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This special issue is the first systematic introduction to the progress of landsenses ecology and its applications since its formation in 2016. As a people-oriented, science-technology-base...

Delineation of individual deciduous trees with Light Detection and Ranging (LiDAR) data has long been sought for accurate forest inventory in temperate forests. Previous attempts mainly focused on ...

Excessive logging in China is the major cause of poor forest quality, degraded ecosystem functions, and near exhaustion of harvestable resources of the country’s natural forests. An overall extended moratorium on logging in the country’s natural forests has been launched since 2015, which is a suggested method for the gradual recovery of the structure and functions of these forests. However, the main purpose to manage the degraded natural forest after the moratorium remains not yet clear. This paper firstly reviews China’s natural forest management history and clarifies the causes accounting for natural status duo, and then analyses changes in domestic natural forests and timber supply and demand in China, identifies the problems related to the sustainable operation of natural forests, especially those requiring immediate attention. Results shows that as the demand for timber continues to increase rapidly, China will experience a severe imbalance between timber supply and demand. In the long run, timber imports alone cannot meet increasing domestic demands, natural forests remain the primary source of wood products. Many issues concerning management practices and operations technology remain, including ineffective overall spatial zoning, rough operation and management of timber forests, and financial difficulties in forested areas. All of these issues have prevented natural forests from realizing both their ecological functions and timber resource potential. A moratorium on timber harvesting would offer a valuable opportunity for natural forests to recover from decades of excessive logging, as well as an exciting chance to develop sustainable operational practices, ecological functions promotion and relevant technologies. In summary, strategies for the sustainable management and ecosystem services promotion of natural forests during a harvesting moratorium are suggested.

Accurate quantification of forest aboveground biomass (AGB) is the foundation to the responses of diverse forest ecosystems to the changing climate. Lidar-based statistical models have been used to accurately estimate AGB in large spatial extents, especially in boreal and temperate softwood forest ecosystems. However, the few available models for temperate hardwood and hardwood-dominated mixed forests are low in accuracy due both to the deliquescent growth form of hardwood trees and the strong site-to-site variations in height-diameter relationship. In this study, we established multiplicative nonlinear regression models that incorporated both lidar-derived metrics and soil-based site productivity classes (high and low productivity sites) to estimate aboveground biomass in temperate hardwood forests. The final optimized model had high accuracy (R 2 = 0.81; RMSE = 45.5 Mg ha − 1 ) with reliable performance in ABG estimation by integrating relative height metrics at 75 and 70 percentiles (RH75 and RH70), canopy coverage and site productivity class. An optimized model that included an index of site productivity explained 14% more variance than the best-fit model without the term. Moreover, the relationship between AGB and lidar-based metrics was nonlinear on low productivity sites and nearly linear on high productivity sites, further indicating the importance of including direct or indirect measures of site productivity in lidar-based biomass models, particularly for those applied to temperate hardwood forests. Our new lidar-based model provides a potential framework to integrate lidar-based structural information and soil-based site productivity to improve AGB estimation in temperate hardwood forests.

The landscape ecological risk (LER) in Xiamen City, China, from 1990 to 2030 was studied using an urban land use and land cover change (LUCC) model and LER analysis. The LUCC model was used to pred...

Conservation programs that incentivize the increased provision of ecosystem services on private lands have become common policy instruments. The forgone revenues implied by these programs and the ecosystem services benefits they provide might be spatially heterogeneous. However, such programs are not always spatially targeted to maximize the return on conservation investment (ROI). Here, we use an integrated spatial, ecological-economic modeling approach to assess the ROI for water purification in the case of the Indiana Classified Forest and Wildlands (CFW) Program, United States. We compared the ROI of the existing non-spatially targeted CFW expansion to hypothetical, spatially targeted expansion scenarios in the White River Basin of Indiana. First, we projected nutrient retention services to increase greatly under the hypothetical spatially targeted scenarios and modestly in the non-spatially targeted, baseline case. Second, our results revealed the inclusion of conservation costs could substantially change the conservation priorities. In particular, private forestlands in subwatersheds with average conservation benefits and low conservation costs, as opposed to those with high conservation benefits and high conservation costs, would be prioritized for the CFW program, based on their positive ROIs. Third, we found that the benefits from the single ecosystem service of nutrient retention could exceed the conservation costs of the tax deductions and forgone alternatives (i.e., agriculture) if the program was targeted to contaminated watersheds. This research contributes to the integration of forest economics, forest conservation, and forest ecology to assess the effectiveness of forest conservation programs such as the CFW. It also informs citizens and governments on the benefits and costs of potential targeted increased enrollments of the CFW program in Indiana.

Rapid assessment of natural disasters is essential for disaster analysis and spatially explicit strategic decisions of post-disaster reconstruction but requires timely available data. The recent daily data of the National Polar-Orbiting Partnership Visible Infrared Imaging Radiometer Suite (NPP-VIIRS) day/night band (DNB) provide new opportunities to detect and evaluate natural disasters. Here, we introduce an application of NPP-VIIRS DNB daily data for rapidly assessing the damage of a severe typhoon that struck the urban agglomerations along the western Taiwan Straits in China. Our research explored the methods of rapid identification and extraction of the areas based on changes in nighttime light (NTL) after the typhoon disaster by using a statistical radiation-normalization method. We analyzed the correlations of NTL image derivatives with human population, population density, and gross domestic product (GDP). The strong correlations were found between NTL image light density and population density (R2 = 0.83) and between the total nighttime light intensity and GDP (R2 = 0.96) at the prefecture level. In addition, we examined the interrelationships between changes in NTL images and the areas affected by the typhoon and proposed a method to predict the affected population. Finally, the affected area and the affected population in the study area could be rapidly retrieved based on the proposed remote sensing method. The overall accuracy was 83.2% for the detection of the affected population after disaster and the recovery rate of the affected area was 86.9% in the third week after the typhoon. This research demonstrates that the NTL image-based change detection method is simple and effective, and further explains that the NPP-VIIRS DNB daily data are useful for rapidly assessing affected areas and affected populations after typhoon disasters, and for timely quantifying the degree of recovery at a large spatial scale.

