ALBERT

Description: The Macapule Lagoon (25º 21' and 25º 24' N; 108º 30' and 108º 45' W) is part of the San Ignacio-Navachiste-Macapule lagoon system, located in the southern region of the Gulf of California (Fig. 1). In 2000, it has been declared an "Area of Reserve and Refuge for Migratory Birds and Wildlife – Gulf of California Islands". This lagoon is very productive due to its location in the Gulf of California (Lluch-Cota et al. 2007). Water temperature, dissolved oxygen, pH, and salinity were measured in situ with an YSI (55-12FT) probe and a portable refractometer (RHS-10ATC). Nutrient (nitrate, ammonium, and phosphate) concentrations were determined in the laboratory during each sampling month using a photometer (YSI, 9500).

Description: In December 2013, June and December 2014, and July 2015, a total of 123 specimens of L. argentiventris were captured in the Macapule Lagoon with gillnets of 50 mm mesh size. The total length and weight of each specimen were recorded. The liver, stomach, and gutted weight were weighed to the nearest gram (g) and the data used to calculate the following morpho-physiological indices: 1) the Fulton's condition factor (CF) using the equation: CF = W~t~/L~t~3 * 100, where W~t~ = total weight and L~t~ = total length; 2) the hepatosomatic index (HSI) using the equation: HSI = W~h~/W~t~*100, where W~h~ = liver weight and W~t~ = total weight of the individual; and 3) the gastric repletion index (GRI) using the equation GRI = W~s~/W~t~ *100, where W~s~ = stomach weight and W~t~ = total weight. Parameters of the length-weight relationship of L. argentiventris were estimated using the equation: W = aL^b^, where W = weight of the fish (g), L = total length (cm), a = y-intercept or the initial growth coefficient, b = slope or the growth coefficient. Blood samples of 1±0.1 mL were extracted (only of fish larger than 10 cm total length) by caudal puncture with a disposable plastic syringe containing 0.5 mL of heparinized solution (Sigma-Aldrich). The blood samples were centrifuged at 9,500 g at 4ºC during 10 minutes to separate the blood cells from the plasma. Total protein concentrations were determined following Bradford's method (1976), which is based on the reaction of the amino groups with the dye Coomassie Blue G-250. Triglycerides, glucose, and cholesterol concentrations were determined with colorimetric commercial kits Randox, U.K (Apún-Molina et al., 2015);. Absorbance was determined with a microplate reader (Multiskan Go, Thermo Scientific UV, United States) and concentrations were calculated from a standard solution of substrates.

Description: Mexico is the leading exporter of mangos worldwide, and ‘Ataulfo’ is one of the most popular cultivars. However, their production has dramatically dropped in recent years due to the high incidence of nubbins. One of the possible causes is the presence of a delayed self-incompatibility found in this cultivar; thus, proximity to compatible cultivars may help to reduce this incidence. Nevertheless, there is a lack of studies that have rigorously tested this hypothesis in this cultivar. For two consecutive years, the present study evaluated the incidence of nubbins, as well as the quality and quantity of commercial fruits of ‘Ataulfo’ trees located at 10, 30, and 50 m away from ‘Haden’ cultivar. Additionally, the yield and economic income of different planting designs were estimated. During both sampling periods, our results clearly indicated that at 10 m away from ‘Haden’ individuals, ‘Ataulfo’ trees presented a lower incidence of nubbins and higher production of commercial fruits, and higher yield and total income per hectare than at 30 or 50 m away from them. These results indicate that planting designs of ‘Ataulfo’ trees located 10 m away from ‘Haden’ will help to satisfy the increasing demand for mangos of this cultivar in the international market.

Description: In recent years, Multimetric Indices (MMIs) have received a lot of attention thanks to their ability to develop integrative evaluations of water quality, particularly in lagoons. In this article, we propose a new MMI for determining the water quality in lagoons. The proposed index is composed of biotic and abiotic indicators, in particular macroinvertebrates, macrophytes and morphological indicators. The proposed index is based on a geometric representation of a phenomenon associated with an ecological system, the ecosystem elements are mapped as vertices of a network and the relationship between them is represented by the corresponding edges. We classify the status of water bodies, from very low to very high using the ecological quality ratio. We compare our index with different different indices that measure water quality, such as General Biotic Index (JP(G)), Macrophyte Index for River (MIR) and Shannon diversity index (H’) and validate our index with Pearson’s correlation coefficient. A strong correlation with the JP(G) and MIR indices (R2 = 0.8605 and R2=0.7661, respectively) is obtained. Although the proposed index is composed of other indices, the independence of the proposed index with respect to its component indices is proven and the structure of the geometric model associated to the proposed network is studied. A close relationship between the measure called medium articulation and the geometric model associated with the proposed index is highlighted, which allows to determine the missing relationships in the network using structural analysis. The proposed index presents a more comprehensive measure than most indices currently used and has the advantage in the scalability, since other existing indicators can be integrated into our model.