Examining the Sustainability of Tropical Island Forests: Advances and Challenges in Measurement, Monitoring, and Reporting in the U.S. Caribbean and Pacific

Forests across the U.S. and U.S. affiliated islands of the Caribbean and Pacific constitute rich and dynamic social-ecological systems that, while heterogeneous in many ways, share certain characteristics and trends that underscore the utility of sustainability assessments that go beyond single jurisdictional efforts. This paper summarizes a recent effort to assess the sustainability of tropical island forests of and politically affiliated with the U.S. using the Montréal Process criteria and indicator framework (MP C&I), which address ecological, social, economic, and institutional dimensions of forests. Forests cover 45 percent of the total area and more than 50 percent of each island jurisdiction, except Hawaii (36 percent). Forest cover is generally stable over much of the area in terms of recent reference conditions. The history of human occupation and land alteration is a prominent determinant of current conditions throughout the islands, which exhibit relatively high rates of threatened species in comparison to mainland counterparts and particularly where endemism is high. The islands also harbor significant areas of new or novel assemblages of native and non-native forest species, predominately on abandoned agricultural lands cleared of native forests long ago, which have been shown to contribute to the restoration of these degraded lands and provide many other ecosystem services at levels as high as and in some cases higher than native forests. Although industrial-level commercial timber harvest is small to nonexistent on most islands, socioeconomic and cultural linkages to forests are extensive but difficult to quantify. Amassing a foundation of data sufficient to address the MP C&I was challenging, in part due to the heterogeneity of the islands, island geography, and limited reporting capacities. We document significant improvements in the availability of data important for sustainability assessments in the last decade or so, especially with the extension of the U.S. Department of Agriculture Forest Service Forest Inventory and Analysis program to the islands. Likewise, we find the MP C&I to be a useful tool for organizing and presenting information important for assessing forest sustainability. Nevertheless, considerable data gaps remain in the areas of biodiversity, forest functions and processes, and socioeconomic conditions of forests, which are critical elements to track across the islands, particularly in the context of climate change and ongoing anthropogenic pressures.

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Hidden destruction of older forests threatens Brazil’s Atlantic Forest and challenges restoration programs

Science Advances ◽

10.1126/sciadv.abc4547 ◽

2021 ◽

Vol 7 (4) ◽

pp. eabc4547

Author(s):

Marcos R. Rosa ◽

Pedro H. S. Brancalion ◽

Renato Crouzeilles ◽

Leandro R. Tambosi ◽

Pedro R. Piffer ◽

...

Keyword(s):

Spatial Distribution ◽

Atlantic Forest ◽

Forest Cover ◽

Forest Loss ◽

Native Forest ◽

Marginal Lands ◽

Annual Basis ◽

Native Forests ◽

Expected Benefits ◽

Mechanized Agriculture

Understanding the dynamics of native forest loss and gain is critical for biodiversity conservation and ecosystem services, especially in regions experiencing intense forest transformations. We quantified native forest cover dynamics on an annual basis from 1990 to 2017 in Brazil’s Atlantic Forest. Despite the relative stability of native forest cover during this period (~28 Mha), the ongoing loss of older native forests, mostly on flatter terrains, have been hidden by the increasing gain of younger native forest cover, mostly on marginal lands for mechanized agriculture. Changes in native forest cover and its spatial distribution increased forest isolation in 36.4% of the landscapes. The clearance of older forests associated with the recut of 27% of younger forests has resulted in a progressive rejuvenation of the native forest cover. We highlight the need to include native forest spatiotemporal dynamics into restoration programs to better estimate their expected benefits and unexpected problems.

