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Panax notoginseng (Burkill) F. H. Chen ex C. H. Chow ( P. notoginseng ) is a highly valued Chinese materia medica having a hemostatic effect and mainly used for the treatment of trauma and ischemic cardiovascular diseases. Stringent growth requirements, weak resistance to insect pests and plant diseases, arsenic contamination and continuous cropping constitute hurdles to further increases in the agricultural production of P. notoginseng . This review focuses on the traditional uses (based on traditional Chinese medicine theory), major chemical components, biological activities, pharmacological properties, geographical distributions and historical development of taxonomy of P. notoginseng and its related species in Panax genus, including Panax japonicus C. A. Meyer ( P. japonicus ), Panax japonicus C. A. Meyer var. major (Burkill) C. Y. Wu et K. M. Feng ( P. japonicus var. major ) and Panax japonicus C. A. Meyer var. bipinnatifidus (Seem.) C. Y. Wu et K. M. Feng ( P. japonicus var. bipinnatifidus ) are reviewed. This review sheds light on the origin herbs of Zhujieshen ( ZJS ) and Zhuzishen ( ZZS ), e.g., P. japonicas var japonicas , P. japonicus var. major and P. japonicus var. bipinnatifidus could be used as a substitute for P. notoginseng as hemostatic herbs. [ABSTRACT FROM AUTHOR]

The extensive abandonment of agricultural lands in the Mediterranean basin has led to large landscapes being dominated by early-successional species, characterized by high flammability and an increasing fire risk. This fact promotes fire occurrence and places ecosystems in a state of arrested succession. In this work, we assessed the effectiveness of several restoration actions in redirecting these ecosystems toward more resilient communities dominated by resprouting species. These actions included the mechanical clearing of early-successional species, the plantation of resprouting species, and the combination of both treatments. For 13 years, we assessed shifts in the successional trajectory and ecosystem flammability by changes in: species composition, species richness, ecosystem evenness, the natural colonization of resprouting species, total biomass and proportion of dead biomass. We observed that the plantation and clearing combination was a suitable strategy to promote resilience. Species richness increased as well as the presence of the resprouting species introduced by planting. The natural colonization of the resprouting species was also enhanced. These changes in the successional trajectory were accompanied by a possible reduction of fire risk by reducing dead fuel proportion. These findings are relevant for the management of Mediterranean basin areas, but also suggest new tools for redirecting systems in fire-prone areas worldwide. [ABSTRACT FROM AUTHOR]

Most palm oil currently available in global markets is sourced from certified large-scale plantations. Comparatively little is sourced from (typically uncertified) smallholders. We argue that sourcing sustainable palm oil should not be determined by commercial certification alone and that the certification process should be revisited. There are so-far unrecognized benefits of sourcing palm oil from smallholders that should be considered if genuine biodiversity conservation is to be a foundation of ‘environmentally sustainable’ palm oil production. Despite a lack of certification, smallholder production is often more biodiversity-friendly than certified production from large-scale plantations. Sourcing palm oil from smallholders also alleviates poverty among rural farmers, promoting better conservation outcomes. Yet, certification schemes – the current measure of ‘sustainability’ – are financially accessible only for large-scale plantations that operate as profit-driven monocultures. Industrial palm oil is expanding rapidly in regions with weak environmental laws and enforcement. This warrants the development of an alternative certification scheme for smallholders. Greater attention should be directed to deforestation-free palm oil production in smallholdings, where production is less likely to cause large scale biodiversity loss. These small-scale farmlands in which palm oil is mixed with other crops should be considered by retailers and consumers who are interested in promoting sustainable palm oil production. Simultaneously, plantation companies should be required to make their existing production landscapes more compatible with enhanced biodiversity conservation. [ABSTRACT FROM AUTHOR]

