Conservation Of Tree Diversity Research Articles

The Global Tree Assessment provides a multifaceted view on the future of tree diversity conservation

The Global Tree Assessment provides a multifaceted view on the future of tree diversity conservation

Patterns of shade plant diversity in four agroforestry systems across Central America: a meta-analysis

Agroforestry systems can potentially increase tree diversity within agricultural landscapes, but to date, there is little understanding of the patterns of shade plant diversity within different agroforestry systems (AFS) at large spatial scales. Using compiled plant inventory data (from 23 sources, 2517 plots, and 148,255 individuals) encompassing four AFS (shaded coffee; shaded cocoa; dispersed trees on pastures; and live fences) across six countries in Central America we estimated different metrics of diversity to assess the conservation value of different AFS for shade plants. 458 shade plant species were recorded across the four agroforestry systems. Primary forest species accounted for 28% of the shade species recorded, but only 6% of the recorded individuals. No single AFS was consistently the most diverse across countries when considering rarefied species richness. Trees on pastures can potentially reach a similar species richness as cocoa and coffee systems but require sampled areas 7–30 times larger. In terms of composition, 29 species were shared across the agroforestry systems in different countries, illustrating the strong selection pressure of farmers for species that provide timber, firewood, and fruit. Our study highlights the potential contribution and limitations of different AFS for tree diversity conservation within agricultural landscapes.

Stand Structure Management and Tree Diversity Conservation Based on Using Stand Factors: A Case Study in the Longwan National Nature Reserve

The management of stand structure and the protection of species diversity are crucial to forest ecosystem service functions. Changbai Mountain is one of the three major forest regions in Northeast China, and understanding the characteristics of stand structure and the allometric relationship between stand structure variables and the correlation between stand factors and species diversity is the basis for achieving effective forest management and ecological function improvement. In this study, the typical deciduous broad-leaved mixed forest and coniferous and broad-leaved mixed forest of the Longwan Nature Reserve in the Changbai Mountain were taken as the research objects, and the stand structure and diversity were investigated in detail. Allometric growth equations were established using the breast height diameter (DBH), tree height, and crown width of the main dominant species. Pearson correlation analysis was conducted on the stand structure and diversity of the forest community. The experimental results showed that young forests with small diameters and small individuals were the main part of the stands. Optimal allometric growth models of the main tree species (Acer mandshuricum, Ulmus davidiana var. japonica, Juglans mandshurica, Acer mono, and Tilia amurensis) were 0.807D0.646, 0608D0.381H0.390, 0.502D0.533H0.295, 0.795D0.540H0.157, and 0.541D0.484H0.301, respectively, with R2 values ranging between 0.6 and 0.8, indicating a good fit for the models. Furthermore, tree density, crown width, and DBH were the main factors affecting tree diversity. The research results will provide theoretical support for the efficient management of forest stand structure and diversity conservation in the Longwan Reserve.

Urban Parks in Curitiba as Biodiversity Refuges of Montane Mixed Ombrophilous Forests

The assessment of the conservation status of urban forest remnants is essential for sustaining tree diversity in metropolitan cities. This study evaluated the composition and structure of forest remnants in four urban parks within the natural distribution of Montane Mixed Ombrophilous Forest in Curitiba (PR, Brazil). We allocated 66 plots of 100 m2 and recorded all trees with perimeters at breast height ≥ 15 cm. A total of 1256 individuals from 44 botanical families and 117 tree species were identified, of which three are alien species. Tree density ranged from 1670 to 2095 trees ha−1, while the density of standing dead trees varied between 90 and 188 trees ha−1. We experienced values for the Shannon diversity index between 3.00 and 3.52 nats ind−1, which are comparable to the values for other non-urban forest remnants. Non-pioneer species represented 84.6% of the tree community (99 spp.), and 76% were zoochoric species (89 spp.). The research findings feed the discussion on the need of specific and integrated measures for the management of the urban parks reserved to the conservation of tree diversity in a specific phytoecological formation, while considering aspects of climate change and historical anthropisation.

