This document is a brief summary of the partial tree inventory along the main roads in Naga City.The data described in this paper came from the fieldwork activities conducted from December 05, 2017 to May 23, 2019 and included portions of the 17 barangays in Naga City.

Fieldwork activities for this joint project were participated by volunteers from They Grey We Green, SULOG (Sumaro sa Salog), private individuals, environmental management students, citizen scientists, and headed by the Institute for Environmental Conservation and Research of the Ateneo de Naga University (ADNU-INECAR).

Tree census was facilitated using a Kobo Collect android application developed in part by the INECAR team. Using the application, the volunteers geotag the trees and input important information from each of the trees like the species or local name and the barangay where it is located. In addition, the volunteers also took pictures of the trees to aid in the validation of species. After fieldwork, the volunteers send their files online to a cloud server that can be accessed through a web application, the KoboToolbox.

Data from the server was exported and downloaded for data cleaning and processing using R and RStudio. This document was also created using the said software.

Data Summary

As of May 23, 2019, a total of 2082 trees along the roadside were counted in the Project.

Please note that these tree data is PARTIAL as the tree census is far from over and was temporarily discontinued due to the lack of manpower and the onset of the COVID19 Pandemic.

The latest Tree Inventory covered portions of the 17 barangays and the trees counted are listed below. For now, the top three barangays with the most number of trees are Pacol, San Felipe, and Concepcion Pequena.

The Case for Barangay Del Rosario

Most common roadside trees in Barangay Del Rosario are shown by the following graph:

Based on the dataset, currently, the total number of trees that the Census has counted in Barangay Del Rosario is 146

Map of Plotted Trees in Barangay Del Rosario:

The volunteers gathered data from the roadside trees in the barangay as seen in the map below. Please note that the team used at most, plus or minus three (3) meters as margin of error for the acquisition of tree location (GPS coordinates). On the other hand, one may see that some trees are plotted faraway from the roadside which maybe due to poor GPS reception or outdated settings in the mobile application used in the early days of the Project.

How large are the trees along the roadside of Barangay Del Rosario?

To visualize this, the map shows the trees and their measured girth at breast height/GBH (circumference of the tree at 1.3 meters) in meters as pop up when the tree bubbles are clicked:

It is important to note that the range of tree circumference (at GBH) recorded for the 146 trees is 0.16 to 4.8 meters.

##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##  0.1600  0.6725  1.4250  1.6218  2.3600  4.8000

Also, it is interesting to note that even though the team were not able to gather the tree height data on all of the trees, the range of height for a small sample is 2.350 to 13.62 meters.

##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max.    NA's 
##   2.350   4.963   7.460   7.977  12.068  13.620     102

Tree Benefits (Ecosystem Services) that we freely enjoy here in Naga City

Before we proceed to our brief discussion on the benefits of Trees in an urban area, please take a look at the summary of the Del Rosario tree dataset:

##        V1           latitude       longitude         date          
##  Min.   :119.0   Min.   :13.62   Min.   :123.2   Length:146        
##  1st Qu.:157.2   1st Qu.:13.62   1st Qu.:123.2   Class :character  
##  Median :193.5   Median :13.62   Median :123.2   Mode  :character  
##  Mean   :195.4   Mean   :13.62   Mean   :123.2                     
##  3rd Qu.:230.8   3rd Qu.:13.62   3rd Qu.:123.2                     
##  Max.   :289.0   Max.   :13.62   Max.   :123.2                     
##                                                                    
##    barangay          local_name         initial_id             gbh        
##  Length:146         Length:146         Length:146         Min.   :0.1600  
##  Class :character   Class :character   Class :character   1st Qu.:0.6725  
##  Mode  :character   Mode  :character   Mode  :character   Median :1.4250  
##                                                           Mean   :1.6218  
##                                                           3rd Qu.:2.3600  
##                                                           Max.   :4.8000  
##                                                                           
##      height       canopy_spread tree_condition     maintenance_needs 
##  Min.   : 2.350   Min.   : NA   Length:146         Length:146        
##  1st Qu.: 4.963   1st Qu.: NA   Class :character   Class :character  
##  Median : 7.460   Median : NA   Mode  :character   Mode  :character  
##  Mean   : 7.977   Mean   :NaN                                        
##  3rd Qu.:12.068   3rd Qu.: NA                                        
##  Max.   :13.620   Max.   : NA                                        
##  NA's   :102      NA's   :146                                        
##  watering_needs  pruning_needs   other_maintenance_needs mnspecified       
##  Mode :logical   Mode :logical   Mode :logical           Length:146        
##  FALSE:60        FALSE:13        FALSE:69                Class :character  
##  TRUE :23        TRUE :70        TRUE :14                Mode  :character  
##  NA's :63        NA's :63        NA's :63                                  
##                                                                            
##                                                                            
##                                                                            
##  special_characteristics  fruiting       flowering          host        
##  Length:146              Mode :logical   Mode :logical   Mode :logical  
##  Class :character        FALSE:44        FALSE:70        FALSE:50       
##  Mode  :character        TRUE :42        TRUE :16        TRUE :36       
##                          NA's :60        NA's :60        NA's :60       
##                                                                         
##                                                                         
##                                                                         
##   habitat        other_special_characteristics scspecified       
##  Mode :logical   Min.   :0.0000                Length:146        
##  FALSE:86        1st Qu.:0.0000                Class :character  
##  NA's :60        Median :0.0000                Mode  :character  
##                  Mean   :0.2442                                  
##                  3rd Qu.:0.0000                                  
##                  Max.   :1.0000                                  
##                  NA's   :60                                      
##  characteristics       popup          
##  Length:146         Length:146        
##  Class :character   Class :character  
##  Mode  :character   Mode  :character  
##                                       
##                                       
##                                       
##

