Demography of Simakobu (Simias concolor) and the Impact of Human Disturbance

2012 ◽  
Vol 74 (6) ◽  
pp. 580-590 ◽  
Author(s):  
WENDY M. ERB ◽  
CAROLA BORRIES ◽  
NURUL S. LESTARI ◽  
THOMAS ZIEGLER
Keyword(s):  
Human Disturbance ◽  
Simias Concolor ◽  
The Impact

Changes in escape behaviour of black iguanas (Ctenosaura similis) over an anthropogenic disturbance gradient

Behaviour ◽  
2021 ◽  
pp. 1-21
Author(s):  
Pooja Panwar ◽  
Pilar Angélica Gómez-Ruiz ◽  
Matthew N. Zipple ◽  
Luis Sandoval
Keyword(s):  
Human Disturbance ◽  
Protected Area ◽  
Anthropogenic Disturbance ◽  
Escape Behaviour ◽  
Human Presence ◽  
Disturbed Areas ◽  
Disturbance Gradient ◽  
The Impact ◽  
Ctenosaura Similis ◽  
Flight Initiation

Abstract Studies on the impact of human activity on animal behaviour are critical for understanding the extent to which humans affect ecological dynamics. Previous studies have found that human presence alters antipredator behaviours, which can be measured by flight initiation distance (FID). We investigated escape behaviour of 96 black iguanas (Ctenosaura similis) across a gradient of human disturbance in six sites inside a protected area in Costa Rica. We used a field experiment to test for effect of human disturbance on FID. We found that individuals from higher disturbance sites had shorter FIDs, meaning that black iguanas from disturbed areas allow closer approaches. This finding is consistent with the prediction that some animals become more habituated to human presence as the degree of human disturbance increases. We propose that black iguanas’ ability to alter their behaviour in response to humans’ presence could make them especially adept at invading new environments.

scholarly journals Future Climate Change Will Have a Positive Effect on Populus davidiana in China

Forests ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1120 ◽  
Author(s):  
Jie Li ◽  
Guan Liu ◽  
Qi Lu ◽  
Yanru Zhang ◽  
Guoqing Li ◽  
...  
Keyword(s):  
Climate Change ◽  
Human Disturbance ◽  
Vulnerability Index ◽  
Future Climate ◽  
Future Climate Change ◽  
Climate Change Scenarios ◽  
Degree Of Protection ◽  
Populus Davidiana ◽  
The Impact ◽  
Degree Of Fragmentation

Since climate change significantly affects global biodiversity, a reasonable assessment of the vulnerability of species in response to climate change is crucial for conservation. Most existing methods estimate the impact of climate change on the vulnerability of species by projecting the change of a species’ distribution range. This single-component evaluation ignores the impact of other components on vulnerability. In this study, Populus davidiana (David’s aspen), a tree species widely used in afforestation projects, was selected as the research subject under four future climate change scenarios (representative concentration pathway (RCP)2.6, RCP4.5, RCP6.0, and RCP8.5). Exposure components of range change as well as the degree of fragmentation, degree of human disturbance, and degree of protection were considered simultaneously. Then, a multicomponent vulnerability index was established to assess the effect of future climate change on the vulnerability of P. davidiana in China. The results show that the distribution range of P. davidiana will expand to the northwest of China under future climate change scenarios, which will lead to an increased degree of protection and a decreased degree of human disturbance, and hardly any change in the degree of fragmentation. The multicomponent vulnerability index values of P. davidiana under the four emission scenarios are all positive by 2070, ranging from 14.05 to 38.18, which fully indicates that future climate change will be conducive to the survival of P. davidiana. This study provides a reference for the development of conservation strategies for the species as well as a methodological case study for multicomponent assessment of species vulnerability to future climate change.

scholarly journals Proximate and ultimate controls on carbon and nutrient dynamics of small agricultural catchments

2016 ◽  
Vol 13 (6) ◽  
pp. 1863-1875 ◽  
Author(s):  
Zahra Thomas ◽  
Benjamin W. Abbott ◽  
Olivier Troccaz ◽  
Jacques Baudry ◽  
Gilles Pinay
Keyword(s):  
Water Quality ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Water Chemistry ◽  
Human Disturbance ◽  
Nutrient Dynamics ◽  
Agricultural Activity ◽  
Agricultural Catchments ◽  
The Impact ◽  
The Relationship

