Comprehensive study on the amount of CO₂ absorbed by vegetation: A case study in Ho Chi Minh city, Vietnam

Abstract

The city Ho Chi Minh (HCMC) is one of the largest cities in Vietnam with the most dramatically economic development rate. Along with the economic development, the urbanization process in this city is also taking place very fastly. Due to the rapid urbanization and development, the emission rate from the industry and transportation leads to the increase in the amount of carbon dioxide (CO2) which has been worsening the climate change. Protecting forests and conducting afforestation so that CO2 is transformed to nutrition through photosynthetic conversion is one of the most effective ways to mitigate the effects of climate change. As a result, the accumulation of CO2 emissions has become a global concern. Vegetation absorbs carbon dioxide, helps to conserve the environment, produces oxygen, reduces noise, and helps to stabilize subsurface water. This paper highlights the results of ENVI software which was used to interpret remote sensing images and Arcgis to evaluate the amount of carbon dioxide absorbed by vegetation in each administrative unit: district in HCMC and ward. According to the obtained results, the amount of CO2 absorbed in urban districts “District 1”, “District 3”, “District 4”, “District 5”, “Phu Nhuan District” is immensely low due to the high population density in the center of city. The population is mainly concentrated in the center districts but land area for vegetation is low. Regarding the suburban area, with mangrove forests, Can Gio District has the highest amount of CO2 absorbed of 35,894.075 tons/day and followed by Cu Chi District with 21,548.48 tons/day. It can be indicated that Can Gio and Cu Chi districts improtantly function like the greenhouse gas sinks for the whole HCMC. The success of this study could contribute to climate change mitigation and support in urban and land planning, as well as resettlement policies. Aside from that, CO2 emission and absorption assessment and evaluation in large–scale cities like HCMC has become a crucial, urgent, and practical issue nowadays.

Synthesis of Bis(3‐indolyl)methanes Mediated by Potassium tert‐Butoxide

“… [14] Other examples also include the use of metal‐free oxidative reactions. [ 15 , 16 ] Recently, several examples have been reported using aryl amines ( 1 ), [17] aldehydes ( 2 ),[ 18 , 19 , 20 , 21 , 22 ] ketones ( 3 ),[ 23 , 24 ] benzyl amines ( 4 )[ 16 , 25 ] and benzyl alcohols ( 5 )[ 26 , 27 , 28 ] as starting materials (Scheme 1 ).…”

Atomic Spectrometry Update: review of advances in elemental speciation

“…Vietnamese rice has been studied to compare the As speciation in Sengcu rice from terraced paddies in mountainous terrain with commercial rice from lowland paddies. 53 The experimental conditions were determined by responsesurface methodology for optimal extraction of all As species by MAE and then HPLC-ICP-MS-MS for speciation. The method yielded 95% accuracy and <6.1% precision for the CRM material NIST SRM1568b rice ower.…”

“…92 The method consisted of sequential extraction/complexation of the two species: Cr III with EDTA and Cr VI with DPC (though the researchers consider that DPC reduces Cr VI to Cr III before complexation). Each sample (300 mg) was mixed with the 50 Cr III and 53 Cr VI spikes in a 50 mL polypropylene tube, and, as the equilibration of analytes and the corresponding spikes in the sample matrix is a critical step, the blended solution was thoroughly mixed by shaking for 10 min followed by standing for at least 15 min. Then, 16 mL of EDTA solution was added so that the nal concentration was 2.4 mmol L À1 and the mixture was maintained at 70 C (heating block) for 25 min.…”

Bis(catecholato)germane: an effective catalyst for Friedel–Crafts alkylation reaction

“…The isolated pure product was confirmed by NMR spectroscopy and mass spectrometry (see the ESI †) and verified with the reported data. [41][42][43][44] General procedure for the syntheses of nitroalkylated indoles β-Nitrostyrene (0.40 mmol) and indole (0.40 mmol) were added to a mixture of ethanol/water solvent mixture (2 : 1 v/v, 6 mL) followed by the addition of the complex 1 (0.040 mmol). The resulting clear solution was stirred at room temperature for 24 h. The progress of the reaction was checked by TLC.…”