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Can Potentilla fruticosa Linn. shrubs facilitate the herb layer of heavily grazed pasture on the eastern Tibetan Plateau

100%

Li P. , Krusi B. , Li S. , Cai X. , Yu F.

Polish Journal of Ecology

2011

tom Vol. 59, nr 1

129-140

The facilitative and competitive effects of shrubs on herbaceous species have been extensively studied, but little is known about the roles of the shrub distribution patterns in such effects. On a heavily grazed pasture on the Tibetan Plateau, we investigated the effects of Potentilla fruticosa Linn. shrubs of different distribution patterns on the small-scale vegetation pattern of the herb layer. We made same-sized releves at five micro-site types, i.e., beneath and outside the canopies of solitary Potentilla individuals, beneath and outside the canopies of edge-of-patch individuals and at the central openings of torusshaped large Potentilla patches. Shrubs protected certain species by increasing their frequencies of occurrence or flowering. However, only few species benefited from shrubs and more occurred or flowered more frequently outside. The data at community level indicated that species richness and diversity index were higher outside. The patch openings did not benefit species richness, pooled cover, diversity index or evenness of central vegetations. No special species was found growing beneath shrubs exclusively and few species were found with higher occurrences beneath shrubs. Furthermore, no significant difference was found between the two different distribution patterns at either community or species level. Vegetation ordinations confirmed this and vegetations beneath and outside the shrubs were distinguished merely. In conclusion, Potentilla facilitated some species in the herb layer and the patch openings did not show large protective effects. Also, distribution patterns of Potentilla did not affect the difference between vegetations beneath and outside shrub canopies.

Lura - indiogenous approach to biodiversity conservation by temporary community confinement of Mithuns (Bos frontalis) during growing season

100%

Jini D. , Bhagawati K. , Singh R. , Bhagawati R. , Alone R. A. , Ngachan S. V.

International Letters of Natural Sciences

2015

tom 44

The extraordinary knowledge of indigenous people about their immediate environment and natural resource base can be a great asset for conservation of biodiversity. The current study aims to investigate an indigenous method of grazing management through temporary confinement of Mithun (Bos frontalis) of whole village community in a well selected area in the forest during the cropping and growing season. The whole system is called Lura and practiced by Galo tribes of Eastern Himalayan region of India. Every year Lura management committee is formed that selects a new site based on number of Mithuns, forage availability, time period and several other key criteria without affecting flora-fauna diversity and rare medicinal plants. The practice checks continuous, free, random and selective grazing by Mithuns. It prevent continuous disturbance of soil surface due to treading, during growing and rainy seasons that avoid soil erosion and compaction, and facilitate seedling germination and the invasion by plants. Change of site, provide resting period to the forages in the previous Lura site especially during growth stage that allow them to renew and regenerate appreciably within 1-2 months. It also saves resources and time for construction of fencing in each Jhum and other agricultural site of each farmer. The confinement offers easy monitoring, protection and regular health assessment of the livestock. Thus, it is a multifaceted indigenous practice that ensures grazing management, biodiversity conservation, protection of standing agricultural crops and animal health management

The Influence of Disturbance Type on Precipitation - Use Efficiency at Functional Group and Species Scales in an Arid Habitat

80%

Busso C. A. , Montenegro O. A. , Torres Y. A. , Giorgetti H. D. , Rodriguez G. D.

Polish Journal of Ecology

2016

tom Vol. 64, nr 2

143--164

We used long-term datasets (1984–1992) to contrast precipitation-use efficiency estimates between various disturbance kinds at a functional group and/or a species scale. Effects of varying amounts of precipitation and plant cover on PUE were also examined. Field studies were conducted at northeastern, arid Patagonia, Argentina (40°39′49″S, 62°53′6.4″W). Within each management kind, biomass was sampled in 0.5 × 0.5m permanent plots (n = 30) over 9 years after defoliation at 5 cm stubble at the end of each growing season, and it was separated into species. Biomass sampling allowed determination of annual net primary production. Thereafter, species were grouped into each of three functional groups. Precipitation-use efficiency (PUE) was calculated as the total dry matter produced per unit surface area on any given year divided by the total rainfall in that year. Plant cover on 20 out of those 30 plots was determined to study the relationship between plant cover and PUE. The contribution of cool-season perennial grasses to total PUE was higher (P <0.05) than that found for the other two functional groups in all management kinds and years. PUE was similar (P> 0.05) in wet than dry years, and it was greater (P <0.05) or similar (P> 0.05), but not lower, on the more than less competitive perennial grass species in all management kinds. The relationship between plant cover and PUE was positive, linear (P <0.0000) and management-kind dependent.