Proxy For Productivity Research Articles

Climate factors rather than human activities controlled NDVI trends across wet meadow areas in the Andes Centrales of Argentina

In the Andes of southern South America, wet meadows are much more productive than nearby arid areas. Human activities, along with climate variations may reduce the productivity of these ecosystems. However, we do not know what the relative effect of climate and human activities on their degradation status is. Here, we first quantified the degradation extent through the temporal trend of normalized difference vegetation index (NDVI), a proxy of productivity, from 1999 to 2017. We did it in 736 wet meadow areas inserted in three nearby zones with contrasting land management. Second, we analyzed the relationship between NDVI and a large-scale mode of climate variability (El Niño Southern Oscillation, ENSO) and regional climate variables (precipitation and temperature) through a structured climate model. Finally, we evaluated human activities’ effects through the temporal trends in the residuals of the climate model. Independently of land management, NDVI trends were mainly negative and affected 56% of the wet meadow areas. The climate model indicated that NDVI increased under La Niña, cool and wet years. Regarding land management, the degradation level was similar across the contrasted land management. Our results suggest that climate factors rather than human activities influenced the degradation process in these areas.

Does Baseline Serum Androgen Levels Have an Impact on Ovulation Induction Cycle Outcomes by Using Clomifene Citrate Among Infertile Women with Polycystic Ovary Syndrome? A Retrospective Cohort Study

OBJECTIVE: Hyperandrogenism is one of the diagnostic criteria for polycystic ovary syndrome. Women with polycystic ovary syndrome suffer from infertility due to anovulation. Hyperandrogenism results in follicular arrest at the antral stage during folliculogenesis. baseline intrinsic hyperandrogenism affects the success of ovulation induction or not. The relationship between baseline serum androgen levels and ovulation induction cycle outcomes by using clomifene citrate among infertile women with polycystic ovary syndrome has not been investigated thoroughly. STUDY DESIGN: Ovulation induction cycle outcomes of 35 infertile women diagnosed with polycystic ovary syndrome according to Rotterdam criteria who have received 50-100 mg/day clomifene citrate have been evaluated retrospectively. Menstrual cycle day 2-5 serum levels for gonadotropins, androgens, metabolic parameters, and ovulation induction cycle outcomes have been compared between women who have and have not achieved clinical pregnancy following treatment. RESULTS: Serum basal follicular stimulating hormone, LH, E2, fasting cholesterol, glucose, and HOMA-IR levels were comparable between these two groups of patients. Unlike other serum androgens, baseline serum-free testosterone level is significantly lower for patients who have achieved clinical pregnancy following ovulation induction with clomifene citrate. The baseline serum cut-off level for free testosterone to predict clinical pregnancy was 1.94 pg/ml with 75% sensitivity and 67% specificity rates. CONCLUSION: Lower or higher levels of androgenic milieu within the ovaries result in defective folliculogenesis and ovulation failure. Increased serum levels of free testosterone which is a proxy for ovarian androgen production might be a detrimental factor for clinical pregnancy rates of women with polycystic ovary syndrome by impairing proper folliculogenesis.

Near‐bed stratification controls bottom hypoxia in ice‐covered alpine lakes

AbstractIn ice‐covered lakes, near‐bottom oxygen concentration decreases for most of the wintertime, sometimes down to the point that bottom waters become hypoxic. Studies insofar have reached divergent conclusions on whether climate change limits or reinforces the extent and duration of hypoxia under ice, raising the need for a comprehensive understanding of the drivers of the dissolved oxygen (DO) dynamics under lake ice. Using high‐temporal resolution time series of DO concentration and temperature across 14 mountain lakes, we showed that the duration of bottom hypoxia under ice varies from 0 to 236 d within lakes and among years. The variability of hypoxia duration was primarily explained by changes in the decay rate of DO above the lake bottom rather than by differences in DO concentration at the ice onset or in the ice‐cover duration. We observed that the DO decay rate was primarily linked to physical controls (i.e., deep‐water warming) rather than biogeochemical drivers (i.e., proxies for lake or catchment productivity). Using a simple numerical model, we provided a proof‐of‐concept that the near‐bed stratification can be the mechanism tying the DO decay rate to the sediment heat release under the ice. We ultimately showed that the DO decay rate and hypoxia duration are driven by the summer light climate, with faster oxygen decline found under the ice of clearer cryostratified alpine lakes. We derived a framework theorizing how the hypoxia duration might change under the ice of alpine lakes in a warmer climate.

