Bacteria Respond Stronger Than Fungi Across a Steep Wood Ash-Driven pH Gradient

Soil pH is probably the most important variable explaining bacterial richness and community composition locally as well as globally. In contrast, pH effects on fungi appear to be less pronounced, but also less studied. Here we analyze the community responses of bacteria and fungi in parallel over a local extreme pH gradient ranging from 4 to 8. We established the pH gradient by applying strongly alkaline wood ash in dosages of 0, 3, 9, 15, 30, and 90 t ha–1 to replicated plots in a Picea abies plantation and assessed bacterial and fungal community composition using high throughput amplicon sequencing 1 year after ash application. At the same time, the experiment investigated if returning wood ash to plantation forests pose any immediate threats for the microbial communities. Among the measured environmental parameters, pH was by far the major driver of the microbial communities, however, bacterial and fungal communities responded differently to the pH increment. Whereas both bacterial and fungal communities showed directional changes correlated with the wood ash-induced increase in pH, the bacterial community displayed large changes at wood ash dosages of 9 and 15 t ha–1 while only higher dosages (>30 t ha–1) significantly changed the fungal community. The results confirm that fungi are less sensitive to pH changes than bacteria but also that fertilizing plantation forests with wood ash, viewed through the lens of microbial community changes, is a safe management at standard dosages (typically 3 t ha–1).

Seasonal Variations Affect The Ecosystem Functioning And Microbial Assembly Processes In Plantation Forests

Background: While afforestation mitigates climate concerns, the impact of afforestation on soil microbial compositions, ecological assembly processes, and multiple soil functions (multifunctionality) in afforested areas remains unclear. The Xiong'an New Area plantation forests (Pinus and Sophora forests) were selected to examine the effects of plantation types in four contrasting seasons on soil microbiomes.Results: We evaluated three functional categories (nutrient stocks, organic matter decomposition, and microbial functional genes) of multifunctionality, and the average (net) multifunctionality was quantified. The results showed that net soil multifunctionality as a broad function did not change seasonally, unlike other narrow functional categories. Bacterial communities were deterministically (variable selection and homogenous selection) structured, whereas the stochastic process of dispersal limitation was mainly responsible for the assembly and turnover of fungal and protist communities. Additionally, we showed that winter triggered an abrupt transition in the bacterial community assembly from deterministic to stochastic processes in Pinus forests that was closely associated with a reduction in the bacterial Shannon diversity, with functional patterns of a high level of nutrient cycling (nutrient stocks and organic matter decomposition). Conclusions: Overall, the present study contributes local-ecosystem prospects to model the behavior of soil biota seasonally and their implied effects on soil functioning and microbial assembly processes in plantation forests.

Low impact of forest conversion on biodiversity: evidence from small mammals in contrasting forests of Mt. Liangshan, China

Secondary and plantation forests are the main alternative forests remaining after the deforestation of primary forests. Understanding the conservation value of secondary and plantation forests is important for resource utilization. To explore the impact of forest conversion on biodiversity, we compared multiple diversity metrics (taxonomic, phylogenetic and functional diversity) and community structures of small mammals in the primary, secondary and plantation forests on Mt. Liangshan, Sichuan Province, China. Seven field surveys were conducted to survey local small mammal assemblages between 2016 and 2020. We found that the taxonomic, phylogenetic and functional diversity metrics of small mammals in the three forest types were similar at the landscape scale, while all diversity metrics were lowest in the plantation forest and highest in the primary forests at the site scale. The community structure analysis showed that random processes were dominant across the three forest types, and there was no difference in small mammal community structures among the three forest types. Our results indicated that secondary and plantation forests in the nature reserves, adjacent to the primary forest and exposed to little human disturbance, also can provide important habitats for small mammals.

