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Columbian sharp‐tailed grouse (Tympanuchus phasianellus columbianus) are endemic to grassland and shrub‐steppe ecosystems of western North America, yet their distribution has contracted to <10% of their historical range. Primary threats to Columbian sharp‐tailed grouse include loss of native habitat and conversion to agriculture, reductions in habitat once provided by the Conservation Reserve Program (CRP), wildfire, and drought conditions, yet population‐level consequences of these threats and their spatio‐temporal scales of effect are poorly understood. We evaluated multi‐scale effects of land cover, weather, and fire histories on patterns of abundance and productivity for Columbian sharp‐tailed grouse populations during 1995–2020 in Idaho, USA, using mixed‐effects generalized regression and remotely sensed data. We demonstrated negative effects of fire, tree encroachment, and bare ground, positive effects of spring and summer precipitation and cover of shrubs and perennial forbs and grasses, and positive effects of CRP on grouse abundance that changed in magnitude with cover of perennials and shrubs near leks (i.e., strongest effects when average cover of shrubs and perennial forbs and grasses were less abundant). We also demonstrated per capita recruitment of Columbian sharp‐tailed grouse is positively associated with late‐summer greenness. Our results show that several suspected threats have measurable, population‐level impacts to Columbian sharp‐tailed grouse within Idaho. Moreover, our results suggest ongoing changes occurring within the core range of Columbian sharp‐tailed grouse, including loss of CRP cover to tilled agriculture and changes to wildfire and precipitation dynamics are likely to have negative effects on populations. [ABSTRACT FROM AUTHOR]

Land cover change is the largest direct driver of global biodiversity loss but often the relationships between habitats and species occurrence are unknown. The conservation community requires tools to assess variation in biodiversity related to land cover for maximizing return on investment. Our objectives were to 1) develop a biodiversity mapping and assessment tool at a fine spatial scale for terrestrial vertebrates, and 2) test how much biodiversity is conserved by retaining natural habitats within agricultural landscapes. We built species distribution models for amphibians, birds, mammals, and reptiles (329 species, > 1.2 million observations) within Prairie Canada. Predicted biodiversity within 805 m × 805 m sites ranged from 0 to 238 species (66 ± 0.1). The proportion of annual cropland at a site had the largest negative effect on biodiversity among predictors. Using simulations of land cover change, we predicted that conserving 20 % of natural habitats would conserve an average of 26.5 % of maximum species richness in fields with annual cropland and 74.3 % of maximum species richness in fields with tame grass (perennial cropland). Our tool predicted that fields with conservation easements (n = 312) had more species (114 ± 2) and natural habitat (48 ± 1 %) compared to nearby unprotected sites (82 ± 3 species; 32 ± 2 % natural habitat). Our results highlight the importance of retaining natural habitats, including wetlands, grasslands, and forests within farms to support biodiversity. In addition, our predictions can be used to target areas for conserving and restoring habitats. [ABSTRACT FROM AUTHOR]