Organic matter accumulation mechanisms in the Wufeng-Longmaxi shales in western Hubei Province, China and paleogeographic implications for the uplift of the Hunan-Hubei Submarine high

Organic matter accumulation exhibits different distribution patterns in time and space and tends to be controlled by many factors. This study investigated the mechanisms that control the accumulation of organic matter in the Xianfeng area of western Hubei Province, South China through sedimentological and geochemical analyses of wellbore samples. The results showed that the total organic carbon (TOC) content, mineral content, and elemental geochemical data of the Wufeng-Longmaxi Formations varied significantly with depth. Based on the sharp changes in the vertical profiles of the TOC content, Gamma-ray, and numerous geochemical parameters, as well as regional stratigraphy, this study divided the section from the Upper Ordovician Wufeng Formation to Lower Silurian Longmaxi Formation into six units (W1, W2, GYQ, L1, L2, and L3). The TOC content was positively correlated with redox proxies (DOPT, VEF, and MoEF) and primary productivity proxies (CuEF and NiEF), and negatively correlated with terrigenous input proxies (Al, K, and Ti). The correlation coefficients suggest that the primary factors affecting organic matter accumulation are redox conditions and paleoproductivity, while terrigenous input is a secondary controlling factor. This study proposed an organic matter accumulation model based on the organic matter characteristics, lithofacies, sedimentary environment, and geological setting of the study area. During the deposition of Unit W1, organic matter was well-preserved owing to the anoxic bottom water environment resulting from strong water mass restriction. During the deposition of Unit W2, the rising sea level led to the development of anoxic-euxinic bottom water conditions, and the joint influence of nutrients from upwelling in the open sea and volcanic eruptions enhanced productivity, resulting in the most intense accumulation of organic matter. Unit GYQ had low TOC content due to low productivity despite anoxic conditions. During the deposition of Unit L1, the uplift of the Hunan-Hubei Submarine High caused the depocenter to shift westward and the sea level in this area to drop, resulting in suboxic bottom water and relatively low productivity in the surface water layer. During the deposition of Unit L2, the regional sea level drop resulted in increased input and dilution of terrigenous clasts, thus leading to low TOC content. During the deposition of Unit L3, continuously enhanced terrigenous input due to climate warming and sea level drop became the major factor controlling the organic matter accumulation. In summary, the main factors controlling the organic matter accumulation differed significantly at different evolutionary stages. Compared with the Jiaoshiba area, the Xianfeng area in western Hubei experienced continuously increased terrigenous input, a less reductive water mass, a significant decrease TOC content, and a westward shift of the depocenter since the early stage of the Longmaxi Formation deposition. These changes may be related to the intense uplift of the Hunan-Hubei Submarine High triggered by the Kwangsian Orogeny. These results provide important implications for the understanding of the accumulation of organic matter in the Wufeng-Longmaxi Formations and paleogeographic changes.

