4,144 research outputs found
Identifying hotspots and management of critical ecosystem services in rapidly urbanizing Yangtze River Delta Region, China
Rapid urbanization has altered many ecosystems, causing a decline in many ecosystem services, generating serious ecological crisis. To cope with these challenges, we presented a comprehensive framework comprising five core steps for identifying and managing hotspots of critical ecosystem services in a rapid urbanizing region. This framework was applied in the case study of the Yangtze River Delta (YRD) Region. The study showed that there was large spatial heterogeneity in the hotspots of ecosystem services in the region, hotspots of supporting services and regulating services aggregately distributing in the southwest mountainous areas while hotspots of provisioning services mainly in the northeast plain, and hotspots of cultural services widespread in the waterbodies and southwest mountainous areas. The regionalization of the critical ecosystem services was made through the hotspot analysis. This study provided valuable information for environmental planning and management in a rapid urbanizing region and helped improve China's ecological redlines policy at regional scale
Recommended from our members
China's building stock estimation and energy intensity analysis
Reliable and objective data regarding building stock is essential for predicting and analyzing energy demand and carbon emission. However, China's building stock data is lacking. This study proposes a set of China building floor space estimation method (CBFSM) based on the improved building stock turnover model. Then it measures China's building stocks by vintage and type from 2000 to 2015, as well as building energy intensity (national level and provincial level) and energy-efficient buildings. Results showed that total building stocks increased significantly, rising from 35.2 billion m2 in 2000 to 63.6 billion m2 in 2015, with the average growth rate 4.0%. The deviations were well below 10% by comparing with China Population Census, which validated the reliability of CBFSM and the results. As for energy intensity, urban dwellings and rural dwellings showed relatively stable and increasing trend respectively. The commercial building energy intensity saw a downward trend during “12th Five Year Plan” period. This indicated the effectiveness of building energy efficiency work for commercial buildings since 2005.38.6 billion m2 residential dwellings and 5.7 billion m2 commercial buildings still need to be retrofitted in future. CBFSM can overcome shortages in previous studies. It can also provide Chinese government with technical support and data evidence to promote the building energy efficiency work
Effects of the merger history on the merger rate density of primordial black hole binaries
We develop a formalism to calculate the merger rate density of primordial
black hole binaries with a general mass function, by taking into account the
merger history of primordial black holes. We apply the formalism to three
specific mass functions, monochromatic, power-law and log-normal cases. In the
former case, the merger rate density is dominated by the single-merger events,
while in the latter two cases, the contribution of the multiple-merger events
on the merger rate density can not be ignored. The effects of the merger
history on the merger rate density depend on the mass function.Comment: 9 pages, 7 figures; V2, references added, discussion added, title
changed. v3, a new subsection adde
STUDY OF APPLICATION OF THZ TIME DOMAIN SPECTROSCOPY IN FOOD SAFETY
Abstract: In this paper, a new spectroscopy technology named terahertz time-domain spectroscopy (THz-TDS) is introduced, which is used in food safety. We describe a coherent subpicosecond THz spectroscopy system based on nonresonant optical rectification for the generation of THz radiation. As an example, we measured absorption spectrum of water vapor by THz-TDS in frequency from 0.5 to 2.5 THz, The experiment demonstrated that the spectroscopy resolution of system was up to 0.0001THz, which can be measured vegetable pesticide residual, for it neither need sample pretreatment nor cause pollution
Topological superconductor to Anderson localization transition in one-dimensional incommensurate lattices
We study the competition of disorder and superconductivity for a
one-dimensional p-wave superconductor in incommensurate potentials. With the
increase in the strength of the incommensurate potential, the system undergoes
a transition from a topological superconducting phase to a topologically
trivial localized phase. The phase boundary is determined both numerically and
analytically from various aspects and the topological superconducting phase is
characterized by the presence of Majorana edge fermions in the system with open
boundary conditions. We also calculate the topological invariant of the
bulk system and find it can be used to distinguish the different topological
phases even for a disordered system.Comment: 5 + 4 pages, 5 +2 figures, version appeared in PRL, supplementary
material include
Gravitational and electromagnetic radiation from binary black holes with electric and magnetic charges: Elliptical orbits on a cone
Extending the electromagnetic and gravitational radiations from binary black
holes with electric and magnetic charges in circular orbits in Phys. Rev. D
{\bf 102}, 103520 (2020), we calculate the total emission rates of energy and
angular momentum due to gravitational and electromagnetic radiations from
dyonic binary black holes in precessing elliptical orbits. It is shown that the
emission rates of energy and angular momentum due to gravitational and
electromagnetic radiations have the same dependence on the conic angle for
different orbits. Moreover, we obtain the evolutions of orbits and find that a
circular orbit remains circular while an elliptic orbit becomes quasi-circular
due to electromagnetic and gravitational radiations. Using the evolution of
orbits, we derive the waveform models for dyonic binary black hole inspirals
and show the amplitudes of the gravitational waves for dyonic binary black hole
inspirals differ from those for Schwarzschild binary black hole inspirals,
which can be used to test electric and magnetic charges of black holes.Comment: 10 pages, 2 figures, a new section adde
- …