Northwestern Plateau Research Articles

Rainfall characteristics under changing climate in Sundergarh district of Odisha

Most pronounced signal of warming world is the increase in intensity and frequency of extremeevents worldwide. Many researchers have reported the nature of these events in coastal district of Odisha, but forSundergarh district which comes under North-western Plateau Agro-Climatic Zone, it still needed to be studied. Thepresent study was conducted with an objective to study rainfall characteristics - rainfall climatology, rainy days, trend -their deviation and resulting meteorological drought in Sundergarh district of Odisha at block level using 34 years ofdaily rainfall data (1988-2022). IMD classification for rainy days was adopted to determine the frequency of rainy days indifferent categories. SPI was computed using Climpact to determine the occurrence and severity of meteorologicaldrought and identify episodes of dry and wet events during the study period for each block. MK test and Sen’s slopeestimator was used for detecting trend in rainfall (annual and seasonal) and rainy days at 95% significance level. Longterm rainfall analysis reveals that the mean annual rainfall of the district is 1290 ± 314 mm, most of which is receivedduring SW monsoon (86%) followed by post-monsoon (6.2%), pre-monsoon (5.7%) and least during winter (2.1%).Rainfall received in the months of July and August together accounts for more than 50% of the total. Spatial distributionof rainfall indicated that mean annual rainfall varies from 1071 mm (Subdega) to 1578 mm (Bonai). Annually, rainfall isdependable in most of the blocks. However, during pre-monsoon, post-monsoon and winter, CV is very high, so therainfall is not dependable. Bulk of annual rainfall received in the district is contributed by rain events of light to moderatecategory. Direction and magnitude of the trend of rainfall amount and rainy days varies a lot in different blocks. SPI values calculated for the district as a whole shows that frequency of occurrence of these drought events were: mild (34% of months); moderate (7.6% of months); severe (3.3% of months) and extreme (3.2% of months). The present study provides pertinent information on the rainfall climatology and its trend under climate change over the Sundergarh district of Odisha. Finding of the study suggests that there is an urgent need to raise awareness about the climate resilient society, train personnels about sustainable development approaches and highlight the necessity of water harvesting techniques at community level.

Groundwater recharge sources and mechanisms in the Ethiopian central Afar rift: Insights from isotopic and hydrogeochemical tracers.

Groundwater flow and recharge mechanisms in the central Afar rift and the associated western marginal grabens and Northwestern Plateau (NWP) are poorly understood because of the complex geology and spatial heterogeneity in the aquifer systems. The major aquifers in the region include the Oligocene and Pliocene to recent volcanics and recent alluvio-lacustrine sediments. We employed hydrogeochemical, stable isotopes of water (18O and 2H), and geological structures insights to identify groundwater recharge sources and mechanisms, aiming to develop a representative conceptual groundwater flow model. Water samples from groundwater and surface water were collected based on lithological/aquifer variation and geomorphological setup for isotope and hydrochemical analysis. Findings reveal distinct isotopic differences between the deep (>350 m) and shallow groundwater systems of the Afar rift, with deep systems showing relative isotopic depletion, indicating varying recharge sources. The deep groundwater exhibited a similar isotopic signature to that of the marginal grabens and NWP. The distribution of major ion chemistry and electric conductivity (EC) of groundwaters from the western plateau to the Afar rift show significant spatial variability. However, in some corridors of western parts of the rift, there is a clear geochemical evolution along the flow paths inferring groundwater flow continuity between aquifers. The results revealed the existence of preferential deep groundwater recharge from the NWP through the highly fractured linking zones, interacting fault zones in between the marginal grabens, to the deeper volcanic aquifers of the central Afar rift. The proposed groundwater flow model of this study illustrates the deep groundwater flow from the NWP to the Afar rift is primarily directed by the orientations of the faulted marginal grabens and the highly fractured interacting zones. This model is pivotal for understanding groundwater dynamics in similar continental rift environments, offering insights for effective groundwater management.

