Nitrogen and harvest impact on warm-season grasses biomass yield

USDA-ARS?s Scientific Manuscript database

Perennial warm-season grasses have drawn interest as bioenergy feedstocks due to their high productivity with minimal amounts of inputs while producing multiple environmental benefits. Nitrogen (N) fertility and harvest timing are critical management practices when optimizing biomass yield of these ...

Switchgrass cultivar, yield, and nutrient removal responses to harvest timing

USDA-ARS?s Scientific Manuscript database

Finite nutrients, such as P (phosphorus) and K (potassium) are remobilized post-growing season in herbaceous feedstocks such as swichgrass (Panicum virgatum L.) as a function of environmental signaling and genotype. However, harvesting early during the maturation process may result in yield reductio...

A Study of Specialty Clones’ Yield Performance in Early and Late Harvests

USDA-ARS?s Scientific Manuscript database

Technical Abstract: A study was conducted on specialty potato breeding lines to examine yield components in an early and late harvest. Upon first examination it was apparent that the early water cutoff had a large effect on total yield. In the early trial only one clone achieved 600 cwt/A of total...

Genetic architecture, inter-relationship and selection criteria for yield improvement in rice (Oryza sativa L.).

PubMed

Yadav, S K; Pandey, P; Kumar, B; Suresh, B G

2011-05-01

This study has been conducted to determine the extent of genetic association between yield of Rice (Oryza sativa L.) and its components. The present experiment was carried out with 40 Rice (Oryza sativa L.) genotypes which were evaluated in a randomized block design with 3 replications during wet season of 2007 and 2008. Results showed that sufficient amount of variability was found in the entire gene pool for all traits studied. Higher magnitude of genotypic and phenotypic coefficients of variation was recorded for seed yield, harvest index, biological yield, number of spikelets per panicle, flag leaf length, plant height and number of tillers indicates that these characters are least influence by environment. High heritability coupled with high genetic advance as percent of mean was registered for seed yield, harvest index, number of spikelets per panicle, biological yield and flag leaf length, suggesting preponderance of additive gene action in the expression of these characters. Grain yield was significantly and positively associated with harvest index, number of tillers per hill, number of panicle per plant, panicle length, number of spikelet's per panicle and test weight at both genotypic and phenotypic levels. Path coefficient analysis revealed that harvest index, biological yield, number of tillers per hill, panicle length, number of spikelets per panicle, plant height and test weight had direct positive effect on seed yield, indicating these are the main contributors to yield. From this study it may be concluded that harvest index, number of tillers per hill, panicle length and number of spikelet per panicle and test weight are the most important characters that contributed directly to yield. Thus, these characters may serve selection criteria for improving genetic potential of rice.

Sensitivity of TRIM projections to management, harvest, yield, and stocking adjustment assumptions.

Treesearch

Susan J. Alexander

1991-01-01

The Timber Resource Inventory Model (TRIM) was used to make several projections of forest industry timber supply for the Douglas-fir region. The sensitivity of these projections to assumptions about management and yields is discussed. A base run is compared to runs in which yields were altered, stocking adjustment was eliminated, harvest assumptions were changed, and...

The summer flow and water yield response to timber harvest

Treesearch

Elizabeth T. Keppeler

1998-01-01

Continuous measurement of streamflow at the Caspar Creek watersheds has led to several analyses of the effects of two harvest methods (selection and clearcut) on summer flows and annual yield. Although all Caspar Creek analyses have indicated an increase in runoff after timber removal, the magnitude and duration of the response depend on the nature and extent of the...

The Impact of Location and Growing Medium on Harvest Yield and Flavor of Basil and Squash Microgreens

NASA Astrophysics Data System (ADS)

Leal, J.; Ventura, C. J.

