As the Earth entering into the Anthropocene, global sustainable development requires ecological research to evolve into the large-scale, quantitative, and predictive era. It necessitates a revolution of ecological observation technology and a long-term accumulation of scientific data. The ecosystem flux tower observation technology is the right one to meet this requirement. However, the unique advantages and potential values of global-scale flux tower observation are still not fully appreciated. Reviewing the development history of global meteorological observation and its scientific contributions to the society, we can get an important enlightenment to re-cognize the scientific mission of flux observation.

Rapid economic development, industrialization, and urbanization aggravates the tense relationship between human beings and the land. With multiple demands for food security, ecological protection and economic development, frequent conflicts and competition occur between multiple different functional land types. The current land use classification system focuses on the productive and living functions of land, but gives little consideration to ecological functions. This study builds a national Ecological-Living-Productive Land Classification System based on land functions emphasizing the concept and position of ecological land. So-called ecological land uses are types of land use regulating, maintaining and protecting ecological security. The new land classification is more flexible for overall planning purposes and for making arrangements for ecological, living and productive land spaces. The Ecological-Living-Productive Land Classification System includes three levels. The first level has four major types: ecological land, ecological-productive land, productive-ecological land, and living-productive land. The second level subdivides the major types into 15 functional land categories, including major ecological regulation land, common ecological regulation land, and ecological conservation land for ecological lands; pasture land, timber land and aquaculture land for ecological-productive lands; arable land and orchard for productive-ecological lands; and urban built-up area, rural living land, and industrial land for living-productive lands. The third level is based on land cover types. Based on multiple data sources, and using a strategy of zoning and re-classification, we extracted the spatial distribution of ecological-living-productive lands on a national scale. The areas of ecological land, ecological-productive land, productive land, and living-productive land area are 6,037,000 km², 1,353,800 km², 2,001,900 km² and 207,300 km², respectively; accounting for 62.89%, 14.10%, 20.85% and 2.16% of total area, respectively. For the second-level classification, the area of ecological conservation land is the largest, accounting for 20.17% of the total area. Ecological land is located mainly in central and western China. Ecological-productive land is distributed in various areas throughout the country, and productive-ecological land and living-productive land are concentrated in eastern China.

Transboundary rivers have important geopolitical and geo-economic connotations, but riparian states of transboundary rivers are often driven by their own rapid population growth and economic development to become involved in regional conflicts about the development and use of water resources. Therefore, finding a balance between the need for fair and reasonable development of water resources and the effective protection of environment from an ecological perspective has become a major problem faced by the international community. This paper begins with consideration of international water laws related to transboundary rivers and then reviews advances in the research on benefit-sharing, ecological compensation mechanisms, and adaptive management systems. We believe that existing international water laws form a complete legal system and that more attention needs to be paid to transboundary cooperation and sustainable water resource use. With respect to how transboundary water conflicts are resolved, there is a trend to move away from single water resource allocation (a zero-sum game) to benefit-sharing in order to achieve a win-win situation for riparian states, but there are still some difficulties in transboundary ecological compensation. In China, the central government has paid attention to horizontal ecological compensation between upstream and downstream, offering guidance to promote establishment of inter-province ecological compensation. Based on existing practice, horizontal ecological compensations are still in their infancy, small in scale, supported by a weak legal system, lacking market mechanisms to encourage their use and relying on fiscal transfers as the method of payment. In the future, China will need to intensify its research on legal system development, international cooperation, and benefit-sharing as these impact transboundary water resources. Because government can be seen as a management department with multiple identities (enabler, regulator and buyer), to improve adaptive transboundary ecological compensation mechanisms, government must develop as soon as possible data sharing platforms, standards of water consumption behaviors and intergovernmental policies (or ordinances).

An increase in the extremality of natural processes is a consequence of warming, aridization, and desertification. The authors consider the processes of warming, aridization, and desertification to be the parts of a single system and major destabilizing factors of ecological balance. Destabilization is expressed in the growth of natural processes extremality. Ecosystems of Transbaikalia were once characterized by a different natural contrast and amplitude. Warming, aridization and desertification have led to an increase of environmental regimes tensions. This is demonstrated quantitatively by the root-mean-square difference of atmospheric and soil parameters. Quantitative indicators of aridization are estimated using Walter-Gossen climate charts. Permafrost zone response information to the long-term warming is provided as well.

