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Copyright of Ecosistemas y Recursos Agropecuarios is the property of Universidad Juarez Autonoma de Tabasco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Epiedaphic springtails participate in a wide variety of services linked to plant nutrient availability, water storage and regulation, soil stability and control of moisture and pH necessary for soil fertility. Therefore, epiedaphic springtails are sensitive to soil use change. Objective: To compare diversity of epiedaphic springtails in two types of introduced vegetation: pastures and forestations of Eucalyptus pellita in a region of the Colombian eastern plans. Methods: Springtails were collected from introduced pastures and young, middle and mature forested areas of E. pellita, using pitfall traps containing Propylene Glycol (40%) as preservative, during one dry and one wet season. Alfa and Beta diversity were compared at genus level, and community composition was explained using a set of 14 environmental variables through a redundancy analysis (RDA). Results: Epiedaphic springtails were represented by Entomobryomorpha (62%), Poduromorpha (17%) and Symphypleona (21.1%), 12 families and 26 genera. Effective number of Collembola genera was lower in plantations but abundance was different only in young plantations during dry season. The variables related to forest coverage, soil organic matter coverage and Nitrogen better explained the observed genera assemblage. Conclusions: Forest plantations allowed an assembly of springtails less diverse than in pastures; but comprised both types of genera, those proper of open areas and those from surrounding natural wooded areas. [ABSTRACT FROM AUTHOR]

The diversity of macro-invertebrates is related to the state of disturbance of the soil, caused mainly by the land-use change for agricultural activities. A strategy for the conservation of these organisms is the implementation of diversified production systems such as silvopastoral systems. However, in the Southeast of Mexico, information is still limited. The aim of the present study was to evaluate and compare the richness, abundance and composition of macro-invertebrates in four contrasting agro-ecosystems: two silvopastoral systems made of Leucaena leucocephala and associated pastures (i.e. Panicum maximum cv mombaza and Cynodon plectostachyus), a pasture of Brachiaria brizantha with scattered trees in low density and, a medium-statured tropical dry forest. In each system, an area of one hectare was delimited and a transect of 50 m in length was established in which five pit-fall traps were placed every 10 m. The sampling was carried out in February and May of 2018 and in each month five collections were made with five-day intervals. A total of 1 737 organisms belonging to 10 orders of the class Insecta and one of the class Gastropoda were collected. The medium-statured tropical dry forest (923 individuals) and the silvopastoral systems of L. leucocephala with C. Plectostachyus (354 individuals) show the highest abundance of macro-invertebrates. The most abundant genera were: Hymenoptera, Coleoptera, Aracninae and Orthoptera. The higher macro-invertebrate diversity was found in the silvopastoral systems of L. leucocephala with P. maximum (H '= 1.58) and L. leucocephala with C. plectostachyus (H' = 1.44). The results show that livestock systems managed with woody components (trees or shrubs) are home of an important abundance and richness of macro-invertebrates, compared to tropical forests. This diversity of macro-invertebrates may contribute to the integrity and functionality of the agro-ecosystems. [ABSTRACT FROM AUTHOR]

This study was completed under edaphoclimatic conditions in Camagüey during one year. The objective was to determine the carbon retention and the soil fauna associated with Moringa oleifera Lam, used for living fences, specifically a one-year-old fence, built on a typical brown soil without carbonate. The approximate carbon sequestration and the soil fauna associated with the species were calculated. The results indicated the advantages of using M. oleifera L. for living fences, due to their positive environmental effect when sequestring high levels of carbon dioxide (the carbon stored by this species is of 68 kg/a, which is closely equal to 45,35 t of C/km), and they also create a favorable environment for soil fauna. In the assessed period, the worms and the coleopterons were the main groups found, which are also important for maintaning a healthy ecosystem. [ABSTRACT FROM AUTHOR]

The conservation status of soils with different uses was characterized using the taxonomic and trophic composition of the edaphic mesofauna. The research was conducted during the rainy season of 2009 in 11 sites selected under four general classes of land use (GCLU): regenerated forests, pasturelands, sugarcane plantations and varied crops (mainly potatoes). Three soil samples were taken in each land use replication, at only one depth level (0-10 cm), following a stratified completely randomized sampling design. For the extraction Berlese-Tullgren funnels were used, with a source of light and heat, during seven days. The highest values of taxonomic composition of these soil micro arthropods were found in the forests, with 16 families, followed by pasturelands with nine families, varied crops and sugarcane plantations with six families each. On the other hand, the largest representation of detritivorous groups appeared in the forest with four orders, 15 families and 151 individuals, followed by varied crops with two orders, five families and 62 individuals, and pasturelands with two orders, eight families and 37 individuals; while in sugarcane plantations fungivores were the best represented by an order and 22 individuals. The taxonomic and trophic composition of the groups that integrate the edaphic mesofauna indicated the soil degradation status in the order sugarcane plantation-varied crops, followed by pastureland and, finally, forest. [ABSTRACT FROM AUTHOR]

The study assessed the effect of the intensity of different land uses (secondary forests, pasturelands, fields with varied crop cultivation dedicated to potato production and sugarcane plantations) on the richness and abundance of soil macro fauna communities. The research was conducted in October, at the end of the rainy season, 2009, in the Artemisa and Mayabeque provinces where the different land use systems are located. The soil macro fauna was collected using the methodology proposed by the TSBF program. The taxonomic richness, density and biomass of soil macro fauna were evaluated and the data processing included nonparametric tests. The highest values of richness, density and biomass were obtained in the secondary forests and the lowest values in the pasturelands, varied crop cultivation and sugarcane plantations. Haplotaxida, Formicidae, Isoptera, Coleoptera and Diplopoda were the prevailing taxonomic units of the macro fauna regarding density and biomass in most of the land uses. The results about taxonomic richness, density and biomass of the edaphic macro fauna indicated the degree of soil degradation due to land use intensity. [ABSTRACT FROM AUTHOR]

