scholarly journals Forest structure and anthropogenic disturbances regulate plant invasion in urban forests

2021 ◽  
Author(s):  
Prakash Chandra Aryal ◽  
Chandramani Aryal ◽  
Kiran Bhusal ◽  
Devendra Chapagain ◽  
Man Kumar Dhamala ◽  
...  
Keyword(s):  
Forest Structure ◽  
Plant Invasion ◽  
Urban Forests ◽  
Anthropogenic Disturbances

scholarly journals Forest Structure and Anthropogenic Disturbances Regulate Plant Invasion in Urban Forests

2021 ◽  
Author(s):  
Prakash Chandra Aryal ◽  
Chandramani Aryal ◽  
Kiran Bhusal ◽  
Devendra Chapagain ◽  
Man Kumar Dhamala ◽  
...  
Keyword(s):  
Invasive Species ◽  
Forest Structure ◽  
Urban Forest ◽  
Urban Forests ◽  
Principal Component ◽  
Anthropogenic Disturbances ◽  
Invasion Success ◽  
Anthropogenic Factors ◽  
Forest Patches ◽  
Factors Affecting

Abstract Urban forest ecosystems, the structure and functions therein, are subjected to anthropogenic disturbances. Native and sensitive species from those forests might be lost due to such disturbances. At the same time, supplemented anthropogenic resources might create opportunities for exotic and invasive species. Although, invasive species are considered as one of the major threats to the urban biodiversity and ecosystems, the researches on invasion dynamics in the Himalayas have mostly focused on the impacts of invasion on forest structure and productivity. This study aims to understand the influence of forest structure and anthropogenic factors in invasion success that are poorly covered in the existing literature. We selected 11 urban forest patches for the study considering the presence-absence of selected invasive species and structural attributes. We used Principal Component Analysis (PCA) to reduce co-linearity in the covariates and generalized linear mixed effects model (GLMM) to identify the factors affecting the invasion success. We found that the structural attributes of the forests and anthropogenic disturbances regulated invasion success in urban forests. This implies that maintaining urban forest structural attributes, especially maintaining the stands with large-sized trees, are essential to regulate and control invasion in the context of urbanization.

scholarly journals Occurrence and Activity of Roe Deer in Urban Forests of Warsaw

2020 ◽  
Vol 3 (1) ◽  
pp. 35
Author(s):  
Karolina D. Jasińska ◽  
Mateusz Jackowiak ◽  
Jakub Gryz ◽  
Szymon Bijak ◽  
Katarzyna Szyc ◽  
...  
Keyword(s):  
Predation Risk ◽  
Urban Area ◽  
Roe Deer ◽  
Urban Forests ◽  
Anthropogenic Disturbances ◽  
Camera Traps ◽  
Human Disturbances ◽  
Human Presence ◽  
Big Cities ◽  
High Level

Human presence or activities are perceived by animals as those associated with predation risk so activity and exploration patterns of animals should be shaped by indices of anthropogenic disturbances. The high level of human disturbances is noticed in big cities. Therefore, the aim of the study was to determine the occurrence of roe deer in Warsaw and its activity in the Warsaw urban forests. We used snow tracking on transect routes (winter seasons 2016, 2017, 2018; 115.1 km in total) to determine roe deer occurrence in four habitats: forests, open areas, parks, and built-up areas. The number of tracks was highest in forests (4.6 tracks/1 km/24 h), followed by open areas, built-up areas, and parks. We used camera traps to determine the activity of roe deer in selected urban forests. We collected 697 observations of roe deer in Warsaw forests in the years 2016–2019 (per 4826 trap-days in total). The peak of roe deer activity was noticed between 4:00 and 5:00 a.m. Animals were least active at 1:00–2:00 p.m. and between 11:00 p.m.–01:00 a.m. Our research showed that roe deer inhabiting the urban area avoided human presence by using well-covered habitats and being active in periods when humans’ disturbances’ level is lower.