Anthropic actions have motivated pieces of research on the impacted naturally poor soils of the Brazilian Amazon, requiring the use of diagnostic attributes that are increasingly specific to each environmental change. The use of magnetic proxies inherent in the soil may be the key to understanding the changes that occur in the soil and the environment. Therefore, this study aimed to characterize the physical, chemical and mineralogical properties of Alisols, in addition to determining the intensity and origin of the magnetic signal for future calibrations as an environmental proxy for monitoring soil fertility. One natural and three cultivated Alisols were sampled using systematic meshes in three layers: 0–5, 5–10 and 10–20 cm. The natural Alisol is a tropical forest and the agricultural ones refer to the cultivation of annatto, cupuaçu and guarana. A total of 192 samples/area were submitted to physical, chemical, mineralogical and magnetic susceptibility (MS) analysis. MS measured at low and high frequency and converted to specific mass (χ lf and χ hf), then descriptive, univariate and multivariate statistical analyzes were applied to the results. The conversion of the physically good and chemically poor and acidic natural Alisols to agricultural crops, caused an increase in the density and amplitude of the pH in water and Al3+ of the soil, plus a reduction in macroporosity, gravimetric humidity, available phosphorus and iron oxalate contents, and the incorporation of organic carbon in depth. All Alisols showed low χ lf and χ hf. However, χ lf values decreased in depth for cultivated Alisols (0.53–0.26 x 10−6 m3 kg−1), whereas, for natural Alisol, these values tended to increase towards the subsurface (0.21–0.23 x 10−6 m3 kg−1). Nevertheless, the value of χ lf and χ hf were highly representative within the cultivation areas, which was characterized as a suitable proxy to monitor the fertility of the Alisols in the Amazon region. • Converting natural Alisols to crops changes their physical and chemical attributes. • Alisols from Amazonas have low χ lf and χ hf. • Cultivated Alisols have χ lf and χ hf with behavior opposite to the natural one. • χ lf and χ hf are potential proxies to monitor small variations in Alisols attributes. [ABSTRACT FROM AUTHOR]

Changes in primary cover for agricultural crops in Amazonas region influence the phenomenon of spatial variability in soil properties. This phenomenon is still studied assuming that the spatial data is isotropic, but does not consider the anisotropic pattern of soil properties. Thus, the aim of this work was to characterize, identify and correct isotropic patterns of magnetic susceptibility (MS) measurements using anisotropic models that actually represent the spatial aspects of the data. Three cultivation areas and one under native forest, classified as Haplic Alisol, were georeferenced and sampled by a mesh system covering 192 samples per area. Texture, X-ray diffraction and frequency-dependent (χfd) and mass-specific (χlf and χhf) magnetic susceptibility analyzes were performed. Then, classical and geostatistical analyzes were applied to the data, assuming isotropy and anisotropy. All χ frequencies were shown to be spatially dependent, satisfying the isotropy hypothesis. Thereby, the application of anisotropic analysis was able to confirm the presence of all types of anisotropy in Alisols. Anisotropic correction provided an improvement in models that fit the directional trends within the areas, and provided a reduction in the nugget effect and an increase in the correlation ranges. Thus, the generated kriging maps improved the patches of zonal trends of greater or lesser χ that stand out at the level of sub-regions. These zones should, therefore, be used as indicators of variability, paying special attention during their management, especially in research related to the delimitation of specific management zones. [ABSTRACT FROM AUTHOR]

Agricultural expansion drives biodiversity loss globally, but impact assessments are biased towards recent time periods. This can lead to a gross underestimation of species declines in response to habitat loss, especially when species declines are gradual and occur over long time periods. Using Cold War spy satellite images (Corona), we show that a grassland keystone species, the bobak marmot (Marmota bobak), continues to respond to agricultural expansion that happened more than 50 years ago. Although burrow densities of the bobak marmot today are highest in croplands, densities declined most strongly in areas that were persistently used as croplands since the 1960s. This response to historical agricultural conversion spans roughly eight marmot generations and suggests the longest recorded response of a mammal species to agricultural expansion. We also found evidence for remarkable philopatry: nearly half of all burrows retained their exact location since the 1960s, and this was most pronounced in grasslands. Our results stress the need for farsighted decisions, because contemporary land management will affect biodiversity decades into the future. Finally, our work pioneers the use of Corona historical Cold War spy satellite imagery for ecology. This vastly underused global remote sensing resource provides a unique opportunity to expand the time horizon of broad-scale ecological studies. [ABSTRACT FROM AUTHOR]

