Long-distance trails serve as essential infrastructure linking humans and nature. Currently, most trail planning relies on suitability analysis, which assesses areas rather than routes and often results in discontinuous trails. Using the Taihang Mountain National Forest Trail - Beijing Section (TMNFT-BS) as a case study, this study proposes an integrated framework for trail planning. Based on hiking trajectory data, we use landscapes and wilderness continuum map for screening conditions to locate a trail. The resulting TMNFT-BS trail is approximately 179.8 km in length and: (1) follows only existing routes, minimizing ecological impacts and costs; (2) is continuous and accessible; and (3) traverses areas with the highest average wilderness quality while linking diverse landscapes, providing a rewarding hiking experience. This study introduces a novel approach to the longest path problem in general graphs and presents a trail-planning methodology applicable in China and beyond.

Climate change is expected to intensify over the coming decades, potentially exerting substantial impacts on above‐ground net primary productivity (ANPP), a key indicator of ecosystem functioning and carbon sequestration. However, decadal cooling phases remain underexplored, and phenology is rarely integrated explicitly as a cascading mediator linking temperature to plant growth and ANPP. Consequently, the long‐term effects of climate change—particularly those associated with cooling phases—remain poorly understood. Based on a reciprocal transplant experiment initiated in 2007 in an alpine grassland, we measured ANPP, plant growth dynamics, flowering species composition, and phenological events. After 15 years, ANPP increased under warming but decreased under cooling. However, only the warming effect intensified over time, whereas the cooling effect showed no detectable temporal trend. Importantly, both warming and cooling effects on ANPP were integrated by early‐season phenology. Under warming conditions, earlier leaf‐out and accelerated growth rates corresponded with higher ANPP. However, leaf and flower phenology showed decoupled cascading effects on growth under cooling conditions: delayed leaf‐out inhibited plant growth, while delayed flowering partially mitigated this suppression. Synthesis . Therefore, extrapolations based solely on short‐term warming manipulations, neglecting both the differences in long‐term warming effects and the cooling phases with their distinct ecological mechanisms, will lead to inaccurate long‐term predictions. Our findings demonstrate that changes in plant phenological events mediate the impacts of decadal climate warming and cooling on ANPP in alpine grasslands, providing more comprehensive insights into how alpine ecosystem carbon cycling may respond to long‐term climate change.

Biodiversity conservation amidst the uncertainty of climate change presents unique challenges that necessitate precise management strategies. The study reported here was aimed at refining understanding of these challenges and to propose specific, actionable management strategies. Employing a quantitative literature analysis, we meticulously examined 1268 research articles from the Web of Science database between 2005 and 2023. Through Cite Spaces and VOS viewer software, we conducted a bibliometric analysis and thematic synthesis to pinpoint emerging trends, key themes, and the geographical distribution of research efforts. Our methodology involved identifying patterns within the data, such as frequency of keywords, co-authorship networks, and citation analysis, to discern the primary focus areas within the field. This approach allowed us to distinguish between research concentration areas, specifically highlighting a predominant interest in Environmental Sciences Ecology (67.59 %) and Biodiversity Conservation (22.63 %). The identification of adaptive management practices and ecosystem services maintenance are central themes in the research from 2005 to 2023. Moreover, challenges such as understanding phenological shifts, invasive species dynamics, and anthropogenic pressures critically impact biodiversity conservation efforts. Our findings underscore the urgent need for precise, data-driven decision-making processes in the face of these challenges. Addressing the gaps identified, our study proposes targeted solutions, including the establishment of germplasm banks for at-risk species, the development of advanced genomic and microclimate models, and scenario analysis to predict and mitigate future conservation challenges. These strategies are aimed at enhancing the resilience of biodiversity against the backdrop of climate change through integrated, evidence-based approaches. By leveraging the compiled and analyzed data, this study offers a foundational framework for future research and practical action in biodiversity conservation strategies, demonstrating a path forward through detailed analysis and specified solutions.

