292 research outputs found
Tingkat Dan Tipe Asosiasi Enam Jenis Paku Epifit Dengan Pohon Inang Di Taman Wisata Alam Gunung Meja Manokwari
Penelitian ini bertujuan untuk mengetahui tipe dan tingkat asosiasi antara enam jenis paku epifit dengan pohon inang di TWA Gunung Meja Manokwari. Metode yang digunakan adalah deskriptif dengan teknik survei sampling. Teknik sampling yang digunakan adalah pengambilang contoh sistematik. Data yang dikumpulkan adalah jumlah individu enam jenis paku epifit, dan jenis dan jumlah individu pada pohon inang. Tingkat asosiasi ditentukan berdasarkan indeks Jaccard dan indeks Dice. Sedangkan tipe asosiasi ditentukan menggunakan tabel kontingensi 2 x 2 melalui perbandingan nilai harapan dan nilai pengamatan. Hasil penelitian menunjukkann bahwa tingkat asosiasi antara paku epifit dan pohon inang bervariasi dari rendah sampai tinggi, dan sekitar 81,40% terjadi asosiasi positif dan 18,60% negatif. Asosia tertinggi terjadi antara Asplenium nidus L., dan Pometia coreaceae dan Pometia acuminata. Pyrrosia numularifolia dengan Cerbera floribunda, Decaspermum fruticosum dan Dracontomelum dao. Psilotum complanatum Sw., dengan Spathiostemon javensis. Faktor-faktor yang menentukan terjadinya asosiasi adalah distribusi pohon inang, tekstur batang, kekuatan batang dan alelopati
Does increasing crop heterogeneity benefit species diversity? Cross-taxon congruence across a gradient of agricultural landscapes
The congress theme reflected that landscape ecology is a meeting point - where pattern and process meet people and action - seen as a way of thinking when dealing with European landscapes. We wanted to put emphasis on the integration of pattern and process as a biophysical component of landscape ecology with people and action, bringing in the social and cultural approaches. This requires a true interaction of natural and social sciences, and of science, policy and practice. Therefore the congress was an opportunity to reflect on the state of the art of landscape ecology today. Furthermore, the challenge of the congress was what the future directions are of landscape ecology as a social relevant approach for science, policy and practice
Managing landscape spatio-temporal heterogeneity for biodiversity conservation
Although the concept of biodiversity emerged 30 years ago, patterns and processes influencing ecological diversity have been studied for more than a century. Historically, ecological processes tended to be considered as occurring in local habitats, spatially homogeneous and temporally at equilibrium. However, the increasing recognition of environmental heterogeneity and its role for biodiversity resulted in the emergence of landscape ecology, whose major goal is to understand how spatial and temporal heterogeneity influence biodiversity. To achieve this goal, researchers came to realize that a fundamental issue revolves around how they choose to conceptualize and measure heterogeneity. Indeed, observed landscape patterns and their apparent relationship with biodiversity often depend on the scale of observation and the model used to describe the landscape. Due to the strong influence of island biogeography, landscape ecology has been focusing primarily on spatial heterogeneity and the role of patch structure, patch context and mosaic heterogeneity for biodiversity. More recently, the increasing recognition of the role of temporal scale has led to the development of new conceptual frameworks acknowledging that landscapes are not only heterogeneous but also dynamic and that species and ecosystems respond to environmental changes with time lags. The current challenges now remain to truly integrate both spatial and temporal dimensions in studies on biodiversity and to understand how complex interconnections between social and ecological processes shape socio-ecological landscapes, maintain biodiversity and ecosystem services
RO4 : Nouveaux horizons pour lâĂ©cologie des paysages
LâĂ©cologie des paysages est une discipline relativement rĂ©cente qui sâest considĂ©rablement dĂ©veloppĂ©e au cours des trente derniĂšres annĂ©es (Turner and Gardner, 2015). Les paysages font aujourdâhui lâobjet dâun intĂ©rĂȘt institutionnel et politique important et croissant, ce qui contribue Ă renforcer la place de cette discipline. Par ailleurs, la disponibilitĂ© de nouvelles donnĂ©es spatialisĂ©es et les Ă©volutions des questionnements ouvrent de nouveaux horizons scientifiques qui nĂ©cessitent de mieux organiser la communautĂ© des chercheurs en Ă©cologie des paysages. Dans ce texte, nous rappelons les fondements et objectifs de lâĂ©cologie des paysages. Nous donnons quelques exemples de cette place plus grande offerte aux paysages dans le cadre des politiques environnementales et des accords internationaux sur le climat et le dĂ©veloppement durable. Puis nous abordons briĂšvement des exemples des nouvelles questions scientifiques auxquelles lâĂ©cologie des paysages cherche Ă rĂ©pondre. Enfin, nous concluons sur le rĂŽle que le groupe thĂ©matique dâĂ©cologie des paysages de la SFE pourra jouer dans ces dynamiques
