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    Plant and Animal Ecology
  • Plant and Animal Ecology
    QIN Yong, FU Gang, SHEN Zhenxi, ZHONG Zhiming
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    There has been an obvious diurnal asymmetrical warming effect as a result of the overall climate warming in the Tibetan Plateau. To reduce the uncertainty caused by the diurnal asymmetrical warming effect on future food security predictions in the Tibetan Plateau, this study used winter highland barley (var. Dongqing No. 1) for the experimental materials, and the FATI (Free Air Temperature Increase) field open heating system to carry out a simulated diurnal asymmetrical warming experiment (AW: All-day warming, DW: Daytime warming, NW: Nighttime warming, CK: Control) for two growing seasons (2018-2019 and 2019-2020) at the Lhasa Agroecosystem Research Station. The growth characteristics and yield of Tibetan winter highland barley were investigated in this study. Compared to the control, all the AW, DW and NW treatments had significant effects on the phenological period of winter highland barley, with the advancement of the phenological phase and shortening of the whole growth period. The degree of influence was AW>NW>DW, and all the AW, DW and NW treatments shortened the interval from sowing to heading of winter highland barley and increased the interval from heading to maturity. The effect on the phenological phase was the most obvious for AW and reached a statistically significant level (P<0.05). During the generative growth phase, the biomass above-ground and plant height of winter highland barley had an increasing tendency under the different warming conditions. In the late growth period, the biomass above-ground and plant height of the NW treatment were significantly higher than those of the other treatments. In addition, the warming caused a decrease in the dry matter distribution proportions of leaves and stems at the mature stage, and an increase in the distribution ratios of roots and spikes; and the AW, NW and DW treatments increased grain yields by 16.4%, 24.6% and 9.5%, respectively, on average in the two years. The increasing effect on grain yields of the NW treatment reached a significant level compared with the control in 2019-2020 (t=-2.541, P=0.026). In terms of yield composition, the effective spike number and 1000-grain weight tended to increase. The grain number per spike tended to increase, except for the AW treatment, while panicle length and seed setting rate tended to decrease, except for the NW treatment. Therefore, the effects of different simulated diurnal asymmetrical warming treatments on the growth characteristics and yield of winter highland barley were variable in the Tibetan Plateau.

  • Plant and Animal Ecology
    ZHANG Zhiyong, FAN Baomin, SONG Chao, ZHANG Xiaoxian, ZHAO Qingwen, YE Bing
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    Root system architecture (RSA) refers to the spatial distribution and extended morphology of plant root systems in soil. RSA not only determines the ability of plants to obtain water and nutrients but also affects other ecological functions. Hence, it plays a dominant role in the overall health of plants. The study of RSA can provide insight into plant absorption of water and fertilizers, the relationship between above- and belowground plant parts, and the physiological health and ecological functions of plants. Therefore, this paper summarizes research on the morphology, functionality, plasticity and research methods of RSA. We first review the basic structure, physiology, and ecological functions of root systems. Then the soil factors that shape RSA—including soil moisture, nutrients, temperature, aeration, and others—are summarized. After that, research methods for studying RSA are described in detail, including harvesting, two-dimensional morphological observation, and three-dimensional image reconstruction. Finally, future research developments and innovations are discussed to provide a theoretical basis for further investigations in this field.

  • Plant and Animal Ecology
    GUAN Peng, ZHENG Yili
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    Research on forest phenology is an important parameter related to climate and environmental changes. An optical camera was used as a near-earth remote sensing satellite device to obtain forest images, and the data of Green excess index (GEI) in the images were calculated, which was fitted with the seasonal variation curve of GEI data by double Logistic method and normalization method. LSTM and GRU deep learning models were introduced to train and test the GEI data. Moreover, the rationality and performance evaluation of the deep learning model were verified, and finally the model predicted the trend of GEI data in the next 60 days. Results showed: In the aspects of forest phenology training and prediction, GRU and LSTM models were verified by histograms and autocorrelation graphs, indicating that the distribution of predicted data was consistent with the trend of real data, LSTM and GRU model data were feasible and the model was stable. The differences of MSE, RMSE, MAE and MAPE between LSTM model and GRU model were 0.0014, 0.013, 0.008 and 5.26%, respectively. GRU had higher performance than LSTM. The prediction of LSTM and GRU models about GEI data for the next 60 days both showed a trend chart consistent with the change trend of GEI data in the first half of the year. GRU and LSTM were used to predict GEI data by deep learning model, and the response of LSTM and GRU deep learning models in forest phenology prediction was realized, and the performance of GRU was better than that of LSTM model. It could further reveal the growth and climate change of forest phenology in the future, and provide a theoretical basis for the application of forest phenology prediction.

