Why they eat, what they eat: patterns of wild edible plants consumption in a tribal area of Western Himalaya

Background

From time immemorial, wild plants have been used for edible purposes. They still continue to be a major source of nutrition for tribal people. However, unfortunately, their use is now declining. This has implications in food security, narrowing genetic base, and future leads. The present study was, therefore, carried out in Chhota Bhangal region of Western Himalaya to analyze uses of wild edible plants (WEP) and the motivations behind their use or abandonment.

Methods

Field surveys were conducted to the study area from January 2016 to March 2017. Household surveys, group discussions, free listing, and structured questionnaires were used to elicit information on WEP. WEP use was categorized into six categories (vegetables, fruits, chutney, flavoring food, raw food, and local brew). Trends of use (continuing, decreasing, increasing, and not used) and motivations (environmental, economic, sociocultural, agriculture and land use practices, and human-wildlife conflict) behind their use were analyzed.

Results

Fifty plant species were used by the local people for edible purposes under six WEP categories. Mean and median of WEP used per respondent was 22.3 and 21, respectively. Highest number of these were used as vegetable (mean 8.9) while lowest were used as brew (mean 0.4). Out of the 50 WEP used, 20 were prioritized for motivation analyses. Though plant use is still maintained in the area, changes are evident. Almost 50% of the respondents revealed that they still continue the use of WEP while 36% reported trends of declining use as compared to 5–10 years back. Close to 10% respondents have stopped consuming WEP now and ~ 3% reported an increase in the use of WEP. Among the WEP categories, use of chutney showed an increasing trend. Sociocultural motivations were found to play a prime role, both, in limiting and promoting WEP use. Taste and aroma were the major sociocultural reasons behind using WEP while modernization and changing lifestyle were the main reasons behind declining use of WEP.

Conclusions

The study concludes that though use of WEP is still maintained in the area, changes in consumption trends are evident. Sociocultural motivations guided use of WEP in the area.

An ethnobotanical analysis of parasitic plants (Parijibi) in the Nepal Himalaya

BACKGROUND

Indigenous biocultural knowledge is a vital part of Nepalese environmental management strategies; however, much of it may soon be lost given Nepal's rapidly changing socio-ecological climate. This is particularly true for knowledge surrounding parasitic and mycoheterotrophic plant species, which are well represented throughout the Central-Eastern Himalayas but lack a collated record. Our study addresses this disparity by analyzing parasitic and mycoheterotrophic plant species diversity in Nepal as well as the ethnobotanical knowledge that surrounds them.

METHODS

Botanical texts, online databases, and herbarium records were reviewed to create an authoritative compendium of parasitic and mycoheterotrophic plant species native or naturalized to the Nepal Central-Eastern Himalaya. Semi-structured interviews were then conducted with 141 informants to better understand the biocultural context of these species, emphasizing ethnobotanical uses, in 12 districts of Central-Eastern Nepal.

RESULTS

Nepal is a hotspot of botanical diversity, housing 15 families and 29 genera of plants that exhibit parasitic or mycoheterotrophic habit. Over 150 of the known 4500 parasitic plant species (~3 %) and 28 of the 160 mycoheterotrophic species (~18 %) are native or naturalized to Nepal; 13 of our surveyed parasitic species are endemic. Of all species documented, approximately 17 % of parasitic and 7 % of mycoheterotrophic plants have ethnobotanical uses as medicine (41 %), fodder (23 %), food (17 %), ritual objects (11 %), or material (8 %).

CONCLUSIONS

Parasitic and mycoheterotrophic plant species exhibit high diversity in the Nepal Central-Eastern Himalaya and are the fodder for biocultural relationships that may help inform future environmental management projects in the region.

The rise of the Himalaya enforced the diversification of SE Asian ferns by altering the monsoon regimes

BACKGROUND

The rise of high mountain chains is widely seen as one of the factors driving rapid diversification of land plants and the formation of biodiversity hotspots. Supporting evidence was reported for the impact of the rapid rise of the Andean mountains but this hypothesis has so far been less explored for the impact of the "roof of the world". The formation of the Himalaya, and especially the rise of the Qinghai-Tibetan Plateau in the recent 20 million years, altered the monsoon regimes that dominate the current climates of South East Asia. Here, we infer the hypothesis that the rise of Himalaya had a strong impact on the plant diversity in the biodiversity hotspot of the Southwest Chinese Mountains.

