•The scarcity value of ecosystem services (ES) was evaluated on the Qinghai-TibetanPlateau (QTP) by linking supply and demand.•The spatial heterogeneities of ES scarcity value and its response to ...urbanization were identified.•The surging demand for public-good ES contributed to a significant increase in scarcity value.•There was a spatial consistency between ES scarcity value and economic conditions during urbanization.
As a result of the land degradation it causes, rapid urbanization can severely impact the form and function of the natural environment. Because of the limited availability of natural capital and the ecosystem services they provide in many regions, fluctuations in supply and demand should rigorously considered in decision-making. The Qinghai-Tibetan Plateau (QTP) is a globally-important ecoregion that generates significant ecosystem services value. Focusing on the QTP, we calculated the value change in the supply of ecosystem services using a coefficient table and the change in demand based on population, GDP, and income elasticity. The impact of supply and demand on the scarcity value of ecosystem services (ESSV) was then compared across four representative scenarios. The results showed that the ESSV on the QTP rose considerably between 1990 and 2020, particularly between 2000 and 2010. Between 1990 and 2020, the public-goods services grew faster than private-goods services. The most important element impacting the ESSV was demand-driven scarcity. The level of urbanization gradually increased during 1990–2020, with a consistent distribution of high ESSV and high urbanization across the region. High-High types and Low-Low types had a significant aggregation effect, located primarily in the north and west of the QTP, respectively. The Low-High type was scattered along with the Low-Low type, indicating fragile ecological conditions that merit greater protection from land degradation. The degree of coupling reveals an increasing degree of synergy between ESSV and urbanization on the QTP, indicating potential for more synergistic development.
Context
The Sanjiangyuan region of the Qinghai-Tibetan Plateau—also known as the “Three Rivers’ Headwaters”—is the origin of the Yellow, Yangtze, and Mekong Rivers and therefore the key water source ...for hundreds of millions of downstream residents. Protecting this region’s ecosystems is a key priority for sustainable development in China and Asia. An important social dimension of Sanjiangyuan is the long-established and widespread presence of Tibetan Buddhism, particularly as manifested in the large number of monasteries throughout the region. However, the influence of cultural factors on environmental change remains largely understudied here.
Objective
We focus on two types of spatial associations—point-point and point-area features—to quantitatively investigate the effects of Buddhist monasteries on land use/cover change (LUCC) in surrounding landscapes.
Methods
We conduct a spatially-explicit analysis of Sanjiangyuan for two periods, 1990–2000 and 2010–2015, to identify and quantify the influence of the presence and spatial distributions of Buddhist monasteries on LUCC compared to village communities that lack monasteries.
Results
We found that the presence of monasteries is highly correlated with the preservation of natural ecosystems, specifically of grasslands and forests. Within monastery buffer zones with radii between 1 and 10 km, 7.13–9.30% more grassland area and 7.14–7.47% more forest area remained around monasteries compared to villages. This contrast decreased with increasing distance to the monastery/village. Overall, built-up areas were also much smaller around monasteries than around villages, while unused land was more commonly transformed to forests and grasslands around monasteries.
Conclusions
These findings strongly support the idea that Buddhist culture, as manifested through its physical institutions and communities, are instrumental in achieving desired landscape conservation outcomes.
The Yushu Tibetan Autonomous Prefecture is a typical Tibetan plateau area, and its ecological environment is very fragile. It is necessary to explore the terrain and cultural factors for the ...protection of the local ecological environment. We mainly investigated and quantified the effect of terrain factors and two typical plateau cultural landscapes (temples and villages) on the spatiotemporal variation characteristics of four types of forest landscape in the Yushu Tibetan Autonomous Prefecture from 1990 to 2015 using remote sensing (RS) and geographic information system (GIS) technology. The results showed that, under the influence of terrain factors, forest landscapes were only distributed in places with an altitude of 5055 meters above sea level (masl) to 6300 masl, with a slope of 0–27°, and the largest distribution area was shrubbery. The area of the forest decreased with the increase in altitude, and it first rose and then decreased with the increase in slope. Regression analysis results showed that the influence of altitude on closed forest land and open forest land followed a polynomial function, while that on shrubbery followed a logarithmic function, and the impact of slope on the three forest landscapes followed the amplitude version of a Gaussian peak function. Considering cultural factors, temples and villages did not determine the forest distribution in the same way as natural factors do, but they motivated the amount of forest over spatiotemporal scales. Temples had a greater influence on forest protection than villages, and this positive impact was stronger within 6 km. The area of forest distributed around the temple accounts for more than 45.67% of the total forest area, and this area has not changed significantly in 25 years. In summary, altitude and slope affect the natural distribution of the forest, and temples affect the scale of forest distribution. These results reveal the impact of terrain factors and cultural landscapes on forest distribution and could motivate an even more effective management for sustainable forest development.