  • Plant and Animal Ecology
    Wakshum SHIFERAW, Sebsebe DEMISSEW, Tamrat BEKELE, Ermias AYNEKULU
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    Investigation of the invasion of Prosopis juliflora and its effects on indigenous plant species are important for the control of the species. The study aimed to assess: (1) the effects of Prosopis juliflora invasion on the diversity of plant species in Awash Fentale and Amibara Woredas; (2) the effects of Prosopis juliflora invasion on the regeneration potential of native woody species. Sample collection was performed in habitats of Prosopis juliflora thicket, Prosopis juliflora mixed with native species stands, non-invaded woodlands, and open grazing lands. The vegetation was stratified into invasion levels of Prosopis juliflora and then a random sampling technique for data collection. Among species of plants, the highest proportion of species, 75 (47.8%), was recorded under non-invaded woodlands, but the lowest proportion of species, 22 (14%), was recorded under open grazing lands. The invasion of Prosopis juliflora reduced the Shannon diversity index. The mean values of the Shannon diversity index and species richness under Prosopis juliflora mixed with native species (H′=2.22, R=14) and non-invaded woodlands (H′=2.23, R=13) were significantly higher than Prosopis juliflora thicket (H′=1.96, R=12) and open grazing lands (H′=1.84, R=10). The highest total density (358 stems ha?1) of seedlings was recorded under Prosopis juliflora mixed with native species. But, the lowest total density (153 stems ha?1) of seedlings was recorded under Prosopis juliflora thickets. Moreover, 102 trees ha?1 native woody species were recorded under Prosopis juliflora thicket, but 1252 trees ha?1 native species were recorded under non-invaded woodlands. If the invasion of Prosopis juliflora and its effects on native species diversity continue coupled with a drier climate, plant diversity of the Afar flora region will be highly affected and its ecosystem services will be under question. Thus, the participation of all stakeholders and multidisciplinary research approaches should be designed for the management of the species and rehabilitation of the rangelands in the region.

  • Plant and Animal Ecology
    Joseph P. LAMBERT, Johanna V. HARTMANN, SHI Kun, Philip RIORDAN
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    China’s Qinghai-Tibetan Plateau (QTP) is an important area for bird conservation, with many endemic and Threatened species. Colonial burrowing mammals play an important role in structuring bird communities in arid grasslands around the world. On the QTP, the plateau pika Ocho tona curzoniae builds colonies which provide a dense source of resources for many bird species. However, pikas are regarded as a pest by local pastoralists, and they are the target of a population reduction campaign which could have a significant impact on the bird communities. We surveyed bird communities at Gansu Yanchiwan National Nature Reserve to investigate the differences in community structure between sites with pika colonies (on colony) and sites without them (off colony), and between pika colonies which had been poisoned and those which had not. Using non-metric multidimensional scaling (NMDS) combined with permutational multivariate analysis of variance (PERMANOVA) and Wilcoxon rank-sum tests, we found that there was no significant difference in bird community composition or abundance between the poisoned and untreated colonies. However, there was a very large and statistically significant difference in bird community structures between on- and off-colony sites. Only horned lark Eremophila alpestris was consistently observed at sites without pika colonies, while ten bird species were observed on colonies. Six species were significantly more abundant on colony than off. While we could not claim that the poisoning campaign at Yanchiwan is altering bird communities, the presence of pika colonies seems to be an indispensable resource for the resident birds.

