Between‐Patch Bird Movements within a High‐Andean Polylepis Woodland/Matrix Landscape: Implications for Habitat Restoration

The movement ability of species in fragmented landscapes must be considered if habitat restoration strategies are to allow maximum benefit in terms of increased or healthier wildlife populations. We studied movements of a range of bird species between woodland patches within a high‐altitude Polylepis/matrix landscape in the Cordillera Vilcanota, Peru. Movement rates between Polylepis patches differed across guilds, with arboreal omnivores, arboreal sally‐strikers and nectarivores displaying the highest movement rates, and understorey guilds and arboreal sally‐gleaners the lowest movement rates. Birds tend to avoid flights to more distant neighboring patches, especially when moving from patches which were themselves isolated. The decline in bird flight frequencies with increasing patch isolation followed broken‐stick models most closely, and while we suggest that there is evidence for a decline in between‐patch movements over distances of 30–210 m, there was great variability in movement rates across individual patches. This variability is presumably a result of complex interactions between patch size, quality and configuration, and flight movement patterns of individual bird species. Our study does, however, highlight the contribution small woodland patches make toward fragmented Polylepis ecosystem functioning, and we suggest that, where financial resources permit, small patch restoration would be an important compliment to the restoration of larger woodland patches. Most important is that replanting takes place within 200 m or so of existing larger patches. This will be especially beneficial in allowing more frequent use of woodland elements within the landscape and in improving the total area of woodland patches that are functionally connected.     

Fruit‐feeding Butterfly Communities are Influenced by Restoration Age in Tropical Forests

Currently, a large‐scale restoration project aims to restore around 15 million hectares of Atlantic Forest in Brazil. This will increase forest cover and connectivity among remnant sites as well as restore environmental services. Currently, studies on recovery of fauna in restored areas of the Atlantic Forest are practically nonexistent. To address this knowledge vacuum, our study compares diversity patterns of fruit‐feeding butterflies in three forest areas with different restoration ages (11, 22, and 54 years), and uses a native forest area as reference. Results showed butterfly communities in maturing restored areas becoming more similar to the ones found in the native forest, with an increase in the proportional abundance of forest species, and a decrease of edge and grassland species. Moreover, we found a higher diversity among sites at the intermediate restoration age, with a community composed of both grassland and forest species. Butterfly species composition differed significantly among sites, showing interesting patterns of potential species replacement over time. Our results indicate that, although restored sites were located in a fragmented landscape, they provide suitable habitats for recolonization by fruit‐feeding butterfly assemblages. Hence, restored areas can be considered important habitat for forest animal species, increasing local biodiversity and, possibly, restoring some of the ecosystem services provided by them.     

Landscape Transformations and loss of Atlantic Forests: challenges for conservation

Regions of intense fragmentation and landscape transformation can indicate patterns of conversion of forest areas in space and time, challenging the resilience of ecosystems and driving the degradation of natural resources. In this study, we analyzed the dynamics of use, loss, and gain of Atlantic forests in the southern region of Bahia State in the last thirty-four years (1985–2019) based on pre and post-implementation of forest production policies. The area has ecological, historical, and cultural importance, and is the most conserved portion of the Atlantic Forest in northeastern Brazil. From the remote sensing products of the MapBiomas Project and spatial analyses of land use and forests, we evaluated a conflicted region that has 751 km of coastline and seventy municipalities. Our results indicate a degraded landscape, with 59% of the territory occupied by anthropogenic activities and intense fragmentation. The planting of eucalyptus forests and pasture stood out as landscape modifiers. The results show a loss of 328,595 ha of Atlantic Forest in the period under study, with a large part of this area being replaced by planted forests of Eucalyptus sp derivated the policies economics of the sector. It is urgent to consider the recovery of the Atlantic domain, prioritizing the capacity of ecosystems, especially in the Decade of Restoration.     