Information and Communication Technologies and Agricultural Production: New Evidence from Africa

While information and communication technologies (ICT) have proven to be useful in boosting agricultural production and productivity, regardless of the geographical location, much of the discussion on ICT and their impact focus on the global north, with deficient literature on the global south. The limited account of the global south shows mixed conclusions on the impact of information and communication technologies on agricultural production, with most studies focusing on crop production, as a proxy for agricultural production, leaving out livestock production. Animated by this concern, this article explores the impact of ICTs on agricultural production (crop and livestock) in Africa using panel data from 32 African countries and the panel autoregressive distributed lag model as the estimation technique. We find that individuals using internet significantly increased crop production in the long run. Specifically, a percentage increase in internet patronage increases crop production by 0.071% but significantly decreases the livestock production index, both in the short and long run. Mobile phone subscriptions had a significant negative impact on crop production in the long run but had a significant positive impact on livestock production in the long run. Fixed phone subscriptions significantly increased crop production in the long run but significantly decreased livestock production index in the long run. The findings show bidirectional causality between crop production and internet patronage, livestock production and individuals using internet, crop production and mobile cellular subscription, crop production and net national income, and rural population and both crop and livestock production. We recommend that governments in Africa increase funding investment in digital technologies to foster increased agricultural production while addressing structural challenges that constrain increased access to digital agricultural technologies. It might be useful if governments in sub-Saharan Africa (SSA) incentivize the telecommunication companies to extend digital coverage to rural areas through tax rebates and holidays to encourage rural inclusion in the digital space to bridge the digital divide.

Critical assessment of U, Ba and Ni as redox and productivity proxies in organic-rich sediments underneath dynamic, highly productive waters

Sediments of the continental shelf anoxic zones of the Benguela upwelling system (BUS) and the Peruvian upwelling system are present-day hotspots of trace element accumulation. However, contribution of the lithogenic trace element fraction and early diagenetic transformation processes are poorly constrained. The identification of source and accumulation mechanisms is necessary for the validation of trace elements as proxies for productivity and redox cycling, notably in highly dynamic upwelling systems such as the BUS. Here, we analyzed redox- and biosensitive elements (U, Ba, Ni), lithogenic tracers (Al, Ti, Zr), total organic carbon (TOC) and P in eleven short sediment cores from the Namibian shelf (ca. 22–25°S) as well as grain size fractionated hinterland samples from the Tsauchab Valley at Sossusvlei (∼25°S). These samples help to constrain the lithogenic trace element contributions, a prerequisite for a realistic interpretation of marine authigenic trace element data. Our findings corroborate previous findings that Zr is a sensitive tracer of the coarse fraction in marine sediment for dust input and/or sediment reworking. Hence, the combined analysis of the coarse fraction (Zr), organic matter, and P enrichments (TOC/P) differentiates between a calm, organic matter-rich central shelf environment and a more energetic phosphorite-rich southern shelf environment. A significant correlation of U with P in cores from the southern shelf corroborates previous findings of U incorporation into apatite, the initial formation of which requires oscillating oxic to sulfidic redox conditions. Non-apatite associated U dominates in the cores from the central shelf, where it is only enriched in the buried, anoxic parts of the sediment. This also supports oscillating oxic to sulfidic redox conditions in surface sediment, where U may be recycled. Hence, U accumulates either (i) in apatite under oscillating oxic to sulfidic conditions or (ii) in buried anoxic sediment sections. This strongly questions the use of U as indicator of suboxic conditions but rather anoxic conditions. While lithogenic fractions of U were negligible, the lithogenic fractions of Ba and Ni were found to be elevated. The calculation of authigenic Ba when accounting for lithogenic Ba from the Sossusvlei fine fractions gives more realistic authigenic Ba values. The high Ba enrichment in the BUS is interpreted as uptake of Ba by diatoms and/or nucleation of barite in P-rich diatom remains, as suggested previously. Given the shallow water depth of the cores, barite formation must already take place in subsurface waters (<50 m water depth) as opposed to previous suggesting greater water depths. The lithogenic background of Ni strongly varies from 23°S to 25°S based on Sossusvlei data and the literature. When authigenic Ni contents are calculated accordingly and plotted versus TOC, more systematic trends are seen (compared to total Ni versus TOC). Essentially all cores show an increase in the authigenic Ni/TOC ratio with sediment depth suggesting better preservation and retention of Ni as compared to TOC consistent with previous observations in sediments from the Peruvian upwelling system. This trend corroborates the use of Ni as a productivity indicator for upwelling sediments.

