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作者： Francis Levi A.DURANO Jon Marx SARMIENTO larry N.DIGAL Pedro A.ALVIOLA IV School of Management University of the Philippines MindanaoDavao City 8000Philippines

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation

关键词： Cocoa farms Cobb-Douglas production function Elevation Philippines Stochastic frontier analysis Technical efficiency

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Importance of Stewards and Other Protection Efforts for Conservation of Red Knots (Calidris canutus rufa) and Other Shorebirds on Delaware Bay, New Jersey

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Natural Science 2024年第9期16卷 162-182页

作者： Joanna Burger Amanda Dey larry Niles Division of Life Sciences Rutgers University Piscataway NJ USA Wildlife Restoration Partnerships 109 Market Lane Greenwich NJ USA

Understanding the factors that contribute to population stability in long-distance migrant birds is increasingly important, particularly given global climate change, sea level rise, and loss or disturbance at essential habitats. While the populations of most shorebirds are declining worldwide, those that migrate through Delaware Bay, New Jersey and Delaware, are declining at the most rapid rate despite conservation efforts. In this paper, we 1) provide background information on population declines of red knots (Calidris canutus rufa) using Delaware Bay, threats to their foraging, and efforts to reduce threats, 2) summarize briefly our studies of the effects of human activities on knots and other shorebirds, 3) present data on management efforts to protect knots and other shorebirds from the activities of people, and 4) discuss the efficacy of such efforts (usually referred to as “decreasing the effect of human disturbances”). The Shorebird Project on Delaware Bay is over 25 years old and provides long-term data to help assess the status of shorebird numbers, particularly for red knot, as well as the density of horseshoe crabs (Limulus polyphemus) and their eggs. Red knots have continued to decline even more precipitously in the last few years, presenting cause for concern. Protective efforts have been successful in reducing human disruption on the N.J. Delaware Bay beaches, but the lack of uniformity in implementation across the New Jersey side, and across the whole Bay have hampered further improvements. Implementation of signs, fencing, and stewards on some beaches significantly enhanced the use of these beaches by red knots, determined by examining the use of beaches pre- and post-implementation. Implementation of fencing and stewards had the greatest effect. From 1986 to 2018, there was a significant shift in the percent of Delaware Bay red knots using the NJ side, where protection efforts had been implemented on many of the beaches. Merely restricting access (w

关键词： Red Knot Calidris canutus rufa Conservation Beach Monitors Human Disturbance Habitat Restoration Management Stewards Education Population Declines Coastal

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Advanced Photonics:Thank you for five wonderful years

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Advanced Photonics 2024年第1期6卷 5-5页

作者： Anatoly V. Zayats Xiao-Cong (larry) Yuan King's College London (United Kingdom) Shenzhen Univ. (China)

As we mark the fifth anniversary of Advanced Photonics,we are filled with immense pride and gratitude for the remarkable journey we have undertaken together with our authors,readers,reviewers,Editorial Board,and *** the past half-decade,the journal has fostered groundbreaking research and facilitated discussions on the most innovative topics of optics and *** is reflected in our current standing as one of the top five journals in optics.

关键词： journal optics discussions

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Assessment of groundwater quantity, quality, and associated health risk of the Tano river basin, Ghana

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Acta Geochimica 2024年第2期43卷 325-353页

作者： Adwoba Kua-Manza Edjah Bruce Banoeng-Yakubo Anthony Ewusi Enoch Sakyi-Yeboah David Saka Clara Turetta Giulio Cozzi David Atta-Peters larry Pax Chegbeleh Water Resources Research Centre Ghana Atomic Energy CommissionAccraGhana Earth Science Department University of GhanaLegonAccraGhana Geological Engineering Department University of Mines and TechnologyTarkwaGhana Department of Statistics University of GhanaAccraLegonGhana Institute of Polar Sciences National Research Council of ItalyVeniceItaly

In the Tano River Basin,groundwater serves as a crucial resource;however,its quantity and quality with regard to trace elements and microbiological loadings remain poorly understood due to the lack of groundwater logs and limited water *** study presents a comprehensive analysis of the Tano River Basin,focusing on three key ***,it investigated the aquifer hydraulic parameters and the results showed signiﬁcant spatial variations in borehole depths,yields,transmissivity,hydraulic conductivity,and speciﬁc *** boreholes were concentrated in the northeastern and southeastern zones,while geological formations,particu-larly the Apollonian Formation,exhibit a strong inﬂuence on borehole *** study identiﬁed areas with high transmissivity and hydraulic conductivity in the southern and eastern regions,suggesting good groundwater avail-ability and suitability for sustainable water ***-ondly,the research investigated the groundwater quality and observed that the majority of borehole samples fall within WHO(Guidelines for Drinking-water Quality,Environmental Health Criteria,Geneva,2011,***://***)***,some samples have pH levels below the standards,although the groundwater generally qualiﬁes as *** study further explores hydrochemical facies and health risk assessment,highlighting the dominance of Ca–HCO3 water *** element analysis reveals minimal health risks from most elements,with chromium(Cr)as the primary contributor to chronic health ***,this study has provided a key insights into the Tano River Basin’s hydrogeology and associated health *** outcome of this research has contributed to the broader understanding of hydrogeologi-cal dynamics and the importance of managing groundwater resources sustainably in complex geological environments.

