either unshaded open or deep forest areas. These results are broadly applicable in improving estimates of water resource availability, predicting the ecohydrological implications of vegetation change, and informing integrated water resources management.
APA, Harvard, Vancouver, ISO, and other styles
10

Sarver, Jason. "INFLUENCE OF VARIOUS PLANT POPULATIONS ON WEED REMOVAL TIMING IN GLYPHOSATE-RESISTANT SOYBEAN." UKnowledge, 2009. http://uknowledge.uky.edu/gradschool_theses/591.

Full text
Abstract:
Reduced plant population in glyphosate-resistant soybean [Glycine max (L) Merr.] may influence the critical time of herbicide application. Field studies were conducted in 2007 and 2008 at two locations in Kentucky to determine the effect of four weed control programs on soybean seed yield, seed quality, crop canopy, and weed pressure when planted at three densities - 185,000, 309,000, and 432,000 plants ha-1. Plots were treated with glyphosate at either 3 weeks after planting (WAP), 5 WAP, 7 WAP, 3 & 7 WAP, representing common weed control protocols within the state. No differences in seed yield were discovered between plant densities in two of four siteyears. 254,500 plants ha-1 was sufficient for maximum yields in all site-years and was also sufficient to achieve maximum canopy amongst those populations tested in the study. Sequential applications at 3 and 7 WAP provided the highest seed yield, while the 5 WAP and 7 WAP application timings were generally the single applications that allowed for the highest yield and canopy closure, along with the highest visual estimate of weeds controlled. Plant density did not influence the critical period for weed control.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Canopy density"

1

Frazer, G. W. A method for estimating canopy openness, effective leaf area index, and photosynthetically active photon flux density using hemispherical photography and computerized image analysis techniques. Victoria, B.C: Pacific Forestry Centre, 1997.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Kjellmark, Eric Wade. Density and biomass allocation in relation to canopy gap dynamics in four temperate deciduous forest herbs. 1987.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Hawksworth, F. G. Vertical spread of dwarf mistletoe in thinned ponderosa pine in Arizona. 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Cushman, Samuel A., and Tzeidle N. Wasserman. Quantifying loss and degradation of former American marten habitat due to the impacts of forestry operations and associated road networks in northern Idaho, USA. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198759805.003.0012.

Full text
Abstract:
American marten are associated with extensive and unfragmented late seral forest habitats, and are often considered to be particularly vulnerable to habitat loss and fragmentation. This chapter evaluates the impact of road building and timber harvest on habitat suitability for marten in northern Idaho, USA, using an empirically derived, multi-scale habitat suitability model, reconstructing key predictor variables (elevation, forest type, road density, canopy cover, landscape fragmentation and the extensiveness of late seral forest in the landscape) as they appear to have existed prior to harvest, and applying the model to both current and pre-harvest conditions. Calculating changes in the extent and pattern of habitat in the landscape indicate that timber harvest and road construction together reduced marten habitat quality considerably across the study area, which is likely responsible for current patterns of reduced detection rates and lower genetic diversity in areas that have experienced the largest amounts of habitat loss.
APA, Harvard, Vancouver, ISO, and other styles
5

Lopez, Jeremy. Dumb show. Edited by Henry S. Turner. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199641352.013.15.

Full text
Abstract:
This chapter examines the theatrical experience provided by early modern dumb shows and the critical tradition that has emerged around them. It argues that dumb shows are a threshold between drama and theatricality, and that they vividly represent not only the contest between text and performance for authority over theatrical meaning, but also the tendency of each to displace this authority onto the other. In the canon of early modern theatre and in the modern critical tradition, dumb shows are often a sign of a derivative theatricality directed at a merely popular audience. In the dumb show, there is an especially complex and self-conscious encounter between word and action, diegesis and mimesis, presentational vehicles and represented fiction. As a moment of extraordinary semiotic density and redundancy, the dumb show was at once too readerly for the stage and too spectacular for the printed book. The chapter also considers ‘Hamlet’s advice to the players’ and its implications for approaches and responses to the dumb show.
APA, Harvard, Vancouver, ISO, and other styles
6

St. Clair, Robert. Poetry, Politics, and the Body in Rimbaud. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198826583.001.0001.

