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Climate change has profoundly affected the synchrony of tree growth at multiple scales, thereby altering the structure and function of forest ecosystems. The Asian boreal forests extend southward to the Greater Khingan Range in northeast China. Given the ecological importance and susceptibility to climate change, the impacts of warming on this marginal forest community have been extensively investigated. Nonetheless, how tree growth synchrony changes across this region remains less understood. Focusing on this knowledge gap, we compiled a contiguously-distributed tree-ring network, containing 18 sampling populations and 475 individual larch trees, to explore the changes in multiple-scale growth synchrony across this region. We found increasing growth synchrony at both the individual and population levels over the past decades. The increasing trend of the regional inter-population growth synchrony was well in line with the increasing temperature and PDSI. Furthermore, 11 of the 18 sampling populations showed significant increases in their intra-population growth synchrony. We further associated the sliding intra-population growth synchrony with local climates. Intra-population growth synchrony of 13 and 11 sampling populations were significantly positively correlated with local temperature, and negatively correlated with local PDSI, respectively, demonstrating the driving role of warming-induced drought on growth synchrony. The linear regression model quantifying this relationship suggested that an increase of 1 °C in annual mean temperature would drive the intra-population growth synchrony to increase by 0.047. As warming trends in the study area are projected to continue over this century, our study warns of the further consequences of the increasing growth synchrony may have on the functioning, resilience, and persistence of forests.
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Cambio Climático , Árboles , China , Árboles/crecimiento & desarrollo , Taiga , Bosques , Calentamiento Global , Temperatura , EcosistemaRESUMEN
The rapid transition of agricultural systems substantially affects residential and industrial land use systems in rural areas, often generating spatiotemporal trade-offs between residential and industrial functions and producing considerable ecological impacts, which has thus far not been well understood. We conduct an indicator-based assessment of transitioning agriculture systems, and then links the transitioning agricultural systems to trade-offs between residential and industrial functions from 2005 to 2020 by using a case study-the metropolitan suburbs of Beijing, China. Also, the associated ecological impacts of the trade-offs are characterized based on the calculation of the ecological quality index (EQI) and ecological contribution rate. The results show that trade-offs between residential and industrial functions in the metropolitan suburbs have gradually adapted to the different agricultural systems in transition, which can be characterized by increasing industrial function as well as declining residential function, together with the diversification of land use into a mixed pattern. Additionally, along with the transitioning process comes a U shape of the ecological quality curve, which indicates that relentless industrial sprawl into regions where the agricultural system has a low capacity for technology, as well as decay in rural areas attributed to a rural exodus and industrial decline in semi-subsistence agricultural areas, even cause ecological degradation. In general, trade-offs between residential and industrial functions (especially for the non-agricultural production function) in rural areas could partially and temporally generate unfavorable ecological impacts, but it seems to be a favorable phenomenon to promote ecological quality in the long term. Therefore, to achieve rural sustainable planning, it is necessary for land use management to observe the trade-offs between residential and industrial functions while avoiding negative impacts, such as low-density land use patterns, disordered land use functions, and eco-environmental deterioration. Such effective strategies can contribute to the feasible implementation of policies aiming to achieve the compatible development of liveable residences, highly efficient industrial production, and eco-friendly operations in rural areas.
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Agricultura , China , Industrias , Conservación de los Recursos Naturales , Población Rural , EcologíaRESUMEN
Agricultural machinery is effective in improving food production and labor productivity, but it also raises environmental concerns. The impacts of agricultural machinery on the green total factor productivity (GTFP) of grain in China are still under debate in the scientific literature. This study proposed an integrated framework for confronting this issue. The findings suggest that both agricultural mechanization and the GTFP of grain demonstrate a consistent upward trend with moderate fluctuations between 2001 and 2019. By expanding the spatial pattern, there is a positive spatial correlation between them. In addition, we compared the results in three grain functional areas by using the spatial Durbin model (SDM). There were significantly positive spatial spillover effects in major grain-producing areas, which were attributed to the trans-regional operation of agricultural machinery and its carbon reduction effects on neighboring provinces. Notably, the direct effects in major grain-marketing areas and producing-marketing balance areas were significantly positive because agricultural machinery has played a critical role in filling the gap in local labor shortages in grain production. Accordingly, adaptive strategies including building the "Internet + agricultural machinery operation" platform, implementing the land consolidation suitable for machinery, and developing low-carbon agricultural machinery should be fully considered by Chinese policy-makers to promote mechanized agriculture and a low-carbon economy. The findings of this study can help us better understand the role of agricultural machinery in improving green grain productivity in China and thus have significance for the modern and green transformation of agricultural production systems.
