Urban expansion dynamics and natural habitat loss in China: a multiscale landscape perspective

China's extensive urbanization has resulted in a massive loss of natural habitat, which is threatening the nation's biodiversity and socioeconomic sustainability. A timely and accurate understanding of natural habitat loss caused by urban expansion will allow more informed and effective measures to be taken for the conservation of biodiversity. However, the impact of urban expansion on natural habitats is not well‐understood, primarily due to the lack of accurate spatial information regarding urban expansion across China. In this study, we proposed an approach that can be used to accurately summarize the dynamics of urban expansion in China over two recent decades (1992–2012), by integrating data on nighttime light levels, a vegetation index, and land surface temperature. The natural habitat loss during the time period was evaluated at the national, ecoregional, and local scales. The results revealed that China had experienced extremely rapid urban growth from 1992 to 2012 with an average annual growth rate of 8.74%, in contrast with the global average of 3.20%. The massive urban expansion has resulted in significant natural habitat loss in some areas in China. Special attention needs to be paid to the Pearl River Delta, where 25.79% or 1518 km² of the natural habitat and 41.99% or 760 km² of the local wetlands were lost during 1992–2012. This raises serious concerns about species viability and biodiversity. Effective policies and regulations must be implemented and enforced to sustain regional and national development in the context of rapid urbanization.     

时空变化视角下北京市湿地优先保护格局

气候变化通过改变湿地水文过程等影响湿地的空间分布,城市化进程加剧了湿地破碎化程度并导致湿地生境退化,构建连续的湿地生态保护网络体系有利于应对气候变化和城市发展带来的负面影响、提高生物多样性保护水平。北京市现有湿地空间分布呈现斑块面积小、破碎化程度高等特点,为优化湿地保护区格局并应对气候变化和城市发展对北京市湿地生物多样性的影响,基于系统保护规划方法,以Marxan作为空间优化模型,结合PLUS模型和MaxEnt模型,模拟预测北京市湿地优先保护格局、识别湿地保护空缺并构建湿地分级保护区格局。研究表明:2020年北京市湿地存在80.15km²的保护空缺、2035年和2050年优化后湿地保护区占比分别为87.54%和85.95%,在满足本研究预设的生物多样性保护目标的前提下符合北京市湿地保护规划对湿地保护率的要求。为最优化资源分配,综合时空变化对湿地保护区空间分布的影响,构建了湿地分级保护区格局,将湿地保护区分为湿地永久保护区、湿地一级临时保护区和湿地二级临时保护区三个等级,以期为北京市分期建设湿地保护区、优化湿地生态保护网络体系和保护湿地生物多样性提供依据。     

Future land use effects on the connectivity of protected area networks in southeastern Spain

Land-use change is a major driver of the global biodiversity crisis, mainly via the fragmentation and loss of natural habitat. Although land-use changes will accelerate to meet humankind's growing demand for agricultural products, conservation planning rarely considers future land uses and how they may affect the connectivity of ecological networks. Here, we integrate land-use models with landscape fragmentation and connectivity analyses, to assess the effects of past and future land-use changes on the connectivity of protected area networks for a highly dynamic region in southeast Spain. Our results show a continued geographical polarisation of land use, with agricultural intensification and urban development in the coastal areas, and the abandonment of traditional land use in the mountains (e.g., 1100 km² of natural vegetation are projected to be lost in coastal areas whereas 32 km² of natural vegetation would recover in interior areas from 1991 to 2015). As a result, coastal protected areas will experience increasing isolation. The connectivity analyses reveal that the two protected area networks in place in the study area, the European “Natura 2000” and the Andalusian “RENPA” networks, include many landscape connectors. However, we identify two areas that currently lack protection but contain several important patches for maintaining the region's habitat connectivity: the northwestern and the southwestern slopes of the Sierra Cabrera and Bédar protected area. Our results highlight the importance of considering future land-use trajectories in conservation planning to maintain connectivity at the regional scale, and to improve the resilience of conservation networks.     