The planning and construction of large-scale coal-fired power plants are important components of China’s future energy development strategy in response to global environmental problems, as proposed in China’s Twelfth Five-Year Plan for National Economic and Social Development. With the rapid socio-economic development, research and assessments of ecological risks of large-scale human activities have drawn increasing attention. As large-scale coal-fired power plant are more concentrated in the northern arid and semi-arid areas of China, where the environment is fragile, objective assessments of the ecological risks at large-scale coal power bases are important for ensuring the sustainable development of coal bases and guaranteeing the normal and orderly life of surrounding residents. Ecological sensitivity evaluations reflect the degree of changes in the natural environment due to human disturbance, and explain the possibility of ecological assessments in the region. Based on comprehensive evaluati...

Forest wildfires pose significant and growing threats to human safety, wildlife habitat, regional economies and global climate change. It is crucial that forest fires be subject to timely and accurate monitoring by forest fire managers and other stake-holders. Measurement by spaceborne equipment has become a practical and appealing method to monitor the occurrence and development of forest wildfires. Here we present an overview of the principles and case studies of forest fire monitoring (FFM) with satellite- and drone-mounted infrared remote sensing (IRRS). This review includes four types of FFM-relevant IRRS algorithms: bi-spectral methods, fixed threshold methods, spatial contextual methods, and multi-temporal methods. The spatial contextual methods are presented in detail since they can be applied easily with commonly available satellite IRRS data, including MODIS, VIIRS, and Landsat 8 OLI. This review also evaluates typical cases of FFM using NOAA-AVHRR, EOS-MODIS, S-NPP VIIRS, Landsat 8 OLI, MSG-SEVIRI, and drone infrared data. To better implement IRRS applications in FFM, it is important to develop accurate forest masks, carry out systematic comparative studies of various forest fire detection systems (known as forest fire products), and improve methods for assessing the accuracy of forest fire detection. Medium-resolution IRRS data are effective for landscape-scale FFM, and the VIIRS 375 m contextual algorithm and RST-FIRES algorithm are helpful for closely tracking forest fires (including small and short-lived fires) and forest-fire early warning.

Urban ecological risk (UER) caused by rapid urbanization means potential threat to urban ecosystem structure, pattern and services. The scales of ecological risk assessment (ERA) have been expanded from individual organisms to watersheds and regions. The types of stressor range from chemical to physical, biological and natural events. However, the application of ERA in urban ecosystems is relatively new. Here, we summarize the progress of urban ERA and propose an explicit framework to illumine future ERA based on UER identification, analysis, characterization, modeling, projection and early warning and management. The summary includes six urban ERA-relevant methods: weight-of-evidence (WoE), procedure for ecological tiered assessment of risks (PETAR), relative risk model (RRM), multimedia, multi-pathway, multi-receptor risk assessment (3MRA), landscape analysis and ecological models. Furthermore, we review critical cases of urban ERA in landscape ecology, soil, air, water and solid waste. Based on...

Features relevant to a thematic class, that is, class-specific features are beneficial to thematic information extraction. However, existing class-specific feature selection methods require abundant labelled samples, while sample labelling is always labour intensive and time consuming. Therefore, it is necessary to select class-specific features with insufficient labelled objects. In this paper, we raise this problem as semi-supervised class-specific feature selection and propose a new two-stage method. First, a weight matrix fully integrates local geometrical structure and discriminative information. Second, the weight matrix is incorporated into a -norm minimization optimization problem of data reconstruction to objectively measure the effectiveness of features for a thematic class. Different from the explicit binarization in the label vector, the new method only implicitly employs binarization in the weight matrix. With area under receiver-operating characteristic curve, class-specific features...

The utilization of urban green space (UGS) in a city contributes to people’s mental and physical health. Information on the perceptions and attitudes of people from landscape evaluation and preference studies serves as an important scientific basis for the planning and management of UGS. This study used eye tracking and an online questionnaire to investigate the association between the proportions of different landscape elements and people’s evaluation of UGS attractiveness. Experiments were conducted by using photographs taken in Shanghai with varying green appearance percentages (GPs) and different types of landscape elements (trees, water, artificial hardscapes, etc.). The results showed that the influence of GP on landscape attractiveness was greater when its level was below 45 % than when above 48 %. Landscape elements, including trees, pedestrians and visually dominant elements (overpasses, sign boards, seats and other elements that may attract an observer’s attention), affected participants’ evaluations. People who paid more attention to trees and pedestrians than visually dominant elements were more likely to give a higher evaluation. The reflection of greenery on a water surface enhanced residents’ perception to GP. Hardscape divided the attraction of the vegetation and lowered the evaluation of the landscape. This study demonstrates a meaningful attempt to use eye tracking in combination with online questionnaires for urban green space. The confined data sources are useful to reveal human’s perception of landscapes, and a clearer understanding of residents’ preference to landscape elements can be obtained in the decision making of UGS planning and management.