scholarly journals Present-day central African forest is a legacy of the 19th century human history

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Julie Morin-Rivat ◽  
Adeline Fayolle ◽  
Charly Favier ◽  
Laurent Bremond ◽  
Sylvie Gourlet-Fleury ◽  
...  
Keyword(s):  
19Th Century ◽  
Forest Structure ◽  
Interdisciplinary Approach ◽  
Anthropogenic Disturbances ◽  
Human History ◽  
Local Populations ◽  
Silvicultural Practices ◽  
History Of ◽  
The 19Th Century

The populations of light-demanding trees that dominate the canopy of central African forests are now aging. Here, we show that the lack of regeneration of these populations began ca. 165 ya (around 1850) after major anthropogenic disturbances ceased. Since 1885, less itinerancy and disturbance in the forest has occurred because the colonial administrations concentrated people and villages along the primary communication axes. Local populations formerly gardened the forest by creating scattered openings, which were sufficiently large for the establishment of light-demanding trees. Currently, common logging operations do not create suitable openings for the regeneration of these species, whereas deforestation degrades landscapes. Using an interdisciplinary approach, which included paleoecological, archaeological, historical, and dendrological data, we highlight the long-term history of human activities across central African forests and assess the contribution of these activities to present-day forest structure and composition. The conclusions of this sobering analysis present challenges to current silvicultural practices and to those of the future.

scholarly journals Regeneration patterns in Mexican pine-oak forests

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Teresa Alfaro Reyna ◽  
Jordi Martínez-Vilalta ◽  
Javier Retana
Keyword(s):  
Climate Change ◽  
Environmental Factors ◽  
Global Change ◽  
Spatial Patterns ◽  
Land Tenure ◽  
Forest Structure ◽  
Anthropogenic Disturbances ◽  
Oak Forests ◽  
Mixed Stands ◽  
If Current

Abstract Background Global change is causing an increase in the incidence of natural and anthropogenic disturbances on forests, which frequently interact synergistically and promote changes in forest structure, composition and functioning. In this study we evaluate the regeneration of Pinaceae and Fagaceae species in pure and mixed stands in Mexico to determine if current regeneration patterns are indicative of changes in the relative dominance of these two tree families, as observed in other temperate regions. We also identify the environmental factors that determine the regeneration patterns of Pinaceae and Fagaceae species in these forests. Results We use data from two consecutive surveys of the National Inventory of Forests and Soils of Mexico (INFyS), obtained in 2004–2009 and 2009–2014. Our results show that the spatial patterns of regeneration are affected by forest structure, by climate, by the type and intensity of disturbances and by land tenure. Importantly, the presence and abundance of Fagaceae regeneration is generally higher than that of Pinaceae, and tends to be favoured (relative to Pinaceae) under warmer climates and by the presence of wildfires. Conclusions The higher regeneration of Fagaceae relative to Pinaceae under warmer and fire-prone conditions could have important impacts on the composition and functioning of Mexican temperate forests under ongoing climate change, as well as affect their resilience to future disturbances.

Intra-annual phenology for detecting understory plant invasion in urban forests

2018 ◽  
Vol 142 ◽  
pp. 151-161 ◽  
Author(s):  
Kunwar K. Singh ◽  
Yin-Hsuen Chen ◽  
Lindsey Smart ◽  
Josh Gray ◽  
Ross K. Meentemeyer
Keyword(s):  
Plant Invasion ◽  
Urban Forests ◽  
Understory Plant

scholarly journals Effects of Environmental Factors and Alien Plant Invasion on Native Floral Diversity in Mt. Manunggal, Cebu Island, Philippines

2018 ◽  
Vol 13 (3) ◽  
pp. 390-402
Author(s):  
JAKE JOSHUA CHI GARCES ◽  
MARY JOYCE LAPA FLORES
Keyword(s):  
Environmental Factors ◽  
Plant Invasion ◽  
Environmental Parameters ◽  
Anthropogenic Disturbances ◽  
The Philippines ◽  
Alien Plants ◽  
Native Plant ◽  
Plant Abundance ◽  
Alien Plant ◽  
Floral Diversity