The formation of tree-rings is closely related to climate variation. This paper establishes the tree-ring chronology of Pinus massoniana for a period of 36 years and examines the relationship between the tree-ring chronology and climatic conditions based on tree-ring width samples from three sites on the northeast slopes of Yangming Mountain. This data is used to study the relationship between the tree-ring width of a young tree and climatic conditions in a moist hilly region of southern China and to understand the general pattern of climate variation and its effects on tree growth in the past in this region. The results indicate that changes in tree-ring widths in these sites are closely related to local climatic conditions. There is a significant positive correlation between the radial growth of Pinus massoniana and the mean temperature of the current year from January to May (coefficient of correlation, R, is 0.596, P<0.01) and the mean temperature of the previous year from June to July (R is 0.639, P<0.01). The radial growth of Pinus massoniana is negatively correlated with the total precipitation of the previous year from January to March and November to December (R is -0.46, P<0.05) and negatively correlated with the total precipitation of the previous year from June to July (R is -0.582, P<0.05). The effect of precipitation on the radial growth of Pinus massoniana is known as the “hysteresis effect”.

Understanding how nitrogen (N) availability interacts with soil acidity and phosphorus (P) availability to affect soil-atmosphere exchanges in CO₂, CH₄ and N₂O in forest ecosystems is important for understanding the mechanisms driving ecosystem responses to enhanced N deposition. Here, we conducted an experiment with N, P and acid (H) addition in a mixed forest in subtropical China to investigate how acid and P addition affects CO₂, CH₄ and N₂O exchange under N addition. Our results showed that soil -N and -N increased after N addition, but CO₂ emissions in N addition plots remained unaffected. CH₄ uptake in N-, P-, NP-, NH- and NPH-addition plots were reduced by 21.1%, 15.7%, 39.1%, 26.6%, and 28.4%, respectively. CH₄ uptake in NP-addition plots were lower compared to N-addition and P-addition plots, indicating that N and P addition had an additive effect on inhibiting CH₄ uptake. N₂O emission in N-, NP-, NH- and NPH-addition plots increased by 158.6%, 176.0%, 117.2%, and 91.8%, respectively. N₂O emissions in NPH-addition plots were lower compared to NP-addition plots while showed no difference between N-addition and NH-addition plots. This suggests that only under P rich conditions, acid addition would greatly mitigate N₂O emissions under N addition. Our results demonstrate that for N and P co-limited forest ecosystems with acidic soils, low P availability constrains the inhibition of soil CH₄ uptake by N deposition. When P availability is low, a weak soil acidation induced by N deposition may have less influence on the stimulation of N₂O emissions by N deposition.

The fractal characteristics of drainage in the ten kongduis of the upper Yellow River were obtained using the box counting dimension, and the evolution stages of the watershed topography were defined by different ranges of the fractal dimensions of river networks (D_g). The results show that the fractal scaleless range of the Maobula River is 20–370 m based on a combination of artificial judgment, correlation coefficient test and fitting error. Other kongduis show good fractal characteristics in this fractal scaleless range as well. The box counting dimension can be used as a quantitative index of watershed topography fractal characteristics. The fractal dimension of stream networks is independent of the threshold contributing area used for extracting the drainage networks from the DEM. The values of D_g in the upper ten kongduis are in the range of 1.08–1.14. Both the runoff yield and the sediment yield are positively and linearly related with D_g. The positive relation between the sediment yield and D_g reflects the effect of landform features on sediment yield in the young and/or mature stages of landform evolution of the study area. By revising the critical value of D_g, the value of D_g of the basin in the young evolution stage is less than 1.06, while it is more than 1.06 for the basin in mature or old evolution stage. The upper ten kongduis are in the mature stage of landform evolution.

Wavelet analysis and Mann-Kendall tests are employed to evaluate the variation in the East Asian summer monsoon (EASM) and hydrological variables in the Haihe River basin calculated by the Variable Infiltration Capacity model. The relationships between those variables and the EASM are also examined. The results indicate consistent 40a periodic variation in both the hydrological variables and the EASM. The hydrologic variables show downward trends in the Haihe River basin over the past 60 years, especially in piedmont regions of the Taihang-Yan Mountains. The variables are closely related to the EASM, whose continuous weakening since the 1970 s has resulted in prolonged drought and severe water shortages in the basin. The periodicity of the EASM index was analyzed using continuous wavelet transform methods. We found the most significant periodic signal of the EASM is ∼80 years; therefore, the EASM may reinforce and reach a maximum in the 2040 s, resulting in more precipitation and other impacts on basin water resources. Hydrologic variables in the basin in the 2040 s are predicted, and their spatial distributions in the Haihe River basin are also discussed. These results allow for the estimation of water resources under forecasted EASM, which will be useful for water resources management in the Haihe River basin.

