Journal Articles
Permanent URI for this collectionhttps://mro.massey.ac.nz/handle/10179/7915
Browse
3 results
Search Results
Item Soil nutrient enrichment in pastoral systems through shelterbelts(Elsevier Ltd, 2025-10-01) Fonseka D; Jha N; Jeyakumar PShelterbelts along pasture boundaries are a natural, cost-effective, and sustainable solution to environmental challenges such as soil degradation and nutrient losses in New Zealand's pastoral systems. However, there's limited information on how shelterbelts affect nutrient dynamics in neighbouring pasture soils. Three field study sites, two dairy farms and one beef and sheep farm, consisting of the same soil type, were selected. Shelterbelts on the sites were composed of Pinus or Macrocarpa, or a mix of Macrocarpa and Willow. Soil samples were collected from each site, both with and without shelterbelts, at three transects for six distances (1 m, 5 m, 10 m, 20 m, 40 m, 80 m) and two soil depths (0–7.5 cm and 7.5–15 cm) in late spring 2023. Shelterbelts on all four farms significantly affected soil nutrient distribution in the adjacent area. Soils within 10 m of shelterbelts had higher total and Olsen phosphorus levels by up to 65 % and 80 %, respectively; the total and nitrate nitrogen levels increased by up to 64 % relative to control (no shelterbelt) soils. Shelterbelts increased soil organic carbon by up to 75 %. The macrocarpa and willow combined shelterbelt deposited around 17 Mg more C in the area tested compared to the control. These findings indicate that the shelterbelt with grazed pastures enhances phosphorus and nitrogen availability within the immediate vicinity. The inclusion of diverse species can contribute to the accumulation of topsoil carbon. Future research should focus on comparing more diverse tree species and improved grazing practices within shelterbelts to enhance the sustainability of the grazing farming system.Item The dominance of Ligularia spp. related to significant changes in soil microenvironment(Elsevier B.V., 2021-09-09) Ade L; Millner JP; Hou FExploring how plants adapt to and change the surrounding environment has become essential to understanding their survival strategies and co-evolution mechanisms. Ligularia virgaurea and Ligularia sagitta are the two most common species in the alpine grazing ecosystems of the eastern Qinghai-Tibetan Plateau (QTP) and becoming increasingly dominant. Studies have suggested that overgrazing has allowed Ligularia to gain a competitive advantage by changing plant community structure, which is often closely related to the soil environment. However, we don't fully understand the soil environment changes during this process, and the underlying mechanisms have not been explored. Therefore, we investigated plant community characteristics, soil fertility and soil microbial diversity in the L. virgaurea and L. sagitta communities on the eastern QTP. Ligularia spp. significantly changed the plant community by reducing biomass, vegetation coverage, abundance, and biodiversity, and the effect of L. sagitta on the plant community was stronger than that of L. virgaurea. In the plant communities dominated by L. virgaurea and L. sagitta, soil nutrients and soil microbial communities changed significantly. Aggregated boosted trees analysis revealed that soil Mg levels had the greatest relative influence on the structure and diversity of the soil microbial community. Our study provides data and a theoretical basis for revealing the survival strategies of L. sagitta and L. virgaurea and, provides a basis for weed management in grazed ecosystems.Item Plant invasion down under: exploring the below-ground impact of invasive plant species on soil properties and invertebrate communities in the Central Plateau of New Zealand(Springer Nature Switzerland AG, 2024-09-15) Pearson BM; Minor MA; Robertson AW; Clavijo McCormick ALThe impacts of invasive plants on arthropod communities are often reported to be negative and have predominantly been explored aboveground, but there is a paucity of information regarding what happens belowground. To address this gap, we compared soil properties and soil fauna communities associated with two native plant species (Leptospermum scoparium—mānuka and Chionochloa rubra—red tussock) and two invasive species (non-N-fixing Calluna vulgaris—European heather and N-fixing Cytisus scoparius—Scotch broom) in the Central Plateau of New Zealand. We expected that (1) at individual plant level soil properties would be different under invasive and native plant species, with higher soil nutrient concentrations under invasive species, especially N-fixing broom; (2) total abundance of soil fauna would be higher under invasive plant species, as generally positive impact of invasive plants on soil invertebrates is indicated in the literature; (3) invasive plants, and especially N-fixing broom, will be associated with greater abundances of soil decomposer groups. We found that soil properties and soil fauna assemblages did not cluster by plant invasive status as initially predicted. At individual plant level, there was similarity in soil conditions between mānuka and broom, and between red tussock and heather. The invasive N-fixer (broom) had positive effects on soil N availability, with higher N pool and lower C/N ratio in soil under this species. There were no consistent differences in total soil fauna abundance between invasive and native plants. Broom and mānuka were associated with higher abundances of Collembola, Oligochaeta and Diplopoda; heather and red tussock had higher abundances of Hymenoptera and Hemiptera. Significantly more Oligochaeta and Collembola under broom matched the prediction of invasive plants (and especially N-fixing invasives) being associated with greater abundances of decomposers. However, another important decomposer group—oribatid mites—did not show the same tendency. These results evidence that simplified generalizations regarding the impacts of invasive plants are unlikely to be justified, since the ecological effects of plant invasions are complex and do not always follow the same pattern. Therefore, we need to take into consideration the ecological context and the traits of individual plant species and target organisms in an unbiased manner to fully understand the impacts of plant invasions.