Analysis of Meteorological Element Variation Characteristics in the Heilongjiang (Amur) River Basin

Located in the Heilongjiang (Amur) River in north-east Asia, spanning four countries, plays a crucial role as an international border river, and its meteorological changes significantly impact the variation in water resources in the basin. This study utilizes daily average temperature and precipitation data from 282 meteorological stations in the Heilongjiang (Amur) River Basin and its surrounding areas for the period 1980–2022. The analysis employs spatial interpolation, change point testing, and model construction prediction methods. The results indicate a significant increasing trend in both overall temperature and precipitation changes within the Heilongjiang (Amur) River Basin. At the spatial scale, the annual warming rate increases gradually from the southeastern coastal region to the northwestern plateau region, while the rate of precipitation increase decreases from the southern area towards its surroundings. Temporally, the warming amplitude during the growing season decreases gradually from east to west, and the trend in precipitation changes during the growing season aligns with the overall annual precipitation trend. During the non-growing season, the warming trend shows a decrease in the plains and an increase in the plateau, while precipitation increase concentrates in the central and southern plains, and precipitation decrease predominantly occurs in the northwestern plateau region. Temperature and precipitation change points occurred in the years 2001 and 2012, respectively. In precipitation prediction, the Long Short-Term Memory (LSTM) model exhibits higher accuracy, with R (Pearson correlation coefficient) and NSE (Nash-Sutcliffe efficiency coefficient) values approaching 1 and lower NRSME values. This study provides a research foundation for the rational development and utilization of water resources in the Heilongjiang (Amur) River Basin and offers valuable insights for research on climate change characteristics in large transboundary river systems.

Validation of MODIS Temperature and Emissivity Products Based on Ground-Based Mid-Wave Hyperspectral Imaging Measurement in the Northwestern Plateau Region of Qinghai, China

The climatic fluctuations in northern China exhibit remarkable variability, making it imperative to harness the power of MODIS data for conducting comprehensive investigations into the influences of desertification, desert expansion, and snow and ice melting phenomena. Consequently, the rigorous evaluation of MODIS land surface temperature (LST) and land surface emissivity (LSE) products takes on a momentous role, as this provides an essential means to ensure data accuracy, thereby instilling confidence in the robustness of scientific analyses. In this study, a high-resolution hyperspectral imaging instrument was utilized to measure mid-wave hyperspectral images of grasslands and deserts in the northwest plateau region of Qinghai, China. The measured data were processed in order to remove the effects of sensor noise, atmospheric radiation, transmission attenuation, and scattering caused by sunlight and atmospheric radiation. Inversion of the temperature field and spectral emissivity was performed on the measured data. The inverted data were compared and validated against MODIS land surface temperature and emissivity products. The validation results showed that the absolute errors of emissivity of grassland backgrounds provided by MCD11C1 in the three mid-wave infrared bands (3.66–3.840 μm, 3.929–3.989 μm, and 4.010–4.080 μm) were 0.0376, 0.0191, and 0.0429, with relative errors of 3.9%, 2.1%, and 4.8%, respectively. For desert backgrounds, the absolute errors of emissivity were 0.0057, 0.0458, and 0.0412, with relative errors of 0.4%, 4.9%, and 3.9%, respectively. The relative errors for each channel were all within 5%. Regarding the temperature data products, compared to the inverted temperatures of the deserts and grasslands, the remote sensing temperatures provided by MOD11L2 had absolute errors of ±2.3 K and ±4.1 K, with relative errors of 1.4% and 0.7%, respectively. The relative errors for the temperature products were all within 2%.

Effect of tillage and land levelling practices on productivity of transplanted rice: A case study in canal command area of north western plateau agro-climatic zone

An on-farm study on the response of transplanted rice to land preparation methods was undertaken on a sandy clay loam soil in Pitamahal irrigation command of Sundargarh district (Odisha) for two consecutive dry seasons of 2019-20 and 2020-21. The treatments included normal ploughing with desi plough followed by levelling of 0.5 – 1 % slope (T1), deep ploughing (20 - 25 cm) with bullock drawn M.B. plough followed by levelling of 0 - 0.25 % slope (T2), and farmers' practice of ploughing with desi plough and levelling varying 1-3 % slope (T3) for puddling operation. Deep ploughing (T2) resulted in higher root length (23.88 cm) and root 3 volume (81.75 cm ), owing to the initial rapid growth of roots promoted by deep ploughing that cracked the hardpan. This also increased the movement of water both laterally and vertically (7.44 mm per day) compared to T1 and T3's 5.11 and 5.71 m per day, respectively. The treatment also resulted in a significantly greater grain yield -1 (45.90 q ha ) due to a much larger effective tiller m-2 (423.40) and number of grains per panicle (71.80), as well as a higher net return per rupee spent (7.54) and benefitcost ratio (2.01).