  • Soil Ecosystem
  • Soil Ecosystem
    LIU Ruixuan, YAO Yuan, ZHANG Sheng
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    As terrestrial ecosystem carbon (C) sinks, plantation ecosystems play essential roles in species diversity protection, resource supply and climate change. Artificial afforestation is of great important in improving the ecological condition, economic development and production in Tibet. Forests can improve soil property changes, yet the understanding of how plantations influence soil C and nutrient conditions in Tibet is still insufficient. This review combines with previous studies to explore the characteristics of soil nutrients, involving nitrogen (N) and phosphorus (P) on Tibetan poplar plantations. Generally, plantations have better abilities in improving the soil C and N cycles, and enhancing the soil stability. In this review, we further analyze the factors, including the modality of land-use, afforested period, tree species, climate factors and soil properties, which may affect the soil C and nutrients. (1) The patterns of land-use affect the accumulation of soil organic matter, thus influence the accumulation of soil C and nutrients; (2) Soil C and N increase with the years of artificial forests, while soil P is on the contrary; (3) The effects of different tree species on soil C and nutrients vary widely; (4) In terms of climate, the C sink of Tibetan plantation soil is most likely to be affected by precipitation, while the nutrient is more likely to be influenced by temperature; (5) Among soil properties, the most related factor to C is soil texture. Furthermore, our review pointed out that future research on soil ecological functions should be focused on soil microbes on Tibet plantation. At the end, we concluded three major challenges for the future research. Therefore, this review contributes to a better understand the effects of plantation on soil C and nutrients on the Tibetan Plateau.

  • Soil Ecosystem
    CHEN Yi, CAI Haisheng
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    Relying on the advantages of selenium-rich soil resources, the development of special selenium-rich agricultural industry is an effective measure to implement the rural revitalization strategy. This paper took Yuanzhou district as the research area, based on ecological niche theory, creatively determines the dominant and limiting factors of selenium-rich soil resources development and utilization from three aspects of natural resources endowment, land use conditions and ecological protection, constructed the evaluation index system of selenium-rich soil resources development and utilization and ecological niche suitability index measurement model, and explored the suitability of regional selenium-rich soil resources development and utilization and zoning. The research results show that: (1) The area suitable for exploitation of selenium-rich soil resources in the study area is 174658.4 ha, accounting for 68.83% of the total area, mainly distributed around Yuan River and in the central, northern, northwestern and northeastern areas of the study area. (2) Based on the evaluation results of the suitability of selenium-rich soil resources development and utilization and the development of related agricultural industries, the study area was divided into four functional zones of selenium-rich industrial development: core zone, key zone, development zone and radiation zone. The core zone and key zone are suitable for building selenium-rich agricultural industry demonstration area and selenium-rich products breeding production base, and the development zone and radiation zone can vigorously develop selenium-rich modern agriculture and selenium-rich recreation tourism, which will accelerate the development trend of multi-level and diversified selenium-rich industry in study area.This study can provide scientific, reasonable and feasible ideas and methods for the development and utilization of selenium-rich soil resources and the planning and development of selenium-rich industries in similar areas.

