Search Results (881)

Pine stands affected by root and butt rot (Heterobasidion annosum s.l.) contain pines (Pinus sylvestris L.) that can survive for a long time without showing external symptoms of the disease (‘conditionally resistant’ refers to trees that survive without symptoms despite infection). The establishment of stands from the seeds of such trees can significantly increase the effectiveness of artificial afforestation. Since the growth and development of pine trees is determined to a certain extent by the number of cotyledons after seed germination, this article examines this trait in the progeny of trees that are potentially resistant and those that have already been attacked by root pathogens. The number of cotyledons and the resilience of trees is fascinating and not generally known. Presumably, the number of cotyledons can be linked to disease resistance based on increased vigour. Biologically, a larger area for carbon assimilation leads to better photosynthetic efficiency and the production of more assimilates (sugars) necessary to trigger defence processes in the event of infection. From an ecological point of view, this can give tree populations in areas potentially threatened by root system diseases a chance of survival. The aim of this study was to analyze the potential of using the number of cotyledons and other seedling characteristics to predict the resistance of trees to root and butt rot disease. The collected data show that the seedlings from the group of diseased trees exhibited lower growth rates and vigour. However, the seedlings from the group of potentially resistant trees are similar to the control, meaning the trees that show no disease symptoms because they have not come into contact with the pathogen. Our observations suggest that monitoring germinating cotyledons could serve as an early diagnostic tool to identify disease-resistant pines, although further research is needed. Full article

Afforestation in the transitional zone between the loess hilly area and the Mu Us Sandy Land of China has reshaped the landscape and greatly affected eco-hydrological processes. Plantations are crucial for regulating local net rainfall inputs, thus making it necessary to quantify the closure loss of plantation species in drought and semi-arid areas. To quantify and model the canopy interception of these plantations, we conducted rainfall redistribution measurement experiments. Based on this, we used the modified Gash model to simulate their interception losses, and the model applicability across varying rainfall types was further compared and verified. Herein, Caragana korshinskii, Salix psammophila, and Pinus sylvestris plantations in the Kuye River mountain tract were chosen to measure the precipitation distribution from May to October (growing season). The applicability of a modified Gash model for different stands was then evaluated using the assessed data. The results showed that the canopy interception characteristics of each typical plantation were throughfall, interception, and stemflow. The relative error of canopy interception of C. korshinskii simulated by the modified Gash model was 8.79%. The relative error of simulated canopy interception of S. psammophila was 4.19%. The relative error of canopy interception simulation of P. sylvestris was 13.28%, and the modified Gash model had good applicability in the Kuye River Basin. The modified Gash model has the greatest sensitivity to rainfall intensity among the parameters of the C. korshinskii and S. psammophila forest. The sensitivity of P. sylvestris in the modified Gash model is that the canopy cover has the greatest influence, followed by the mean rainfall intensity. Our results provide a scientific basis for the rational use of water resources and vegetation restoration in the transitional zone between the loess hilly region and the Mu Us Sandy Land. This study is of import for the restoration and sustainability of fragile ecosystems in the region. Full article

Subtropical moss peatlands have important ecological functions, and their protection and restoration are urgent. The lack of understanding of the biogeochemical changes in subtropical moss peatlands after human disturbance, particularly regarding their underground ecological changes, limits the efforts towards their protection and restoration. In this study, typical subtropical moss peatlands and the Cryptomeria swamp forest (CSF) formed by long-term (more than 20 years) drainage and afforestation in the Yunnan–Guizhou Plateau of China were selected as the research sites. Moreover, 16S rRNA high-throughput sequencing technology was used to study the differences in soil bacterial community diversity and composition among a natural Sphagnum fen (SF), Polytrichum bog (PB), and CSF to explore the effects of drainage and afforestation on different types of moss peatlands and its mechanism combined with soil physicochemical properties. Results showed that (1) drainage and afforestation significantly reduced the α diversity of soil bacterial communities in SF while significantly increasing the α diversity of soil bacterial communities in PB. Soil bacterial communities of SF had the highest α diversity and had many unique species or groups at different taxonomic levels. (2) The impact of drainage and afforestation on the soil bacterial community composition in SF was significantly higher than that in PB. Drainage and afforestation caused significant changes in the composition and relative abundance of dominant groups of soil bacteria in SF at different taxonomic levels, such as significantly reducing the relative abundance of Proteobacteria, significantly increasing the relative abundance of Acidobacteria, and significantly reducing the ratio of Proteobacteria to Acidobacteria, but did not have a significant impact on the corresponding indicators of PB. The changes in the ratio of Proteobacteria to Acidobacteria may reflect changes in the trophic conditions of peatlands. (3) Soil moisture content, available phosphorus content, and pH were key driving factors for changes in soil bacterial community composition and diversity, which should be paid attention to in the restoration of moss peatlands. This study provides insights into the protection and restoration of subtropical moss peatlands. Full article