Intense human activities and drastic land use changes in rapidly urbanized areas may cause serious water quality degradation. In this study, we explored the effects of land use on water quality from a landscape perspective. We took a rapidly urbanized area in Hangzhou City, China, as a case study, and collected stream water quality data and algae biomass in a field campaign. The results showed that built-up lands had negative effects on water quality and were the primary cause of stream water pollution. The concentration of total phosphorus significantly correlated with the areas of residential, industrial, road, and urban greenspace, and the concentration of chlorophyll a also significantly correlated with the areas of these land uses, except residential land. At a landscape level, the correlation analysis showed that the landscape indices, e.g., dominance, shape complexity, fragmentation, aggregation, and diversity, all had significant correlations with water quality parameters. From the perspective of land use, the redundancy analysis results showed that the percentages of variation in water quality explained by the built-up, forest and wetland, cropland, and bareland decreased in turn. The spatial composition of the built-up lands was the main factor causing stream water pollution, while the shape complexities of the forest and wetland patches were negatively correlated with stream water pollution.

The downstream of the world’s largest Three Gorges Dam (TGD) along Yangtze River (1560 km) hosts numerous mid-channel bars (MCBs). The morphodynamics of these MCBs are crucial to the river’s hydrological processing, local ecological functioning, and socioeconomic development. However, a systematic understanding of such dynamics and their linkages to the TGD across the entire downstream reach remain largely unknown. Using Landsat archive images and a thematic extracting scheme, the work presents comprehensive monitoring of MCB dynamics in terms of number, area, and shape, in the downstream of the TGD during 1985–2018. Total 140 MCBs were extracted and grouped into four types to represent small size (2), middle size (2 km2–7 km2), large size (7 km2–33 km2) and extra-large size (> 33 km2) MCBs, respectively. Most of the MCBs in terms of number (70 %) and total area (91 %) were concentrated in the lower reach (Hankou to Estuary). The number of small size MCBs decreased after TGD closure and most of such decreasing events happened in the lower reach. Although all four types of MCBs showed overall increasing trends in area, small MCBs had smaller rate and received more influence by the TGD operation than the large MCBs. Small size MCBs tended to become relatively shorter and wider whereas the others became slimmer after TGD operation. Impacts from the TGD operation could decrease along with the increasing distance from TGD to Hankou (for shape dynamics) or to Jiujiang (for area dynamics). The quantified longitudinal and temporal dynamics of MCBs across the whole downstream of the TGD provides a crucial monitoring basis for continuous investigations of changing mechanisms in the morphology of the Yangtze River system.

In recent years, intensified industrialization and rapid urbanization have accelerated the accumulation of trace metals in topsoils of the Golden Triangle of Southern Fujian Province in China. Trace metals can cause adverse impacts on ecosystems and human health. In order to assess the ecological and human health risks of trace metals in the Golden Triangle region and to determine the distribution and degree of pollution of trace metals, 456 soil samples were collected from 28 districts. The concentrations of six metals (As, Cr, Cu, Ni, Pb, and Zn) were analyzed to assess ecological risk using the geoaccumulation index (Igeo) and the potential ecological risk index (RI). The United States Environmental Protection Agency (USEPA) model was applied to calculate health risk. The average soil concentrations of the six elements are ranked as follows: As &lt, Ni &lt, Cu &lt, Cr &lt, Pb &lt, Zn. Inverse distance weighting (IDW) interpolation maps showed that Cr, Cu, Ni, and Zn are enriched in the soils of developed areas, while As and Pb are enriched in the soils of undeveloped areas. The Igeo showed that the levels of metals in most soil samples are below polluting levels. Similarly, RI values indicated that trace metals pose low potential ecological risk in the region&rsquo, s soils. The Hazard Quotient (HQ) ranked the mean total noncarcinogenic risk of the six metals, for both children and adults, as follows: As &gt, Pb &gt, Cr &gt, Ni &gt, Cu &gt, Zn. The mean carcinogenic risk (CR) of the metals in the region&rsquo, s soils are ranked as follows: Cr &gt, As &gt, Ni. The Hazard Index (HI) values indicated that 3.7% of soils contained unsafe levels of toxic metals for children and total carcinogenic risk (TCR) values indicated that 23.3% of soils contained unsafe levels, indicating that children are facing both noncarcinogenic and carcinogenic risks from trace metals. Principal component analysis (PCA) and matrix cluster analysis were used to identify pollution sources and classified trace metals and soil samples into two and five groups, respectively. The five groups represented the effects of different land use types, including agricultural area, residential and public area, industrial area, forest, and industrial area and roadside, based on the contents of trace metals in soils. Industrial, agricultural and traffic activities attribute to the enrichment of Cr, Cu, Ni, Pb, and Zn in the region&rsquo, s soils. Moreover, the accumulation of As and Pb are also attributed to atmospheric deposition. These results can contribute to a better understanding of pollution, ecological risks, and human health risks from trace metals on large regional scales like the Golden Triangle of Southern Fujian Province.