On the Effects of Consumer Sentiment on House Permits: Asymmetric Evidence From State-Level Data in the United States

Previous studies analyzing the link between the housing market and consumer sentiment focus on the impact of the sentiment on house prices. This paper assesses the impact of consumer sentiment on house permits as a proxy for housing production using a linear model that assumes symmetric effects. Additionally, we consider a nonlinear asymmetric model. We estimate both models using state-level data from each state of the United States and find short-run effects of consumer sentiment on house permits in 31 and long-run effects in 33 states. The comparable numbers by estimating a nonlinear asymmetric model were 42 and 41, respectively. In sum, increased consumer confidence has positive long-run effects on the issuance of house permits in most states.

Mechanisms for the Accumulation of Organic Matter in Sediments of the Middle Permian around Bogda Mountain, Southern Junggar Basin, NW China

The organic-rich shales and mudstones of the Middle Permian are the most important unconventional petroleum targets in the southern Junggar Basin of northwestern China. Although numerous studies have been vigorously conducted on paleoenvironment reconstructions, the organic matter enrichment mechanism is still controversial due to the utilization of problematic geochemical proxies established in early studies. In this study, major and trace elemental compositions, molecular markers, stable carbon isotopic compositions, and organic petrology were used to study multiple factors affecting the accumulation of organic matter in sediments. According to the results, a relatively hydrostatic, brackish, anoxic environment is proposed in the northern periphery of the Bogda Mountain, where the original structure of organic matter could be preserved with non-correlations between the productivity proxies (P and Ba) and TOC. In the western Bogda area, organic-rich sediments were deposited under suboxic conditions, with frequent fluctuation occurring between the top and bottom water columns. The accumulation of organic matter was the result of productivity blooms and rapid sedimentation. This improved study of the enrichment of organic matter in the Middle Permian around the Bogda Mountain can contribute to improved evaluations of the petroleum potential and distinguishing the characteristics of different organic matter enrichment models.

Identification and delineation of groundwater-dependent ecosystems (GDEs) in the Khakea–Bray transboundary aquifer region using geospatial techniques

Identifying and delineating groundwater-dependent ecosystems (GDEs) is critical in understanding their location, distribution and groundwater allocation. However, this information is inadequately understood due to limited available data for most areas where they occur. Thus, this study aims to address this gap using remotely sensed, analytical hierarchy process (AHP) and in situ data to identify and delineate GDEs in the Khakea–Bray transboundary aquifer region. The study tested various spatial-explicit GDE indices that integrates environmental factors that predict occurrence of GDEs. These include the normalized difference vegetation index as a proxy for vegetation productivity and modified normalized difference water index as proxy for moisture availability, land-use and landcover, topographical factors such as slope, topographic wetness index, flow accumulation and curvature. The GDEs were delineated using the weighted overlay tool in a Geographic Information System (GIS) environment. The thematic output layer was then spatially classified into two classes, namely, GDEs and non-GDEs. The results showed that only 1.34% of the area is characterised by GDEs covering 721,908 ha. Overall, identified GDEs were found mostly on a gentle slope on the large portion of shrubland and grassland. The derived GDEs map was then statistically compared with groundwater level (GWL) data from 22 boreholes that occur in the area. Our results indicated that: GDEs are concentrated at the northern, central and south-western part of the study area. The validation results showed significant overlapping of GDEs classes with both the groundwater level (GWL) and rainfall in the study area. The results show a possible delineation of GDEs in the study area using remote sensing and GIS techniques along with AHP and is transferable to other arid and semiarid environments. The results of this study contributes to identifying and delineating priority areas where appropriate water conservation programmes for sustainable groundwater development can be implemented.

