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The extinction of a single species from a local community may carry little cost in terms of species diversity, yet its loss eliminates its biotic and abiotic interactions. We describe such a scenario in the Arava desert, where different cultural and law enforcement practices exclude Dorcas gazelles (Gazella dorcas (Linnaeus, 1758)) from the Jordanian side of the border while protecting their populations on the Israeli side. We found that gazelles break the soil crust, formed in desert systems after annual flooding, thereby creating patches of loose and cooler sand that are used by pit-building antlions (Neuroptera: Myrmeleontidae). When we artificially broke the soil crust on both sides of the border, we found a significant increase in antlion density in these patches, but only on the Israeli side. On the Jordanian side, where no gazelles have been observed since the early 1980s, no antlions colonized either control or manipulated plots. Additional choice/no-choice feeding experiments, in which we offered antlions to lizards and birds, revealed that the effect of humans on gazelles cascades farther, as antlions serve as a palatable food source for both groups. Thus, the human-mediated loss of nontrophic interactions between gazelles and antlions cascades to the loss of trophic interactions between antlions and their predators. Key words: ecological engineer, food web, Dorcas gazelle, Gazella dorcas, antlion, Neuroptera, Myrmeleontidae, desert. Si la disparition d'une seule espece dans une communaute locale n'est pas necessairement tres couteuse sur le plan la diversite specifique, la perte de cette espece elimine toutefois ses interactions biotiques et abiotiques. Nous decrivons un tel scenario dans le desert d'Arava, ou des pratiques culturelles et d'application de la loi divergentes excluent les gazelles dorcas (Gazella dorcas (Linnaeus, 1758)) du cote jordanien de la frontiere, mais en protegent les populations du cote israelien. Nous avons constate que les gazelles brisent la croute du sol, formee dans des systemes desertiques apres les crues annuelles, creant ainsi des parcelles de sable plus meuble et frais utilisees par des fourmilions (neuropteres : myrmeleontides) fouisseurs. Apres avoir brise artificiellement la croute du sol des deux cotes de la frontiere, nous avons note une augmentation significative de la densite de fourmilions dans ces parcelles, mais seulement du cote israelien. Du cote jordanien, ou aucune gazelle n'a ete observee depuis le debut des annees 1980, aucun fourmilion n'a colonise les parcelles temoins ni les parcelles manipulees. D'autres experiences d'alimentation dans lesquelles des fourmilions etaient offerts a des lezards et des oiseaux ont revele que l'effet des humains sur les gazelles se propage en cascade, puisque les fourmilions servent de source de nourriture attrayante pour les deux groupes. Ainsi, la disparition mediee par les humains d'interactions non trophiques entre les gazelles et les fourmilions se propage en cascade pour mener a la disparition d'interactions trophiques des fourmilions avec leurs predateurs. [Traduit par la Redaction] Mots-cles : ingenieur ecologique, reseau trophique, gazelle dorcas, Gazella dorcas, fourmilion, neuropteres, myrmeleontides, desert., Introduction The progression of species extinction draws considerable attention from the scientific world (Dirzo et al. 2014; Ceballos et al. 2015; Urban 2015;Jordano 2016;Tracewski et al. 2016)and has become one [...]

Offset schemes help avoid or revert habitat loss through protection of existing habitat (avoided deforestation), through the restoration of degraded areas (natural regrowth), or both. The spatial scale of an offset scheme may influence which of these 2 outcomes is favored and is an important aspect of the scheme's design. However, how spatial scale influences the trade‐offs between the preservation of existing habitat and restoration of degraded areas is poorly understood. We used the largest forest offset scheme in the world, which is part of the Brazilian Forest Code, to explore how implementation at different spatial scales may affect the outcome in terms of the area of avoided deforestation and area of regrowth. We employed a numerical simulation of trade between buyers (i.e., those who need to offset past deforestation) and sellers (i.e., landowners with exceeding native vegetation) in the Brazilian Amazon to estimate potential avoided deforestation and regrowth at different spatial scales of implementation. Allowing offsets over large spatial scales led to an area of avoided deforestation 12 times greater than regrowth, whereas restricting offsets to small spatial scales led to an area of regrowth twice as large as avoided deforestation. The greatest total area (avoided deforestation and regrowth combined) was conserved when the spatial scale of the scheme was small, especially in locations that were highly deforested. To maximize conservation gains from avoided deforestation and regrowth, the design of the Brazilian forest‐offset scheme should focus on restricting the spatial scale in which offsets occur. Such a strategy could help ensure conservation benefits are localized and promote the recovery of degraded areas in the most threatened forest landscapes. Article impact statement: Conservation offset schemes may yield greater additionality through avoided deforestation and restoration if implemented in smaller areas. [ABSTRACT FROM AUTHOR]

1. The ability to provide reliable projections for the current and future distribution of land- cover is fundamental if we wish to protect and manage our diminishing natural resources. Two inter- related revolutions make map productions feasible at unprecedented resolutions--the availability of high- resolution remotely sensed data and the development of machine- learning algorithms. However, ground- truthed data needed for training models is in most cases spatially and temporally clustered. Therefore, map production requires extrapolation of models from one place to another and the uncertainty cost of such extrapolation is rarely explored. In other words, the focus has mainly been on projections, and less on quantifying their reliability. 2. Using the concept of "forecast horizon", we suggest that the predictability of landcover classification models should be quantitatively explored as a continuum against distances measured along multiple dimensions--space, time, environmental and spectral. Focusing on ten agricultural sites from England and using models specifically designed to predict multivariate decay- curves, we ask: how does a model's predictive performance decay with distance? More specifically, we explored if we could predict the proficiency (kappa statistics) of a model trained in one site when making predictions in another site based on the spatial, temporal, spectral and environmental distances between sites. 3. We found that model proficiency decays with distance between sites in each dimension. More importantly, we found for the first time, that it is possible to predict the performance a model transferred to or from a novel site will have, based on its distances from known sites. The spectral distance variables were the most important when predicting model transferability. 4. Exploring model transferability as a continuum may have multiple usages including predicting uncertainty values in space and time, prioritisation of strategies for ground- truth data collection, and optimising model characteristics for defined tasks. [ABSTRACT FROM AUTHOR]