A Methodology for the Automated Delineation of Crop Tree Crowns from UAV-Based Aerial Imagery by Means of Morphological Image Analysis

The popularisation of aerial remote sensing using unmanned aerial vehicles (UAV), has boosted the capacities of agronomists and researchers to offer farmers valuable data regarding the status of their crops. This paper describes a methodology for the automated detection and individual delineation of tree crowns in aerial representations of crop fields by means of image processing and analysis techniques, providing accurate information about plant population and canopy coverage in intensive-farming orchards with a row-based plant arrangement. To that end, after pre-processing initial aerial captures by means of photogrammetry and morphological image analysis, a resulting binary representation of the land plot surveyed is treated at connected component-level in order to separate overlapping tree crown projections. Then, those components are morphologically transformed into a set of seeds with which tree crowns are finally delineated, establishing the boundaries between them when they appear overlapped. This solution was tested on images from three different orchards, achieving semantic segmentations in which more than 94% of tree canopy-belonging pixels were correctly classified, and more than 98% of trees were successfully detected when assessing the methodology capacities for estimating the overall plant population. According to these results, the methodology represents a promising tool for automating the inventorying of plants and estimating individual tree-canopy coverage in intensive tree-based orchards.

USO DO SOFTWARE AQUACROP PARA SIMULAR A RESPOSTA DO FEIJÃO À DIFERENTES REGIMES DE IRRIGAÇÃO

USO DO SOFTWARE AQUACROP PARA SIMULAR A RESPOSTA DO FEIJÃO À DIFERENTES REGIMES DE IRRIGAÇÃO MONALISA SOARES COSTA1*; EVERARDO CHARTUNI MANTOVANI2; FERNANDA LAMEDE FERREIRA DE JESUS3; ARTHUR CARNIATO SANCHES 4; JHON LENNON BEZERRA DA SILVA5 E JANNAYLTON ÉVERTON DE OLIVEIRA SANTOS6 1 Bolsista de longa duração – desenvolvimento tecnológico, Instituto Nacional do Semiárido, rua Antônio Aragão, 169, Nova Brasília, CEP 49680-000, Nossa Senhora da Glória, Sergipe, Brasil, Parte da dissertação de mestrado, [email protected] 2Professor Sênior doutor, Departamento de Engenharia Agrícola, Universidade Federal de Viçosa, Av. Peter Henry Rolfs, s/n - Campus Universitário, 36570-900, Viçosa, Minas Gerais, Brasil, [email protected] 3Professora Doutora, Departamento de Engenharia Agrícola, Universidade Federal Rural da Amazônia, Campus Tomé-Açu, Rod. PA 140, km 03, 68680-000, Tomé-Açu, PA, Brasil, [email protected] 4Professor Doutor, Faculdade de Ciências Agrárias, Universidade Federal da Grande Dourados, Rod. Dourados-Itahum, km 12 – Cidade Universitária, 79804-970, Dourados, MS, Brasil, [email protected] 5 Doutorando em Engenharia de Agrícola, Departamento de Engenharia, UFRPE, Rua Dom Manuel de Medeiros, s/n - Dois Irmãos, 52171-900, Recife, Pernambuco, Brasil, [email protected] 6 Professor Doutor, Departamento de Engenharia Agrícola, Universidade Federal Rural da Amazônia, Campus Tomé-Açu, Rod. PA 140, km 03, 68680-000, Tomé-Açu, PA, Brasil, [email protected] 1 RESUMO Os softwares de simulação de crescimento e desenvolvimento das culturas no campo têm tido bastante aplicação, visto o objetivo de técnicos e pesquisadores em evitar perdas no campo e almejar melhorias a cada cultivo. O feijão é bastante cultivado e consumido no Brasil, o que atrai atenção para o ajuste do software AquaCrop à cultura nas condições edafoclimáticas brasileiras. O objetivo deste trabalho foi analisar a resposta do software AquaCrop quando ajustado para condições de ambiente e irrigação em que o feijoeiro foi cultivado. Observou-se dados simulados semelhantes e em concordância estatística com o observado, com maiores diferenças no acúmulo de biomassa e balanço hídrico ao longo do ciclo da cultura. A semelhança entre os dados simulados e observados na cobertura do dossel ao longo do ciclo da cultura traduzem uma boa resposta da equação utilizada para converter o índice de área foliar em cobertura do dossel para a cultura do feijão. Conclui-se com o estudo, que o software AquaCrop é confiável para a simulação do crescimento e desenvolvimento do feijão, pois os dados obtidos em campo são semelhantes aos simulados pelo modelo. Palavras-chave: manejo, eficiência do uso da água, função de produção. COSTA, M. S.; MANTOVANI, E. C.; JESUS, F. L. F.; SANCHES, A. C.; SILVA, J. L. B.; SANTOS, J. E. O. U 2 ABSTRACT The simulation software’s of crop growth and development in the field has had many applications, since the aim of technicians and research in avoiding losses on the field and to target for improvements in each crop. The crop bean is highly cultivated and consumed in Brazil, what draws attention to the adjustment of the AquaCrop software for this crop under Brazilian edaphoclimatic conditions. This study aimed to analyze the response of the AquaCrop when adjusted for irrigation and greenhouse conditions in which the crop bean was cultivated. It was observed simulated data were similar and in statistical accordance with the observance in the field, to higher differences in biomass accumulation and water balance throughout the crop cycle. The similarity between the simulated and observed data for canopy coverage throughout the crop cycle translates a good answer of the equation used to convert the leaf area index canopy coverage for crop bean. We concluded with this study, that AquaCrop software is reliably simulating the growth and development of the crop bean because the data obtained on the field are similar to those simulated by the model. Keywords: management, water use efficiency, production function.