Long term spatiotemporal trends and health risk assessment of remotely sensed PM2.5 concentrations in Nigeria

PM2.5 is an important indicator reflecting air quality variations. Currently, environmental pollution related issues have become more severe that significantly threaten human health. The current study is an attempt to analyze the spatio-dynamic characteristics of PM2.5 in Nigeria based on the directional distribution and trend clustering analysis from 2001 to 2019. The results indicated that PM2.5 concentration increased in most of the Nigerian states, particularly in mid-northern and southern states. The lowest PM2.5 concentration in Nigeria is even beyond the interim target-1 (35 μg/m3) of the WHO. During the study period, the average PM2.5 concentration increased at a growth rate of 0.2 μg/m3/yr from 69 μg/m3 to 81 μg/m3. The growth rate varied from region to region. Kano, Jigawa, Katsina, Bauchi, Yobe, and Zamfara experienced the fastest growth rate of 0.9 μg/m3/yr with 77.9 μg/m3 mean concentration. The median center of the national average PM2.5 moved toward the north indicating the highest PM2.5 concentration in northern states. The Saharan desert dust is the dominant source of PM2.5 in northern areas. Moreover, agricultural practices and deforestation activities along with low rainfall increase desertification and air pollution in these regions. Health risks increased in most of the mid-northern and southern states. The extent of ultra-high health risk (UHR) areas corresponding to the 8×104−7.3×106 μg⋅person/m3 increased from 1.5% to 2.8%. Mainly Kano, Lagos, Oyo, Edo, Osun, Ekiti, southeastern Kwara, Kogi, Enugu, Anambra, Northeastern Imo, Abia, River, Delta, northeastern Bayelsa, Akwa Ibom, Ebonyi, Abuja, Northern Kaduna, Katsina, Jigawa, central Sokoto, northeastern Zamfara, central Borno, central Adamawa, and northwestern Plateau are under UHR areas.

Endangered Curcuma caesia Roxb.: Qualitative and quantitative analysis for identification of industrially important elite genotypes

Black turmeric (Curcuma caesia Roxb.) of Zingiberaceae family is an industrially important critically endangered herb, found to have a captivating influence in the realm of traditional medicine. Now that this species is enlisted under critically endangered category and the repercussion of its unavailability in the terrestrial flora exempts us from scientifically exploring its potential biochemical constituents in terms of pharmaceutical and other industrial uses. So, in the present study, the industrially important qualitative and quantitative traits of black turmeric (n = 50) from different climatic zones were studied to select elite genotypes with respect to high anthocyanin and essential oil content. The genotype of Koraput was found to yield high anthocyanin content (7.14%) and high leaf oil content (1.25%) while genotype of Deoghati yields high rhizome oil content (2.55%). The quality analysis of essential oil by Gas Chromatography-Mass Spectroscopy showed the presence of eucalyptol and camphor as major compounds in leaf and rhizome oils respectively. The selected elite genotypes mostly belong to North Western Plateau, North Eastern Ghat, Eastern Ghat High Land, and South Eastern Ghat agroclimatic zones. Further, 5 elite genotypes from 4 different agroclimatic zones were recommended as industrially important high yielding traits (Anthocyanin > 6%, leaf oil ≥ 1.2%, rhizome oil >1.5%, eucalyptol >20%, and camphor >21%.) and found to be most favourable for the cultivation.