The status of native floral diversity in Mt. Manunggal, Cebu Island, the Philippines in relation to environmental factors and alien plant invasion has not been recorded and published. To assess factors influencing native plant communities in Mt. Manunggal, a vegetation survey of native and alien plants, as well as selected environmental variables at two sites (Site 1- invaded plot; Site 2- adjacent uninvaded plot) were measured, and anthropogenic disturbances observed using a t-test, regression analysis, and Pearson correlation. For each site, selected environmental parameters, as well as native and alien plant abundance and diversity, were determined last October-November, 2016. There was also a characterization of sites with respect to anthropogenic disturbances. Altitude (t= -14.11, p=0.000), soil temperature (t=2.68, p=0.014), and light intensity (t = -2.61; p=0.016) significantly differed between study sites due to the complex topography and geology of Mt. Manunggal, the variation in floral cover, and degree of anthropogenic activities. Among all environmental factors at both sites, altitude was highly positively correlated to alien plant abundance (r=0.709;p=0.000) at Site 1 while native plant abundance at Site 2 was negatively correlated with soil pH (r=-0.579;p=0.003).There was an apparent domination of alien plants in terms of species richness and abundance at both sites and this could have significantly affected native plant abundance. The strong correlation of environmental parameters to alien plant invasion could favor the continued dominance of alien plant species, resulting in a further decrease of native species.

Habitat fragmentation causes collapse of kelp recruitment

2020 ◽  
Vol 648 ◽  
pp. 111-123
Author(s):  
C Layton ◽  
MJ Cameron ◽  
M Tatsumi ◽  
V Shelamoff ◽  
JT Wright ◽  
...  
Keyword(s):  
Habitat Fragmentation ◽  
Patch Size ◽  
Life Stage ◽  
Extended Period ◽  
Anthropogenic Disturbances ◽  
Anthropogenic Sources ◽  
Kelp Forests ◽  
Natural Disturbances ◽  
Short Term ◽  
Turf Algae

Kelp forests in many regions are experiencing disturbance from anthropogenic sources such as ocean warming, pollution, and overgrazing. Unlike natural disturbances such as storms, anthropogenic disturbances often manifest as press perturbations that cause persistent alterations to the environment. One consequence is that some kelp forests are becoming increasingly sparse and fragmented. We manipulated patch size of the kelp Ecklonia radiata over 24 mo to simulate persistent habitat fragmentation and assessed how this influenced the demography of macro- and microscopic juvenile kelp within the patches. At the beginning of the experiment, patch formation resulted in short-term increases in E. radiata recruitment in patches <1 m2. However, recruitment collapsed in those same patches over the extended period, with no recruits observed after 15 mo. Experimental transplants of microscopic and macroscopic juvenile sporophytes into the patches failed to identify the life stage impacted by the reductions in patch size, indicating that the effects may be subtle and require extended periods to manifest, and/or that another life stage is responsible. Abiotic measurements within the patches indicated that kelp were less able to engineer the sub-canopy environment in smaller patches. In particular, reduced shading of the sub-canopy in smaller patches was associated with proliferation of sediments and turf algae, which potentially contributed to the collapse of recruitment. We demonstrate the consequences of short- and longer-term degradation of E. radiata habitats and conclude that habitat fragmentation can lead to severe disruptions to kelp demography.

Role of Horses as Potential Vectors of Non-Native Plant Invasion: An Overview

2020 ◽  
Vol 40 (3) ◽  
Author(s):  
Lauren D. Quinn ◽  
Adda Quinn ◽  
Mietek Kolipinski ◽  
Bonnie Davis ◽  
Connie Berto ◽  
...  
Keyword(s):  
Plant Invasion ◽  
Native Plant
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