Assessment of forest health status of Panca Indah Lestari Community Plantation Forest (case study in Bukit Layang Village, Bakam District, Bangka Regency, Bangka Belitung Province)

Currently, community plantation forests play an essential role in providing wood supply for the timber industry with due regard to sustainability. One way to achieve the sustainability aspects of forest management is by conducting monitoring forest health. This study aims to determine the value of the health status of the Panca Indah Lestari Community Plantation Forest. This community plantation forest is located in Bukit Layang Village, Bakam District, Bangka Regency, Bangka Belitung Province. The stages of this research include: determining the number of cluster-plots using sampling intensity based on the area of community plantation forest, making cluster plots based on Forest Health Monitoring (FHM) cluster-plot design, collecting data by measuring the ecological indicators of forest health (productivity and vitality) based on the FHM method, as well as data analysis and processing using the Forest Health Assessment Information System. The results showed that the health status of the Panca Indah Lestari Community Plantation Forest had a range of values ranging from 1,890 - 5,530. The average health status value of Panca Indah Lestari Community Plantation Forest is 4,210, which was included in the medium category. Thus, the value of the health status of community plantation forests illustrates that the conditions for productivity and vitality indicators are insufficient. Knowing the forest condition’s status value helps managers provide recommendations in making decisions on sustainable community plantation forest management.

Perceptions by Smallholder Farmers of Forest Plantations in Malaysia

Plantation forests are perceived to be the supplementary source of wood material for the large wood products industry in Malaysia, amidst the steadily reducing supply from her natural forests. Despite the government’s initiated plantation forests scheme, the participation of smallholder farmers has been limited. Smallholder farmers constitute the largest proportion of private farmers involved in all sectors of agricultural and plantation tree crop cultivation, including commodities such as rubber and palm oil. Therefore, this study examines the lack of interest among smallholder farmers to participate in establishing forest plantations, although they have a strong presence in the palm oil and rubber sectors. A structured questionnaire survey was conducted among 12,895 smallholder farmers currently involved in palm oil, rubber and other tree-crop cultivation. The study found that this group has little knowledge and awareness of the forest plantation scheme available, and there is a prevailing perception that the establishment of forest plantations is not environment-friendly and leads to biodiversity loss. The poor economic return, small land holding, and poorly structured market and supply chain are perceived as the significant constraints faced that limit the interest among the target groups to participate in this sector. Any effort to reverse this trend and garner higher interest from the target group will necessarily require a new policy framework that boosts the economic outlook of forest plantations among smallholder farmers.

Effects of Randomized Management on the Forest Distribution Patterns of Larix kaempferi Plantation in Xiaolongshan, Gansu Province, China

Patterns of tree distribution are an important attribute of forest structure and directly affect the health and stability of forest ecosystems. This paper studied the effects of forest management on the forest distribution pattern of Larix kaempferi plantations with an aim to improve the quality of the spatial structure of plantations by providing scientific grounds for near-nature distribution pattern adjustment. We set up 15 long-term positioning and monitoring plots of 20 m × 20 m of L. kaempferi plantations in Xiaolongshan, Gansu Province, China, based on the Clark and Evans index, and applied the structure analysis method of the neighboring tree relationship to determine the standard angle of the uniform angle index of regularly distributed plantation forests. The changes in forest distribution patterns were compared before and after randomized management (R1 (dumbbell-shaped random unit), R2 (torch-shaped random unit) and R1:R2 = 1:2 models) and underlayer tending and unmanaged control (CK). The results showed that (1) Under different management modes, the distribution patterns obtained by the Clark and Evans index and the mean values of the uniform angle index were entirely the same; all stand patterns were evenly distributed. (2) Regardless of randomized management or underlayer tending, the number of trees in the even distribution was the largest, accounting for more than 40%. (3) The mean values of the uniform angle index of most stands increased obviously after randomized management, among which the R1 and R2 stands showed an upward trend, while the R1:R2 = 1:2 stands showed a slight decrease. However, the mean values of the uniform angle index of the stands with underlayer management showed a decreasing trend. (4) The proportion of random trees in most stands increased significantly after randomized management, increasing by 1%~19% compared with that before adjustment, while the proportion of random trees in the underlayer tending treatment decreased by 2%~10%. Our results suggest that (1) The method based on the modified uniform angle index standard angle could effectively improve the accuracy of the distribution pattern of individual trees in plantation forests and further improve the accuracy of the overall stand pattern quantitatively. (2) Randomized management significantly increased the proportion of random trees in the stands, which accelerated the evolution of the forest distribution pattern of the L. kaempferi plantation to a random distribution.