Intensifying urbanization and rapid population growth in Fujian Province, China, has caused pollution of air and water resources; this has adversely impacted ecosystems and human health. China has recently begun pursuing a massive infrastructure and economic development strategy called the Belt and Road Initiative, which could potentially cause further environmental damage. Evaluations of ecosystem health are therefore a first step towards identifying the potential impacts from the development and planning sustainable development strategies in the Golden Triangle of Southern Fujian. To this end, our study analyzed landscape patterns and evaluated ecosystem health in this region. We used an index system method to develop a pressure–state–response (PSR) model for assessing the region’s ecosystem health. We found that: (1) the landscape type with the greatest area in the study region is cultivated land and there were no areas that were undisturbed by human activity; (2) the overall ecological health of the region is good, but there is distinct variation across the region. This study incorporates the landscape pattern into an evaluation of ecosystem health. Using counties as evaluation units, we provide a general evaluation index for this scale. The methods reported here can be used in complex ecological environments to inform sustainable management decisions.

With the emerging problems of air pollution and urban heat island associated with urbanization, urban microclimatic spatial planning was attended unprecedentedly. Microclimatic spatial planning is proposed within the framework of landsenses ecology and its aim is to harmoniously integrate human with nature and specifically to improve the microclimate comfortable sensation for people from wind speed, temperature, humidity, etc. In this paper, we analyzed the current spatial pattern of the microclimate in Xianghe Segment of China’s Grand Canal (XSCGC) based on meteorological data, and a computational fluid dynamics (CFD) simulation of human comfort and microclimate expandability. Finally, spatial planning recommendations for XSCGC were proposed to suppress northeasterly winds and protect southwesterly winds, which helped divide the planning area into four functional land-use types to improve the livability and security of microclimate, including microclimate regulatory areas, development core areas,...

This paper proposes the concepts and associated contents of landsenses ecology and mix-marching data, and explains the roles of the meliorization model and Internet of Things (IoT) in the landsenses ecology-based land-use planning, construction and management. It also analyses the importance and application approaches of mix-marching data. In the current situation of rapid social-economic, scientific, and technological development, there exists an urgent need for us to further study landsenses ecology and its applications.

The presence of shadows in optical satellite images limits the application of remote-sensing technology. It is important to restore shadow radiance information for improving information extraction from remote-sensing images. Several shadow-restoration methods have been developed using complex statistical relationships between shadowed areas and their nearby sunlit areas. In this study, a simple shadow-restoration approach was proposed based on the surface reflectance equality relationship RER under the assumption that the surface reflectance of a feature in the shadowed area is equal to that of the same feature in the nearby sunlit area. This approach reduces the number of parameters, thus reducing the error propagated by the uncertainties of extra parameters. The new RER method was tested with three multispectral images with different shadow features. By comparing RER with the widely used mean and variance transformation, the RER was shown to be capable of restoring the image colours, texture, tone, and brightness of the shadowed areas to a visually satisfactory level. Quantitative analysis suggests that RER can help to restore the reflectance of shadow features accurately and has robust performance for a variety of land-surface types. Moreover, RER can be effectively used to restore the spectral shape information of shadow features, which is particularly important when applying RER to the restoration of multispectral imagery for the purpose of image classification.

Drones of various shapes, sizes, and functionalities have emerged over the past few decades, and their civilian applications are becoming increasingly appealing. Flexible, low-cost, and high-resolution remote sensing systems that use drones as platforms are important for filling data gaps and supplementing the capabilities of crewed/manned aircraft and satellite remote sensing systems. Here, we refer to this growing remote sensing initiative as drone remote sensing and explain its unique advantages in forestry research and practices. Furthermore, we summarize the various approaches of drone remote sensing to surveying forests, mapping canopy gaps, measuring forest canopy height, tracking forest wildfires, and supporting intensive forest management. The benefits of drone remote sensing include low material and operational costs, flexible control of spatial and temporal resolution, high-intensity data collection, and the absence of risk to crews. The current forestry applications of drone remote sensing are still at an experimental stage, but they are expected to expand rapidly. To better guide the development of drone remote sensing for sustainable forestry, it is important to systematically and continuously conduct comparative studies to determine the appropriate drone remote sensing technologies for various forest conditions and/or forestry applications.

Many ecosystems extend across national or political boundaries. The consistent and effective protection of these ecosystems in transboundary areas (ETAs) is an important global research focus. Previous research on the protection of such areas can be categorized into seven themes: 1) ecological conservation of a single ETA; 2) investigation of the effects of a single conservation measure on a specific ETA; 3) determination of species-level effects due to ETA conservation; 4) comparison of the same protection measures between different ETAs; 5) introduction of a single conservation measure to a specific ETA; 6) understanding the relationship between conservation and sustainable development; and 7) generalization across multiple ETA conservation cases. The protection of ETAs involves various considerations, including funding support, demand and will for collaboration, community and public participation, historical and cultural factors, political backgrounds, uniqueness of biological resources, formulation of laws and regulations, founding of specialized administrative departments, non-governmental organizations, and fairness. Here, we briefly explain the research themes and considerations related to ETA conservation. The most important finding is that most major research themes do not focus on the challenges of ETA conservation. We use two nature reserves located between China and North Korea as examples to identify specific ways to improve ETA conservation on Changbai Mountains. The efficiency of ETA administration still remains low. The study of ETA conservation should focus on concrete regional information and aim to improve existing measures through the accumulation of experience.