Regional‐Scale Variation in Litter Production and Seasonality in Tropical Dry Forests of Southern Mexico1

Highly seasonal rainfall creates a pulse of litterfall in the southern Yucatan peninsula region, with cascading effects on the timing of essential nutrient fluxes, microbial dynamics, and vegetation growth. I investigated whether forest age or a regional environmental gradient related to rainfall has a greater effect on patterns of litterfall in this increasingly human‐dominated landscape. Litterfall was sampled in 10–13 stands in each of three locations spanning a rainfall gradient of ca 900–1400 mm/yr. Litter was collected monthly from November 1998 through January 2000 in mature forests and in secondary forests aged 2–25 yr. Despite a substantial precipitation gradient, age was the only significant predictor of annual litter mass. Two‐ to five‐yr‐old forests produced significantly less litter than 12–25‐yr‐old secondary forests (4.6 vs. 6.2 Mg/ha/yr), but the difference between older secondary forests and mature forests (9 percent) was not significant. Litter production increased with rainfall, but not significantly so. The pattern of litterfall was similar across locations and age classes, with a peak during late March or early April. However, litterfall seasonality was most pronounced in the old secondary and mature forests. Litterfall was more evenly distributed throughout the year in forests under 10 yr old. Seasonality of litterfall was also less pronounced at the wettest site, with less disparity between peak litterfall and off‐peak months. Seasonality was not related to soil texture. Forest age and rainfall are important drivers of litterfall dynamics; however, both litter mass and degree of seasonality depended more strongly on forest age. Thus, the impact of land‐use change on litter nutrient cycling is as great, if not greater, than the constraint imposed by the major natural environmental factor affecting tropical dry forests.     

The Restoration of Degraded Mountain Woodlands: Effects of Seed Provenance and Microsite Characteristics on Polylepis australis Seedling Survival and Growth in Central Argentina

South American high‐mountain ecosystems are greatly influenced by human disturbance. In the mountains of Córdoba, Argentina, Polylepis australis (Rosaceae) woodlands are currently highly fragmented and subject to extensive burning and livestock grazing, resulting in severe changes of habitat characteristics, which hamper natural regeneration. In order to find out how to achieve successful reforestation, we compared P. australis seedling survival and growth and the development of a shrubby habit for two seed provenances and different planting microsites. Survival of planted seedlings after 5 years was 70%, with most deaths (19%) in the first year and declining mortality with ongoing establishment. Survival did not show any relationship with seed provenance or microsite characteristics. Height growth averaged 34.6 ± 1.2 cm in 5 years. Seedlings produced from seeds collected in a well‐preserved woodland grew taller and showed a higher tendency for development of shrubby habit than those produced from seeds collected in a degraded woodland. Seedlings planted in more degraded microsites with exposed soil or rock due to past grazing pressure grew less and developed a more shrubby habit than those planted in better preserved microsites. Our results show that restoration of degraded areas with P. australis is possible and that there is potential to improve restoration success with a careful selection of seed provenance and planting microsites.     

An analysis of long‐term trends in the abundance of domestic livestock and free‐roaming dogs in the Bale Mountains National Park,Ethiopia

Livestock inside the Bale Mountains National Park poses a threat to the persistence of the Ethiopian wolf (Canis simensis) through grazing‐induced habitat degradation and the transmission of diseases from the domestic dogs kept alongside the herds. We used a 21‐ year time series to explore long‐term trends in the numbers of cattle, caprines and free‐roaming domestic dogs in two core Ethiopian wolf areas (the Web valley and the Sanetti plateau) and to test whether seasonal variations in primary productivity underlies the current livestock production system. No trends in livestock numbers were detected in the Web valley, where livestock are most abundant and graze seasonally. Livestock numbers have increased significantly on most of the Sanetti plateau, grazing all year‐round albeit at a lower intensity. Livestock use of the Web valley was positively correlated with vegetation productivity as derived from remotely sensed data, the Normalized Difference Vegetation Index (NDVI). On the Sanetti plateau, neither primary productivity nor livestock numbers showed signs of strong seasonality. The current livestock production system has the potential to degrade the vegetation that sustains the wolves’ rodent prey while an increase in free‐roaming domestic dogs in parts of their range may heighten the risk of disease transmission.     