Effect of farmland heterogeneity on multiple ES spatial variability and trade-offs
CongrĂšs international : « EcoSummit 2016 - Ecological Sustainability : Engineering Change » Ă Montpellier, France (29 Aout â 1er Septembre 2016) : 0072 Soil C, a double-win for food security and climate mitigation in low input agriculture : Lessons from temperate and tropical regions. Farmland heterogeneity has a true positive effect on biodiversity-in particular bee, bird, plant, spider. Positive effect on biological control -due to linear semi-natural elements. No effect on pollination and production. Complex interactions : Farmland heterogeneity Semi-natural percentage Practices Agricultural policies should start considering field configuration while maintaining semi-natural habitats and agrochemical reduction
Impacts of global change on species distributions: obstacles and solutions to integrate climate and land use
Aim The impact of multiple stressors on biodiversity is one of the most pressing questions in ecology and biodiversity conservation. Here we critically assess how often and efficiently two main drivers of global change have been simultaneously integrated into research, with the aim of providing practical solutions for better integration in the future. We focus on the integration of climate change (CC) and land-use change (LUC) when studying changes in species distributions. Location Global. Methods We analysed the peer-reviewed literature on the effects of CC and LUC on observed changes in species distributions, i.e. including species range and abundance, between 2000 and 2014. Results Studies integrating CC and LUC remain extremely scarce, which hampers our ability to develop appropriate conservation strategies. The lack of CC-LUC integration is likely to be a result of insufficient recognition of the co-occurrence of CC and LUC at all scales, covariation and interactions between CC and LUC, as well as correlations between species thermal and habitat requirements. Practical guidelines for the study of these interactive effects include considering multiple drivers and processes when designing studies, using available long-term datasets on multiple drivers, revisiting single-driver studies with additional drivers or conducting comparative studies and meta-analyses. Combining various methodological approaches, including time lags and adaptation processes, represent further avenues to improve global change science. Main conclusions Despite repeated claims for a better integration of multiple drivers, the effects of CC and LUC on species distributions and abundances have been mostly studied in isolation, which calls for a shift of standards towards more integrative global change science. The guidelines proposed here will encourage study designs that account for multiple drivers and improve our understanding of synergies or antagonisms among drivers
Effects of fire frequency on savanna butterfly diversity and composition: A preliminary study
Fire plays a major role in many biomes, is widely used as a management tool and is likely to be affected by climate change. For effective conservation management, it is essential to understand how fire regimes affect different taxa, yet responses of invertebrates are particularly poorly documented. We tested how different fire frequencies influence savanna butterfly diversity and composition by using a long-term savanna fire experiment initiated in 1954 in the Kruger National Park (South Africa). We compared butterfly abundance, species richness and community composition across three fire frequencies: high (burnt annually), medium (burnt triennially) and low (burnt twice in 60 years). Plots with high fire frequency hosted higher abundance than medium- or low-frequency plots. Fire frequencies did not affect species richness, but they led to distinct communities of butterflies. Our findings suggest that, in view of the three fire frequencies tested, a spatial diversity of fire frequencies may increase butterfly diversity at the landscape level in wet savannas. Managers may need to promote a