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Assesment of soil erosion by 137Cs technique in native forests in Londrina City, Parana, Brazil

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132007000700016 ◽

2007 ◽

Vol 50 (6) ◽

pp. 1051-1060 ◽

Cited By ~ 3

Author(s):

Avacir Casanova Andrello ◽

Carlos Roberto Appoloni ◽

Virgílio Franco do Nascimento Filho

Keyword(s):

Soil Erosion ◽

Soil Loss ◽

Balance Model ◽

Native Forest ◽

Mass Balance Model ◽

Erosion Process ◽

137Cs Inventory ◽

Native Forests ◽

137Cs Distribution ◽

137Cs Technique

The aim of this work was to assess the soil erosion process in native forest by the 137Cs methodology. The mass balance model was applied to assess the rates of soil loss in three native forests around of Londrina city, Paraná, Brazil. 137Cs distribution depth was of exponential type for the three forests and 137Cs inventory was 241 Bq m-2 for Mata 1, 338 Bq m-2 for Mata 2 and 325 Bq m-2 for Mata UEL. The soil loss value calculated for three native forests was: 6,684 kg ha-1 yr-1 for Mata 1, 1,788 kg ha-1 yr-1 for Mata 2 and 4,524 kg ha-1 yr-1 for Mata UEL.

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An environmental database for the status of freshwater in Greece

Global NEST Journal ◽

10.30955/gnj.000229 ◽

2013 ◽

Vol 4 (1) ◽

pp. 1-14

Keyword(s):

National Level ◽

Reference Conditions ◽

Ecological Status ◽

Anthropogenic Pressures ◽

Environmental Pressures ◽

Physico Chemical ◽

Other Information ◽

The Status ◽

Freshwater Bodies ◽

Status Data

An environmental database has been created, recording water bodies at a national level and assembling relevant data collected by various public services and institutions in charge of water resources management and research in Greece. Data consists of physico-chemical parameters, geomorphological descriptions, inventories of fauna and flora species, environmental pressures, vulnerability evaluation and other information useful for the assessment of current and future ecological status. Data gathering has proven to be a challenging task, due to the large number and the generally small size of the surface freshwater bodies as well as the numerous competent services and institutions and the multiple and sometimes conflicting responsibilities that therefore result. The latter is also partly the cause of lack of continuity of data, gaps or sometimes questionable reliability. Performing a global data overview, we note that (a) ecological status can be characterized as good for the majority of the sites, especially for small mountain streams, and (b) the general trend in most cases is degradation of current conditions, related either to anthropogenic pressures or to human activity combined with natural factors. This database, in a more completed and enriched form, could assist in the implementation of 2000/60/EC Directive in Greece and the establishment of reference conditions of surface freshwater systems.

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Ecology of the Atlantic Forest

Ecology ◽

10.1093/obo/9780199830060-0233 ◽

2021 ◽

Author(s):

Elise Damstra ◽

Cristina Banks-Leite

Keyword(s):

Atlantic Forest ◽

Forest Cover ◽

Time Lag ◽

Native Forest ◽

Important Species ◽

Habitat Transformation ◽

Golden Lion Tamarin ◽

Palm Heart ◽

In The Wild ◽

Unique Domain

Extending along the southern coast of Brazil, into Argentina and Paraguay, the Atlantic Forest is a domain that once covered 150 Mha and includes many distinct forest subtypes and ecosystems. Its large latitudinal (29˚) and altitudinal (0–2,800 m above sea level) range, as well as complex topography in the region, has created microclimates within forest subtypes, which has led to biodiversity specifically adapted to narrow ecological ranges. The region is incredibly species-rich and is home to charismatic or economically important species such as the black and golden lion tamarin, the red-browned Amazon parrot, and the highly prized palm heart from Euterpe edulis. Through widespread human-driven change dating back to the arrival of European settlers in 1500, this realm has been extensively reduced, fragmented, and modified. Nowadays, this region is home to about 130 million people (60 percent of the Brazilian population) and is responsible for producing 70 percent of Brazil’s GDP, putting a strain on natural resources and providing challenges to conservation. Due to its high levels of endemic species coupled with a high threat of habitat loss and fragmentation, the Atlantic Forest has been identified as a “biodiversity hotspot.” Numerous studies have assessed the effects of habitat transformation on biodiversity and the consensus is that the majority of species are negatively affected. It is puzzling however that few species have actually gone extinct in the wild, even if some extinctions might have gone undetected. Extinctions do not immediately follow habitat change, there is often a time lag of many decades between habitat transformation and extinction. This may suggest that many species in the Atlantic Forest are “living deads,” as despite their presence the available habitat no longer supports their requirements. It also suggests that there is a window of opportunity to restoring the domain to avert extinctions before they are realized. Current research and policy actions are geared toward optimizing restoration and increasing the extent of native forest cover, bringing hope to the conservation of this unique domain.