Phytosociological analysis on Kamarajumetta SacredGroves of Hukumpeta Mandal in VisakhapatnamDistrict, Andhra Pradesh, India

Phyto-sociological studies were conducted on Kamarajumetta sacred grove in Hukumpeta Mandal of Visakhapatnam District, for analysis of tree species diversity in the year 2017-2018. Local community initiations are more effective management system than the government management system for tree diversity conservation, in sacred groves of Visakhapatnam. In Kamarajumetta Sacred Groves are small in size and can act as starting points for any long term conservation plan of biodiversity. The communities have kept their faith and traditions linked to these mini nuclei of rich biodiversity in the landscape. Therefore, anyconservation program can begin from local communities, by taking them into consideration as trustworthy awareness building factors.

Biodiversity–productivity relationships are key to nature-based climate solutions

The global impacts of biodiversity loss and climate change are interlinked, but the feedbacks between them are rarely assessed. Areas with greater tree diversity tend to be more productive, providing a greater carbon sink, and biodiversity loss could reduce these natural carbon sinks. Here, we quantify how tree and shrub species richness could affect biomass production on biome, national and regional scales. We find that GHG mitigation could help maintain tree diversity and thereby avoid a 9–39% reduction in terrestrial primary productivity across different biomes, which could otherwise occur over the next 50 years. Countries that will incur the greatest economic damages from climate change stand to benefit the most from conservation of tree diversity and primary productivity, which contribute to climate change mitigation. Our results emphasize an opportunity for a triple win for climate, biodiversity and society, and highlight that these co-benefits should be the focus of reforestation programmes. Exploring how biodiversity and climate change are interlinked, the authors show that limiting warming could maintain tree diversity, avoiding primary productivity loss. Countries with greater climate change economic costs benefit most: a potential triple win for climate, biodiversity and society.

Critical ecological thresholds for conservation of tropical rainforest in Human Modified Landscapes

In the tropics, human modified landscapes (HMLs) emerge as potential areas where important levels of biodiversity, ecosystem functions, and services can be conserved. Yet, it is unknown which landscape structures may enable this goal. We studied how tree diversity (SD), aboveground biomass (AGB) and aboveground carbon storage (ACS) change across a gradient of forest-to-agriculture conversion process (0 to ~100%). We addressed following questions: i) How SD, AGB and ACS change with landscape composition and configuration, as the forest-to-agriculture conversion advances? ii) Do such changes depend on the spatial scale of the landscapes, iii) Are there thresholds of forest habitat loss after which SD, AGB and ACS collapse? iv) If so, what explains such response? Changes in landscape composition, but not in configuration, explained the SD, ABG, ACS variability across the deforestation gradient. Percentage of forest cover was the best predictor of such variation, independently the landscape spatial scale. SD declined convexly, showing a critical collapse threshold, as forest loss advanced. AGB and ACS decreased exponentially with a 50% of reduction at ~30% of forest loss. Elimination of several rare species with high contributions to AGB explained the exponential decrease of AGB and ACS. We accord with previous studies targeted in other assemblages and forest trees variables that maintaining >40% of forest is critical for tree diversity conservation. We broaden this estimation by alerting that ecosystem functions (e.g., AGB) and services (e.g., ACS) reduce with deforestation in a faster way than biodiversity. This exemplifies that different ecosystem attributes are affected differentially by deforestation, adding a strong challenge for conservation in HML.

Tree Diversity Conservation Initiatives in Sacred Groves of Kathmandu Valley, Nepal