2016-12-01

The purpose of this experiment is to discover the most efficient, feasible way to produce a high yield of flavorful microgreens within the best growing medium and building location at the Stanford Educational Farm. In recent years, microgreens, young, small edible greens utilized as flavor garnishes for fine dining, have evolved into an immensely profitable market that will continue to expand and prosper. To capitalize on such opportunities, the primary metrics focused upon are harvest yield and flavor of basil and squash microgreens, as they develop in different concentrations of quick root and compost while located in either a greenhouse or lath house. It was hypothesized that if basil and squash microgreens were grown in a mixture of 50% compost and 50% quick root in the greenhouse, then they would produce the greatest harvest yield and maximum amount of flavor. The general experimental protocol includes monitoring the growth of the microgreens, then harvesting directly after the first true leaves begin to emerge. Upon harvest, each set of microgreens are separated into different clear glass jars to place on a small scale for weighing to determine the yield and tasting the leaves to analyze the flavor content. The highest yield of basil (63 grams) developed in a tray of 100% quick root in the lath house, while the greatest yield of squash (51 grams) succeeded in 100% quick root in the greenhouse. Overall however, the basil grew fastest in the greenhouse but tasted stronger in the lath house. Additionally, because the harvest yield and flavor results were so poor in all other locations and growing mediums for squash during the first trial, it cannot be considered a viable microgreen. In the future, more trials should be conducted for greater numbers of trays of microgreens to collect more data. The nutritional value of microgreens should also be explored further to obtain a holistic approach to the value of these plants from seed to harvest to consumption.

Yield and Nutrient Removal by Whole-Tree Harvest of a Young Bottomland Hardwood Stand

Treesearch

John K. Francis

1984-01-01

The yield and nutrient withdrawal by whole-tree harvest of young bottomland hardwoods has heretofore been unknown. In this study of intensive harvest, samples of chipped whole trees and soil from 16 test plots were analyzed for nutrient content. Eighty-two percent of the stems and 59 percent of the dry weight were green ash. The balance was divided among a number of...

Effects of delayed winter harvest on biomass yield and quality of napiergrass and energycane

USDA-ARS?s Scientific Manuscript database

Napiergrass (Cenchrus purpureus Schumach) and energycane (Saccharum hyb.) are high-yielding perennial grasses that are well-suited for biomass production in the southeast USA. The purpose of this study was to determine the effects of delayed winter harvest on biomass yield and quality of these two ...

Use of indexing to update United States annual timber harvest by state

Treesearch

James Howard; Enrique Quevedo; Andrew Kramp

2009-01-01

This report provides an index method that can be used to update recent estimates of timber harvest by state to a common current year and to make 5-year projections. The Forest Service Forest Inventory and Analysis (FIA) program makes estimates of harvest for each state in differing years. The purpose of this updating method is to bring each state-level estimate up to a...

Greenhouse tomato limited cluster production systems: crop management practices affect yield

NASA Technical Reports Server (NTRS)

Logendra, L. S.; Gianfagna, T. J.; Specca, D. R.; Janes, H. W.

2001-01-01

Limited-cluster production systems may be a useful strategy to increase crop production and profitability for the greenhouse tomato (Lycopersicon esculentum Mill). In this study, using an ebb-and-flood hydroponics system, we modified plant architecture and spacing and determined the effects on fruit yield and harvest index at two light levels. Single-cluster plants pruned to allow two leaves above the cluster had 25% higher fruit yields than did plants pruned directly above the cluster; this was due to an increase in fruit weight, not fruit number. Both fruit yield and harvest index were greater for all single-cluster plants at the higher light level because of increases in both fruit weight and fruit number. Fruit yield for two-cluster plants was 30% to 40% higher than for single-cluster plants, and there was little difference in the dates or length of the harvest period. Fruit yield for three-cluster plants was not significantly different from that of two-cluster plants; moreover, the harvest period was delayed by 5 days. Plant density (5.5, 7.4, 9.2 plants/m2) affected fruit yield/plant, but not fruit yield/unit area. Given the higher costs for materials and labor associated with higher plant densities, a two-cluster crop at 5.5 plants/m2 with two leaves above the cluster was the best of the production system strategies tested.