Compared to agricultural environments, afforestation sites are more complex, often presenting issues such as undulating and uneven terrain. These conditions lead to instability in hole digging depth and plant spacing during continuous movement, and the hole shape may not meet expectations. Additionally, the hydraulic system exhibits slow response speed and long steady-state time, affecting the quality of sapling planting. To address these issues, this paper designs an intelligent planting control system for intermittent hole digging under continuous dynamic movement, based on a large tree planter. The focus is on studying the dynamic accuracy of the hole digging cylinder to resolve the instability of plant spacing and planting depth in actual planting processes. Firstly, a motion trajectory model of the intermittent hole digging mechanism is established to obtain the relationship between the displacement trajectory of the rotating cutter and the displacements of the floating cylinder and the hole digging cylinder. Secondly, a mathematical model of the electro-hydraulic servo system is established to control the dynamic accuracy of the hole digging operation. Finally, a Simulink simulation model of the system is established to analyze the performance indicators of the hydraulic system during operation using step and sinusoidal excitation signals. The test results show that the displacement of the hydraulic piston rod can ensure a linear extension trend within the range of 0 to 0.4 m, and the extension distance of the hole digging cylinder in the planting system is 0 to 0.35 m, ensuring linear change within this stroke. When the system’s extension command is 1 V, the actual output is 0.6 m, with a relative error of less than 10% compared to the simulation value, indicating that the control strategy can effectively improve the dynamic performance of the system. When the hydraulic system is in a steady-state extension state at 50 to 58.6 s, the relative error with the simulation value is 7.3%, meeting the “double ten indicators” requirement. The research results clearly verify the superior performance of the proposed intelligent control system, and the proposed control strategy has great potential in practical applications, promising to improve afforestation quality by stabilizing planting spacing and planting depth. Full article

Forest restoration projects can be categorized as climate projects, investments in the implementation of which exceed the investment costs of forest-climate projects, which reduces their attractiveness to investors. An algorithm for assessing investment costs of climate reforestation projects on disturbed lands has been developed. The potential of territories for the implementation of such project initiatives is available in all regions of Russia and amounts to more than 381 thousand hectares. For five studied polygons of disturbed lands (Kuzbass basin, Moscow basin, Western Siberia basin, as well as basins of Chelyabinsk and Belgorod Regions), the aggregated costs for the implementation of measures to create carbon-depositing plantations and ground cover were calculated. Investment costs for restoration of 1 hectare of disturbed land under the climate project vary from 82.6 thousand rubles to 116.9 thousand rubles. Cost analysis shows that the carbon intensity of investment in such projects on disturbed lands is quite high (Ccii > 1.0). The highest investment potential is observed in the Kuzbass basin, where Ccii is 2.01. To organize and implement the afforestation project on disturbed lands of the Kemerovo Region, investments in the amount of 66.7 thousand rubles/ha for capital expenditures and 24.7 thousand rubles/ha for current expenses will be required. The payback period of such an investment project, taking into account the discount rate, is 13.1 years, and during the study period (20 years) the income from the project will cover 228% of the spent funds. These data confirm that the investment potential of forest-climatic projects on disturbed lands is quite high. Full article

Afforestation (AF) in farmland has been widely used as an alternative and sustainable land-use practice to address socioeconomic and environmental challenges. The aim of this study is to estimate farmers’ willingness to accept (WTA) compensation and land, both of which are equally significant for policymakers to ensure the effective implementation of AF and achieve desired outcomes. This topic has not been sufficiently explored in previous research. This study focused on areas characterized by insecure farming conditions, backward economies, and fragile landscapes, where farmers are generally unfamiliar with AF or compensation for ecosystem services under payment for ecosystem services programs. It assessed their attitudes towards the WTA AF, compensation, and land as an alternative practice, which remains under-researched. This is crucial for designing effective AF programs in the future to improve livelihood and enhance the quantity and quality of the environment. This study used the contingent valuation method to estimate the minimum WTA compensation and maximum land for the forgone loss and alternative land-use practices. A questionnaire survey was conducted in Hupsekot municipality, Nepal, with 232 farmer households. The ordinal logistic regression model was used to analyze influencing factors of WTA compensation and land. The result showed that farmers’ average WTA compensation was NPR 1268.67 (USD 9.76)/Kattha/year, with 2.64 Kattha land available for AF. The factors, including socioeconomic characters and attitudes toward the environmental situation and forests, significantly influenced WTA values and provided potential target factors to achieve maximum AF land within a lower budget. Full article