Thorium isotope evidence for glacial–interglacial dust storminess and productivity in the North Pacific gyre

The flux of dust deposition to the ocean and its impact on marine biological productivity are outstanding issues of the Earth’s climate system. The North Pacific gyre (NPG) is the Earth’s largest ecosystem and is important for marine nitrogen fixation, which is sensitive to Asian dust-regulated surface nutrient stoichiometry. Meanwhile, it is one of the least studied regions in the global ocean during the late Pleistocene, because of the extremely slow sediment accumulation and lack of biological material preservation. 232Th and 230Th concentrations recorded by hydrogenetic ferromanganese crusts in the deep NPG provide a novel and quantitative proxy of dust deposition and export productivity in this region. For this purpose, we have established an in situ U–Th isotope analytical technique on hydrogenetic ferromanganese crusts collected from the deep NPG. Iron, Mn, and Co of our samples have also been analyzed to constrain the impact of dust dissolution on the Fe geochemical cycle. Remarkably, variability of the 232Th-based dust flux over the last ∼900 ky exhibits a striking resemblance to grain-size records of the Chinese loess deposits and sea-level reconstructions but clearly decouples from the global temperature evolution. On orbital time scales, dust storms over the NPG are apparently sensitive to effects related to continental ice sheet sizes but decoupled from major global cooling during the early glaciation. While our 232Th data indicate a 2- to 3-fold variability of glacial–interglacial dust flux, scavenging of Fe, Mn, and Co in the deep NPG is much less variable through the late Pleistocene. We suggest that variable dust fluxes have a limited impact on the inventory of dissolved Fe in the deep waters of NPG, even though the scavenging of Fe has likely been regulated by glacial–interglacial paleoceanography. The paired 230Th-scavenging-based biological productivity tracks gyre sea surface temperature rather than dust flux during the last glacial cycle. We observe no correlation between dust flux and export productivity in the NPG, indicating that dust-derived Fe is not the productivity-limiting factor on orbital time scales in this region. Instead, these results imply that changes in gyre mixing and mode water formation might have led to increased supply of phosphorous and thus enhanced glacial biological carbon sequestration, with potentially stronger nitrogen fixation under higher eolian input.

Variations of organic matter content and type within the sequence stratigraphic framework of the lacustrine deep-water Dongyuemiao formation, Sichuan Basin, Western China

The organic matter (OM) enrichment patterns and mechanisms in lacustrine deep-water shale successions were controlled by complex geological and biological processes, rather than any single factor. The integration of sedimentology, petrography, geochemistry, and sequence stratigraphy in the study of shale successions is vital to the development of robust paleoenvironmental interpretations and OM enrichment model. Based on a systematic sedimentological, petrographic, and geochemical analysis of three continuous cored wells of the Lower Jurassic Dongyuemiao Formation, Sichuan Basin, within a sequence stratigraphic framework, this study reports the complex geological responses in detrital input, sedimentation rate, benthic redox conditions, primary water column productivity, and OM enrichment pattern that caused by lake-level fluctuation. The results indicate that none of the proxies for detrital input, redox conditions, or productivity exhibit a significant correlation with total organic carbon (TOC) content in sediments. The OM enrichment was regulated by a complex interplay of these three factors, which is a function of relative lake-level fluctuation. In general, detrital input was decreased during lake-level transgression; whereas increased during lake-level regression. Reducing conditions and primary productivity were generally enhanced during lake-level transgression; whereas diminished during lake-level regression. Coupled relationships between lake-level fluctuation, bulk TOC content, and OM types were observed. The bulk TOC content and liptinite proportion in sediments increased gradually during the lake-level transgression. In contrast, the bulk TOC content and liptinite proportion in sediments gradually decreased during the lake-level regression. This general principle applies to both second-order and third-order lake-level fluctuation. Our study demonstrates that the development of a reliable OM enrichment model in lacustrine shale successions requires a comprehensive sequence stratigraphic framework.

Shrub diversity in Mediterranean shrublands: Rescuer or victim of productivity?

