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1.
Heliyon ; 10(9): e30273, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38694028

RESUMO

The endangered and poorly known Swamp Grass-babbler, Laticilla cinerascens (Passeriformes: Pellorneidae), confronts critical threats and vulnerability due to its specific habitat requirements and restricted populations in the northeastern region of the Indian Subcontinent. This study investigates the distribution of the species, habitat quality, geometry and shape complexity of connectivity among the protected areas (PAs), and responses to climate change in Northeast India under different climate change pathways by utilizing ensemble distribution models, and ecological metrics. From the total distribution extent (1,42,000 km2), approximately 9366 km2 (6.59 %) is identified as the suitable habitat for this threatened species. Historically centered around Dibru Saikhowa National Park (DSNP), the species faced a drastic decline due to anthropogenic activities and alteration in land use and lover cover. The study also reveals a significant decline in suitable habitat for L. cinerascens in future climate scenarios, with alarming reductions under SSP126 (>10 % in the timeframe 2041-2060 and > 30 % from 2061 to 2080), SSP245 (>90 % in both time periods), and SSP585 (>90 % in both timeframes) from the present scenario. At present, DSNP has the most suitable habitat within the distribution range but is projected to decline (>90 %) under more severe climate change scenarios, as observed in other PAs. Landscape fragmentation analysis indicates a shift in habitat geometry, highlighting the intricate impact of climate change. It predicts a substantial 343 % increase (in the SSP126) in small habitat patches in the future. Connectivity analysis among PAs shows a significant shift, with a decline exceeding 20 %. The analysis of shape complexity and connectivity geometry reveals a significant increase of over 220 % in the fragmentation of connectivity among PAs between 2061 and 2080 under the SSP585 climate change scenario compared to the present conditions. The study underscores the urgent need for conservation actions, emphasizing the complex interplay of climate change, habitat suitability, and fragmentation. Prioritizing PAs with suitable habitats and assessing their connectivity is crucial. Adaptive management strategies are essential to address ongoing environmental changes and safeguard biodiversity. Future research in critical areas is needed to establish long-term monitoring programs to lead/extend effective conservation strategies.

2.
Biology (Basel) ; 12(3)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36979074

RESUMO

Wildlife corridors that connect mosaic habitats in heterogeneous mountainous landscapes can be of high significance as they facilitate the genetic and demographic stability of free-ranging populations. Peripheral populations of widespread species are usually ignored in conservation planning. However, these populations retain locally common alleles and are genetic reservoir under the changing climatic conditions. Capra sibirica has widespread distribution, and its southern peripheral population is distributed in the Indian trans-Himalayan region (ITR). In the present study, we studied the spatial distribution and genetic make-up of Himalayan ibex from the ITR following the landscape genetics approach. We obtained 16 haplotypes at the mitochondrial d-loop region and found a stable demography in the past with a recent decline. With 10 nuclear microsatellites, we ascertained 111 unique individuals assigned into two clusters following Bayesian and non-Bayesian clustering analysis with several admixed individuals. We also recorded 25 first-generation migrants that reflected relatively high dispersal and gene-flow across the range. We identified a 19,835 sq.km suitable area with 13,311 sq.km in Ladakh and 6524 sq.km in Lahaul-Spiti. We identified a novel movement corridor for Himalayan ibex across the Lahaul-Zanskar-Sham valley (L-Z-SV) that displayed a fairly good conductance with low genetic divergence among the samples collected on the L-Z-SV corridor. We propose declaring a protected area in the Lahaul and Kargil districts to prioritize dedicated conservation efforts for the Himalayan ibex and other sympatric ungulates that impart a major role in the diet of large carnivore and balancing ecosystem services in the trans-Himalayan region.

3.
Folia Primatol (Basel) ; 91(6): 595-609, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32599590

RESUMO

We used mitochondrial DNA to examine gene flow in a region of western Uganda that has received little attention regarding chimpanzee population dynamics. The area is critical to gene flow between isolated Democratic Republic of Congo populations and the rest of East Africa. None of the chimpanzees in each of the 4 protected areas under consideration (Toro-Semliki Wildlife Reserve, Semuliki National Park, Rwenzori Mountains National Park and Itwara Central Forest Reserve) are fully habituated. Therefore, it is not clear whether one or more populations have historically used this fragmented landscape for (1) regular ranging and/or (2) infrequent dispersal. We incorporated the published sequences of the first hypervariable region of the D-loop of the mitochondrial genome from 3 previously sampled sites (n = 39) while also contributing the first extensive genetic sampling of chimpanzees in Toro-Semliki (n = 80). Our goal was to generate a historical baseline model of metapopulation dynamics in this region and determine which, if any, of these protected areas forms a fragmented landscape for a single chimpanzee population. According to a discriminant analysis of principal components, the haplotypes at Toro-Semliki form a central cluster, and Itwara is its nearest genetic neighbor. Rwenzori Mountains National Park is the most distant neighbor of all protected areas. We performed an analysis of molecular variance for 14 different population models that divided the samples from the 4 protected areas into 2, 3 or 4 populations. The best fit model included 3 populations: Toro-Semliki Wildlife Reserve and Itwara Forest Reserve comprised a single population; Semuliki National Park and Rwenzori Mountains National Park formed 2 additional separate populations (variance among = 9%, p = 0.014). The results indicated that some protected areas comprised distinctive populations, while others formed a fragmented landscape for a population's ranging for foraging purposes. Therefore, the edges of a protected area do not always define a chimpanzee population. We propose a closer examination of those dynamics through renewed sampling. Advances in DNA extraction and next-generation sequencing will allow us to compare thousands of single nucleotide polymorphisms in the genomes of unhabituated chimpanzees living in each of these protected areas.