Assessing the effectiveness of protected areas for conserving range-restricted rain forest butterflies in Sabah,Borneo

Rain forests on Borneo support exceptional concentrations of endemic insect biodiversity, but many of these forest-dependent species are threatened by land-use change. Totally protected areas (TPAs) of forest are key for conserving biodiversity, and we examined the effectiveness of the current TPA network for conserving range-restricted butterflies in Sabah (Malaysian Borneo). We found that mean diurnal temperature range and precipitation of the wettest quarter of the year were the most important predictors of butterfly distributions (N = 77 range-restricted species), and that species richness increased with elevation and aboveground forest carbon. On average across all species, TPAs were effective at conserving ~43% of species’ ranges, but encompassed only ~40% of areas with high species richness (i.e., containing at least 50% of our study species). The TPA network also included only 33%–40% of areas identified as high priority for conserving range-restricted species, as determined by a systematic conservation prioritization analysis. Hence, the current TPA network is reasonably effective at conserving range-restricted butterflies, although considerable areas of high species richness (6,565 km²) and high conservation priority (11,152–12,531 km²) are not currently protected. Sabah's remaining forests, and the range-restricted species they support, are under continued threat from agricultural expansion and urban development, and our study highlights important areas of rain forest that require enhanced protection.     

Predictive mapping of two endemic oak tree species under climate change scenarios in a semiarid region: Range overlap and implications for conservation

Quercus infectoria and Quercus libani are two important species distributed across most of the Kurdistan Region of Iraq's mountain ranges (KRI). They have significant ecological, medicinal, and socioeconomic values. Recent studies have documented how plant distributions have been impacted by climate change. This study's goal is to establish the existing distributions of both species, measure the consequences of prospective environmental conditions on their distributions, predict possible habitat distributions, map the overlapped habitat ranges for the species in the KRI, and identify the key factors influencing their distributions. For these aims, distribution data points of the species, different environmental factors, including the existing climate, three emission predictions for the 2050s, 2070s, and 2090s of two general circulation models (GCMs), a machine learning approach, and geospatial techniques were used. Modeling revealed that the total magnitude of the habitat increase for the species would be less than the overall magnitude of the habitat contraction. The yearly mean temperature, yearly precipitation, and minimum temperature during the coldest period mostly alter the target species' geographic dispersion. Across the three emission scenarios of the both models, Q. infectoria habitat would contract by 2760.9–2856.9 km² (5.36–5.55%), 2856.9–3357.2 km² (5.55–6.52%) and 2822.1–3400.2 km² (5.48–6.60%), whereas it would expand by 1153.3–1638.9 km² (2.24–3.18%), 761.0–1556.8 km² (1.48–3.02%), and 721.5–1547.1 km² (1.40–3.00%) for the 2050s, 2070s, and 2090s, respectively. A similar pattern was also noted for Q. libani. The two species' habitat ranges in KRI would be considerably reduced due to climate change. The species' estimated area would extend mostly to the east and southeast of the KRI at high altitudes. The mountain areas, notably those where the species overlap by 1767.2–1807.5 km² (3.43–3.51%) for the two GCMs, must be the primary objective of conservation efforts. This research presents new baseline data for future research on mountain forest ecosystems and the techniques of biodiversity conservation to reduce climate change's effects in Iraq.     

Protected areas of Borneo fail to protect forest landscapes with high habitat connectivity

Throughout the world, previously extensive areas of natural habitats have been degraded and fragmented, and improving habitat connectivity may help the long-term persistence of species, and their ability to adapt to climate changes. We focused on Borneo, where many remaining areas of tropical forest are highly fragmented, and we assessed the extent to which Protected Areas (PAs) protect highly-connected forest sites. We analysed remotely-sensed land cover data (0.86 km² grid cell resolution) using ‘Zonation’ reserve design software, and we ranked grid cells (rank 0–1) according to forest extent and connectivity. PAs currently cover 9% of Borneo, but <20% of highly-connected cells (i.e. cells with Zonation ranks ≥0.9) lie within PAs. Approximately 65% of highly-connected cells were located above 400 m elevation, although >60% of Borneo’s total land area lies below 200 m and only 15% of highly-connected cells occurred in these low elevation areas. These findings were relatively insensitive to assumptions about species’ dispersal ability (within the range 1–20 km; representing relatively mobile animal species). The percentage of highly-connected grid cells within PAs could rise from <20 to >50% under proposed new PAs (including the ‘Heart of Borneo’ project), although many other highly-connected sites will remain unprotected. On-going land-use changes mean that existing PAs in lowland areas are likely to become increasingly isolated within inhospitable agricultural landscapes, and improving connectivity through reforestation and rehabilitation of degraded forest may be required to maintain the conservation value of these PAs in future.     

