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The US wood pellet exports--mostly to Europe, Japan, and South Korea--comprised 85 percent of its wood pellet production in the past 20+ years. In this article, we estimate the regional excess supply of wood pellets in the United States using annual data from 1996 to 2021. We use Seemingly Unrelated Regression (SUR) analysis in a profit maximization framework for the South, North, and West regions of the United States. We also include some clean energy policies of the European Union (EU) to examine their potential impact on US wood pellet export volume. Our results show that after application of the low-carbon energy target in the EU, the export volume of the United States has increased, especially in the South region. Elasticity of excess wood pellet supply from the United States was approximately 0.15 in all three regions, and interest rates and energy costs have negative impacts on regional excess supply. Therefore, the recent increase in interest rates and energy costs could slow down the growth of excess supply of wood pellets in the United States., Demand for clean energy, including bioenergy, has been growing as a result of concerns about global environmental sustainability. Wood pellets are a new forest biomass for bioenergy production and a [...]

Beta-1,3-glucan recognition protein (βGRP) is an important pattern recognition receptor, which induces an immune response by recognizing and binding the pathogenic bacteria. In this study, we identified two βGRPgenes in S. furcifera, βGRP1and βGRP2. Both βGRP1 and βGRP2 proteins have a glycosyl hydrolases family 16 (GH16) domain  and a concanavalin A-like lectin/glucanase domain near the C-terminal. Quantitative polymerase chain reaction (qRT-PCR) analysis showed that the transcript levels of βGRP1and βGRP2in the fat body and gut were higher than those in other tissues. Furthermore, both were upregulated in response to challenges with Escherichia coliand Staphylococcus aureus. Recombinant βGRP1 and βGRP2 had a strong affinity for E. coliand S. aureusand caused bacteria to agglutinate. However, the results of the CCK-8 and bacteriostatic zone methods showed that recombinant βGRP1 and βGRP2 inhibited S. aureusbut did not inhibit the growth of E. coli.Moreover, the silencing of βGRP1or βGRP2using dsRNA significantly downregulated the expression of the Toll pathway gene Dorsalafter S. aureuschallenge, while it did not affect the Imd pathway gene Relish.

Abstract In this article we discuss the impact of the recent housing crisis and economic recession on the southern US softwood sawmill industry. We use the first difference model to [...]

Abstract Although the hardwood timber market is an important segment of the forest industry in the United States, little attention has been paid to modeling hardwood stumpage and lumber markets. [...]

Abstract The current status of southern yellow pine (SYP) lumber use in the Japanese housing and construction markets is reviewed and compared with other Asian markets. We look into the [...]

Abstract In this article, we present estimates of regional softwood lumber supply functions in the United States using annual time series data for 1959 to 2009. Seemingly unrelated regression is [...]

Abstract In this study, we use a nonparametric programming approach to estimate technical efficiency and total factor productivity (TFP) growth of sawmill industries in various regions of the United States [...]

Peptidoglycan recognition proteins (PGRPs) participate in insect defense against bacterial pathogens by recognizing bacterial cell wall peptidoglycans (PGNs). Here, we identified the PGRP-LBgene in the white-backed planthopper Sogatella furcifera(SfPGRP-LB). SfPGRP-LB is a secreted protein with a typical PGN-binding domain and five conserved amino acid (aa) residues required for amidase activity. Expression analysis showed that the SfPGRP-LBtranscript levels were significantly higher in the midgut than in other tissues. Silencing SfPGRP-LBwith dsRNA significantly downregulated the expression of Toll pathway genes Tolland Dorsaland Imd pathway genes Imdand Relishafter Escherichia colichallenge. However, only Tolland Dorsalexpressions were downregulated after Staphylococcus aureuschallenge. E. coliand S. aureuschallenges rapidly and strongly upregulated SfPGRP-LBexpression. Recombinantly expressed SfPGRP-LB (rSfPGRP-LB) had strong affinities for E. coliDap-type PGN and S. aureusLys-type PGN and agglutinated the bacteria. However, rSfPGRP-LB inhibited S. aureusbut not E. coligrowth. Furthermore, rSfPGRP-LB had amidase activity, degraded Lys-type PGN, and destroyed S. aureuscell walls but had no such effects on E. coliDap-type PGN. Thus, SfPGRP-LB recognizes and binds various bacterial PGNs but only has amidase activity against Lys-type PGN.