The study was conducted in two sacred groves of Kathmandu Valley, Pashupati Sacred Grove, and Bajrabarahi Sacred Grove, aiming to analyze the diversity of tree species and their role in conserving biodiversity. Parallel transects with concentric circular plot survey methods were applied for data collection. During the study, 23 tree species belonging to 22 genera and 15 families were recorded in Pashupati sacred grove, whereas only 19 tree species belonging to 16 genera and 13 families were recorded from Bajrabarahi Sacred Grove. The Shannon-Weiner diversity indices were higher (H=1.91) in Pashupati Sacred Grove compared to Bajrabarahi Sacred Grove, with 1.80 Shanon-Weiner Indices. Three types of forest were recorded from Pashupati Sacred Grove, namely the Schima-Pyrus forest, Myrsine-Persea forest, and Quercus-Myrsine forest, and only one Neolitsiacuipala forest from Bajrabarahi Sacred Grove. The sacred grove is one of the pioneers and community-based management regimes of the forest resource management system. It plays a decisive role in biodiversity conservation as it associated with many taboos and belief systems, thus providing a better opportunity for conservation compared to that of the government management system.

Effect of forest management on tree diversity in temperate ecosystem forests in northern Mexico.

An important challenge for silvicultural practices is the conservation of tree diversity while fulfilling the traditional objectives of forest management, most notably timber harvesting. The purpose of this study was to compare the tree diversity before and after the application of silvicultural treatments in a temperate forest in northern Mexico. Fifteen experimental plots, each measuring 2500 m2, were established to evaluate the immediate effect of four silvicultural treatments. These treatments were identified by their levels of management: intensive (clearcut, removal 100%), semi-intensive (removal of 59–61% of basal area), conservative (removal of 29–31% of basal area), and a control group. New forest guidelines, in contrast to conventional approaches, were applied to the semi-intensive and conservative treatments based on health and diversity conditions. Basal area, canopy cover, tree and total volume were measured in each plot. The Importance Value Index, alpha diversity, and evenness were estimated before and after treatments. Eighteen species belonging to five genera and five families were found in the study area. The species with the highest ecological values were Pinus durangensis, P. teocote, Quercus sideroxyla, and Quercus convallata with IVI numbers between 13.6 and 24.5%. Alpha diversity was intermediate (Margalef: 2.9 to 3.8), while dominance and evenness were above average compared to other studies (Simpson: 0.69 to 0.77; Shannon-Wiener: 1.44 to 1.6; Pielou: 0.76 to 0.85). The species evenness index in the conservative treatment was high (Sorensen, Jaccard, quantitative Sorensen and Morisita-Horn; 88 to 99%), although abundance decreased. Overall, there were no significant differences in IVI values and diversity indicators before and after treatments, with the exception of the clearcut treatment. When associating the diversity indices with stand variables, only the Pielou’s evenness index showed a significant relationship between them. We concluded that both the conservative and semi-intensive treatments did not generate significant changes in tree diversity, but the former had slightly higher alpha diversity indices. These results can provide a better insight on silvicultural practices and their effects on species composition.

Buddha Bihar (Kiyang) based traditional model for tree diversity conservation in Rangamati Hills, Bangladesh

This paper describes Buddha Bihar (Kiyang) based biodiversity conservation of Nirbanpur in Rangamati Hill District of Bangladesh. Rangamati is the native of the tribal people specially the Chakma and they are the followers of the Bhudda religion. This Bihar comprised of 300 acres of hilly land and maintaining natural patches having 76 indigenous tree species. Most of the tribal people of this district belong to Buddha religion and they strongly believe in the biodiversity conservation around their religious institute and most of them are situated at hill top of the deep forest areas. This institution is maintained by the religious leaders locally called as Bantheya and the local community people have great respect for them. Most of the Bantheyas are conserving biodiversity in traditional way which is unique model for local level biodiversity conservation and local people also consider these plants as taboos or secrete trees. Bihar management committee maintains some traditional rules in plant conservation, but now they are leaned towards commercial plantation. BFRI scientists try to motivate them towards plantation indigenous species by awareness meeting. The seedlings of 32 indigenous tree species were planted in the Bihar area which has enhanced the diversity of flora and fauna. A biodiversity conservation model having four pillars has been developed on consultation with the community and religion leaders. The theme of pillars are land tenure, traditional knowledge, awareness and support. Bihar based biodiversity conservation effort has created a new avenue for wildlife and bird conservation. A list of existing plants species around Nirbanpur Bihararea has been given.J. Biodivers. Conserv. Bioresour. Manag. 2018, 4(1): 27-34