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Nursery Cultural Techniques Facilitate Restoration of Acacia koa Competing with Invasive Grass in a Dry Tropical Forest

Forests ◽

10.3390/f11111124 ◽

2020 ◽

Vol 11 (11) ◽

pp. 1124

Author(s):

Douglass F. Jacobs ◽

Anthony S. Davis ◽

R. Kasten Dumroese ◽

Owen T. Burney

Keyword(s):

Forest Restoration ◽

Forest Cover ◽

Seedling Survival ◽

Tree Canopy ◽

Anthropogenic Activity ◽

Native Forest ◽

Forest Trees ◽

Acacia Koa ◽

Mean Values ◽

Kikuyu Grass

Anthropogenic activity has caused persistent and prominent losses of forest cover in dry tropical forests. Natural regeneration of forest trees in grazed areas often fails due to lack of seed sources and consumption by ungulates. To address this, the effective restoration of such sites often requires fencing and outplanting nursery-grown seedlings. In the degraded, dry forests of tropical Hawaii, USA, an additional challenge to restoration of native forest trees is the introduced kikuyu grass (Cenchrus clandestinus). This invasive, rapidly growing rhizomatous plant forms deep, dense mats. We studied the use of nursery cultural techniques to facilitate the establishment of koa (Acacia koa) seedlings outplanted amidst well-established kikuyu grass on a volcanic cinder cone on the dry, western side of Hawaii Island. Seedlings were grown four months in three container sizes (49, 164, 656 cm3) and with four rates (0, 4.8, 7.2, and 9.6 kg m−3) of 15–9–12 (NPK) controlled-release fertilizer incorporated into media prior to sowing. After 16 months in the field, seedling survival was > 80% for all treatments with two exceptions: the non-fertilized 49 cm3 (78%) and 164 cm3 (24%) containers. After 10 years, only these two treatments had significantly lower survival (35% and 10%, respectively) than the other treatments. One year following planting, none of the non-fertilized seedlings had transitioned to phyllodes from juvenile true leaves, regardless of container size. For the fertilized 656 cm3 container treatment, 78%–85% of seedlings had phyllodes, with mean values increasing by fertilizer rate. Phyllodes are known to confer greater drought resistance than true leaves in koa, which may help to explain the improved survival of fertilized trees on this relatively dry site. Overall, nursery fertilization was more influential on seedling height and diameter response than container size after outplanting. However, the largest container (656 cm3) with the addition of fertilizer, produced significantly larger trees than all other treatments during the early regeneration phase; early growth differences tended to fade at 10 years due to inter-tree canopy competition. Although koa is able to fix atmospheric nitrogen through rhizobium associations, our data confirm the importance of nursery fertilization in promoting regeneration establishment. Nursery cultural techniques may play an important role in forest restoration of dry tropical sites invaded by exotic vegetation.