and the following parameters collected:

##  [1] "V1"                            "latitude"                     
##  [3] "longitude"                     "date"                         
##  [5] "barangay"                      "local_name"                   
##  [7] "initial_id"                    "gbh"                          
##  [9] "height"                        "canopy_spread"                
## [11] "tree_condition"                "maintenance_needs"            
## [13] "watering_needs"                "pruning_needs"                
## [15] "other_maintenance_needs"       "mnspecified"                  
## [17] "special_characteristics"       "fruiting"                     
## [19] "flowering"                     "host"                         
## [21] "habitat"                       "other_special_characteristics"
## [23] "scspecified"                   "characteristics"              
## [25] "popup"

The data above is a subset of the whole tree data set of the Trees in the City Project that volunteers and citizen scientists had contributed by doing actual fieldwork under the sun or rain. With this, the authors are truly grateful to the volunteers and sponsors.

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The Benefits of Trees

Aside from the beauty and shade these Urban Trees provide, the trees’ most important ecosystem services are tied to its ability to photosynthesize, that is, its ability to absorb carbon dioxide, take in water and nutrients from the soil, make food for itself (carbohydrates and sugars), and give off oxygen and water.

Trees are able to lessen flooding and soil erosion as the trees’ roots are continously absorbing water and holding our precious soil.

Ever wonder why we feel a lot cooler under the shade of the tree or why we usually park our cars under the shade of a tree? Because aside from the leaves and thick foliage that protect us from direct sunlight, the water vapor that the tree produces through photosynthesis, escapes in the small leaf openings called stomata (stomates). Because of the evaporation of these water vapor, we feel a significantly lower temperature under a tree.

Trees absorb Carbon Dioxide and store most of them in their bodies as wood and biomass. Because of this, maintaining our existing trees and planting more of them helps in our fight against the effects of the changing climate, that we now call as Climate Emergency.

In line with this, Trees clean the air we breathe by absorbing or removing pollutants in the air. Do you know that Oxygen, which is the air we breathe, and Water, which is essential in our daily life, are just the “waste materials” of a plant’s photosynthesis?

On the other hand, Carbon Dioxide , which we humans and animals exhale, is in turn needed by the plants to live and grow. Too bad that in the present, the amount of greenhouse gases including Carbon Dioxide in the atmosphere has far exceeded the ability of plants and plankton to take them up, causing more complicated problems.

When we cut the trees and allow them to rot or burn, most of the the stored carbon that they successfully absorbed while they were still alive, go back to the atmosphere, adding more carbon dioxide and greenhouse gases that make our planet hotter and hotter each year.

Trees serve as habitats of other organisms thus enabling a wildlife to thrive even in cities and urban areas. Most of these trees in our city support a wide variety of wildlife such as orchids and ferns, birds, bees, butterflies, and insects. In nature, an ecosystem with more diverse the species, it is more likely to become more stable and resilient from disturbance. Like the trees, these organisms also bring us benefits such as pollination and pest control to name a few. Trees promote biodiversity in urban areas. See for example the data on Barangay Del Rosario trees as hosts or habitats of plants and animals:

##    Mode   FALSE    TRUE    NA's 
## logical      50      36      60

36 out of the inventoried trees serve as host for other wildlife.

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There are still many more reasons why trees are important inside our cities and urban areas, but we hope that the reasons cited above will help us realize their importance in our daily lives.

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