生态学报最新文献

Berberis lycium Royle a member of Berberidaceae family is an evergreen shrub native to the Himalayan region, particularly to Nepal. Several phytochemicals including alkaloids, saponins, tannins, vitamins, proteins, carbohydrates, lipids, berberine, berbamine, and sindamine have been extracted from various parts of the plant. The plant has also been shown to contain minerals such as calcium, copper, sodium, manganese, iron, sulphur, zinc, potassium, lead, and phosphorus. Owing to the presence of such biologically active chemicals, the extracts of the plant show several pharmacological activities like hyperlipidemic, hypoglycemic, hepatoprotective, anti-carcinogenic, and antipyretic. Moreover, the plant is being traditionally used to treat diarrhoea, intestinal colic, jaundice, piles, internal wounds, ophthalmia, rheumatism, and diabetes. Because of its important therapeutic characteristics, the plant is under risk of over-exploitation and other forms of anthropogenic pressure. In light of several recent findings and the prospects for future study, this review presents an inclusive account of its phytochemical constituents, biological activity, traditional use and conservation and management concerns.

Long-term studies in forest ecosystems are crucial to interpret the dynamics and are essential for conservation and management. However, characterizing long-term dynamics in relation to disturbance across dry tropics is often constrained by a dearth of data particularly from Indian tropics. In this context, a one-hectare permanent plot established in 2001 was revisited in 2011 and further re-censused in 2020 to ascertain species composition, stand structure and carbon stock dynamics of tree community over a 19-year period (2001−2020). Although species richness remained more or less unaffected, tree species composition did vary with the addition and loss of five and 10 species over this period. Species-level mortality rates overshadow the annual recruitment rate resulting in a net decrease in structural components. The results revealed that tree density decreased profoundly to 583 individuals ha⁻¹ in 2020, roughly 46% of the initial inventory. Similarly, basal area is reduced by 40% (from 58.27 m² ha⁻¹ to 34.91 m² ha⁻¹), highlighting the impact of increased site disturbance over 19 years. The distribution of individuals and basal area to various diameter classes displayed a reverse J-shaped trend in both the inventories suggesting that all the size classes suffered equally over the years. The total carbon stock was as high as 416.01 Mg ha⁻¹ in the initial inventory and reduced to 250.70 Mg ha⁻¹ in the present re-census. Relative carbon stock calculations revealed that Ficus benghalensis (−46.05 Mg ha⁻¹), Drypetes sepiaria (−22.68 Mg ha⁻¹) and Pterospermum canescens (−14.98 Mg ha⁻¹) represented 64.84% of total carbon stock loss over the period. Among the 29 resourceful species, Memecylon umbellatum, Drypetes sepiaria and Glycosmis mauritiana represented the highly targeted species with varied dietary and medicinal importance. These findings attest the impact of anthropogenic disturbances on species composition and carbon stock potential of the present site, which underline the need for such long-term monitoring efforts useful to forest management and conservation.

Flying squirrels are one of the least studied mammalian taxa in South Asia as well as in India owing to their nocturnal, arboreal and cryptic nature. We applied ensemble species distribution modeling using BIOMOD2 (ver 1.0) R-package to predict the suitable habitat of the Indian giant flying squirrel (Petaurista philippensis, Elliot 1839) in Indian biogeographic regions and states, and to identify the physical variables that define its fundamental niche. A subset of least correlated variables from bioclimatic (mean diurnal temperature range, temperature isothermality, precipitation of wettest month, precipitation of driest month and precipitation of warmest quarter, and precipitation of coldest quarter), topographic (elevation), water-related (distance to major water streams), and vegetation-related (NDVI, and vegetation height) data sets were used in the modeling. The accuracy of the final ensemble habitat suitability model was characterized by the receiver operating characteristic curve (ROC) and true skill statistic (TSS). In India, a total of highly suitable habitat for the species was estimated to be 66,743 sq. km, varying between states and biogeographic regions. Final model revealed that predictive suitable habitat of the species was limited primarily to the southern peninsula, including the Western Ghats, the Deccan peninsula, and the semi-arid region, and to a lesser extent, the coastal areas of the Kerala state. At the state level, majority of suitable habitat for the species estimated in Kerala followed by Karnataka, Tamil Nadu, Gujarat, Maharashtra, Rajasthan, and Madhya Pradesh. Climatic factors, particularly temperature and precipitation, have been identified as major determinants of Indian giant flying squirrel's potential habitat. We suggest that several new areas in the modeling that showed suitable habitat for the species necessitate immediate attention to validate species occurrence through field work. Extensive further studies on the species could also provide a detailed insight into the species' dispersion, colonization and the effect of future climate change in the Indian subcontinent.