Reclaiming Degraded Rainforest: A Spatial Evaluation of Gains and Losses in Subtropical Eastern Australia to Inform Future Investment in Restoration

Forest restoration is expected to play a pivotal role in reducing extinctions driven by deforestation and climate change over the next century. However, spatial and temporal patterns of restoration (both passive and active) are likely to be highly variable depending on degree of land use change as well as levels of forest and soil degradation and residual vegetation. Uncertainties regarding the spatial and temporal reinstatement of forest on degraded land make it difficult to determine where future investment in active restoration should be targeted. We used satellite data to quantify change in the extent and foliage projection cover (FPC) of woody vegetation returning to land previously cleared of subtropical rainforest in eastern Australia. We show a modest recovery of woody vegetation but document high variability in this trend between local areas, expanding by over 5% in some situations but declining by up to 2% in others over the last decade (1999–2009 period). This was accompanied by minor change in average FPC (?0.2 to 4.2%). Overall, decadal expansion in woody vegetation was most apparent in local areas with intermediate levels of existing forest reestablishment and was most likely to occur on steep terrain near existing vegetation. These results provide a valuable first evaluation of where restoration is occurring and the likely time frame required to meet conservation objectives under a business as usual scenario. This knowledge enables returns from current investment to be quantified and can be used to better allocate funds for restoration in the future.     

Landscape correlates of forest plant invasions: A high‐resolution analysis across the eastern United States

Aim

Invasive species occurrence is often related to the anthropogenic context of a given area. Quantifying the effects of roads is of particular interest as roads are a major vector for invasion. Our objective was to further quantify the effects of roads on forest plant invasion through a macroscale, high‐resolution investigation to assist effective invasion control and mitigation.

Location

Eastern United States.

Methods

Using invasive plant data from 23,039 forest inventory plots in 13 ecological provinces, we employed logistic regression to relate the odds of invasion to distance from a road, with adjustments for broadscale differences attributable to ecological provinces, and local scale differences in productivity, forest fragmentation and land use.

Results

The overall proportion (P) of invaded plots was 0.58 (0.65 for plots within 50 m of a road), and the highest odds (P/1 ? P) of invasion were found in relatively more productive, fragmented forest in landscapes with more than 10% agriculture or developed land cover. Wald chi‐square statistics indicated the best predictor of the odds of invasion was ecological province, followed by land use, productivity, forest fragmentation and distance from a road. Depending on the province, the adjusted odds of invasion decreased by up to 23% (typically 4%–10%) per 100 m distance from a road. The adjusted probability of invasion approached zero in only three provinces, for the least productive, least fragmented forest that was at least 2,000 m from a road in landscapes with less than 10% agricultural or developed land cover.

Main conclusions

In the eastern United States, the existence of a nearby road is less important than the landscape context associated with the road. A purely road‐mediated effect has little practical meaning because anthropogenic activities and roads are pervasive and confounded.

     

Searching for Leverage to Conserve Forests: The Industrial Ecology of Wood Products in the United States

The forest and the creatures it shelters exemplify nature, and logging exemplifies the impacts of humans. In the 1990s Americans annually removed 70% more timber from the forest than in 1900. Since I900 population rose more than three times and gross domestic product (GDP) per person almost five. Despite more people, affluence, and logging, U.S. forest area remained constant. Since mid-century, standing timber volume me nearly 30%. Consumers, millers, and foresters, responding to changes in style, ethics, and technology, have contributed to these outcomes. We examine the role of each actor in the industrial ecology of forests for their leverage for sparing forests. Consumers lessened their use of wood products per GDP (Intensity of Use) during the century by 2.5% annually to offset expanding population and GDP per person, a trend that will level or lower timber consumption if population and affluence grow as expected. Millers became highly efficient at utilizing wood and recycled fiber for their material or energy, a success that limits their fcrture leverage. Foresters have leverage to grow trees faster and thus use less forest land to grow and harvest timber. Steady or declining demand for trees coupled to productive forests could spare more US. forest land for sequestering carbon, ecosystem services, and habit for nature.     

Long-Term Effects of Forest Regrowth and Selective Logging on the Seed Bank of Tropical Forests in NE Costa Rica1.