Abstract. Direct and indirect effects from human activity have dramatically increased nutrient loading to aquatic inland and estuarine ecosystems. Despite an abundance of studies investigating the impact of agricultural activity on water quality, our understanding of what determines the capacity of a watershed to remove or retain nutrients remains limited. The goal of this study was to identify proximate and ultimate controls on dissolved organic carbon and nutrient dynamics in small agricultural catchments by investigating the relationship between catchment characteristics, stream discharge, and water chemistry. We analyzed a 5-year, high-frequency water chemistry data set from three catchments in western France ranging from 2.3 to 10.8 km2. The relationship between hydrology and solute concentrations differed between the three catchments and was associated with hedgerow density, agricultural activity, and geology. The catchment with thicker soil and higher surface roughness had relatively invariant carbon and nutrient chemistry across hydrologic conditions, indicating high resilience to human disturbance. Conversely, the catchments with smoother, thinner soils responded to both intra- and interannual hydrologic variation with high concentrations of phosphate (PO43−) and ammonium (NH4+) in streams during low flow conditions and strong increases in dissolved organic carbon (DOC), sediment, and particulate organic matter during high flows. Despite contrasting agricultural activity between catchments, the physical context (geology, topography, and land-use configuration) appeared to be the most important determinant of catchment solute dynamics based on principle components analysis. The influence of geology and accompanying topographic and geomorphological factors on water quality was both direct and indirect because the distribution of agricultural activity in these catchments is largely a consequence of the geologic and topographic context. This link between inherent catchment buffering capacity and the probability of human disturbance provides a useful perspective for evaluating vulnerability of aquatic ecosystems and for managing systems to maintain agricultural production while minimizing leakage of nutrients.

scholarly journals Bird Communities in Urban Riparian Areas: Response to the Local- and Landscape-Scale Environmental Variables

Forests ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 683
Author(s):  
Shiyi Guo ◽  
Chang Su ◽  
Kaoru Saito ◽  
Jiexin Cheng ◽  
Toru Terada
Keyword(s):  
Land Cover ◽  
Human Disturbance ◽  
Environmental Variables ◽  
Landscape Planning ◽  
Landscape Connectivity ◽  
Landscape Scale ◽  
Bird Communities ◽  
Riparian Areas ◽  
Total Contribution ◽  
The Impact

Understanding how environmental changes driven by urbanization impact the biodiversity in urban riparian areas has great importance for landscape planning and river ecosystem conservation. There have been many studies on the response of bird communities to different environmental variables in urban parks; however, although supporting some of the highest bird diversities, case studies in urban riparian areas remain limited. In existing research, few studies have considered the impact of both local waterfront characteristics and surrounding environmental variables at a larger scale. In this study, we selected birds as the indicator to clarify their response to both local- and landscape-scale environmental variables in riparian areas of Tsing river, Beijing, in terms of (a) vegetation composition, (b) human disturbance, (c) land cover, and (d) landscape connectivity. We hypothesized that birds with different biological characteristics may respond differently to environmental variables. Birds were then further grouped according to the habitat type, residential type, and feeding type. It turned out that the coverage of grass and the disturbance of pedestrians are the most influential variables. Besides, compared with the land cover and landscape connectivity, the total contribution of vegetation characteristics and human disturbance accounts for the main proportion of explained variance. Information pertaining to these environmental variables can provide evidence to support bird conservation efforts in urban areas, and the identified distance threshold provides a basis for future landscape connectivity assessments.

scholarly journals Assessing Restoration Potential of Fragmented and Degraded Fagaceae Forests in Meghalaya, North-East India

Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 1008
Author(s):  
Prem Prakash Singh ◽  
Tamalika Chakraborty ◽  
Anna Dermann ◽  
Florian Dermann ◽  
Dibyendu Adhikari ◽  
...  
Keyword(s):  
Tree Species ◽  
Human Disturbance ◽  
Abiotic Factors ◽  
Anthropogenic Disturbances ◽  
Fuel Wood ◽  
Mature Trees ◽  
North East ◽  
Large Trees ◽  
Restoration Potential ◽  
The Impact