In the Coffee Belt of Colombia we studied different patterns in land use considering the interaction between abundance, diversity and biomass of soil invertebrates (millipedes, beetles and earthworms), some physicochemical variables and land use intensity. Highest abundance and biomass of Coleoptera were found in Eucalyptus-lulo (Solanum quitoense), with 48 ind. m-2 and 9.4 g fresh weight (gfw) m-2, respectively. Millipede abundance and biomass was higher in the relict forest (53 ind. m-2 and 4.8 gfw m-2, respectively) and in the coffee variety "Colombia" (39.4 ind. m-2 and 3.1 gfw m-2, respectively). Earthworm abundance was higher in Eucalyptus-lulo (768 ind. m-2) and in the coffee variety Colombia (540 ind. m-2). Biological and physicochemical variables permitted the differentiation of three and four land use patterns, respectively. When they were combined with coinertia analysis, three patterns were distinguished, related to soil moisture, C and N contents and bulk density (p < 0.02). In pastures and the coffee variety Colombia, beetles (Ataenius sp., Onthophagus atriglabrus, Dichotomius satanas) and peregrine earthworms were dominant (Pontoscolex corethrurus, Polypheretima elongata, Dichogaster annae, Perionyx excavatus), soil C and N contents were low and bulk density higher. The analysis showed potential for separating biodiversity-friendly or biodiversity-critical areas and may be useful for land use planning in rural areas. [ABSTRACT FROM AUTHOR]

Soil-inhabiting invertebrates play an important role in soil processes. Soil fauna include organisms of diverse sizes and adaptive strategies. Macrofauna, large organisms with body width greater than 2 mm, influence soil properties, both directly and indirectly. Their communities are influenced by soil management and thus, have a great potential as bioindicators. The objective of this study was to evaluate the effect of different crop-pasture rotations on soil macrofauna. Treatments included continuous agriculture without (S1) and with (S2) fertilization, 33% crop - 66% pasture rotation (S4), 50% croppasture rotation (S5), and 66% crop - 33% pasture rotation (S7). The number of organisms collected varied with land use intensity; treatments S1 and S4 had the lowest and highest population densities for most taxa, respectively. The Co-Inertia analysis between soil properties and population density was significant. The first axis ordered land uses in relation to its intensity. Oligochaeta and Coleoptera adults were associated with S4, the system with highest organic carbon and total nitrogen contents. The evaluation of soil macrofauna together with soil properties is a useful tool to assess land use sustainability. [ABSTRACT FROM AUTHOR]

The aim of this work was to determine the taxonomic composition and relative abundance of the soil meso and macrofauna and their different trophic groups as affected by soil management practices. Four cropping systems were evaluated: LC50 [(50% pasture - 50% cropping under conventional tillage (LC)], SD50 [(50% pasture - 50% cropping under no-tillage (SD)], LC75 (25% pasture - 75% cropping under LC), SD75 (25% pasture - 75% cropping under SD). In the year 2000, a pasture (P) was sown on LC50 and SD50 and in 2001 it was one year old. On LC75 and SD75, corn was planted in 2000 and soybean was planted in 2001. Most of the individuals observed in 2000 within the mesofauna were enchytraeids and their abundance was not different between LC and SD, whereas in 2001 the highest abundance of enchytraeids was observed under the 15-year-old P. Within the macrofauna, earthworms, isopods and miriapods predominated, but isopods and miriapods were dominant under P in both years. In the first year, the meso and macrofauna densities were not significantly different (p>0.003) among cropping systems, although they tended to be greater under SD. In the second year, such densities were significantly higher (p<0.003) under P. In both years, density interactions between cropping systems and fertilization rates were not significant (p>0.003) for detritivours, herbivours, predators and omnivous. Despite the lack of significant differences (p>0.003) among systems during the first year, all four trophic groups were more abundant under P and SD than under LC. In the second year, detritivours, predators, and omnivours were significantly more abundant under P than under soybean. Our results confirm that the cropping systems affected the taxonomic composition of the soil meso and macrofauna and their trophic groups. On the other hand, the abundance of both communities increased under P throughout the experiment. [ABSTRACT FROM AUTHOR]

Soil organisms have an essential role in the processes of humification, decomposing and structuring; consequently several toxicological studies have been carried out to determine the impact of insecticides on them, principally in laboratory with individual species. Regrettably, there are few field assays. The objective of this research was to determine the effect caused by the insecticide imidacloprid on soil organisms when it was applied to peach trees (Prunus persica (L.) Batsch) var. Red Globe. The control treatment (without chemicals) managed with yellow and pheromone traps was compared with treated plots in which the insecticide was applied to the soil and leaves, using two different concentrations for each treatment (0.5 and 10 cm³ L-1). A litter bag assay was carried out in order to determine the impact of the insecticide. Polyethylene bags with two different mesh sizes full of dry alfalfa (Medicago sativa L.) were buried. The distinct mesh sizes permitted the entrance of different organisms, achieving a stratification of the acting species. At five months, the bags were removed and the dry matter weight was analyzed. The experimental design was a split plot and the combination of factors produced eighteen treatments with three replicates. The results were analyzed using ANOVA. There were no significant differences between soil and canopy treatments and control (6, 5.92 and 5.83 g DM, respectively), nor between concentrations. The decomposition of organic matter was greater (p < 0.05) in the buried bags with bigger mesh size (6.38 g DM) than the smaller mesh size (5.45 g DM) probably due to a greater activity of the soil macrofauna. [ABSTRACT FROM AUTHOR]