Full text
Abstract:
Bodies abound in Rimbaud’s poetry in a way that is nearly unprecedented in the nineteenth-century poetic canon: lazy, creative, rule-breaking bodies, queer bodies, marginalized and impoverished bodies, revolting and revolutionary, historical bodies. The question that this book seeks to answer is: what does this sheer, corporeal density mean for reading Rimbaud? What kind of sense are we to make of this omnipresence of the body in the Rimbaldian corpus from the earliest poems celebrating the simple delight of running away from wherever one is and stretching one’s legs out under a table, to the ultimate flight away from poetry itself? In response, it argues that the body appears—often literally—as a kind of gap, breach, or aperture through which Rimbaud’s poems enter into contact with history and a larger body of other texts. Simply put, the body is privileged “lyrical material” for Rimbaud: a figure for human beings in their exposed, finite creatureliness and in their unpredictable agency and interconnectedness. Its presence in the early work allows us not only to contemplate what a strange, sensuous thing it is to be embodied, to be both singular and part of a collective, it also allows the poet to diagnose, and the reader to perceive, a set of seemingly intractable, real socio-economic, political, and symbolic problems. Rimbaud’s bodies are, in other words, utopian bodies: sites where the historical and the lyrical, the ideal and the material, do not so much cancel each other out as become caught up in one another.
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Canopy density"

1

Sánchez, Rodolfo A., Jorge J. Casal, Carlos L. Ballaré, and Ana L. Scopel. "Plant Responses to Canopy Density Mediated by Photomorphogenic Processes." In International Crop Science I, 779–86. Madison, WI, USA: Crop Science Society of America, 2015. http://dx.doi.org/10.2135/1993.internationalcropscience.c124.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Mitra, Sisir, and P. K. Pathak. "Orchard management." In Guava: botany, production and uses, 172–85. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789247022.0008.

Full text
Abstract:
Abstract Commercial production from a guava orchard begins on the third year after planting and cropping may continue for 40 years or more. The performance of an orchard depends on its management, which includes water and nutrient management, selection of the correct cultivars, planting technique, canopy management for flowering and fruiting, and improved light efficiency through pruning to optimize the quality of young and bearing trees. This chapter provides information on planting system, planting density, training and pruning, intercropping, and weed control in guava orchards.
APA, Harvard, Vancouver, ISO, and other styles
3

Ribeiro, Sérvio Pontes, Yves Basset, and Roger Kitching. "Density of Insect Galls in the Forest Understorey and Canopy: Neotropical, Gondwana or Global Patterns?" In Neotropical Insect Galls, 129–41. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-017-8783-3_8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Yavari, Farzad, and Hormoz Sohrabi. "Estimation of Available Canopy Fuel of Coppice Oak Stands Using Low-Density Airborne Laser Scanning (LiDAR) Data." In Advances in Remote Sensing and Geo Informatics Applications, 171–73. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-01440-7_40.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Saha, Asish, Manoranjan Ghosh, Subodh Chandra Pal, Indrajit Chowdhuri, Rabin Chakrabortty, Paramita Roy, Biswajit Das, and Sadhan Malik. "Assessment of Forest Cover Dynamics using Forest Canopy Density Model in Sali River Basin: A Spill Channel of Damodar River." In Spatial Modeling in Forest Resources Management, 365–84. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-56542-8_15.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Boote, K. J., and J. W. Jones. "Equations to Define Canopy Photosynthesis from Quantum Efficiency, Maximum Leaf Rate, Light Extinction, Leaf Area Index, and Photon Flux Density." In Progress in Photosynthesis Research, 415–18. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-017-0519-6_85.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Kassem, Youssef, Hüseyin Gökçekuş, and Hüseyin Çamur. "Prediction of Kinematic Viscosity and Density of Biodiesel Produced from Waste Sunflower and Canola Oils Using ANN and RSM: Comparative Study." In Advances in Intelligent Systems and Computing, 880–87. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-35249-3_117.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