The montane subtropical broad-leaved humid forests of Meghalaya (Northeast India) are highly diverse and situated at the transition zone between the Eastern Himalayas and Indo-Burma biodiversity hotspots. In this study, we have used inventory data from seedlings to canopy level to assess the impact of both biotic and abiotic disturbances on structure, composition, and regeneration potential of the Fagaceae trees of these forests. Fagaceae trees are considered as the keystone species in these forests due to their regional dominance and their importance as a fuel wood source, and also because they form an important component of climax community in these forests. Unfortunately, these forests are highly degraded and fragmented due to anthropogenic disturbances. We have assessed, for the first time, the restoration potential (i.e., capacity to naturally regenerate and sustain desired forest structure) of Fagaceae species in the genera Lithocarpus Blume, Castanopsis (D. Don) Spach, and Quercus Linn. We also evaluated how biotic and abiotic factors, as well as anthropogenic disturbances, influence the restoration potential of these species in six fragmented forest patches located along an elevational gradient on south-facing slopes in the Khasi Hills, Meghalaya. Fagaceae was the most dominant family at all sites except one site (Laitkynsew), where it was co-dominant with Lauraceae. Fagaceae forests have shown high diversity and community assemblages. Fagaceae species had high levels of natural regeneration (i.e., seedlings and saplings) but low recruitment to large trees (diameter at breast height or DBH ≥ 10 cm) at all sites. The ability to sprout was higher in Fagaceae tree species than non-Fagaceae tree species. We have shown that human disturbance and structural diversity were positively related to regeneration of Fagaceae tree species due to high sprouting. However, with increasing human disturbance, recruitment of saplings and pole-sized trees to mature trees hampered the resulting proportion of mature Fagaceae tree species. This study provides a means for assessing regeneration and a basis for forest management strategies in degraded and fragmented forests of Meghalaya.

scholarly journals Variability in the Structure of Phytoplankton Assemblages in relation to Human Disturbance in Southern Coast of Tunisia

2014 ◽  
Vol 2014 ◽  
pp. 1-10
Author(s):  
Lotfi Mabrouk ◽  
Lamia Dammak ◽  
Asma Hamza ◽  
Mabrouka Mahfoudhi ◽  
Med-Najmeddine Bradai
Keyword(s):  
Human Disturbance ◽  
Sampling Design ◽  
Scuba Diving ◽  
Industrial Effluents ◽  
Southern Coast ◽  
Phytoplankton Assemblage ◽  
Phytoplankton Assemblages ◽  
P Limitation ◽  
Hierarchical Sampling ◽  
The Impact

We investigated the impact of industrial effluents on phytoplankton assemblage in southern Tunisia (Skhira). We specifically addressed changes in microalgae composition caused by this anthropogenic interference. A hierarchical sampling design was used to compare planktonic microalgae structure between one disturbed station and one control station. Samples were collected by scuba diving at 5 m depth in August 2012. A total of 76 microalgae taxa were identified. Dinoflagellates abundance was low in the disturbed station, especially Gonyaulacales and Prorocentrales due to P-limitation, whereas diatoms and cyanobacteria abundance were low in control station which is characterized by Si-limitation.

scholarly journals Response of natural forest regeneration to human disturbance in Banke National Park

2015 ◽  
Vol 25 (1) ◽  
pp. 39-49 ◽  
Author(s):  
R. Napit ◽  
P. K. Paudel
Keyword(s):  
Human Disturbance ◽  
National Park ◽  
Forest Regeneration ◽  
Principal Component ◽  
Intermediate Disturbance Hypothesis ◽  
Environmental Damage ◽  
Human Disturbances ◽  
Regeneration Status ◽  
Main Challenge ◽  
The Impact

Tropical forest continues to decline in Nepal’s lowlands, with a serious negative consequence for biodiversity conservation. Even a strict natural reserve is subjected to have some degree of human disturbances. The newly established Banke National Park of Nepal provides an excellent context to evaluate effects of human disturbances on the forest regeneration status. This article assesses the regeneration status of the park. A total of 1,067 plots were laid out within the park area. In each plot, three concentric rings of radii of 10 m, 5 m, and 1 m were established. Data of seedling/sapling and human disturbance variables were collected from each of the concentric plots. Principal component analysis (PCA) of all disturbance variables was carried out to generate a disturbance index. The findings of this study alienates with intermediate disturbance hypothesis. Cut wood, lopped tree, human/livestock trails, people number - are the significant variables for the impact of sapling and seedling density in the park. The induced human disturbances up to the limit avails the highest regeneration status in the park. These human disturbances might have induced the spatial heterogeneity and internal dynamics which help in the regeneration. The main challenge for the forest managers and scientists is to identify the indicators of environmental damage of forest and their threshold levels at which human disturbances will result in an irreversible decline of the vegetation and its regeneration.Banko Janakari, A Journal of Forestry Information for NepalVol. 25, No. 1Page: 39-49

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