Raising yield potential in wheat: increasing photosynthesis capacity and efficiency

USDA-ARS?s Scientific Manuscript database

Increasing wheat yields to help to ensure food security is a major challenge. Meeting this challenge requires a quantum improvement in the yield potential of wheat. Past increases in yield potential have largely resulted from improvements in harvest index not through increased biomass. Further large...

Effect of harvest dates on yield and nutritive value of eastern gamgrass

USDA-ARS?s Scientific Manuscript database

Yield of 'Pete' eastern gamagrass [Tripsacum dactyloides (L.) L.] was evaluated for 3 yr. Forage samples were harvested at 7-d intervals beginning on May 15 and ending on July 17, during 2000, 2001, and 2002. Samples from 2000 and 2001 were analyzed to determine nutrient composition. Canopy height i...

Effect of harvesting frequency, variety and leaf maturity on nutrient composition, hydrogen cyanide content and cassava foliage yield.

PubMed

Hue, Khuc Thi; Thanh Van, Do Thi; Ledin, Inger; Wredle, Ewa; Spörndly, Eva

2012-12-01

The experiment studied the effect of harvesting frequencies and varieties on yield, chemical composition and hydrogen cyanide content in cassava foliage. Foliage from three cassava varieties, K94 (very bitter), K98-7 (medium bitter) and a local (sweet), were harvested in three different cutting cycles, at 3, 6 and 9 months; 6 and 9 months and 9 months after planting, in a 2-yr experiment carried out in Hanoi, Vietnam. Increasing the harvesting frequency increased dry matter (DM) and crude protein (CP) production in cassava foliage. The K94 variety produced higher foliage yields than the other two varieties. Dry matter, neutral detergent fibre (NDF), acid detergent fibre (ADF) and total tannin content increased with months to the first harvest, whereas CP content decreased. Hydrogen cyanide (HCN) content was lower at the first harvest than at later harvests for all cutting cycles. At subsequent harvests the content of total tannins tended to decline, while HCN content increased (p<0.05). Chemical composition differed somewhat across varieties except for total tannins and ash. Dry matter, NDF, ADF and total tannins were higher in fully matured leaves, while CP and HCN were lower in developing leaves.

Effect of Harvesting Frequency, Variety and Leaf Maturity on Nutrient Composition, Hydrogen Cyanide Content and Cassava Foliage Yield

PubMed Central

Hue, Khuc Thi; Thanh Van, Do Thi; Ledin, Inger; Wredle, Ewa; Spörndly, Eva

2012-01-01

The experiment studied the effect of harvesting frequencies and varieties on yield, chemical composition and hydrogen cyanide content in cassava foliage. Foliage from three cassava varieties, K94 (very bitter), K98-7 (medium bitter) and a local (sweet), were harvested in three different cutting cycles, at 3, 6 and 9 months; 6 and 9 months and 9 months after planting, in a 2-yr experiment carried out in Hanoi, Vietnam. Increasing the harvesting frequency increased dry matter (DM) and crude protein (CP) production in cassava foliage. The K94 variety produced higher foliage yields than the other two varieties. Dry matter, neutral detergent fibre (NDF), acid detergent fibre (ADF) and total tannin content increased with months to the first harvest, whereas CP content decreased. Hydrogen cyanide (HCN) content was lower at the first harvest than at later harvests for all cutting cycles. At subsequent harvests the content of total tannins tended to decline, while HCN content increased (p<0.05). Chemical composition differed somewhat across varieties except for total tannins and ash. Dry matter, NDF, ADF and total tannins were higher in fully matured leaves, while CP and HCN were lower in developing leaves. PMID:25049534

The effect of aspen harvest and growth on water yield in Minnesota

Treesearch

Elon S. Verry

1987-01-01

Annual water yield increased following the clearcutting of a mature aspen forest in years 1-9 and year 14 of subsequent aspen regrowth. Maximum increases of 85, 117, and 88 mm year-l occurred during the first 3 years of regrowth. Increases in streamflow volumes from snowmelt and early spring rains were minimal and more variable after harvest and...