In densely populated fire-prone regions, interactions between global change drivers, such as land-cover changes and climate change, may increase the frequency and severity of wildfires impacting forest ecosystems, thus diminishing their capability of provisioning key ecosystem goods and services for these societies. Yet, landscape mosaics play a crucial role in fire dynamics and behaviour. Here, we argue that promoting heterogeneous agro-forest mosaics could reduce the area affected by future fires. Specifically, we evaluated 24 landscape-scale management scenarios based on agricultural conversion, i.e. the creation of new agricultural land, that also explicitly incorporated fire suppression. Scenarios differed in the annual rate of such conversion, the spatial pattern (aggregate vs. scattered), and the location of new agricultural patches. To quantify the interactions between vegetation dynamics, fires, land-cover changes, and fire suppression, we coupled two spatially explicit models: a landscape dynamic fire-succession model and a land-cover change model. When applied to the Mediterranean region of Catalonia (NE Spain), new landscape mosaics favoured firefighting extinction capacity only after 15 years (on average) of cumulative land transformations. Agricultural conversion of at least 100 km2 year−1 was required to reduce total area burnt. A conversion rate of 200 km2 year−1 substantially improved fire suppression effectiveness, but subsequent conversion increases did not. When aggregated, new agriculture patches contributed more effectively to reduction in total area burnt and decreased the edge effect on remaining forest patches. Agricultural conversion in Mediterranean landscapes opens a new window for long-term spatial planning aimed at minimizing negative impacts of wildfire on forest ecosystems. These alternative strategies could help to develop landscape management practices in other fire-prone regions. [ABSTRACT FROM AUTHOR]

Rapid expansion of cropland threatens grassland ecosystems across western North America and broad-scale planning can be a catalyst motivating individuals and agencies to accelerate conservation. Sprague's Pipit ( Anthus spragueii ) is an imperiled grassland songbird whose population has been declining rapidly in recent decades. Here, we present a strategic framework for conservation of pipits and their habitat in the northern Great Plains. We modeled pipit distribution across its million-km 2 breeding range in Canada and the U.S. We describe factors shaping distribution, delineate population cores and assess vulnerability to future grassland losses. Pipits selected landscapes with a high proportion of continuous grassland within a relatively cool, moist climate. Sixty percent of the global breeding population occurred in Canada and 63% of the U.S. population occurred in Montana. Populations were highly clumped, with 75% of birds within 30% of their range. Approximately 20% of the population occurred on protected lands and over half used lands that were unlikely to be cultivated given current technologies. A quarter of pipits relied on remaining arable grasslands and potential population losses varied from 2–27% across scenarios. Most of the population (70%) was dependent on private lands, emphasizing the importance of voluntary approaches that incentivize good stewardship. Our maps depicting core populations and tillage risk enable partners to target conservation in landscapes where pipits will benefit most. [ABSTRACT FROM AUTHOR]

Abstract: The expansion of agricultural plantations at the expense of forest drives dramatic losses of biodiversity and carbon. Consumers are now demanding sustainability in tropical agriculture and producers are responding with questionable certification standards. Many certification schemes—including those for oil palm, soy, sugar cane and cacao—rely upon the High Conservation Value (HCV) concept to prevent unacceptable losses of biodiversity to agricultural conversion. This concept protects very rare species or habitats, exceptional concentrations of wildlife, or large landscape-level areas of forest. Yet much biodiversity persists below these thresholds yielding the spectre of unsustainable conversion of forest to certified plantation crops under a green label. To meet more rigorous standards of sustainability, tropical plantations would have to retain large patches of native forests in the matrix. We highlight six critical areas in need of consideration by conservation scientists, practitioners and certification processes. In particular, the application of HCV to sustainable agricultural development at the national-level, the use of Imperata grasslands and abandoned agriculture, the creation of Biobanks, and increased price premiums for certified crops could redound to the long-term protection of tropical biodiversity. [Copyright &y& Elsevier]

The article presents a case study on the impact of the reduced-impact logging (RIL), conventional logging (CL), and primary (unlogged) forests on birds, dung beetles, and leaf-litter ants in Sabah, Borneo. Unlogged forests significantly differed to RIL and CL based to the composition of bird and ant species. Result shows that the biodiversity from RIL and CL have a difference in a short time, but its benefits may fall over the longer time after the cessation of logging.

