Mapping community change in modified landscapes

Habitat loss is not randomly distributed across modified landscapes, yet spatial patterns of habitat cover are not routinely combined with biodiversity data when assessing or predicting the biodiversity impacts of land use change. Here, we convert point observations of more than 28,000 beetles from 851 species into a continuous biodiversity surface representing the similarity of ecological communities relative to that of pristine forest, effectively integrating on-the-ground biodiversity data with remotely sensed land cover data to predict the magnitude of community change in a modified landscape. We generated biodiversity surfaces for both present-day and pre-human landscapes to map spatial patterns of change in a diverse ecological community to calculate the combined biodiversity impacts of habitat loss and fragmentation that accounts for the exact spatial pattern of deforestation. Our spatially-explicit, landscape-scale index of community change shows how the fine-scale configuration of habitat loss sums across a landscape to determine changes in biodiversity at a larger spatial scale. After accounting for naturally occurring within-forest heterogeneity, we estimate that the conversion of 43% of forest to grassland in a 1300 km² landscape in New Zealand resulted in a 47% change to the beetle community.     

Global analysis of the protection status of the world’s forests

This study presents a global analysis of forest cover and forest protection. An updated Global Forest Map (using MODIS2005) provided a current assessment of forest cover within 20 natural forest types. This map was overlaid onto WWF realms and ecoregions to gain additional biogeographic information on forest distribution. Using the 2008 World Database on Protected Areas, percentage forest cover protection was calculated globally, within forest types, realms and ecoregions, and within selected areas of global conservation importance. At the 10% tree cover threshold, global forest cover was 39 million km². Of this, 7.7% fell within protected areas under IUCN management categories I–IV. With the inclusion of IUCN categories V and VI, the level of global forest protection increased to 13.5%. Percentage forest protection (IUCN I–IV) varied greatly between realms from 5.5% (Palearctic) to 13.4% (Australasia), and for forest types from 3.2% (temperate freshwater swamp forest) to 28% (temperate broadleaf evergreen forest). Median protection of forest cover in 670 ecoregions (forest above a specified threshold) was 5.9% (IUCN I–IV); at IUCN I–VI, 46% of the ecoregions had less than 10% forest protection. Considering their biodiversity importance, forest protection within global priority areas was insufficient, e.g., median protection of 8.4% in biodiversity hotspots (IUCN I–IV). Results have policy relevance in terms of the target of the Convention on Biological Diversity (CBD), reconfirmed in 2008, to effectively conserve “at least 10% of each of the world’s forest types”. Regular updates of these analyses would allow progress towards achieving that target to be monitored.     

Morphological reproductive characteristics of testes and fertilization capacity of cryopreserved sperm after the Fukushima accident in raccoon (Procyon lotor)

Since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, we have established an archive system of livestock and wild animals from the surrounding ex-evacuation zone. Wildlife within the alert zone have been exposed to low-dose-rate (LDR) radiation for a long continuous time. In this study, we analysed the morphological characteristics of the testes and in vitro fertilization (IVF) capacity of cryopreserved sperm of racoons from the ex-evacuation zone of the FDNPP accident. The radioactivity of caesium-137 (¹³⁷Cs) was measured by gamma-ray spectrometry, and the measured radioactivity concentration was 300–6,630 Bq/kg in the Fukushima raccoons. Notably, normal spermatogenesis was observed in the seminiferous tubules of the testes, with the germinal epithelium composed of a spermatogenic cell lineage with no evident ultrastructural alterations; freeze-thawing sperm penetration ability was confirmed using the interspecific zona pellucida-free mouse oocytes IVF assays. This study revealed that the chronic and LDR radiation exposure associated with the FDNPP accident had no adverse effect on the reproductive characteristics and functions of male raccoons.     

Bringing Southeast Asia to the Southeast United States: New forms of alternative agriculture in Homestead,Florida

Immigrant farmers from Southeast Asia have brought knowledge of tropical fruit and vegetable production from their home countries to Homestead, Florida. They have developed a new style of farming, one that most closely resembles agricultural systems described as “homegardens.” Although biodiverse agricultural systems are generally thought to be commercially unviable, homegarden farmers successfully manage crop diversity as an economic strategy. By focusing on growing a mixture of specialty Southeast Asian herbs, fruits, and vegetables, the farmers have created their own economic niche and have shielded themselves from the competition of high-volume, single commodity producers. This paper shows that the Homestead homegardens constitute an alternative form of agriculture that is defined by their agroecological and socioeconomic attributes. It also shows that although the homegarden farms are a form of “alternative agriculture,” they do not operate outside of conventional, global systems of agricultural trade; rather the homegarden farms are embedded in global agriculture. The Homestead case problematizes the tendency to delineate between the global and local scales, and alternative and conventional sectors in agriculture today. This paper concludes that the emergence of the Homestead homegardens can only be understood by taking a place-based approach to studying the environment in which the homegardens are situated as well as identifying the large-scale influences on Miami-Dade County. Valerie Imbruce holds a PhD in plant sciences from a joint program between the Graduate Center of the City University of New York and the New York Botanical Garden. She has conducted research on global agricultural systems in New York City, south Florida, and Central Honduras.     

2500 years of European climate variability and human susceptibility

Climate variations influenced the agricultural productivity, health risk, and conflict level of preindustrial societies. Discrimination between environmental and anthropogenic impacts on past civilizations, however, remains difficult because of the paucity of high-resolution paleoclimatic evidence. We present tree ring-based reconstructions of central European summer precipitation and temperature variability over the past 2500 years. Recent warming is unprecedented, but modern hydroclimatic variations may have at times been exceeded in magnitude and duration. Wet and warm summers occurred during periods of Roman and medieval prosperity. Increased climate variability from ~250 to 600 C.E. coincided with the demise of the western Roman Empire and the turmoil of the Migration Period. Such historical data may provide a basis for counteracting the recent political and fiscal reluctance to mitigate projected climate change.