Use of vegetation health data for estimation of aus rice yield in bangladesh.

PubMed

Rahman, Atiqur; Roytman, Leonid; Krakauer, Nir Y; Nizamuddin, Mohammad; Goldberg, Mitch

2009-01-01

Rice is a vital staple crop for Bangladesh and surrounding countries, with interannual variation in yields depending on climatic conditions. We compared Bangladesh yield of aus rice, one of the main varieties grown, from official agricultural statistics with Vegetation Health (VH) Indices [Vegetation Condition Index (VCI), Temperature Condition Index (TCI) and Vegetation Health Index (VHI)] computed from Advanced Very High Resolution Radiometer (AVHRR) data covering a period of 15 years (1991-2005). A strong correlation was found between aus rice yield and VCI and VHI during the critical period of aus rice development that occurs during March-April (weeks 8-13 of the year), several months in advance of the rice harvest. Stepwise principal component regression (PCR) was used to construct a model to predict yield as a function of critical-period VHI. The model reduced the yield prediction error variance by 62% compared with a prediction of average yield for each year. Remote sensing is a valuable tool for estimating rice yields well in advance of harvest and at a low cost.

Use of Vegetation Health Data for Estimation of Aus Rice Yield in Bangladesh

PubMed Central

Rahman, Atiqur; Roytman, Leonid; Krakauer, Nir Y.; Nizamuddin, Mohammad; Goldberg, Mitch

2009-01-01

Rice is a vital staple crop for Bangladesh and surrounding countries, with interannual variation in yields depending on climatic conditions. We compared Bangladesh yield of aus rice, one of the main varieties grown, from official agricultural statistics with Vegetation Health (VH) Indices [Vegetation Condition Index (VCI), Temperature Condition Index (TCI) and Vegetation Health Index (VHI)] computed from Advanced Very High Resolution Radiometer (AVHRR) data covering a period of 15 years (1991–2005). A strong correlation was found between aus rice yield and VCI and VHI during the critical period of aus rice development that occurs during March–April (weeks 8–13 of the year), several months in advance of the rice harvest. Stepwise principal component regression (PCR) was used to construct a model to predict yield as a function of critical-period VHI. The model reduced the yield prediction error variance by 62% compared with a prediction of average yield for each year. Remote sensing is a valuable tool for estimating rice yields well in advance of harvest and at a low cost. PMID:22574057

Harvesting number and timing effects on shoot yield and flavonoid content in American skullcap (Scutellaria lateriflora)

USDA-ARS?s Scientific Manuscript database

Information on optimal management practices for high dry matter and flavonoid yield in American skullcap is lacking. A field experiment was conducted in central Alabama to determine the effect of timing and frequency of harvest on shoot yield and flavonoid content of American skullcap. In the first ...

Effects of Moringa oleifera silage on milk yield, nutrient digestibility and serum biochemical indexes of lactating dairy cows.