AbstractAimsUnravelling the most prevalent causal direction between diversity and function in naturally recovered plant assemblages can greatly improve our understanding of the functional significance of diversity and its applications under the ongoing environmental changes. In this study, we apply a structural equation model framework to unravel the most plausible causal direction in the diversity–productivity relationship in subseral Mediterranean shrub‐dominated communities.MethodsTotal shrub cover (as a proxy of productivity when controlled by the time since land use cessation or the last wildfire), the number of species, and the number of functional types based on the dominant life forms (phanerophytes vs. chamaephytes), and the dominant foliar syndromes (deciduous vs. evergreen, needled vs. broad‐leaved), were sampled in 195 circular plots distributed along an elevation gradient ranging from 400 to 1400 m a.s.l. in the Central Iberian Peninsula. We first explored the distribution of functional types along the elevation gradient using a non‐metric multidimensional scaling (NMDS). Secondly, a structural equation model (SEM) framework using mixed‐effects models was defined to unveil the prevalent causal direction between diversity (species and functional types) and productivity at the landscape scale.ResultsModel selection using the Fisher'sCinformation criterion supported a causal direction from total shrub cover to diversity in this landscape. Interestingly, the best supported model also supported a positive relationship between species richness and the number of functional types, which in turn is driven by the total shrub cover along the elevation gradient.ConclusionsOur results suggest that more species might not necessarily boost productivity. On the contrary, ongoing warming temperatures and aridity, which are characteristic of low elevations compared to highlands, might significantly reduce the number of species (victim rather than rescuer) through deleterious effects on productivity.

Earlier Precipitation Enhances Dryland Annual Primary Production

AbstractClimate change is causing shifts of precipitation seasonality that is anticipated to cause variations in terrestrial primary production over many parts of the world. However, how vegetation production responds differently to shifting seasonal precipitation timing along bioclimate gradients remains unclear. Here, we used two proxies of primary production, namely gross primary production and sun‐induced chlorophyll fluorescence derived from satellite observations over 2001–2020 to investigate the effects of advanced or delayed precipitation on interannual variations in production along a wide range of aridity gradient and vegetation types in China. We found contrasting responses of primary production between dryland and humid ecosystems. In the dryland, earlier precipitation greatly enhanced annual accumulated production, owing to higher soil moisture during the early growing season that often lasted to the late growing season by lagged effect. However, delayed precipitation depressed production throughout growing season because of the decreased ability of vegetation to absorb and utilize light energy, even though water stress was alleviated during late growing season. Conversely, in the humid region, advanced precipitation led to slight decreases of annual production as a result of combined effects of lower radiation and lagged leaf flush during the early growing season. It is necessary to consider the effects of shifting precipitation seasonality on terrestrial primary production as a driver of changes in carbon uptake capacity, especially in dryland.

Влияет ли дополнительное профессиональное обучение на зарплаты российских работников?

Additional vocational training is an important tool for sustaining and enhancing employee productivity. The Russian labour market underwent considerable transformations in response to the quarantine measures introduced in 2020 due to the COVID-19 pandemic. Concurrently, in 2019, Russia initiated mea­sures aimed at fostering additional vocational training. This article focuses on evaluating the role of additional vocational training as a determinant of wages, serving as a proxy for labour productivity. Empirical analyses were conducted using representative microdata from the Russian Longitudinal Monitoring Survey (RLMS HSE) spanning the years 2019 to 2021. The impact of additional vocational training was assessed across va­rious demographic groups, including men and women, individuals with and without higher education, as well as those under 40 and over 40 years of age. To test the robustness of the findings, alternative econometric techniques, such as the least squares method, quantile regression, and the difference-in-differences method, were employed. Results from methods that do not account for individuals’ unobservable abilities indicated a positive influence of additional vocational training on wages. However, the difference-in-differences method revealed no statistically significant effect of additional vocational training on wages during the study period. These findings underscore the importance of addressing potential sources of bias in estimates and understanding data limitations, factors that are critical in selecting the appropriate econometric techniques for analysis.