Comprehensively clarifying the influencing factors of carbon emissions is crucial to realizing carbon emission reduction targets in China. To address this issue, this paper develops a four-level carbon emission influencing factor system from six perspectives: population, economy, energy, water resources, main pollutants, and afforestation. To analyze how these factors affect carbon emissions, we propose an improved partial least squares structural equation model (PLS-SEM) based on a random forest (RF), named RF-PLS-SEM. In addition, the entropy weight method (EWM) is employed to evaluate the low-carbon development level according to the results of the RF-PLS-SEM. This paper takes Shandong Province as an example for empirical analysis. The results demonstrate that the improved model significantly improves accuracy from 0.8141 to 0.9220. Moreover, water resources and afforestation have relatively small impacts on carbon emissions. Primary and tertiary industries are negative influencing factors that inhibit the growth of carbon emissions, whereas total energy consumption, the volume of wastewater discharged and of common industrial solid waste are positive and direct influencing factors, and population density is indirect. In particular, this paper explores the important role of fisheries in reducing carbon emissions and discusses the relationship between population aging and carbon emissions. In terms of the level of low-carbon development, the assessment system of carbon emission is constructed from four dimensions, namely, population, economy, energy, and main pollutants, showing weak, basic, and sustainable stages of low-carbon development during the 1997–2012, 2013–2020, and 2021–2022 periods, respectively. Full article

Nitrogen (N) fertilization promotes morphofunctional attributes that enhance plant performance under stress conditions, but the amount and form supplied modify the magnitude of plant responses. We assessed several morpho-physiological and biochemical responses of Prosopis laevigata seedlings to a high supply of N, provided as either inorganic (NH₄NO₃) or organic (amino acids). Such N treatments were applied on four-month-old seedlings as a supplement of 90 mg N to a regular supply of 274 mg N plant⁻¹. Nitrogen supply modified biomass allocation patterns between leaves and roots regardless of N form. Increased N input decreased photosynthetic capacity, even when plants had high internal N reserves. Organic N fertilization reduced the N use efficiency, but increased leaf and root amino acid concentrations. Proteins accumulated in stems in plants receiving inorganic N, while the organic N increased leaf proteins. High N supply promoted root starch accumulation irrespective of N form. Nitrogen supply did not directly influence plants’ regrowth capacity. Still, resprouting was correlated to initial root-to-shoot ratios and root starch, confirming the importance of roots as storage reserves of starch for recovering biomass after browsing. These findings have practical implications for designing nutritional management strategies in nurseries to improve seedling performance in afforestation efforts. Full article

Gansu Province in China has the characteristics of an underdeveloped economy, low forest carbon sink, and rich non-fossil energy, making it a typical area for research to achieve the “double carbon” target. In this paper, the primary energy consumption and carbon emissions and their development trends in Gansu Province during the “double carbon” target period were predicted by the fixed-base energy consumption elasticity coefficient method, and the possibility of achieving the “double carbon” target in Gansu Province was explored. In the three hypothetical scenarios, it was estimated that the total primary energy consumption of Gansu Province will be 91.9–94.81 million tons of standard coal by 2030 and 99.35–110.76 million tons of standard coal by 2060. According to the predicted share of different energy consumption in Gansu Province, the CO₂ emissions of Gansu Province in the three scenarios were calculated and predicted to be between 148.60 and 153.31 million tons in 2030 and 42.10 and 46.93 million tons in 2060. The study suggests that Gansu Province can reach the carbon peak before 2030 in the hypothetical scenarios. However, to achieve the goal of carbon neutrality by 2060, it was proposed that, in addition to increasing carbon sinks by afforestation, it is also necessary to increase the share of non-fossil energy. As long as the share is increased by 0.3% on the basis of 2030, the goal of carbon neutrality by 2060 in Gansu Province can be achieved. The results show that the increase in the share of non-fossil energy consumption is the most important way to achieve the goal of carbon neutrality in Gansu Province, and it also needs to be combined with the optimization of industrial structure and improvement of technological progress. Based on the research results, some countermeasures and suggestions are put forward to achieve the goal of carbon neutrality in Gansu Province. Full article