Investigating surface dry-wet patterns on the Qinghai Plateau (QP) is crucial for water allocation, ecological sustainability, and climate variability adaptation strategies. Existing discrepancies in the QP dry-wet trends and distribution characteristics underscored the need for a more refined analysis. This study utilized the Thornthwaite Moisture Index (IM) to quantify changes in surface dryness and wetness under prevailing climatic conditions. Linear trend regression and ensemble empirical mode decomposition (EEMD) were applied to study the dynamic and periodic characteristics of the QP from 1980 to 2018. Our findings revealed a decrease from southeast to northwest in IM, with the semi-arid and sub-humid transition line aligning closely with the 400 mm isohyet. The dry-wet transition line exhibited a northwestward trend over the past four decades. Possibly influenced by monsoon circulation and El Nino-Southern Oscillation (ENSO), the annual IM displayed a quasi-cycle of 3 to 5 years, manifested by a dry period (1990-2004) and a wet period (2005-2012). However, spatial differences existed, challenging the universality of the "Dry gets Drier and Wet gets Wetter (DDWW)" pattern. Precipitation (PRCP) changes could predict over 90 % of IM spatiotemporal variations. Additionally, the IM response to Average Temperature (TAVG) exhibited an inverted U-shaped curve, with a boundary (-3.8 degrees C) below which cooler regions became wetter and above which they became drier. The observed warming and precipitation shifts suggested that continued warming could lead to warmer and wetter climates, potentially causing ecological and environmental problems. Therefore, examining the surface moisture budget is of critical scientific and practical significance, in order to provide a decision- making basis for mitigating and adapting to climate change.

The fraction of absorbed photosynthetically active radiation (FPAR) is a key biophysiological parameter of terrestrial ecosystems. However, due to a lack of data with adequate spatial resolution and in long enough time series, there have been limitations in exploring the spatiotemporal changes of vegetation and response to climate change. In this study, a 1 km spatial resolution and 8-day period length dataset (FPARANN) was developed covering the years 1980 to 2018 and evaluated on spatiotemporal change consistency by validating with Gross Primary Production (GPP) observations from the Chinese Flux Observation and Research Network (ChinaFLUX), and comparison with other FPAR products. FPARANN provided a comparable performance in capturing seasonal change observed through GPP, according to the coefficient of determination (R2): 0.50, 0.51, 0.70 and 0.74 averaged for all sites, forest sites, grassland sites and cropland flux sites, respectively. The new data had more spatial similarity to the MODIS FPAR product (FPARMCD15A2) with a greater R2 (0.77) and a lower RMSE (0.12) than other products. With a newly developed dataset, combined with FPARANN (1980–2003) and FPARMCD15A2 (2004–2018), an overall increasing trend in FPAR was found for over 81% of the vegetated area of China from 1980 to 2018. FPAR increased more rapidly for over 83.7% of the area in the 2010s, and at a slower pace for over 62.1% of the area in the early 2000s, which was attributed to a decadal shifting of climate change. This study implies the new dataset is useful in quantifying vegetation changes and would be an important data source for future study of the carbon cycle, soil erosion, or evapotranspiration, with great application potential.

科学的空间关系和合理的空间结构是保护地治理的基础,美国大黄石生态系统(简称"大黄石")是多种单元协调共生的保护地集群典范.经过150多年4个时期的建设,大黄石保护地单元空间关系中的边界重叠问题逐步解决,外部相依和内部嵌套相继建立,在更大范围形成土地利用共生圈层和景观尺度的空间相依关系;保护地集群形成了以国家公园为核心、国家森林为主体、其他类型保护地填补空缺的空间结构;"基础—路径—目标"框架可以解释该结构的形成原因,土地权属、政府治理及资源保护利用是保护地集群形成的物质基础、发展路径及建设目标.对中国的启示:空间管控要关注保护地单元的空间关系和保护地集群的空间结构;政府治理要将自上而下、自下而上的方式相结合.

