Predictive soil mapping (PSM) can be defined as the development of a numerical or statistical model of the relationship among environmental variables and soil properties, which is then applied to a geographic data base to create a predictive map. PSM is made possible by geocomputational technologies developed over the past few decades. For example, advances in geographic information science, digital terrain modeling, remote sensing, fuzzy logic has created a tremendous potential for improvement in the way that soil maps are produced. The State Factor soil-forming model, which was introduced to the western world by one of the early Presidents of the American Association of Geographers (C.F. Marbut), forms the theoretical basis of PSM. PSM research is being driven by a need to understand the role soil plays in the biophysical and biogeochemical functioning of the planet. Much research has been published on the subject in the last 20 years (mostly outside of geographic journals) and methods have varied widely from statistical approaches (including geostatistics) to more complex methods, such as decision tree analysis, and expert systems. A geographic perspective is needed because of the inherently geographic nature of PSM.

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The northern Ethiopian landscape is dotted with small patches of church forests that are religious centers for the Ethiopian Orthodox Tewahido Church (EOTC). These sacred groves are what remain of the once vast tropical Afromontane dry forest. Herein we review the landscape pattern of sacred groves in the Amhara region of Ethiopia, and their local scale nutrient status at two sites, Zahara and Debresena. A total of 1,488 sacred groves were inventoried within the study area, yielding an overall density of one sacred grove for every twenty square kilometers. Sacred groves averaged a little over five hectares and were separated from one another by more than two kilometers. At the local scale we found that soil carbon and nitrogen stocks have decreased significantly between the forest interior and the clearing indicating decreased soil fertility. Together our data indicate that these sacred groves are vulnerable to loss because of their small average size, isolation from seed sources, and decreasing soil status

Land-use change can have profound effects on forest communities, compromising seedling recruitment and growth, and long-term persistence of forests on the landscape. Continued forest conversion to agriculture causes forest fragmentation which decreases forest size, increases edge effects and forest isolation, all of which negatively impact forest health. These fragmentation effects are magnified by human use of forests, which can compromise the continued persistence of species in these forests and the ability of the forests to support the communities that depend on them. We examined the extent and influence of human disturbance (e.g. weedy taxa, native and exotic tree plantations, clearings, buildings) on the ecological status of sacred church forests in the northern highlands of South Gondar, Ethiopia and hypothesized that disturbance would have a negative effect. We found that disturbance was high across all forests (56%) and was negatively associated with tree species richness, density, and biomass and seedling richness and density. Contrary to expectation, we found that forests < 15.5 ha show no difference in disturbance level with distance from population center. Based on our findings, we recommend that local conservation strategies not only protect large forests, but also the small and highly used forests in South Gondar which are critical to the needs of local people, including preserving large trees for seed sources, removing exotic and weedy species from forests, and reducing clearings and trails within forests.

Land‐use change threatens biodiversity and ecosystem function worldwide. These changes have impacts on weather patterns, carbon storage, biodiversity, and other ecosystem services from regional to local scales. Only 8 percent of tropical forests are formally recognized as conservation areas, however globally, there is a network of sites that are protected because they are sacred and as a result act as ‘shadow’ conservation for biodiversity. Unlike other types of protected sites (e.g., national parks), these sites are seats of religious ritual that anchor a community's cultural identity, while also conserving biological diversity and other ecosystem services. We studied the extent and status of sacred forests in northern Ethiopia, which are threatened because of their small size (~5 ha) and isolation, increasing their exposure to edge effects and human pressures. Using historical and modern imagery, we found that over the last 50 yr, sacred forests have increased in area, but decreased in crown closure. We also found that forest ecological status, via ground‐level investigation, had high mean human disturbance (e.g., trails, plantations, exotic planting; 37%); and that forests close to markets (e.g., cities) increased in area due to planting of Eucalyptus (exotic), indicating a potential threat to their persistence and value as shelters of the church.

Church forests collectively represent the only surviving remnants of the original montane forest, serving as critical sanctuaries for many of Ethiopia's endangered and endemic plant and invertebrate taxa. Modern inventories of church forests suggest that they are vulnerable to degradation because of their small size and isolation. The aim of this study is to use historical air photos from the period of the Italian occupation of Ethiopia (1935–1941) to measure changes to church forests over a ~80‐year time span. We find little evidence that church forests in the study region around Debra Tabor in the northern Ethiopia highlands are declining in size. Rather, church forests have proven to be remarkably resilient on the landscape despite decades of dramatic change to the world around them. Our findings, therefore, highlight the effectiveness of religion‐based forest stewardship. Results also indicate, however, that while many church forests used to be buffered from intensive agricultural activity (e.g., cultivation and pasture) today, they find themselves significantly more isolated and vulnerable to edge effects as a result of a general decrease of trees and bushlands surrounding the forests. Copyright © 2016 John Wiley & Sons, Ltd.

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