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Impacts of deforestation on water balance components of a watershed on the Brazilian East Coast

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832014000400030 ◽

2014 ◽

Vol 38 (4) ◽

pp. 1350-1358 ◽

Cited By ~ 15

Author(s):

Donizete dos Reis Pereira ◽

André Quintão de Almeida ◽

Mauro Aparecido Martinez ◽

David Rafael Quintão Rosa

Keyword(s):

Water Balance ◽

Forest Cover ◽

East Coast ◽

Swat Model ◽

Native Forest ◽

Efficiency Coefficient ◽

Water Balance Components ◽

The Real ◽

Calibration And Validation ◽

Creek Watershed

The Brazilian East coast was intensely affected by deforestation, which drastically cut back the original biome. The possible impacts of this process on water resources are still unknown. The purpose of this study was an evaluation of the impacts of deforestation on the main water balance components of the Galo creek watershed, in the State of Espírito Santo, on the East coast of Brazil. Considering the real conditions of the watershed, the SWAT model was calibrated with data from 1997 to 2000 and validated for the period between 2001 and 2003. The calibration and validation processes were evaluated by the Nash-Sutcliffe efficiency coefficient and by the statistical parameters (determination coefficient, slope coefficient and F test) of the regression model adjusted for estimated and measured flow data. After calibration and validation of the model, new simulations were carried out for three different land use scenarios: a scenario in compliance with the law (C1), assuming the preservation of PPAs (permanent preservation areas); an optimistic scenario (C2), which considers the watershed to be almost entirely covered by native vegetation; and a pessimistic scenario (C3), in which the watershed would be almost entirely covered by pasture. The scenarios C1, C2 and C3 represent a soil cover of native forest of 76, 97 and 0 %, respectively. The results were compared with the simulation, considering the real scenario (C0) with 54 % forest cover. The Nash-Sutcliffe coefficients were 0.65 and 0.70 for calibration and validation, respectively, indicating satisfactory results in the flow simulation. A mean reduction of 10 % of the native forest cover would cause a mean annual increase of approximately 11.5 mm in total runoff at the watershed outlet. Reforestation would ensure minimum flows in the dry period and regulate the maximum flow of the main watercourse of the watershed.

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Native forests but not agroforestry systems preserve arbuscular mycorrhizal fungal species richness in southern Ethiopia

Mycorrhiza ◽

10.1007/s00572-020-00984-6 ◽

2020 ◽

Vol 30 (6) ◽

pp. 749-759

Author(s):

Zerihun Belay ◽

Mesele Negash ◽

Janne Kaseva ◽

Mauritz Vestberg ◽

Helena Kahiluoto

Keyword(s):

Land Use ◽

Species Richness ◽

Species Composition ◽

Arbuscular Mycorrhizal ◽

Soil Samples ◽

Southern Ethiopia ◽

Native Forest ◽

Native Forests ◽

Land Use Types ◽

The Impact

Abstract The rapid conversion of native forests to farmland in Ethiopia, the cradle of biodiversity, threatens the diversity of the arbuscular mycorrhizal fungi (AMF) pivotal to plant nutrition and carbon sequestration. This study aimed to investigate the impact of this land-use change on the AMF species composition and diversity in southern Ethiopia. Soil samples were collected from nine plots in each of three land-use types: native forest, agroforestry, and khat monocropping. The plots of the three land-use types were located adjacent to each other for each of the nine replicates. Three 10 × 10m subplots per plot were sampled. AMF spores were extracted from the soil samples, spore densities were determined, and species composition and diversity were evaluated through morphological analysis. Both spore density and species richness were statistically significantly higher in the native forest than in the agroforestry plots with no clear difference to khat, whereas the true diversity (exponential of Shannon–Wiener diversity index) did not differ among the three land-use types due to high evenness among the species in agroforestry. In total, 37 AMF morphotypes belonging to 12 genera in Glomeromycota were found, dominated by members of the genera Acaulospora and Glomus. The highest isolation frequency index (78%) was recorded for Acaulospora koskei from native forest. Consequently, the agroforestry system did not appear to aid in preserving the AMF species richness of native forests relative to perennial monocropping, such as khat cultivation. In contrast, the native forest areas can serve as in situ genetic reserves of mycorrhizal symbionts adapted to the local vegetative, edaphic, and microbial conditions.