To investigate long-term effects of land use on the soil seed bank, we compared the abundance/density, species richness, life form distribution, and species composition of seeds stored in the soil of four 15–20 yr-old second-growth stands, two old-growth stands, and two previously selectively-logged stands in the Caribbean lowlands of Costa Rica. Surface soil (10 cm deep, 4.7 cm diameter) was collected at 10 m intervals along three 120–160 m long transects in each stand (44–48 soil cores, 22–24 combined seed bank samples per site). Seed density was highest but variable in second-growth stands (8331–14535 seeds/m²), low and homogeneous in old-growth stands (2258–2659 seeds/m²), and intermediate and highly variable in selectively-logged stands (1165–6854 seeds/m²), which also had contrasting logging intensities. Species richness was strongly dependent on seed density, but showed less variation. Life form distribution did not differ statistically among or within land-use categories. In each stand, herbs-forbs, shrubs, and vines dominated the seed bank (> 75% of the species richness and abundance), whereas trees were a minor component (< 20% of the species richness and < 5% of the abundance) and were predominandy early successional. Shrubs and vines were most abundant in second-growth stands where regrowth vegetation was repeatedly cut before abandonment, whereas grasses and sedges were most abundant in the only forest stand that was completely surrounded by pastures. In terms of species composition, old-growth stands were more similar to selectively-logged stands than to second-growth stands, but across stands, selectively-logged forests were most distinct from the other two forest types. An inventory of the standing woody vegetation in each site showed little representation of the woody taxa found in the seed bank. We discuss these results in the context of the main factors that have been postulated to influence the abundance, life form, and species composition of tropical forest seed banks, and explore the role of the latter during intermediate phases of tropical forest succession and regeneration.     

Hotspots of uncertainty in land‐use and land‐cover change projections: a global‐scale model comparison

Model‐based global projections of future land‐use and land‐cover (LULC) change are frequently used in environmental assessments to study the impact of LULC change on environmental services and to provide decision support for policy. These projections are characterized by a high uncertainty in terms of quantity and allocation of projected changes, which can severely impact the results of environmental assessments. In this study, we identify hotspots of uncertainty, based on 43 simulations from 11 global‐scale LULC change models representing a wide range of assumptions of future biophysical and socioeconomic conditions. We attribute components of uncertainty to input data, model structure, scenario storyline and a residual term, based on a regression analysis and analysis of variance. From this diverse set of models and scenarios, we find that the uncertainty varies, depending on the region and the LULC type under consideration. Hotspots of uncertainty appear mainly at the edges of globally important biomes (e.g., boreal and tropical forests). Our results indicate that an important source of uncertainty in forest and pasture areas originates from different input data applied in the models. Cropland, in contrast, is more consistent among the starting conditions, while variation in the projections gradually increases over time due to diverse scenario assumptions and different modeling approaches. Comparisons at the grid cell level indicate that disagreement is mainly related to LULC type definitions and the individual model allocation schemes. We conclude that improving the quality and consistency of observational data utilized in the modeling process and improving the allocation mechanisms of LULC change models remain important challenges. Current LULC representation in environmental assessments might miss the uncertainty arising from the diversity of LULC change modeling approaches, and many studies ignore the uncertainty in LULC projections in assessments of LULC change impacts on climate, water resources or biodiversity.     

Restoration ecology in the Anthropocene: learning from responses of tropical forests to extreme disturbance events

Extreme disturbance events denote another aspect of global environmental changes archetypal of the Anthropocene. These events of climatic or anthropic origin are challenging our perceived understanding about how forests respond to disturbance. I present a general framework of tropical forest responses to extreme disturbance events with specific examples from tropical dry forests. The linkage between level of disturbance severity and dominant mechanism of vegetation recovery is reflected on a variety of initial trajectories of forest succession. Accordingly, more realistic and cost‐effective restoration goals in many tropical forests likely consist in maintaining a mosaic of different successional trajectories while promoting landscape connectivity, rather than encouraging full‐ecosystem recovery to pre‐disturbance conditions. Incorporating extreme disturbance events into the global restoration ecology agenda will be essential to design well‐informed ecosystem management strategies in the coming decades.     