The United Nations Decade on Ecosystem restoration (2021¬–2030) lists mangrove ecosystems as a restoration priority. Interest in their conservation has increased recently due to their widespread degradation. Anthropogenic stressors and rehabilitation practices, specifically, have resulted in a significant decline in their species compositions. We investigated the knowledge gaps in terms of potential spatial diversity, intertidal zonation, and the historic state of mangrove forest species, and tested the role of environmental factors such as topography, as well as rehabilitation practices on diversity. Diversity and complexity indices, surface elevation, and species and structural diversities along three simplified transect lines over a broad geographical area and under various management practices were analyzed in Trat province, Thailand. Quantitative statistical zonation analyses within each transect and at the landscape-scale were performed using randomization tests and hierarchical cluster analysis. A modified "automatic regrowth monitoring algorithm (ARMA)," based on Landsat (1987–2020) and Sentinel-2 MSI (2015–2020) annual median composites was also used. Fifteen species were identified, with Ceriops tagal as the dominant species. Statistical analysis, however, failed to identify any significant zonation patterns at transect or landscape-scales at specific elevations. Rehabilitated and naturally regenerated stands showed gradual increases in their Normalized Difference Infrared Index over time. After 30 years, the rehabilitated stands made up of Rhizophoraceae monocultures were the same height as the adjacent natural stands. Depending on the location and propagule availability, the diversity and structure of regenerated stands exhibited high variation. Effluent from shrimp farms may have contributed to the disturbance of the forest stands and changes in shrimp farming practices could have facilitated their recovery. The results of the present study provide a valuable diversity baseline for the study site and secondary succession in rehabilitated and regenerated mangroves. The ARMA algorithm has also been confirmed as a valuable tool for future investigations of secondary succession and mangrove biodiversity status. [Display omitted] • Systematic transect line plots were established. • Effects of environmental and anthropogenic settings on mangrove species zonation and diversification were identified. • Time series data were utilized to monitor both the historic state and temporal dynamics. • A modified automatic regrowth monitoring algorithm (ARMA) was also developed. • Trajectories of change dynamics on mangrove ecosystems were also determined. [ABSTRACT FROM AUTHOR]

The carbon and nitrogen reserves of forest soil play a key role in combating global climate change. Afforestation is considered an effective measure for increasing carbon and nitrogen reserves in terrestrial forest ecosystems. However, the mechanisms governing how different developmental stages of plantations affect soil carbon and nitrogen stability and storage remain unclear. In this study, we selected three developmental stages of the Larix principis-rupprechtii plantations: medium mature forest (30 yr), near mature forest (40 yr) and mature forest (50 yr). We studied the distribution and stability of soil aggregates at distinct developmental stages, the distribution of carbon and nitrogen pools related to aggregates, and their relationship to environmental factors. We found that with increasing forest age, the soil sand particles became finer. In each developmental stage, the proportion of aggregates >0.25 mm reached more than 85%. The concentrations of carbon and nitrogen in the soil aggregates were lower in the near mature forest (40 a) than in the medium mature forest (30 a), but reached a maximum in the mature forest (50 a). There were significant positive correlations between soil carbon and nitrogen concentrations and soil relative water content (RWC), forest age, and stand density. Soil texture strongly affected the distribution of aggregates. TOC/TN was mainly influenced by aggregate distribution, which was most vulnerable to environmental factors. Environmental factors have a significant negative impact on soil texture, and the path coefficient was −0.812. Environmental factors indirectly affected the concentrations of soil carbon and nitrogen by influencing the distribution and stability of soil aggregates. Therefore, different developmental stages of plantations strongly affected forest carbon and nitrogen pools by changing the soil structure and environmental factors. This study provides a basis for understanding the mechanisms of forest soil carbon and nitrogen storage. • With the increase of forest age, the soil appeared fine-grained phenomenon. • Soil aggregate carbon and nitrogen pool concentration: mature forest > near mature forest > medium mature forest. • TOC/TN was the most important factor affecting the distribution of > 2 mm aggregates. • Environmental factors indirectly affect soil carbon and nitrogen pools by affecting soil aggregates. [ABSTRACT FROM AUTHOR]