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Preliminary results from the FARCE 2015 campaign: multidisciplinary study of the forest–gas–aerosol–cloud system on the tropical island of La Réunion

Atmospheric Chemistry and Physics ◽

10.5194/acp-19-10591-2019 ◽

2019 ◽

Vol 19 (16) ◽

pp. 10591-10618 ◽

Cited By ~ 3

Author(s):

Valentin Duflot ◽

Pierre Tulet ◽

Olivier Flores ◽

Christelle Barthe ◽

Aurélie Colomb ◽

...

Keyword(s):

Wind Shear ◽

Forest Cover ◽

Horizontal Resolution ◽

Cloud System ◽

Horizontal Wind ◽

La Réunion ◽

Aerosol Formation ◽

Mountain Slope ◽

Tropical Island ◽

Aerosol Cloud

Abstract. The Forests gAses aeRosols Clouds Exploratory (FARCE) campaign was conducted in March–April 2015 on the tropical island of La Réunion. For the first time, several scientific teams from different disciplines collaborated to provide reference measurements and characterization of La Réunion vegetation, volatile organic compounds (VOCs), biogenic VOCs (BVOCs), (bio)aerosols and composition of clouds, with a strong focus on the Maïdo mountain slope area. The main observations obtained during this 2-month intensive field campaign are summarized. They include characterizations of forest structure, concentrations of VOCs and precursors emitted by forests, aerosol loading and optical properties in the planetary boundary layer (PBL), formation of new particles by nucleation of gas-phase precursors, ice-nucleating particles concentrations, and biological loading in both cloud-free and cloudy conditions. Simulations and measurements confirm that the Maïdo Observatory lies within the PBL from late morning to late evening and that, when in the PBL, the main primary sources impacting the Maïdo Observatory are of marine origin via the Indian Ocean and of biogenic origin through the dense forest cover. They also show that (i) the marine source prevails less and less while reaching the observatory; (ii) when in the PBL, depending on the localization of a horizontal wind shear, the Maïdo Observatory can be affected by air masses coming directly from the ocean and passing over the Maïdo mountain slope, or coming from inland; (iii) bio-aerosols can be observed in both cloud-free and cloudy conditions at the Maïdo Observatory; (iv) BVOC emissions by the forest covering the Maïdo mountain slope can be transported upslope within clouds and are a potential cause of secondary organic aerosol formation in the aqueous phase at the Maïdo Observatory; and (v) the simulation of dynamics parameters, emitted BVOCs and cloud life cycle in the Meso-NH model are realistic, and more advanced Meso-NH simulations should use an increased horizontal resolution (100 m) to better take into account the orography and improve the simulation of the wind shear front zone within which lies the Maïdo Observatory. Using various observations and simulations, this work draws up an inventory of the in situ studies that could be performed in La Réunion and at the Maïdo Observatory. It also aims to develop scientific collaborations and to support future scientific projects in order to better understand the forest–gas–aerosol–cloud system in an insular tropical environment.

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Mineralisation of nitrogen in a chronosequence of rehabilitated bauxite mines

Soil Research ◽

10.1071/sr99047 ◽

2000 ◽

Vol 38 (2) ◽

pp. 435 ◽

Cited By ~ 15

Author(s):

M. C. L. Todd ◽

M. A. Adams ◽

P. F. Grierson

Keyword(s):

