Social and Behavioral Sciences Commons^™

Is Closing The Agricultural Yield Gap A "Risky" Endeavor?, Nicolas Gatti, Michael Cecil, Kathy Baylis, Lyndon Estes, Jordan Blekking, Thomas Heckelei, Noemi Vergopolan, Tom Evans

Geography

CONTEXT: Sub-Saharan Africa (SSA) has the climatic and biophysical potential to grow the crops it needs to meet rapidly growing food demand; however, agricultural productivity remains low. While potential maize yields in Zambia are 9 t per hectare (t/ha), the average farmer produces only 1–2. OBJECTIVE: We evaluate the contribution of responses to weather risk to that gap by decomposing the yield gap in maize in Zambia. While we know that improved seed and fertilizer can expand yield and profit, they may also increase the variance of yield under different weather outcomes, reducing their adoption. METHODS: We use a novel …

Timing And Magnitude Of Drought Impacts On Carbon Uptake Across A Grassland Biome, Andrew Felton, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Although drought is known to negatively impact grassland functioning, the timing and magnitude of these impacts within a growing season remains unresolved. Previous small-scale assessments indicate grasslands may only respond to drought during narrow periods within a year; however, large-scale assessments are now needed to uncover the general patterns and determinants of this timing. We combined remote sensing datasets of gross primary productivity and weather to assess the timing and magnitude of grassland responses to drought at 5 km² temporal resolution across two expansive ecoregions of the western US Great Plains biome: the C₄-dominated shortgrass steppe and …

Synergistic Use Of Remote Sensing And Modeling For Estimating Net Primary Productivity In The Red Sea With Vgpm, Eppley-Vgpm, And Cbpm Models Intercomparison, Wenzhao Li, Surya Prakash Tiwari, Hesham El-Askary, Mohamed Ali Qurban, Vassilis Amiridis, K. P. Manikandan, Michael J. Garay, Olga V. Kalashnikova, Thomas C. Piechota, Daniele C. Struppa

Mathematics, Physics, and Computer Science Faculty Articles and Research

Primary productivity (PP) has been recently investigated using remote sensing-based models over quite limited geographical areas of the Red Sea. This work sheds light on how phytoplankton and primary production would react to the effects of global warming in the extreme environment of the Red Sea and, hence, illuminates how similar regions may behave in the context of climate variability. study focuses on using satellite observations to conduct an intercomparison of three net primary production (NPP) models--the vertically generalized production model (VGPM), the Eppley-VGPM, and the carbon-based production model (CbPM)--produced over the Red Sea domain for the 1998-2018 time period. …

Management Regimes And Its Impact On The Wetland Fisheries Management In Assam, Ganesh Chandra

Ganesh Chandra

Assam is endowed with copious aquatic wealth in the form of beels, swamps, ponds and rivers. The floodplain wetlands (beels) extending over one lakh hectare, constitute the most important fishery resource of the state. The beels are considered as one of the most productive ecosystems owing to their characteristic interactions between land and water system. These wetlands are the common property resource and under different management regimes. These wetlands are under various management regimes, i.e., private management (individuals and groups), fishermen cooperative management, Community-based fisheries management (decentralized management, Government works as facilitator) and open access. Most of the unregistered beels …

Structure And Productivity Of Haloxylon Ammodendron Communities In The Mongolian Gobi, Tamara I. Kazantseva, Nikolay N. Slemnev, Pjotr D. Gunin, Sh. Tsooj

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Communities of Haloxylon ammodendron are widespread in the Mongolian Gobi where they play a significant role in biodiversity preservation. They occupy several main types of habitats, showing differences in density, projective cover, and productivity. Haloxylon ammodendron plays a similar, if not even more important role in the arid zone of Mongolia as the principal forest-making trees in the Northern part of the country. The complex set of quantitative parameters of Haloxylon ammodendron stands studied here in respect to temporal dynamics can serve as an indicator of both the vitality of desert ecosystems, and of environmental change.

Regional Industrial Structure And Agglomeration Economies: An Analysis Of Productivity In Three Manufacturing Industries, Joshua Drucker, Edward Feser

Edward J Feser

We investigate whether a more concentrated regional industrial structure – the dominance of a few large firms in a given industry in a region – limits agglomeration economies and ultimately diminishes the economic performance of firms in that industry, especially small ones. In an application to three industries using establishment-level production functions and a combination of confidential and publicly available data sources, we find a consistently negative and substantial direct productivity effect associated with regional industrial structure concentration and only mixed and relatively weak evidence that agglomeration economies are a mediating factor in that effect.

Regional Industrial Structure And Agglomeration Economies: An Analysis Of Productivity In Three Manufacturing Industries., Joshua Drucker, Edward Feser

Joshua Drucker

Continuous Late Pleistocene Paleoclimate Record From The Southwest African Margin: A Multi-Proxy Approach, Julia Keegan Shackford

Geosciences Theses

Late Pleistocene sediments recovered from ODP Leg 175, Site 1085 are used to generate a high-resolution (500 yr) record of continental climate change in Southern Africa. The location of Site 1085, the SW African continental slope, provides a continuous hemipelagic section with a significant terrigenous component. Terrigenous sediments are transported via fluvial and/or eolian transport mechanisms with MIS 1 being dominated by eolian transport. Analyses, including grain-size, color reflectance, biogenic sediment geochemistry (%CaCO3, %TOC, and C/N), bulk sediment geochemistry, and clay mineralogy, are used to identify continental climate conditions in southern Africa. Analyses indicate glacial/interglacial variation. Median grain-size peaks are …