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Larch, a widely distributed tree in boreal Eurasia, is experiencing rapid warming across much of its distribution. A comprehensive assessment of growth on warming is needed to comprehend the potential impact of climate change. Most studies, relying on rigid calendar-based temperature series, have detected monotonic responses at the margins of boreal Eurasia, but not across the region. Here, we developed a method for constructing temporally flexible and physiologically relevant temperature series to reassess growth-temperature relations of larch across boreal Eurasia. Our method appears more effective in assessing the impact of warming on growth than previous methods. Our approach indicates widespread and spatially heterogeneous growth-temperature responses that are driven by local climate. Models quantifying these results project that the negative responses of growth to temperature will spread northward and upward throughout this century. If true, the risks of warming to boreal Eurasia could be more widespread than conveyed from previous works.
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Larix , Larix/fisiología , Taiga , Árboles , Cambio Climático , Temperatura , BosquesRESUMEN
The harmonious coexistence of man and nature is a universally recognized standard to test the rational utilization of multifunctional territorial space, and the planning of territorial space adapted to nature is a scientific guide to balance ecological protection and human development. This study focuses on the inevitable relationship between the scale, function and pattern of territorial space utilization (TSU), and puts forward a process research framework of "background evaluation-advantage comparison-optimization conduction". Based on the evaluation of resource and environment suitability, this paper determines the scale of multifunctional territorial space through the potential conflict identification model of TSU. The location entropy method is used to identify the advantageous functions of the county level, and the matching characteristics of the research results and the current situation are obtained by comparing them with the current plan. Finally, from the county functional zoning to the regional TSU pattern, the corresponding optimization conduction path is designed to form a new development and protection pattern. The empirical results of research area show that: (1) The study area is suitable for urban construction and agricultural production as a whole. The ecological protection is mainly at the general important level, and there is a moderate potential conflict between the development and protection of territorial space. The space scale of urban construction, agricultural production and ecological protection are accounted for 8.77%, 78.71% and 12.52%, respectively. (2) The advantageous function of TSU in county-level administrative units is dominated by single advantageous function, and the number of composite advantageous functions is generally small. The advantageous functional types determined by this research have a high matching with the current plan. (3) Based on the analysis of the scale structure and functional use of territorial space, this paper defines the ecological space that should be strictly protected and the agricultural and urban space that should be moderately developed for production and construction, and sets up elastic development areas. Finally, a strategic pattern of "one corridor, two screens, three circles and four zones" is conducive to the realization of the beautiful vision of the unification of protection and development.
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Planificación de Ciudades , Conservación de los Recursos Naturales , Humanos , Conservación de los Recursos Naturales/métodos , Planificación de Ciudades/métodos , Agricultura , Adaptación Fisiológica , China , Ecosistema , CiudadesRESUMEN
Identifying available farmland suitable for agricultural machinery is the most promising way of optimizing agricultural production and increasing agricultural mechanization. Farmland consolidation suitable for agricultural machinery (FCAM) is implemented as an effective tool for increasing sustainable production and mechanized agriculture. By using the machine learning approach, this study assesses the suitability of farmland for agricultural machinery in land consolidation schemes based on four parameters, i.e., natural resource endowment, accessibility of agricultural machinery, socioeconomic level, and ecological limitations. And based on "suitability" and "potential improvement in farmland productivity", we classified land into four zones: the priority consolidation zone, the moderate consolidation zone, the comprehensive consolidation zone, and the reserve consolidation zone. The results showed that most of the farmland (76.41%) was either basically or moderately suitable for FCAM. Although slope was often an indicator that land was suitable for agricultural machinery, other factors, such as the inferior accessibility of tractor roads, continuous depopulation, and ecological fragility, contributed greatly to reducing the overall suitability of land for FCAM. Moreover, it was estimated that the potential productivity of farmland would be increased by 720.8 kg/ha if FCAM were implemented. Four zones constituted a useful basis for determining the implementation sequence and differentiating strategies for FCAM schemes. Consequently, this zoning has been an effective solution for implementing FCAM schemes. However, the successful implementation of FCAM schemes, and the achievement a modern and sustainable agriculture system, will require some additional strategies, such as strengthening farmland ecosystem protection and promoting R&D into agricultural machinery suitable for hilly terrain, as well as more financial support.