Assuntos
Fluxo Gênico , Pan troglodytes/genética , Dinâmica Populacional , Animais , Conservação dos Recursos Naturais , DNA Mitocondrial , Genética Populacional , Haplótipos/genética , Comportamento de Retorno ao Território Vital , Uganda
4.
Rev. biol. trop ; 67(4)sept. 2019.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1507560

RESUMO

Este artículo es una revisión bibliográfica sobre las funciones ecológicas que caracterizan a los bambúes, por las cuales merecen un mayor reconocimiento e inclusión en los programas de restauración ecológica. Los bambúes son un grupo de plantas muy diverso, de amplia distribución geográfica y económicamente importante. Aunque son más reconocidos por los usos comerciales, su potencial de uso en programas de restauración ecológica es prometedor, ya que pueden ser eficientes en la prestación de varios servicios ambientales relacionados con el suelo, el agua y el secuestro de carbono. Su rápido crecimiento, junto con su capacidad para controlar la erosión y mantener el agua a nivel del suelo, así como para proporcionar nutrientes mediante la descomposición de la hojarasca, convierte a los bambúes en un grupo valioso para la recuperación de áreas degradadas y para la restauración productiva de ecosistemas, en particular a través de sistemas agroforestales. Los enfoques agroforestales pueden combinar diferentes especies de bambú con otros cultivos, para satisfacer las necesidades humanas y generar a la vez beneficios para los ecosistemas. De manera similar, los bosques o plantaciones de bambúes, junto con sistemas agroforestales mixtos, pueden actuar como áreas de conexión y corredores biológicos, en paisajes muy fragmentados, proporcionando refugio y alimento para una amplia diversidad de organismos. A pesar de las percepciones de que los bambúes pueden ser invasivos, las pruebas para apoyar esto son limitadas. Recomendamos una evaluación cuidadosa de las características biológicas de las especies de bambúes seleccionadas, antes de su implementación en proyectos de restauración productiva y de recuperación de los servicios ambientales.


This article is a bibliographic review on the ecological functions that distinguish bamboos, for which they deserve greater recognition and inclusion in ecological restoration programs. Bamboos are a highly diverse, geographically widespread and economically important plant group. Although they are more recognized by commercial uses, their potential for use in ecological restoration programs is promising, as they can be effective in delivery of several environmental services related to soil, water and carbon sequestration. Their rapid growth, along with their abilities to control erosion and maintain water at soil level, as well as provide nutrients by litterfall decomposition, make them a valuable group for recovery of degraded areas and in productive restoration of ecosystems, in particular via agroforestry systems. Agroforestry approaches can combine different bamboo species with other crops, to meet human needs while generating benefits for ecosystems. Similarly, bamboo forests or plantations together with mixed agroforestry systems can act as stepping-stones and biological corridors, in very fragmented landscapes by providing shelter and food for a wide diversity of organisms. Despite perceptions that bamboos can be invasive, evidence to support this is limited. We recommend careful evaluation of the biological characteristics of bamboo species selected, prior to deployment in productive restoration projects and for the recovery of environmental services.

5.
Ecol Evol ; 3(9): 2917-32, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24101983

RESUMO

Climate change is a threat to biodiversity, and adaptation measures should be considered in biodiversity conservation planning. Protected areas (PA) are expected to be impacted by climate change and improving their connectivity with biological corridors (BC) has been proposed as a potential adaptation measure, although assessing its effectiveness remains a challenge. In Mesoamerica, efforts to preserve the biodiversity have led to the creation of a regional network of PA and, more recently, BC. This study evaluates the role of BC for facilitating plant dispersal between PA under climate change in Mesoamerica. A spatially explicit dynamic model (cellular automaton) was developed to simulate species dispersal under different climate and conservation policy scenarios. Plant functional types (PFT) were defined based on a range of dispersal rates and vegetation types to represent the diversity of species in the region. The impacts of climate change on PA and the role of BC for dispersal were assessed spatially. Results show that most impacted PA are those with low altitudinal range in hot, dry, or high latitude areas. PA with low altitudinal range in high cool areas benefit the most from corridors. The most important corridors cover larger areas and have high altitude gradients. Only the fastest PFT can keep up with the expected change in climate and benefit from corridors for dispersal. We conclude that the spatial assessment of the vulnerability of PA and the role of corridors in facilitating dispersal can help conservation planning under a changing climate.

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