Determination of priority nature conservation areas and human disturbances in the Yangtze River Basin,China

Because of limitation of manpower, funding, and land available in conservation, the problem of how to select essential regions to establish protection systems for biodiversity maintenance has been widely discussed. In an effort to address the problem, this study has aimed to select a set of priority areas and to determine their priority order by quantifying human disturbances for each area in the Yangtze River Basin (YRB). This basin covers 2.143 million km², or more than 20% of China's territory. The habitats of 627 indicator species were predicted as a proxy for biodiversity. A conservation planning tool, MARXAN, was used to determine the optimal set of planning units, and three different target scenarios were generated. In addition, under the assumption that if two areas have equal value for conservation, the one suffering more severe disturbance needs more urgent protection than the other, priority ranking analysis was carried out using a 6-12-1 BP artificial neural network. Then hierarchical cluster analysis was applied to the classifications of human disturbances to formulate more detailed conservation strategies. By integrating the degree of irreplaceability of each unit, expert experience, and mountain boundaries, 17 biodiversity priority areas containing 33,200 units over an area of 0.83 million km² were defined. These areas also protected 56% of 32 types of rare forest ecosystem and 76.4% of six types of rare grassland ecosystem on average. According to the evaluation of human impact, a priority order and five types of human disturbance areas were generated. Some protection gaps were also identified, such as the northern part of the Wuyi Mountains. Moreover, the determination of priority nature conservation areas on a large scale can be used to influence the building of a well-connected protection network in each individual area, so that effective genetic communication can occur between species or groups of species. Conservation decisions focusing on the dominant impact factors that are threatening biodiversity sustainability are required as well.     

Organic Carbon Storage in China's Urban Areas

China has been experiencing rapid urbanization in parallel with its economic boom over the past three decades. To date, the organic carbon storage in China''s urban areas has not been quantified. Here, using data compiled from literature review and statistical yearbooks, we estimated that total carbon storage in China''s urban areas was 577±60 Tg C (1 Tg  = 10¹² g) in 2006. Soil was the largest contributor to total carbon storage (56%), followed by buildings (36%), and vegetation (7%), while carbon storage in humans was relatively small (1%). The carbon density in China''s urban areas was 17.1±1.8 kg C m⁻², about two times the national average of all lands. The most sensitive variable in estimating urban carbon storage was urban area. Examining urban carbon storages over a wide range of spatial extents in China and in the United States, we found a strong linear relationship between total urban carbon storage and total urban area, with a specific urban carbon storage of 16 Tg C for every 1,000 km² urban area. This value might be useful for estimating urban carbon storage at regional to global scales. Our results also showed that the fraction of carbon storage in urban green spaces was still much lower in China relative to western countries, suggesting a great potential to mitigate climate change through urban greening and green spaces management in China.     

Seasonal habitat use by Elephants (Loxodonta africana) in the Mole National Park of Ghana

To avoid unnecessary waste of limited resources and to help prioritize areas for conservation efforts, this study aimed to provide information on habitat use by elephants between the wet and dry seasons in the Mole National Park (MNP) of Ghana. We compiled coordinates of 516 locations of elephants’ encounters, 256 for dry season and 260 for wet season. Using nine predictor variables, we modeled the probability of elephant's distribution in MNP. We threshold the models to “suitable” and “nonsuitable” regions of habitat use using the equal training sensitivity and specificity values of 0.177 and 0.181 for the dry and wet seasons, respectively. Accuracy assessment of our models revealed a sensitivity score of 0.909 and 0.974, and a specificity of 0.579 and 0.753 for the dry and wet seasons, respectively. A TSS of 0.488 was also recorded for the dry season and 0.727 for the wet season indicating a good model agreement. Our model predicts habitat use to be confined to the southern portion of MNP due to elevation difference and a relatively steep slope that separates the northern regions of the park from the south. Regions of habitat use for the wet season were 856 km² and reduced significantly to 547.68 km² in the dry season. We observed significant overlap (327.24 km²) in habitat use regions between the wet and dry seasons (Schoener's D = 0.922 and Hellinger's‐based I = 0.991). DEM, proximity to waterholes, and saltlicks were identified as the key variables that contributed to the prediction. We recommend construction of temporal camps in regions of habitat use that are far from the headquarters area for effective management of elephants. Also, an increase in water point's density around the headquarters areas and selected dry areas of the park will further decrease elephant's range and hence a relatively less resource use in monitoring and patrols.     