Synthetic hexaploid wheat （Triticum turgidum x Aegilops tauschii） was created to explore for novel genes from T. turgidum and Ae. tauschii that can be used for common wheat improvement. In the ...present paper, research advances on the utilization of synthetic hexaploid wheat for wheat genetic improvement in China are reviewed. Over 200 synthetic hexaploid wheat （SHW） accessions from the International Maize and Wheat Improvement Centre （CIMMYT） were introduced into China since 1995. Four cultivars derived from these, Chuanmai 38, Chuanmai 42, Chuanmai 43 and Chuanmai 47, have been released in China. Of these, Chuanmai 42, with large kernels and resistance to stripe rust, had the highest average yield （〉 6 t/ha） among all cultivars over two years in Sichuan provincial yield trials, outyielding the commercial check cultivar Chuanmai 107 by 22,7%. Meanwhile, by either artificial chromosome doubling via colchicine treatment or spontaneous chromosome doubling via a union of unreduced gametes （2n） from T. turgidum-Ae, tauschii hybrids, new SHW lines were produced in China. Mitotic-like meiosis might be the cytological mechanism of spontaneous chromosome doubling. SHW lines with genes for spontaneous chromosome doubling may be useful for producing new SHW-alien amphidiploids and double haploid in wheat genetic improvement.
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•eDNA metabarcoding conquers limitations of traditional methods in fish diversity.•78 fish taxa were identified by eDNA metabarcoding and bottom trawling.•eDNA metabarcoding detected ...significantly more fish species per site and per season.•eDNA metabarcoding reflected the seasonal fluctuation of fish diversity as well.•eDNA metabarcoding could be applied to studying fish diversity in coastal wetland.
The difficulty of censusing fish diversity hampers effective management and conservation in estuarine and coastal ecosystems, especially wetland ecosystems. Improved noninvasive fish diversity monitoring programs are becoming increasingly crucial for coastal ecosystems. In this study, we investigated fish diversity and its seasonal variation in the Nansha wetland ecosystem using environmental DNA (eDNA) metabarcoding and bottom trawling, and the two approaches were compared. With the combination of the two methods, the identified fish taxa included 78 species within 60 genera and 33 families, and five nontarget taxa were only identified by eDNA metabarcoding. Compared to the two surveys, eDNA metabarcoding identified a significantly greater number of fish species per site and per season than bottom trawling (p < 0.05), with eDNA metabarcoding identifying 32.05% more fish species than bottom trawling. The overwhelming majority of the fish orders captured in the Nansha coastal wetland by bottom trawling were recovered from eDNA analysis, although certain taxa were not sampled due to limitations. Furthermore, the Whittaker index and relative abundance analysis of the two methods showed distinct differences between the sampling seasons, suggesting seasonal variations and reflecting the current or recent existence of fish species in the coastal ecosystem. Thus, our work provides more detailed seasonal data on biodiversity in the Nansha wetland of the Pearl River Estuary, which is essential for the long-term management and conservation of coastal biodiversity. Our study also adds to the evidence that the eDNA metabarcoding approach can be used in coastal environments to monitor a broad range of taxa and reflect seasonal fluctuations in fish diversity. As an emerging and transformative method, eDNA metabarcoding shows great potential for fish diversity monitoring in coastal wetland ecosystems.
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•Progress of non-oxide semiconductors for photoelectrochemical solar fuel production is summarized.•Protection strategies to increase the operational durability of non-oxide ...photoelectrodes are highlighted.•The effects of interfacial energy diagrams on charge transfer kinetics at various interfaces are presented.•Future perspectives for development of efficient and stable non-oxide solar-fuel photoelectrodes are discussed.
