El presente trabajo se realizó en el ejido las coloradas, Cárdenas, Tabasco, con el objetivo de cuantificar el volumen maderable del mangle negro (Avicennia germinans (L.) L., afectado y muerto por la oruga de Anacamptodes sp., durante 2010-2011. Se establecieron 10 unidades de muestreo (UM) de forma rectangular de 20 x 50 m para evaluación permanente. Se registró el estado sanitario de los árboles, el diámetro a la altura del pecho (DAP 13 m), la altura total y altura del fuste limpio (Ht y Hfl). Se calculó el área basal (AB m2ha-1), Volumen total y del fuste limpio (Vt y Vfl m3ha-1) y se estimó la densidad de árboles por especie. Los valores obtenidos se arreglaron en clases diamétricas con una amplitud de 5 cm. Se realizó un análisis de correlación lineal simple entre la altura y el DAP. En total se evaluaron 1,831 árboles de tres especies, tres géneros y tres familias botánicas. El mangle negro representó 99.6% del total de árboles evaluados; la densidad varió de 750 hasta 2,520 árboles por ha-1. El 42.9% de los árboles registrados mostraban partes vivas y el 57.1% estaban totalmente muertos. Específicamente, el mangle negro registró un Vt de 68.3 m3 ha-1, Vfl de 24.6 m3 ha-1y un AB de 12.4 m2 ha-1. La categoría de 5 - 9.9 cm de DAP registró el 45% de los árboles identificados. La correlación del DAP y la altura del mangle negro, fue moderada positiva significativa (r² = 0.5313, p = 2.2 e-16).Rev. iberoam. bioecon. cambio clim. Vol.1(1) 2015; 115-133

described, and the importance value (IVI) and the modified forest value (IVFm) indices were calculated. Diversity was analyzed using indices of Shannon-Wiener (H'), Simpson (S) importance and forest values Haematoxylum campechianum L. in SBSP, Clusia salvinii Donn Sm. in SMP and Brosimum alicastrum Sw. in SAP. Three vertical layers were identified: below (< 4 m; < 5 m), medium (4 to 9 m; 5 to 8 m) and upper (> 8 m; > 9 m up to 25 and 38 m) in the SMP and SAP, in the SBSP a single layer (12 m) was found. Diversity of tree species was significantly (p < 0.01) higher in SAP (H' = 3.21) compared to SMP (H' = 2.19) and SBSP (H' = 0.91). Floristic similarity among UM was higher in SBSP (IS = 58.5 to 79.9%) compared to SAP (23.5 to 48.1%) and SMP (1.1 to 35%). In this study the major species and the floristic composition for each tropical forest are recognized, which is expected to be useful in future research and thus contribute to define conservation, reproduction and sustainable use strategies of these tropical forests.

For Spanish cedar (Cedrelaodorata L., Meliaceae) is unknown if big fruits contain a greater number of seeds and if those seeds have better physic and biological quality than those coming from small fruits. Therefore, the relation between physic characteristics of fruit and seed with Spanish cedar germination was determined. One hundred seeds per tree from three groups of 12 trees were sown in individual nursery bags and 100 in a seedbed. Fruit weight and number of seeds per fruit differed significantly among the three groups of trees. Fruit size was directly related to seed weight and inversely related to number of seeds per fruit.Germination in nursery bags did not correlate neither to fruit nor seed variables, but correlated in seedbed (r = 0.99, P = 0.03) to both fruit weight and number of seeds per fruit. The conclusion is that weightier fruits correspond to higher number of seed per fruit, smaller seeds and higher germination in Spanish cedar which would be useful to sure the plant production in nurseries.

Objective: The aim of this study was to characterize Spanish cedar (Cedrela odorata L.) fruits and seeds, and to evaluate the effects of provenance, substrata, and fertilizer on germination and plant quality in nursery. Design/Methodology/Approach: The fruits and seeds from Spanish cedars were collected in three different towns: C-32 (Francisco Trujillo Gurria), C-40 (Ernesto Aguirre Colorado), and C-41 (Carlos A. Madrazo). Those towns are in Plan Chontalpa, Tabasco, Mexico. After they were harvested, the samples were morphometrically characterized. Seed production efficiency (SPE), germination (%), and Dickson Quality Index (DQI) were estimated. Two completely randomized experimental designs with factorial arrangement of treatments were used. The factors were the provenance, four or three substrata, and two levels of Greenfool® 600 fertilizer. Results: Fruits of 3.46 cm in length and 1.81 cm in width were collected; the mean number of seeds per fruit was 49.36. Seed production efficiency ranged from 48.1% to 52.72%, with 32.86% germination. The seeds from Town C-41 obtained the highest germination percentage, with the use of black soil:sand as substrate. The plants fertilized and developed in black soil:sand substrate obtained a higher DQI. Study Limitations/Implications: The activity restriction caused by the Sars-Cov-2 pandemic was the main limitation. The lower number of producers and plantations from Town C-32 was the implication. Findings/Conclusions: Fruit and seed characteristics were different among provenances. The provenance impacted on seed germination, but not on the plant quality index (DQI). Instead, the substrate and fertilizer impacted on the DQI.