  • Soil Ecosystem
    WANG Xie, HU Yang, GUO Haixia, ZHANG Jianhua, TANG Tian, ZENG Qiguo
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    Soil is the most important carbon pool of the mulberry plantation ecosystem, so understanding the characteristics of the soil carbon pool in mulberry plantations provides an important basis for the research of carbon sinks in economic forest ecosystems and farmland ecosystems. In order to explore the spatial differentiation pattern of the relationship between carbon and nitrogen in mulberry plantation soil, this study analyzed the organic carbon content and total nitrogen content of the surface soil layer (0-20 cm) and the subsurface soil layer (20-40 cm) of 475 mulberry plantations in five major regions of China, Southwest China (SWC), Central South China (CSC), East China (EC), North China (NC), and Northwest China (NWC). The research showed seven key aspects of this system. (1) The soil organic carbon of mulberry plantations was significantly different at the two soil depths. The average content of organic carbon in the surface layer of mulberry plantation soil was 10.71±7.01g kg?1, which was 37.13% higher than that of the subsurface layer. (2) The soil organic carbon of mulberry plantations had significant differences in spatial differentiation, which was manifested as SWC>CSC>EC>NC>NWC. (3) The total nitrogen content in mulberry plantation soil had significant responses to the region, the soil layer depth, and the interaction between the region and soil layer depth. Among the regions, NWC had no significant difference between the surface layer and subsurface layer of the soil. EC had the maximum difference in total nitrogen content, with the total nitrogen content in the surface soil layer being 56.68% higher than that of the subsurface soil layer. The total nitrogen contents of the surface soil layers in the SWC and NC were 34.27% and 20.79% higher than those of the respective subsurface soil layers. (4) The mulberry plantation soil C/N ratios had a significant response to regional differences, as NWC>SWC> EC>CSC>NC, but this ratio had no significant response to soil depth. (5) Soil pH had significant spatial differentiation in relation to soil organic carbon and total nitrogen content in mulberry plantations. NWC had no significant correlation between pH and organic carbon or total nitrogen content, while CSC had a significant positive correlation between pH and both soil organic carbon and total nitrogen content. Other regions showed significant negative correlations between pH and both organic carbon and total nitrogen content. (6) There was a significant negative correlation between the C/N ratio of the surface soil layer and pH in mulberry plantations, which was mainly contributed by SWC, while the other regions’ surface soil layers had no significant correlations between C/N ratio and pH. (7) There was no significant correlation between the C/N ratio and pH in the subsurface soil layer in mulberry plantations. These results reveal that in either the research on mulberry plantation carbon pools or the innovation of green and low-carbon planting technology in mulberry plantations, the spatial differentiation characteristics of soil must be considered. Furthermore, the spatial differentiation of soil organic carbon can be used as the basic foundation for the planning and design of mulberry afforestation or ecological restoration projects.

  • Agriculture and Landscape Ecology
  • Agriculture and Landscape Ecology
    JIANG Difei, ZHENG Guanghui, LUAN Yongfei
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    Industrial prosperity is the foundation of rural revitalization. Taking the 552 agricultural industry demonstration towns (AIDTs) as the research object, this paper explores the spatial layout and influence mechanism of AIDTs in China. The research is of great significance to the layout of China’s agricultural industry and the revitalization of the rural agricultural industry. This paper adopts the ArcGIS 10.3 spatial analysis method to reveal the spatial distribution characteristics, density characteristics, spatial complexity, and spatial correlation of AIDTs in China. (1) The spatial distribution of AIDTs tends to be condensed distribution with remarkable spatial differentiation. (2) The kernel density of China’s AIDTs is characterized by multiple independent mononuclear centers, secondary centered bands, and sporadic distribution. (3) The AIDTs system is characterized by scaleless areas, significant fractal features, and complexity of spatial structure. (4) The AIDTs belong to positive spatial correlation present different patterns of cold and hot spots with the more concentrated spatial distribution. The research indicates that the spatial distribution pattern of China’s AIDTs is highly consistent with the distribution of major grain-producing areas. It is mainly determined by factors such as good natural conditions, convenient water resources, and good regional advantages and continuously implemented agricultural industry reform. With the “three changes” reform (i.e. change resources into assets, funds into shares, and farmers into shareholders) proposed by Liupanshui City in Guizhou Province in March 2015 as a strategy, take the agricultural industry scale development model and adheres to the guidance of the agricultural industry to contribute to rural revitalization. The research results are of essential guiding significance for China’s agricultural industry reform, agricultural economic development, rural revitalization, and the characteristics of agricultural industry layout.

  • Agriculture and Landscape Ecology
    HUA Chunlin, ZHANG Jiuhong, ZHANG Canqiang
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    The active utilization and inheritance of agricultural heritage cannot be separated from the support of relevant government policies. This study combined the bibliometric method and content analysis method to analyze the agricultural heritage protection and development policies based on the government’s 410 agricultural heritage official documents and constructed a six-dimensional analysis framework of document release form, release subject, release quantity, document relevance, document type, and document content. The results show that the form and subject of document release are diversified; the number of documents released has an approximate inverted “U”-type characteristic; the number of documents formulated specifically for agricultural heritage is relatively small (21.46%); and information documents and guidance documents are more favored by the government than incentive documents. The discussion of the document content demonstrates that the excavation and application of agricultural heritage are worthy of further improvement; the economic value is widely used in the multifunctional utilization of agricultural heritage; and farmers, enterprises, scientific research institutions, and governments are all crucial participants in the management of agricultural heritage. Some problems remain in the government’s management of agricultural heritage, such as producing too few targeted documents and the insufficient coverage of the documents that have been produced thus far.