Urban expansion and its consumption of high-quality farmland in Beijing,China

China faces the challenge of using limited farmland to feed more than 1.3 billion people. Accelerated urbanization has exacerbated this challenge by consuming a large quantity of high-quality farmland (HQF). It is therefore essential to assess the degree to which urban expansion has preferentially consumed HQF, and discern the mechanism behind this. We found urban areas in Beijing to expand at speeds of 48.97 km²/year, 21.89 km²/year, 62.30 km²/year and 20.32 km²/year during the periods 1986–1995, 1995–2000, 2000–2005 and 2005–2020, respectively. We developed an indicator of HQF consumption due to urban expansion, representing the ratio of HQF consumed to its proportion of overall farmland, and found its values were 2.21, 1.57, 1.99 and 1.10 for 1986–1995, 1995–2000, 2000–2005 and 2005–2020, respectively. Thus, although HQF has been overrepresented in the farmland consumed by Beijing's urbanization, this phenomenon has decreased over time. Centralized expansion has contributed greatly to consumption of HQF. Topography and distances to urban and water bodies determine the relative consumption of HQF in urbanization.     

Identifying the habitat suitability and built-in corridors for Asiatic black bear (Ursus thibetanus) movement in the northern highlands of Pakistan

Identifying habitat suitability and potential corridors are important tools for biodiversity conservation in the face of climate change. We modeled habitat suitability and simulated possible corridors for movement and gene flow among the Asiatic black bear (Ursus thibetanus) population in the Northern Highlands of Pakistan (NHP). Results indicated that the areas of 13,923 km² and 21,931 km² suitable for the Asiatic black bear under current and future scenarios respectively. Under the future scenario, we found an area of 12,657 km² (57.21%) as increase in suitable habitat (ISH_f) and 4649 km² (33.39%) area as a decrease in current suitable habitat (DSH_c). Our model predicted that about >65% (9274 km²) of the current suitable habitat as a climate refugia which is projected from the center to southeast east and northwest of the NHP primarily in the Khyber Pakhtunkhwa (KPK) and Pakistan Administered Kashmir (PAK). The attitudinal range of refugia was projected from 688 m to 4483 m with >56% at the elevations between 2001 m to 3000 m. A very small portion of suitable habitats (current suitable habitat = 2.75%, future suitable habitat = 5.11%) were projected under the protected areas. Maps connecting suitable habitats identified different regions delineated as important for the dispersal of Asiatic black bears, which mainly distributed in the PAK and KPK. Our results help informs conservation strategies and management plans for mitigating the impacts of climate change on Asiatic black bears in the NHP.     

基于水体型生态指数的无锡市城区生态质量时空变化分析

水体是构成生态质量的重要指标,传统的城市生态质量评价方法通常掩膜了水体区域,忽略了水对生态质量的影响。基于Google Earth Engine(GEE)平台提供的2013、2015、2017、2019、2021年的Landsat8-OLI影像数据,利用信息熵权重法耦合水体丰度(SPWI)、比率植被指数(RVI)、归一化潜热指数(NDLI)、干度(NDSI)、热度(LST)构建水体型生态指数(WBEI),对江苏省无锡市城区2013—2021年生态质量进行时空变化分析,并利用Moran指数计算无锡市城区生态质量的空间自相关性。结果表明：(1)WBEI融合了水体对生态指数的影响,弥补了传统方法无法反映水体区域生态质量的不足,能更好地反映包含水体区域在内的城市生态质量;(2)2013—2021年,无锡市城区平均WBEI分别为0.4808、0.4416、0.5068、0.4471、0.4682,城区生态质量呈波动变化,总体呈小幅下降的趋势;(3)无锡市城区生态质量极好等级的面积减少67.5251km²,良好与一般等级增加76.8633km²,生态质量...     