Soil erosion threatens long-term soil fertility and food production in Q’eqchi’ communities native to the Sierra Yalijux and Sierra Sacranix mountain ranges in the central highlands of Guatemala. Environmental factors such as steep topography, erodible soils, and intense precipitation events, combined with land subdivision and reduced fallow periods as a consequence of population growth, contribute to severe erosion and strain soil resources. The preservation of the region's cloud forests hinges on enhancing production of staple crops through agricultural intensification while maintaining soil fertility through implementation of soil conservation measures.

Cloud forest in the Central Highlands of Guatemala provides important ecosystem services for the Q’eqchi’ Maya but has been disappearing at an increasing rate in recent decades. This research documents changes in cloud forest cover, explores some contributing factors to deforestation, and considers forest preservation and food security implications for Q’eqchi’ communities. We used a transdisciplinary framework that synthesized remote sensing/GIS analysis of land cover change, focus group dialogs, and surveys. Expansion of subsistence agriculture is a key proximate cause of cloud forest removal, followed by extraction of fuelwood and larger-scale logging operations. Predisposing environmental factors such as rugged topography, steep slopes, and poor soils contribute to low agricultural productivity that contributes to increased conversion of forest to agricultural land. The key underlying driving forces for deforestation locally are population growth and subdivision of land. Population growth is increasin...

Urban sustainable development strategies are of great importance to rapidly urbanized countries such as China. One of the most challenging problems is how to coordinate urban spatial development with social efficiency and environmental protection, e.g., highly efficient low-carbon urban traffic. Despite broad research efforts with respect to the influence of urban form on travel patterns, questions persist as to the impact of compact urban form on travel distance and modes. In this study, we adopted urban form metrics to capture key dimensions of urban form with the aid of image processing and spatial analysis based on satellite images and statistical data from the cases of 35 cities. Combined with urban travel survey data, we empirically examined the relationships between urban form and travel patterns of local urban residents. The results showed that urban form and travel patterns have regionalized characteristics, e.g., the eastern cities are characterized by disperse urban development patterns and longer commuting times on average compared with western and central cities. We found that relatively smaller built-up areas, higher degrees of urban spatial agglomeration and more paved road area per person would decrease the commuting time of urban residents. We also found that the public transport choices of urban residents are positively associated with built-up areas and commuting times, which suggests the need for provision and promotion of facilities for a high-quality public transport system. The findings provide helpful suggestions for the planning of sustainable urban form and development of transportation.

Eighteen polycyclic aromatic hydrocarbons (PAHs) in PM2.5 and PM10 are identified and quantified at five sites of E'erduosi in 2005 by GC-MS. Total PAH concentrations in PM2.5 and PM10 are in the ranges of 0.58-145.01 ng m(-3) and 5.80-180.32 ng m(-3) for the five sites, decreasing as coal-chemical base site (ZGE) g heavy industrial site (QPJ) g residential site with heavy traffic (DS) g suburban site surrounded by grassland (HJQ) g background site (QGN) for both PM2.5 and PM10. PAH concentrations in the coal-chemical base site are 250 and 31.1 times of those in the background site. Flu, Pyr, Chr, BbF, BeP, IND and BghiP are abundant for the coal-chemical base site, totally accounting for 75% of the PAH concentrations. 4, 5 and 6 rings PAHs are dominant, accounting for 88.9-94.2% and 90.5-94.1% of PAHs in PM2.5 and PM10, respectively. Combustion-derived PAH concentrations cover 42%-84% and 75%-82% of PAHs in PM2.5 and PM10, indicating large amounts of combustion sources existed for them in E'erduosi. PAH compositions between PM2.5 and PM10, are quite different from each other for sites with few human activities (HJQ and QGN) by coefficient of divergence analysis. Results obtained from principal component analysis and diagnostic ratios indicate that coal combustion, vehicle emission, wood combustion and industrial processes are the main sources for PAHs in E'erduosi. According to BaP equivalent concentration, the potential health risk of PAHs in PM2.5 at the two industrial sites ZGE and QPJ are 537 and 460 times of those for the background site. And they are 4.3 and 3.7 times of those for the residential site. The potential PAH pollution in particles at other industrial agglomeration regions that occurred in China in recent years should be paid attention by the local government (C) 2014 Elsevier B.V. All rights reserved.

The United States of America and the People’s Republic of China are responsible for over 40% of the world’s CO2 emissions annually and they will be able to effectively reduce global emissions if they fulfil their commitments jointly in climate change mitigation. Here we briefly summarize past climate collaborations between the two countries and compare their national climate policies. The major problems are the mutual distrust between the two countries and the priority of economic development over climate change mitigation within each of them. As atmospheric CO2 levels are still increasing at an accelerating rate, it is essential for the largest two emitters to turn ongoing bilateral dialogue into prompt mitigation action and maintain long-term joint efforts in reducing emissions. We suggest that the two countries should recognize and take advantage of their differences in socioeconomic, political, and technological conditions. Furthermore, the two countries need to share their experiences and technologie...