The pre‐Cenozoic structural pattern of Asia has had a strong impact on the localization and propagation of the Cenozoic deformation that gave birth to the Tibetan Plateau. Northern Tibet represents a key area to decipher the structural and kinematic links between the Mesozoic and Cenozoic evolution of Tibet. Nonetheless, the Mesozoic tectonic setting of the North Tibet and the role that the Paleozoic inherited Altyn Tagh Fault (ATF) shearing zone played in controlling the regional tectonic pattern during the deposition of the Mesozoic strata remain controversial. This study is based on seismic reflections, isopach maps of the Mesozoic strata in the Qaidam Basin, and provenance analysis using detrital zircon geochronological and heavy mineral contents. Seismic reflections and isopach maps demonstrate that sustained strike‐slip motion along the ATF during the Early to Late Jurassic induced transtensional basin formation. Further away from the main ATF (eastern parts of the Qilian Shan and the northern Qaidam Basin), transtension also occurred along major faults, although local transpression developed in relay zones. Rotation in the regional stress field induced compression and basin inversion during the Late Jurassic to Early Cretaceous. The Cenozoic sedimentary rocks in these regions display widespread growth strata and angular unconformities characteristic of compression. This is consistent with topographic changes marked by sediment source variation evidenced by detrital zircon geochronology and heavy mineral analysis. We propose that the mechanism driving the Jurassic extension/transtension in North Tibet could be related to far‐field effects of subduction processes along the southern margins of the continent. Mesozoic strike‐slip motion along the Altyn Tagh Fault (ATF) shearing zone controlled the formation of transtensional basinsChange in the direction of regional stress field occurred during the Late Jurassic‐Early CretaceousThe Qilian Shan and the Qaidam Basin were completely inverted under a N‐S or NE‐SW oriented compression during the Early Cenozoic

The Paleogene Lulehe Formation marks the onset of deposition in the Qaidam basin and preserves evidence of the initial topographic growth of northern Tibet. However, limited outcrops impede understanding of the sedimentary features of the Lulehe Formation as well as the tectonic relationship between the basin and surrounding topography. To fill this gap, we investigated core samples along the basin margin and conducted flexural modeling to estimate the topographic load of the Qilian Shan and Eastern Kunlun Shan during the deposition of the Lulehe Formation. Core samples reveal that the Lulehe Formation mainly consists of distal fluvial to marginal lacustrine deposits and proximal fluvial deposits along the southern margin of the basin while characterized by proximal alluvial fan deposits along the northern margin of the basin. Together with evidence for faulting shown on the seismic profiles, we infer that simultaneous deformation within the Qilian Shan and Altyn Tagh Shan during the Paleogene resulted in accumulation of coarse detrital deposits in the northwestern and northeastern Qaidam basin. The simultaneous deformation within the Altyn Tagh Shan and Qilian Shan since the Paleogene supports the idea that deformation in these two regions is kinematically linked. One‐ and two‐load beam flexural modeling indicates that the topographic load generated by both the Eastern Kunlun Shan and the Qilian Shan is responsible for the subsidence of the Qaidam basin during deposition of the Lulehe Formation. Our results highlight the initial relative high topography in the northern Tibetan plateau during the early Cenozoic. We carry out flexural modeling to estimate the initial topographic load of the Qilian Shan and Eastern Kunlun ShanLulehe Formation consists of distal fluvial‐marginal lacustrine and proximal fluvial‐alluvial fan deposits along the margins of the basinBoth Qilian Shan and Eastern Kunlun Shan topographic loads account for the initial subsidence of the Qaidam basin

ABSTRACT This paper uses analysis of variance (ANOVA) and regression analysis to study U.S. softwood lumber price volatility between 1980 and 2000, the period that coincides with several episodes of [...]

Two debated age models, with a basal age of ~50 Ma versus ~30 Ma, are proposed for the depositional age of Cenozoic strata within the Qaidam basin result in a diverse understanding of the initial pattern of deformation in the northern Tibetan Plateau. To evaluate these age models, we integrated isopach maps within the basin with published thermochronology data from surrounding ranges to balance the sediments preserved in the basin with materials eroded in the drainage area. When following the traditional ~50 Ma age model, the total volume of material eroded from the surrounding source area is 4.4 ± 0.3 × 105km3. Using instead the ~30 Ma age model for the basal Lulehe Formation and related revisions to the basin chronology, the volume of eroded material is calculated at 3.5 ± 0.2 × 105km3, which provides a better match to the calculated total volume of solid grains that are preserved in the basin (2.8 ± 0.1 × 105km3). However, growth strata revealed in seismic profiles along the Southern Qaidam Thrust suggest reverse‐faulting began during the deposition of Oligocene‐Miocene strata. Following the ~50 Ma age model, the onset time of faulting along the Southern Qaidam Thrust is ~35.5 Ma, consistent with previous thermochronology results. If both age models are correct, then this requires a significant time‐transgressive nature to basin fill that allows for older ages of deposition in the southern part of the basin. This study highlights the need for further effort to determine the depositional age of the strata in the southern and western parts of the Qaidam basin. We balance the sediment volume preserved in the Qaidam basin with material eroded in the surrounding rangesWe tested two competing models of basin fill and erosion commencing 30 and 50 MaOur analysis is consistent with both the 30 and 50 Ma ages suggesting time‐transgressive basin fill

