# Promoting Urban Farming for Creating Sustainable Cities in Nepal
## 5 Empirical Analysis
### Estimated Avoidance of Greenhouse Gases by Urban Agriculture in Nepal  
Urban agriculture can help avoid emissions of greenhouse gases caused when traditionally produced agricultural products are transported to the urban markets. Obviously, the absorbed carbon dioxide will be changed into biomass and fruit production. [PERSON] et al. (2021) [50] and the World Bank (2019 and 2020) [51] estimated that it is possible to absorb 205 kg of CO\({}_{2}\)e per person from urban agriculture. Ninety (90%) of the plant biomass consists of carbon, hydrogen, and oxygen, and photosynthetically reduced carbon products (photoassimilates) are transported from \"sources, sites of production, to sinks, sites of growth and storage\" [52]. Using the allometric equations, it is possible to estimate the carbon use efficiency (CUE) of plants. However, in doing so, there are some uncertainties because the CUE may vary based on plants and the surrounding environment. Therefore, often variations are expected between 15 and 20% for aboveground biomass. For the belowground biomass, however, the estimation varies between 20 and 50% of the aboveground biomass [53] because herbaceous plant species sequester less carbon depending upon the types of compost used, and deep-root plants sequester carbon based on the depth of soils and other conditions of the soil and root depth penetration. Ph\(\%\) have concluded that the belowground biomass of plants is approximately 25% of the aboveground biomass; however, this may vary with rhizome plants [54] such as canna liliies, bearded iris, ginger and bamboo, and tuberous plants such as asparagus, airplane plant, dahlia, dayliliies, peonies, some irises, sweet potato, taro, and many others. The productivity of plants varies based on the CUE. Assuming a high CUE at 85% and low CUE at 80, the aboveground biomass of plants is presented in Table 6.  
The following calculation provides an estimate of the number of greenhouse gases that can be avoided by the practice of urban agriculture in Nepal. 1. Total urban population in Nepal is approximately 19 million (66% of 29 m) (CBS, 2021). 2. As an average household consists of 4.32 individuals, total no. of urban households is 19/4.32 = 4.4 million. 3. Around 10% of households may be doubling up in the dwellings; thus, the estimated urban number of dwelling units = 3.96 m.
4. Assuming 25% of the households live in multiunit complexes with limited balcony, rooftop, and ground spaces for farming, the total number of dwellings where urban farming is possible = 2.97 m (representing 12.8 m people) [50]. 5. Reference: 205 kg CO\({}_{2}\)e per person avoidance due to urban agriculture in Madrid [50]. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{2}{c}{**Aboveground Biomass**} & \multicolumn{2}{c}{**Belowground Biomass**} & \multirow{2}{*}{**Fruit**} \\ \cline{2-2} \cline{4-6}
**Plant Types** & \multicolumn{2}{c}{**(Tons)**} & & & **(Tons)** & \\ \cline{2-6} \cline{2-6}  & **Minimum** & **Maximum** & **Minimum** & **Maximum** & **CUE** & **Production** \\ \cline{2-6}  & **CUE** & **CUE** & **CUE** & **CUE** & **(Tons)** \\ \hline Rhizome & 209,920 & 223,040 & 52,480 & 55,760 & 104,960 \\ \hline Tuberous & 183,680 & 196,800 & 49,920 & 49,200 & 12,300 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Aboveground and belowground production at high (85%) and low (80%) CUE for rhizome and tuberous plants. Belowground biomasses are estimated at 25% of the aboveground biomass. Fruit production is estimated at 40% CUE for rhizome plants and 25% for tuberous plants. In Nepal, let us assume 20.5 kg CO\({}_{2}\)e per person avoidance (per capita/yr. emissions. This is based on the per-capita annual emission of 4.5 tons in Spain (2019), and for Nepal, 0.47 T (approx. 10% of Spain) (2019). 2. If all urban residents practiced urban agriculture in Nepal, the total annual CO\({}_{2}\)e avoidance = 262,400 T/yr. On average, a person consumes about 590 g (0.000591 metric tons) of vegetables or fruits in a day.