Spatio-temporal habitat assessment of the Gangetic floodplain in the Hastinapur wildlife sanctuary

Remote sensing provides multi-dimensional and multi-temporal information about habitat, insights into the significant drivers of change, and the key factors affecting landscape dynamics. Such information is crucial to provide perspective and a more profound understanding of ecological surveys. This study utilizes Google Earth Engine's capability to assess a riverine wetland grassland floodplain in Hastinapur Wildlife Sanctuary (HWS) along the Ganga River, which is a critical habitat for wintering migratory birds, the critically endangered gharial, turtles, aquatic mammals such as otters and dolphins, and cervid species such as swamp deer. We have developed a framework for regular monitoring through rapid habitat assessment, which visualizes the spatio-temporal change in land cover, the seasonal dynamics in water and vegetation, changes due to anthropogenic influences on the landscape, and finally, how these factors affect the habitat availability of species of concern in the HWS. The results show a dynamic river system with high seasonal variations. The vegetation trend shows increasing greenness, indicative of the conversion of grassland, scrubland, and herbaceous cover to more permanent vegetation, which will adversely affect the riparian habitat structure. A habitat suitability index generated through geospatial analysis using the weighted overlay method suggests that 40.07% of the HWS, nearly 767.12 km², comprising mainly the riverscape, wetland, and riparian grasslands, is suitable habitat for aquatic and semi-aquatic species. However, only 9.93% of the sanctuary comprising 197.27 km², is available as a core habitat. Further, the area is threatened by encroachment evident from the rapidly increasing land-use intensity and night light pollution, which puts the grasslands sheltered to swamp deer and other wildlife at higher risk leaving almost 27.9% of the area comprising 533.63 km² unsuitable for wildlife. Urban and agricultural land use has taken over 67% of the sanctuary. An increase in minimum radiance value representing ALAN, from 0.41 to 0.73 W/m²-sr in just six years from 2015 to 2021, shows a reduction in nocturnal darkness, reducing safe niches for wildlife. The study results provide critical baseline information for ecological surveys and a rapid assessment platform for future sanctuary management. Constant monitoring of anthropogenic activities such as farming, settlements, and transport routes threatening the habitat is essential for informed conservation management decisions.     

The Lion in West Africa Is Critically Endangered

The African lion has declined to <35,000 individuals occupying 25% of its historic range. The situation is most critical for the geographically isolated populations in West Africa, where the species is considered regionally endangered. Elevating their conservation significance, recent molecular studies establish the genetic distinctiveness of West and Central African lions from other extant African populations. Interventions to save West African lions are urgently required. However formulating effective conservation strategies has been hampered by a lack of data on the species'' current distribution, status, and potential management deficiencies of protected areas (PAs) harboring lions. Our study synthesized available expert opinion and field data to close this knowledge gap, and formulate recommendations for the conservation of West African lions. We undertook lion surveys in 13 large (>500 km²) PAs and compiled evidence of lion presence/absence for a further eight PAs. All PAs were situated within Lion Conservation Units, geographical units designated as priority lion areas by wildlife experts at a regional lion conservation workshop in 2005. Lions were confirmed in only 4 PAs, and our results suggest that only 406 (273–605) lions remain in West Africa, representing <250 mature individuals. Confirmed lion range is estimated at 49,000 km², or 1.1% of historical range in West Africa. PAs retaining lions were larger than PAs without lions and had significantly higher management budgets. We encourage revision of lion taxonomy, to recognize the genetic distinctiveness of West African lions and highlight their potentially unique conservation value. Further, we call for listing of the lion as critically endangered in West Africa, under criterion C2a(ii) for populations with <250 mature individuals. Finally, considering the relative poverty of lion range states in West Africa, we call for urgent mobilization of investment from the international community to assist range states to increase management effectiveness of PAs retaining lions.     