In this paper, we first present a total forest economic value framework from an anthropocentric instrumental value perspective and differentiate gross value, economic value, market value, and valuation of forest ecosystem services. We then argue that some of the demand-side-based non-market valuation approaches only provide an estimate of gross value, not economic value. Thus, strictly speaking, they are not market valuation per se as the supply side is ignored, and as many non-marketable and non-extractive forest ecosystem services are concerned, it is often the supply side – the opportunity costs of resources used to produce them that determine the economic values of these services. Finally, we identify the role of economic valuation of forest ecosystem services in the political market that often allocates resources directly to produce these services.

As an active microwave remote sensing imaging sensor, Synthetic Aperture Radar (SAR) plays an important role in earth observation. Here we establish a SAR system based on the platform of the moon. This will aid large-scale, constant, and long-term dynamic Earth observations to better meet the needs of global change research and to complement the space borne and airborne earth observations. Lunar-based SAR systems have the characteristics of high resolution and wide swath width. The swath width could be thousands of kilometers in the stripe mode and it could cover 40% of earth’s surface with 10 meters or even higher spatial resolution in the scanning mode. Using the simplified observation model, here we quantitatively analyze the spatial resolution and coverage area of lunar-based SAR and simulate the observation on the Qinghai-Tibet plateau and the Amazon plain. The results show that this system could provide near 100% daily coverage of the Qinghai-Tibet plateau, whereas 40% to 70% daily coverage of the Amazon plain. Lunar-based SAR could provide large-scale, long-term and stable time series data in order to support future research of global change.

We have compiled an exhaustive list of timberland investment management organizations (TIMOs) and timberland real estate investment trusts (REITs) and used USDA Forest Service, Forest Inventory Analysis data to quantify their acreage, distribution, dynamics, and management practices. We find that TIMOs and REITs own/manage about 16 million ac or 10% of the timberland across 11 southern states and that they manage these forests in a sustainable fashion in terms of growth-to-removals and reforestation. Furthermore, TIMOs and REITs own/manage more forest plantations than other owners and harvest more hardwood than is grown. Most of the timberland owned and managed by TIMOs and REITs, located mainly in the southern coastal plain and Piedmont regions, were previously owned by forest industry firms.

Abstract:In this study, we analyze the effect of property taxes on changes between agricultural, forestry, Conservation Reserve Program, and developed land uses in Louisiana. We estimate a random parameters logit model of land-use conversion from the National Resources Inventory plot data. Our results indicate that land-use changes are inelastic with respect to property taxes. Simulation shows that current use valuation policy, while slowing down development of rural lands, also affects changes between rural land uses.

Using the online citation service available through the Institute for Scientific Information and publication records, we constructed rankings of 53 North American forestry programs based on (1) total citations to the scholarly contributions of current faculty, (2) citations per research faculty member, (3) total number of publications in five top forestry journals, (4) total number of pages, (5) total number of publications per research faculty member, and (6) total number of page per research faculty member, from January 1997 to December 2001. We then compared these results against a ranking of the top forestry schools, based on perceived research profile, as indicated by survey responses from deans and department heads.

Mitochondrial AtFtsH4 protease is one of four inner membrane-bound FtsH proteases in Arabidopsis. We found that the loss of AtFtsH4regulates Arabidopsisdevelopment and architecture by mediating the peroxidase-dependent interplay between hydrogen peroxide (H2O2) and auxin homeostasis. These morphological changes were correlated with elevated levels of both hydrogen peroxide and peroxidases, which suggested that ftsh4–4plant was related to the oxidative stress, and that the architecture was caused by the auxin homeostasis perturbation. This view was supported by the expression levels of several auxin signaling genes and auxin binding and transport genes were decreased significantly in ftsh4–4plants. Taken together, our data published in the May issue of Molecular Plant suggests a link between the lack of AtFtsH4 protease, oxidative stress,s and auxin homeostasis to regulate plant growth and development. However, the detail molecular mechanisms of AtFtSH4 regulating oxidation stress and auxin homeostasis is unclear. Here, we present evidence that the high level accumulated of H2O2in ftsh4–4may correlates with the decreased mitochondrial respiration genes. We also showed that the decreased auxin level and auxin transport may caused by the inhibition of mitochondrial respiratory chain complexes.