Among various artificial photosynthesis routes, photoelectrochemical (PEC) hydrogen (H2) production via water splitting and hydrocarbon generation via carbon dioxide (CO2) reduction are particularly intriguing for achieving a sustainable society. A simpler and potentially economical device design for PEC cells, as compared with those containing photovoltaic cells, is using semiconductor–liquid junction (SCLJ) based photoelectrodes to assemble a photoanode–photocathode tandem cell. The SCLJs form immediately upon semiconductor films immersing into electrolytes, which are then used to separate photogenerated electron–hole pairs and drive corresponding redox chemistry. To engineering these SCLJ-based photoanode–photocathode tandem PEC devices to achieving considerable solar energy conversion efficiencies, the key step is to identify suitable semiconductor materials, the core component in most solar energy conversion systems. In addition, applying effective strategies to modify these semiconductors are needed, as they cannot simultaneously meet all the requirements of efficient light absorption, charge separation and extraction, surface reaction, and operational stability at the same time. This article provides a review on promising non-oxide semiconductors for PEC conversion of solar energy into chemical fuels. The efforts to increase charge transport and separation, to accelerate the charge transfer kinetics across various interfaces, and to engender long-term durability of these non-oxide photoelectrodes are emphasized. As screening, evaluation and optimization have led to substantial improvement in both PEC performance and operational durability, non-oxide semiconductors will provide new opportunities, in addition to classical metal oxide semiconductors, to realize efficient and cost-effective PEC solar fuel production.
Petrological observations and in situ major and trace element and Sr isotopic data for spinel-facies harzburgite and lherzolite xenoliths from the Siziwangqi region provide constraints on the nature ...and evolution of the lithospheric mantle beneath the northwestern North China Craton (NCC). These peridotites can be divided into high-Mg# peridotites (Fo > 91) and low-Mg# peridotites (Fo < 91), according to olivine forsterite (Fo) contents. The high-Mg# peridotites are harzburgites, which are characterized by high Mg# (91.0–91.8), as well as low CaO (0.41–1.17 wt%) and Al2O3 (0.62–2.03 wt%) contents. The clinopyroxenes have light rare earth element (LREE) depleted to slightly enriched patterns, and variable but dominantly radiogenic Sr isotopic compositions (0.7031–0.7053). These features indicate that the high-Mg# peridotites are remnants of Archean–Paleoproterozoic refractory lithospheric mantle, which then experienced variable refertilization. In contrast, the low-Mg# peridotites are mainly lherzolites and minor harzburgites, which have low Mg# (89.2–90.9), and high CaO (0.98–3.53 wt%) and Al2O3 (1.38–3.85 wt%) contents, relative to the high-Mg# peridotites. The clinopyroxenes in low-Mg# peridotites have similar REE patterns as those in the high-Mg# peridotites, and some grains show increasing LREE contents from core to rim. These clinopyroxenes have relatively depleted Sr isotopic compositions (0.7021–0.7045). The low-Mg# peridotites are interpreted to be the reaction products of high-Mg# peridotites and asthenospheric melts. The lithospheric mantle beneath the Siziwangqi region experienced an earlier metasomatic event related to subduction of Paleo-Asian oceanic materials, as evidenced by the relatively high 87Sr/86Sr ratios (up to 0.7053) and depletion of Rb, Ba, Pb, Nb and Ta in clinopyroxenes. The clinopyroxenes in both high- and low-Mg# peridotites have low (La/Yb)N and high Ti/Eu ratios, positive correlations between 87Sr/86Sr and Mg# and Ca/Al, negative correlations between 87Sr/86Sr and Na2O, TiO2, Ti/Eu, and Σ(middle REEs + heavy REEs), and decreasing 87Sr/86Sr ratios from core to rim. These observations imply that the lithospheric mantle beneath the Siziwangqi region experienced later multi-stage refertilization by asthenospheric melts. Therefore, we conclude that the lithospheric mantle beneath the northwestern NCC has been comprehensively refertilized by multiple stages of peridotite–melt reactions, similar to the northern margin of the NCC, which had a significant role in the transformation of the lithospheric mantle.
•SCLM beneath the northwestern NCC is studied by in situ Sr isotopes of peridotites.•There exists the remnants of Archean–Paleoproterozoic lithospheric mantle.•SCLM was modified by multiple stages of mantle metasomatism.•Refertilization leads to the transformation of Archean–Paleoproterozoic mantle.
The sustainable production of chemicals and fuels from abundant solar energy and renewable carbon sources provides a promising route to reduce climate-changing CO
emissions and our dependence on ...fossil resources. Here, we demonstrate solar-powered formate production from readily available biomass wastes and CO
feedstocks via photoelectrochemistry. Non-precious NiOOH/α-Fe
O
and Bi/GaN/Si wafer were used as photoanode and photocathode, respectively. Concurrent photoanodic biomass oxidation and photocathodic CO
reduction towards formate with high Faradaic efficiencies over 85% were achieved at both photoelectrodes. The integrated biomass-CO
photoelectrolysis system reduces the cell voltage by 32% due to the thermodynamically favorable biomass oxidation over conventional water oxidation. Moreover, we show solar-driven formate production with a record-high yield of 23.3 μmol cm
h
as well as high robustness using the hybrid photoelectrode system. The present work opens opportunities for sustainable chemical and fuel production using abundant and renewable resources on earth-sunlight, biomass and CO
.