Tree Diversity and Uses in Coffee Plantations of a Mixe Community in Oaxaca, Mexico

Indigenous communities manage shaded coffee (Coffea arabica) plantations by applying traditional practices which promote and conserve forest structure and tree diversity while providing a wide variety of environmental services, as well as social and cultural functions. We studied coffee production by a Mixe indigenous community in the Mixe mountains region of Oaxaca, Mexico, to identify the relationship between traditional management of coffee plantations and tree diversity conservation through the analysis of forest structure, richness, composition, and tree uses. A total of 85 tree species were recorded in three classified coffee production areas, the majority of which were natives. Seven species use categories were identified. The results demonstrate variations in coffee plantation structure according to topographic conditions, distance to the community, and management practices. Norms, traditions, and customs of the community guide coffee plantation management. The tree diversity registered in coffee plantations and in uncultivated medium tropical deciduous forest contributes to the maintenance of forest diversity. Thus, traditional coffee management promotes biodiversity conservation. In this particular case, the local community conserves medium tropical deciduous forest within its coffee plantations.

The Role of Coffee Based Agroforestry System in Tree Diversity Conservation in Eastern Uganda

Abstract Agroforestry farming system comprises considerable cultivated land area in the tropics. Despite the economic and social benefits of the system for farmers, it is also known to have an important role in the conservation of tree species. This study aims to evaluate the composition and distribution of tree species in coffee based agroforestry system to determine the potential for biodiversity conservation. To address the objective of this study, 57 sample plots in farmers’ coffee field and 12 sample plots in forest reserve were surveyed in Eastern Uganda. The result shows that the number of indigenous tree species in coffee farms was lower than that of forest reserve. Similarly, tree species richness per plot, Shannon and Simpson diversity indexes of forest reserve were significantly (p≤0.05) higher than that of coffee farms. However, with the inclusion of exotic tree species, coffee farms were found to be significantly higher than that of forest reserve for the above diversity indexes. On the other hand, the distribution of tree species in the coffee farms were mainly dominated by few tree species indicating the need for measures that ensure the sustainability of those less represented tree species.

Farmers’ contributions to the conservation of tree diversity in the Groundnut Basin, Senegal

Tree diversity in West Africa is threatened by intensified land uses and salinization, and farmers’ role in conservation of tree species is unclear. We hypothesized that farmers contribute to conservation of tree diversity through protection of trees in their agroforestry landscapes and compared the diversity and structure of the tree vegetation across landscape classes. Inventories were carried out in three villages in the Groundnut Basin in Senegal, assessing tree diversity, density and crown cover. Tree diversity as assessed by species accumulation curves was high in forests, but cultivated landscapes had comparable or almost comparable diversity, especially in the cases where the forest was planted or was affected by charcoal production. However, the occurrence of exotic species was higher in cultivated parts of the landscape, and although many species were in common, ordination plots indicated that forests and cultivated landscapes to some degree had different species composition. Salinity had a strong influence on vegetation, not only in the tans (salt marshes) but also across the other landscape classes. In conclusion, agroforestry landscapes in the three villages harbor considerable tree diversity, but insufficient to fully conserve the tree species. We argue that informing and including farmers in tree management in the region will contribute to overall conservation of tree genetic resources.

Spatial congruence between carbon and biodiversity across forest landscapes of northern Borneo

Understanding how carbon and biodiversity vary across tropical forest landscapes is essential to achieving effective conservation of their respective hotspots in a global context of high deforestation. Whether conservation strategies aimed at protecting carbon hotspots can provide co-benefits for biodiversity protection, and vice versa, highly depends on the extent to which carbon and biodiversity co-occur at the landscape level. We used field measurements and easily accessible explanatory variables to model aboveground carbon density, soil carbon density and tree alpha diversity (response variables) over a mostly forested area of northern Borneo. We assessed the spatial relationships between response variables and the spatial congruence of their hotspots. We found a significant positive relationship between aboveground carbon density and tree alpha diversity, and an above-than-expected-by-chance spatial congruence of their hotspots. Consequently, the protection of areas of high aboveground carbon density through financial mechanisms such as REDD+ is expected to benefit tree diversity conservation in the study area. On the other hand, relationships between soil carbon density and both aboveground carbon density and tree alpha diversity were negative and spatial congruences null. Hotspots of soil carbon density, mostly located in peatlands, therefore need specific conservation regulations, which the current moratorium on peat conversion in Indonesia is a first step toward.