Rapid expansion of the invasive-like red macroalga,Chondria tumulosa (Rhodophyta), on the coral reefs of the Papahānaumokuākea Marine National Monument

A cryptogenic, invasive-like red macroalga, Chondria tumulosa, was first observed in 2016 forming thick mats on the forereef of Manawai Atoll within Papahānaumokuākea Marine National Monument. Subsequent expeditions revealed an increased abundance of this alga. In 2021, unattached C. tumulosa was observed forming a network of dark, meandering accumulations throughout the atoll's inner lagoon. High-resolution satellite imagery revealed that these accumulations became visible in 2015 (length: ~0.74 km; area: ~0.88 km²) and increased 56-fold in length and 115-fold in area by 2021 (length: 41.32 km; area: 101.34 km²). An exponential expansion rate of ~16.02 km · y⁻¹ (length), ~44.75 km² · y⁻¹ (area). This study presents the comprehensive temporal and spatial expansion of C. tumulosa accumulations for Manawai Atoll since its discovery, providing ecologist and resource managers with a proxy to gauge the overall abundance trend of this invasive-like alga.     

Regional Assessment of Urban Impacts on Landcover and Open Space Finds a Smart Urban Growth Policy Performs Little Better than Business as Usual

Assessment of landscape change is critical for attainment of regional sustainability goals. Urban growth assessments are needed because over half the global population now lives in cities, which impact biodiversity, ecosystem structure and ecological processes. Open space protection is needed to preserve these attributes, and provide the resources humans need. The San Francisco Bay Area, California, is challenged to accommodate a population increase of 3.07 million while maintaining the region’s ecosystems and biodiversity. Our analysis of 9275 km² in the Bay Area links historic trends for three measures: urban growth, protected open space, and landcover types over the last 70 years to future 2050 projections of urban growth and open space. Protected open space totaled 348 km² (3.7% of the area) in 1940, and expanded to 2221 km² (20.2%) currently. An additional 1038 km² of protected open space is targeted (35.1%). Urban area historically increased from 396.5 km² to 2239 km² (24.1% of the area). Urban growth during this time mostly occurred at the expense of agricultural landscapes (62.9%) rather than natural vegetation. Smart Growth development has been advanced as a preferred alternative in many planning circles, but we found that it conserved only marginally more open space than Business-as-usual when using an urban growth model to portray policies for future urban growth. Scenarios to 2050 suggest urban development on non-urban lands of 1091, 956, or 179 km², under Business-as-usual, Smart Growth and Infill policy growth scenarios, respectively. The Smart Growth policy converts 88% of natural lands and agriculture used by Business-as-usual, while Infill used only 40% of those lands. Given the historic rate of urban growth, 0.25%/year, and limited space available, the Infill scenario is recommended. While the data may differ, the use of an historic and future framework to track these three variables can be easily applied to other metropolitan areas.     

Long-term desertification process monitoring and driving factors analysis in rare earth mining area

With the exploitation of rare earth elements (REE) in southern China, desertification has become a serious ecological problem in this region. To accurately understand the desertification process in mining areas and formulate targeted ecological restoration programs, taking the Lingbei mining area in Ganzhou City, Jiangxi Province as the study area, we explored desertification information extraction methods, desertification dynamics monitoring, and desertification drivers in REE mining areas using multisource data from 1986 to 2021. The results show that from the method of extracting desertification information, Random Forest is the prominent (83.33%), followed by Albedo–NDVI (Normalized Difference Vegetation Index) space (74.44%), and thirdly Linear Spectral Mixture Model (65.56%). From 1986 to 2021, the desertification land area in Lingbei mining areas first increased and then decreased, showing a reverse trend, but it has not recovered to the pre-mining level. The government's ecological reclamation measures are the key factors for the restoration of desertification land. There are still 17.81 km² areas that have not been restored, of which 2.16 km² are at the level of severe desertification. Moderate desertification and light desertification have not been completely curbed, which needs continuous attention. Vegetation coverage has the highest explanatory power to the distribution of land desertification in mining areas, followed by land use classification, indicating that human activities have a great influence on the spatial differentiation of land desertification in mining areas, and it is necessary to pay attention to regional balanced and sustainable development in the future.     

