Explore the vast range of titles available.

Abstract Bioenergy is projected to have a prominent, valuable, and maybe essential, role in climate management. However, there is significant variation in projected bioenergy deployment results, as well as concerns about the potential environmental and social implications of supplying biomass. Bioenergy deployment projections are market equilibrium solutions from integrated modeling, yet little is known about the underlying modeling of the supply of biomass as a feedstock for energy use in these modeling frameworks. We undertake a novel diagnostic analysis with ten global models to elucidate, compare, and assess how biomass is supplied within the models used to inform long-run climate management. With experiments that isolate and reveal biomass supply modeling behavior and characteristics (costs, emissions, land use, market effects), we learn about biomass supply tendencies and differences. The insights provide a new level of modeling transparency and understanding of estimated global biomass supplies that informs evaluation of the potential for bioenergy in managing the climate and interpretation of integrated modeling. For each model, we characterize the potential distributions of global biomass supply across regions and feedstock types for increasing levels of quantity supplied, as well as some of the potential societal externalities of supplying biomass. We also evaluate the biomass supply implications of managing these externalities. Finally, we interpret biomass market results from integrated modeling in terms of our new understanding of biomass supply. Overall, we find little consensus between models on where biomass could be cost-effectively produced and the implications. We also reveal model specific biomass supply narratives, with results providing new insights into integrated modeling bioenergy outcomes and differences. The analysis finds that many integrated models are considering and managing emissions and land use externalities of supplying biomass and estimating that environmental and societal trade-offs in the form of land emissions, land conversion, and higher agricultural prices are cost-effective, and to some degree a reality of using biomass, to address climate change.

Since 1974, conservation efforts to protect an endangered species, the Golden Lion Tamarin (GLT), have led to the creation of the first strict nature reserve in Brazil ‒ the Poço das Antas Biological Reserve (REBIO) ‒ and the subsequent creation of the Environmental Protection Area of the Sao Joao River Basin, for sustainable use. This paper assesses the influence of Protected Areas (PA) creation and conservation programs on GLT habitat. Landscape metrics based on aerial photographs taken from three different periods are used to assess habitat conditions for this species through time. We analyzed the availability and potential quality of habitat in the years following the creation of the REBIO, comparing with its buffer zone and population rates correlations. We observed different trends in landscape dynamics between the REBIO, where most of the forest recovery occurred, and its buffer zone, where habitat loss was recorded. In general, the results showed an increase of continuous forest patches. The conservation/regeneration processes in the buffer zone have intensified in recent years. Comparisons over time, especially with respect to forest core areas and large patches, are valuable tools to assess landscape suitability for GLT survival at different spatial scales.

Based on land-use data collected every five years from 1990 to 2010, we quantified land-use dynamics and resultant effects on the ecosystem services along urban-rural gradients of the Guangzhou-Foshan Metropolitan Area, South China. The urban-rural gradients were set around the urban core cohesion zone with a 10-km-wide buffer zone and the value of each ecosystem service was calculated using a well-established benefit transfer method. The areas of construction land, water body and orchard expanded, while cropland, forestland and unused land contracted. The total value of ecosystem services decreased by US$ 200.33 million (or 4.3%) from 1990 to2010. Along the urbanrural gradients, the average value supplied by cropland, orchard and water body generally demonstrated a ‘first-rise-then-fall’ trend, while forestland and construction land presented an ever-increasing trend. For individual ecosystem services, raw material, gas regulation, climate regulation, soil formation and retention, biodiversity protection, recreation and culture increased steadily along the urban-rural gradients, while food production showed a fluctuating ‘first-rise-then-fall’ trend; water conservation and waste treatment increased fromthe core cohesion zone to the third concentric ring, and then had a sudden surge in the seventh concentric ring in both 2005 and 2010.

This study examines whether birds and butterflies may be used as surrogates for one another in assessing biodiversity at the community level. To do this, I compared the distribution and abundance of bird and butterfly species across an urban gradient by surveying six sites near Palo Alto, California, USA (all former oak woodlands) to see if these taxa have responded similarly to urbanization. The sites represent a gradient of urban land use ranging from relatively undisturbed to highly developed and include nature preserves, recreational areas, golf courses, residential neighborhoods, office parks, and business districts. At the community level, the two taxa displayed similar patterns across the gradient: species richness and Shannon diversity peak at intermediate levels of development, and the oak-woodland species gradually drop out at more developed sites. These measures are highly correlated between the two groups. The two taxa differed in their patterns of total abundance, however. Butterfly abundance was highest at the preserve and decreased as the sites became more urbanized, while bird abundance peaked at a site of intermediate development. These results suggest that, on spatial scales from 1 to 10 km, the two taxa display similar patterns with regard to urbanization and that one group can be used to infer the response of the other in assessing biodiversity with these measures at the community level.

Conversion of natural habitats into agricultural and industrial landscapes, and ultimately into degraded land, is the major impact of humans on the natural environment, posing a great threat to biodiversity. The emerging discipline of restoration ecology provides a powerful suite of tools for speeding the recovery of degraded lands. In doing so, restoration ecology provides a crucial complement to the establishment of nature reserves as a way of increasing land for the preservation of biodiversity. An integrated understanding of how human population growth and changes in agricultural practice interact with natural recovery processes and restoration ecology provides some hope for the future of the environment