关键词： Groundwater Unsupervised machine learning technique Hydrochemistry Aquifer hydraulic parameter Health risk

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Petrophysical Evaluation of Cape Three Points Reservoirs

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International Journal of Geosciences 2024年第2期15卷 162-179页

作者： Striggner Bedu-Addo Sylvester Kojo Danuor larry Pax Chegbeleh Department of Physics Kwame Nkrumah University of Science and Technology Kumasi Ghana Department of Earth Science University of Ghana Accra Ghana

The findings of a study to ascertain and assess the petrophysical characteristics of Cape Three Points reservoirs in the Western basin with a view to describe the reservoir quantitatively using Well Logs, Petrel and Techlog. The investigated characteristics, which were all deduced from geophysical wire-line logs, include lithology, porosity, permeability, fluid saturation, and net to gross thickness. To characterise the reservoir on the field, a suite of wire-line logs including gamma ray, resistivity, spontaneous potential, and density logs for three wells (WELL_1X, WELL_2X, and WELL_3X) from the Tano Cape Three Point basin were studied. The analyses that were done included lithology delineation, reservoir identification, and petrophysical parameter determination for the identified reservoirs. The tops and bases of the three wells analysed were marked at a depth of 1203.06 - 2015.64 m, 3863.03 - 4253.85 m and 2497.38 - 2560.32 m respectively. There were no hydrocarbons in the reservoirs from the studies. The petrophysical parameters computed for each reservoir provided porosities of 13%, 3% and 11% respectively. The water saturation also determined for these three wells (WELL_1X, WELL_2X and WELL_3X) were 94%, 95% and 89% respectively. These results together with the behaviour of the density and neutron logs suggested that these wells are wildcat wells.

关键词： Petrophysical Cape Three Points Reservoirs

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Temporal variability and sources of PFAS in the Rio Grande,New Mexico through an arid urban area using multiple tracers and highfrequency sampling

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Emerging Contaminants 2024年第3期10卷 205-220页

作者： Kimberly R.Beisner Rebecca E.Travis David A.Alvarez larry B.Barber Jacob A.Fleck Jeramy R.Jasmann U.S.Geological Survey 6700 Edith Blvd NEAlbuquerqueNM87113USA U.S.Geological Survey 4200 New Haven RoadColumbiaMO65201USA U.S.Geological Survey 3215 Marine St.BoulderCO80303USA U.S.Geological Survey 6000 J St.Placer Hall.SacramentoCA95819USA

Per-and polyfluoroalkyl substances(PFAS)are ubiquitous in the environment but sources are not well defined for temporal and spatial aspects within an urban environment,and especially for an arid urban environment subject to seasonal short term high-intensity precipitation events.A focused diel sampling was conducted in the summer of 2021 to assess the temporal and spatial variability of PFAS in the Rio Grande near Albuquerque,New Mexico and showed an order of magnitude increase of PFAS as it flows through the Albuquerque urban *** samples were collected at two different locations on the Rio Grande in addition to wastewater treatment plant(WWTP)effluent that discharges directly to the Rio Grande between the sampling ***-term high-intensity precipitation events occurred during the study period and mobilized PFAS from urban *** organic matter composed of tryptophan-like organic substances and refined fuel and fuel byproducts,characteristic of an urban signature,were also related to the precipitation *** PFAS in discharge from the WWTP was consistent over a 24-h period with slight differences in some *** presence on the Rio Grande downstream of the WWTP was evidenced by a gadolinium anomaly as well as increases in several other trace elements,total dissolved nitrogen,and fluorescence indicators,in addition to *** varied depending on source contribution,where urban runoff was associated with PFOA,PFOS,and PFBA,whereas PFHxA and PFPeA were associated with wastewater *** addition,passive polar organic chemical integrative samplers(POCIS)using hydrophilic-lipid balance(HLB)sorption media were deployed for a month at two locations on the Rio Grande to assess longer term PFAS *** POCIS results show some compounds(PFPeA and PFHpA)were greater than the average concentration from discrete samples,whereas other compounds(PFHxA,PFOA,PFDA,and PFNA)were lower in the POCIS,and PFOS was very simila

关键词： wastewater Rio runoff

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