  • Agriculture and Landscape Ecology
    WANG Xin, LIN Dayi, HAO Haiguang
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    The dominant livelihood types of farm households have become increasingly differentiated in recent years, which has attracted the attention of researchers. Identifying the characteristics and driving factors of household livelihood differentiation is of great significance for revealing man-land relationship and policy making. Based on the interview data of farm households in typical villages in key ecological function areas of Ningxia Hui Autonomous Region in China, we analyzed the pattern of the dominant diversified livelihood types and the livelihood characteristics among different farm households. Then we assessed the driving forces of livelihood diversification by optimal scaling regression. The results indicated that: (1) In the study area, the dominant livelihood types show two trends of agriculturally dominant livelihood (accounting for 53.07%) and non-agriculturally dominant livelihood (accounting for 46.93%). Moreover, farm households in the agro-pastoral areas are mainly agriculturally dominated (accounting for 75.68%), while farm households in the mountainous areas are mainly non-agriculturally dominated (accounting for 66.93%). (2) The labor allocation and income source of different types of farm households are consistent with their dominant livelihood types. The farm households with agriculturally dominant livelihoods have more natural resources than those with non-agriculturally dominant livelihoods. In terms of housing conditions, farm households with agriculturally dominant livelihoods are inferior to those with non-agriculturally dominant livelihoods. (3) The farm labor, dependency ratio, agricultural income, supplemental income and locational conditions have negative impacts on the non-agricultural trend of farm household livelihood decisions, while off-farm labor, non-farm income, education level and the per capita amount of compensation have significant positive impacts on it.

  • Agriculture and Landscape Ecology
    ZHOU Lian, HUANG Xueyuan, ZHANG Lei
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    Traditional rural homegarden agroforestry systems in the Chengdu Plain of China are often referred to as “Linpan” in Chinese, which integrates the landscape of ecological functions and human production activities. In recent years, due to the influences of urbanization and the aging population, the Linpan landscape has changed dramatically. Clarifying the factors which influence Linpan landscape evolution is a critical way to improve rural landscape renovation. Through oral history interviews, the deep-seated factors driving the evolution of the Linpan landscape form from 1949 to 2020 are explored using the grounded theory. The results show that in the process of Linpan landscape evolution, beneficiary groups, the material basis, and cultural characteristics are the prerequisites for changing the Linpan settlement landscape. The demand of production and life and government-led behavior are the two main influencing factors, and landscape change is the final result. The demand of production and life from the residents is the primary internal driving force of landscape change, while government-led behavior is the main external driving force of settlement development and evolution. The nature of the main driving forces behind the evolution of the Linpan landscape in the Chengdu Plain can be divided into three stages. (1) From 1949 to 1980, it was characterized as a balancing of government forces and social forces. (2) From 1981 to 1993, it was characterized by social forces suppressing government forces. (3) From 1994 to 2020, it was characterized as a stalemate between the government and social forces. From the perspective of the evolution of the Linpan settlement landscape, the traditional Linpan form and settlement layout have been unable to meet the new requirements of the rural social and economic transition period. They are facing the challenges of rural reconstruction and rural revitalization. In the future, village and town planning and the design of new settlements need to comprehensively consider the demands of different interest groups.