Geographical detector models provide a quantitative approach for evaluating spatial correlations among ecological factors, population density and landscape connectivity. Here, we used a geographical model to assess the influence of different gradients of urbanization, human activities and various environmental factors on the connectivity of urban forest landscapes in Xiamen, China from 1996 to 2006. Our overarching hypothesis is that human activity has modified certain ecological factors in a way that has affected the connectivity of urban forest landscapes. Therefore, spatiotemporal distributions of landscape connectivity should be similar to those of ecological factors and can be represented quantitatively. Integral indices of connectivity and population density were employed to represent urban forest landscape connectivity and human activity, respectively. We then simulated the spatial relationship between forest patches and population density with Conefor 2.6 software. A geographical detector model was used to identify the dominant factors that affect urban forest landscape connectivity. The results showed that a distance of 600 m was the threshold of node importance. Mean annual temperature, mean annual precipitation, elevation, patch area, population density and dominant species had significant effects on the node importance. Mean annual temperature was more significant than population density in controlling the spatial pattern of the delta of the integral index of connectivity (dIIC). The spatial interaction between population density and various ecological factors as well as their linearly enhanced or nonlinearity enhanced urban forest landscape connectivity. In conclusion, a combination of graph theory and geographical detector models is effective for quantitatively evaluating interactive relationships among ecological factors, population density and landscape connectivity.

As the world’s largest importer of timber, China’s challenge in forestry is to find a way to increase forest productivity and carbon sequestration. We argue that China’s state-owned forestry sector has low land productivities mainly because there are hidden barriers in the governmentally controlled forestry system. We suggest that a market-oriented forestry system should be applied to China’s commercial forests, and timber harvesting from commercial forests should not be restricted by a maximum allowable harvest quota or minimum rotation lengths imposed by the national government. The market-oriented forestry system will help increase forestland productivity and revert forest carbon sources into sinks for many degraded forest areas in China.

The global phenomenon of urbanization increases the importance of compact-city development. China’s rapid urban development has resulted in unprecedented urban population growth and built-up area expansion, but its effects on urban morphology and mobility are only partly understood. City compactness can be measured simply using urban spatial form or morphology: the more concentrated the built-up area, the more compact the city is. Here we show that 35 major cities in China are not compact in spatial form and that their compactness is not improving over time. Our results reveal close correlations between changes in urbanization rate and changes in city compactness as well as between city compactness and commuting time (CT), indicating that the high rate of urbanization without adequate planning has contributed to the poor compactness of Chinese cities, which has further increased CT. We suggest that continuing urban sprawl with low land use efficiency and low urban form compactness will make cities in Chin...

China’s state-owned forest enterprises have been important national timber production bases and their timber resources have been severely degraded during the past decades. About one-third of the state-owned forestland has been classified as commercial forestland, but no economic mechanisms have been laid out on governing timber plantations under market economy. This paper demonstrates the potential investment returns and analyzes factors that directly influence the returns of fast-growing poplar plantations in a state owned-forest enterprise, China Jilin Forest Industry Group (CJFIG), in northeastern China. We examined practically possible ranges of mean annual increment (MAI), general inflation rate, rate of forest fund, and interest rate in the study area. We then computed net present values (NPV), equivalent annual income (EAI) and internal rate of return (IRR) by using the minimum, medium, and maximum values of the each determinant above. Results showed NPV ranged from $1,024 to $6,925 ha−1, EAI ranged from $120 to $623 ha−1 year−1, and IRR ranged from 13.2 to 29.3 %. We show that growing poplar plantations could be two times more profitable than managing the existing natural forests in CJFIG by referring to EAI values. Improving MAI is the most effective way to increase both NPV and IRR while changes in the one-time tax at timber harvesting or changes in inflation rate have the least effect on NPV and IRR among the determinants studied. Discount rate, which can be easily manipulated by obtaining subsidies and policy-based loans, also has substantial influence on NPV. The state owned forest enterprises in China have special advantages to obtain relatively high economic returns in developing fast-growing plantation forests under market economy.

Monitoring the dynamics of forest biomass at various spatial scales is important for better understanding the terrestrial carbon cycle as well as improving the effectiveness of forest policies and forest management activities. In this article, field data and Landsat image data acquired in 1999 and 2007 were utilized to quantify spatiotemporal changes of forest biomass for Dongsheng Forestry Farm in Changbai Mountain region of northeastern China. We found that Landsat TM band 4 and Difference Vegetation Index with a 3 × 3 window size were the best predictors associated with forest biomass estimations in the study area. The inverse regression model with Landsat TM band 4 predictor was found to be the best model. The total forest biomass in the study area decreased slightly from 2.77 × 10(6) Mg in 1999 to 2.73 × 10(6) Mg in 2007, which agreed closely with field-based model estimates. The area of forested land increased from 17.9 × 10(3) ha in 1999 to 18.1 × 10(3) ha in 2007. The stabilization of forest biomass and the slight increase of forested land occurred in the period following implementations of national forest policies in China in 1999. The pattern of changes in both forest biomass and biomass density was altered due to different management regimes adopted in light of those policies. This study reveals the usefulness of the remote sensing-based approach for detecting and monitoring quantitative changes in forest biomass at a landscape scale.

China's rapid urbanization and its success in developing the Internet of Things (IoT) will decide its future development direction. The construction of sustainable cities is crucial to China because China has such a large population. The Xiamen Long-term Urban Ecosystem Observation and Research Station (Xiamen LUEORS) was started in 2006, together with the research related to the Environmental Internet of Things (EIoT) for Xiamen LUEORS. This paper explains the purpose, general framework, and main features of EIoT, and outlines the results of performing EIoT experiments in some areas, including a town village', a peculiar phenomenon of China's urbanization. It also discusses the development trends of IoT and proposes the concept of ZeroSpace Interconnection of Things (ZeroIoT, or ZeroSIT).