"density [n] [US], canopy." In Encyclopedic Dictionary of Landscape and Urban Planning, 231. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-540-76435-9_3187.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

"canopy density [n] [US]." In Encyclopedic Dictionary of Landscape and Urban Planning, 110. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-540-76435-9_1576.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Marino, Eva, Stefano Arellano-Pérez, Santiago Martín-Alcón, and José Luis Tomé. "Canopy fuel modelling in Mediterranean forest stands with airborne LiDAR data at regional scale: preliminary results." In Advances in Forest Fire Research 2022, 1416–22. Imprensa da Universidade de Coimbra, 2022. http://dx.doi.org/10.14195/978-989-26-2298-9_215.

Full text
Abstract:
Canopy fuel characterization is highly relevant for wildfire prevention, especially in the context of extreme events involving crown fires. Airborne laser scanning has been proven very useful to retrieve 3D forest structure at large scales, becoming freely available in many countries in the recent years which provide an opportunity to map fuel parameters that are critical for fire behaviour simulation. Previous studies on canopy fuel modelling predict canopy base height (CBH), fuel load (CFL) and bulk density (CBD) mainly in tree species from temperate conifer forest, with specific models still lacking for the main Mediterranean forest stands and especially deciduous species. This work presents preliminary results of models obtained from low density airborne LiDAR data (1.5 p/m2) for canopy fuel characterization of critical structural variables (CBH, CFL and CBD) in the main Mediterranean forest stands existing in Andalusia region, including Pinus sp, Quercus sp and Eucalyptus sp tree species. A set of 750 plots are used to characterize canopy fuels in 15 different forest stands representative of Mediterranean tree species, with a samplig design that consider structural heterogeneity in a wide study area (29000 km2). Different modelling techniques are tested to selected the best formulation and input LiDAR metrics to be included in the final models for each fuel parameter, that are used to generate high resolution maps of canopy fuels at regional scale.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Canopy density"

1

Jun Zhang, Yi-Ming Wang, Qiao-Xue Dong, and Jia-Lin Hou. "Effect of Different Planting Density on Cotton Canopy Structure, Canopy Photosynthesis and Yield Formation." In 2006 Portland, Oregon, July 9-12, 2006. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2006. http://dx.doi.org/10.13031/2013.20608.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Bates, Jordan Steven, Carsten Montzka, Marius Schmidt, and Francois Jonard. "fUAS LiDAR Crop LAI Estimations from Canopy Density." In IGARSS 2021 - 2021 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2021. http://dx.doi.org/10.1109/igarss47720.2021.9553229.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Crifò, Camilla, Ellen D. Currano, Andres Baresch, and Carlos Jaramillo. "VEIN DENSITY: WHY SHOULD WE ACCESS THE FOREST CANOPY?" In GSA Annual Meeting in Denver, Colorado, USA - 2016. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016am-287876.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Li, Xiujuan, Yongxin Liu, Wei Xu, Pingping Huang, and Wenxue Fu. "Forest Canopy Volume Density Index Inversion Method Using Polarization Decomposition." In 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall). IEEE, 2019. http://dx.doi.org/10.1109/piers-fall48861.2019.9021425.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Sulistiyono, Nurdin, Khairil Amri, Pindi Patana, and Achmad Siddik Thoha. "Spatial Model of Canopy Density in Mangrove Forest of Percut Sei Tuan." In International Conference on Natural Resources and Technology. SCITEPRESS - Science and Technology Publications, 2019. http://dx.doi.org/10.5220/0008388000420045.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Edburg, Steven, David Stock, Brian Lamb, and Harold Thistle. "Large Eddy Simulation of Near-Field Dispersion Within and Above Forest Canopies." In ASME 2005 Fluids Engineering Division Summer Meeting. ASMEDC, 2005. http://dx.doi.org/10.1115/fedsm2005-77463.