Pollen-based biome reconstruction on the Qinghai-Tibetan Plateau during the past 15,000 years

Reconstruction of past vegetation change is critical for better understanding the potential impact of future global change on the fragile alpine ecosystems of the Qinghai-Tibetan Plateau (QTP). In this paper, pollen assemblages comprising 58 records from the QTP, spanning the past 15 kyrs, were collected to reconstruct biome compositions using a standard approach. Six forest biomes were identified mainly on the southeastern plateau, exhibiting a pattern of gradual expansion along the eastern margin during early to mid-Holocene times. The alpine meadow biome was separately identified based on an updated scheme, and showed notable westward expansions towards lower latitudes and higher altitudes during early Holocene times. Consistent patterns of migration could also be identified for the alpine steppe biome, which moved eastward during the late Holocene after 4 ka. As the dominant biome type, temperate steppe was distributed widely over the QTP with minor migration patterns, except for a progressive expansion to lower altitudes in the late Holocene times. The desert biome was inferred mainly as covering the northwestern plateau and the Qaidam Basin, in relatively restricted areas. The spatial distribution of the reconstructed biomes represent the large-scale vegetation gradient on the QTP. Monsoonal precipitation expressed predominant controls on the development of alpine ecosystems, while the variations in desert vegetation responded to regional moisture brought by the mid-latitude Westerlies. Temperature changes played relatively minor roles in the variations of alpine vegetation, but exerted more significant impacts on the forest biomes.

The mitochondrial genome and phylogenetic analysis of the tick Haemaphysalis qinghaiensis Teng, 1980 (Acari:Ixodidae)

Haemaphysalis qinghaiensis is an endemic species and mainly inhabiting in the northwestern plateau of China, which can transmit many zoonotic pathogens and cause great harm to animals. In this study, the complete mitochondrial genome (mitogenome) of H. qinghaiensis was assembled through the Illumina HiSeq platform. The mitogenome was 14,533 bp in length, consisting of 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes and 3 noncoding regions (NCRs). The bias towards a high A+T content with 77.65% in mitogenome of H. qinghaiensis. The rearrangement of mitochondrial genes in H. qinghaiensis was consistent with other hard ticks. The phylogenetic analysis based on the concatenation of 13 PCGs from 65 tick mitogenomes showed that the H. qinghaiensis was clustered into a well-supported clade within the Haemaphysalis genus. This is the first complete mitogenome sequence of H. qinghaiensis, which provides a useful reference for understanding of the taxonomic and genetics of ticks.

Mineral and Climatic Controls Over Soil Organic Matter Stability Across the Tibetan Alpine Permafrost Region

AbstractPermafrost thaw could accelerate microbial decomposition, lead to greenhouse gases emissions into the atmosphere, and thus trigger a positive feedback to climate warming. As a key parameter reflecting the resistance of soil organic matter (SOM) to be decomposed by microorganisms, SOM stability may determine the strength of permafrost carbon (C)‐climate feedback. Adequate understanding of patterns and drivers of SOM stability can thus contribute to predicting permafrost C cycle and its feedback to climate change. However, due to limited observations, it remains unknown whether biochemical selectivity or physico‐chemical protection dominates SOM stability in permafrost regions. By combining large‐scale soil sampling, thermal analysis and random forest model, we quantified SOM stability in the top 10 cm using thermogravimetry and differential scanning calorimetry, and explored its spatial patterns across the Tibetan alpine permafrost region. We then constructed structural equation model to evaluate the relative importance of climatic variables, edaphic properties, substrate quality, and mineral variables in regulating SOM stability over a broad geographic scale. Our results indicated that SOM stability exhibited an increasing tendency from the southeastern to northwestern plateau. The stronger SOM stability was associated with higher mineral‐organic associations and more arid conditions. By contrast, substrate quality had limited effects on SOM stability. Overall, these results provide large‐scale evidence for the physico‐chemical protection hypothesis, highlighting the importance of considering mineral variables in Earth system models to better predict soil C dynamics across permafrost regions.

Estimating ground-level PM2.5 concentrations using two-stage model in Beijing-Tianjin-Hebei, China

In this study, a two-stage model (linear mixed-effect [LME] model + geographically weighted regression model) that could account for the spatiotemporal variability of the relationship of particulate matter less than 2.5 μm in diameter (PM2.5) and aerosol optical depth (AOD) was developed to estimate ground-level PM2.5 concentrations based on satellite-retrieved AOD products. The Beijing–Tianjin–Hebei (BTH) region was set as an example. In situ PM2.5 measurements from 80 monitoring stations and AODs from the Moderate Resolution Imaging Spectroradiometer in 2016 were used to evaluate and validate the model performance. The spatiotemporal coverage of AOD products was expanded, and the bandwidth parameters of the model were appropriately selected. Results reveal that the two-stage model effectively improves PM2.5 estimation precision. The overall coefficient of determination (R2) of the model after being cross-validated against ground observations is 0.890. The root mean squared prediction error, the mean absolute prediction error, and the relative prediction error are 19.752 μg/m3, 11.343 μg/m3, and 28.477%, respectively. The performance of the two-stage model is much better than that of the LME model. Our estimates indicate that the overall gridded annual mean PM2.5 estimation is 59.240 μg/m3 (range of 24.531–94.581 μg/m3). High values are mainly found in southern plains, while low values are observed in northwestern plateau mountain areas. The most heavily polluted season is winter, followed by fall and spring, whereas the least polluted season is summer. Therefore, the proposed two-stage model may serve as a reference for monitoring the BTH region with heavy PM2.5 pollution.