An alternative approach to estimating agglomeration and productivity using geography, demography and evidence from satellite imagery

ABSTRACT In this article we combine novel geographical, demographic and satellite data with an instrumental variables (IVs) estimation approach to tackle a thorny set of data and econometric issues. Studies of agglomeration effects on economic productivity at the city scale have been growing in popularity in both the literature and the interests of urban policymakers in recent years. Despite growing sophistication in econometric approaches, underlying weaknesses in the quality and availability of data at the city scale have hindered efforts to unravel the endogeneity issues, or circularity between city scale, amenity and productivity. We set out both to extend the agglomeration literature to the case of Australia – which hitherto has been lightly studied in this field – and to take advantage of Australia’s unique geography and reliance on migration to drive population change. We also draw on satellite data measuring night-time luminosity as a proxy for economic productivity. We demonstrate the construction of convincing and robust IVs that proxy for population at the city scale. Our econometric estimates indicate that a 1% increase in city populations causes productivity to be enhanced by 0.24–1.70% on average.

Insights into the deglacial variability of phytoplankton community structure in the eastern equatorial Pacific Ocean using [231Pa/230Th]xs and opal-carbonate fluxes

Fully and accurately reconstructing changes in oceanic productivity and carbon export and their controls is critical to determining the efficiency of the biological pump and its role in the global carbon cycle through time, particularly in modern CO2 source regions like the eastern equatorial Pacific (EEP). Here we present new high-resolution records of sedimentary 230Th-normalized opal and nannofossil carbonate fluxes and [231Pa/230Th]xs ratios from site MV1014-02-17JC in the Panama Basin. We find that, across the last deglaciation, phytoplankton community structure is driven by changing patterns of nutrient (nitrate, iron, and silica) availability which, in turn, are caused by variability in the position of the Intertropical Convergence Zone (ITCZ) and associated changes in biogeochemical cycling and circulation in the Southern Ocean. Our multi-proxy work suggests greater scrutiny is required in the interpretation of common geochemical proxies of productivity and carbon export in the EEP.

The trickle down from environmental innovation to productive complexity

We study the empirical relationship between green technologies and industrial production at very fine-grained levels by employing Economic Complexity techniques. Firstly, we use patent data on green technology domains as a proxy for competitive green innovation and data on exported products as a proxy for competitive industrial production. Secondly, with the aim of observing how green technological development trickles down into industrial production, we build a bipartite directed network linking single green technologies at time t_1 to single products at time t_2 ge t_1 on the basis of their time-lagged co-occurrences in the technological and industrial specialization profiles of countries. Thirdly, we filter the links in the network by employing a maximum entropy null-model. Our results emphasize a strong connection between green technologies and the export of products related to the processing of raw materials, notably crucial for the development of climate change mitigation and adaptation technologies. Furthermore, by looking at the evolution of the network over time, we observe a growing presence of more complex green technologies and high-tech products among the significant links, suggesting an increase in their importance in the network.

Geochemical Characteristics and Organic Matter Accumulation of Wufeng-Longmaxi Shales in the Southeast of the Sichuan Basin of South China