Full text
Abstract:
Numerical simulations were conducted to investigate the feasibility of predicting near field concentrations of a tracer gas within and above forest canopies. The current research is geared towards providing forest managers with a tool for developing anti-aggregation techniques to control the bark beetle. Several field experiments have been conducted in different forest canopies linking tracer gas concentration fields with meteorological and canopy parameters. Field experiment results are site and situation specific. Numerical simulations are far less expensive and allow for variation in virtually all flow parameters such as atmospheric stability, wind speed and direction, and turbulence intensity. As a first step, a CFD simulation has been used to study dispersion in a generic lodgepole pine forest canopy based on leaf area index (LAI) and stem density. Steady Reynolds Averaged Navier Stokes (RANS) solutions were computed using the k-ε and Reynolds Stress Model (RSM) turbulence closure models. These solutions provide insight into in-canopy dispersion; however they do not fully capture the dynamics of the flow. The current work uses large eddy simulation (LES). LES resolves large flow dominated eddies while modeling smaller eddies using a sub grid scale model. Unsteady LES, can be used to capture the dynamics of flow within a canopy, including large rolling eddies above the canopy, bursting and sweeping within the canopy, multiple shear layers, and drainage flows.
APA, Harvard, Vancouver, ISO, and other styles
7

Yang, Cunjian, He Huang, Shaou Han, and Jing Ni. "Estimating forest canopy density using LANDSAT TM data based on sub-compartment objects." In IGARSS 2013 - 2013 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2013. http://dx.doi.org/10.1109/igarss.2013.6721331.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Dai, Leiyu, Shihua Li, Yankai Zhao, Sen Lin, and Ze He. "Forest Canopy Leaf Area Density Estimation Based on Airborne and Terrestrial Lidar Data." In IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2018. http://dx.doi.org/10.1109/igarss.2018.8518212.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Haibo Yao, Lei Tian, Lie Tang, and Kelly Thorp. "Corn Canopy Reflectance Study With A Real-Time High-Density Spectral-Image Mapping System." In 2002 Chicago, IL July 28-31, 2002. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2002. http://dx.doi.org/10.13031/2013.10950.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Zancanaro, E., A. Gertsis, G. Vellidis, F. Marinello, and F. Morari. "Developing crop canopy model for irrigation of high-density olive groves by using UAV imagery." In 12th European Conference on Precision Agriculture. The Netherlands: Wageningen Academic Publishers, 2019. http://dx.doi.org/10.3920/978-90-8686-888-9_52.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Canopy density"

1

Short, Mary, and Sherry Leis. Vegetation monitoring in the Manley Woods unit at Wilson’s Creek National Battlefield: 1998–2020. Edited by Tani Hubbard. National Park Service, June 2022. http://dx.doi.org/10.36967/nrr-2293615.

Full text
Abstract:
Natural resource management at Wilson’s Creek National Battlefield (NB) is guided by our understanding of the woodlands and prairies at the time of the Civil War battle in 1861. This report is focused on the Manley Woods unit of the park. This unit is an oak-hickory woodland in the Springfield Plain subsection of the Ozarks. Canopy closure for Missouri oak woodlands can be highly variable and ranges from 30–100% across the spectrum of savanna, open woodland, and closed woodland types. In 1861, the woodland was likely a savanna community. Changes in land use (e.g., fire exclusion) caused an increase in tree density in woodlands at Wilson’s Creek NB and across the Ozarks. Savannas and open woodlands transitioned to closed canopy woodlands over time. Park management plans include restoring the area to a savanna/open woodland structure. Prescribed fire was reintroduced to Wilson’s Creek NB in 1988 and continues as the primary mechanism for reducing the tree canopy. The Manley Woods unit of Wilson’s Creek NB has been subject to intense natural and anthropogenic disturbance events such as a tornado in 2003, timber removal in 2005, prescribed fires in 2006, 2009, and 2019, an ice storm in 2007, and periodic drought. The Heartland Inventory and Monitoring Network (hereafter, Heartland Network) installed four permanent monitoring sites within the Manley Woods area of the park in 1997. Initially, we assessed ground flora and regeneration within the sites (1998–1999). We added fuel sampling after the 2003 tornado. Although overstory sampling occurred prior to the tornado, the protocol was not yet stabilized and pre-2003 overstory data were not included in these analyses. In this report, we focus on the overstory, tree regeneration, and ground cover metrics; ground flora data will be assessed in future analyses. Heartland Network monitoring data reveal that Manley Woods has undergone substantial change in canopy cover and midstory trees since 1998. While basal area and density metrics classify Manley Woods as an open woodland, the closed canopy of the midstory and overstory reveal a plant community that is moving toward closed woodland or forest structure. The most recent fire in 2019 was patchy and mild, resulting in continued increases in fuels. Ground cover metrics indicate infrequent disturbance since leaf litter continued to increase. Management objectives to restore savanna or woodland composition and structure to the Manley Woods overstory, regeneration layer, and ground cover will require implementation of prescribed fire in the future. Repeated fires can thin midstory trees and limit less fire tolerant early seral species. Additionally, mechanical or chemical treatments to reduce undesirable tree species should be considered for woodland restoration. Decreasing canopy closure is an important and essential step toward the restoration of a functioning savanna/open woodland plant community in Manley Woods. Treatments that thin the midstory and reduce fuel loading will also benefit these plant communities. With the anticipated changing climate, maintaining an open woodland community type may also provide resilience through management for native species tolerant of increasingly warmer temperatures.
APA, Harvard, Vancouver, ISO, and other styles
2