Thermo-Rheological Properties of the Ethiopian Lithosphere and Evidence for Transient Fluid Induced Lower Crustal Seismicity Beneath the Ethiopian Rift

Lower crustal earthquakes at plate boundaries and intraplate settings occur at depth where deformation is normally expected to occur in a ductile manner. Here we use the available earthquake catalogs and compute theoretical predictions for a range of conditions for the occurrence of lower crustal earthquakes beneath the Main Ethiopian Rift (MER) and adjacent north-western (NW) plateau. Yield strength envelops are constructed using information on geothermal gradient, strain rate, and composition constrained by geophysical observations. Our models suggest that away from the MER beneath the NW plateau the depth distribution of earthquakes in the lower crust is best explained by strong mafic lower crustal rheology and hydrostatic fluid pore pressure conditions. In the same region the effective elastic thickness is similar to seismogenic thickness showing that the lower crust has long-term strength and hence can physically support brittle deformation. On the contrary, in the central MER the seismogenic thickness is much larger than the effective elastic layer thickness implying that the lower crust has no long-term strength. Here our models show that both hydrostatic and near-lithostatic fluid pore pressures fail to explain the observed seismicity and instead a combination of near-lithostatic pore fluid pressure and transient high strain rate due to the movement of fluids provide a plausible mechanism for the occurrence of seismicity in the lower crust. Our interpretations are supported by occurrence of swarms of deep earthquakes beneath the MER, as opposed to more continuous background deep seismicity away from the rift. Using time-depth progression of earthquakes, we estimate permeability values of 5.9 × 10−15m2and 1.8 × 10−14m2at lower crustal depth. The range of permeability implies that seismicity can be induced by pore-pressure diffusion, likely from fluids sourced from the mantle that reactivate preexisting faults in the lower crust. Our thermo-rheological models explain the first order differences in lower crustal earthquakes both directly beneath and outboard of the rift valley.