RESULTS

Our analyses of the diversification pattern of the derived fern genus Lepisorus recovered evidence for changes in plant diversity that correlated with the strengthening of South East Asian monsoon. Southwest China or Southwest China and Japan was recovered as the putative area of origin of Lepisorus and enhancing monsoon regime were found to shape the early diversification of the genus as well as subsequent radiations during the late Miocene and Pliocene.

CONCLUSIONS

We report new evidence for a coincidence of plant diversification and changes of the climate caused by the uplift of the Himalaya. These results are discussed in the context of the impact of incomplete taxon sampling, uncertainty of divergence time estimates, and limitations of current methods used to assess diversification rates.

Indehiscent sporangia enable the accumulation of local fern diversity at the Qinghai-Tibetan Plateau

BACKGROUND

Indehiscent sporangia are reported for only a few of derived leptosporangiate ferns. Their evolution has been likely caused by conditions in which promotion of self-fertilization is an evolutionary advantageous strategy such as the colonization of isolated regions and responds to stressful habitat conditions. The Lepisorus clathratus complex provides the opportunity to test this hypothesis because these derived ferns include specimens with regular dehiscent and irregular indehiscent sporangia. The latter occurs preferably in well-defined regions in the Himalaya. Previous studies have shown evidence for multiple origins of indehiscent sporangia and the persistence of populations with indehiscent sporangia at extreme altitudinal ranges of the Qinghai-Tibetan Plateau (QTP).

RESULTS

Independent phylogenetic relationships reconstructed using DNA sequences of the uniparentally inherited chloroplast genome and two low-copy nuclear genes confirmed the hypothesis of multiple origins of indehiscent sporangia and the restriction of particular haplotypes to indehiscent sporangia populations in the Lhasa and Nyingchi regions of the QTP. In contrast, the Hengduan Mountains were characterized by high haplotype diversity and the occurrence of accessions with and without indehiscent sporangia. Evidence was found for polyploidy and reticulate evolution in this complex. The putative case of chloroplast capture in the Nyingchi populations provided further evidence for the promotion of isolated but persistent populations by indehiscent sporangia.

CONCLUSIONS

The presented results confirmed the hypothesis that indehiscent sporangia promote the establishment of persistent population in different regions of the QTP. These results are consistent with the expectations of reproductive reassurance by promotion of self-fertilization that played a critical role in the assembly of populations in isolated locations and/or extreme habitats.

Cushions of Thylacospermum caespitosum (Caryophyllaceae) do not facilitate other plants under extreme altitude and dry conditions in the north-west Himalayas

BACKGROUND

Cushion plants are commonly considered as keystone nurse species that ameliorate the harsh conditions they inhabit in alpine ecosystems, thus facilitating other species and increasing alpine plant biodiversity. A literature search resulted in 25 key studies showing overwhelming facilitative effects of different cushion plants and hypothesizing greater facilitation with increased environmental severity (i.e. higher altitude and/or lower rainfall). At the same time, emerging ecological theory alongside the cushion-specific literature suggests that facilitation might not always occur under extreme environmental conditions, and especially under high altitude and dryness.

METHODS

To assess these hypotheses, possible nursing effects of Thylacospermum caespitosum (Caryophyllaceae) were examined at extremely high altitude (5900 m a.s.l.) and in dry conditions (precipitation <100 mm year(-1)) in Eastern Ladakh, Trans-Himalaya. This is, by far, the highest site, and the second driest, at which the effects of cushions have been studied so far.

KEY RESULTS

In accordance with the theoretical predictions, no nursing effects of T. caespitosum on other alpine plants were detected. The number and abundance of species were greater outside cushions than within and on the edge of cushions. None of the 13 species detected was positively associated with cushions, while nine of them were negatively associated. Plant diversity increased with the size of the area sampled outside cushions, but no species-area relationship was found within cushions.

CONCLUSIONS

The results support the emerging theoretical prediction of restricted facilitative effects under extreme combinations of cold and dryness, integrating these ideas in the context of the ecology of cushion plants. This evidence suggests that cases of missing strong facilitation are likely to be found in other extreme alpine conditions.