Both invasive alien trees and agricultural conversion have major impacts on biodiversity. We studied here the comparative impact of these two types of land transformation on a wide range of surface-active arthropod species using pitfall traps, with evergreen sclerophyllous natural vegetation (fynbos) as the control. The study was in the Cape Floristic Region, a global biodiversity hotspot, where alien trees are of major concern and where vineyards replace natural fynbos vegetation. Surface-active arthropods were selected as they are species rich, relatively immobile, and occur in high abundance. We hypothesized that the impact of the two types of land cover transformation would produce similar qualitative and quantitative effects on the arthropods. We also compared the results in the transformed and natural areas with those in areas cleared of alien trees. Arthropod species richness in cleared areas was higher than in vineyards and more similar to that in natural fynbos, while alien trees had the lowest. Overall abundance scores were highest in cleared areas, closely followed by fynbos, then vineyards and lowest in alien trees. Several species were restricted to each vegetation type, including alien trees. In terms of assemblage composition, all vegetation types were significantly different, although fynbos and vineyards grouped, suggesting that vineyards have less impact on the arthropod community than do alien trees. When rare species were excluded, vineyards and cleared sites grouped, indicating some recovery but only involving those species that were common and habitat tolerant. Our results suggest that vineyards retain a greater complement of indigenous species than alien trees, but that clearing of these aliens soon encourages establishment of indigenous species. Although there were significant differences in soil moisture and litter depth within and between vegetation types, we did not record them as significantly affecting species richness or abundance, even in alien vegetation, an encouraging sign for restoration. [ABSTRACT FROM AUTHOR]

Abstract: Iron cycling in wetlands is important because it plays an important role in interactions among wetland soils/sediments, plants and microorganisms. The seasonal variation of iron (Fe) distributed in two freshwater peatland ecosystems dominated by Calamagrostis angustifolia (CA) and Carex lasiocarpa (CL), was observed in Sanjiang Plain of Northeast China. The compartmentalization of the Fe cycle including storage in the atmosphere, litter, soil, and above- and below ground plant material was determined. The results showed that the Fe input from rain was 0.06gm−2 a−1, and the total Fe mass in the peatland ecosystem was 5.18×103 for CA and 1.40×103 gm−2 for CL. The major Fe pools were soils (98.6% and 97.1% for CA and CL, respectively). The Fe fluxes between each compartment resulted in the increase of the belowground Fe pool and decrease of the litter Fe pool currently both for CA and CL. CL has greater uptake coefficient (0.024) and cycle coefficient (0.034), but smaller use coefficient (0.58) than that of CA (0.02, 0.006, and 0.77, respectively). Peatland conversion for agriculture affected the former natural Fe cycle processes and mass balance to a certain extent in long term, because the Fe assimilated by soybean and rice are less than that of CA and CL, and cannot return to soils from harvesting. Drainage and ditch excavation for agricultural conversion caused considerable Fe loss via aqueous movement, so that Fe was likely lost and transported downstream by these ditch networks. [Copyright &y& Elsevier]

gricultural drainage is thought to alter greenhouse gas emissions from temperate peatlands, with CH emissions reduced in favor of greater CO losses. Attention has largely focussed on C trace gases, and less is known about the impacts of agricultural conversion on NO or global warming potential. We report greenhouse gas fluxes (CH, CO, NO) from a drained peatland in the Sacramento-San Joaquin River Delta, California, USA currently managed as a rangeland (that is, pasture). This ecosystem was a net source of CH (25.8 ± 1.4 mg CH-C m d) and NO (6.4 ± 0.4 mg NO-N m d). Methane fluxes were comparable to those of other managed temperate peatlands, whereas NO fluxes were very high; equivalent to fluxes from heavily fertilized agroecosystems and tropical forests. Ecosystem scale CH fluxes were driven by 'hotspots' (drainage ditches) that accounted for less than 5% of the land area but more than 84% of emissions. Methane fluxes were unresponsive to seasonal fluctuations in climate and showed minimal temporal variability. Nitrous oxide fluxes were more homogeneously distributed throughout the landscape and responded to fluctuations in environmental variables, especially soil moisture. Elevated CH and NO fluxes contributed to a high overall ecosystem global warming potential (531 g CO-C equivalents m y), with non-CO trace gas fluxes offsetting the atmospheric 'cooling' effects of photoassimilation. These data suggest that managed Delta peatlands are potentially large regional sources of greenhouse gases, with spatial heterogeneity in soil moisture modulating the relative importance of each gas for ecosystem global warming potential. [ABSTRACT FROM AUTHOR]