Bamboo forests provide important ecosystem services and play an important role in terrestrial carbon cycling. Of the approximately 500 bamboo species in China, Moso bamboo ( Phyllostachys pubescens ) is the most important one in terms of distribution, timber value, and other economic values. In this study, we estimated current and potential carbon stocks in China's Moso bamboo forests and in their products. The results showed that Moso bamboo forests in China stored about 611.15 ± 142.31 Tg C, 75% of which was in the top 60 cm soil, 22% in the biomass of Moso bamboos, and 3% in the ground layer (i.e., bamboo litter, shrub, and herb layers). Moso bamboo products store 10.19 ± 2.54 Tg C per year. The potential carbon stocks reach 1331.4 ± 325.1 Tg C, while the potential C stored in products is 29.22 ± 7.31 Tg C a −1 . Our results indicate that Moso bamboo forests and products play a critical role in C sequestration. The information gained in this study will facilitate policy decisions concerning carbon sequestration and management of Moso bamboo forests in China. [ABSTRACT FROM AUTHOR]

Forest is an important part of the environmental system, which has a significant impact on soil hydrological characteristics and forest landscapes, because these processes are influenced by forest management and understory vegetation. Quantitative understory vegetation biomass (UVB) measurement and estimation are vital processes in forest ecology and environmental management. However, these estimations are difficult to make on a large scale especially dense planted forest. Here, we applied catchment-scale Structure from Motion and a manually operated ultralow-flying drone under the canopy of a dense planted (2000 stems/ha) Japanese cedar/cypress plantation forest to reconstruct the understory. An understory drone survey was performed over a 1.1-ha sub-catchment to generate a canopy height model based on dense point cloud data. A biomass survey of three 16-m2 harvesting plots was conducted to compute understory vegetation volume data based on point clouds. Combined with harvested biomass data in the field, quantitative models were developed between the understory vegetation volume and biomass. Subsequently, the models were used to map spatial understory vegetation biomass distribution in the sub-catchments. Aerial photos taken by the ultralow-flying drones under the canopy yielded a high-resolution catchment-scale understory with point cloud density >10/cm2. Strong cubic model coefficients of determination (R 2 = 0.75) predicted the understory vegetation biomass based on the canopy height model. The mean understory vegetation biomass was 0.82 kg/m2 and dominated by low ferns. In the present study, we successfully reconstructed the multilayered forest structure and generated understory vegetation biomass distribution models. This results also will be essential to evaluate the erosion and evapotranspiration in dense plantation forests and future environmental management. [Display omitted] • Achieved first understory biomass survey by drone under high-density forest canopy. • Applied high-density cloud point dataset in calculating understory vegetation volume. • Developed a model for predicting understory vegetation biomass. • Provided a new insight for understory biomass estimation and forest management. [ABSTRACT FROM AUTHOR]

The prevalence of forestry practices such as thinning and pruning have gradually decreased since the 1980s. Researchers have noted an increased flood risk with decreased forestry practices for coniferous plantations in Japan on the basis of infiltration and overland flow measurements at a plot scale (typically several square meters). However, no studies have examined changes in peak flow with decreased forestry practices at a watershed scale (typically several tens or hundreds of square kilometers) even though flood disasters generally occur at this scale in Japan. We examined changes in frequency distributions of daily precipitation (P) and runoff (Q) during the period 1979–2007 at the Terauchi watershed, where forestry practices are known to have decreased. For this purpose, we divided P and Q data into 14 and 15 classes according to the magnitude, respectively, and examined changes in the frequency for each class during the period. We observed no significant increasing trend for any P or Q class. Even when taking into account the effect of interannual variations in precipitation on the frequency for each Q class, there was no significant increasing trend in the frequencies except for two Q classes with moderate Q values. These results suggest that the increase in flood risk due to decreased forestry practices might be less than expected. [Copyright &y& Elsevier]

Abstract: Gum arabic yield, from Acacia senegal, and yield trends were studied at the Demokeya (13° 16′; 39° 29′E; Alt.560m) experimental site in Western Sudan. The effects of the date and intensity of tapping, rainfall and the minimum and maximum temperatures at tapping and gum collection on gum arabic yield were examined for eight years (1992–1999/2000) in a 12-year-old plantation. The objective of the study was to establish an understanding of the causes of variability in gum arabic yield and yield trends as a basis for yield control, prediction and stability. The results showed tapping dates produced roughly similar gum production patterns across years. Yield was found to be positively correlated with tapping intensity, rainfall and the minimum and maximum temperatures at tapping time, and negatively correlated with tapping time and the minimum and maximum temperatures at gum collection. The time of tapping, tapping intensity, rainfall and the maximum temperature at gum collection were found to explain 85% of the total variability in gum yield per unit area. The gum yield (g) of the first pick was highly correlated () with total yield (g/tree). The simple regression model based on this relationship was highly significant (). These models could help in understanding the causes of yield variability in gum arabic and can be used for estimating the yield of a current year based on the rainfall of the previous year under a prescribed plan of tapping. The yield of the current year can also be predicted using simple models based on the commencement of tapping and the yield of the first pick. In addition, the results can help to predict future gum yield depending on rainfall, temperature forecasts and the average tapping date and intensity used by gum farmers in western Sudan. [Copyright &y& Elsevier]