Phyto-sociological Assessment of Sacred Groves in Kathmandu, Nepal

Phyto-sociological studies were conducted in Bajrabarahi and Pashupati Sacred Groves of Kathmandu, Nepal for the comparative analysis of tree species diversity in the year 2012-2013. Concentric circular plots with radius of 20m were used to collect necessary information along four and eight parallel transects in Bajrabarahi and Pashupati Sacred Groves, respectively. Similarity Index showed that more than 57% tree species are shared by both the groves whereas Maturity Index showed that Bajrabarahi Sacred Grove has more mature trees (33.9) than Pashupati Scared Grove (26). Based on Importance Value Index three different forest types, namely - Schima-Pyrus, Myrsine-Persea and Quercus-Myrsine, were identified in Pashupati Sacred Grove whereas, Bajrabarahi Sacred Grove incorporated only one forest type of Neolitsea cuipala. The ShannonWeiner Species Diversity Index, Evenness and number of tree species of Pashupati Sacred Grove was higher than that of Bajrabarahi Sacred Grove, whereas the canopy coverage of Bajrabarahi Sacred Grove was higher than Pashupati Sacred Grove. Local community initiations are more effective management system than the government management system for tree diversity conservation, in sacred groves of Kathmandu.

Spatial incongruence among hotspots and complementary areas of tree diversity in southern Africa

AbstractAimBiodiversity hotspots have important roles in conservation prioritisation, but efficient methods for selecting among them remain debated.LocationSouthern Africa.MethodsIn this study, we used data on the dated phylogeny and geographical distribution of 1400 tree species in southern Africa to map regional hotspots of species richness (SR), phylogenetic diversity (PD), phylogenetic endemism (PE), species endemism (CWE), and evolutionary distinctiveness and global endangerment (EDGE). In addition, we evaluated the efficiency of hotspots in capturing complementary areas of species richness and phylogenetic diversity. We examined the spatial overlap among hotspots for each metric, and review how well one metric may serve as a surrogate for others. We then evaluated the effectiveness of current conservation areas in capturing these different facets of diversity and complementary areas. Lastly, we explored the environmental factors influencing the distribution of these diversity metrics in southern Africa.ResultsWe reveal large spatial incongruence between biodiversity indices, resulting in unequal representation of PD, SR, PE, CWE and EDGE in hotspots and currently protected areas. Notably, no hotspot area is shared among all five measures, and 69% of hotspot areas were unique to a single diversity metric. Areas selected using complementarity are even more dispersed, but capture rare diversity that is overlooked by the hotspot approach.Main conclusionsAn integrative approach that considers multiple facets of biodiversity is needed if we are to maximise the conservation of tree diversity in southern Africa.

Conserving tropical tree diversity and forest structure: the value of small rainforest patches in moderately-managed landscapes.

Rainforests are undergoing severe deforestation and fragmentation worldwide. A huge amount of small forest patches are being created, but their value in conserving biodiversity and forest structure is still controversial. Here, we demonstrate that in a species-rich and moderately-managed Mexican tropical landscape small rainforest patches (<100 ha) can be highly valuable for the conservation of tree diversity and forest structure. These patches showed diverse communities of native plants, including endangered species, and a new record for the country. Although the number of logged trees increased in smaller patches, patch size was a poor indicator of basal area, stem density, number of species, genera and families, and community evenness. Cumulative species-area curves indicated that all patches had a similar contribution to the regional species diversity. This idea also was supported by the fact that patches strongly differed in floristic composition (high β-diversity), independently of patch size. Thus, in agreement with the land-sharing approach, our findings support that small forest patches in moderately-managed landscapes should be included in conservation initiatives to maintain landscape heterogeneity, species diversity, and ecosystem services.