There have been a growing number of environmental problems associated with the rapid development of cities. Common environmental monitoring methods are unable to meet the dynamic needs of urban environmental management. The emergence of Internet of Things (IoT) technology provides a new way to improve urban environment monitoring and management. The Environmental Internet of Things (EIoT) makes it possible to sense, acquire, process, and transfer environmental information over a large area in real time. In this paper, we present an integrated system for urban environment monitoring and management by referring to the EIoT concept. We developed and tested the system by monitoring water, soil, air, noise, and some other environmental factors on the campus of our research institute. The system can obtain real-time environmental information in situ and express and publish its outcomes in different formats. Moreover, the system is extendible for additional sensors and environmental factors, and to cover larger ...

Villages in China have been greatly impacted by the countrywide urbanisation process, and many of them have undergone transformation in landscape structure and rapid changes in environment. However, environmental monitoring in urbanising villages, or town villages, cannot be fully realised by the existing environmental monitoring infrastructure and resources. We intended to apply Environmental Internet of Things (EIoT) technology to fulfill this task, beginning with the development of a Mobile Meteorological Monitor (3M) consisting of an ultrasonic weather station, an industrial tablet PC, a foldable mountain bicycle and a series of accessories. The initial application of 3M in environmental monitoring for a town village indicates that the monitoring capability could be expanded to carry out the monitoring of other environmental variables, such as water quality, air pollution and noise pollution. By simultaneously employing multiple 3M units, it is possible to generate a spatiotemporal framework of monito...

Forestry development in China has undergone a series of reforms over the past six decades. This article examines temporal changes in forest resources and policies, the current status of forestry, and future challenges toward sustainable forest management in China. Excessive logging in the 1950s to 1980s badly damaged the nation’s forests, but the adoption of enlightened forest policies in the late 1990s has led to increases in China’s total forest area and growing stock. Forest degradation was ecologically and economically costly, and rehabilitation processes have become increasingly more expensive. The low quality and young age of forest resources, loss of natural forests, and more difficulties in afforestation and reforestation pose severe challenges for China’s sustainable forestry. It is critically important for China to enhance forest productivity through intensive management, strengthen enforcement, and educational programs for protecting and restoring natural forests, narrow the gap between domesti...

In this article, we demonstrate an object-oriented method for detailed urban vegetation delineation by using 1 m resolution, four-band digital aerial photography as the only input data. A hierarchical classification scheme was developed to discriminate vegetation types at both coarse and fine scales. The processes of vegetation extraction include the examination of spectral and spatial relationships, object geometry, and the hierarchical relationship of image objects. The advantages of four different segmentation methods were combined to identify feature similarities, both among image objects and with their neighbours. Image growth took place if those neighbours satisfied a series of criteria given a set of features of class-defined objects. Object-based classification results demonstrated higher accuracy than those using pixel-based classification methods. The object-oriented method achieved overall classification accuracies of 87.5%, 90.5%, and 90.5% at three different levels of class hierarchy, and very high producer's accuracies were demonstrated in the classes of tree, crop, and different types of grass. The object-oriented classification method described here proved effective for separating vegetation types defined by life form, area, or shape without using additional remote-sensing data sources with different resolutions or any ancillary data such as digital elevation models.

In automatic/semiautomatic mapping of land use/cover using very high resolution remote-sensing imagery, the major challenge is that a single class of land use contains ground targets with varied spectral values, textures, geometries and spatial features. Here we present an object-oriented strategy for automatic/semiautomatic classifications of land use/cover using very high resolution remote-sensing data. The strategy consists of character detecting, object positioning and coarse classification, then refining the classification result step by step. The strategy combines the form classification of the objects located on the same level by using spectral values, textures and geometric features with function classification by using spatial logic relationships existing among the objects on the same level or between different levels. Furthermore, it overcomes the problem of transformation from form classification to function classification and unifies land use classification and land cover classification organically. Such an approach not only achieves high classification accuracy, but also avoids the salt-and-pepper effect found in conventional pixel-based procedures. The borderlines of the classification result are clear, the patches are pure, and the classification objects exactly match the ground targets distributed across the study site. A feasible technical strategy for the large-scale application is discussed in this article.

Forest fires threaten natural resources and human lives in many areas of the world. A rational assessment of forest fire risk is critical to reduce fire damage that threatens the sustainability of forest resources and their services. This is particularly true in Lijiang City, an important world heritage site. We assessed the grades of forest fire risk in Lijiang City based on the concept of a fire life cycle, using the probability of ignition in the pre-forest fire period, the capacity for detection and emergency rescue in the mid-forest fire period, and forest fire damage in the post-forest fire period. We used the analytical hierarchy process to analyse data on the ecology, economy, cultural resources, humanities and topography of Lijiang City, and geographic information systems (GIS) as a platform to integrate multi-source data. The results strongly agree with the records of reported forest fires between 2000 and 2011. This assessment method could be used in cities with large areas forestland that cont...

In the current information age, digital technology has become an essential part of urban civilisation. The digital city has been transformed from a novel concept to a practical and effective means of supporting urban planning and management. However, there are various definitions of a digital city and each has a unique significance. By comparing these digital city concepts, we examined common aspects of digital city definitions and propose an urban digital operating system (Urban DOS) that will be useful to improve life quality, socioeconomic functions and sustainable development in a city and its surrounding areas. The technical basis for the Urban DOS is the intersection between technology-oriented products (TOPs) and customised application products (CAPs). We then develop a procedure for designing a framework for a digital city based on Urban DOS with TOPs and CAPs. To explain such digital city concepts and applications, we demonstrate the initial development of Urban DOS for Lijiang City.

