scholarly journals Impact of Disturbances on Species Diversity and Regeneration of Nepalese Sal (Shorea robusta) Forests Managed under Different Management Regimes

Earth ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 826-844
Author(s):  
Uttam Chapagain ◽  
Binod P. Chapagain ◽  
Sunil Nepal ◽  
Michael Manthey
Keyword(s):  
Species Richness ◽  
Protected Area ◽  
Buffer Zone ◽  
Community Forest ◽  
Managed Forest ◽  
Shorea Robusta ◽  
Management Regime ◽  
Disturbance Factor ◽  
Management Regimes ◽  
The Impact

Sal (Shorea robusta) forests, a dominant forest type in Nepal, experience different disturbance intensities depending on management regimes. This study compares the impact of disturbance on Nepalese Sal forests, which are managed on three major management regimes: protected area, state-managed forest, and buffer zone community forest. Using a systematic sampling approach, we sampled 20 plots, each covering 500 square meters, and nested plots within each main plot to measure pole and regeneration for each management regime. We recorded forest characteristics including tree species, counts, diameter, height, crown cover, and disturbance indicators. We compared forest attributes such as diversity indices, species richness, and stand structure by management regime using analysis of variance and regression analysis. The forest management regimes were classified into three disturbance levels based on disturbance factor bundles, and the buffer zone community forest was found to have the highest disturbance while the protected forest had the lowest disturbance. Species richness, diversity, evenness, abundance, density and basal area were higher, but regeneration was lower in protected area and state-managed forest compared to the buffer zone community forests. This suggests positive impacts of moderate disturbance on regeneration. The management plan should prioritize the minimization of excessive disturbance to balance forest conservation and provide forest resources to local users.

scholarly journals Impact of Management Regime and Regime Change on Gravel Barrier Response to a Major Storm Surge

2021 ◽  
Vol 9 (2) ◽  
pp. 147
Author(s):  
James A. Pollard ◽  
Elizabeth K. Christie ◽  
Susan M. Brooks ◽  
Tom Spencer
Keyword(s):  
Risk Management ◽  
Storm Surge ◽  
Natural State ◽  
Hydrodynamic Conditions ◽  
Natural Processes ◽  
Management Regime ◽  
Coastal Defense ◽  
Management Regimes ◽  
Coastal Risk ◽  
The Impact

Gravel barriers represent physiographic, hydrographic, sedimentary, and ecological boundaries between inshore and open marine offshore environments, where they provide numerous important functions. The morphosedimentary features of gravel barriers (e.g., steep, energy reflective form) have led to their characterization as effective coastal defense features during extreme hydrodynamic conditions. Consequently, gravel barriers have often been intensively managed to enhance coastal defense functions. The Blakeney Point Barrier System (BPBS), U.K., is one such example, which offers the opportunity to investigate the impact of alternative management regimes under extreme hydrodynamic conditions. The BPBS was actively re-profiled along its eastern section from the 1950s to the winter of 2005, whilst undergoing no active intervention along its western section. Combining an analysis of remotely sensed elevation datasets with numerical storm surge modeling, this paper finds that interventionist management introduces systemic differences in barrier morphological characteristics. Overly steepened barrier sections experience greater wave run-up extents during storm surge conditions, leading to more extreme morphological changes and landward barrier retreat. Furthermore, while high, steep barriers can be highly effective at preventing landward flooding, in cases where overwashing does occur, the resultant landward overtopping volume is typically higher than would be the case for a relatively lower crested barrier with a lower angled seaward slope. There is a growing preference within coastal risk management for less interventionist management regimes, incorporating natural processes. However, restoring natural processes does not immediately or inevitably result in a reduction in coastal risk. This paper contributes practical insights regarding the time taken for a previously managed barrier to relax to a more natural state, intermediary morphological states, and associated landward water flows during extreme events, all of which should be considered if gravel barriers are to be usefully integrated into broader risk management strategies.

scholarly journals Pteridophytic diversity in human-inhabited buffer zone of Murlen National Park, Mizoram, India

Check List ◽  
2017 ◽  
Vol 13 (2) ◽  
pp. 2081
Author(s):  
Sachin Sharma ◽  
Bhupendra S. Kholia ◽  
Ramesh Kumar ◽  
Amit Kumar
Keyword(s):  
Species Richness ◽  
Protected Area ◽  
National Park ◽  
Buffer Zone ◽  
Future Research ◽  
Site Preference