Vegetation response to climate change can be characterized as long-term trends, but with periodic oscillations. Revealing vegetation response trends, with oscillations, is essential for formulating climate change mitigation and adaptation planning, as well as adopting ecological protection and restoration measures. Here, the long-term trend and periodic oscillations in vegetation changes were explored through a measure of gross primary production (GPP), an indicator of vegetation photosynthesis, using data of both high spatial resolution (1 km2) and a long-term of nearly 4 decades, from 1980 to 2018. The GPP data were estimated for China's terrestrial ecosystem and validated against the eddy covariance-based observations of 70 site-year in China and compared to other GPP data products. The results showed the estimated GPP can explain 76% of spatial-temporal variance with the same data accuracy as other products, but with the advantage of both high spatial resolution and long time periods that other products do not have. From the estimated GPP data, Chinese terrestrial vegetation growth was found to have a periodic oscillation of close to 2.79 years and a long-term increasing trend of 59.8 Mt C m � 2 per ten years over 92% of all vegetated land in China from 1980 to 2018. Moreover, it was found that vegetation growth accelerated significantly in the two recent decades over the previous two decades. The growth rate was 83.5 Mt C a-1 from 2000 to 2018, which was 2.31 times faster than the rate from 1980 to 2000. The underlying mechanism of the vegetation responses was analyzed by ridge regression, a method to decrease the effects of multicollinearity. Long-term variability and trends in vegetation could be attributed to a warming minimum air temperature when examined with precipitation, maximum air temperature, and solar shortwave radiation. Though more influences, such as those from freezing and thawing and human activities, should be explored in the future, this study offers insight that warming, with increasing daily minimum temperatures, is likely to be a vital contributor to ecosystem changes, and will be essential knowledge for mitigation of effects and adaptation to future climate.

The alpine grasslands of the Qinghai-Tibetan Plateau play an important role in multiple ecosystem functions, all of which are key in regulating regional climate influences and providing pristine headwaters for millions of people downstream from this basin. Alpine grasslands act as a carbon sink, storing carbon dioxide and keeping heat-trapping greenhouse gases out of the atmosphere, but it is not clear how this will change in a warming climate in the future. In this paper, the net ecosystem productivity (NEP) of alpine grasslands in Qinghai province, on the Qinghai-Tibetan Plateau, was predicted for the period from 2010 to 2099. Trends and stability were analyzed under two climate scenarios, Representative Concentration Pathway 4.5 (RCP4.5) and 8.5 (RCP8.5) representing the lower and higher emission scenarios for greenhouse gases. The results suggest that grasslands will continue to contribute as a carbon sink, with a positive NEP through this century. Almost the same magnitude (38 Tg C a-1, 1 T g = 1012 g) of contribution was projected under both scenarios. Grasslands are projected to be the major contributor to NEP in Qinghai province, with more than 89% of NEP in the future. The carbon sink function will increase over more than 69% of the grasslands and peak around 2069 (RCP4.5) or 2066 (RCP8.5). Then the carbon sink function will begin to decrease and it will decrease more quickly and become more variable under the RCP8.5 than the RCP4.5. The impacts of temperature and precipitation changes were analyzed and NEP was found to be more sensitive to temperature than precipitation change. The trend of increasing contribution to NEP is driven by a warming climate, while the stability of NEP is mainly influenced by the precipitation, which results in an upward trend before the peak and a decline due to stresses from limits in available water in a continued warming climate.

AbstractBackgroundAn accurate assessment of the carbon budget is a crucial part of projecting future climate change and its impact on ecosystems. Grasslands foster multiple ecological functions including support for wild animals and livestocks. Herbivores intake forage biomass carbon, then digest and metabolize, and finally retain some carbon. The carbon processes have not been well quantified, resulting in uncertainties in the estimation of regional carbon budgets for grassland ecosystems.MethodsAn animal metabolic carbon flux model was developed for herbivores in the Three‐Rivers Headwaters region of China. The forage intake and metabolic carbon rates were estimated through metabolic body weight and daily digested measures for the main herbivore species.ResultsThe carbon intake was 5.52 Tg C year−1 (45%) from partial aboveground biomass (12.2 Tg C year−1), in which 39.31% was released into the atmosphere by respiration CO2, 43.77% was returned to the ecosystem as feces and urine, and 16.96% was retained in herbivores for population regeneration or for human well‐being.ConclusionsThis study, as the first research on this topic, quantified the carbon flux of herbivores and found livestock accounts for a major part of consumed carbon on grasslands, which is important for understanding regional carbon budgets to mitigate and adapt to climate change over grasslands worldwide.