Changbai Mountain, the highest mountain in the east of the Eurasian Continent, is covered with a wide range of distinct altitudinal vegetation types featuring the Earth's richest biodiversity in the cool temperate zone. However, some development trends on Changbai Mountain urgently require the launching of innovative policies and actions for sustainable forest conservation on Changbai Mountain. This paper provides an overview of forest conservation issues in the area: it summarizes the ecological significance of forest vegetation on Changbai Mountain, reviews historic forest utilization and protection in the region, and discusses forest conservation measures that exist on Changbai Mountain. The paper also describes specific civilization-based economic developments, including deforestation, logging, non-wood product collection, and tourism, which threaten forest sustainability inside and around protected areas on Changbai Mountain. We propose that forest ecosystem management should be implemented outside the designated protected areas and human pressure should be reduced inside nature reserves on Changbai Mountain. Landscape and ecosystem approaches should be used to promote forest conservation at the mountain level. In addition, China and North Korea (DPRK) need to engage in multiscale, multidisciplinary, and multistakeholder transboundary conservation efforts.

Forest degradation in protected areas has been monitored around the world with remote sensing data, but degradation processes undetectable by widely used satellite sensors have been largely overlooked. Increased human pressures and socioeconomic development make forest protection more challenging, particularly for forest ecosystems that lie across national borders because of the differences in national socioeconomic policies and conditions within them. Here with Landsat data, Google Earth images, and field observations, we show that, in two adjacent biosphere reserves across the border of China and North Korea, over one half of primary forest landscapes have been deteriorated by exploitive uses, including seed harvesting and systematic logging. The combined effects of detectable and hidden degradation pro- cesses have further damaged forest ecosystems in the core areas in the two biosphere reserves, threaten- ing sustainable biodiversity conservation in the region. It is urgent to develop cross-border collaborative conservation strategies that can help combat both detectable and hidden degradation processes at a regional scale.

Urban expansion is a phenomenon of urban space increase, and an important measuring index of the process of urbanization. Taking Shanghai as an example, the changes of urban average height and built-up area were studied to represent city’s vertical and horizontal increases respectively, and statistical methods were used to analyze the driving forces of urban expansion. The research drew following conclusions: 1) The urban expansion process of Shanghai from 1985 to 2006 had a clear periodic feature, and could be divided into three stages: vertical expansion in dominance, coordinated vertical and horizontal expansion, and horizontal expansion in dominance. 2) The average height and quantity of buildings in core city were significantly bigger than those in suburbs, but the changing speed of the latter was faster. And 3) urbanization process was the major driving force for the city’s horizontal expansion, while industrial structure improvement was the key driving factor for the vertical expansion. Those two driving forces were simultaneously affected by city’s political factors.

A managed fire regime on John F. Kennedy Space Center, Florida and surrounding federal properties was mapped using time series satellite imagery and GIS techniques. Our goals were to: (1) determine if an image processing technique designed for individual fire scar mapping could be applied to an image time series for mapping a managed fire regime in a rapid re-growth pyrogenic system; (2) develop a method for labeling mapped fire scar confidence knowing a formal accuracy analysis was not possible; and (3) compare results of the managed fire regime with regional information on natural fire regimes to look for similarities/differences that might help optimize management for persistence of native fire-dependent species. We found that the area burned by managed fire peaked when the drought index was low and was reduced when the drought index was high. This contrasts with the expectations regarding the natural fire regime of this region. With altered natural fire regimes and fire-dependent species declining in many pyrogenic ecosystems, it is important to manage fire for the survival of fire-adapted native species. The remote sensing and GIS techniques presented are effective for delineating and monitoring managed fire regimes in shrub systems that grow rapidly and may be appropriate for other fire-dependent systems world wide.

China has the fifth largest forest area in the world and any change in China’s forestry development will have inevitable impacts on global ecological sustainability. China has undergone excessive logging of natural forests and also made tremendous efforts in afforestation during the past half century. China’s forestry is now going through a variety of transitions and several forestry programs have been implemented to drive forestry transitions. The goal of these actions is to protect ecological services of forests and sustain China’s forestry development. These forestry programs are spatially sophisticated and cannot be successfully implemented without accurate and transparent forest/forestry information. A variety of digital technologies, including forest modeling, remote sensing, geographic information systems, global positioning systems, and visualization, have been applied in handling diverse information in China’s forestry. Digital forestry is not just a theoretical concept in China. Our digital forestry experience in northeast China suggests that digital technology is both usable and useful in China’s forestry development. Digital technology is playing an important interactive role in China’s top-down forestry administration system. The analog-todigital transition in technology is expected to lead to the success of forestry programs and forestry transitions in China.

Reclaiming farmland from lakes in China in the 1950s damaged the water quality of many lakes. Tremendous efforts have been made since the late 1990s to restore vegetation around the damaged lakes. ...

Advances in remote sensing technologies have provided practical means for land use and land cover mapping which is critically important for landscape ecological studies. However, all classifications of remote sensing data are subject to different kinds of errors, and these errors can be carried over or propagated in subsequent landscape pattern analysis. When these uncertainties go unreported, as they do commonly in the literature, they become hidden errors. While this is apparently an important issue in the study of landscapes from either a biophysical or socioeconomic perspective, limited progress has been made in resolving this problem. Here we discuss how errors of mapped data can affect landscape metrics and possible strategies which can help improve the reliability of landscape pattern analysis.