The likely Reducing Emissions from Deforestation and Degradation (REDD+) mechanism includes strategies for the enhancement of forest carbon stocks. Recent concerns have been expressed that such enhancement, or restoration, of forest carbon could be counterproductive to biodiversity conservation, because forests are managed as 'carbon farms' with the application of intensive silvicultural management that could homogenize diverse degraded rainforests. Restoration increases regeneration rates in degraded forest compared to naturally regenerating forest, and thus could yield significant financial returns for carbon sequestered. Here, we argue that such forest restoration projects are, in fact, likely to provide a number of benefits to biodiversity conservation including the retention of biodiversity, the prevention of forest conversion to agriculture, and employment opportunities for poor local communities. As with other forms of forest-based carbon offsets, there are possible moral hazard and leakage problems with restoration. However, due to the multiple benefits, we urge that enhancement of forest carbon stocks be detailed as a major component in the future negotiations of REDD+. [ABSTRACT FROM AUTHOR]

Abstract: Designing conservation areas entails costs that, if considered explicitly, can be minimized while still achieving conservation targets. Here we focus on opportunity costs which measure forgone benefits from alternative land uses. Conservation planning studies often use partial estimates of costs, but the extent to which these result in actual efficiencies has not been demonstrated. Our study partitions land costs into three distinct opportunity costs to smallholder agriculture, soybean agriculture and ranching. We demonstrate that opportunity costs to single stakeholder groups can be inaccurate measures of true opportunity costs and can inadvertently shift conservation costs to affect groups of stakeholders disproportionately. Additionally, we examine how spatial correlations between costs as well as target size affect the performance of opportunity costs to single stakeholder groups as surrogate measures of true opportunity costs. We conclude that planning with opportunity costs to single stakeholder groups can result in cost burdens to other groups that could undermine the long-term success of conservation. Thus, an understanding of the spatial distributions of opportunity costs that are disaggregated to groups of stakeholders is necessary to make informed decisions about priority conservation areas. [Copyright &y& Elsevier]

Conservation scientists recognize the urgency of incorporating opportunity costs into conservation planning. Despite this, applications to date have been limited, perhaps partly because of the difficulty in determining costs in regions with limited data on land prices and ownership. We present methods for estimating opportunity costs of land preservation in landscapes or ecoregions that are a changing mix of agriculture and natural habitat. Our approach derives from the literature on estimating land values as opportunity costs of alternate land uses and takes advantage of general availability of necessary data, even in relatively data-poor regions. The methods integrate probabilities of habitat conversion with region-wide estimates of economic benefits from agricultural land uses and estimate land values with a discount rate to convert annual values into net present values. We applied our method in a landscape undergoing agricultural conversion in Paraguay. Our model of opportunity costs predicted an independent data set of land values and was consistent with implicit discount rates of 15–25%. Model-generated land values were strongly correlated with actual land values even after correcting for the effect of property size and proportion of property that was forested. We used the model to produce a map of opportunity costs and to estimate the costs of conserving forest within two proposed corridors in the landscape. This method can be applied to conservation planning in situations where natural habitat is currently being converted to market-oriented land uses. Incorporating not only biological attributes but also socioeconomic data can help in the design of efficient networks of protected areas that represent biodiversity at minimum costs. [ABSTRACT FROM AUTHOR]