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The characteristic style of rural houses is an important manifestation of the historical and cultural values of rural areas and is the key focus of the implementation of the strategy for the construction of beautiful China and the revitalization of rural areas. Taking 17 villages in the Rongcheng of Shandong as an example, this article integrated multidimensional data, including geospatial data, survey data and socio-economic data, and constructed a suitable index system to evaluate the characteristic style of coastal rural houses in 2018 and put forward the characteristic style regionalization of coastal rural houses. The results show that the characteristic style of coastal rural houses can be measured by the overall village environment, coastal architectural value and traditional folk culture, among which the coastal architectural value is the most critical. Two villages scored over 60 points in the comprehensive evaluation, namely the Dongchu Island village and Dazhuang Xujia Community. Different dominant characteristic styles of rural houses were identified according to single-factor evaluation. Based on the evaluation results and factors such as location, nature, social economy and the status quo of protection and development management, characteristic styles of rural houses in the research area can be divided into four continuous areas: historical and cultural characteristics, folk customs and industrial development characteristics, natural scenery characteristics and folk customs characteristics. Combined with regional positioning and development planning, the construction direction of different regional types was defined, and then the protection and improvement measures of rural residential features were put forward. This study not only provides a certain basis for the evaluation, construction and protection of the characteristic features of coastal rural dwellings in Rongcheng City but also provides guidance for the implementation of rural construction planning.
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Cultura , Población Rural , Humanos , China , Ciudades , Características CulturalesRESUMEN
By applying an integrated framework, we developed a new way to quantify the multifunctionality of rural residential land: analyzing the reciprocal relationships between the structure and function of land use, as well as identifying the demand of rural sustainability for residential land functions. In the assessment of the rural residential land functions from the supply and demand perspectives by establishing an indicators system, the results show that there are five substantial functions of rural residential land, i.e., residential, public service, industrial, commercial and ecological function, and a potential function. Unbalanced development patterns between function supply and demand are clearly observed at multilevel: at the regional level, demand exceeding supply refers to the public service, commercial, and ecological function, especially for ecological function; at the town level, the spatial pattern of the difference is closely linked with topographic features; the inferior and complex topographic condition always is associated with inadequate function supply. Strategies based on the arrangements of rural residential land use structure, including function conversion and function enhancement, have been adopted to balance the supply and demand of land functions. Together, alternative strategies (e.g., industrial allocation, population introduction, and location choices) also need to be recognized by policymakers to achieve rural sustainable development.
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Agricultura , Ecología , Características de la Residencia , Ciudades , Conservación de los Recursos Naturales , Vivienda , Planificación SocialRESUMEN
Rural settlements transition (RST) is one of the most significant indices for understanding the phenomena of rural reconstruction and urban-rural transformation in China. However, a systematic overview of RST is missing, and there is a lack of evidence regarding its characteristics from the internal structure perspectives. In this paper, we systematically explore the RST regarding spatio-temporal change characteristics of internal structure, patterns and impacts on rural environment and development by using practical survey internal land-use data from 2005 to 2015. The results show that the temporal change characteristics of the internal structure of rural settlements demonstrate a tendency for housing land to decrease and other land-use types to increase. The spatial change characteristics reveal that the structure inclines to more complexity and diversity from an exurban area to an urban-rural fringe area. Based on this finding, we identify that rapid development of rural industrialization, more agglomerate and effective industrial land-use, and improved public infrastructure construction are the general RST patterns. Spatially, there exists a physical decay pattern in the exurban area, thereby resulting in the hollowing-out of rural industries and of the population. In addition, the extensive and disorderly pattern in the suburban area causes low efficiency output and serious environmental pollution. The RST pattern in the urban hinterland promoted the "men-environment" compatible development. The study concludes that regional differentiation in patterns and impacts are significant in the process of RST. Future adaptive strategies for rural settlements adjustment should be conducted according to regional characteristics, including socio-economic status, physical geography condition and economic location to improve the rural environmental sustainability.