Enriquecimento de floresta em restauração por meio de semeadura direta de lianas

Leaf litter nutrient dynamics of Koompassia malaccensis and Shorea uliginosa in a tropical peat swamp forest of Peninsular Malaysia

Afforestation can increase soil organic carbon (SOC) storage, but the selection of tree species may be critical. This study explored soil CO2 production and effluxes in relation to SOC contents in temperate forests. Sites included even-aged (38 years) first generation stands of eight coniferous and two deciduous species planted at three sites along a gradient in soil fertility. SOC stocks (forest floor + mineral soil 0–50 cm) differed significantly between tree species, but soil type influenced SOC stocks the most. SOC stocks were significantly higher for stands on low-fertility sandy soils (141 ± 31 Mg C·ha–1) than stands on fertile loamy soils (62 ± 14 Mg C·ha–1). Soil CO2 effluxes were measured on two occasions in 2002 and varied between 18.7 and 36.3 kg C·ha–1·day–1. Variability within temperature-adjusted fluxes was not clearly related to tree species or soil type. Potential CO2 production rates in a laboratory incubation experiment (reported as CO2 produced per unit soil C) were mainly affected by site and were two times higher for soils from the nutrient-rich site compared with the most nutrient-poor site. Thus, the combined effect of contrasting CO2 production rates and stocks of soil C may explain the similar CO2 effluxes measured in the field. Results suggest that selection of soil type and tree species are important for SOC sequestration in future afforestation projects.

Urban tree transpiration (T) can significantly lower urban temperatures and mitigate the urban heat island effect. The careful selection of suitable tree species for the urban landscape holds immense significance in enhancing the quality of the human living environment. However, there remains a deficit of effective models capable of accurately assessing urban T and its associated cooling effects. In this study, we have developed a modified Priestley–Taylor (P–T mc ) model to assess T. This P–T mc model calculates the vegetation P–T coefficient ( α v ) through a machine learning technique that incorporates soil, meteorological, and vegetation parameters. Moreover, the P–T mc model integrates CO 2 concentration and flux data to enhance the precision of T simulations. Upon validation using data from two eddy correlation (EC) sites and stable hydrogen and oxygen isotope observation sites, it was demonstrated that the P–T mc model exhibits enhanced simulation capabilities for T when contrasted with the original P–T model. The root‐mean‐square error (RMSE) for the P–T mc model was determined to be 0.025 mm/hf in T simulation. The transpiration and cooling effectiveness of 19 representative urban tree species were further assessed using the P–T mc model framework. Among the selected 19 urban tree species, Ficus virens demonstrated the most impressive cooling performance. For Ficus virens, the average vegetation latent heat flux ( λT ) was measured at 6.18 MJ m 2 /d, while the temperature reduction (Δ T ) reached 4.66°C m 2 /d. In contrast, Palmae exhibited the least effective cooling, with average λT and Δ T values of only 0.89 MJ m 2 /d and 0.67°C m 2 /d, respectively. Correlation analysis indicated that the cooling effects of various urban tree species were primarily influenced by tree morphology. Specifically, higher values of leaf area index (LAI) and crown area ( C a ) were associated with better cooling performance, while increased tree height led to reduced cooling effectiveness. This study conducted a comprehensive evaluation of the cooling effects exhibited by diverse urban tree species through the utilisation of the proposed P–T mc model. The outcomes of our investigation offer a more robust scientific foundation for urban landscape planning and the selection of tree species.

Forests are the main components of terrestrial ecosystems and play an important role in the protection and construction of the national ecological security barrier. For a long time, China's large-scale afforestation had been practiced in areas with rainfall higher than the 400 mm threshold, but the issue of afforestation in high altitudes on the Tibetan Plateau remains elusive in both practical experience and theoretical exploration. It is worth thinking further about what principles should be followed in the selection of tree species and suitable altitudes for afforestation in high-altitude areas, as well as what experiences and lessons of previous afforestation efforts should be applied in high-altitude areas. As per the law of vegetation zonal distribution, this paper argues that afforestation at high altitudes should comply with the principle of vegetation zonal distribution and the low temperature limitation, and points out that afforestation is feasible only within the forest distribution area and below the altitudes of climate timberlines. Furthermore, we demonstrate the potential spatial areas of afforestation, and determine the local tree species that may be used for afforestation based on the existing problems of afforestation in eastern Tibet. In summary, afforestation in high-altitude areas of the eastern Tibetan Plateau must comply with the law of zonal vegetation distribution, focus on the upper limit of altitude and the selection of suitable tree species, and adopt only suitable native tree species.