A taxonomic inventorization of pteridophytes occurring in a human inhabited buffer zone of Murlen National Park, India, was conducted in 2012 and 2013. This survey revealed 35 species belonging to 27 genera and 15 families. Polypodiaceae was recorded as dominant family, represented by six genera and eight species, followed by Pteridaceae (three genera and six species) and Lycopodiaceae (three genera and four species). Of the recorded species, 23 species were terrestrial, 11 (epiphytic) and two (lithophytic) in their habit forms. The species richness was highest in Tualpui village, with 11 species, followed by Rabung (7) and Ngur (6). The site preference of species among the villages is discussed. These data will provide baseline for future research and monitoring of pteridophytic vegetation in this protected area, as well as in similar habitats in the adjacent areas. 

scholarly journals Buffer Zone Resources and Community Conservation: A Case Study of Handi Khola Buffer Zone User Committee, Parsa Wildlife Reserve

2012 ◽  
Vol 12 ◽  
pp. 230-237
Author(s):  
Aruna Thapa ◽  
Dinesh R Bhuju
Keyword(s):  
Tree Species ◽  
Large Scale ◽  
Buffer Zone ◽  
Community Forest ◽  
Fuel Wood ◽  
Unequal Distribution ◽  
Shorea Robusta ◽  
Live Tree ◽  
Cut Stump ◽  
Wildlife Reserve

The present study was carried out to understand ecology of forests and social strata in Handi Khola Buffer Zone User Committee of Parsa Wildlife Reserve in Central Nepal. Methods used were stratified random sampling of household economics with questionnaire survey for socio-economic information and quantitative and qualitative analysis for vegetation study. Seventy two households were studied in-depth through household surveys. Vegetation ecology and forest resources were studied in Rakshaniya, Dhaneshwor, Laamitar and Masine forests of the BZ, totaling 37 sample plots. The study recorded a total of 36 tree species from 19 families. Shorea robusta was the dominant tree species in the community forest with highest important percentage, standing volume, biomass and sustainable fuel wood yield. The study area was sufficient to fulfill the demand of the fuel wood and timber in a sustainable way but annual demand of fodder (9640.54 tons/year) outstripped the annual sustainable supply of fodder (409.41 total digestible nutrient in tons/year). Thus, community forest was insufficient to provide the resource equally to all seasons and its unequal distribution compelled the locals for illegal extraction of resource showing some pressure on the reserve. In addition, large-scale human interference (Cut Stump Density-39.56/ha and Live Tree Density-58.11/ha) in community forest questioned the endurance of buffering potential and biodiversity conservation.DOI: http://dx.doi.org/10.3126/njst.v12i0.6507 Nepal Journal of Science and Technology 12 (2011) 230-237 

scholarly journals The effect of fire on soil oribatid mites (Acari: Oribatida) in a South African grassland*

Zoosymposia ◽  
2011 ◽  
Vol 6 (1) ◽  
pp. 210-220 ◽  
Author(s):  
ELIZABET A. HUGO-COETZEE ◽  
NICO L. AVENANT
Keyword(s):  
Species Richness ◽  
South African ◽  
Fire Regime ◽  
Residual Effect ◽  
Oribatid Mites ◽  
Fire Disturbance ◽  
Management Tool ◽  
Disturbance Factor ◽  
And Control ◽  
The Impact

Fire is a natural disturbance factor in southern African grasslands, and has become an important management tool for conservation of these habitats. Information on the impact of fire on any aspect of biodiversity will assist land managers to make more informed decisions on a fire regime that will conserve biodiversity in these grasslands. This is the first study to examine the responses of mite assemblages to fire disturbance in South African grasslands. The study was conducted in the Erfenis Dam Nature Reserve in central South Africa. An area of the Reserve was burned with a fast, hot fire while another area was left unburned as a control. Soil oribatid mites were collected over a period of one year from the burned and control areas. Oribatid assemblages exhibited seasonal patterns, with species richness and abundance slightly higher in early and late autumn and early spring. Four months after fire, there was no residual effect of fire on total abundance and species richness. However, species composition and the seasonal relative abundances of particular species, e.g. Multioppia wilsoni Aoki, 1964, Scheloribates confusia Coetzer, 1968 and Anellozetes auriculatus (Mahunka, 1984), differed between burned and control plots, demonstrating how targeted species can be investigated as indicators of post-fire recovery.