Terrestrial ecosystems play a critical role in the global carbon cycle, and their carbon sequestration capacity is vital for mitigating the impacts of climate change. Changes in land use and land cover (LULC) dynamics significantly alter this capacity. This study scrutinizes the LULC evolution within the Beijing metropolitan region from 1992 to 2022, evaluating its implications for ecosystem carbon storage. It also employs the Patch-Generating Land Use Simulation (PLUS) model to simulate LULC patterns under four scenarios for 2035: an Uncontrolled Scenario (UCS), a Natural Evolution Scenario (NES), a Strict Control Scenario (SCS), and a Reforestation and Wetland Expansion Scenario (RWES). The InVEST model is concurrently used to assess and forecast ecosystem carbon storage under each scenario. Key insights from the study are as follows: (1) from 1992 to 2022, Beijing’s LULC exhibited a phased developmental trajectory, marked by an expansion of urban and forested areas at the expense of agricultural land; (2) concurrently, the region’s ecosystem carbon storage displayed a fluctuating trend, peaking initially before declining, with higher storage in the northwest and lower in the central urban zones; (3) by 2035, ecosystem carbon storage is projected to decrease by 1.41 Megatons under the UCS, decrease by 0.097 Megatons under the NES, increase by 1.70 Megatons under the SCS, and increase by 11.97 Megatons under the RWES; and (4) the study underscores the efficacy of policies curtailing construction land expansion in Beijing, advocating for sustained urban growth constraints and intensified afforestation initiatives. This research reveals significant changes in urban land use types and the mechanisms propelling these shifts, offering a scientific basis for comprehending LULC transformations in Beijing and their ramifications for ecosystem carbon storage. It further provides policymakers with substantial insights for the development of strategic environmental and urban planning initiatives. Full article

Forest change affects local and global climate by altering the physical properties of the land surface. Accurately assessing urban forest changes in local land surface temperature (LST) is a scientific and crucial strategy for mitigating regional climate change. Despite this, few studies have attempted to accurately characterize the spatial and temporal pattern of afforestation, reforestation, and deforestation to optimize their effects on surface temperature. We used the China Land Cover Dataset and knowledge criterion-based spatial analysis model to map urban forestation (e.g., afforestation and reforestation) and deforestation. We then analyzed the impacts of these activities on LST from 2010 to 2020 based on the moving window strategy and the spatial–temporal pattern change analysis method in the urban agglomerations of the Yangtze River Delta (YRD) and Pearl River Delta (PRD), China. The results showed that forest areas declined in both regions. Most years, the annual deforestation area is greater than the yearly afforestation areas. Afforestation and reforestation had cooling effects of −0.24 ± 0.19 °C and −0.47 ± 0.15 °C in YRD and −0.46 ± 0.10 °C and −0.86 ± 0.11 °C in PRD. Deforestation and conversion of afforestation to non-forests led to cooling effects in YRD and warming effects of 1.08 ± 0.08 °C and 0.43 ± 0.19 °C in PRD. The cooling effect of forests is more evident in PRD than in YRD, and it is predominantly caused by reforestation. Moreover, forests demonstrated a significant seasonal cooling effect, except for December in YRD. Two deforestation activities exhibited seasonal warming impacts in PRD, mainly induced by deforestation, while there were inconsistent effects in YRD. Overall, this study provides practical data and decision-making support for rational urban forest management and climate benefit maximization, empowering policymakers and urban planners to make informed decisions for the benefit of their communities. Full article

This study aimed to evaluate the emergence, early growth, and anatomy of Schinus terebinthifolia Raddi cultivated in iron mining tailings. The seeds were obtained from trees used in urban afforestation and cultivated on two substrates: sand and iron mining tailings. The chemical composition of the mining tailing was characterized. The experiment was conducted in a growth room for 60 days. The emergence rate, seedling survival, height, number of leaves, chlorophyll content, and leaf and root anatomy were evaluated. The analysis of the composition of the mining tailings indicated that macro- and micronutrients were present, as well as potentially toxic elements such as Al, Cd, Cr, and Pb. The mining tailings reduced the emergence rate, and 25% of the seedlings died in this substrate. In addition, the mining tailings promoted a significant reduction in all parameters investigated, including seedling height, number of leaves, chlorophyll content, total leaf thickness, abaxial and adaxial epidermis thickness, palisade parenchyma thickness, and the length and width of the seeds. Additionally, the chloroplasts, the metaxylem vessel diameter, and the phloem proportion were evaluated. Interestingly, the tailings promoted an increase in the secretory channel. In the roots, no significant changes were observed in the parameters analyzed. Thus, the seeds of S. terebinthifolia germinated in the iron mining tailings, and 75% of the seedlings survived, showing their potential for reforestation. Nonetheless, iron mining tailings exhibited toxicity to S. terebinthifolia seedlings, reducing their photosynthetic tissues and, consequently, their growth; this toxicity is likely related to potentially toxic elements present in tailings. Full article