Thinking Locally for Urban Forest Restoration: A Simple Method Links Exotic Species Invasion to Local Landscape Structure

Restoring urban forests often involves eradicating exotic species and diligently guarding against future invasions. Understanding how landscape structure contributes to the distribution of exotic species may inform these management efforts. To date, the distribution of exotic species in forested patches has been correlated with the type of development surrounding the patch, with those surrounded by agricultural or urban development often more highly invaded. Yet, previous studies have categorized land use types and have not examined more local-scale changes in land use. These local changes may be particularly important in urban areas where forested patches are immediately surrounded by diverse land use types. Our study examined how two key aspects of landscape structure, patch size and adjacent land use, may influence patterns of exotic species invasion of riparian buffers within Raleigh and Cary, North Carolina, United States. We found that large patch size alone, in our case, wide riparian buffers, does not protect against exotic species invasion. Patches surrounded by higher canopy-cover landscapes (e.g., forests and older residential developments with mature canopy) were more likely to be invaded than those surrounded by less canopy cover (e.g., shopping malls and other commercial development). We attribute these results, in part, to increased pressure from exotic propagules from adjacent forests. When restoring urban forests, attention should be paid to local land use to better plan for successful, long-term eradication of exotic species.     

High‐Rate Charging Induced Intermediate Phases and Structural Changes of Layer‐Structured Cathode for Lithium‐Ion Batteries

Using fast time‐resolved in situ X‐ray diffraction, charge‐rate dependent phase transition processes of layer structured cathode material LiNi_1/3Mn_1/3Co_1/3O₂ for lithium‐ion batteries are studied. During first charge, intermediate phases emerge at high rates of 10C, 30C, and 60C, but not at low rates of 0.1C and 1C. These intermediate phases can be continuously observed during relaxation after the charging current is switched off. After half‐way charging at high rate, sample studied by scanning transmission electron microscopy shows Li‐rich and Li‐poor phases' coexistence with tetrahedral occupation of Li in Li‐poor phase. The high rate induced overpotential is thought to be the driving force for the formation of this intermediate Li‐poor phase. The in situ quick X‐ray absorption results show that the oxidation of Ni accelerates with increasing charging rate and the Ni⁴⁺ state can be reached at the end of charge with 30C rate. These results give new insights in the understanding of the layered cathodes during high‐rate charging.     

Release of Juniperus thurifera woodlands from herbivore‐mediated arrested succession in Spain

Question: Do abiotic constraints maintain monospecific woodlands of Juniperus thurifera? What is the role of biotic (livestock) versus abiotic (climate) drivers in the recruitment and growth of the different tree species? Location: Cabrejas range, Soria, north‐central Spain, 1200 m altitude. Methods: Stand history was reconstructed using dendro‐ecology and spatial pattern analysis, combined with historical data of livestock abundances and climatic records. Results: J. thurifera establishment occurred in two distinct pulses, with a tree component establishing in the late 1800s to early 1900s. Quercus ilex and Pinus sylvestris establishment was evident only from the late 1970s onward. Recruitment events were related to reductions in livestock browsing. J. thurifera spatial structure was clumped and Q. ilex showed a short‐scale aggregation to J. thurifera trees and saplings. Radial growth trends of J. thurifera saplings, Q. ilex and P. sylvestris were negatively related to livestock density. Summer drought limited the radial growth of all the study species, and P. sylvestris and Q. ilex grew faster than J. thurifera even after considering an age effect. Conclusions: The differences in radial growth patterns and recruitment pulses between species indicate that livestock browsing and not abiotic factors is the main factor controlling plant succession and structural development. In this process, J. thurifera acts as a nurse plant, facilitating the establishment of other tree species. Under the current low pressure from herbivores, formerly pure J. thurifera woodlands will change towards dense stands of mixed species composition.     