  • Agriculture and Landscape Ecology
    YANG Baoqi, SONG Shuqiao, QIN Jing
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    Analyzing the landscape pattern of rural settlements is an important way to reveal the relationships between landscape change and human activities. Based on Landsat TM/ETM/OLI satellite remote sensing images as data sources and Hejiang River Basin as the research area, this paper expounds the information on the spatial distribution of rural settlements at four time points in 1990, 2000, 2010 and 2020. Using the methods of landscape pattern analysis, GIS spatial analysis and spatial statistics, this paper analyzes the spatial characteristics of the rural settlements, such as scale, distribution and shape, and then discusses the influences of terrain, rivers, location and policy factors on the spatial characteristics of the rural settlements. The results show that with the advance of time, the number of rural settlement patches in Hejiang River Basin is decreasing, the patch area and average patch area are increasing, the patch density is decreasing, and the settlement pattern tends toward cluster development. In addition, the shapes of settlement patches tend to be complicated and irregular, so it is necessary to strengthen planning and guidance in order to promote the regular layout of the settlements. The overall distribution of settlements is dense in the Northwest and Southeast, but sparse in the Middle and West, with a high density in the plains and a low density in hills and mountains. This study found that the terrain, river and location factors have significant influences on the spatial pattern of settlements.

  • Ecosystem Assessment
  • Ecosystem Assessment
    GUO Xuan, GUO Qun, LI Yu, LI Shenggong
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    Quantitative assessments of ecosystem service value (ESV) are of great significance for rational allocation of environmental resources and making regional ecological protection decisions. The method of equivalence factor per unit area is widely used for this purpose because of its simple algorithm. However, ESV is also affected by biotic and environmental factors (e.g., net ecosystem productivity (NEP) or precipitation), which are difficult to obtain at the regional scale, leading to uncertainty in ESV estimations. In this study, according to the equivalent factor modified by precipitation and NEP from four state-of-the-art process-based productivity models, i.e., CLM4.0, LPJDGVM, LPJGUESS and ORCHIDEE, we explored the temporal and spatial patterns of ESV of 15 administrative regions in northern China. The results show that the simulation accuracy of different models varied among four representative ecosystem types, i.e., typical steppe in northern China, alpine steppe in northwest China, farmland ecosystem in central China, and forest in northeast China, implying that model-based ESV estimates are ecosystem-specific. The ESV tends to decline from northeast to southwest in northern China. Regions with dense vegetation usually had high ESV due to better hydrological and thermal conditions. Low vegetation coverage areas, such as Qinghai and Xinjiang, had higher ESV because of their large geographical areas. The central and eastern developed regions without abundant natural resources had lower ESV due to their lower NEP. For different categories of ecosystem services, the regulation services (mainly water flow regulation services and climate regulation services) contributed the most to ESV. For the temporal dynamics, the total ESV of the 15 provinces, autonomous regions and municipalities showed an insignificant downward trend over the years. The regions with increasing trends of ESV were distributed in northwestern China, while pixels with decreasing trends of ESV were concentrated in northeastern China. Land use cover change may be the most important factor controlling the temporal dynamics of ESV. Our results can provide support for the enaction of reasonable strategies for ecological protection and economic development in northern China.

  • Ecosystem Assessment
    WANG Yongxiang, WEI Jiaxuan, ZHOU Juan, YANG Jiajia, XU Yuanyuan, CHEN Yuxin, HAO Jiangcheng, CHENG Wuxue
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    This paper took the Nyingchi area in southeastern Tibet Autonomous Region of China as the research area, and selected five indicators of elevation, slope, slope direction, normalized difference vegetation index (NDVI) and water body as the evaluation system based on the current situation of domestic and foreign research and field investigation. The indicators were analyzed by the AHP method for weighting, and then an ArcGIS overlay analysis was applied. The results show that the ecological sensitivity of the Nyingchi region is generally increasing from the south of Nyingchi to the north of Nyingchi. The northern, western and southwestern parts of Nyingchi are extremely sensitive or highly sensitive, while the southern part is mostly insensitive or mildly sensitive ecologically. The proportions of areas for each sensitivity level are: not sensitive 54.81%, light sensitive 11.97%, moderately sensitive 10.34%, highly sensitive 8.65%, and extremely sensitive 14.23%. The results indicate that the overall ecological sensitivity of the Nyingchi region is low and this region is performing well with respect to ecological environmental protection. This study can provide some suggestions for targeted improvements of the ecological environmental protection in the Nyingchi region and even in the Tibetan Plateau region.

