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Mild cognitive impairment (MCI) is a condition that impairs activities of daily living, and often transforms to dementia. Repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) show promise in improving cognitive functions in MCI patients. In this meta-analysis, we aimed to compare the effects of rTMS and tDCS on memory functions in MCI patients. We explored eight databases from their inception to March 16, 2024. We obtained 11 studies with 406 patients with MCI. We used the standardized mean difference (SMD) with a 95% confidence interval (CI) to synthesize the effect size. rTMS and tDCS significantly improved memory functions in MCI patients (SMD = 0.61; 95% CI: 0.41–0.82; p

Ship piping arrangement is a nondeterministic polynomial problem. Based on the advantages of the grey wolf optimization (GWO) algorithm, which is simple, easy to implement, and has few adjustment parameters and fast convergence speed, the study adopts the grey wolf optimization (GWO) algorithm to solve the ship piping arrangement problem. First, a spatial model of ship piping arrangement is established. The grid cell model and the simplified piping arrangement environment model are established using the raster method. Considering the piping arrangement constraint rules, the mathematical optimization model of piping arrangement is constructed. Secondly, the grey wolf optimization algorithm was optimized and designed. A nonlinear convergence factor adjustment strategy is adopted for its convergence factor. Powell’s algorithm is introduced to improve its local search capability, which solves the problem that the grey wolf algorithm easily falls into the local optimum during the solving process. Simulation experiments show that compared with the standard grey wolf algorithm, the improved algorithm can improve the path layout effect by 38.03% and the convergence speed by 36.78%. The improved algorithm has better global search ability, higher solution stability, and faster convergence speed than the standard grey wolf optimization algorithm. At the same time, the algorithm is applied to the actual ship design, and the results meet the design expectations. The improved algorithm can be used for other path-planning problems.

Vegetation change has a non-negligible role in the impact of ecosystem services (ESs). Quantitative assessment of vegetation ecosystem services is the basis for sustainable regional development. Using the Chinese Loess Plateau (LP) as the study area, this study firstly analysed the spatial and temporal characteristics of vegetation change and used a Geodetector model to reveal the driving mechanism. Next, this study applied the InVEST model to quantitatively assess the four services of carbon storage, habitat quality, soil conservation and water yield, and explored the vegetation ecosystem service balance through vegetation type transfer. The results showed that (1) there was a trend towards an increase in the area of all vegetation types, with sparse vegetation being the most pronounced. Areas of damaged vegetation were concentrated in urban and peripheral areas, as well as wasteland and bare ground. (2) Annual precipitation, soil types and cumulative afforestation area ratio were the main drivers of vegetation change on the LP. (3) Restoration of woodland enhanced carbon storage, habitat quality and soil retention services for vegetation on the LP, while water yield decreased by 31.66%. The restoration of vegetation area did not enhance all ecosystem services. This study may provide a reference and basis for the sustainable management of regional ecosystems.

Accumulation of vegetation biomass is a crucial process for carbon fixation in the early stage of afforestation and a primary driving force for subsequent ecological functions. Accurately assessing the storage and allocation of elements in plantations is essential for their management and estimating carbon sink capacity. However, current knowledge of the storage and allocation patterns of elements within plant organs at the community level is limited. To clarify the distribution patterns of elements in plant organs at the community level, we measured the biomass within plant organs of five typical plantations in the early stage of afforestation in the loess hilly-gully region. We assessed the main drivers of element accumulation and distribution by employing redundancy analysis and random forest. Results revealed significant differences in biomass storages among plantations and a significant effect of plantation type on the storages of elements within plant organs. Furthermore, the dominant factors influencing C–N–P storage and allocation at the community level were found to be inconsistent. While the storage of elements was mainly influenced by stand openness, total soil nitrogen, and plant diversity, the allocation of elements in organs was mainly influenced by stand openness and soil water content. Overall, the spatial structure of the community had an important influence on both element storage and allocation, but soil conditions played a more important role in element allocation than in storage. Random forest results showed that at the community level, factors influencing element storage and allocation within plant organs often differed. The regulation of elemental storage could be regulated by the major growth demand resources, while the allocation was regulated by other limiting class factors, which often differed from those that had a significant effect on element storage. The differences in plant organ elemental storage and allocation drivers at the community level reflect community adaptation strategies and the regulation of resources by ecosystems in combination with plants. Our study provides valuable insights for enhancing plantation C sink estimates and serves as a reference for regulating element storage and allocation at the local scale.