scholarly journals Flora of community managed forests of Palpa district, western Nepal

2018 ◽  
Vol 30 ◽  
pp. 102-120
Author(s):  
Pratiksha Shrestha ◽  
Ram Prasad Chaudhary ◽  
Krishna Kumar Shrestha ◽  
Dharma Raj Dangol
Keyword(s):  
Species Richness ◽  
Life Forms ◽  
Flowering Plant ◽  
Floristic Diversity ◽  
Managed Forests ◽  
Community Forest ◽  
Managed Forest ◽  
Fuel Wood ◽  
Community Forests ◽  
High Species Richness

Floristic diversity is studied based on gender in two different management committee community forests (Barangdi-Kohal jointly managed community forest and Bansa-Gopal women managed community forest) of Palpa district, west Nepal. Square plot of 10m×10m size quadrat were laid for covering all forest areas and maintained minimum 40m distance between two quadrats. Altogether 68 plots (34 in each forest) were sampled. Both community forests had nearly same altitudinal range, aspect and slope but differed in different environmental variables and members of management committees. All the species present in quadrate and as well as outside the quadrate were recorded for analysis. There were 213 species of flowering plant belonging to 67 families and 182 genera. Barangdi-Kohal JM community forest had high species richness i.e. 176 species belonging to 64 families and 150 genera as compared to Bansa-Gopal WM community forest with 143 species belonging to 56 families and 129 genera. According to different life forms and family and genus wise jointly managed forest has high species richness than in women managed forest. Both community forest are banned for fodder, fuel wood and timber collection without permission of management comities. There is restriction of grazing in JM forest, whereas no restriction of grazing in WM forest.

scholarly journals An assessment of the impact of silviculture and forest management regimes to forest cover change in the Churia region during 1992 to 2014

2018 ◽  
pp. 38-44
Author(s):  
B. K. Pokharel ◽  
D. R. Uprety ◽  
R. R. Niraula ◽  
P. R. Pokharel
Keyword(s):  
Forest Management ◽  
Forest Cover ◽  
Google Earth ◽  
Forest Cover Change ◽  
Community Forest ◽  
Gis And Remote Sensing ◽  
Community Forests ◽  
Silvicultural Practices ◽  
Management Regimes ◽  
The Impact

A study was conducted in the Churia region in 2014 to assess the change in forest cover as an outcome of the performance of various forest management regimes and silvicultural practices with the main objective to find the gap between those two. Geographic Information System (GIS) and Remote Sensing (RS) were used to compare the satellite imageries for the period of 1992 to 2014 in order to analyse the state of forest cover change. The demarcation of community forest boundaries was conducted based on available boundary maps and transferred to Google earth and GIS platform. Results showed that overall forest cover in the Churia region was increased by 7500 ha (1%) in 22 years, i.e. 1.35 million ha (76%) in 1992 to 1.36 million ha (77%) in 2014. The rate of deforestation in the Churia region was reduced as compared to the national average. However, degradation of landscape was visible at riverbeds and cultivation lands close to the riverbeds. It was also found that the area of dense forest was increased by 42,000 ha, whereas the area covered by bushes and grassland was reduced by 39,000 ha. The study further showed that there was a decline in cultivated land by 20,000 ha. Comparing the forest cover change in community forests with that of other management regimes, silvicultural practices in community forest areas have brought relatively better positive changes in the forest condition. It may be due to periodic silviculture operations carried out collectively by local communities. In the assessment, however, various elements of tenure rights and responsibilities of community, government and private forest and tree owners were identified and key silvicultural practices adopted by these regimes were highlighted as the drivers of positive or negative outcomes of forest cover change. Banko JanakariA Journal of Forestry Information for Nepal Special Issue No. 4, 2018, Page : 36-44 

scholarly journals Can clearcuts increase bird species richness in managed forests?