South Asia, one of the most important food producing regions in the world, is facing a significant threat to food grain production under the influence of extreme high temperatures. Furthermore, the probability of simultaneous trends in extreme precipitation patterns and extreme heat conditions, which can have compounding effects on crops, is a likelihood in South Asia. In this study, we found complex relationships between extreme heat and precipitation patterns, as well as compound effects on major crops (rice and wheat) in South Asia. We also employed event coincidence analysis (ECA) to quantify the likelihood of simultaneous temperature and crop extremes. We used the Enhanced Vegetation Index (EVI) as the primary data to evaluate the distinct responses of major crops to weather extremes. Our results suggest that while the probability of simultaneous extreme events is small, most regions of South Asia (more than half) have experienced extreme events. The regulatory effect of precipitation on heat stress is very unevenly distributed in South Asia. The harm caused by a wet year at high temperature is far greater than that during a dry year, although the probability of a dry year is greater than that of a wet year. For the growing seasons, the highest significant event coincidence rates at a low EVI were found for both high- and low-temperature extremes. The regions that responded positively to EVI at extreme temperatures were mainly concentrated in irrigated farmland, and the regions that responded negatively to EVI at extreme temperatures were mostly in the mountains and other high-altitude regions. Implications can guide crop adaptation interventions in response to these climate influences.

Significance StatementNatural resource planners face the challenging task of sustaining the diverse range of human-nature relationships supported by mountain systems. Planners of the Flathead Wild and Scenic River system cannot reasonably consider and communicate each individual human-nature relationship in the planning process. We present a social science approach that facilitates public engagement by having members of the interested public prioritize human and ecological meanings and services. Statistical analysis distills the diverse range of human-nature relationships into a limited number to be considered by river planners. Six typified human-nature relationships are explored, and through an understanding of synergies and tensions, planners gain knowledge to support both decision-making and communication for sustaining the integrated mountain system.

The application of scientifically rigorous public engagement approaches is lacking. In this context, we present a "social vulnerability protocol" which has now been applied in several broad-scale planning efforts. The protocol aims to understand the multitude of relationships that people have with public land through a prioritization of ecosystem services and a selection of relevant drivers of change. The protocol is analytically rigorous and readily interpretable, and is clearly tied to the planning objectives of knowledge co-production, tradeoff analysis, and understanding how various threats may impact social well-being. In the context of the Gila National Forest Plan revision, comparisons between the perspectives of the public and those of the local land management agency show a diversity of stakeholder values and human-nature relationships. We believe this approach contributes to more inclusive decision-making, strengthens public understanding of the complexities involved, and builds trust through transparent and explicit acknowledgement of diverse perspectives.

Promoting sustainability of ecosystems and economic development is a dual national objective in China, as well as one of the sustainable development goals (SDGs) of the United Nations. The Three-River Headwaters Region, where a National Park initiative has been initiated in the pastoral region of the Qinghai-Tibetan Plateau, is one of the key pilot projects in China with sustainability targets for 2025 and 2035. This paper assesses the possibility of achieving established targets for the proportion of cultivated to available grassland. These targets consider both ecosystem protection and herders’ livelihoods. An income simulation model was first developed to estimate the percentage of cultivated grassland area necessary from the natural grasslands to achieve the target income. The model was developed using income and livestock data from the annual yearbook for 2018, then applied to estimate conditions for three counties in the eastern region. Presently the rangelands are seriously overgrazed with income just reaching above the poverty level. If livestock were decreased to a theoretical carrying capacity level, income would decrease to lower than the poverty level, even considering a livestock feeding system to achieve higher production levels. Under these circumstances, in order to reach income targets in 2025, one option centered on income production from livestock requires 5% of grasslands to be cultivated to produce forage for livestock. However, achieving income targets in 2035 will become very difficult because the needed proportion was estimated to increase to 14%. An alternative was to transport extra forage from the agriculture region of eastern Qinghai province. The local government should consider these two options to improve herders’ income along with maintaining the traditional nomadic culture and sustainable ecosystems. The approach used to develop and apply this model could be applied to predict income changes accompanying future climate scenarios and to propose policies aimed at sustainability of ecosystems and economies for grasslands worldwide.

