Department of Ecology and Environmental Science, Assam University, Silchar 788011, Assam, India.
Carbon Management and Sequestration Center, The Ohio State University, Columbus, OH 43210, USA.
Sci Total Environ. 2018 Sep 1;634:1024-1033. doi: 10.1016/j.scitotenv.2018.03.382. Epub 2018 Apr 11.
The "4 per Thousand" initiative was launched at the 21st Conference of Parties (COP21) in December 2015 to address global climate change through the aspirational goal of increasing soil organic carbon (SOC) stock of the world to 40-cm depth by an average annual rate of 4%. Small landholders (SLHs), often faced with difficult bio-physical and socio-economic conditions, are the principal managers of soil in India. There are 117 million SLHs representing 85% of the total operational holdings, cultivating over 72 million ha of land, and meeting 50-60% of India's food requirement. The agricultural soils of SLHs are strongly depleted of SOC and nutrient reserves. Therefore, the challenge of feeding 1.7 billion people in India by 2050 will depend on increasing the current productivity levels by restoring the depleted soils of SLHs. According to our estimates, soils of SLHs currently contain 1370-1770 Tg C and, which can be increased to 2460-2650 Tg C by 2050 through large-scale adoption of best management practices (BMPs) including balanced application of nutrients, compost, agroforestry, and conservation agriculture. A wide spread adoption of these practices can enhance C sequestration by 70-130 Tg COe per annum and produce 410-440 million Mg of food grains accounting for 80-85% of the total requirement by 2050. In this paper we propose strategies for achieving the dual objectives of advancing food security, the "4 per Thousand" target and mitigating climate change in India.
“千分之四倡议”于 2015 年 12 月在第 21 届缔约方大会（COP21）上启动，旨在通过将世界土壤有机碳（SOC）储量在 40 厘米深度内以每年 4%的平均速率增加的有抱负目标来应对全球气候变化。小土地所有者（SLHs），通常面临着困难的生物物理和社会经济条件，是印度土壤的主要管理者。有 1.17 亿 SLHs 代表了总运营持有量的 85%，耕种着超过 7200 万公顷的土地，满足了印度 50-60%的粮食需求。SLHs 的农业土壤强烈缺乏 SOC 和养分储备。因此，到 2050 年养活 17 亿印度人口的挑战将取决于通过恢复 SLHs 耗尽的土壤来提高当前的生产力水平。根据我们的估计，SLHs 的土壤目前含有 1370-1770TgC，可以通过大规模采用最佳管理实践（BMPs）将其增加到 2460-2650TgC，包括平衡施用养分、堆肥、农林复合经营和保护性农业。广泛采用这些做法可以每年增加 70-130TgCOe 的碳固存，并生产 4.10-4.40 亿吨粮食，到 2050 年占总需求的 80-85%。在本文中，我们提出了实现印度推进粮食安全、“千分之四倡议”目标和缓解气候变化双重目标的战略。