greater diversity of fire frequencies by increasing fire frequency in some areas to provide habitat for species requiring high fire frequency, and by decreasing fire frequency in a large proportion of the landscape to provide fire refuges. This study provides new insights for butterfly conservation in savannas and highlights several knowledge gaps, which further studies should address for insect responses to be given adequate consideration in fire management strategies.Conservation implications: A spatial diversity of fire frequencies may increase butterfly diversity. Managers may need to promote a greater diversity of fire frequencies by increasing fire frequency in some areas to provide habitat for species requiring high fire frequency, and by decreasing fire frequency in other areas to provide fire refuges
Diversité végétale des prairies : Définition
Un dictionnaire accessible Ă tous. Son Ă©dition en ligne permet une consultation libre et gratuite. Sa structuration et son organisation offrent diffĂ©rents niveaux de lecture et en font un outil dynamique grĂące aux images, aux vidĂ©os, aux interviews dâauteur et aux infographies. Il sâagit Ă©galement dâun outil Ă©volutif qui doit permettre Ă dâautres acteurs et territoires de sâen emparer et de participer Ă son enrichissement en commentant les dĂ©finitions ou en proposant dâautres termes Ă dĂ©finir
STRUKTUR, KERAGAMAN DAN ASOSIASI KOMUNITAS TUMBUHAN PEMANJAT DENGAN POPULASI ALAM MERBAU DI TAMAN WISATA ALAM GUNUNG MEJA MANOKWARI-PAPUA BARAT (Structure, Diversity and Association of Climbing Plants Communities with Merbau Population in Gunung Meja)
ABSTRAKStruktur, keragaman dan asosiasi komunitas tumbuhan pemanjat dengan pohon inang di hutan tropis sangat ditentukan oleh banyak faktor biofisik habitat yang saling timbal balik hubungannya. Penelitian ini bertujuan untuk mengetahui struktur, keragaman dan derajat asosiasi antara tumbuhan pemanjat dengan tegakan alam merbau di TWA Gunung Meja Manokwari, Papua Barat. Hasil penelitian menunjukkan bahwa liana di bawah tegakan merbau memiliki keragaman sedang, terdiri dari 67 jenis, 52 genera dan 32 famili liana, liana berkayu 33 jenis, 29 genera dan 22 famili dan liana tak berkayu 35 jenis, 27 genera dan 19 famili. Jenis dominan adalah Pothos rumphii, dominansi sedang Philodendron sp. dan 65 jenis yang lain kurang dominan. Sebanyak 33 jenis berasosiasi sangat kuat dengan tegakan merbau, 28 jenis asosiasinya kuat dan 6 jenis asosiasinya kurang kuat. Faktor lingkungan yang berperan terhadap strukur dan keragaman serta asosiasi adalah struktur vertikal dan struktur horizontal tegakan, naungan hutan, diameter, tinggi, tekstur batang dan lebar tajuk pohon merbau dan jenis pohon yang lain.  ABSTRACTReciprocal relationship among biophysical factors of habitat influence the structure, diversity and assocition levels of climbing plants with host tree in the tropical forest. The aims of this study were to know structure, diversity and assocition levels of liana and merbau population in Gunung Meja natural tourism park of Manokwari, West Papua. There were 67 species, 52 genera and 32 families of climbing plants under the merbau stands. It consists of 33 species of lianas, 29 genera, 22 families, 35 species of vines, 27 genera and 19 families and they have medium diversity levels. Pothos rumphii is the most dominant species, Philodendron sp. is medium dominant and 65 species are minimum dominant. 33 species have strong association with merbau stands, 28 species has less strong and 6 were not strong. Habitat factors that plays an important roll in the structure, diversity and assocition levels of climbing plants, were vertical and horizontal structure of forest stands, shade levels, diameters, height, crown width, texture of merbau burk and other tree species
Woody cover in wet and dry African savannas after six decades of experimental fires
Fire is an integral process in savannas ecosystems as it alters the extent of woody cover in these systems. This study examined the effects of varying fire frequencies and fire exclusion over a 60-year time period in South Africa. The presence of fire, irrespective of frequency, was influential in lowering tree abundance in the wet savanna, whilst the effect of fire in the dry savanna was limited. This study suggests that vegetation responses to fire are most likely influenced by rainfall, thus it is recommended that management strategies should take account of whether a savanna is a wet or dry system when implementing fire management regimes
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