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<p>Land ecosystems are important sources and sinks of atmospheric components. In turn, air pollutants affect the exchange rates of carbon and water fluxes between ecosystems and the atmosphere. However, these biogeochemical processes are usually not well presented in Earth system models, limiting the explorations of interactions between land ecosystems and air pollutants from regional to global scales. Here, we develop and validate the interactive Model for Air Pollution and Land Ecosystems (iMAPLE) by upgrading the Yale Interactive Terrestrial Biosphere Model with process-based water cycles, fire emissions, wetland methane (<span class="inline-formula">CH₄</span>) emissions, and trait-based ozone (<span class="inline-formula">O₃</span>) damage. Within iMAPLE, soil moisture and temperature are dynamically calculated based on the water and energy balance in soil layers. Fire emissions are dependent on dryness, lightning, population, and fuel load. Wetland <span class="inline-formula">CH₄</span> is produced but consumed through oxidation, ebullition, diffusion, and plant-mediated transport. The trait-based scheme unifies <span class="inline-formula">O₃</span> sensitivity of different plant functional types (PFTs) with the leaf mass per area. Validations show correlation coefficients (<span class="inline-formula"><i>R</i></span>) of 0.59–0.86 for gross primary productivity (GPP) and 0.57–0.84 for evapotranspiration (ET) across the six PFTs at 201 flux tower sites and yield an average <span class="inline-formula"><i>R</i></span> of 0.68 for <span class="inline-formula">CH₄</span> emissions at 44 sites. Simulated soil moisture and temperature match reanalysis data with high <span class="inline-formula"><i>R</i></span> above 0.86 and low normalized mean biases (NMBs) within 7 %, leading to reasonable simulations of global GPP (<span class="inline-formula"><i>R</i>=0.92</span>, <span class="inline-formula">NMB=1.3</span> %) and ET (<span class="inline-formula"><i>R</i>=0.93</span>, <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M12" display="inline" overflow="scroll" dspmath="mathml"><mrow><mtext>NMB</mtext><mo>=</mo><mo>-</mo><mn mathvariant="normal">10.4</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="68pt" height="10pt" class="svg-formula" dspmath="mathimg" md5hash="f52780d12f23d93821e5206b56807826"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gmd-17-4621-2024-ie00001.svg" width="68pt" height="10pt" src="gmd-17-4621-2024-ie00001.png"/></svg:svg></span></span> %) against satellite-based observations for 2001–2013. The model predicts an annual global area burned of 507.1 Mha, close to the observations of 475.4 Mha with a spatial <span class="inline-formula"><i>R</i></span> of 0.66 for 1997–2016. The wetland <span class="inline-formula">CH₄</span> emissions are estimated to be 153.45 <span class="inline-formula">Tg [CH₄] yr⁻¹</span> during 2000–2014, close to the multi-model mean of 148 <span class="inline-formula">Tg [CH₄] yr⁻¹</span>. The model also shows reasonable responses of GPP and ET to the changes in diffuse radiation and yields mean <span class="inline-formula">O₃</span> damage of 2.9 % to global GPP. iMAPLE provides an advanced tool for studying the interactions between land ecosystems and air pollutants.</p>