The Mesozoic was a critical period for the evolution of the North China Craton (NCC). We present the petrological observations and in situ mineral major and trace elements and Sr isotopic data for ...spinel harzburgite and lherzolite xenoliths in Late Cretaceous Fuxin basalts from the northern margin of the NCC. These data are used to investigate the nature and evolution of the subcontinental lithospheric mantle (SCLM) beneath the NCC during the Mesozoic. The peridotite xenoliths commonly have porphyroclastic and granoblastic textures, and can be divided into high-Mg# and low-Mg# peridotites. Compared with the low-Mg# peridotites, the high-Mg# peridotites have higher olivine Fo (>91) and spinel Cr# values (>35), and their clinopyroxenes are light REE-enriched with uniform 87Sr/86Sr ratios (ca. 0.7042). These observations suggest that the high-Mg# peridotites could be relics of old SCLM and were metasomatized by melts derived from subducted Paleo-Asian oceanic slab. The low-Mg# peridotites are characterized by minerals with sieve textures and melt pockets. The olivine Fo of the low-Mg# peridotites are low and variable (81.2–90.4), and decrease from core to rim in some crystals. Thus, the low-Mg# peridotites underwent extensive peridotite–melt interactions. Their clinopyroxenes are enriched in LREE and show large variations in the 87Sr/86Sr ratios (0.7039–0.7052). Moreover, 87Sr/86Sr ratios positively correlate with MgO and negatively correlate with Al2O3, Eu and Dy contents. These observations suggest that the low-Mg# peridotites experienced multiple stages of mantle metasomatism, involving high-87Sr/86Sr melts derived from the subducted Paleo-Asian oceanic crust in early stage and low-87Sr/86Sr melts derived from more recent asthenospheric upwelling. Therefore, the low-Mg# peridotites are representative of SCLM fragments that were strongly modified beneath the Fuxin region during the Late Cretaceous. Combined with previous studies, our findings suggest that refertilization of the SCLM by asthenospheric melts beneath the northern margin of the NCC commenced before eruption of the Fuxin basalts (ca. 100 Ma), which is much earlier than previously thought. This process resulted in a highly heterogeneous SCLM. In addition, the Tan–Lu Fault contributed substantially to the evolution of the SCLM beneath the NCC during the Mesozoic.
•Mesozoic SCLM beneath NCC is studied by in situ Sr isotopes of peridotite xenoliths•Refertilization of SCLM by asthenospheric melts commenced before 100 Ma•Multiple metasomatisms resulted in the Mesozoic heterogeneous SCLM•Tan-Lu Fault played an important role in the Mesozoic SCLM evolution beneath NCC
This study investigated the relative role of sub-syllabic components (initial consonant, rime, and tone) in spoken word recognition of Mandarin Chinese using an eye-tracking experiment with a visual ...world paradigm. Native Mandarin speakers (all born and grew up in Beijing) were presented with four pictures and an auditory stimulus. They were required to click the picture according to the sound stimulus they heard, and their eye movements were tracked during this process. For a target word (e.g.,
"candy"), nine conditions of competitors were constructed in terms of the amount of their phonological overlap with the target: consonant competitor (e.g.,
"ladder"), rime competitor (e.g.,
"wave"), tone competitor (e.g.,
"cow"), consonant plus rime competitor (e.g.,
"soup"), consonant plus tone competitor (e.g.,
"head"), rime plus tone competitor (e.g.,
"sheep"), cohort competitor (e.g.,
"tower"), cohort plus tone competitor (e.g.,
"peach"), and baseline competitor (e.g.,
"snow"). A growth curve analysis was conducted with the fixation to competitors, targets, and distractors, and the results showed that (1) competitors with consonant or rime overlap can be adequately activated, while tone overlap plays a weaker role since additional tonal information can strengthen the competitive effect only when it was added to a candidate that already bears much phonological similarity with the target. (2) Mandarin words are processed in an incremental way in the time course of word recognition since different partially overlapping competitors could be activated immediately; (3) like the pattern found in English, both cohort and rime competitors were activated to compete for lexical activation, but these two competitors were not temporally distinctive and mainly differed in the size of their competitive effects. Generally, the gradation of activation based on the phonological similarity between target and candidates found in this study was in line with the continuous mapping models and may reflect a strategy of native speakers shaped by the informative characteristics of the interaction among different sub-syllabic components.
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