  • Ecosystem Assessment
    ZOU Jingru, LI Shuai
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    Elevated CO2 (eCO2) has important impacts on plants, especially on water use efficiency (WUE). A meta-analysis was performed to determine the responses of WUE to enriched CO2. We summarized 242 studies on WUE research under ambient and enriched CO2 conditions that were published between 1989 and 2019. Our results showed that WUE had positive responses to elevated CO2 with an increase of about 46% and high heterogeneity. Elevated CO2 increased leaf, grain, biomass and whole plant WUE by 76%, 9%, 30% and 37%, respectively. The effect size on leaf WUE was higher than the other three WUE types, and the effect size on whole plant WUE was higher than grain WUE (P<0.05). In another respect, the response of WUE in forests was higher than in cropland (P<0.05). Regarding different experimental methods, WUE had a stronger response to elevated CO2 by the method of climate-controlled chamber than by the methods of OTC (Open Top Chamber) or greenhouses (P<0.05). However, the effect size obtained by the method of greenhouse was higher than that obtained by the methods of either OTC or climate chamber for whole plant WUE (P<0.05). Furthermore, our results found WUE had a positive linear relationship with the magnitude of CO2 enrichment (P<0.05). Meanwhile, the effect size of elevated CO2 on grain WUE had a positive linear relationship with the duration of CO2 enrichment. This study found that the impacts of CO2 enrichment on WUE are unique and specific for different WUE types and the various experimental conditions.

  • Ecosystem Assessment
    WANG Shuang, ZHEN Lin, XIAO Yu, WEI Yunjie, HU Yunfeng, YOU Dongmei
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    In the face of increasingly severe ecological degradation in the typical fragile ecological regions around the world, many different ecological technologies (ET) have been developed. However, there is still a lack of any comprehensive analysis of these technologies and the effects of their implementation on regional ecological systems, and this largely limits the promotion of the excellent technologies and their applications. Based on the Web of Science core online database and specific literature screening criteria, 3409 papers were selected to summarize and analyze the development trends, research hotspots and regional comparisons of ecological technology effect research. Furthermore, 19 publications from 14 regions were selected to compare and analyze the effects of eight commonly applied ET: shelterbelt, artificial afforestation, water-saving irrigation, terrace, stereo-agriculture, contour tillage, ban/rest/rotational grazing and fallow/no tillage/minimum tillage. The results show four key features: (1) The research on the effect of ecological technology is still in the period of continuous development. (2) “Erosion” is the largest node in the keyword co-occurrence map of ecological technologies effect research, followed by “management”. (3) Most countries pay attention to the studies of “erosion” and “runoff”, although there are differences in research on the effects of ecological technologies in different countries. (4) The same technology could be applied to different regions but the effects varied, and the ecological technologies that have been implemented have generally achieved good restoration effects; however, the improper use of ecological technologies may bring negative consequences. This study provides important support for ecosystem restoration and improvement in the ecologically degraded areas in China and around the world, and it provides a reference for the export and introduction of excellent technologies.

  • Ecosystem Assessment
    ZHANG Changshun, XIE Gaodi, ZHEN Lin
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    Research on ecosystem service consumption not only helps to reveal the utilization intensity and management level of the ecosystem in Guilin, but it also provides a scientific basis for ecosystem investment, trade, subsidies and taxation by the Guilin government departments. Based on household survey data of urban and rural ecological consumption, the physical quantity accounting method is adopted for multivariate statistical analyses, such as analysis of variance and multiple comparison. This analysis reveals the differences and changes in the consumption level, consumption structure and consumption pattern of the main ecological products in Guilin among the various counties. The results fit into four main themes. (1) The annual per capita consumption of the main ecological products in Guilin varies either extremely significantly or significantly among the counties, but the consumption level of ecological products varies according to the type of products. There are significant or extremely significant differences in the annual per capita consumption of cereals, melons and fruits, pork, poultry, beef and mutton, fresh eggs and milk between urban and rural residents. (2) There are extremely significant differences in the annual per capita consumption of fruits, pork, poultry, beef and mutton, fish, fresh milk and vegetable oil among urban residents in different counties. There are also extremely significant differences in the annual per capita consumption of cereals, pork, poultry and alcohol among rural residents in different counties, and significant differences in the annual per capita consumption of fresh eggs and milk. The consumption level of ecological products by urban and rural resident varies with the type of products. (3) The ecological consumption patterns of all counties in Guilin mainly follow the “cereal + vegetable + fruit + meat” pattern for urban residents and the “cereal + vegetable + meat” pattern for rural residents (except for the rural residents in Pingle, which show the “cereal + vegetable” pattern). The consumption structure of urban residents is better than that of rural residents. (4) There is a large gap between the ecological consumption of urban and rural residents in Guilin and China's recommended standards, except for cereals and meat. The main problems are excessive meat intake, and insufficient intake of dark vegetables, fruits, eggs, milk and fish. Therefore, we should make full use of forestland, grassland, water and other resources in the area, and vigorously develop fishery, fruit and vegetable production and herbivorous animal husbandry to meet people's ecological needs for dark fruits and vegetables, eggs, milk and fish in Guilin City.

