The Aquatic Macroinvertebrates of the White River National Wildlife Refuge

The primary purpose of this study was to survey the diversity of the aquatic macroinvertebrates of the White River National Wildlife Refuge (WRNWR). Determining relative abundance and distributional and seasonal patterns were secondary objectives. No comprehensive investigations of the WRNWR aquatic macroinvertebrates had been conducted previously, and it was hypothesized that this relatively undisturbed area may serve as a refugium. Further, this study provides base line data by which management programs can be composed. Thirty sampling stations were established within the WRNWR. Samples were collected from north to south at a basic rate of five stations per month. Revisit collections were made during the subsequent six month period, providing a total of 60 samples. Each station was sampled on each occasion for 1.4 man hours with a Turtox Indestructible dip net, and specimens were preserved in 70% ethanol. Three black light samples were taken to augment the species list. Of the 15,083 organisms collected, 80.4% were insects while 6.4% were decapod crustaceans, 5.2% were molluscs, 4.5% were isopods and 2.1% were amphipods. Number of taxa collected per station ranged from 8-36, while numerical standing crop ranged from 8-600. Shannon-Wiener diversity values ranged from 1.056-4.717. The most complex aquatic macroinvertebrate communities were found, in general, in the southeastern portion of the refuge. Great diversity here and at a few other stations was correlated with minimal disturbance by human activity. Parts of the WRNWR apparently function as a refugium. Four of the ten leach species collected, and an uncommon beetle, Suphis, were new state records

Multisymplectic geometry, variational integrators, and nonlinear PDEs

This paper presents a geometric-variational approach to continuous and discrete mechanics and field theories. Using multisymplectic geometry, we show that the existence of the fundamental geometric structures as well as their preservation along solutions can be obtained directly from the variational principle. In particular, we prove that a unique multisymplectic structure is obtained by taking the derivative of an action function, and use this structure to prove covariant generalizations of conservation of symplecticity and Noether's theorem. Natural discretization schemes for PDEs, which have these important preservation properties, then follow by choosing a discrete action functional. In the case of mechanics, we recover the variational symplectic integrators of Veselov type, while for PDEs we obtain covariant spacetime integrators which conserve the corresponding discrete multisymplectic form as well as the discrete momentum mappings corresponding to symmetries. We show that the usual notion of symplecticity along an infinite-dimensional space of fields can be naturally obtained by making a spacetime split. All of the aspects of our method are demonstrated with a nonlinear sine-Gordon equation, including computational results and a comparison with other discretization schemes.Comment: LaTeX2E, 52 pages, 11 figures, to appear in Comm. Math. Phy

The tension between fire risk and carbon storage: evaluating U.S. carbon and fire management strategies through ecosystem models

Fire risk and carbon storage are related environmental issues because fire reduction results in carbon storage through the buildup of woody vegetation, and stored carbon is a fuel for fires. The sustainability of the U.S. carbon sink and the extent of fire activity in the next 100 yr depend in part on the type and effectiveness of fire reduction employed. Previous studies have bracketed the range of dynamics from continued fire reduction to the complete failure of fire reduction activities. To improve these estimates, it is necessary to explicitly account for fire reduction in terrestrial models. A new fire reduction submodel that estimates the spatiotemporal pattern of reduction across the United States was developed using gridded data on biomass, climate, land-use, population, and economic factors. To the authors’ knowledge, it is the first large-scale, gridded fire model that explicitly accounts for fire reduction. The model was calibrated to 1° × 1° burned area statistics [Global Burnt Area 2000 Project (GBA-2000)] and compared favorably to three important diagnostics. The model was then implemented in a spatially explicit ecosystem model and used to analyze 1620 scenarios of future fire risk and fire reduction strategies. Under scenarios of climate change and urbanization, burned area and carbon emissions both increased in scenarios where fire reduction efforts were not adjusted to match new patterns of fire risk. Fuel reducing management strategies reduced burned area and fire risk, but also limited carbon storage. These results suggest that to promote carbon storage and minimize fire risk in the future, fire reduction efforts will need to be increased and spatially adjusted and will need to employ a mixture of fuel-reducing and non-fuel-reducing strategies

The Effect of Size and Type of Slat Upon the Performance of Growing-Finishing Pigs

On approximately December 1, 1973, the first group of pigs was put on test in the new confinement finishing barn at the SDSU swine research unit. The barn consists of 24 pens with space for 8 pigs per pen or a total of 192 head of pigs. Three different slat types and sizes are included in the building which allow a comparison of pig performance as related to floor type. Ten of the pens have concrete slats 5 inches side, 10 of the pens have concrete slats 8 inches wide and 4 of the pens have 3 1/2 inch aluminum slats. The information in this report in a summary of data and observations during the first year related to slat types

Blood Meal as an Ingredient in Diets for Growing-Finishing Pigs

The present experiment was conducted to obtain further information on the value of blood meal as a partial substitute for soybean meal in diets for growing pigs and to study the availability of lysine in blood meal

High and Low Protein in Diets for Growing Pigs

The objective of this experiment was to evaluate two varieties of oats, a high and a low protein oat, when they were fed as the only grain for growing pigs

High Protein Oats as a Replacement for Corn in Growing-Finishing Swine Diets

The objectives of this experiment were to evaluate the protein quality of Dal oats and to determine the feeding value of this oats when used to replace different levels of corn in diets for growing-finishing swine

Blood Meal as a Protein Supplement for Growing-Finishing Pigs

The objective of the experiment reported herein was determine if blood meal as it is now produced could be used as a partial substitute for soybean meal in diets for growing-finishing pigs

Forest disturbance and recovery: A general review in the context of spaceborne remote sensing of impacts on aboveground biomass and canopy structure

Abrupt forest disturbances generating gaps \u3e0.001 km2 impact roughly 0.4–0.7 million km2a−1. Fire, windstorms, logging, and shifting cultivation are dominant disturbances; minor contributors are land conversion, flooding, landslides, and avalanches. All can have substantial impacts on canopy biomass and structure. Quantifying disturbance location, extent, severity, and the fate of disturbed biomass will improve carbon budget estimates and lead to better initialization, parameterization, and/or testing of forest carbon cycle models. Spaceborne remote sensing maps large-scale forest disturbance occurrence, location, and extent, particularly with moderate- and fine-scale resolution passive optical/near-infrared (NIR) instruments. High-resolution remote sensing (e.g., ∼1 m passive optical/NIR, or small footprint lidar) can map crown geometry and gaps, but has rarely been systematically applied to study small-scale disturbance and natural mortality gap dynamics over large regions. Reducing uncertainty in disturbance and recovery impacts on global forest carbon balance requires quantification of (1) predisturbance forest biomass; (2) disturbance impact on standing biomass and its fate; and (3) rate of biomass accumulation during recovery. Active remote sensing data (e.g., lidar, radar) are more directly indicative of canopy biomass and many structural properties than passive instrument data; a new generation of instruments designed to generate global coverage/sampling of canopy biomass and structure can improve our ability to quantify the carbon balance of Earth\u27s forests. Generating a high-quality quantitative assessment of disturbance impacts on canopy biomass and structure with spaceborne remote sensing requires comprehensive, well designed, and well coordinated field programs collecting high-quality ground-based data and linkages to dynamical models that can use this information