Acid soils occupy approximately 30% or 3950 m ha of the world's ice free land area and occur mainly in two global belts where they have developed under udic or ustic moisture regimes. The northern belt (cold and temperate climate) is dominated by Spodosols, Alfisols, Inceptisols and Histosols and the southern tropical belt consists largely of Ultisols and Oxisols. Sixty-seven percent of the acid soils support forests and woodlands and approximately 18% are covered by savanna, prairie and steppe vegetation. Only 4.5% (179 m ha) of the acid soil area is used for arable crops. A further 33 m ha is utilized for perennial tropical crops. The value of the annual production in these areas is approximately US$ 129 billion. Value of products from forests, woodlands and permanent pastures on acid soils is difficult to evaluate. Forests of the tropics and wetlands have an invaluable role in global, regional and local ecosystem balance and a protective role for flora, fauna and water resources. While acid soils in the northern belt are increasingly protected and reafforested, the destructive exploitation of timber and abusive modern shifting cultivation have contributed to the loss of > 250 million ha of tropical forest during the second half of this century leaving vast areas of anthropic savannas on heavily eroded and degraded acid soils. The authors believe that attempts to develop acid soils for agriculture and agroforestry in the tropics should concentrate on these deforested and abandoned areas of degraded acid soils. However, this will be difficult without significant initial investment and adequate technology. A three step development approach is suggested, which could help prevent or halt the annual destruction of > 5 mill, ha tropical forests by \"untraditional shifting cultivators\". It would help to protect the fragile natural ecosystems on tropical acid soils now considered to be indispensable for the future life on earth.

Wild boar population size in the Iberian Peninsula was estimated using hunting bag statistics from Spain and Portugal. Density was estimated assigning the wild boar population size to the “potential resources” or suitable habitats categorized by their importance to provide food and/or shelter to wild boars. Land uses were selected from CORINE, the EU database for land cover, using scientific literature and statistical significance for wild boar presence from published data. The hunting bag was 176245 and 15167 in Spain and Portugal, respectively. The average density was 0.373/km2 (min 0.014-max 2.22) in Spain and 0.13/km2 (min 0.00048-max 1.99) in Portugal, being 0.31/km2 (0.00048-2.22) over the entire Peninsula. Statistical analysis showed that wild boar presence was significantly (p < 0.05) associated to thirteen of the seventeen CORINE land uses selected. Agro-forestry, moors and heathland land use were not statistically significant but were included in the model due to their biological importance. Suitable habitats and distribution of wild boar were mapped for the Iberian Peninsula. This approach is a preliminary step intended to be useful in environmental management and animal health.

Peatlands occupy a relatively small fraction of the Earth's land area, but they are a globally important carbon store because of their high carbon density. Undisturbed peatlands are currently a weak carbon sink (~0.1 Pg C y−1), a moderate source of methane (CH4; ~0.03 Pg CH4y−1), and a very weak source of nitrous oxide (N2O; ~0.00002 Pg N2O–N y−1). Anthropogenic disturbance, primarily agriculture and forestry drainage (10%–20% of global peatlands), results in net CO2emissions, reduced CH4emissions, and increased N2O emissions. This likely changes the global peatland greenhouse gas balance to a C source (~0.1 Pg C y−1), a 10% smaller CH4source, and a larger (but still small) N2O source (~0.0004 Pg N2O–N y−1). There is no strong evidence that peatlands significantly contributed to 20th century changes in the atmospheric burden of CO2, CH4, or N2O; will this picture change in the 21st century? A review of experimental and observational studies of peatland dynamics indicates that the main global change impacts on peatlands that may have significant climate impacts are (1) drainage, especially in the tropics; (2) widespread permafrost thaw; and (3) increased fire intensity and frequency as a result of drier climatic conditions and (or) drainage. Quantitative estimates of global change impacts are limited by the sparse field data (particularly in the tropics), the large variability present in existing data, uncertainties in the future trajectory of peatland use, interactive effects of individual impacts, and the unprecedented rates of climate change expected in the 21st century.

Livestock grazing is the most widespread land management practice in western North America. Seventy percent of the western United States is grazed, including wilderness areas, wildlife refuges, national forests, and even some national parks. The ecological costs of this nearly ubiquitous form of land use can be dramatic. Examples of such costs include loss of biodiversity; lowering of population densities for a wide variety of taxa; disruption of ecosystem functions, including nutrient cycling and succession; change in community organization; and change in the physical characteristics of both terrestrial and aquatic habitats. Because livestock congregate in riparian ecosystems, which are among the biologically richest habitats in arid and semiarid regions, the ecological costs of grazing are magnified in these sites. Range science has traditionally been laden with economic assumptions favoring resource use. Conservation biologists are encouraged to contribute to the ongoing social and scientific on grazing issues.

Forests occupy one third of the world’s land area and govern carbon (C) transfers and influence nitrogen (N) content in the biosphere. Afforestation leads to soil changes of specific dynamics, often accompanied by acidification. Especially at higher altitudes this effect is accelerated and increased with the stand age since forestation. The change in soil C and N content following afforestation is controlled by a number of factors, including: previous land use (grasslands, cropland, etc.), tree species, soil cultivation method, soil properties (clay content, pH), stand age, site management, topography, and climate. In the Czech Republic, large area changes in land use took place in the last centuries – forests covering roughly 20% in the 18th century currently occupy almost 34%, with still increasing tendencies. This paper compares basic soil properties (soil reaction, total soil organic carbon as well as total nitrogen contents) of the agricultural land and land afforested 40–60 years ago. The results confirmed the key role of afforestation in the change of soil organic matter dynamics after establishing new forests on the former agricultural lands in the uppermost mineral soil part of the Orlické hory Mts. region in the Czech Republic. During that time, comparatively substantial changes in soil organic matter and nitrogen were registered. Afforestation considerably increased organic matter content in the studied A-horizons of different land use types. Soil development resulted in a high production of C and N pools under the forest stands, contrary to agricultural land. In general, afforestation caused significant soil acidification. The common tendency of higher acidity of forest soils compared to agricultural ones was documented in the studied case as well. The general tendencies of soil reaction and soil organic matter dynamics at the studied sites are comparable to those in other regions of the Czech Republic.