基于景观安全格局的嘉绒藏族传统村落形态研究——以马尔康市直波村为例

PDF HTML阅读 XML下载 导出引用 引用提醒 基于景观安全格局的嘉绒藏族传统村落形态研究——以马尔康市直波村为例 DOI: 10.5846/stxb202002190291 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（51908475） Research on traditional village form of Jiarong Tibetan based on landscape security pattern: a case study of Zhibo village in Barkam City Author: Affiliation: Fund Project: The National Natural Science Foundation of China (General Program, Key Program, Major Research Plan) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以优化土地利用、实现村落形态可持续发展为导向，以景观安全格局的理论为基础对高原传统村落形态进行定量化研究。运用最小累积阻力模型和信息量评价模型相结合的方法，选取坡度、坡向、高程差、距水体距离、距道路距离、土地资源和文化景观7个阻力评价因子，构建研究区景观格局体系并分析其村落形态与土地利用的适宜关系。以直波村为例，将之分为4种等级的景观安全水平，共104个"源"地，其由低到高的景观格局及"源"地分为乡土建筑遗产保护源、民俗风情影响源、自然景观影响源、开放空间影响源，占研究区面积的比例分别为29.44%、25.35%、32.41%、12.8%；通过各阻力评价因子的最小累计阻力值和信息量值的大小影响村落形态"源"地的分布概率，计算出研究区村落形态"源"地未来适宜用地范围在高程为2501-2522 m、坡度为9°-15°、坡向为南坡、西坡、西北坡；结合景观安全水平提出土地利用可考虑两种情景：一是根据村落形态重新赋予新的功能，二是采用渐进式更新。研究结果表明通过探究土地利用与村落形态的关系，既能够较好解决人地空间关系，推进川西北高原乡村振兴建设，同时实现嘉绒藏族传统村落形态的存续。 Abstract:In order to achieve sustainable development of village form and optimization use of land resource, the traditional village form on plateau was researched quantitatively based on the theory of landscape security pattern. Accompanied with analysis of suitable relationship between the village form and the land use, the landscape pattern architecture of study region was constructed by the method of combined model, composed of the minimum cumulative resistance and the information amount evaluation, in which seven resistance evaluation factors were applied, namely slope, aspect, elevation difference, distance to water body, distance to road, land resources and cultural landscape. In the case study of Zhibo village, a traditional village of Jiarong Tibetan in Barkam, the village was divided into four landscape security levels from low to high level and 104 sources of village form. All sources of village form in Zhibo were classified into four categories: local architectural heritage protection source, folk customs influence source, natural landscape influence source, and open space influence source, whose distribution proportion in study region were 29.44%, 25.35%, 32.41%, and 12.8%, respectively. The suitable direction of future development of the village form sources was illustrated as follows according to the distribution probability of the village form sources effected by the quantitative values of the minimum cumulative resistance and the information. The elevation should be between 2501 and 2522 m. The slope should be between 9° and 15°. The aspect should be south slope, west slope and northwest slope. Considering the landscape security level, two situations of land use are suggested. The first one is that the new function will be granted to land use based on the village form. The other one is the land use will be gradually updated. The results indicate that the study on relationship between the land use and the village form can provide not only an effective solution that can solve the problems between human being and the land space, but also a significant promotion that can improve the rural construction in the northwestern plateau of Sichuan and preserve the traditional village form of the Jiarong Tibetan. 参考文献 相似文献 引证文献

Two fossil thrips from Ethiopian amber (Thysanoptera) with description of Merothrips aithiopicus sp. n. (Thysanoptera: Merothripidae).

Amber has rarely been found in Africa and only a few samples with fossil inclusions are known (Kiefert et al. 2015). The most important fossiliferous find was reported from an outcrop at the north-western Plateau of Ethiopia a decade ago, revealing diverse inclusions of arthropods, plant remains, fungi and microorganisms (Schmidt et al. 2010). Initially, this amber was classified as originating from the mid-Cretaceous. Later studies, however, have raised questions about this determination and indicated a much younger age: Cenozoic, likely Miocene (Coty et al. 2016, Perrichot et al. 2016, Perrichot et al. 2018). The contradictory-and rather controversial discussed-new dating was based on spectroscopic analyses, revised palynological data and more comprehensive palaeoentomological results showing that insect fossils mostly belong to extant families and genera. In total, Schmidt et al. (2010) reported 22 insects from eight identified orders including two specimens of Thysanoptera: "an undetermined, wingless thrips" (obviously a larva) and a female associated with Merothripidae. A more detailed analysis of these specimens is the objective of the present study; regarding the larva, only a rough classification and description is given, as fossil larvae cannot be definitely associated with adult specimens.

Assessment of ecosystem services of rice farms in eastern India

BackgroundRice is a major cereal crop and staple food of eastern India, and most farmers depend solely on rice for their livelihood. Rice farming provides both tangible and non-tangible benefits to ecosystems which need to be maintained and enhanced. These benefits are provided through ecosystem services (ES) that include both marketable and non-marketable.MethodsIn this study, the rice farms in eastern India were valued by quantifying the economic value of the services under conventional method of rice cultivation and the gap of ecosystem services value and farm income per unit area were assessed. A stratified random sampling technique was used in this study for selection of agro-climatic zones, districts, blocks, gram panchayat, and study units (households). Soil sampling was also performed for assessing the regulating services (biocontrol of pests, carbon flow, soil erosion, nitrogen fixation), provisioning services (food and by-products), and supporting services (soil fertility, hydrological flow, nutrient cycling, and soil formation).ResultsThe results indicated that the total economic value of ecosystem services ranged from US$ 1238 to 1688 ha−1 year−1. The marketed (primary production) and non-marketed ecosystem services values ranged from 66–89 to 11–34% of the total, respectively. Valuation of some of the ecosystem services such as cultural services, biodiversity, and gas regulation, which may play a significant role in total ecosystem services, has not been made due to non-availability of data and appropriate methodology for rice ecosystem. Different values of parameters can explain the variability in ecosystem services among the agro-climatic zones in eastern India. Clustering of locations based on variability of ecosystem services helps in identifying intervention points for sustaining and improving ecosystem services, while permitting sustainable agro-ecological intensification. The highest total economic gap between ES value and farm income was found in the north central plateau zone (US$ 1063 ha−1 year−1) and the lowest in the north western plateau zone (US$ 670 ha−1 year−1).ConclusionWe suggest various measures to reduce the economic gap, including payments for ecosystem services for rice farming for sustainability of the ecosystem and agricultural development, while ensuring reliable farm income.