Mechanisms of kin selection have been studied to explain how siblings grow together, but the findings remain controversial. This can be ascribed to the use of single indicators without considering other factors. Three ecotypes of Arabidopsis were used to examine kin responses of siblings growing together. Plant traits of leaves, plant shape, reproductive activity, and roots were investigated. We found that Arabidopsis recognized their kin neighbors, showed selective responses to distinct plant traits among ecotypes, and modes of responses were dependent on neighbor's growing distance. If single traits were used to judge kin response performance, the results were chaotic. However, by developing and studying an integrated performance value based on multiple traits, we determined that Ler showed similar integrated performances at all planting distances, while the integrated performance of Col was ranked mainly as medium distancedistance> small distance> large distance, which suggested kin cooperation. However, in comparison to medium and small distances, at which performance was consistent with kin recognition, we found that at large distance, strangers of Ws performed better than kin plants, which suggested competition. Thus, we conclude that kin recognition could be affected by plant competition conditions that are the result of growing distance, and that the integrated performance of individuals was more suitable to evaluate kin interactions of plant species.

In this paper, changes in the amounts of organic carbon and black carbon in reclaimed soil were studied. The subsidence area was in a Xuzhou coal mining area that is part of a national land reclamation demonstration area. The significance of the paper is to explain the law of quality changes of reclaimed soil, improve the soil reclamation process and promote the sustainable use of soil in mining areas. In the study, four kinds of soils were collected using four land reclamation methods: coal gangue filling (CGF), mixed flat reclamation (MFR), mud pump filling (MPF) and fly ash filling (FAF); soil from the subsided area (SS) was used as the control. Organic carbon and black carbon on content were determined by elemental analysis, potassium dichromate titration and other methods. The result shows that reclamation methods do have an influence on the organic carbon and black carbon content in subsidence soil. The content of organic carbon and black carbon at different soil depths varies the most in FAF. Regression analysis of black carbon and organic carbon contents from the four different reclamation methods show that the levels are significant in all cases. Therefore, there is no obvious relationship between the proportion of black carbon and the accumulation of organic carbon in the study area.

The concept of climate carrying capacity has been proposed recently for climate risk management. Based on identification of the concept of climate carrying capacity and analysis of the relationship among its influencing factors, this study established a comprehensive assessment indicator system of climate carrying capacity from aspects of the climate situation, the level of climate usage, and the development potential of cities. Taking Shanghai City as a case study, we developed a quantitative assessment model of climate carrying capacity. The climate carrying capacity and its influencing factors were analyzed and discussed in relation to the period 2004–2013. The results were as follows. (1) Current climate natural capacity indicator showed that the climatic situation of Shanghai City was inferior to its base climatic value and it had been in a state of fluctuation. (2) The climate stress and urban coordinated development capacity indicators increased steadily, but the growth rate of the urban coordinated development indicator was less than the growth rate of urban climate stress. (3) The climate carrying capacity was far lower than the benchmark value and it had been in a state of fluctuation mainly due to the effect of current climate situation. (4) According to a principal component analysis, seven factors of urban population density, per capita GDP, energy consumption per unit GDP, total industrial output value, investment in environment protection, spending on science and technology, and green area per capita were main influential factor of climate carrying capacity. It was proved that the proposed system for assessment of climate carrying capacity of a city was feasible. It can be used to describe the spatiotemporal changes of cities, and identify problems of regional climate carrying capacity associated with their development and function. This assessment system can provide a reference for the construction of an early warning system of climate carrying capacity for cities.

Water resources insufficiency is one of the bottlenecks that restrict sustainable socio-economic development in Ningbo city. Good handling of the relationship between water resources utilization and development is of great significance for the realization of continuous economic growth and sustainable socio-economic development. This study systematically evaluated water resources utilization with respect to water supply and demand. Water resources development and utilization prospects and regional differences were then assessed at multiple scales, at both county/district and city level in Ningbo city, using the water resources carrying index. Results showed that: (1) The volume of water resources supply and consumption gradually rose each year, with surface water as the primary source and groundwater as the secondary source. Regarding consumption, industrial water consumption was the primary element, and domestic and environmental water consumption were the secondary elements. Even though the use of water resources for irrigation, secondary and, tertiary industry were becoming more efficient, comprehensive per capita water consumption was gradually increasing. (2) The water resources carrying index for Ningbo city fluctuated in the range of 4.51–23.35 during 2001–2015; the degree of water resource utilization and potential exploitation evaluation of water resources were not stable. The average value of the water resources carrying index was 11.68; the degree of utilization of water resources was very high, and the introduction of water from external water bodies was necessary, to the extent external source were available. (3) Future water resources exploitation will be quite difficult in Ningbo city, especially in Cixi county, Ningbo municipal district and Yuyao county. So the introduction of external water as a supplemental source will be required.