Assessing the Contribution of Citrus Orchards in Climate Change Mitigation through Carbon Sequestration in Sargodha District, Pakistan

Muhammad Amjad Bashir,Ghulam Yasin,Aansa Rukya Saleem,Muhammad Farrakh Nawaz,Abdur Rehim,Ihsan Qadir,Muhammad Zubair,Zhenjie Du,Muhammad Ijaz,Sadaf Gul,Shafeeq Ur Rahman

doi:10.3390/su132212412

Abstract

Adopting agroforestry practices in many developing countries is essential to combat climate change and diversify farm incomes. This study investigated the above and below-ground biomass and soil carbon of a citrus-based intercropping system in six sites (subdivisions: Bhalwal, Kot Momin, Sahiwal, Sargodha, Shahpur and Silanwali) of District Sargodha, Southeast Pakistan. Tree biomass production and carbon were assessed by allometric equations through a non-destructive approach whereas, soil carbon was estimated at 0–15 cm and 15–30 cm depths. Above and below-ground biomass differed significantly, and the maximum mean values (16.61 Mg ha−1 & 4.82 Mg ha−1) were computed in Shahpur due to greater tree basal diameter. Tree carbon stock fluctuated from 6.98 Mg C ha−1 to 10.28 Mg C ha−1 among selected study sites. The surface soil (0–15 cm) had greater bulk density, organic carbon, and soil carbon stock than the subsoil (15–30 cm) in the whole study area. The total carbon stock of the ecosystem ranged from 25.07 Mg C ha−1 to 34.50 Mg C ha−1 across all study sites, respectively. The above findings enable us to better understand and predict the carbon storage potential of fruit-based agroforestry systems like citrus. Moreover, measuring carbon with simple techniques can produce trustworthy outcomes that enhance the participation of underdeveloped nations in several payment initiatives such as REDD+.

Highlights

The rapid increase of greenhouse gases has been responsible for severe global warming throughout the world in the last few decades [1]
The total biomass production of citrus trees ranged from 14.55 Mg ha−1 to 21.43 Mg ha−1 across six study sites with maximum accumulation at Shahpur and minimum at Sahiwal
The above and below-ground biomass accumulation varied significantly (p ≤ 0.05), and the distribution status of biomass amongst study sites was in the order of Shahpur > Sargodha > Silanwali > Bhalwal > Kot Momin

Summary

Introduction

The rapid increase of greenhouse gases has been responsible for severe global warming throughout the world in the last few decades [1]. Around 9.9 billion metric tons of CO2 have been deposited into the atmosphere annually, causing significant threats to the global environment [2]. According to Stocker [3], severe combustion of fossil fuels and land cover change are the leading anthropogenic causes of this higher CO2 content in the environment. Biomass is considered a vital carbon reservoir in the terrestrial ecosystem, playing a crucial role in the global carbon cycle [7]. Agroforestry is a well-managed system in which planting of woody trees is done along with crops on the same piece of land [11,12], is currently practised over more than one billion hectares in various parts of the globe and is acting as a major carbon sink around the world [13]. The carbon storage potential of various agroforestry systems is much inconsistent and ranges from 0.29 to 15.21 Mg ha−1 yr−1 around the globe [14]

Methods

Results

Conclusion