This literature review presents information about the role of tree root systems for the functioning of agroforestry associations and rotations and attempts to identify root-related criteria for the selection of agroforestry tree species and the design of agroforestry systems. Tree roots are expected to enrich soil with organic matter, feed soil biomass, reduce nutrient leaching, recycle nutrients from the subsoil below the crop rooting zone and improve soil physical properties, among other functions. On the other hand, they can depress crop yields in tree-crop associations through root competition. After a brief review of favourable tree root effects in agroforestry, four strategies are discussed as potential solutions to the dilemma of the simultaneous occurrence of desirable and undesirable tree root functions: 1) the selection of tree species with low root competitiveness, eventually supplemented by shoot pruning; 2) the identification of trees with a root distribution complementary to that of the crops; 3) the reduction of tree root length density by trenching or tillage; and 4) the use of agroforestry rotations instead of tree-crop associations. The potential and limitations of these strategies are discussed, and deficits in current understanding of tree root ecology in agroforestry are identified. In addition to the selection of tree species and provenances according to root-related criteria, the development of management techniques that allow the manipulation of tree root systems to maximize benefit and minimize competition are proposed as important tasks for future agroforestry research.

The selection of suitable tree species and the reasonable allocation of planting areas are important measures for improving soil quality. This study aimed to investigate the characteristics of typical vegetation type soil quality differences and their dominant factors in loess hilly–gully areas after returning farmland to the forest (grassland). The soil quality status and dominant factors of arbors, shrubs and grasslands in the study area were comprehensively analyzed using the soil quality index (SQI) and structural equation modeling (SEM). The results showed the following: (1) In the study area, the shrub forest had a high capacity for air permeability, water retention and nitrogen fixation. (2) The soil quality of the three vegetation types improved with increasing precipitation, and the soil quality indicator of shrubs was the highest, indicating a better soil quality improvement. However, the soil quality of the arbors and grasslands showed a greater percentage increase. In the precipitation range of 400–410 mm, the soil quality of shrub forests was significantly higher than that of arbors and grasslands. (3) Structural equation modeling analysis indicated that precipitation, vegetation and soil factors are closely related to soil quality. Further analysis showed that soil bulk density, porosity, capillary water-holding capacity, soil organic carbon and total phosphorus were the dominant factors affecting the soil quality in the study area. The purpose of this study was to evaluate quantitatively the soil quality after different vegetation types under different precipitation gradients, to clarify the variation trend of soil quality at different vegetation types with different precipitation gradients and to provide a scientific basis and data support for the quantitative evaluation of vegetation restoration and selection of tree species and vegetation configuration within different precipitation gradients in loess hilly and gully regions in the future.

Exploring adaptation strategies of coffee production to climate change using a process-based model

Diverging effects of two contrasting tree species on soil and herb layer development in a chronosequence of post-agricultural forest

