Pengaruh Tutupan Lahan Terhadap Fluks Co2 Pada Lahan Terbangun Dan Pertanian Di Tanah Inceptisol Dramaga

Abstract

Lahan pertanian yang dikelola secara intensif merupakan salah satu penyumbang emisi gas rumah kaca. Alih fungsi lahan dari pertanian ke kawasan terbangun berpotensi meningkatkan emisi CO2, khususnya pada tanah Inceptisol yang rentan terhadap gangguan. Penelitian ini bertujuan mengukur dan membandingkan fluks CO2 antara berbagai dosis pupuk hayati pada lahan pertanian dan fluks pada lahan terbangun, serta menganalisis pengaruh sifat kimia-biologi tanah terhadap fluks CO2. Penelitian dilaksanakan pada lahan pertanaman jagung di Kebun Percobaan Cikabayan, Dramaga, Bogor, mewakili satu siklus tanam pada Agustus 2025–Maret 2026. Fluks CO2 diukur setiap dua minggu menggunakan Infrared Gas Analyzer (IRGA) LI-COR 830. Pemberian pupuk hayati memengaruhi fluks CO2 pada lahan pertanaman jagung. Dosis 4 STD menghasilkan emisi CO2 kumulatif tertinggi selama periode pengamatan 0–10 MST, yaitu sebesar 38 Mg ha?¹. Fluks CO2 yang dihasilkan berfluktuasi pada setiap minggu setelah tanam (MST) dan cenderung meningkat seiring dengan bertambahnya dosis pupuk hayati serta setelah dilakukan aplikasi pupuk (P < 0,05). Secara umum, fluks CO2 pada lahan pertanian jagung lebih tinggi (26,5 Mg ha?¹ tahun?¹; P < 0,05) dibandingkan dengan lahan terbangun. Sementara itu, fluks CO2 pada lahan terbangun bagian luar lebih rendah (21 Mg ha?¹ tahun?¹; P < 0,05) dibandingkan dengan bagian dalam. Kandungan C-organik, P dan K potensial, serta total mikroba pada lahan pertanian lebih tinggi dibandingkan lahan terbangun bagian luar, tetapi masih lebih rendah dibandingkan lahan terbangun bagian dalam. Hubungan antara suhu udara maupun suhu tanah dengan fluks CO2 tergolong lemah (R² < 0,1). Secara keseluruhan, hasil penelitian ini menunjukkan adanya perbedaan karakteristik emisi CO2 antara lahan pertanian dan lahan terbangun, serta memperlihatkan bahwa pemberian pupuk hayati memengaruhi dinamika fluks CO2 pada lahan pertanaman jagung. Kata kunci: fluks CO2, inceptisol, lahan pertanian, lahan terbangun, pupuk hayati.

Intensively managed agricultural land is one of the major contributors to greenhouse gas emissions. Land use conversion from agricultural to built-up areas has the potential to increase CO2 emissions, particularly in Inceptisol soils, which are susceptible to disturbance. This study aimed to measure and compare CO2 fluxes under different biofertilizer application rates in agricultural land with those in built- up land, and to evaluate the influence of soil chemical and biological properties on CO2 fluxes. The study was conducted in a maize field at the Cikabayan Experimental Farm, Dramaga, Bogor, representing one growing season from August 2025 to March 2026. CO2 fluxes were measured every two weeks using a LI-COR 830 Infrared Gas Analyzer (IRGA). Biofertilizer application significantly affected CO2 fluxes in the maize field. The highest cumulative CO2 emission during the 0–10 weeks after planting (WAP) was observed at the 4 STD biofertilizer rate, reaching 38 Mg ha?¹. CO2 fluxes fluctuated throughout the observation period and generally increased with increasing biofertilizer rates and following fertilizer application (P < 0.05). Overall, CO2 fluxes from the maize field were significantly higher (26.5 Mg ha?¹ year?¹; P < 0.05) than those from the built-up land. In the built- up area, the outer section exhibited lower CO2 fluxes (21 Mg ha?¹ year?¹; P < 0.05) than the inner section. Soil organic carbon, potential phosphorus (P) and potassium (K), and total microbial populations in the agricultural land were higher than those in the outer built-up area but lower than those in the inner built-up area. Air temperature and soil temperature showed weak relationships with CO2 fluxes (R² < 0.1). Overall, the results indicate differences in CO2 emission characteristics between agricultural and built-up land and demonstrate that biofertilizer application influences the dynamics of CO2 fluxes in maize cultivation. Keywords: biofertilizer, built-up land, agricultural land, CO2 flux, inceptisol.