Analisis Tutupan Mangrove Taman Nasional Berbak–Sembilang melalui Citra Landsat-8 dan Pemantauan LAI

Berbak Sembilang National Park of South Sumatra Region (BSNP South Sumatera) is the largest mangrove ecosystem in the western part of Indonesia. Monitoring of mangrove coverage in BSNP South Sumatera carried out using Landsat-8 imagery data based on NDVI values (Normalized Difference Vegetation Index) integrated with mangrove LAI (Leaf Area Index) data. The research purpose was to analyze the mangrove coverage and mapping the density of the mangrove vegetation canopy with the integration of remote sensing data and LAI. This research conducted field survey with LAI measurement of mangrove canopy coverage and integrated with remote sensing data to validate map. The determination and correlation coefficient of NDVI and LAI value of canopy coverage was high (R2 = 0.69 ; r = 83.07).The results of research indicated that the overall distribution of the mangrove area was 94,622.05 ha. The NDVI image integration map with LAI resulted in 4 mangrove canopy density classes consisted of rare canopy (688.80 ha ; 0.73%), moderately dense canopy (1,139.55 ha ; 1.2%), dense canopy (35,003.46 ha ; 37%), and very dense canopy (57,790.20 ha ; 61.07%). Taman Nasional Berbak Sembilang wilayah Sumatera Selatan (TNBS Sumsel) merupakan kawasan ekosistem mangrove terluas di wilayah Indonesia bagian barat. Pemantauan kerapatan kanopi vegetasi mangrove di TNBS Sumsel dilakukan menggunakan data Citra Landsat-8 berdasarkan nilai NDVI (Normalized Difference Vegetation Index) yang diintegrasikan dengan data LAI (Leaf Area Index) mangrove di lapangan. Penelitian ini bertujuan untuk menganalisis tutupan vegetasi mangrove dan memetakan sebaran kerapatan kanopi mangrove dengan integrasi data penginderaan jauh dan LAI. Penelitian ini menggunakan metode pengolahan data survei lapangan dan hasil pengolahan citra satelit. Nilai koefisien determinasi dan korelasi antara nilai NDVI dengan nilai LAI tutupan Kanopi di Lapangan dikategorikan tinggi (R2 = 0,69 ; r = 83,07). Hasil penelitian menunjukkan tutupan mangrove secara keseluruhan seluas 94.622,05 ha. Peta integrasi citra NDVI dengan LAI mangrove di lapangan menghasilkan 4 kelas kerapatan kanopi mangrove yakni kanopi jarang seluas 688,80 ha (0,73%), kanopi sedang seluas 1.139,55 ha (1,2%), kanopi lebat seluas 35.003,46 ha (37%), dan kanopi sangat lebat seluas 57.790,20 ha (61,07%).

Branch Angle and Leaflet Shape are Associated with Canopy Coverage in Soybean

Early canopy coverage is a desirable trait that promotes faster ground coverage, resulting in reduced soil evaporation, increased light interception, biomass production and weed suppression, all of which are important determinants of yield in soybean (Glycine max). Variation in traits comprising shoot architecture can influence canopy coverage, canopy light interception, canopy-level photosynthesis, and source-sink partitioning efficiency. However, little is known about the extent of phenotypic diversity of shoot architecture traits and their genetic control in soybean. Thus, we sought to understand the contribution of shoot architecture traits to canopy coverage and to determine the genetic control of these traits. We examined the natural variation for shoot architecture traits in a set of 399 diverse maturity group I soybean (SoyMGI) accessions to identify relationships between traits, and to identify loci that are associated with canopy coverage and shoot architecture traits. Canopy coverage was correlated with branch angle, number of branches, plant height and leaf shape. Using previously collected 50K SNP data on the SoyMGI panel, we identified QTL associated with branch angle, number of branches, branch density, leaf length/width ratio, days to flowering, maturity, plant height, number of nodes and stem termination. In many cases QTL intervals overlapped with previously described genes or QTL. Of particular note, we found QTL associated with branch angle and leaflet shape located on chromosomes 19 and 4, respectively, and these QTL overlapped with QTL associated with canopy coverage, suggesting the importance of branch angle and leaflet shape in determining canopy coverage. Taken together, our results highlight the role individual architecture traits play in canopy coverage and contribute information on their genetic control that could help facilitate future efforts in their genetic manipulation.