Widespread concern about ecological degradation has prompted development of concepts and exploration of methods to quantify ecological quality with the aim of measuring ecosystem changes to contribute to future policy-making. This paper proposes a conceptual framework for ecological quality measurement based on current ecosystem functions and biodiverse habitat, compared with pixel-scale historical baselines. The framework was applied to evaluate the changes and driving factors of ecological quality for Chinese terrestrial ecosystems through remote sensing-based and ecosystem process modeled data at 1 km spatial resolution from 2000 to 2018. The results demonstrated the ecological quality index (EQI) had a very different spatial pattern based upon vegetation distribution. An upward trend in EQI was found over most areas, and variability of 46.95% in EQI can be explained well by change in climate, with an additional 10.64% explained by changing human activities, quantified by population density. This study demonstrated a practical and objective approach for quantifying and assessing ecological quality, which has application potential in ecosystem assessments on scales from local to region and nation, yet would provide a new scientific concept and paradigm for macro ecosystems management and decision-making by governments.

Monitoring and evaluating ecological quality and changes are crucial for policy formulation to guide ecosystem management and socioeconomic sustainable development. However, evaluation of ecological quality is still very challenging due to difficulties in determination of its associated indicators and weights. This paper proposes supporting, providing and regulating ecosystems services-based indicators to describe ecological quality, and applies a Projection Pursuit Model to eliminate redundant indicators and objectively determine weights for an ecological quality index (EQI) on a regional scale. Taking Jiangxi Province, China, as a demonstration area, the data for indicator measures were retrieved from satellite remote sensing and ecosystem modelling with a spatial resolution of 1 km for the three years 2005, 2010 and 2015. The results suggest that Normalized Difference Vegetation Index (NDVI) and water use efficiency (WUE) should be weighed higher and leaf area index (LAI) and Bowen ratio should be weighed lowest in the calculation of an EQI for Jiangxi Province. For 2015, the regional EQI was calculated to be 55.32 on a scale from 0 as the worst to 100 as the best, with higher values ascribed to the hills and mountains and the lower values existing near urban areas. The EQI increased from 52.26 in 2005 to 55.32 in 2015 with an increased area of good-and-above grade from 25.47% to 36.8% for the whole province. The changes in EQI could be attributed to a warmer and wetter climate trend playing a positive dominant effect, while urbanization and afforestation have negative and positive effects, respectively. This study demonstrates that it is feasible to evaluate ecological quality based on a comprehensive set of indicators and PPM-based weight determination, which could be further applied in regular ecological quality monitoring and evaluation on the regional, or even the national scale.

The complexities of English land law are primarily the result of the doctrine of estates. To all intents and purposes the doctrine of estates was abolished by the 1925 legislation. The review points raise issues of great importance for understanding law and for law reform. The key to legal development and law reform thus lies in the nature of the sources of law, and how these are perceived. The fact is obvious, but the equally obvious conclusion is not usually drawn: serious law reform should begin with a critical look at the law-making machinery. Contrary to appearances, this is not a paper on the Rule against Perpetuities, but on law reform and legal development. Historically, in the western legal tradition, legislation has been uncommon. This is true, for example, of ancient Rome and England until the 19th century. Theoretically, legislation should be a satisfactory way to make law.