  • Ecosystem Assessment
    LIU Jia, XIAO Yu, HUANG Mengdong, ZHANG Changshun, QIN Keyu, XU Jie, LIU Jingya
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    The water supply services of the Li River are essential for the ecological environment and local social development. Based on the InVEST model, we quantitatively analyzed the spatial and temporal distribution patterns of water supply services in the Li River Basin from 2000 to 2018 at multiple scales, including the raster, sub-basin, and regional scales, clarified the differences in water yield among different land use types, and explored the different stages of changes in the characteristics of water services. The results revealed four key aspects of this system. (1) The water supply service of Li River Basin showed a spatial distribution pattern of high in the north and low in the south, and the water yield gradually decreased from north to south. (2) Among the various land use types in Li River Basin, the average water supply capacity decreased in the following order: artificial surface, unused land, grassland, forest, cropland and wetland. (3) The average amounts of water services in the 18 sub-basins varied widely, with four sub-basins belonging to the high-value area for water supply services, eight in the middle-value area, and six in the low-value area. (4) From 2000 to 2010, the regions with large fluctuations in water supply services include the midstream region, Lipu River region, and the northern region of Gongcheng River; while from 2010 to 2018, the areas with large fluctuations were in the midstream region and Gongcheng River region. The results of this research increase our understanding of the water supply services in the Li River Basin and provide a critical scientific basis for the reverse compensation of a regional ecological compensation mechanism.

  • Ice-snow Tourism
  • Ice-snow Tourism
    Laurent VANAT, LI Yu
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    The global ski tourism market has been in a relatively mature period. However, passenger flows are stagnating in many countries and the growth perspectives are not very appealing. This change of the tourism market troubled the entire ski industry with new challenges, leading to the ski tourism industry model established in the 20th century failing to meet the current development needs. According to multiple data sources, including relevant industry reports and the latest data from internetm, this article based on a variety of these reports and the latest data from website, analyzed the ski tourism market’s both sides of supply and demand, systematically summarized the evolution of ski tourism industry since the 21st century, discussed the process of the ski tourism industry’s development and the economy’s growth, and revealed the relationship between the influencing factors of ski tourism market’s potentials. Meanwhile, the main problems and challenges in the ski market were also summarized. The results showed that global ski tourism had entered a mature stage since the beginning of 2000. Moreover, there was a specific correlation between skiing participation rate and GDP, which varied with the regional economic level and the maturity degree of skiing industry. Despite some impacts from COVID-19, the ski industry in most regions exhibited signs of recovery in 2021. The Winter Olympic Games in China have brought new opportunities to the skiing industry and have been expected to encourage global participation in skiing. However, some existing ski resorts in different countries and regions may not significantly contribute to the future development of global ski tourism, and the potential growth of ski tourism market might be small and mainly concentrated in China. At present, the biggest threat to the ski market is baby boomers having long been the bulk of ski resort visitors. The ski market is faced with this aging problem and the widespread phenomenon of ski culture fault. How to meet the needs of this new generation of customers who lack ski backgrounds or cultures is a severe challenge for all emerging and existing ski resorts around the world. Besides, public transport accessibility, service quality and resorts operation capacity have also been the improvement direction of the ski market in dire need.