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The present study carried out at three altitudes in Daksum range of Anantnag Forest division aimed to study the variation in floristic composition, community structure, regeneration status, soil characteristics and soil seed bank of Spruce dominated forests. A total of 47 plant species belonging to 41 genera and 29 families were reported. The number of species decreased with increasing altitude. Abies pindrow, Acer caesium and Pinus wallichiana were main tree associates of Picea smithiana. The regeneration of Spruce at all the sites was low and did not show any definite trend along the altitudinal gradient. There was a decrease in availability of OC, N, P, K, Fe and Zn with increase in soil depth at all the three altitudes. However, soil pH showed the reverse trend. There was an increase in availability of OC, N, P, K and Zn while decrease in pH and available Fe in soil with the increase in altitude. The viability of soil seed bank of spruce was found to be very low (15.36 to 18.18%). The study is a pioneer in this region in many aspects and hence shall be a benchmark for further management and conservation of this important species.

In the tropical dry deciduous forests of Central India, changes in population structure and regeneration of a Near Threatened tree Pterocarpus marsupium Roxb. (Fabaceae) was monitored over 4 years. Focussing on the effects of biotic disturbance, the study examined seven potential sites, for future restoration measures and management. We examined 46 plots of 0.1 ha size laid in these seven sites from 2017 to 2021. Results compared in all sites revealed that there were hardly any individuals surviving or growing at ‘Sapling’ stage, which is counted as crucial for successful regeneration of a tree species. Among all the study sites, SARA recorded highest average density of seedlings per sample plot followed by BAHO and LAMT. Positive change in ‘Seedlings’ category was recorded only at BAHO (+17.8%) and SARA (+9.1%). Whereas, BIRS recorded highest decline in average density of seedlings (−42.2%) followed by SEMA (−24.3%) and BARH (17.2%). Correlation analysis of biotic pressure on the species, revealed that weed infestation (−0.59) has highest adverse effect on the seedling density followed by Lopping/cutting (−0.33) and livestock & human population (−0.12), indicating an urgent need to undertake assisted natural regeneration (ANR) activities for this species in its natural ranges. Although there were few positive changes in the seedling stage (BAHO +17.8%; SARA +9.1%), but conditions of most sites did not meet the standards necessary for the survival and growth of a tree species. Therefore, the study concludes that lack of ability of seedlings to grow into saplings due to biotic pressure is the main limitation for the natural habitats of P. marsupium in Central India.

Weeds are recognized worldwide as an important environmental and economic burden in the human dominated landscape, particularly in the agro-ecosystems. Management of weeds is highly context specific and requires the knowledge of weed community structure at local levels. Additionally, periodic assessment of weed flora is essential because the weed community structure modifies over time due to changes in cropping patterns and arrival of invasive alien weeds. In this study we assessed the agricultural weed flora and weed community structure in legume fields (Macrotyloma uniflorum, Vigna angularis and Vigna mungo crops) dominated by invasive weed Ageratum houstonianum in a remote mountain village Gokuleshwor of Darchula district in north-west Nepal. Weed flora of the study area was inventoried by transect walk method and weed community structure in three crop fields were analyzed by quadrat sampling. We recorded 75 vascular plant species belonging to 67 genera and 29 families as agricultural weeds. Among them, 21 species (28%) were alien species naturalized in Nepal and 9 of these naturalized species were invasive. Asteraceae (18 species) was the most species-rich family, followed by Poaceae (10 species) and Malvaceae (5 species). Out of 75 weed species, 65 were also listed in the World Compendium of Weed. A. houstonianum had the highest biomass and the importance percentage in all three crop fields. Weed species richness and A. houstonianum biomass did not vary significantly among the three crop fields. The weed species richness significantly declined with increasing A. houstonianum biomass. The results suggest that the alien species contributed significantly to the weed flora of the upland farming system and an invasive weed became a dominant species of the weed community. Control of such weeds at their early stage of invasions can prevent them from becoming dominant weeds and protect the crop production systems from their negative impacts.

Invasive slugs are a menace from the agricultural point of view apart from the impact on the native biota and the ecosystems. Subsequent to the observations of the marsh slug, Deroceras laeve in West Bengal, India, an attempt was made to confirm the species identity and the species distribution modelling considering the Himalayas of West Bengal and adjacent regions as the geographical distribution of the species. Assessment of the DNA barcoding of the COI gene confirmed the species as D. laeve with 99.84% similarity with a specimen of Canada. Owing to its record from the concerned regions, the prospective spread and the invasion of the species in similar regions were modelled using Maxent species distribution modelling. The result of species distribution modelling indicated that precipitation seasonality, precipitation of the driest month, snow coverage, elevation, and herbaceous vegetation had the most influence on the occurrence of D. laeve. The possible spread of the species can be expected in the future if congenial conditions are available in the extended geographical regions. As an invasive species, D. laeve may affect agricultural productivity apart from altering the habitat conditions and imposing competitive interactions with the native species. Based on the present observation, appropriate strategies may be framed for monitoring and regulating the spread of the invasive slug.