Native Forest ◽

N Availability ◽

N Mineralisation ◽

N Transformations ◽

Soil C ◽

Mine Site ◽

Native Forests ◽

Forest Sites ◽

Mine Sites ◽

Bauxite Mines

Mine site rehabilitation should aim to establish quickly and maintain the processes of nutrient cycling at rates comparable with, or approaching, those of native forests. Current management strategies for rehabilitating bauxite mines and other mine sites in Australia usually include planting fast-growing understorey species at high densities and applying fertiliser. We provide the first detailed study of nitrogen (N) availability and N transformations (mineralisation/immobilisation) in such rehabilitated mine sites. Mean concentrations of NO3– (0–5 cm) in a chronosequence (7, 13, 22, and 27 years old) of rehabilitated mine sites ranged from 0.5 to 1.3 kg/ha, and NH4+ from 4.0 to 9.5 kg/ha. In burnt and unburnt native jarrah (E. marginata Donn ex. Smith) forests adjacent to the mine site, mean NO3– concentrations in surface soil (0–5 cm) were 0.8 kg/ha (burnt) and 1.1 kg/ha (unburnt), and mean NH4+ concentrations were 6.8 kg/ha (burnt) and 7.8 kg/ha (unburnt). Concentration of NH4+ at 0–5 cm was strongly related to soil water content (R2 = 0.69, P < 0.05) in rehabilitation sites, but not at 5–10 cm depth. Rates of N mineralisation (0–5 cm) in rehabilitation sites ranged from 34 to 52 kg/ha.year, of the same order as rates in native forest soil. In all rehabilitation and native forest sites, rates of N mineralisation were significantly related to rates of N-uptake at both 0–5 and 5–10 cm depth (R2 > 0.63, P < 0.05). Soil C/N ratios (0–5 cm) in rehabilitation sites ranged from 22.4 to 38.8, and in native forests from 35.6 (burnt) to 40.3 (unburnt). Soil C/N ratios increased with depth in both rehabilitation and native forest sites (ranged from 31.2 to 51.6). Availability of water was the major determinant of nitrogen availability in this strongly Mediterranean climate.

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Turismo basado en naturaleza y conservación biológica: decisiones de uso de suelo en Mindo/ Nature-based tourism and biological conservation: land-use decisions in Mindo

Letras Verdes Revista Latinoamericana de Estudios Socioambientales ◽

10.17141/letrasverdes.23.2018.2861 ◽

2018 ◽

pp. 178-198

Author(s):

Jorje Ignacio Zalles

Keyword(s):

Land Use ◽

Forest Restoration ◽

Forest Cover ◽

Economic Incentive ◽

Natural State ◽

Biological Conservation ◽

Native Forest ◽

Land Use Patterns ◽

Use Patterns ◽

Land Use Decisions

El turismo basado en naturaleza se reconoce como un incentivo económico indirecto para la conservación biológica. En particular, se espera que las visitas dirigidas a observación de vida silvestre en estado natural aporten al establecimiento de patrones de uso de suelo favorables para la integridad biológica de los paisajes destino. La localidad de Mindo se ha consolidado en décadas recientes como receptora de turismo basado en naturaleza. Este artículo analiza el papel que juega el turismo en decisiones de uso de suelo tendientes al incremento de cobertura forestal nativa en Mindo. Se describe el marco institucional asociado al turismo y se elabora un mapa cognitivo de las decisiones de uso de suelo por participantes en un programa de restauración forestal. La mejora del atractivo turístico mediante restauración forestal es un importante factor de agencia individual en cuanto a uso de suelo en Mindo. Existen desafíos institucionales, sin embargo, que allí limitan el potencial del turismo como fuerza motriz para el incremento en cobertura forestal, y por ende su contribución a la conservación biológica en términos de paisaje. Abstract Nature-based tourism is recognized as an indirect economic incentive for biological conservation. In particular, the expectation is that visits aimed at the observation of wildlife in its natural state will encourage the establishment of land-use patterns that are favorable to the biological integrity of destination landscapes. The locality of Mindo has in recent decades become a well-known destination for nature-based tourism. This article analyzes the role played by tourism in land-use decisions aimed at increasing native forest cover in Mindo. The institutional framework associated with tourism is described, and a cognitive map of land-use decisions by participants in a forest restoration program is presented. The improvement of touristic attractiveness through forest restoration is an important influence on individual agency regarding land use in Mindo. There are institutional challenges, however, that limit tourism´s potential as a land-use driver for increased forest cover, and therefore its contribution to biological conservation at a landscape level.

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