The Upper Ordovician Wufeng Formation and Lower Silurian Longmaxi Formation black shales are the critical targets for shale gas exploration in the Sichuan Basin of South China. The enrichment of organic matter (OM) in shale is the basis for the generation of large-scale shale gas; however, its controlling factors in Wufeng-Longmaxi shales are still under debate, and few studies have focused on the edge of the Sichuan Basin. Based on the mineral composition, total organic carbon (TOC), and systematic inorganic geochemistry analysis of 72 core samples from Wufeng and Longmaxi formations in Well Xike 1, southeastern Sichuan Basin, the sedimentary conditions (palaeoclimate, palaeoredox, and palaeoproductivity) were reconstructed, and the controlling factors of OM enrichment were identified. The mineral compositions are dominated by quartz, clay minerals, calcite, and feldspar, associated with minor dolomite, pyrite, and anhydrite. The TOC contents (0.31%-6.84%, avg. 2.22%) show an upward decreasing trend from the Wufeng Formation to Longmaxi Formation. The chemical index of alteration (CIA) ranges from 65 to 71 (avg. 69), indicating warm and humid climate with moderate weathering. The diagrams of Al2O3-TiO2, TiO2-Zr, Zr/Sc-Th/Sc, La/Th-Hf, and La-Th-Sc jointly indicate the contribution from felsic and intermediate rock weathering. The P/Al, Cu/Al, and Ni/Al ratios suggest that marine paleoproductivity was relatively high in the Wufeng Formation and relatively low to moderate in the Longmaxi Formation. The V/Cr, V/Sc, U/Th, MoEF/UEF, and Corg/P ratios indicate that the bottom water was anoxic during the Wufeng Formation deposition and then fluctuating dysoxic and/or oxic in the overlying Longmaxi Formation. The TOC content was positively correlated with productivity proxies (P/Al, Cu/Al, and Ni/Al) as well as redox proxies (U/Th, V/Cr, MoEF/UEF, and Corg/P), indicating that the OM accumulation in Wufeng-Longmaxi shales is mainly controlled by high productivity and anoxic bottom water conditions.

Tree diversity effects on productivity depend on mycorrhizae and life strategies in a temperate forest experiment.

Tree species are known to predominantly interact either with arbuscular mycorrhizal (AM) or ectomycorrhizal (EM) fungi. However, there is a knowledge gap regarding whether these mycorrhizae differently influence biodiversity-ecosystem functioning (BEF) relationships and whether a combination of both can increase community productivity. In 2015, we established a tree-diversity experiment by growing tree communities with varying species richness levels (one, two, or four species) and either with AM or EM tree species or a combination of both. We investigated basal area and annual basal area increment from 2015 to 2020 as proxies for community productivity. We found significant positive relationships between tree species richness and community productivity, which strengthened over time. Further, AM and EM tree species differently influenced productivity; however, there was no overyielding when AM and EM trees grew together. EM tree communities were characterized by low productivity in the beginning but an increase of increment over time and showed overall strong biodiversity effects. For AM tree communities the opposite was true. Although young trees did not benefit from the presence of the other mycorrhizal type, dissimilar mechanisms underlying BEF relationships in AM and EM trees indicate that maximizing tree and mycorrhizal diversity may increase ecosystem functioning in the long run.

Assessing the benefits of the marine protected area of Punta Coles, southern Peru (south‐east Pacific) on productivity of conspicuous benthic species using pre‐image population analysis

Abstract The coastal marine protected ecosystem at Punta Coles (as a part of the Reserva Nacional de Islas, Islotes y Puntas Guaneras) is located in a highly exploited area in southern Peru and contains several commercial, bioengineering and other benthic species. Pre‐image population analysis was used to estimate the transient values of intrinsic growth rate (r) based on biomass and density time series as a proxy of productivity to assess the effectiveness of protection. The outcomes obtained showed that the gastropods Concholepas concholepas, Fissurella latimartiginata and the tunicate Purya chilensis showed a reduction of productivity during recent years, whilst the sea urchin Loxechinus albus, the barnacle Balanus laevis and the bivalve Semimytilus algosus showed an opposite pattern. Several species exhibited a chaotic dynamic, coinciding with the highest productivity values. In 2016 and 2017, several species exhibited a reduction of their abundance which could be delayed responses explained by changes in oceanographic conditions (reduction of coastal upwelling), La Niña event and illegal harvest. The above notwithstanding, the results suggest that effective protection of benthic species in the protected ecosystem of Punta Coles have been partially accomplished. Therefore, this work could be considered a baseline study, permitting the subsequent monitoring of productivity of the main species inhabiting the coastal area of Punta Coles. Pre‐image population analysis could be used as a complimentary analytical tool since it enables the evaluation of transient population parameters (e.g. productivity) thus aiding population management, conservation and monitoring decisions.