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Non-structural carbohydrates (NSCs) can reflect the balance of resource allocation and trade-offs, as well as the adaptability of plants to the environment. Alterations in environmental conditions across an elevation gradient may impact the carbon balance within leaves. Nonetheless, it remains highly uncertain whether the effect of elevation on NSCs differs among species and sexes. To reveal the response patterns of leaf NSCs in dioecious plants with elevation, Populus cathayana Rehd. and Hippophae rhamnoides L., distributed at four elevations in the subalpine region of western Sichuan, China, were selected, and female and male leaves were sampled and measured for their contents of NSCs, soluble sugar, and starch. Meanwhile, the relationships of NSCs, soluble sugar, and starch with leaf nitrogen and phosphorus were analyzed. The results showed that the elevational patterns of NSCs were mainly dependent on species and were slightly affected by sex. Leaf NSCs in both sexes of P. cathayana did not exhibit significant linear changes, whereas those in H. rhamnoides increased significantly and linearly with elevation. For P. cathayana, a significant increase in leaf starch with elevation was only found in female plants and may benefit from phosphorus deficiency, as it was significantly negatively correlated with phosphorus. However, leaf soluble sugar and starch between sexes of H. rhamnoides showed similar patterns of significant increases with elevation, and they were not correlated significantly with nitrogen and phosphorus. This might be due to H. rhamnoides, which is a nitrogen-fixing plant and thereby did not show deficiencies or limitations in nitrogen and phosphorus, as shown by the decreased or unchanged elevational patterns of nitrogen/phosphorus, starch/phosphorus, and soluble sugar/phosphorus. Overall, our results emphasize that species, rather than sex, is an important factor influencing the elevational pattern of NSCs, but for specific species, such as P. cathayana, in this study, there was a divergence in the elevational response of the allocation of starch and soluble sugar between sexes, reflecting the specific adaptive strategies of different plant species or sexes in response to changes in the growing environment. [ABSTRACT FROM AUTHOR] more...

Microbial residues are an important component of soil organic carbon (SOC). It is unclear how long-term thinning affects the accumulation characteristics of microbial residue carbon (C). We analyzed the differences in soil physicochemical properties, microbial communities, extracellular enzyme activities, and microbial residue C in topsoil (0-10 cm) and subsoil (20-30 cm) in Picea asperata plantation of non-thinned (control, 4950 trees ⋅ hm-2) and thinned for 14 years (1160 trees ⋅ hm-2) stands, aiming to reveal the regulatory mechanism of thinning on microbial residue C accumulation. The results showed that thinning significantly increased SOC content, total nitrogen content, available phosphorus content, the proportion of particulate organic C, soil water content, C-cycle hydrolase, and acid phosphatase activities, but significantly reduced the proportion of mineral-associated organic C. Thinning significantly affected the content of fungal and microbial residue C, and the contribution of microbial residue C to SOC, and these effects were independent of soil layer. The content of fungal and microbial residue C was 25.0% and 24.5% higher under thinning treatments. However, thinning significantly decreased the contribution of microbial residue C to SOC by 12.3%, indicating an increase in the proportion of plant-derived C in SOC. Stepwise regression analysis showed that total nitrogen and soil water content were key factors influencing fungal and microbial residue C accumulation. In summary, thinning promoted microbial residue C sequestration by altering soil properties and changed the composition of SOC sources. [ABSTRACT FROM AUTHOR] more...

In the green economy, strategic emerging industries to implement Class II green technological innovation keep critical to obtain competitive advantages. The government regulation could effectively make up for the shortcomings of the negative externalities of green technological innovation. In order to further explore the impact of government regulation on Class I, II and III green technological innovation of strategic emerging industries, this article utilizes the strategic emerging industries as the main experimental subject. Through constructing a tripartite evolutionary game model of strategic emerging industries, the government and consumers, it reveals the process of the three-party discretionary selection in the process of green technology innovation, and acquires equilibrium strategies of the tripartite in the process of green technological innovation. more...