Transformation of continental lithospheric mantle beneath the East African Rift: constraints from platinum-group elements and Re–Os isotopes in mantle xenoliths from Ethiopia

The behavior of sub-continental lithospheric mantle (SCLM) in extensional settings, up to successful rifting, plays an important role in geodynamics and in the global carbon cycle, yet the underlying processes and rates of lithosphere destruction remain poorly constrained. We determined platinum-group element (PGE: Os, Ir, Ru, Pt, and Pd) abundances and Re–Os-isotope systematics for well-characterized mantle xenoliths hosted in Cenozoic basalts from the northwestern plateau (Gundeweyn area) and southern rift zone (Dillo and Megado areas) of Ethiopia to provide new insights on the nature and timing of processes leading to the formation and transformation of the off-cratonic lithospheric mantle beneath the East Africa rift system (EARS). The whole-rock PGE concentrations are highly variable, with total PGE abundances ranging from 6.6 to 12.6 ppb for Gundeweyn, 11.5 to 23.3 ppb for Dillo, and 9.9 to 19.4 ppb for Megado mantle xenoliths. The 187Os/188Os ratios of the whole-rock mantle xenoliths vary from 0.1180 to 0.1287 for Gundeweyn, 0.1238 to 0.1410 for Dillo and 0.1165 to 0.1277 for Megado, compared to 0.130 for the Afar plume and ≥ 0.14 for the Kenya plume, with Re depletion ages up to 1.45 Ga for Gundeweyn, 0.64 Ga for Dillo, and 1.65 Ga for Megado mantle xenoliths. The regional differences between refertilizing agents recorded in mantle xenoliths from the plateau area and the rift systems reflect distinct tectonomagmatic settings: (1) low PGE abundances, with some retention of low 187Os/188Os in Gundeweyn peridotites, are ascribed to scavenging by early small-volume oxidizing melts, generated in the convecting mantle ahead of the arrival of the Afar plume. (2) Percolation of late-stage silicate/basaltic melts, associated with the arrival of hot mantle plume and lithosphere thinning in the rift setting, locally led to refertilization and sulfide precipitation and partial replenishment of the PGE (Dillo), with convecting mantle-like 187Os/188Os. Local enclaves of older, cryptically metasomatised mantle with unradiogenic Os (Megado) attest to the heterogeneous nature of melt–peridotite interaction at this stage (pervasive vs. focused melt flow). Highly depleted abundances of the compatible PGE are characteristic of SCLM affected by incipient rifting and percolation of oxidizing melts, here associated with the Afar and Kenya plume beneath the East Africa rift, and may be precursors to advanced degrees of lithosphere destruction/transformation.

800-kyr land temperature variations modulated by vegetation changes on Chinese Loess Plateau

The complicity of long-term land surface temperature (LST) changes has been under investigated and less understood, hindering our understanding of the history and mechanism of terrestrial climate change. Here, we report the longest (800 thousand years) LSTs based on distributions of soil fossil bacterial glycerol dialkyl glycerol tetraethers preserved in well-dated loess-paleosol sequences at the center of the Chinese Loess Plateau. We have found a previously-unrecognized increasing early and prolonged warming pattern toward the northwestern plateau at the onset of the past seven deglaciations, corresponding to the decrease in vegetation coverage, suggesting underlying surface vegetation or lack of has played an important role in regulating LSTs, superimposed on the fundamental global glacial–interglacial changes. Our results support that LSTs in semi-humid and semi-arid regions with little vegetation will be more sensitive to the anticipated global temperature rise, while improving vegetation coverage would reduce LSTs and thus ecological impacts.