Saltus, Christina, and Eric Britzke. Literature review : macrohabitat metrics to identify presence of chiroptera on the landscape in the United States. Engineer Research and Development Center (U.S.), September 2022. http://dx.doi.org/10.21079/11681/45523.

Full text
Abstract:
This special report reviews current scientific literature to identify the most commonly cited metrics used to describe the macrohabitat criteria important for Chiroptera presence in the United States. The review evaluates 69 scientific articles from 1994 to 2018. The most commonly cited metrics were divided into four main categories: tree-species-level metrics, landscape-level metrics, distance metrics, and topographic and atmospheric metrics. Of all metrics found, the top six most common metrics noted across all articles were percent canopy cover, diameter at breast height (DBH), forest type, distance to water, distance to roads or other urban features, and tree density. In addition, 27 of the 47 (57%) bat species located within the United States were represented. These metrics provide important insight into the regional or national species-level distribution and assist with modeling the relationship between species distribution and habitat change.
APA, Harvard, Vancouver, ISO, and other styles
3

Seginer, Ido, Daniel H. Willits, Michael Raviv, and Mary M. Peet. Transpirational Cooling of Greenhouse Crops. United States Department of Agriculture, March 2000. http://dx.doi.org/10.32747/2000.7573072.bard.

Full text
Abstract:
Background Transplanting vegetable seedlings to final spacing in the greenhouse is common practice. At the time of transplanting, the transpiring leaf area is a small fraction of the ground area and its cooling effect is rather limited. A preliminary modeling study suggested that if water supply from root to canopy is not limiting, a sparse crop could maintain about the same canopy temperature as a mature crop, at the expense of a considerably higher transpiration flux per leaf (and root) area. The objectives of this project were (1) to test the predictions of the model, (2) to select suitable cooling methods, and (3) to compare the drought resistance of differently prepared seedlings. Procedure Plants were grown in several configurations in high heat load environments, which were moderated by various environmental control methods. The difference between the three experimental locations was mainly in terms of scale, age of plants, and environmental control. Young potted plants were tested for a few days in small growth chambers at Technion and Newe Ya'ar. At NCSU, tomato plants of different ages and planting densities were compared over a whole growing season under conditions similar to commercial greenhouses. Results Effect of spacing: Densely spaced plants transpired less per plant and more per unit ground area than sparsely spaced plants. The canopy temperature of the densely spaced plants was lower. Air temperature was lower and humidity higher in the compartments with the densely spaced plants. The difference between species is mainly in the canopy-to-air Bowen ratio, which is positive for pepper and negative for tomato. Effect of cooling methods: Ventilation and evaporative pad cooling were found to be effective and synergitic. Air mixing turned out to be very ineffective, indicating that the canopy-to-air transfer coefficient is not the limiting factor in the ventilation process. Shading and misting, both affecting the leaf temperature directly, proved to be very effective canopy cooling methods. However, in view of their side effects, they should only be considered as emergency measures. On-line measures of stress: Chlorophyll fluorescence was shown to accurately predict photosynthesis. This is potentially useful as a rapid, non-contact way of assessing canopy heat stress. Normalized canopy temperature and transpiration rate were shown to correlate with water stress. Drought resistance of seedlings: Comparison between normal seedlings and partially defoliated ones, all subjected to prolonged drought, indicated that removing about half of the lowermost leaves prior to transplanting, may facilitate adjustment to the more stressful conditions in the greenhouse. Implications The results of this experimental study may lead to: (1) An improved model for a sparse canopy in a greenhouse. (2) A better ventilation design procedure utilizing improved estimates of the evaporation coefficient for different species and plant configurations. (3) A test for the stress resistance of transplants.
APA, Harvard, Vancouver, ISO, and other styles
4