Monitoring of ambient air quality is done mainly to ensure whether the quality is acceptable and to prevent the deterioration of health. The monitoring of urban air quality requires sophisticated instruments to effectively monitor the ambient air. The present study has devised an alternative to the current situation where trees are used as an indicator of the study area using air pollution tolerance index. To understand the impact of air pollutants on the tree species at the study area near the rural school. Studies are carried out to determine the physiological responses and biochemical changes in the selected tree species near the rural school. The objective is to identify tolerance and sensitive tree species near the rural school using the air pollution tolerance index (APTI). The leaf samples were collected from the selected tree species which were used to determine the APTI through the biochemical parameters such as pH, ascorbic acid, total chlorophyll and relative water content. The response of the plants toward air pollution is assessed through APTI; tolerant species found are Albizia saman and Azadirachta indica, intermediate species Ficus religiosa and Syzygium cumini are in the category of intermediate and Tectona grandis is found to be sensitive species. The selected species were subjected to API for evaluation of the performance of the tree to recommend it for the green belt development. Based on the APTI, biological and socioeconomic importance, the selected tree species were graded and categorized based on their performance. Thus APTI and API determination provides the combating efficiency of the selected tree species against air pollution based on its biochemical characteristics, biological and socioeconomic importance. Tree species were also recommended for the green belt development in the study locale which will be effective in its purpose.KeywordsBio-indicatorsAir pollutionBio-accumulatorsGreen belt and tolerance

We continuously recorded the activity of adult and nymphal blacklegged ticks, Ixodes scapularis Say, exposed to diurnal light and temperature cycles in a laboratory test chamber by using a digital camera controlled by an intervalometer. Adult ticks collected and tested in the fall exhibited a bimodal pattern of activity, with peaks shortly after lights on and shortly after lights off, and substantial daytime activity. However, adult ticks collected in the winter and early spring exhibited a unimodal pattern of activity, peaking shortly after lights off, and minimal daytime activity. Nymphs, collected and tested in the summer, exhibited only a unimodal pattern of activity, peaking after lights off. Limited data also are presented for adult ticks exposed to only a temperature cycle or to only a light cycle in the spring. Ticks exposed to a temperature cycle exhibited a unimodal pattern of activity, similar to that exhibited by ticks exposed to both light and temperature cycles at the same time of year, whereas those exposed to a light cycle exhibited a bimodal pattern of activity. Although the difference did not quite reach statistical significance, there is a possibility that temperature is a stronger entraining agent for tick diurnal activity than is light, an unusual situation. The change in diurnal activity pattern from fall to spring suggests that ticks are adjusting their strategy for host finding, possibly in relation to remaining stored food supplies or host activity, and may have practical implications for sampling carried out to track tick populations.

We continuously recorded the activity of adult and nymphal blacklegged ticks, Ixodes scapularis Say, exposed to diurnal light and temperature cycles in a laboratory test chamber by using a digital camera controlled by an intervalometer. Adult ticks collected and tested in the fall exhibited a bimodal pattern of activity, with peaks shortly after lights on and shortly after lights off, and substantial daytime activity. However, adult ticks collected in the winter and early spring exhibited a unimodal pattern of activity, peaking shortly after lights off, and minimal daytime activity. Nymphs, collected and tested in the summer, exhibited only a unimodal pattern of activity, peaking after lights off. Limited data also are presented for adult ticks exposed to only a temperature cycle or to only a light cycle in the spring. Ticks exposed to a temperature cycle exhibited a unimodal pattern of activity, similar to that exhibited by ticks exposed to both light and temperature cycles at the same time of year, whereas those exposed to a light cycle exhibited a bimodal pattern of activity. Although the difference did not quite reach statistical significance, there is a possibility that temperature is a stronger entraining agent for tick diurnal activity than is light, an unusual situation. The change in diurnal activity pattern from fall to spring suggests that ticks are adjusting their strategy for host finding, possibly in relation to remaining stored food supplies or host activity, and may have practical implications for sampling carried out to track tick populations.