Renewable energy development threatens many globally important biodiversity areas

Transitioning from fossil fuels to renewable energy is fundamental for halting anthropogenic climate change. However, renewable energy facilities can be land‐use intensive and impact conservation areas, and little attention has been given to whether the aggregated effect of energy transitions poses a substantial threat to global biodiversity. Here, we assess the extent of current and likely future renewable energy infrastructure associated with onshore wind, hydropower and solar photovoltaic generation, within three important conservation areas: protected areas (PAs), Key Biodiversity Areas (KBAs) and Earth's remaining wilderness. We identified 2,206 fully operational renewable energy facilities within the boundaries of these conservation areas, with another 922 facilities under development. Combined, these facilities span and are degrading 886 PAs, 749 KBAs and 40 distinct wilderness areas. Two trends are particularly concerning. First, while the majority of historical overlap occurs in Western Europe, the renewable electricity facilities under development increasingly overlap with conservation areas in Southeast Asia, a globally important region for biodiversity. Second, this next wave of renewable energy infrastructure represents a ~30% increase in the number of PAs and KBAs impacted and could increase the number of compromised wilderness areas by ~60%. If the world continues to rapidly transition towards renewable energy these areas will face increasing pressure to allow infrastructure expansion. Coordinated planning of renewable energy expansion and biodiversity conservation is essential to avoid conflicts that compromise their respective objectives.     

辽宁中部城市群城市增长时空格局及其驱动力

基于1988、1992、1997、2000和2004年5期Landsat TM卫星遥感影像数据,采用GIS空间分析和景观格局分析的方法,分析了辽宁中部城市群城市增长的时空格局特征,并对其驱动力进行了探讨.结果表明: 1988-2004年间,辽宁中部城市群城市面积持续增加,增长强度逐渐增强, 城市面积由812.55 km²增至1345.86km², 平均增长速率为32-96 km²·a^-1;1997年以后,城市增长强度迅速增大,以1997-2000年的城市扩展强度最大;辽宁中部城市群的城市增长主要集中在中部城镇密集带.1988-1997年,研究区城市面积的增长速度较慢,空间结构紧凑,以边缘增长和填充增长为主;1997-2004年,城市面积增长较快,表现为扩散的城市增长格局和复杂的城市斑块形状,以开发区的飞地式增长和扩散增长为主.非农业人口增长、经济增长、城市群城市空间的相互吸引、工业发展与开发区建设政策等因素是辽宁中部城市群城市空间快速增长的主要驱动力.     

Land suitability for energy crops under scenarios of climate change and land‐use

Bioenergy is expected to play a critical role in climate change mitigation. Most integrated assessment models assume an expansion of agricultural land for cultivation of energy crops. This study examines the suitability of land for growing a range of energy crops on areas that are not required for food production, accounting for climate change impacts and conservation requirements. A global fuzzy logic model is employed to ascertain the suitable cropping areas for a number of sugar, starch and oil crops, energy grasses and short rotation tree species that could be grown specifically for energy. Two climate change scenarios are modelled (RCP2.6 and RCP8.5), along with two scenarios representing the land which cannot be used for energy crops due to forest and biodiversity conservation, food agriculture and urban areas. Results indicate that 40% of the global area currently suitable for energy crops overlaps with food land and 31% overlaps with forested or protected areas, highlighting hotspots of potential land competition risks. Approximately 18.8 million km² is suitable for energy crops, to some degree, and does not overlap with protected, forested, urban or food agricultural land. Under the climate change scenario RCP8.5, this increases to 19.6 million km² by the end of the century. Broadly, climate change is projected to decrease suitable areas in southern regions and increase them in northern regions, most notably for grass crops in Russia and China, indicating that potential production areas will shift northwards which could potentially affect domestic use and trade of biomass significantly. The majority of the land which becomes suitable is in current grasslands and is just marginally or moderately suitable. This study therefore highlights the vital importance of further studies examining the carbon and ecosystem balance of this potential land‐use change, energy crop yields in sub‐optimal soil and climatic conditions and potential impacts on livelihoods.