Avian ecological succession in the Amazon: A long‐term case study following experimental deforestation

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Multiple successional pathways in human‐modified tropical landscapes: new insights from forest succession,forest fragmentation and landscape ecology research

Old‐growth tropical forests are being extensively deforested and fragmented worldwide. Yet forest recovery through succession has led to an expansion of secondary forests in human‐modified tropical landscapes (HMTLs). Secondary forests thus emerge as a potential repository for tropical biodiversity, and also as a source of essential ecosystem functions and services in HMTLs. Such critical roles are controversial, however, as they depend on successional, landscape and socio‐economic dynamics, which can vary widely within and across landscapes and regions. Understanding the main drivers of successional pathways of disturbed tropical forests is critically needed for improving management, conservation, and restoration strategies. Here, we combine emerging knowledge from tropical forest succession, forest fragmentation and landscape ecology research to identify the main driving forces shaping successional pathways at different spatial scales. We also explore causal connections between land‐use dynamics and the level of predictability of successional pathways, and examine potential implications of such connections to determine the importance of secondary forests for biodiversity conservation in HMTLs. We show that secondary succession (SS) in tropical landscapes is a multifactorial phenomenon affected by a myriad of forces operating at multiple spatio‐temporal scales. SS is relatively fast and more predictable in recently modified landscapes and where well‐preserved biodiversity‐rich native forests are still present in the landscape. Yet the increasing variation in landscape spatial configuration and matrix heterogeneity in landscapes with intermediate levels of disturbance increases the uncertainty of successional pathways. In landscapes that have suffered extensive and intensive human disturbances, however, succession can be slow or arrested, with impoverished assemblages and reduced potential to deliver ecosystem functions and services. We conclude that: (i) succession must be examined using more comprehensive explanatory models, providing information about the forces affecting not only the presence but also the persistence of species and ecological groups, particularly of those taxa expected to be extirpated from HMTLs; (ii) SS research should integrate new aspects from forest fragmentation and landscape ecology research to address accurately the potential of secondary forests to serve as biodiversity repositories; and (iii) secondary forest stands, as a dynamic component of HMTLs, must be incorporated as key elements of conservation planning; i.e. secondary forest stands must be actively managed (e.g. using assisted forest restoration) according to conservation goals at broad spatial scales.     

Latitudinal range shifts in Australian flying‐foxes: A re‐evaluation

Recent range shifts towards higher latitudes have been reported for many animals and plants in the northern hemisphere, and are commonly attributed to changes in climate. Relatively little is known about such changes in the southern hemisphere, although it has been suggested that latitudinal distributions of the fruit‐bats Pteropus alecto and Pteropus poliocephalus changed during the 20th century in response to climate change in eastern Australia. However, historical changes in these species distributions have not been examined systematically. In this study we obtained historical locality records from a wide range of sources (including banding and museum records, government wildlife databases and unpublished records), and filtered them for reliability and spatial accuracy. The latitudinal distribution of each species was compared between eight time‐periods (1843–1920, 1921–1950, five 10‐year intervals between 1950 and 2000, and 2001–2007), using analyses of both the filtered point data (P. alecto 870 records, P. poliocephalus 2506) and presence/absence data within 50 × 50 km grid cells. The results do not support the hypothesis that either species range is shifting in a manner driven by climate change. First, neither the northern or southern range limits of P. poliocephalus (Mackay, Queensland and Melbourne, Victoria respectively) changed over time. Second, P. alecto's range limit extended southward by 1168 km (approximately 10.5 degrees latitude) during the twentieth century (from approximately Rockhampton, Queensland to Sydney, New South Wales). Within this zone of southward expansion (25–29°S), the percentage of total records that were P. alecto increased from 8% prior to 1950 to 49% in the early 2000s, and local count data showed that its abundance increased from several hundred to more than 10 000 individuals at specific roost sites, as range expansion progressed. Pteropus alecto expanded southward at about 100 km/decade, compared with the 10–26 km/decade rate of isotherm change, and analyses of historical weather data show that the species consequently moved into recently‐colder regions than it had previously occupied. Neither climate change nor habitat change could provide simple explanations to explain P. alecto's observed rapid range shift. More generally, climate change should not be uncritically inferred as a primary driver of species range shifts without careful quantitative analyses.