## 1 Introduction  
Mangrove forests cover approximately 13.7 million ha of tropical and subtropical shorelines across 118 countries [1]. Worldwide, Mexico ranks fourth in terms of mangrove coverage (742,000 ha), with 55% of the coverage distributed along the coast of the Yucatan Peninsula. Mangrove forests provide a wealth of direct and indirect ecosystem services such as natural protection barriers and nursery habitat for marine organisms [2; 3; 4; 5]. Further, the ability of mangrove forests to act as a carbon (C) sink has been the focus of recent research. Estimates suggest that mangrove C storage ranges between \(\sim\)160 Mg\(\cdot\)ha\({}^{-1}\) and \(\sim\)1000 Mg\(\cdot\)ha\({}^{-1}\) depending on location, species composition, height, and canopy closure [6; 7]. Data on C stocks have been published for numerous mangrove systems across the globe including Australia [6], China [8], Indo-Pacific [7; 9], Western-Pacific [10], Caribbean [11], and Mexico [12]. In addition, C removal from the atmosphere has been estimated at around 1,170 \(\pm\) 127 g\(\cdot\)C\(\cdot\)m\({}^{-2}\)\(\cdot\)year\({}^{-1}\)[13]. These figures acquire relevance in the context of climate change mitigation as C sequestration is emerging as a major strategy to reduce atmospheric C. In spite of the array of ecosystem services provided by mangroves, their high productivity, and their role played in C dynamics at the land-ocean interface [14], large areal losses are presently occurring due to deforestation and land use conversion due to both human and natural drivers [15; 16]. The high productivity and C uptake of mangroves are intimately linked to photosynthesis, which is largely dependent on the availability of leaf pigments. Chlorophylls (Chl) are the most important leaf pigments responsible for photosynthesis. Leaf pigments have been identified as indicators of physiological status, senescence and stress [17; 18]. This is also true in mangroves, which exhibit pigment variation between species and health conditions [19; 20; 21]. Furthermore, mangroves are subject to a range of environmental gradients that vary seasonally, potentially inducing stress. In a coastal lagoon system that was markedly seasonal in terms of water availability, [PERSON] and [PERSON] [21; 22] found higher Chl \(a\) concentration during the rainy season in two species of degraded dwarf stands, suggesting that precipitation patterns might have an effect on leaf biochemical constituents and possibly on the total productivity of the mangrove forest. Given the potential of Chl to act as a surrogate of vegetation status, Chl has become a key biophysical variable to monitor. The standard approach to estimating Chl concentration (CC) involves extracting the leaf pigment using an organic solvent followed by spectrophotometric determination of absorbance in the laboratory and, finally, conversion to CC using empirical equations [23, 24]. A more practical technique that complements the aforementioned approach consists on the use of portable Chl meters such as the Opti-Sciences CCM-200 Chlorophylll Content Meter (CCM-200) and Minolta SPAD-502 Chlorophylll Meter (SPAD-502). Portable Chl meters have been used extensively in precision agriculture and have been tested on a variety of tree species [25, 26, 27, 28, 29]. To our knowledge, the first documented example of the use a portable Chl meter in mangrove species is [PERSON] [30]. [PERSON] [30] reported a large correlation between CC and Minolta SPAD-502 readings in red mangrove (_Rhizophora mangle_) (_R\({}^{2}\)\(>\)_ 0.6 total Chl; _R\({}^{2}\)\(>\)_ 0.7 Chl _a_). Years later, [PERSON] [31] assessed the CCM-200 in _R. mangle_ (_R\({}^{2}\)\(>\)_ 0.9 Chl _a_) and other wetland species. Recently, [PERSON] and [PERSON] [32] documented large correlations for healthy stands of three mangrove species (_R. mangle R\({}^{2}\)\(>\)_ 0.76, _Laguncularia racemosa R\({}^{2}\)\(>\)_ 0.68 and _Avicennia germinans R\({}^{2}\)\(>\)_ 0.74; rainy season) using the CCM-200.