This study investigates how digital inclusive finance, financial development, and technology influenced forest and timber outputs across 31 provinces in China from 2011 to 2021. The findings, derived from panel quantile regression analysis, indicate that digital inclusive finance significantly enhances forest economic output, particularly in regions with lower economic activity, by improving access to critical financial resources such as credit and investment. However, the positive effects diminish at higher levels of economic activity, suggesting potential diminishing returns. Through the marketization of credit distribution and diverse financial instruments, financial development is essential for promoting sustainable forestry practices and adopting new technologies. Based on the findings, the study suggests expanding digital financial services in areas with low forest activity to help people access credit and investments, boosting forest productivity. It also recommends improving financial markets and investing in new forestry technologies to support better forest management and timber production. Full article

Biological soil crusts (BSCs) serve important functions in conserving biodiversity and ecological service in arid and semi-arid regions. Afforestation on shifting sand dunes can induce the formation of BSC on topsoil, which can accelerate the restoration of a degraded ecosystem. However, the studies on microbial community succession along BSC development under sand-fixation plantations in desertification areas are limited. This paper investigated the soil properties, enzymatic activities, and bacterial and fungal community structures across an age sequence (0-, 10-, 22-, and 37-year-old) of BSCs under Caragana microphylla sand-fixation plantations in Horqin Sandy Land, Northeast China. The dynamics in the diversities and structures of soil bacterial and fungal communities were detected via the high-throughput sequencing of the 16S and ITS rRNA genes, respectively. The soil nutrients and enzymatic activities all linearly increased with the development of BSC; furthermore, soil enzymatic activity was more sensitive to BSC development than soil nutrients. The diversities of the bacterial and fungal communities gradually increased along BSC development. There was a significant difference in the structure of the bacterial/fungal communities of the moving sand dune and BSC sites, and similar microbial compositions among different BSC sites were found. The successions of microbial communities in the BSC were characterized as a sequential process consisting of an initial phase of the faster recoveries of dominant taxa, a subsequent slower development phase, and a final stable phase. The quantitative response to BSC development varied with the dominant taxa. The secondary successions of the microbial communities of the BSC were affected by soil factors, and soil moisture, available nutrients, nitrate reductase, and polyphenol oxidase were the main influencing factors. Full article

Pinus yunnanensis Franch., one of the pioneer species of wild mountain afforestation in southwest China, plays an essential role in the economy, society and environment of Yunnan Province. Nonetheless, P. yunnanensis’ trunk twisting and bending phenomenon has become more common, which significantly restricts its use and economic benefits. In order to clarify the compositional differences between the straight and twisted trunk types of P. yunnanensis and to investigate the reasons for the formation of twisted stems, the present study was carried out to dissect the macroscopic and microscopic structure of the straight and twisted trunk types of P. yunnanensis, to determine the content of cell wall components (lignin, cellulose, hemicellulose), determine the content of endogenous hormones, and the expression validation of phytohormone-related differential genes (GA2OX, COI1, COI2) and cell wall-related genes (XTH16, TCH4). The results showed that the annual rings of twisted trunk types were unevenly distributed, eccentric growth, insignificant decomposition of early and late wood, rounding and widening of the tracheid cells, thickening of the cell wall, and reduction of the cavity diameter; the lignin and hemicellulose contents of twisted trunk types were higher; in twisted trunk types, the contents of gibberellin (GA) and jasmonic acid (JA) increased, and the content of auxin (IAA) was reduced; the GA2OX were significantly down-regulated in twisted trunk types, and the expressions of the genes associated with the cell wall, COI1, COI2, TCH4 and XTH16, were significantly up-regulated. In conclusion, the present study found that the uneven distribution of endogenous hormones may be an important factor leading to the formation of twisted trunk type of P. yunnanensis, which adds new discoveries to reveal the mechanism of the genesis of different trunk types in plants, and provides a theoretical basis for the genetic improvement of forest trees. Full article