The forest ecosystem is the ecosystem with the largest terrestrial carbon pool in the world. Afforestation, cutting and tending mutually affect the forest carbon source and the carbon sink. However, few studies have explored the effects of larch plantation management on soil aggregate stability and soil aggregate carbon storage. The effects of the four thinning intensities (unmanaged control (CK), 15% reduction, mild thinning (LT), 30% reduction, intermediate thinning (MT), and 50% reduction, severe thinning (HT)) on soil aggregate stability and carbon storage were investigated in Larix principis-rupprechtii plantations in North China. The results showed that soil aggregates with a particle size of >2 mm or 1–2 mm under all thinning intensities were the most abundant. At the same time, organic carbon and labile carbon were mainly distributed in >0.25 mm soil aggregates. The MT treatment corresponded with the highest organic carbon and labile carbon levels. The distribution of soil macro aggregates was greatly affected by stand density, while the distribution of micro aggregates was most affected by nutrient-related factors. Forest thinning reduces the stability of soil aggregates, though intermediate thinning can improve the carbon sequestration potential of soil aggregates. These findings will provide essential evidence for carbon sequestration of soil aggregates in plantations after thinning, and provide reference for those formulating plantation management strategies in North China.

Nitrogen (N), phosphorus (P), and potassium (K) play an essential role in plant growth, development and reproduction. The pattern of nutrient stoichiometry across various plant organs and plant life forms can reflect the trade-off of plant growth strategies. However, there is a lack of systematic research on plant nutrient stoichiometry and the influence of environmental factors. Therefore, the main forest type Quercus wutaishanica community was considered as the object for this study and samples of different life forms (trees, shrubs, herbs) and different organs (leaves, stems, roots, seeds) were collected in northern China. First, we analyzed N/P/K stoichiometry among different organs and different life forms in the Quercus wutaishanica natural community. Second, we explored the influence of environmental factors on N/P/K stoichiometry and clarified the relative contributions of variables among different life forms. The results showed that the distributions of nutrient stoichiometry in different life forms and organs were different. As the most active organ, the content of elements in leaves was significantly higher than that in other organs. Among them, P was the main limitation in leaves and roots; N was the main limitation in stems and seeds in this area. Environmental factors had different effects on the N/P/K stoichiometry of different life forms. The nutrient stoichiometry in trees was mainly affected by topographical factors; the nutrient stoichiometry in shrubs and herbs was mainly affected by soil factors. Therefore, the differences in N, P, and K stoichiometry may be caused by the growth environment and the plant’s own adaptation strategies. All of these studies provide new insight for studying the homeostasis system within plants and communities by means of stoichiometry. This study is expected to guide the management and protection of the natural community, make the natural community give more ecological functions, and provide support for the cultivation of artificial forests in the future.

In the past few decades, dominating human development patterns have negatively affected ecosystem services (ESs). To sustainably supply multiple ESs and enhance human well-being, researchers should analyze ESs responses to antagonistic effects. This study uses the InVEST model to evaluate the key ESs of the Shanxi Province in 2000 and 2020. The geographical detector model was used to analyze the dominant factors of the spatial differentiation characteristics of ESs changes. We used the Multi-Scale Geographically Weighted Regression (MGWR) to identify the main drivers of ESs changes and capture the differences in spatial variation. The results were as follows: (1) From 2000 to 2020, soil conservation (SC), carbon storage (CS), grain productivity (GP), and total ecosystem services (TES) increased by 44.48%, 1.03%, 57.84, and 1.67% respectively. Water yield (WY) and habitat quality (HQ) decreased by 1.36% and 0.64%, respectively. (2) The interaction of anthropogenic, climate, vegetation, and geomorphological factors has a significantly greater impact for the spatial differentiation of ESs changes than any single factor, though anthropogenic factors dominate the spatial distribution of regional ESs changes. (3) There is obvious spatial heterogeneity in the properties and intensity of the correlations between driving factors and changes in ESs. Anthropogenic factors have significant negative effects on CS, WY, and HQ changes. Vegetation factors were the main driving force for the improvement of GP and TES, while the climatic factor was the main driving factor for SC changes. (4) The MGWR model achieved the optimal performance, and the four selected driving factors explain 61.9%, 81.3%, 97.1%, 56.7%, 81.6%, and 79.2% of the changes in CS, WY, SC, HQ, GP, and TES, respectively. Based on the results, we suggest that future ecosystem management, planning and decision making, should focus on maintaining the balance between anthropogenic activities and vegetation restoration. This study provides a convenient method to capture the relationship between ESs and drivers in geographic space, and provides a reference for the sustainable supply of ESs in the region and the world.

It is acknowledged that trees biomass allocation in response to environmental conditions. However, it remains poorly understood what strategies of plant biomass allocation with inter- and intraspecific interactions of tree species in forest stands. Such information is important for revealing strategies of plant biomass allocation with plant competition. To address this problem, a study was conducted in Larix principis-rupprechtii plantations to evaluate the impact of plant competition on plant biomass allocation in Shanxi Province, China. We measured a competition index (CI), stem, branch, foliage, and root biomass as well as element content (Carbon (C), Nitrogen (N), Phosphorus (P), Potassium (K)). Stem-foliage ratio (S/F), aboveground–belowground biomass ratio (T/R), average annual increment of biomass (AAB), height (AAH), and DBH (AAD) were calculated. The study found that the competition intensity of neighboring trees was closely related to the partitioning of biomass. Our results demonstrated that competition pressure of neighboring trees was a crucial factor to drive and regulate the distribution of biomass. Predicting biomass allocation–competition relationships could represent a supportive method for improving management of Larix principis-rupprechtii plantations in Mountain Taiyue areas.

Ecological engineering is a widely used strategy to address environmental degradation and enhance human well-being. A quantitative assessment of the impacts of ecological engineering on ecosystem services (ESs) is a prerequisite for designing inclusive and sustainable engineering programs. In order to strengthen national ecological security, the Chinese government has implemented the world’s largest ecological project since 1999, the Grain for Green Program (GFGP). We used a professional model to evaluate the key ESs in Lvliang City. Scenario analysis was used to quantify the contribution of the GFGP to changes in ESs and the impacts of trade-offs/synergy. We used spatial regression to identify the main drivers of ES trade-offs. We found that: (1) From 2000 to 2018, the contribution rates of the GFGP to changes in carbon storage (CS), habitat quality (HQ), water yield (WY), and soil conservation (SC) were 140.92%, 155.59%, −454.48%, and 92.96%, respectively. GFGP compensated for the negative impacts of external environmental pressure on CS and HQ, and significantly improved CS, HQ, and SC, but at the expense of WY. (2) The GFGP promotes the synergistic development of CS, HQ, and SC, and also intensifies the trade-off relationships between WY and CS, WY and HQ, and WY and SC. (3) Land use change and urbanization are significantly positively correlated with the WY–CS, WY–HQ, and WY–SC trade-offs, while increases in NDVI helped alleviate these trade-offs. (4) Geographically weighted regression explained 90.8%, 94.2%, and 88.2% of the WY–CS, WY–HQ, and WY–SC trade-offs, respectively. We suggest that the ESs’ benefits from the GFGP can be maximized by controlling the intensity of land use change, optimizing the development of urbanization, and improving the effectiveness of afforestation. This general method of quantifying the impact of ecological engineering on ESs can act as a reference for future ecological restoration plans and decision-making in China and across the world.

Forest soils sequester a large amount of carbon (C) and have a significant effect on the global C balance. Forests are commonly managed to maintain certain age structures but the effects of this management on soil C pools (kg C m−2) is still uncertain. We compared 40-year-old (1GF) and 24-year-old (2GF) plantations of Larix principis-rupprechtii in North China. Specifically, we measured environmental factors (e.g., soil temperature, moisture, and pH), the active C and nitrogen (N) pools (e.g., soil organic C, soil total N, dissolved organic C and N, microbial biomass C and N), and soil processes (e.g., C mineralization and microbial activity in different seasons) in five soil layers (0–50 cm, 10 cm for each soil layer) across the growing seasons in three 25 m × 25 m plots in each age class (1GF and 2GF). Findings indicated that the soil organic C pool in the older 1GF forest (12.43 kg C m−2) was significantly higher than 2GF forests (9.56 kg C m−2), and that soil temperature in 1GF forests was 9.8 °C, on average, 2.9% warmer than temperature in 2GF forests. The C lost as carbon dioxide (CO2) as a result of mineralization in the 2GF plots may partly explain the lower soil organic C pool in these younger forests; microorganisms likely drive this process.

Background Soil microbial communities and their associated enzyme activities play key roles in carbon cycling in terrestrial ecosystems. Soil microbial communities are sensitive to resource availability, but the mechanisms of microbial regulation have not been thoroughly investigated. Here, we tested the mechanistic relationships between microbial responses and multiple interacting resources. Methods We examined soil carbon properties, soil microbial community structure and carbon-related functions under nitrogen addition and plant inputs removal (litter removal (NL), root trench and litter removal (NRL)) in a pure Larix principis-rupprechtii plantation in northern China. Results We found that nitrogen addition affected the soil microbial community structure, and that microbial biomass increased significantly once 100 kg ha−1 a−1 of nitrogen was added. The interactions between nitrogen addition and plant inputs removal significantly affected soil bacteria and their enzymatic activities (oxidases). The NL treatment enhanced soil microbial biomass under nitrogen addition. We also found that the biomass of gram-negative bacteria and saprotrophic fungi directly affected the soil microbial functions related to carbon turnover. The biomass of gram-negative bacteria and peroxidase activity were key factors controlling soil carbon dynamics. The interactions between nitrogen addition and plant inputs removal strengthened the correlation between the hydrolases and soil carbon. Conclusions This study showed that nitrogen addition and plant inputs removal could alter soil enzyme activities and further affect soil carbon turnover via microbial regulation. The increase in soil microbial biomass and the microbial regulation of soil carbon both need to be considered when developing effective sustainable forest management practices for northern China. Moreover, further studies are also needed to exactly understand how the complex interaction between the plant and below-ground processes affects the soil microbial community structure.

Changes in the concentration of soil nitrogen (N) or its components may directly affect ecosystem functioning in forestry. Thinning of forest stands, a widely used forestry management practice, may transform soil nutrients directly by altering the soil environment, or indirectly by changing above- or belowground plant biomass. The study objectives were to determine how tree stem density affects the soil N pool and what mechanisms drive any potential changes. In this study, N and its active components were measured in the soil of a Larix principis-rupprechtii plantation across two full growing seasons, in 12 (25 × 25 m) plots: (low thinning, removal of 15% of the trees, three plot repetitions), moderate thinning (MT) (35% removal) and heavy thinning (HT) (50% removal) and no thinning control. Environmental indices, like the light condition, soil respiration, soil temperatures, and prescription, were measured in the plots also. Results indicated that soil total nitrogen (STN) was affected by tree stem density adjustments in the short-term; STN generally increased with decreasing tree stem density, reaching its highest concentration in the MT treatment before decreasing in HT. This pattern was echoed by the DON/STN ratio dissolved organic nitrogen (DON) under MT. A lower DON/STN was measured across the seasons. Microbial biomass nitrogen (MBN) and the SOC/STN (soil organic carbon (SOC)) ratio and density treatments influenced MBN concentration and inhibited SOC/STN. MT tended to accumulate more STN, produce lower DON/STN and had a generally higher microbial activity, which may be partly ascribed to the higher MBN value, MBN/STN ratio and lower DON/STN. The water conditions (soil moisture), light and soil temperatures could partly be responsible for the N pool dynamic in the different density treatments.

Patterns of biomass and carbon (C) storage distribution across Chinese pine (Pinus tabulaeformis) natural secondary forests are poorly documented. The objectives of this study were to examine the biomass and C pools of the major ecosystem components in a replicated age sequence of P. tabulaeformis secondary forest stands in Northern China. Within each stand, biomass of above- and belowground tree, understory (shrub and herb), and forest floor were determined from plot-level investigation and destructive sampling. Allometric equations using the diameter at breast height (DBH) were developed to quantify plant biomass. C stocks in the tree and understory biomass, forest floor, and mineral soil (0-100 cm) were estimated by analyzing the C concentration of each component. The results showed that the tree biomass of P. tabulaeformis stands was ranged from 123.8 Mg·ha-1 for the young stand to 344.8 Mg·ha-1 for the mature stand. The understory biomass ranged from 1.8 Mg·ha-1 in the middle-aged stand to 3.5 Mg·ha-1 in the young stand. Forest floor biomass increased steady with stand age, ranging from 14.9 to 23.0 Mg·ha-1. The highest mean C concentration across the chronosequence was found in tree branch while the lowest mean C concentration was found in forest floor. The observed C stock of the aboveground tree, shrub, forest floor, and mineral soil increased with increasing stand age, whereas the herb C stock showed a decreasing trend with a sigmoid pattern. The C stock of forest ecosystem in young, middle-aged, immature, and mature stands were 178.1, 236.3, 297.7, and 359.8 Mg C ha-1, respectively, greater than those under similar aged P. tabulaeformis forests in China. These results are likely to be integrated into further forest management plans and generalized in other contexts to evaluate C stocks at the regional scale.

Ecosystems provide a wide range of benefits to society. Ecosystem services related to water supply are now a hot topic in ecology and hydrology. Calculation and mapping of water supply services are of great importance to water resource planning and management as well as in hydropower station construction. Recent efforts have called for the integration of the values of these ecosystem services in order to improve decision making in social and economic issues, but so far few practical efforts have been demonstrated of such an approach. Quantifying levels and values of these services has proven difficult. In this study, we used a spatially explicit modelling tool, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST), to predict changes in ecosystem water supply services under different land use and land cover scenarios in the past (year 2003, LULC0), present (year 2013, LULC1) and for a sustainable development scenario focusing on ecosystem protection and restoration (year 2013, LULC2) in Liaoheyuan watershed, China. The datasets used for this model include land use and land cover, average annual precipitation, annual reference evapotranspiration, depth to root restricting layer, the amount of available plant water, watersheds and subwatersheds, a seasonality factor and other variables. The results show that total water yield in the watershed under LULC0, LULC1 and LULC2 was 36.6, 33.62, and 34.07million m³·y-1, respectively. The water supply ranged from 31.50million m³·y-1 for the LULC1 to 34.33million m³·y-1 for the LULC0. The total annual value of water supply services in the Liaoheyuan watershed was approximately 7.09E+05 RMB·y-1in LULC0, 6.51E+05 RMB·y-1in LULC1, and 6.60E+05 RMB·y-1 in LULC2 (1 US$ = 6.3 RMB). Our study provides an example for understanding how ecosystem processes determine the provision of ecosystem services and benefits to society in the Liaoheyuan watershed. More broadly, quantifying ecosystem services in a spatially explicit manner can provide crucial scientific support for more effective, efficient and defensible water resources management. [ABSTRACT FROM AUTHOR]

We investigated how factors underlying local spatial variations controlled needle litter decomposition across a chronosequence of Chinese pine (Pinus tabuliformis Carr.) forests. Litterbag methods were used to measure changes in litter chemistry and the mass loss of leaf litter, as well as selective biotic and abiotic factors during the growing seasons (May-October) in 2013 and 2014 in a set of fully replicated P. tabuliformis Carr. secondary forest stands that differ in age in northern China. During the two growing seasons the path analysis identified the litter lignin/N ratio, soil microbial metabolic quotient (qCO2), soil diversity of fungal assemblages (SFD), and soil-water content (SWC) as dominant controlling factors in needle litter decomposition, collectively explaining 76.9% of the total variation in mass loss across the entire age sequence. Litter lignin/N and soil qCO2 had the greatest negative effects on the k value, followed by weaker positive effects of SFD and SWC. Our findings indicate that forest stand age has a great influence on needle litter decomposition by determining litter quality, with soil microbial activity and local environmental factors being secondary drivers in needle litter decomposition across a chronosequence of Chinese pine (Pinus tabuliformis Carr.) forests. [ABSTRACT FROM AUTHOR]

Although the effect of litter mixture on decomposition has been well documented, few studies have examined the relationships between richness and relative abundance of leaf species in litter mixture and changes in universal fungal communities during the decomposition process in temperate forests. In this study, we used the litterbag method and included three leaf litter species, i.e., aspen (Populus davidiana Dode), birch (Betula platyphylla Sukaczev) and oak (Quercus mongolica Fischer ex Ledebour), to investigate the mass loss rate and diversity of universal fungal communities in each litter treatment, which were sampled in situ after 180, 240, 300 and 360 days of decomposition (between 2012 and 2013) in broadleaved mixed forests in Chinese temperate forests. Eight mixture proportions were examined: pure aspen litter (10A), pure birch litter (10B), pure oak litter (10O), 50% aspen litter mixed with 50% birch litter (5A:5B), 50% aspen litter mixed with 50% oak (5A:5O), 50% birch litter mixed with 50% oak litter (5B:5O), 10% birch litter mixed with 80% aspen litter and 10% oak litter (1B:8A:1O), 30% birch litter mixed with 40% aspen litter and 30% oak litter (3B:4A:3O). Over 360 days of decomposition, approximately 46.6%, 43.6%, 28.0%, 54.4%, 40.2%, 39.5%, 54.5% and 49.46% of litter mass was lost from 10A, 10B, 10O, 5A:5B, 5A:5O, 5B:5O, 1B:8A:1O and 3B:4A:3O, respectively. In addition, the number of fungal denaturing gradient gel electrophoresis (DGGE) bands showed a positive correlation with mass loss rate, indicating a positive feedback between leaf litter decomposition and universal fungal communities in the leaf litter. The results revealed that the 5A:5B, 1B:8A:1O and 3B:4A:3O litter mixtures had a synergistic effect on the litter mixture, while the 5A:5O and 5B:5O litter mixtures had a nearly neutral effect on the litter mixture. Thus, leaf litter species composition and relative abundance seem to be more important than leaf litter richness in driving the direction and magnitude of litter mixture decomposition. [ABSTRACT FROM AUTHOR]

Litter quality is often considered the main driver of rates of decomposition. Litter decomposes faster in its home environment than in any other environment, which is called the home-field advantage (HFA). However, evidence for this phenomenon has not been universal. In addition, litter mixtures of different species can induce a non-additive effect (NAE) on decomposition processes. However, the direction and magnitude of NAE vary and underlying mechanisms remain unclear. The aim of our study was to assess the effect of litter quality on leaf-litter decomposition in the context of HFA and NAEs in temperate forests in China. Litterbags containing aspen (Populus davidiana), birch (Betula platyphylla), and oak (Quercus liaotungensis) litter were incubated in situ in pure aspen and broadleaved mixed forests in Chinese temperate forests for 360 days. The main results were: 1. Aspen litter with a low C/N ratio and high initial N concentration decomposed faster than birch litter, both of which decomposed faster than oak litter, which had the lowest quality. 2. The rate of decomposition of oak litter was significantly higher in the broadleaved mixed forest than in pure aspen stands; however, the rate of decomposition of birch litter was not significantly different from pure aspen stands and broadleaved mixed forest. 3. Contrary to what was predicted, the mixture of aspen and birch litter decomposed faster than expected. However, both the aspen/oak and birch/oak mixtures had a neutral mixing effect where the rates of decomposition were slightly faster than expected. 4. Controlling factors based on linear models show that the order of the relative importance of their effect on litter decomposition was as follows: litter quality, forest floor environment, and litter mixtures. This study indicates that: 1. The various litter species exhibited different litter-environment interactions, such as favoring or contradicting the HFA hypothesis. 2. Litter mixture treatments can induce different mixing effects. 3. Compared with environment and litter mixtures, litter quality is the dominant factor in controlling the rate of litter decomposition. [ABSTRACT FROM AUTHOR]

Knowledge about the impact of nitrogen (N) addition on soil respiration (Rs) is critical for understanding soil carbon (C) balance and its responses to climate change. We conducted a long-term field experiment to evaluate the response of Rs to N addition in a larch (Larix principis-rupprechtii) plantation during the growing season in northern China. We applied four N (in the form of NH4 NO3 ) levels, i.e., control (N0: 0 g N m-2 year-1 ), low-N (N1: 5 g N m-2 year-1 ), medium-N (N2: 10 g N m-2 year-1 ), and high-N (N3: 15 g N m-2 year-1 ) monthly starting in June 2015. The results showed that N addition – especially N2 and N3 levels – significantly stimulated Rs. N1 and N2 levels resulted in the increase of Rs in a short time, whereas the duration of N3 level can last across the whole month or at least 10 days. The results highlight the need for improving the Rs sampling interval after N addition to ensure more accurate evaluation of C emission. Soil temperature and soil moisture together explained more variations of Rs. N addition exhibited a slight increase in the sensitivity of Rs to temperature (Q10 ), but no significant differences were found for the Q10 among N levels [ABSTRACT FROM AUTHOR]