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Mid-rotation silvicultural treatments (MRT) are commonly applied to loblolly pine (Pinus taeda L.) plantations in the southeastern United States to improve pine productivity. Competing vegetation is often present in operational plantations and limits site resource availability. The benefits of MRT for pine productivity are well known, but competing vegetation growth has not been extensively studied. Pine and competing vegetati...
Capacity of deep‐sea corals to obtain nutrition from cold seeps aligned with microbiome reorganizationNARA Subscribed
Cold seeps in the deep sea harbor various animals that have adapted to utilize seepage chemicals with the aid of chemosynthetic microbes that serve as primary producers. Corals are among the animals that live near seep habitats and yet, there is a lack of evidence that corals gain benefits and/or incur costs from cold seeps. Here, we focused on Callogorgia delta and Paramuricea sp. type B3 that live near and far from visual si...
The Clutter-Jones (CJ) stand survival model has been widely used for the projection of the reduction in trees per unit area in a forest stand over time. To better understand this well-recognized model, we introduced a varying-parameter formulation as an alternative to its original difference equation form, where plot-specific effects are presented explicitly. This new parameterization turns out to be a type of Richards (genera...
Spatial variability of crop responses to agronomic inputs in on-farm precision experimentationNARA Subscribed
Within-field variability of crop yield levels has been extensively investigated, but the spatial variability of crop yield responses to agronomic treatments is less understood. On-farm precision experimentation (OFPE) can be a valuable tool for the estimation of in-field variation of optimal input rates and thus improve agronomic decisions. Therefore, the objectives of this study were to investigate the spatial variability of...
Stem profile needs to be modeled with an accurate taper equation to produce reliable tree volume assessments. We propose a semiparametric method where few a priori functional form assumptions or parametric specification are required. We compared the diameter and volume predictions of a penalized spline regression (P-spline), P-spline extended with an additive dbh-class variable, and six alternative parametric taper equations i...
An Empirical Examination of Dominant Height Projection Accuracy Using Difference Equation ModelsNARA Subscribed
Site index models developed using the difference equation method, otherwise known as the algebraic difference approach (ADA) along with its generalization (GADA), play an important role in forest growth and yield modeling for operational use. Their projection accuracy tends to be reduced over increasing time intervals, a common modeling phenomenon not yet well understood. In this study, dominant height projections given one si...
Whole Stand Volume and Green Weight Equations for Loblolly Pine in the Western Gulf Region of the United States through Age 15NARA Subscribed
Three whole stand equations were evaluated for best prediction performance of loblolly pine volume and green weight in three physiographic regions of the Western Gulf through age 15 using remeasured permanent research plots from a spacing study. The equations evaluated are two nonlinear forms of the Schumacher yield equation that predict yield from dominant height, stand basal area, and age with or without stand tree density,...
The behaviour and recovery of juvenile lemon sharks Negaprion brevirostris in response to external accelerometer tag attachmentNARA Subscribed
Behavioural responses of lemon sharks Negaprion brevirostris to a fin‐mounted tag package ( CEFAS G6A tri‐axial accelerometer with epoxied Sonotronics PT4 acoustic transmitter) were measured in a controlled captive environment ( n = 10, total length, L T range 80–140 cm) and in free‐ranging sharks upon release ( n = 7, L T range100–160 cm). No changes were detected in behaviour ( i.e . swimming speed, tailbeat frequency, time...