Restoration Driven Recovery of Herbaceous Plant Diversity in a Degraded Dryland Ecosystem of the Indian Thar Desert
Bhawana Sharma *
Forest Ecology & Climate Change Division, ICFRE–Arid Forest Research Institute (ICFRE–AFRI), Jodhpur, Rajasthan, India.
Shera Ram Baloch
ICFRE–Arid Forest Research Institute (ICFRE–AFRI), Jodhpur, Rajasthan, India.
Sharat Kothari
ICFRE–Arid Forest Research Institute (ICFRE–AFRI), Jodhpur, Rajasthan, India.
*Author to whom correspondence should be addressed.
Abstract
Aims: To evaluate whether plantation-based restoration and site protection were associated with the recovery of herbaceous plant richness and diversity in a degraded sandy plain of the Indian Thar Desert during the first three years after restoration establishment.
Study Design: A three-year comparative field study of a plantation/restoration field (PF) and an adjacent outside plantation field (OPF), using independent random quadrat surveys.
Place and Duration of Study: Karah Jod, Hameera, Jaisalmer district, western Rajasthan, India. Herbaceous vegetation was surveyed in October 2022, October 2023 and October 2024.
Methodology: Herbaceous vegetation was sampled using randomly placed 1 m × 1 m quadrats. In 2022, 88 quadrats were sampled in each field; in 2023 and 2024, 88 PF quadrats and 50 OPF quadrats were sampled. Species richness, Shannon diversity (H′), Gini–Simpson diversity (1−D) and Pielou evenness (J′) were calculated. Richness was standardised to 50 quadrats using sample-based rarefaction. PF–OPF differences were tested using two-sided Mann–Whitney U tests and Cliff’s delta, and temporal differences were tested using Kruskal–Wallis tests.
Results: Observed PF richness increased from 5 species in 2022 to 32 in 2023 and 24 in 2024, whereas OPF richness changed from 3 species in 2022 to 6 species in both 2023 and 2024. Standardised richness was 5.00, 30.86 and 23.99 species in PF compared with 2.92, 6.00 and 6.00 in OPF. Community Shannon diversity remained higher in PF (1.537–2.582) than in OPF (1.072–1.493). Mean PF quadrat richness increased from 1.06 to 5.25 and 7.91 species, and the PF–OPF richness effect increased from Cliff’s delta = 0.464 in 2022 to 1.000 in 2024 (p < 0.001).
Conclusion: Restoration and protection were associated with rapid enhancement of herbaceous richness and local diversity. Herb-layer biodiversity can be used as an indicator of dryland restoration progress.
Keywords: Arid ecosystem, ecological restoration, herbaceous vegetation, Jaisalmer, plant diversity, rarefaction, species richness, Thar Desert