Trends in Tree Diversity and Stand Structure during Restoration: A Case Study in Fragmented Moist Deciduous Forest Ecosystems of Northeast India

Abstract

Ecological implications for the conservation of fragmented forests to managed local plant diversity have recently drawn much attention of most conservationists. Present study investigates the importance of fragmented forests using different quantitative measures of species diversity and stand structure as indicators of natural restoration from past disturbances. Eleven independent 500 m × 10 m belt transects (5.5 ha) were established within fragmented low land moist deciduous forests of Tripura. All woody plants ≥10 cm girth at breast height (GBH) were measured. A total of 7,134 individuals with mean density of 648.55 stems ha −1 and 16.36 m 2 ha −1 of basal area were recorded, which represented 134 species, 93 genera, and 43 families of woody plants. Diversitydominance curve showed that maximum number of species were ranked >10 due to low abundance value. Maximum distributions of stems (>50%) were recorded at lowest girth class (10-30 cm) as an indication of advanced regeneration and significantly declined towards upper girth ( 2 adj = 0.93; < 0.0001) and height ( 2 adj = 0.95; < 0.0001) classes, which also indicated that some plants were adopted with ongoing disturbances through both seeded and nonseeded regeneration. Species richness ( 2 adj = 0.49; = 0.05), dominance ( 2 adj = 0.68; = 0.009), and density ( 2 adj = 0.62; = 0.02) were significantly increased at different disturbance intensities. Disturbances strongly influenced typical community association and structure by increasing diversity and population at certain magnitude and thereby showed declining trend towards maturation. Fragmented moist deciduous forests seek immediate attention as they represent spatial habitat for many economical or ecological important species, thus sustaining local biodiversity for livelihoods.

Effect of Fragmentation and Anthropogenic Disturbances on Floristic Composition and Structure of Subtropical Broad Leaved Humid Forest in Meghalaya, Northeast India

“…The proportion of individuals in the lower diameter class (5-15cm dbh) was high in the disturbed sites. Recruitment of light tolerant species might have increased the stem density of the stand following disturbance (Majumdar et al, 2014). The low density in Very Large category may be due to thinning effect caused by larger trees as reported from the sholas of Western Ghats (Mohandass and Davidar, 2010).…”

Changes of woody species diversity, horizontal and vertical distribution of stems across interior to outside within a primate rich habitat of Northeast India

“…However, Wild Boar, Barking Deer, Palm Civet, Wild Cat, Jackal, Indian Giant Squarrel, Wild Dog, and many species of birds and herpato-faunal species are concentrated in the interior zone (Gupta et al 2004). As per the classification system proposed by Champion and Seth (1968) and revised by Majumdar et al (2014) the main vegetation types of this sanctuary shows similar characteristics to Moist Mixed Deciduous Forest (3C/C3), East Himalayan Lower Bhabar Sal (3C/C1b (ii)), Moist Bamboo Brakes (2B/E3) and fragmented patches of Cachar Tropical Semi Evergreen Forest (2B/2s2/c2). Early 1980s, pure Dipterocarpus turbinatus or sometime mixed with Shorea robusta were predominantly distributed within in Kashari RF (Reserved Forest) and Trishna PRF (Protected Reserved Forest), which constituted the main reserve area of Trishna Wildlife sanctuary.…”

“…Each line transects encompassed five 10 m 9 100 m contiguous sub-plots (5 9 0.1 ha), thus 35 sub-plots (3.5 ha) were laid in the interior zone, 35 subplots (3.5 ha) plots in the marginal forest surrounding the interior forest and 30 sub-plots (3 ha) were laid outside the interior habitat close to human settlements. All the individual stem C10 cm gbh (girth at breast height) were measured in centimeter at 1.36 m height and height of each species were measured in nearest meters in living and nonliving categories (Majumdar et al 2014). All species encountered within the sampling plots that attained at C10 cm gbh were documented in the datasheets.…”

Do Extensive Rubber Plantation Influences Local Environment ? A Case Study from Tripura, Northeast India

“…However, some trees are kept inside or in the boarding the plantation for shade, fencing and timber requirements. A recent study found that diversity and density of trees in rubber plantation including its marginal forest fragments were low compared to other semi-natural plantation and natural vegetation 29,31 . The common species ofthe ground vegetation of rubber plantation include Altenthera sp., Cleodendrum viscosum, Pavetaindica, Spilanthuspaniculata, Desmodium sp., Blumiasp, Agiratumconyzoides, Spermacoseaehispida, Rungiapectinata, Momosapudica, Eupatorium odoratum etc.…”