The digital transformation of manufacturing industry accelerates the collaborative innovation of multi-agent value co-creation, which makes the influence of subject heterogeneity on the innovation performance in digital innovation become a focus issue in both theory and practice. This paper builds a conceptual model of subject heterogeneity in digital collaborative innovation influence on the innovation performance from target heterogeneity, knowledge heterogeneity and organization heterogeneity three dimensions, which based on the perspective of the behavior subjects in manufacturing digital innovation of value co-creation. Then we deeply explore the influence mechanism between the heterogeneous cooperative innovation behavior of heterogeneous value subject and the innovation performance in digital innovation. The research results are helpful to realize higher quality digital cooperation among manufacturing enterprises, promote the coordinated development of digital value chain, and improve the digital innovation performance. more...

Soil greenhouse gas (GHG) fluxes relate to soil carbon and nitrogen budgets and have a significant impact on climate change. Nevertheless, the temporal variation and magnitude of the fluxes of all three major GHGs (CO2, CH4 and N2O) and their influencing factors have not been elucidated clearly in primary forests on the eastern Qinghai-Tibetan Plateau. Herein, field chamber GHG fluxes from May to November, soil microbial community and enzyme activity were analyzed in a fir-dominated (Abies fargesii var. faxoniana) primary forest. The emission rates of CO2 and N2O ranged between 64.69–243.22 mg CO2 m−2 h−1 and 1.69–5.46 ug N2O m−2 h−1, exhibiting a temporally unimodal pattern with a peak in July. The soil acted as a CH4 sink, and the uptake rate varied between 52.96 and 84.67 μg CH4 m−2 h−1 with the higher uptake rates in June and November. The temporal variation in the CO2 flux was significantly correlated with the geometric mean of enzyme activities, suggesting that the soil CO2 flux was determined by microbial activity rather than soil microbial biomass. The soil N2O flux was positively related to nitrate concentration with marginal significance, probably because N2O was a byproduct of nitrification and denitrification processes. The soil CH4 uptake was closely associated with methanotrophic biomass (18:1ω7c). The results highlight divergent temporal dynamics of GHG fluxes owing to different driving mechanisms and an important CH4 sink in the primary forest soil, helping to evaluate the carbon and nitrogen budgets of primary forests on the eastern Qinghai-Tibetan Plateau. [ABSTRACT FROM AUTHOR] more...

Elevation plays a pivotal role in modulating hydroclimatic dynamics, changing vegetation activity and shaping vegetation distribution patterns in alpine regions. Nevertheless, a conspicuous knowledge gap persists regarding the interaction between climate drivers on vegetation activity. In this study, we investigated the spatio-temporal patterns of the Normalized Difference Vegetation Index (NDVI), a proxy for vegetation activity, and examined its interactions with temperature (T) and precipitation (P) along elevational gradient (EG) in the Alpine and Sub-alpine Woodlands of Southwest China (ASWSC) during 2001–2018. We found that approximately 24% vegetation in ASWSC exhibited significant greening trend, as a result of regional warming and slight wetting during the study period. The greening and browning rates were both elevational asymmetric, with higher rates at lower elevations. We also illustrated an alternating domination of T - P on vegetation activity along EG. This suggested a roughly antagonistic effect between the two drivers within the whole vegetation elevation range except for a synergistic effect in the sub-alpine forests zone between 2300 - 4200 m. The antagonistic effect tended to be more pronounced in warm and dry years, while the synergistic effect was more evident in cold and wet years. Specifically for different vegetation types, we found an insignificant T - P interactive effect along EG in indigenous evergreen needleleaf forest (ENF) and evergreen broadleaf forest (EBF), in contrast to the significant synergistic effect in the regenerated deciduous broadleaf forest (DBF) and mixed forest (MF) and antagonistic effect in shrubland and grassland types. In summary, our study revealed alternating-dominant effects of temperature and precipitation on vegetation activity along EG. These findings will deepen our understanding of vegetation resistance and resilience to climate change and eventually contribute to establishing a scientific foundation for effective ecosystem management and conservation practices in alpine region. • The greening and browning rates were both elevational asymmetric, with higher rates at lower elevations. • Alternating domination of temperature - precipitation on vegetation activity along elevational gradients. • Antagonistic effect of T and P was enhanced in warm and dry years, synergistic effect was enhanced in cold and wet years. [ABSTRACT FROM AUTHOR] more...