The altered proportion of Korean pine to broadleaved tree species following selective logging strongly affected post-harvest regeneration and species coexistence pattern in a temperate mixed broadleaved/Korean pine forest in eastern Eurasian. Species interaction should be considered when implementing selective logging schemes. It has been documented widely that selective logging can exert varied influences on post-harvested forest structure and dynamics via different logging intensity and rotation. However, few studies have been extended to evaluate the effects of the tree species selected for removal, which is also a critical component in prescribing a selective harvest plan. To clarify the effects and underlying mechanisms of logged tree species selection on species coexistence and regeneration pattern in post-harvested mixed broadleaved/Korean pine (Pinus koraiensis Siebold & Zucc.) forest in Changbai Mountains, China. Four types of plots were established based on different selection of logged tree species. Stand structure, spatial distribution pattern and spatial association of major tree species were analyzed using spatial point pattern (SPP) analysis. The effect of soil nitrogen concentration on forest regeneration was also examined through a Pearson correlation analysis. Sapling density of both Korean pine and commercially valuable broadleaved tree species was significantly greater on plots where Korean pines were logged than on plots where only commercial broadleaved trees were removed. Soil N and density of saplings were not correlated. SPP analysis showed strong negative spatial association between mature Korean pine and saplings of most tree species in most sampling plots. The proportion of Korean pine to broadleaved tree species selected for removal can lead to different stand structure and spatial distribution patterns of tree locations. Due to species–specific competition effects, such variations in spatial association of tree locations can exert varied effects on regeneration in this pine-dominated Eurasian temperate forest. To promote post-harvest tree regeneration and species coexistence, forest managers in this region should consider controlling the density of competition-superior trees such as large-size Korean pines when implementing a selective logging scheme.

Carbon storage and air pollution effect of urban trees and tree species selection: A case study in a typical city of the central Beijing-Tianjin-Hebei region

Both light and temperature can influence the pineal's synthesis of the indoleamine melatonin. An investigation of the effects of light and temperature cycles on the pineal melatonin rhythm (PMR) showed the following: (1) Both daily light cycles and daily temperature cycles could entrain the PMR; melatonin levels peaked during the dark phase of a light-dark cycle or the cool phase of a temperature cycle. (2) The PMR could be entrained by a temperature cycle as low as 2 degrees C in amplitude in lizards held in constant light or constant darkness. (3) The length of the photoperiod or thermoperiod affected the phase, amplitude, or duration of the PMR. (4) When presented together, the effects of light and temperature cycles on the PMR depended on the phase relationship between the light and temperature cycles, as well as on the strength of the entraining stimuli, such as the amplitude of the temperature cycle. (5) Exposure to a constant cold temperature (10 degrees C) eliminated the PMR, yet a rhythm could still be expressed under a 24-hr temperature cycle (32 degrees C/10 degrees C), and the rhythm peaked during the 10 degrees C phase of the cycle. (6) A 6-hr dark pulse presented during the day did not elicit a premature rise in melatonin levels. These studies show how environmental stimuli can control the pineal rhythm of melatonin synthesis and secretion. Previous studies have supported a model in which the lizard's pineal acts as a circadian pacemaker within a multioscillator circadian system, and have implicated melatonin as a hormone by which the pineal may communicate with the rest of the system. The lizard pineal, therefore, may act as a photo- and thermoendocrine transducer translating light and temperature information into an internal cue in the form of the PMR. The PMR, in turn, may control the phase and period of circadian clocks located elsewhere, insuring that the right internal events occur at the right time of day.

The study aimed to investigate the association of mosquito vector species with selected tree species at the Nigerian Defence Academy Ribadu Cantonment Kaduna. The study design was a Cross-sectional study primarily for distribution and relative abundance assessments. The study was carried out at the Nigerian Defence Academy Ribadu Cantonment, Kaduna, Nigeria. Mosquito samples were collected from the environment of tree species of interest using a mix of methods, as observed from several literatures. These include a yeast and sugar solution trap, a locally constructed hand-net, water-filled containers, and an ovipositing container. Following the mosquito collection on individual trees, physical and molecular identification were done using standard procedures. This was then succeeded by data analysis using Microsoft Excel 2016; descriptive statistics was used for summaries of the data and ANOVA, Chi square test were used to make inferences. A total of 2383 mosquitoes were collected from 140 tree samples of 10 different species. All the tree samples had different numbers of mosquitoes collected, with a variation in species. Terminalia ivorensis had the highest number of mosquitoes (631), and Eucalyptus camaldulensis had the lowest number (74). Using the Shanon Weiner Index calculator, the study was able to analyze the richness and evenness of mosquitoes to trees in the Cantonment. There is a significant relationship between different tree species and mosquito vectors within the Cantonment, and the degree to which mosquitoes are attracted to the tree species is based on specific characteristics of the tree species.