Plant biodiversity in the dry ecosystem of the savanna is constantly under threat of extinction, thereby contributing to the ongoing climatic crisis. The systematic compilation of plant species growing in any region is an important tasks of ecological research centered on conservation. In the present study, a comprehensive and systematic inventory of the diversity and population structure of trees and shrubs growing on the Ungwar Jeji campus of Federal University Birnin Kebbi Northwestern Nigeria was provided. The data was collected using a standard 50 × 50 quadrat with 156 total sample plots stratified into plantation area (PA), undisturbed area (UA), building area (BA), and drive/walkways area (DA). Diversity indices were computed using PAST 3.17 software. The campus is richly endowed and diverse in species as revealed by the Margalef's species richness value of 4.753 and the Diversity Index Value (Shannon_ H′) of 2.51, respectively. The inventory recorded 39 species belonging to 17 families of trees (66.67%) and shrubs (30.77%). Fabaceae has the most species (30.77%), while the least families recorded 1 species (2.5%) each. Azadirachta indica and Acacia podalyriifolia recorded an IVI of 55.4 and 99.62 making them the most important tree and shrub species respectively. Ficus platyphylla (2.82%) is the least. Most of the species encountered are of least concern (89.19%) except for Vitellaria paradoxa, which is Vulnerable (2.70%) according to the IUCN Red List version 2021–2. This preliminary inventory is useful for the planning and implementation of a sustainable conservation strategy on the campus. DNA conservation of the species is recommended.

This research was aimed to document the ethnobotanical information of plants used as sedatives, analgesic and blood tonic in Abeokuta, Nigeria and to evaluate the phytochemical, mineral and anti-nutrient contents in some of these plants. A total of 60 structured and validated questionnaires were administered using purposive sampling method. The names of plants were further authenticated using the plant list (www.theplantlist.org) and the world flora (www.worldfloraonline.org). Twenty-eight (28) plants belonging to Twenty-one (21) families were documented as being used as sedatives, analgesic and blood tonic. The most frequently mentioned were Theobroma cacao, Morinda lucida, Sorghum bicolor, Alstonia congensis, Harungana madagascariensis and Viscum album. Parts of the plants mentioned by respondents were leaves (78.3%), stem bark (18.3%), roots (3.3%). T. cacao contained highest amount of sodium (18.69 mg/100 g). Potassium (73.35 mg/100 g), Calcium (40.20 mg/100 g), Phosphorus (11.80 mg/100 g) and Magnesium (4.59 mg/100 g) were significantly higher in the leaves of Alstonia congensis. Oxalate (0.28 mg/100 g), Phytate (0.36 mg/100 g) and trypsin inhibitor (0.17 mg/100 g) were significantly higher (p < 0.05) in leaves of T. cacao. Cyanogenic glycosides were also higher in the leaves of Morinda lucida (0.26 mg/100 g). Highest alkaloid content (9.80 mg/100 g) was recorded in T. cacao. Morinda lucida contained highest amount of saponin (0.42 mg/100 g), tannin (0.32 mg/100 g) and steroid (0.25 mg/100 g) while the highest amount of flavonoid was recorded in Alstonia congensis. The immense benefits derived from the mineral composition, anti-nutrient content and phytochemical composition of these plants have made them highly useful in herbal medicine for treating various illnesses.

Cenchrus ciliaris corresponds to a perennial grass that is widespread in arid environments. This study aimed to assess growth and leaf exchange under water deficit stress of tetraploid (P1) and hexaploid (P2) individuals of C. ciliaris. The experiment was conducted under four treatments (Tc, T1, T2, and T3). Growth phenology, photosynthesis (A), stomatal conductance (Gs), CO₂ concentration, and transpiration (Tr) were observed during the stress cycle. The obtained results revealed that the highest growth potentialities were recorded for P2 population in both treatments. Both populations responded differently to water deficit stress displaying various values for tiller and the number of spikes. A significant effect of soil moisture treatments on C. ciliaris plant biomass was recorded (P < 0.05). Moreover, there were different responses to drought stress between both contrasting populations. The results also demonstrated that polyploidy level affected only the phenological parameters. Photosynthetic parameters, such as (A) and (Gs) significantly decreased under severe stress between populations and treatments. It could be inferred that C. ciliaris accessions respond to drought through showing significant changes in their physiological and phenological behavior.

Karst rocky desertification is a process of land degradation that involves serious soil erosion, severe decrease in soil productivity, extensive exposure of basement rocks, and the appearance of a desert-like landscape. Rocky desertification is caused by various factors and is considered a major socio-environmental problem. Furthermore, it triggers a serious threat to the ecological security and downgrades sustainable economic and social development. Unfortunately, in China karst rocky desertification is occurring in tropical and subtropical terrains of South China, especially in the Southwestern regions. Which severely limits local socio-economic development. In this paper, the natural and anthropogenic factors that cause karst rocky desertification are analyzed. To mitigate the severity of rocky desertification, the Chinese government has implemented many ecological projects in degraded regions during the past 40 years; indeed, encouraging results were achieved. In these thorough studies, the “Qing-Long Model” was proven to be a successful model for the restoration and treatment of rocky karst desertification in Southwestern China. This was reached by planting grass suitable for local growth and raising Qing-long goat (capra hircus), a local famous hybrid goat brand, which enhanced the ecological livestock husbandry in the karst mountains. Qing-long model is not only applicable for China, but also to other countries that face similar karst environmental problems as well. Through Qing-long model, China provides a solution to the karst rocky desertification challenge, consequently, environmental problems will be mitigated and social, ecological, and economic development will flourish again.