• The forest productivity of mixed plantations was 18–39.5% greater than that of pure plantations. • Understory vegetation diversity in MCC was significantly higher than in PCL and PCF, by 15.8–20% and 13.2–35.7%, respectively. • The water conservation capacity of MCC is significantly higher (by 19.4–42.9%) than that of PCL and PCF. • Performance against the soil fauna diversity index was similar in all three stands. Many studies of biodiversity-ecosystem functioning (BEF) relationships indicate that mixed plantations can enhance ecological benefits by enabling ecological niche differentiation between species. However, few studies explore multi-dimensional evidence to fully evaluate the integrated ecological benefits of mixed plantations. This paper aims to assess the stand characteristics and ecological benefits of different forest types, drawing on multiple lines of evidence (trees, shrubs, herbs, soil fauna, and soils) to understand the effects of mixed plantations on integrated ecological benefits. Our study focused on pure Cunninghamia lanceolata (Chinese Fir) plantations (PCL), pure Cryptomeria fortunei (Chinese Cedar) plantations (PCF), and mixed C. lanceolata - C. fortunei plantations (MCC), which are common in the mountainous areas of the Sichuan Basin in southwestern China. We analysed the growth status, spatial structure, understory vegetation diversity, soil fauna characteristics, and physical and chemical soil properties found in plots representing these three forest types. The results showed that productivity was significantly higher in the MCC than in PCL or PCF, by 39.5% and 18%, respectively. Mixed plantations showed higher stand growth rates, but this effect was limited by interspecific competition. The results further showed that mixed plantations promote forest growth by allocating spatial locations between different tree species. In addition, the spatial stand structure in the mixed plantations was more stable than that in the two pure plantations, and the management potential of the mixed plantations was greater. Understory vegetation in MCC was significantly more diverse than in PCL and PCF, by 15.8–20% and 13.2–35.7%, respectively. Moreover, mixed plantations performed better in terms of soil water and soil fertility. Interestingly, we found no difference in soil fauna diversity between mixed and pure plantations. We conclude that, overall, planting mixed plantations can enhance the integrated ecological benefits of afforestation and may be an essential strategy for ensuring that plantations can cope with climate extremes. [ABSTRACT FROM AUTHOR] more...

The triangular arrow from thin to thick indicates that the value of a variable gradually increases, the shape from thin to thick to thin indicates that the value of the variable increases and then decreases. [Display omitted] • Soil micro-food web attributes and soil multifunctionality (SMF) exhibited a similar single hump-shaped pattern with increasing elevation. • Multitrophic composition and multitrophic diversity indirectly driven SMF through soil micro-food web complexity. • The soil micro-food web complexity was of greater importance in regulating SMF. Variations in soil micro-food web characteristics under changing environments can exert profound consequences on soil multifunctionality. However, the intrinsic relationship between these changes and their dependence on long-term environmental factors remains largely unquantified. Here, we investigated the soil micro-food web attributes (i.e., multitrophic diversity, multitrophic composition and network complexity) and multiple types of soil functions (soil multifunctionality) along an elevation gradient on the Eastern Tibetan Plateau. The results showed that elevation significantly affected the multitrophic composition, and multitrophic diversity, soil micro-food web complexity and soil multifunctionality exhibited a similar single hump-shaped pattern with increasing elevation. Compared to multitrophic composition and multitrophic diversity, the soil micro-food web complexity was significantly and positively correlated with soil multifunctionality and was of greater importance in regulating soil multifunctionality. However, multitrophic composition and multitrophic diversity indirectly driven soil multifunctionality through soil micro-food web complexity. This empirical evidence demonstrates that soil micro-food web complexity is a better predictor of soil functions than the multitrophic composition and diversity metrics that have been commonly used in previous studies. In conclusion, our findings highlighted the perceived importance of soil micro-food web complexity in regulating soil multifunctionality in forests under changing environments. [ABSTRACT FROM AUTHOR] more...