Using Ambient Noise to Image the Northern East African Rift

AbstractThe northern East African Rift (EAR) is a unique location where we observe continental rifting in the Main Ethiopian Rift (MER) transitioning to incipient seafloor spreading in Afar. Here we present a 3‐D absolute shear wave velocity model of the crust and uppermost mantle of the northern EAR generated from ambient noise tomography. We generate 4,820 station pair correlation functions, from 170 stations (present over 12 years), which were inverted for phase velocity from 8–33 s period and finally for 3‐D absolute shear velocity structure to 60‐km depth. Everywhere in the uppermost mantle, shear velocity is slower than expected for a mantle peridotite composition (<4.1 km/s). This suggests the presence of pervasive partial melt, with focused upwelling and melt storage beneath the MER, where the slowest velocities (3.20 km/s ± 0.03) are observed. Average crustal shear velocity is faster beneath Afar (3.83 km/s ± 0.04) than the MER (3.60 km/s ± 0.04), albeit Afar has localized slow velocities beneath active volcanic centers. We interpret these slow‐velocity regions (including the MER) as magmatic intrusions and heating of the crust. Beneath the northwestern plateau, crustal velocities are laterally heterogeneous (3.3–3.65 ± 0.05 km/s at 10 km), suggesting a complex geological history and inhomogeneous magma distribution during rift development. Comparison between the MER and Afar allows us to draw conclusions between different stages of rifting. In particular, the MER has the slowest crustal velocities, consistent with longer magma residence times in the crust, early during the breakup process.

Crustal thickness estimates beneath four seismic stations in Ethiopia inferred from p-wave receiver function studies

Moho depths beneath four stations of the Ethiopian Seismic Station Network (ESSN) are estimated from P-wave receiver functions (RF). We used high quality seismic data recorded at ANKE (Ankober), DILA (Dilla), HARA (Harar) and SEME (Semera) stations for earthquakes located at epicentral distances ranging from 30 to 100° with magnitude mb ≥ 5.5. We applied a frequency domain deconvolution technique to remove source and propagation path effects from the earthquakes waveforms to make the RFs dependent only on the structure beneath the seismic stations. The minimum number of teleseismic earthquakes used is 14 for HARA while the maximum is 39 for SEME station. A linearized-iterative inversion is applied on the generated radial component of the receiver functions to obtain P-wave velocity models beneath the stations. We achieved a reasonably good fit between the observed and synthetic RFs, which demonstrated the high quality of the inversion process. From the obtained models we estimated Moho depths of 26 ± 2 km for SEME, 36 ± 2 km for DILA, 38 ± 2 km for HARA and 42 ± 1.7 km for ANKE. The lowest Moho depth is observed at Semera station which implies a thinned crust while the highest crustal thickness is observed at Ankober, which lies along the North western plateau margin. Our results agree with previous observations which strengthen the hypothesis that Moho depths estimated for stations that lie within the rift and rift margins are lower than those located in the plateaus. Our RFs inversions show a low velocity gradient at about 16 km depth at Semera station, interpreted as evidence for lower crustal storage of partial melt.

Genetic diversity of Haemaphysalis qinghaiensis (Acari: Ixodidae) in western China.

Haemaphysalis qinghaiensis as an endemic species in China mainly infests domestic animals and causes great harm to animals and humans in Northwestern plateau. However, there is no information about genetic diversity within the recently established populations of this tick species. Therefore, the present study analyzed the fragments of mitochondrial 16S rDNA, COI and the nuclear gene ITS1 of 56 H. qinghaiensis ticks across four regions of China which are main endemic areas of this species. Analysis showed 98.1-100% (16S rDNA), 97.9-100% (COI), 99.7-100% (ITS1) identity within individuals. For these sequences, 9, 15 and 8 haplotypes were found for 16S rDNA, COI and ITS1, respectively. Ticks from Yongjing were the most variable group, followed by Lintan, Huangyuan, and Tianzhu. Based on parallel analysis of the mitochondrial and nuclear genetic diversity of H. qinghaiensis, our results indicated that mitochondrial markers (especially COI) were much more useful than nuclear ITS for intraspecific genetic variability analysis.