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• We propose a new methodology for measuring and evaluating the environmental performance of logistics systems. • Value-added concept is used to classifies the consumption and waste processes of urban freight transportation systems. • Our methodology uses the Overall Greenness Performance (OGP) tool with a mixed-integer linear programming (MILP) model. • The approach is validated through a case study from a company in Colombia. Environmental sustainability is a requirement for modern urban freight transport systems. On a global scale, most resources are currently consumed in cities, contributing to the economic importance of urban freight transport as well as its poor environmental performance. However, there is a lack of knowledge about how to correctly quantify the environmental efficiency of urban freight systems. In this context, this paper proposes a new methodology for evaluating the environmental performance of urban freight transport systems by applying the Overall Greenness Performance (OGP) tool. OGP is a lean-based hierarchy of metrics that uses the value-added concept to relate a company's productivity with its environmental performance. The proposed methodology uses a mixed-integer linear programming model to assess the environmental impact of the activities and/or requirements in an urban freight transportation system. This paper examines how company context, the supply chain and value stream activity types, namely value adding, necessary but non-value adding and non-value adding, affect a system's performance, operational costs and environmental impact. Real data from the city of Bogotá, Colombia, were used to validate this approach. A sensitivity analysis was performed with different companies, demands and costs in order to evaluate the trade-offs between economic performance and environmental impact. [ABSTRACT FROM AUTHOR]

• Abundance and richness differences were observed between tourism areas. • All areas maintained a homogeneous beetle structure in terms of functional groups. • Dung beetle assemblage loss particular species by the pressure of tourism. • It is essential to implement conservation strategies to reduce impact of tourism. Ecotourism can be defined as an environmental activity that takes place in well-preserved areas for recreation and with the responsibility of promoting their conservation. Nowadays, ecotourism is seen as a friendly pastime, but it can potentially affect negatively community diversity and structure by a number of processes such as soil compaction, erosion, and habitat alteration, among many others. Nonetheless, there is hardly any information on the impact of ecotourism in the Tropical Dry Forests and protected areas of the Neotropical region. In an attempt to fill this knowledge gap, the effect of ecotourism was evaluated in a study of a Tropical Dry Forest in the Tayrona National Natural Park of Colombia using dung beetles as bioindicators. A large-scale sampling of three sites with different levels of tourism intensity (no tourism – NT, low tourism – LT, and high tourism – HT) was performed using pitfall tramps baited with human/pig dung during two climatic seasons (rainy and dry). A total of 3238 individuals belonging to nine genera and 15 species were collected. Significant differences in abundances, richness, and the Shannon Wiener diversity index were observed between areas with tourism and those without. These differences disappeared during the dry season in response to the strong reduction in species abundance and richness associated to that time of year. All areas maintained a homogeneous beetle structure in terms of functional groups present irrelevant of the intensity level of tourism. Beta diversity analysis shows that the dung beetle assemblage has a nested structure, indicating that the pressure exerted by tourism entails the loss of particular species. Our results advocate that it is necessary to implement conservation strategies in order to reduce the negative impact of tourism on the National Park's biodiversity. [ABSTRACT FROM AUTHOR]