Leis, Sherry. Vegetation community monitoring at Lincoln Boyhood National Memorial: 2011–2019. National Park Service, April 2021. http://dx.doi.org/10.36967/nrr-2284711.

Full text
Abstract:
Lincoln Boyhood National Memorial celebrates the lives of the Lincoln family including the final resting place of Abraham’s mother, Nancy Hanks Lincoln. Lincoln’s childhood in Indiana was a formative time in the life our 16th president. When the Lincoln family arrived in Indiana, the property was covered in the oak-hickory forest type. They cleared land to create their homestead and farm. Later, designers of the memorial felt that it was important to restore woodlands to the site. The woodlands would help visitors visualize the challenges the Lincoln family faced in establishing and maintaining their homestead. Some stands of woodland may have remained, but significant restoration efforts included extensive tree planting. The Heartland Inventory and Monitoring Network began monitoring the woodland in 2011 with repeat visits every four years. These monitoring efforts provide a window into the composition and structure of the wood-lands. We measure both overstory trees and the ground flora within four permanently located plots. At these permanent plots, we record each species, foliar cover estimates of ground flora, diameter at breast height of midstory and overstory trees, and tree regeneration frequency (tree seedlings and saplings). The forest species composition was relatively consistent over the three monitoring events. Climatic conditions measured by the Palmer Drought Severity Index indicated mild to wet conditions over the monitoring record. Canopy closure continued to indicate a forest structure with a closed canopy. Large trees (>45 cm DBH) comprised the greatest amount of tree basal area. Sugar maple was observed to have the greatest basal area and density of the 23 tree species observed. The oaks characteristic of the early woodlands were present, but less dominant. Although one hickory species was present, it was in very low abundance. Of the 17 tree species recorded in the regeneration layer, three species were most abundant through time: sugar maple (Acer saccharum), red bud (Cercis canadensis), and ash (Fraxinus sp.). Ash recruitment seemed to increase over prior years and maple saplings transitioned to larger size classes. Ground flora diversity was similar through time, but alpha and gamma diversity were slightly greater in 2019. Percent cover by plant guild varied through time with native woody plants and forbs having the greatest abundance. Nonnative plants were also an important part of the ground flora composition. Common periwinkle (Vinca minor) and Japanese honeysuckle (Lonicera japonica) continued to be the most abundant nonnative species, but these two species were less abundant in 2019 than 2011. Unvegetated ground cover was high (mean = 95%) and increased by 17% since 2011. Bare ground increased from less than 1% in 2011 to 9% in 2019, but other ground cover elements were similar to prior years. In 2019, we quantified observer error by double sampling two plots within three of the monitoring sites. We found total pseudoturnover to be about 29% (i.e., 29% of the species records differed between observers due to observer error). This 29% pseudoturnover rate was almost 50% greater than our goal of 20% pseudoturnover. The majority of the error was attributed to observers overlooking species. Plot frame relocation error likely contributed as well but we were unable to separate it from overlooking error with our design.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Canopy density' for particular source types:
Journal articles Dissertations / Theses
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography