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In order to solve the problem in that the classical forest land expectation value method ignores the actual forest stock volume when assessing the income at the end of the current production cycle in the forest, and fill the research gap in this area, the technical system of the forest land asset evaluation was enriched. The forest land returns were divided into two parts, i.e., the segmented forest land return price from the growth of the actual forest stand to the end of the growth cycle (Bu1), and the segmented forest land return price for an infinite number of growth cycles after the growth of the actual forest stand to the end of the growth cycle (Bu2). Through structure, the forest land gain price expansion model was obtained, and the stand quality including the average diameter at breast height, average height, stock volume, and outturn of stand as dummy variables were used to construct the growth harvest model related to asset evaluation. Taking Cunninghamia lanceolata forest land as an example, the traditional asset evaluation methods were comparatively analyzed. The residual standard deviation (RSD) of the growth model was less than 10%, the total relative error (TRE) and mean system error (MSE) were within ±10%, the mean prediction errors (MPE) were less than 5%, and the mean percentage standard errors (MPSE) were less than 10%, respectively. Combining the forest land net present value expansion model with the traditional evaluation method, the evaluation value of the forest land assets was subsequently calculated, and accordingly, the forest land asset evaluation prime stand factors were predicated. It was found that the valuation results of the forest land net present value expansion model were consistent with the actual situation. The forest land net present value expansion model can therefore be used for asset evaluation of tree forest land (including natural uneven-aged forest land), bamboo forest land, shrub forest land, and economic forest land, and provide new technical support for forest land asset evaluation.

Long-term monocultures of tea and the excessive use of chemical fertilizer lead to the degradation of soil quality. Improving the soil quality of ex-tea plantations through vegetation restoration is an important task. However, the changes in soil nutrients, fungal communities, and the effects of microorganisms on soil nutrients after reforestation remain unclear. Therefore, in this study, we aimed to explore the effects of Pinus and Chinese fir on soil nutrients and fungal communities in ex-tea plantation areas that were subjected to the reforestation modes of pure forest and mixed forest by measuring soil chemical properties and ITS rRNA gene sequences. The results showed that (1) after reforestation, the relative normalized difference vegetation index (NDVI) of the Mixed forest, Mixed Pine and Mixed Fir areas increased (p < 0.05) compared to that of pure forest; (2) the soil organic carbon (SOC), total nitrogen (TN), and N:P ratios of the mixed forest increased by an average of 54%, 90%, and 299% (p < 0.05) compared to pure forest, whereas the total phosphorus (TP) and available potassium (AK) decreased by an average of 39% and 89% (p < 0.05); and (3) there was no significant difference in the diversity of the fungal communities of the pure and mixed forests, but the fungal phyla Mucoromycota, Glomeromycota, and Rozellomycota were significantly different in the pure and mixed forests. This differing microbial composition led to a significant increase (p < 0.05) in symbiotrophs (ecotomycorhizal, ericoid mycorhizal) in the mixed forest, which was negatively correlated with the soil TP and positively correlated with the TN and the N:P ratio. In addition, there was also a significant decrease (p < 0.05) in complex nutrient types (ectomycorrhizal-fungal parasite-plant saprotroph-wood saprotroph), which were negatively correlated with the SOC and TN, and arbuscular mycorrhizas, which were positively correlated with the TP. Our results show that the chemical properties of soils and the structure of the fungal communities changed significantly due to the reforestation of Chinese fir and Pinus, and the mixed forest mode of reforestation was more conducive to improving the soil quality; therefore, a mixed forest of Chinese fir and Pinus can be used to improve degraded soils in ex-tea planting areas.

In traditional observation schemes of stellar refraction navigation, the accuracy was limited due to unreasonable observation directions. In order to ameliorate this situation, a method of refracted starlight observation based on observability analysis is proposed. The function of this method is optimally generating an observation attitude sequence according to standard trajectories of spacecraft so that the selection of a refracted starlight observation sequence can be realized. Specifically, the improvement of Fisher information matrix calculation enables this method to be qualified for the navigation problem with unsteady measurement quantities as well as the non-fully observability which is defined as the capability of estimating the system state through measurements in finite time. Here, we construct a quantitative relationship between refracted starlight measurements and system observability by means of Fisher information index ( FII). Next, the observation scheme is retrieved by searching the maximum value of the optimized variable, which includes the ( FII). Finally, we resort to the extended Kalman filter to accomplish typical trajectory navigation simulations of the observation scheme. The results indicate that our method brings more accuracy than traditional ones in estimation of position and velocity of the optimal observation scheme.

In recent years, nanofluid has gradually entered people's field of vision due to its unique cold storage performance. Hybrid nanofluid has a more prominent effect. In order to reduce the supercooling degree of the nanofluid and obtain a practical and effective method to reduce the supercooling degree, the nano-particle graphene oxide and Al2O3 are added into deionized water ultrasonically to configure the nanofluid, and then the temperature is cooled. The effect of nanofluid concentration and different initial fluid temperature on the nanofluid subcooling degree is obtained when the ultrasonic time is 120min; when the nanofluid concentration is 0.15%wt, the nanofluid subcooling degree is the lowest, and the nanofluid is supercooled at this time The temperature is 2.8°C, which is the optimal condition for undercooling research.

The aim of this study was to explore the soil microbial variability within different forest ecosystems (evergreen broad-leaf forest (EBF), coniferous forest (CF), subalpine dwarf forest (SDF) and alpine meadow (AM) at different altitudes in mid-subtropics of China. The phospholipid fatty acid (PLFA) method was used to analyze the microbial communities in rhizosphere soil under different forest types. The relationships were also analyzed between the microbial diversity and soil nutrients. A total of 27 PLFA biomarkers were detected and the PLFA concentrations decreased in the sequence of bacteria > fungus > actinomycete > protozoa in all forest types. The microbial communities in the soil under all forest types were distinct. The predominant microflora in all soils were 18:1ω9c, 16:1ω7c, cy19:0, a17:0 and 18:0. The indexes of Simpson, Shannon-Wiener and Brillouin of soil microbial community diversity in these four forest types all showed a trend of EBF > CF > SDF > AM. According to principal component analyses (PCA), the variable variances of principal components 1 and 2, which were related to the PLFA biomarkers of soil microorganisms, were 67.67% and 17.91%, respectively. Furthermore, the total PLFAs of different soil microbial groups showed a correlation with soil nutrients and enzyme activities in all forest types. The soil microbial diversity gradually decreased in the order of EBF > CF > SDF > AM in the Daiyun Mountains. Different vegetation types affect soil microbial community composition and diversity by changing the soil physicochemical properties and enzyme activity.

Aboveground plant parts can trap moving sediment on slopes during concentrated water runoff, resulting in the formation of sediment mounds around plants. Plant morphological and functional traits may influence these sediment trapping patterns. Characterizing the sediment trapping abilities of common plants is of great interest when selecting appropriate plant species for erosion control. Predicting plant sediment trapping abilities using fractal dimensions of sediment particle size distribution could enhance the management and restoration of degraded lands with declining vegetation coverage in dry-hot valleys. Using flume experiments, we studied sediment retention abilities in six common plant species: the tree species Leucaena leucocephala and Melia azedarach; the shrub species Dodonaea viscose and Coriaria sinica; and the graminoids Heteropogon contortus and Eulaliopsis binate. Sediment trapping mass was measured at two ages (three-month-old and one-year-old seedlings). The particle size distribution of trapped sediment was determined using a laser particle size analyzer. The fractal characterizations (singular- and multi-fractal dimensions) of sediment particle size distribution were calculated using the fractal scale theory. Statistical analyses were performed to compare sediment trapping mass and the fractal characterizations in the six species at the two ages. C. sinica had the highest relative trapped sediment at both ages. Trapped sediment mass of one-year-old seedlings were significantly related to the singular fractal dimension (D), capacity dimension (D0), entropy dimension (D1), and correlation dimension (D2) of trapped sediment particle size distribution. However, trapped sediment mass of three-month-old seedlings was only related to D, while that combining the data in both ages had significant correlations with D and D0. Our results suggest that fractal dimension of sediment particle size distribution can predict sediment mass trapped by plants. Such knowledge may help maximize sediment trapping through appropriate species selection and provide useful information for slope erosion control.

Background: Saline soils severely affect plant growth. Associations between endophytes and plants are known to significantly alter plant metabolism. This study reports the effects of a fungal endophyte species (Botryosphaeria ramosa ssp.) on osmoregulation, antioxidant enzymes, and the regulation of endogenous plant hormones in Casuarina equisetifolia under NaCl stress. C. equisetifolia plants, with and without B. ramosa ssp. colonization, were subjected to different levels of NaCl stress (0%, 5%, 10%, and 15%) for different amounts of time (0 d, 20 d, 40 d, and 60 d). Results: Antioxidant enzymes, phytohormones, and nutritive elements in the leaves and roots were determined. The results showed that colonization of the roots by B. ramosa ssp. improved the growth rate and dry weight of salt-stressed plants. Moreover, B. ramosa ssp. colonization increased the activities of superoxide dismutase, catalase, and peroxide but decreased the hydrogen peroxide content in the branches of C. equisetifolia under salt stress. Meanwhile, compared with non-colonized plants, endophyte colonization reduced the abscisic acid and proline contents but increased the contents of auxin, zeatin, and gibberellins. Importantly, the nutrient elements in the roots and branches of colonized plants were significantly different from those in the roots and branches of non-colonized plants under saline conditions. Conclusions: The results of this study showed that B. ramosa ssp. colonization can enhance the salt tolerance of C. equisetifolia. by improving the antioxidant enzyme content, regulating the phytohormones, and adjusting proline accumulation under NaCl stress.

It is critical to understand how forests regenerate after the exclusion of human induced disturbances because the regenerating species drive the renewal of resources and ecosystems, which in turn support human beings locally and globally. This study of forest regeneration was conducted in the tropical coastal forest ecosystems of Tanzania at Uzigua Forest Reserve (24,730 ha) in the Pwani Region. We collected data from adult trees in 47 sampling plots (25 × 25 m) randomly established in closed forest sites (control) and in sites disturbed by farming and livestock grazing. Sapling and seedling data were collected and analyzed in 2 × 2 m nested subplots. Plots in the closed forest had higher mean basal area and volume for adult trees than those in sites disturbed by farming and livestock grazing. Plots in sites disturbed by farming had the highest Shannon–Wiener index for seedlings and saplings, followed by closed forest and livestock grazed sites. Closed plots and farmed plots had higher Simpson’s index for seedlings and saplings than in grazed sites. Plots in farmed and livestock-grazed sites had a higher Simpson index for adult trees than in closed sites. Equitability of seedlings and saplings was highest in closed forest sites, followed by farmed and livestock grazed sites. Plots disturbed by farming had higher equitability for adult trees than in livestock-grazed and closed sites. Moreover, plots disturbed by farming and grazing had a higher importance value index for seedlings than in closed sites. Plots in closed forests had higher sapling importance values than in farmed and grazed sites. Again, plots in closed forest had a higher importance value for adult trees than in farmed and grazed sites. The differences in tree species subcategories of regeneration across land-use indicates that farming and livestock grazing disturbances create heterogeneous microhabitats, which positively or negatively affects regeneration capacity of species after exclusion.

Understanding about land cover and land use (LCLU) changes, as well as the associated impacts on ecosystem service values (ESV) is extremely important in the management of coastal ecosystems globally. Thus, this study assessed temporal LCLU changes, the underlying socioeconomic drivers and dynamics of ESV in the coastal zone of Tanzania. The LCLU data for 2000 and 2010 were from the Globe Land 30 mapping products at 30-meter spatial resolution developed by National Geomatics Center of China, while 2016 images were produced from Landsat 8. Classification of images was done from Landsat TM/ETM+ for 2000, 2010, and 2016 years complemented with MODIS and Normalized Difference Vegetation Index time series, and Chinese HJ imagery. LCLU categories and ecosystem service coefficients were used to compute ESV on each LCLU categories. Between 2000 and 2016, farmland, shrub land, waterbody, and artificial surface expanded while forest, grazing land, and wetlands declined. The ESV increased on farmland, shrub land, and waterbody, while the decline was found on forest, grazing land, and wetlands. The ESV and the total population ratios declined from $80.4, 63.8, and $46.0 million in 2000, 2010, and 2016, respectively. Perfect positive correlation was on LCLU change and ESV, population and households in crop farming, livestock keeping, and bioenergy use. Population pressure and socioeconomic activities have amplified the degradation of the coastal ecosystems. If not abetted, there is a danger of further impairments on these ecosystems. We advise to regulate population and socioeconomic activities to avoid more negative impacts of coastal LCLU change.

China is a globally important ecosystem that is undergoing rapid development and land use/cover change (LUCC). The role of road networks in the LUCC is becoming increasingly important. Much of the upgrading in road networks is propelled by economy and population growth. However, the relationships between the road networks and the social-economic factors are poorly understood by using the ordinary least squares (OLS) regression, which assumes that the estimated beta value holds the same everywhere within a given study area. To determine whether there is spatial variation in the relationship between the road networks and the social-economic drivers in a given region, we employed a local model, geographically weighted regression (GWR), that provides a regression coefficient (beta) for each sample location within the study area. Taking Fujian Province, one of the most developed regions in China, as a case, this paper firstly employed an Exploratory Spatial Data Analysis (ESDA) to identify the spatial patterns of the road networks at the different sizes of sampling units. We found that the spatial distribution of road networks had an obvious tendency toward the geographical dependency, with High-High clusters seated in the eastern coastal areas and Low-Low clusters distributed dispersedly in the study area. The spatial patterns of the road networks had highly consistency in the different sizes of sample units. Then, the GWR model confirmed that the relationships between the road networks and the socioeconomic factors varied by locations, with multiple relationships (both synergy and tradeoff) between them coexisting in the study region. These relationships were also visualized by sign and magnitude of the estimated coefficients of GWR for each sampling unit, which allow us to compare the different effects of the dependent variables on the road networks across locations. We also found that the variable of gross domestic product density (GDPD) is a preferred indicator over the variable of population density (PD) to analyze the associations with the road networks. Thus, this study provided useful information to develop differentiated strategies for road development at the finer level by using the more nuanced GWR models.

Aim: Estimation of carbon in the forests located in the coast of tropics is needed to support conservation and forest monitoring strategies. This study aimed at quantifying carbon stocks in the regenerating tree species of intact forest (IFS), disturbed by agriculture (ADS) and by livestock grazing sites (LDS) to understand the importance of coastal trees in carbon stocking as part of mitigating climate change impacts. Methodology: Thirty-three independent measurements of tree carbon stocks were carried out on 33 tree families found in the coastal zone of Tanzania. The vegetation was inventoried by means of a floristic survey of the woody component across intact, crop agriculture and livestock disturbed land use sites. The biomass was then estimated by employing the existing allometric equations for tropical forests. Thereafter, the above ground stored carbon was quantified on the sampled tree species found in each land uses. Results: The results showed that there were significant variations (p ≤ .05) of carbon stock values across species and land uses. The average carbon (Kg/ha) stored in the regenerated adult trees was 1200 in IFS, 600 in ADS, 400 in LDS. Saplings had 0.43 in LDS, 0.07 in ADS and 0.01 in IFS. Indeed, seedlings had the average of 0.41 in IFS, 0.22 in ADS and 0.05 in LDS. Conclusion: These findings show that crop-agriculture highly affects the regeneration potential of trees, biomass accumulation and carbon stock than livestock grazing. To restore carbon storage potential of coastal tropical forests, crop-agriculture must be discouraged, while livestock grazing can be integrated in forest management. Indeed, further studies are required to gauge the integration levels of any anthropogenic activities, so that the natural capacity of coastal tropical forests to regenerate and stock carbon is not comprised further.

Tree species-abundance in forests is a function of geographical area and climate, although it is not clear whether such relationships apply to mass islands. We examined the spatial pattern of tree species in mass islands along the coast of Zhejiang, East China Sea using the Preston model, to identify the relationships between tree communities and climatic conditions. The results show that: (1) the biogeographical distribution of tree species-abundance conformes to Preston’s log-normal pattern, and is in accordance with the findings in both tropical rainforests and estuarine forests; (2) the climatic factors related to tree communities in mass islands are similar to that of the subtropical zone, including the major species of evergreen needle-leaf, broad-leaf and deciduous broad-leaf forests. We conclude that the Preston model can be applied to the trees of mass islands and thus facilitate the systematic ecological researches of vegetation species’ composition in subtropical zone.

The mid-subtropical forest is one of the biggest sections of subtropical forest in China and plays a vital role in mitigating climate change by sequestering carbon. Studies have examined carbon storage density (CSD) distribution in temperate forests. However, our knowledge of CSD in subtropical forests is limited. In this study, Jiangle County was selected as a study case to explore geographic variation in CSD. A spatial heterogeneity analysis by semi-variogram revealed that CSD varied at less than the mesoscale (approximately 2000–3000 m). CSD distribution mapped using Kriging regression revealed an increasing trend in CSD from west to east of the study area. Global spatial autocorrelation analysis indicated that CSD was clustered at the village level (at 5% significance). Some areas with local spatial autocorrelation were detected by Anselin Local Moran’s I and Getis-Ord G*. A geographically weighted regression model showed different impacts on the different areas for each determinant. Generally, diameter at breast height, tree height, and stand density had positive correlation with CSD in Jiangle County, but varied substantially in magnitude by location. In contrast, coefficients of elevation and slope ranged from negative to positive. Based on these results, we propose certain measures to increase forest carbon storage, including increasing forested area, improving the quality of the current forests, and promoting reasonable forest management decisions and harvesting strategies. The established CSD model emphasizes the important role of mid-subtropical forest in carbon sequestration and provides useful information for quantifying mid-subtropical forest carbon storage.

Salt water intrusion is a challenge on production of human staple foods Zea mays and Oryza sativa in the changing climate, along the global coastal zones. Information on how salinity affects these crops is essential in developing scientific mitigations for sustainable food production. This study was conducted to investigate salt water intrusion and its impacts on Zea mays and Oryza sativa production in Bagamoyo District, Tanzania. Soil and water samples were collected along 14 km of Wami River for determination of NaCl and pH. Direct observations, surveys and questionnaire protocols were used to collect socio-economic data. Along 14 km, soil pH average was 6.5 (acidic) while that of water was 8 (basic). Salinity was high within 5 km and then declined towards 14 km away. Zea mays and Oryza sativa declined from averages of 18 to 8bags/acre/crop season. The impacts of salinity were clear on farms within 5 km from the Ocean than at 14 km. Salt intrusion is associated with climate change along the Tanzania coastal zone. Agriculturists, environmentalists and policy makers must work jointly to mitigate SWI impacts in Changing Climate. These efforts will help to improve crop production and ensure food security and income of the people along the coastal zones.

China’s 2008 8.0 Ms Wenchuan earthquake and subsequent secondary geo-hazards caused widespread damage to vegetation-soil system in northwest China. In order to evaluate changes in soil quality status after damage, we established four treatments in the earthquake-affected area, including disturbed and treated sites in a dry hot climate (D-t), undisturbed sites in a dry hot climate (D-ud), disturbed and treated sites in a subtropical humid monsoon climate (S-t), and undisturbed sites in a subtropical humid monsoon climate (S-ud). Forty-eight soil samples were collected and analyzed for 27 soil physical, chemical, and biological properties. Principal components analysis (PCA) was conducted with 26 variables in significant differences except total potassium among D-t, D-ud, S-t, and S-ud. A minimum data set of soil indicators was established with available potassium (AK), K + , total salt content (TSC), and total phosphorus (TP) based on PCA results. Using the Integrated Quality Index (IQI) equation, we calculated the soil quality index (SQI). S-ud, S-t, D-ud, and D-t had mean SQI scores of 0.566, 0.275, 0.537, and 0.374, respectively. Our results showed that undisturbed sites had better soil quality compared to disturbed and treated sites based on their superior physical indicators, superior nutrient conditions, and higher microbial carbon source metabolic diversity, especially in the subtropical humid monsoon climate with frequent rainfall. The SQI reflects the variations observed in earthquake-affected area and may be considered as a suitable technique for detecting changes in soils. Our results will also supply the fundamental data for evaluating the effects, design, and implementation of restoration programs.

Wind, salt spray, and the proximity to the coastline significantly caused the variation of tree shape and dry mass density of Casuarina equisetifolia L. planted in coastal areas. Despite negative effects of exotic plants, they play an important role in the erosion control and the accumulation of wind-borne deposits in coastal areas. Identifying the adaptive strategies of exotic species and predicting their ability for stress adaption are of great interest to improve the management and regeneration of coastwise protective forests. We studied Casuarina equisetifolia L., an introduced tree planted successfully for dampening wind speed and preventing coastal soil erosion in coastal regions of southern China, 450–1400 m from the coastline in Taiwan Strait. Morphological and functional traits were measured on the windward and leeward sides of each of 48 trees of identical age and diameter. Coastal stress was measured by wind speed and salt spray. Traits were summarized using the Principal Component Analysis (PCA), and PC scores were related to coastal stress and to other environmental effects. Morphological traits were summarized as PCs describing tree shape, branch supporting capacity, and branching pattern. Coastal stress significantly influenced tree shape, but not branch supporting capacity and branching pattern. Tree shape was also affected by other environmental factors. Functional traits were summarized by PCs describing dry mass density, dry matter content, and water balance, but only dry mass density was influenced by coastal stress or other environmental factors. Our study indicated that C. equisetifolia adapts to coastal stress by altering its tree shape and dry mass density. Our results provide useful information for the selection of adequate species for the erosion control and management of coastal areas.

Aluminum toxicity is common in subtropical acidic soils, and the effect of Al stress on Aleurites montana is unknown. This study determined the growth and Al and macronutrient contents (C, N, P, K, Ca, and Mg) in leaves and roots of 1-year-old A. montana seedings to reveal the effects of Al stress on growth and elements of A. montana seedings and the difference of growth and content of elements in potted seedlings and hydroponic seedlings under Al addition. The content of Al in the leaves of potted A. montana seedlings was greater than 1000 mg kg−1 under Al stress, so it can be judged that A. montana is likely an Al accumulator and has a high Al tolerance in potted soil. The changes of macronutrient contents in the seedlings varied with Al concentration. For potted seedlings, Al stress had a significant effect on Mg and K contents in roots and Mg and C contents in leaves, but it had no effect on other macronutrients, such as N, P and Ca. For hydroponic seedlings, Al content in roots and N, P, and K contents in roots and leaves increased significantly, and C and Ca contents in roots decreased significantly when the Al concentration exceeded 0.290 mmol L−1. The Al stress affected the distribution and transportation of macronutrients between roots and leaves. The Al and K contents in the roots were higher than those in leaves in both cultivation methods, while the C, N, and Ca contents were smaller than those in leaves. The transportation of N, P and Ca from root to leaf in potted seedlings changed with the increase of Al concentration. There were major differences in the growth and the absorption and transportation of elements between potted and hydroponic seedlings under Al stress. In this study, Al promoted or had no significant effect on the growth of potted seedlings, while the growth of hydroponic seedlings was significantly inhibited when the Al concentration was relatively high. Moreover, the effect of Al concentration on Al and macronutrients of potted seedlings was less than that of hydroponic seedlings. Therefore, the effects of the primary environment should be considered in future stress experiments. This study revealed the effect of Al concentration on A. montana seedlings from the perspective of growth and nutrition, which are crucial in ecological restoration function of mixed tree species in acid rain area. Comparison of the effects of Al concentration on A. montana seedlings under two cultivation methods provides new perspectives for future stress test research.

Using knowledge mapping tools (CiteSpace), we conducted the visualization analysis on both of international and domestic literatures in relation to ecological assets/values from the Web of Science (WoS) databases and China National Knowledge Infrastructure (CNKI) databases. By combination of the statistical data and visualization mapping, we studied on the research relationship networks and status for the co-authors' institutions, co-authors, co-citation literatures and co-occurring keywords of ecological assets/values based on the sample data from literatures. In the aspects of research on ecological values, our results showed that: (i) main countries of researches on ecological values were the United States, Australia, Canada and China in order, especially the US had the most plenty of literatures in relation to ecological values, and at the same time, literatures from China in this field are in the upper level; (ii) the hotspots of researches on ecological values from the global literatures covered various fields including biodiversity, species richness, ecosystem services, landscape, climate change and dynamic simulation; (iii) as a result of the multidisciplinary integration, the hotspots of researches on ecological values emerge endlessly, so that many high yielding authors and relevant international institutions constantly expanded the research scopes and fields, which promoted the combination of theories and made the significant contribution to themselves; (iv) the mass domestic researches on ecological values began in 1992. The number of posting paper increased obviously and the scopes in relation to ecological value expanded gradually, particularly involved with ecology, economy, even legal and ideology, which illustrated that concepts of “ecological values” had not been only confined to the researches on the traditional science, but also been widely used in many fields of humanity and social science. In the aspect of research on ecological assets, our results showed that: (i) domestic researches on ecological assets had many points in common with ecological values research. In fact, driven from ecological values, researches on ecological assets became gradually characteristic, such as assessment of forest ecological asset, ecological industry and fair value measurement of ecological assets, all of which contained lots of considerable consequences; (ii) the Chinese Academy of Sciences was in the dominant position of domestic research on ecological assets. Other colleges and universities like Beijing Normal University and Nanjing Forestry University were also effective and productive in this field. Their achievements were already improving Chinese academic level; (iii) domestic research teams also changed from different discipline backgrounds to enrich the research scopes of ecological assets. Based on analysis of typical literatures from our results, in the similarity and difference of the concept of “ecological asset” between foreign and domestic literatures, we summarized key points that we should pay attention to: (i) ecological assets included natural resources and ecosystem services; (ii) ecological assets consisted of tangible and intangible parts; (iii) ecological assets were of profitability and public welfare at the same time. Finally, we elucidated that future trend of research on ecological assets would pay more attention to the internal mechanism of changes of ecological assets, determination of the bearing capacity of the ecological environment by such changes, and discovery of accumulation of ecological assets for a stable and sustainable development of the ecosystem, and for harmony between humans and environment.

Ecosystem services are strongly influenced by the landscape configuration of natural and human systems. So they are heterogeneous across landscapes. However lack of the knowledge of spatial variations of ecosystem services constrains the effective management and conservation of ecosystems. We presented a spatially explicit and quantitative assessment of the geographic variations in ecosystem services for the Fuzhou City in 2009 using exploratory spatial data analysis (ESDA) and semivariance analysis. Results confirmed a significant and positive spatial autocorrelation, and revealed several hot-spots and cold-spots for the spatial distribution of ecosystem service intensity (ESI) in the study area. Also the trend surface analysis indicated that the level of ESI tended to be reduced gradually from north to south and from west to east, with a trough in the urban central area, which was quite in accordance with land-use structure. A more precise cluster map was then developed using the range of lag distance, deriving from semivariance analysis, as neighborhood size instead of default value in the software of ESRI ArcGIS 10.0, and geographical clusters where population growth and land-use pressure varied significantly and positively with ESI across the city were also created by geographically weighted regression (GWR). This study has good policy implications applicable to prioritize areas for conservation or construction, and design ecological corridor to improve ecosystem service delivery to benefiting areas.

This study examined the hypotheses that soil microbial community composition and catabolic activity would significantly degenerated by consecutive monoculture in Chinese fir plantations. The phospholipid fatty acids (PLFA) and community level physiological profiles (CLPP) methods were used to assess the variations of soil microbial community among the first rotation Chinese fir plantation (FCP), the second rotation plantation (SCP) and the third rotation plantation (TCP). The total content of PLFA biomarkers was highest in FCP, followed by SCP, and TCP was the least detected. Conversely, the fungi/bacteria ratio significantly increased in the SCP and TCP soils. The average well-color development (AWCD) values significantly decreased (FCP > SCP > TCP). However, the sum of AWCD values of amino acids, carboxylic acids and phenolic compounds were higher significantly in the SCP and TCP soils than FCP soils, suggesting that the microflora feeding on acids gradually became predominant in the continuous monoculture plantation soils. Soil C/N ratio was one of the most important factors to soil microbial diversity. Both the PLFA and CLPP results illustrated the long-term pure plantation pattern exacerbated the microecological imbalance in the rhizospheric soils of Chinese fir, and markedly decreased the soil microbial community diversity and metabolic activity.

The MS 8.0Wenchuan Earthquake in 2008 caused huge damage to land cover in the northwest of China's Sichuan province. In order to determine the nutrient loss and short term characteristics of change in soil chemical properties, we established an experiment with three treatments ('undestroyed', 'destroyed and treated', and 'destroyed and untreated'), two climate types (semi-arid hot climate and subtropical monsoon climate), and three slope positions (upslope, mid-slope, and bottom-slope) in 2011. Ten soil properties-including pH, organic carbon, total nitrogen, total phosphorus, total potassium, Ca2+, Mg2+, alkaline hydrolysable nitrogen, available phosphorus, and available potassium-were measured in surface soil samples in December 2014. Analyses were performed to compare the characteristics of 3-year change in soil chemical properties in two climate zones. This study revealed that soil organic carbon, total nitrogen, Ca2+ content, alkaline hydrolysable nitrogen, available phosphorus, and available potassium were significantly higher in subtropical monsoon climate zones than in semi-arid hot climate zones. However, subtropical monsoon climate zones had a higher decrease in soil organic carbon, total nitrogen, total phosphorus, total potassium, and alkaline hydrolysable nitrogen in 'destroyed and untreated' sites than in semi-arid hot climate zones. Most soil chemical properties exhibited significant interactions, indicating that they may degrade or develop concomitantly. 'Destroyed and treated' sites in both climate types had lower C:P and N:P ratios than 'destroyed and untreated' sites. Principal component analysis (PCA) showed that the first, second, and third principal components explained 76.53% of the variation and might be interpreted as structural integrity, nutrient supply availability, and efficiency of soil; the difference of soil parent material; as well as weathering and leaching effects. Our study indicated that the characteristics of short term change in soil properties were affected by climate types and treatments, but not slope positions. Our results provide useful information for the selection of restoration countermeasures in different climate types to facilitate ecological restoration and reconstruction strategies in earthquake-affected areas.

Rapid human-driven conversion of global forest cover is contributing to the loss of habitat, biodiversity, and climate change. Even in a relatively short time interval and a small local region with relatively homogeneous biophysical interference, forest cover may be changed considerably by human disturbances. To better understand human influences on the pattern of forest cover change (FCC), we investigated the factors of FCC from 2007 to 2012 by combining the broad socio-economic information at the census block group level with the site-specific information measured at the pixel level. Taking the upstream area of the Minjiang River, China, as a case study, the result indicated that the major forest cover classes had a high rate of persistence in area size during the study period, while conversions among forest covers and into non-forest land occurred frequently, accounting for 5.4% of the landscape. The change of mixed forest was among the greatest one, decreasing sharply from 24.0% to 21.6% of the entire landscape, which converted predominantly into coniferous forest from 2007 to 2012. Additionally, 90.0% of the net gain to non-forest land was largely supplied by coniferous forest and mixed forest. The findings corroborate that human-driven conversions of forest covers have deleterious effects on biodiversity conservation in the upstream area of the Minjiang River. Furthermore, a binary logistic regression model was used to observe the biophysical/socio-economic drivers of FCC. We identified a FCC pattern during the period of study that was associated with collective- or enterprise-owned forests, low level of protection intensity forests, and the regions with high growth rates of fiscal revenue and far away from the city center. These results confirm that as a whole the relevant governments play an important role in the FCC in the region. This study is important for the relevant policy-makers and planners to better understand the underlying patterns and causes of this landscape change, to develop effective strategies for conserving biodiversity.

Declining vegetation coverage caused by serious soil erosion in dry-hot river valley of the Jinsha River has resulted in a vicious cycle of environmental deterioration and aggravated soil erosion. In order to identify the relationship between vegetation succession and transformation of soil erosion, the methods of "space replacing time" and Cs-137 technique have been used to analyze community structure of vegetation and distribution characteristics of Cs-137 contents in the slopes and vegetation units of five succession stages, which included native grassland, shrub, sapling forest, half-mature forest and near mature forest in Jiangjiagou gully, Dongchuan city, Yunnan province. We found, during the course of succession, the number of species in communities increased with vegetation development and succession, but the Cs-137 loss decreased with vegetation succession. Following the succession, near mature forest had the highest Cs-137 inventory and native grassland had the lowest Cs-137 inventory in both slopes and vegetation units. Principal component analysis showed that Cs-137 inventory was significantly positively correlated with average crown diameter of tree (ACDT), species number, tree coverage and average tree height. Average crown diameter of shrub (ACDS) and average shrub height were also positively related to Cs-137 inventory but to a lesser extent. Based on the results of our study, we illustrated the improvement of soil erosion control through soil conservation and water regulation with vegetation succession. Consequently, the results suggest that community features significantly affect soil erosion, through which we can evaluate and predict the soil erosion intensity of different vegetation. (C) 2013 Elsevier B.V. All rights reserved.

In this paper, substitution cost methods and prevention cost methods were used to estimate the influence of construction land on the ecosystem service value (ESV). Then, the total ESV was adjusted by the influence. The results showed that the ESV of Fuzhou City dropped from 105, 061.53 million Yuan in 1986 to 103, 916.53 million Yuan in 2006, mainly due to the degradation of cropland and water body and the increase of construction land. Water supply and waste treatment were the two largest ecosystem services, contributing approximately 35% of the total ecosystem service in both years. On the basis of land-use transition matrix, the compartment theory was applied to simulating landuse spatial pattern dynamics under different artificial intervention scenarios. The results showed that if we maintain or increase the existing intensity of interference, the total ESV of Fuzhou City will decrease by 58.13 million Yuan per year or 122.99 million Yuan per year, respectively; if we reduce the existing intensity of interference, the total ESV will increase by 52.38 million Yuan per year. In addition, the total ESV will decrease by 4.84 million Yuan for each 10% increase in the speed of the urbanisation process. We can conclude that the disordered expansion of construction lands and imbalance of ecological lands are main problems impeding the harmonious urban development. Given the similar social environment across the Chinese mainland, the findings from our study have important implications for the sustainable development of other rising cities in China and beyond.

The objective of this study was to understand the effects of forest gap and variations in different seasons, gap size, locations and diurnal variations on forest microclimate and soil water content. Spatial and temporal distribution features of air temperature (TA), soil temperature (TS), relative humidity (h) and soil water content (Ψ) were measured in Castanopsis kawakamii natural forest gaps created by a severe typhoon or fallen dead trees. The results showed that: (1) the variations of TA, h, and TS in four seasons were extremely significant. The variations of Ψ in four seasons were extremely significant except for those between spring and summer. (2) The diurnal variations of TA and TS were expressed with a single peak curve. The diurnal variations of h and Ψ presented a high-low-high trend. (3) The variations of TA, h, and TS were extremely significant among the large, medium and small gaps in C. kawakamii natural forest. Medium gaps had the highest TA and the lowest h while small gaps were just contrary to medium gaps. The variations of Ψ were extremely significant for large, medium and small gaps except those between the medium and large gaps. (4) The TA, h, TS and Ψ were decreased from the gap center, canopy gap, expanded gap to understory. These results will help further our understanding of the abiotic and consequent biotic responses to gaps in the mid-subtropical broadleaved forests, which also provide a theoretical basis for the scientific management and population restoration of C. kawakamii natural forest.

In this study, the dynamics of monthly variation in litterfall and the amount of nutrients, i.e., organic C, N, P and K, in an Aleurites montana plantation were analyzed, based on a field study and experiments over one year. The results show that the litterfall mass of A. montana collected generally presents an ascending trend with maximum defoliation occurring in the autumn and winter (October–December), accounting for 75.67% of the total amount of annual litterfall. The sequence in the amount of nutrients in A. montana litter was as follows: organic C > N > K > P; their monthly amounts show various dynamic curves. Similar to the dynamics of the mass of monthly litterfall, the monthly returns of C, N, P and K generally show an ascending trend with their peak values all occurring in December. The mass of A. montana litterfall and the dynamics of its monthly nutrient return provide, to a certain degree, a scientific reference for planting and fertilizing A. montana.

The greenness (SPAD) of uneven-aged leaves of dominant species in the Castanopsis carlessi forest at different altitude gradients in Lingshishan National Forest Park, Fujian Province, China were measured by using portable chlorophyll meter SPAD-502. In addition, the correlation between SPAD value and the concentration of chlorophyll and foliar nitrogen was also investigated. Significant variations in SPAD values were found between the uneven-aged leaves of different dominant species and different altitude gradients. Regression analysis showed that SPAD value was significantly correlated with the concentration of chlorophyll and the content of foliar nitrogen, indicating that SPAD value could be indicators for foliar chlorophyll and nitrogen. It is suggested that SPAD meter is a useful tool for forest assessments in decision-making and operational nutrient management programs.

Studies on disclosing characteristics and endangered mechanisms of Castanopsis kawakamii population ecology have already become an urgent task of protecting C. kawakamii population. The establishment of the standard life table is one of an important work study on C. kawakamii population ecology, and determining individual ages of the plant is necessary for studying age structures and population dynamics of C. kawakamii . There are three main methods of determining individual age of forest population: (1) by annual ring of tree, (2) by individual growth phase, and (3) by DBH and height of tree. However, the three methods have their shortcomings, such as low precision, worse serviceability, high difficulty for operation and so on. In this paper, a new method for determining plant individual ages more accurately is presented on the basis of the method about “annual ring–time series”. Based on the stem analysis, the multidimensional time series model of diameter growth at breast height in C. kawakamii population was established by utilizing the analytical method of multidimensional time series: Y t = 1.325034 Y t −1 − 0.4711007 Y t −2 − 284.5648 U t + 569.4783 U t −1 − 284.8745 U t −2 , where Y t , Y t −1 , Y t −2 represent diameter growth in C. kawakamii population at t , t − 10 and t − 20 years respectively, and U t , U t −1 , U t −2 represent individual age in C. kawakamii population at t , t − 10 and t − 20 years respectively, the model coefficient correlation is 0.9994. Based on this model CAR(2), the total increment of individual DBH in C. kawakamii population are simulated and regressively verified at different ages. The mean simulating precision of this model was 98.84%, the maximum relative error was 2.56%, but the next was 2.47% and the minimum relative error was 0.07%, showing that this model was suitable for estimating breast-height diameter of C. kawakamii plant. Using the multidimensional time series model, diameter growth of C. kawakamii population for longer time series was estimated in order to gain data for establishing the relationship model of individual age, diameter growth and to increase its precision in determining individual age is by tree ring analysis. A combination method of determining individual age of C. kawakamii population by integrating annual ring data with its diameter using multidimensional time series model, which can improve precision of individual ages in C. kawakami , was produced: A = 9.966671944 + 1.146011591 D + 0.041059628 D 2 − 0.000211907 D 3 , where A and D represent individual age and diameter at breast height respectively in C. kawakamii population, the model coefficient correlation is 0.9998. The combination model, which shows that the regression relationship is significant and the model can exactly predict the individual age of population, is a valuable tool for determining individual ages in endangered plants.

This review describes the characteristics and hot spots of wetland research, including biodiversity protection of wetland, management and restoration of wetland, function and process of wetland, and the theories, methods and scales of landscape ecology. Moreover, some deficits of landscape ecology theory and method were discussed, and the application of landscape ecology to research on wetlands was reviewed specially, involving in the application of landscape structure principle, landscape pattern, and scale and hierarchy theory. In conclusion, landscape ecology plays an enlightening and guiding function on the comprehensive research of wetlands at multi-scales.