The role of coffee agroforestry in the conservation of tree diversity and community composition of native forests in a Biosphere Reserve

Agroforestry is considered a promising alternative to conventional agriculture that can both conserve biodiversity and support local livelihoods. Coffee agroforestry may be particularly important for sustaining trees of conservation concern and late-successional stage, but this possibility remains unclear. Here, we examined whether coffee agroforestry systems can serve as conservation reservoirs of tree species native to nearby forests. We compared tree diversity, composition and structure between coffee agroforests and forests in La Sepultura Biosphere Reserve in Chiapas, Mexico. We found that, although at the landscape level the full set of coffee agroforests appears to conserve comparable tree species richness to nearby native forests, the species composition that is being conserved is different. Coffee agroforests had a lower proportion of trees of conservation concern, a higher proportion of pioneer trees, were dominated by Inga spp., harbored lower tree species diversity at the plot level, and were composed of different tree species compared to native forests. We suggest that conservation practitioners and policy makers seeking to promote coffee agroforestry as a conservation strategy should consider how such agroforestry systems differ in species diversity and composition from the native forests of conservation interest. Further, promoting different coffee agroforest management strategies, such as discouraging the replacement of diverse agroforest canopies with Inga-dominated canopies, would help improve the conservation value of coffee agroforests through more sustainable practices.

Does designation of protected areas ensure conservation of tree diversity in the Sudanian dry forest of Burkina Faso?

AbstractThe importance of conservation status of the forest (protected versus unprotected) at two sites with differing human population density (high versus low) on the tree diversity of a Sudanian dry forest in Burkina Faso was studied. All woody species were recorded in 127 circular plots (area = 456.16 m2), and density, dominance, frequency, importance value indices and a variety of diversity measures were calculated to assess the species composition, structure and heterogeneity. A total of 69 species, representing 26 families and 52 genera, were found. Combretaceae, Leguminosae subfamily Caesalpinioideae and Rubiaceae were the dominant families. Neither human pressure nor forest conservation status significantly influenced the tree species richness. Stem density and basal area were significantly higher at the site with high population density than otherwise. Fisher’s diversity index revealed the unprotected forest at the site with low population density as the most diverse. We identified species with high conservation importance that should be enriched to maintain a viable population size. In conclusion, the current designation of protected areas seems inefficient at ensuring the conservation of tree diversity in the forest reserve. Thus, participatory conservation programme should be initiated.

Effects of pasture management on the natural regeneration of neotropical trees

Summary Natural regeneration of forest trees in grazed pastures could potentially contribute to the conservation of tree diversity within the fragmented and agricultural landscapes that dominate much of the tropics. To understand this potential, we evaluated the effects of several widely used pasture management practices on tree regeneration in pastures in a tropical dry forest (subhumid) region of central Nicaragua. Species richness, density, diversity and composition of seedlings, saplings and adult trees were compared in 46 pastures under different management conditions. The management conditions included three different types of grasses (Brachiaria spp., Cynodon spp. and naturalized pastures) and two categories of fire history (recently burnt and not recently burnt). Thirty‐seven of the 85 tree species present in the pastures were regenerated under the current management conditions. The remaining 48 species may have had reduced natural regeneration because of limitations in either germination, dispersal, establishment or growth, as well as because of negative effects of pasture management practices. The richness, density and species composition of tree seedlings within pastures were explained by grass species composition, the density and richness of adult trees, cattle management and the distance of the pasture to forest. In contrast, no clear effect of fire history was found. Synthesis and applications. Current management practices allow the regeneration of almost half of the tree species in grazed pastures. However, to enhance the regeneration of species that show limited regeneration, management strategies, such as the retention of adult trees, protection of saplings and seedlings from weeding and grazing and use of enrichment plantings, may be necessary. These changes in pasture management would help contribute to the long‐term conservation of tree diversity within agricultural landscapes across the tropics.