The Legacy of Hurricanes, Historic Land Cover, and Municipal Ordinances on Urban Tree Canopy in Florida (United States)

Urban Tree Canopy (UTC) greatly enhances the livability of cities by reducing urban heat buildup, mitigating stormwater runoff, and filtering airborne particulates, among other ecological services. These benefits, combined with the relative ease of measuring tree cover from aerial imagery, have led many cities to adopt management strategies based on UTC goals. In this study, we conducted canopy analyses for the 300 largest cities in Florida to assess the impacts of development practices, urban forest ordinances, and hurricanes on tree cover. Within the cities sampled, UTC canopy ranged from 5.9% to 68.7% with a median canopy coverage of 32.3% Our results indicate that the peak gust speeds recorded during past hurricanes events were a significant predictor of canopy coverage (P-value = <0.001) across the sampled cities. As peak gust speeds increased from 152 km/h (i.e., a lower-intensity Category 1 storm) to 225 km/h (lower-intensity Category 4 and the maximum gusts captured in our data), predicted canopy in developed urban areas decreased by 7.7%. Beyond the impacts of hurricanes and tropical storms, we found that historic landcover and two out of eight urban forest ordinances were significant predictors of existing canopy coverage (P-landcover <0.001; P-tree preservation ordinance = 0.02, P-heritage tree ordinance = 0.03). Results indicate that local policies and tree protections can protect or enhance urban tree canopy, even in the face of rapid development and periodic natural disturbances.

Effects of environmental factors on the behaviour and nest group sizes of Smith's bush squirrels, Paraxerus cepapi, in a Zambezian bioregion

The responses of wildlife to environmental factors are of conservation importance. However, the absence of relevant information due to inadequate studies, and lack of understanding of the influences of environmental factors on wildlife, particularly in the Zambezian bioregion, remain a conservation concern. For instance, there is a shortage of knowledge on the relationship between fixed effects of environmental factors and behaviour as well as nest group sizes of Smith’s bush squirrels, Paraxerus cepapi Smith, 1836. Our study examined the relationship between fixed effects of several environmental factors (i.e., with focus on ecological factors) and the behaviour as well as nest group sizes of the bush squirrels in and around Zambia’s Chembe Bird Sanctuary (CBS). Flight initiation distances (FIDs) as an index of bush squirrel behaviour, and nest group sizes were simultaneously surveyed to understand the drivers of biological and population responses, respectively. The results revealed that higher tree height (m) and larger canopy coverage (%) could increase FIDs for bush squirrels. The nest group sizes of bush squirrels could also increase with canopy coverage (%) and presence of termite mounds. By focusing on the two different squirrels' responses, the results of this study highlight the most important environmental factors to consider in minimizing the impacts of human activities on bush squirrels, especially in conservation planning and management by taking into consideration the bush squirrels’ natural history, habitat protection and safe distance between humans and bush squirrels.

Phenological evaluation methods in native plant species

Phenology is an important tool used for the knowledge and study of native species, being necessary that they are conducted in a uniform way and evaluated the same characteristics, both quantitative and qualitative. In this sense, this work aimed to gather the main studies, proposing a union in the methodology for this type of study. For effective work, five to ten individuals should be sampled by species, checking the presence or absence of phenophases, visually quantifying the percentage of canopy coverage and classifying them as to their occurrence and regularity and finally checking the synchronization of events in species within the community. To carry out phenological studies, five to ten individuals must be sampled, and the presence or absence of phenophases, defoliation, sprouting, leaf expansion and maintenance of foliage in the canopy, flower buds emission, flowering in progress, end of flowering, forming fruits, ripe fruits and falling fruits / dispersing seeds, visually quantify the percentage of canopy coverage, and then estimate its synchronization and classification as to the frequency and regularity of occurrence.

Effects of Topography on Planted Trees in a Headwater Catchment on the Chinese Loess Plateau

The Chinese Loess Plateau (CLP) is known for its complex topography of hills and gullies, and lots of human land-use management activities have been put into practice to sustain the soil, water and other natural resources. Afforestation has been widely applied on the CLP and it’s important to understand the effects of topography on these planted trees. However, the coarse spatial resolution of remote sensing data makes it insensitive to local topography, and the traditional in-situ measurements would consume vast amounts of time and resources. In this study, a small headwater catchment of the CLP was selected to study the effects of topography on the planted trees. Low altitude unmanned aerial vehicle based light detection and ranging (UAV-based LiDAR) technology was utilized to obtain high-resolution topography and vegetation structure data. Results showed that the middle transition zone (mid-transition, slope > 45°) was an important boundary of topography in the gully area of the CLP. In the forested catchment, the area of the mid-transition zone had the lowest of tree density, canopy coverage and leaf area index due to steep slope gradient. The tall trees ten to twenty meters high were concentrated in the downhill area, which had the highest canopy coverage and leaf area index. Elevation had significant linear relationships with canopy coverage and leaf area index (p < 0.001), which revealed the impact of topography on the forest indexes of the afforestation catchment. We concluded that the high-resolution LiDAR technology facilitated the research of topography and forest interactions in land surface.