2008 ◽  
Vol 54 (No. 4) ◽  
pp. 189-193
Author(s):  
M. Żmihorski
Keyword(s):  
Species Richness ◽  
Bird Species ◽  
Bird Communities ◽  
Cumulative Number ◽  
Managed Forests ◽  
Managed Forest ◽  
Bird Species Richness ◽  
Forest Interior ◽  
Transect Counts ◽  
The Difference

Clearcuts are one of the results of forest management. The aim of this study was to assess the effect of clearcuts on bird communities in a managed forest in Western Poland. I applied the method of point transect counts. 20 points were located near clearcuts (less than 100 m from the nearest clearcut) and 25 points in the forest interior. In total, 36 bird species were recorded. On average, I found 9.20 bird species at points located near clearcuts and 6.72 species at points situated in the forest interior, and the difference was significant. The cumulative number of bird species for a given number of sampling points in the vicinity of clearcuts was higher than in the forest interior. The obtained results indicate that in managed, even-aged forests the generation of clearcuts can lead to an increase in local bird species richness.

scholarly journals Facilitation Effects of Haloxylon salicornicum Shrubs on Associated Understory Annuals, and a Modified “Stress-Gradient” Hypothesis for Droughty Times

Plants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1726
Author(s):  
Nasr H. Gomaa ◽  
Ahmad K. Hegazy ◽  
Arafat Abdel Hamed Abdel Latef
Keyword(s):  
Species Richness ◽  
Water Availability ◽  
Stress Gradient ◽  
Growing Season ◽  
Annual Species ◽  
Negative Effects ◽  
Growing Seasons ◽  
Dry Seasons ◽  
The Impact ◽  
Haloxylon Salicornicum

Perennial shrub-annual plant interactions play key roles in desert regions influencing the structure and dynamics of plant communities there. In the present study, carried out in northwestern Saudi Arabia, we examined the effect of Haloxylon salicornicum shrubs on their associated understory annual species across four consecutive growing seasons, along with a record of the seasonal rainfall patterns. We measured density and species richness of all the annual species in permanent quadrats located beneath individual shrubs, as well as in the spaces between shrubs. During wet growing season H. salicornicum shrubs significantly enhanced the density and species richness of sub-canopy species, whereas in the relatively dry seasons they exerted negative effects on the associated species. In all growing seasons, the presence of shrubs was associated with enhanced soil properties, including increased organic carbon content, silt + clay, and levels of nutrients (N, P and K). Shrubs improved soil moisture content beneath their canopies in the wet growing season, while in the dry seasons they had negative effects on water availability. Differences in effects of H. salicornicum on understory plants between growing seasons seem due to the temporal changes in the impact of shrubs on water availability. Our results suggest the facilitative effects of shrubs on sub-canopy annuals in arid ecosystems may switch to negative effects with increasing drought stress. We discuss the study in light of recent refinements of the well-known “stress-gradient hypothesis”.

scholarly journals NonlinearL2-Gain Analysis of Hybrid Systems in the Presence of Sliding Modes and Impacts

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
T. Osuna ◽  
O. E. Montano ◽  
Y. Orlov
Keyword(s):  
Sliding Mode ◽  
Numerical Study ◽  
Sufficient Conditions ◽  
Disturbance Attenuation ◽  
Sliding Modes ◽  
Time Dynamics ◽  
Attenuation Level ◽  
Disturbance Factor ◽  
Disturbance Attenuation Level ◽  
The Impact

TheL2-gain analysis is extended towards hybrid mechanical systems, operating under unilateral constraints and admitting both sliding modes and collision phenomena. Sufficient conditions for such a system to be internally asymptotically stable and to possessL2-gain less than ana priorigiven disturbance attenuation level are derived in terms of two independent inequalities which are imposed on continuous-time dynamics and on discrete disturbance factor that occurs at the collision time instants. The former inequality may be viewed as the Hamilton-Jacobi inequality for discontinuous vector fields, and it is separately specified beyond and along sliding modes, which occur in the system between collisions. Thus interpreted, the former inequality should impose the desired integral input-to-state stability (iISS) property on the Filippov dynamics between collisions whereas the latter inequality is invoked to ensure that the impact dynamics (when the state trajectory hits the unilateral constraint) are input-to-state stable (ISS). These inequalities, being coupled together, form the constructive procedure, effectiveness of which is supported by the numerical study made for an impacting double integrator, driven by a sliding mode controller. Desired disturbance attenuation level is shown to satisfactorily be achieved under external disturbances during the collision-free phase and in the presence of uncertainties in the transition phase.

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