• Shade simplification is a manifestation of agricultural intensification. • Coffee is grown under natural shade and under silver oak shade. • Predatory function in coffee agroforests of two shade types is studied. • Predatory function is not affected by shade type in coffee. Agricultural intensification can decrease biodiversity and ecosystem services they deliver to agroecosystems. Diverse trees-shaded coffee is structurally and functionally complex and has biodiversity adequate for sustainable production of coffee and mitigation of biodiversity loss due to deforestation. However, shade tree simplification is intense in coffee agroforests worldwide, threatening their economic and environmental targets. In south India, native trees have been replaced by silver oak (Grevillea robusta) trees. Native trees-shaded coffee is floristically complex and diverse than oak-shaded coffee. We hypothesize that the natural prey removal fares better in native trees-shaded coffee than in oak-shaded coffee. Artificial caterpillar models of three colors were installed rotationally on leaves, stems, and branches of coffee plants in native trees-shaded- and oak-shaded coffee, and assessed the predation rates for fruiting and leaf-flushing periods of coffee to test this. Forty-four percent of the caterpillars were predated. Arthropods, and in particular the ants, were the predominant predators. Lizards followed by birds, and mammals were second, third, and fourth important predators of coffee agroforests. Overall, predation rates did not differ with the shade diversity, but lizard predation rates were higher in diverse trees-shaded coffee than in oak-shaded coffee. The predation rates were slightly higher in the fruiting season of coffee. Predation rates of any predator taxa were higher for the caterpillars placed on stems and branches than on leaves. The study does not support the hypothesis that the natural predation rates might be higher in floristically complex coffee agroforests, but highlights the biocontrol potential of lizards in diverse-shaded coffee. [ABSTRACT FROM AUTHOR]

Climate change is affecting the growth and distribution of trees in the Chinese boreal forest. Such changes in China, the southern terminus of the extensive Eurasian boreal forests, reflect on the changes that could occur further north under a warming climate. Most studies have found that tree growth increases with increasing temperature and precipitation in boreal forests, but there is little observational evidence of the climate thresholds that might slow these growth rates at the more extreme temperatures which are predicted to occur under future global warming. Here, we examine growth responses of this dominant boreal tree species (Larix gmelinii) to climate based on the data from plantation sample plots across a broad region (40° 51′–52° 58′N, 118° 12′E−133° 42′E) in northeast China. From statistically significant fits to quadratic equations, temperature and precipitation are the important climatic factors determining tree growth in L. gmelinii plantations at two age classes (<10 year and 10–30 year-old stands). The maximum rates of tree height and diameter at breast height (DBH) were about 0.53 m/year and 0.46 cm/year at <10 year stands, and about 0.63 m/year and 0.60 cm/year at 10–30 year stands, respectively. For stands with the highest values of mean annual increment (MAI), the corresponding optimal mean annual temperature (MAT opt) focused between 0.66 °C and 1.57 °C. The optimal mean annual precipitation (MAP opt) between 663 mm and 708 mm produced the maximal growth increments. With mean annual temperature of −2.4 °C and precipitation of 470 mm averaged over 1954–2005 in Chinese boreal forest region as baseline, we conservatively estimated that trees in Chinese boreal forest appear to have higher growth potentials with the maximum temperature increase of 3.6 °C and precipitation increase of 40%. • Temperature and precipitation are the key factors controlling Larix gmelinii forest. • The optimal temperature and precipitation are 0.66–1.57 °C and 663–708 mm. • Chinese boreal forest has higher growth with temperature +3.6 °C, precipitation +40%. [ABSTRACT FROM AUTHOR]