High-resolution multi-temporal digital elevation model (DEM) are key to accurate mapping of gully erosion volume change studies. Owing to the lack of multi-temporal DEM at a high spatial resolution, gully development rate, and gully erosion-fill volume change estimates in the Indian badlands are poorly studied. Our study explored the use of multi-temporal TerraSAR-X add-on for digital elevation measurement (TanDEM-X) derived elevation models to quantify the erosion volume and gully susceptibility mapping in the Chambal badlands, Central India. The average volume of gully erosion based on the DEM subtraction method in the study area was found to be 135 Â 10 5 m 3 , and the estimated annual rate of soil erosion was $284 t hr À1 yr À1 . Using machine learning models, we trained these data for gully erosion susceptibilities and volume prediction for a larger study region; and validated the results with independent samples. The accuracy of the model in terms of area under the receiver operating curve (AUC) values has reached 0.85 for training and 0.87 for validation, indicating satisfactory model performance. After validation, the best fit model was implemented onto a testing site (no multi-temporal DEM available) in order to predict erosion zones and erosion volume estimation. The model predicted that about 40% of the area is highly affected by gully erosion, with the maximum gullying process in the north-Central and lowest in the southwest parts of the testing area. The research framework presented in this study can be useful in estimating the erosion rate in the badlands of the Chambal Valley and can be used effectively in ravine reclamation projects.

This study investigates different provisioning services in the peri-urban landscapes of Manila conurbation through a case study of two villages in the Jala-Jala municipality of the Laguna de Bay area in the Philippines. Laguna de Bay is an ecologically productive and important watershed for the urban and peri-urban areas of Manila for the provision of food, freshwater, and other materials. However, the lake and its ecosystem are under threat because of rapid urbanization and associated land-use changes. This study is based on a semi-quantitative survey conducted with 90 households in two villages: Special District and Paalaman. It was aimed to capture how provisioning services in the locality are connected with local livelihoods. The results obtained from the study suggest that landscapes in this peri-urban area still has considerable provisioning ecosystem services associated with local biodiversity and that this dependence on provisioning services and their relationship to peri-urban landscapes and biodiversity should be addressed for sustainable landscape management. The results have important implications for the conservation potential of biodiversity on which local livelihoods depend, in urban and peri-urban ecosystems.

Exotic organisms introduced into non-native ecosystems may invade and affect the native biodiversity, which might lead to serious ecological, economic and sociological threats. Among the various pathways of introduction of non-native species, on-line pet trading is the most recently emerging method which facilitates rapid introduction of exotic species. Though on-line trading has become an influential factor for the growth of world economy in the current scenario, its role in the introduction of exotic species and their subsequent consequences in countries like India is least studied. In this article we describe the role of on-line trading in importing alien species, which can cause serious threats to India's biodiversity and economy in near future. Our web survey revealed that 910 varieties of exotic fishes and 14 exotic animals are being sold through unregulated on-line trading. The number of exotic species recorded in this survey is not conclusive and may be the tip of the iceberg. Our interaction with the local people revealed that most of the sellers and buyers are naïve about the consequences of introducing these species into our native ecosystems. Most of the exotic fishes are maintained in open tanks and no regulations are being adopted to curtail their escape during maintenance of tanks, rains and floods. Greater abundance and biomass of Pterygoplichthys pardalis than the native edible fishes in freshwater ecosystem in Madurai is an example of invasion of ornamental fish into the wild. Bringing policy-level changes, multidimensional approaches to regulate on-line trade of exotic species will pave the way for protecting the native ecosystem from encroachment of exotic organisms.