PubMed

Zeng, B; Sun, J J; Chen, T; Sun, B L; He, Q; Chen, X Y; Zhang, Y L; Xi, Q Y

2018-02-01

This study investigated the effects of Moringa oleifera (MO) as a partial substitute of alfalfa hay on milk yield, nutrient apparent digestibility and serum biochemical indexes of dairy cows. MO was harvested at 120 days post-seeding. Fresh MO was cut, mixed with chopped oat hay (425:575 on a DM basis), ensiled and stored for 60 days. Sixty healthy Holstein dairy cows were allocated to one of three groups: NM (no MO or control), LM (low MO; 25% alfalfa hay and 50% maize silage were replaced by MO silage) or HM (high MO; 50% alfalfa hay and 100% maize silage were replaced by MO silage). The feeding trial lasted 35 days. The LM and HM diets did not affect dry matter (DM) intake, milk yield or milk composition (lactose, milk fat, milk protein and somatic cell count). The apparent digestibility of DM and NDF was lower for HM group than NM group. Additionally, there were no significant differences in serum biochemical indexes between the LM and NM groups. The HM group had lower serum concentrations of total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol and higher serum concentrations of urea than the NM group. The partial replacement of alfalfa hay (≤50%) and maize silage with MO silage had no negative effects on milk yield, in vivo nutrient apparent digestibility or serum biochemical indexes of lactating cows. © 2017 Blackwell Verlag GmbH.

Peanut peg strength and post harvest pod scavenging for full phenotypic yield over digging date and variety

USDA-ARS?s Scientific Manuscript database

New peanut cultivars are available with very high yield potential and high levels of disease resistance. With rising input costs and shrinking return margins, all efforts must be made to harvest the full yield produced. Peanut crops are susceptible to high levels of pod loss during digging from a ...

[Characteristics of phosphorus uptake and use efficiency of rice with high yield and high phosphorus use efficiency].

PubMed

Li, Li; Zhang, Xi-Zhou; Li, Tinx-Xuan; Yu, Hai-Ying; Ji, Lin; Chen, Guang-Deng

2014-07-01

A total of twenty seven middle maturing rice varieties as parent materials were divided into four types based on P use efficiency for grain yield in 2011 by field experiment with normal phosphorus (P) application. The rice variety with high yield and high P efficiency was identified by pot experiment with normal and low P applications, and the contribution rates of various P efficiencies to yield were investigated in 2012. There were significant genotype differences in yield and P efficiency of the test materials. GRLu17/AiTTP//Lu17_2 (QR20) was identified as a variety with high yield and high P efficiency, and its yields at the low and normal rates of P application were 1.96 and 1.92 times of that of Yuxiang B, respectively. The contribution rate of P accumulation to yield was greater than that of P grain production efficiency and P harvest index across field and pot experiments. The contribution rates of P accumulation and P grain production efficiency to yield were not significantly different under the normal P condition, whereas obvious differences were observed under the low P condition (66.5% and 26.6%). The minimal contribution to yield was P harvest index (11.8%). Under the normal P condition, the contribution rates of P accumulation to yield and P harvest index were the highest at the jointing-heading stage, which were 93.4% and 85.7%, respectively. In addition, the contribution rate of P accumulation to grain production efficiency was 41.8%. Under the low P condition, the maximal contribution rates of P accumulation to yield and grain production efficiency were observed at the tillering-jointing stage, which were 56.9% and 20.1% respectively. Furthermore, the contribution rate of P accumulation to P harvest index was 16.0%. The yield, P accumulation, and P harvest index of QR20 significantly increased under the normal P condition by 20.6%, 18.1% and 18.2% respectively compared with that in the low P condition. The rank of the contribution rates of P

Effect of biweekly shoot tip harvests on the growth and yield of Georgia Jet sweet potato grown hydroponically

NASA Technical Reports Server (NTRS)

Ogbuehi, Cyriacus R.; Loretan, Phil A.; Bonsi, C. K.; Hill, Walter A.; Morris, Carlton E.; Biswas, P. K.; Mortley, Desmond G.

1989-01-01

Sweet potato shoot tips have been shown to be a nutritious green vegetable. A study was conducted to determine the effect of biweekly shoot tip harvests on the growth and yield of Georgia Jet sweet potato grown in the greenhouse using the nutrient film technique (NFT). The nutrient solution consisted of a modified half Hoagland solution. Biweekly shoot tip harvests, beginning 42 days after planting, provided substantial amounts of vegetable greens and did not affect the fresh and dry foliage weights or the storage root number and fresh and dry storage root weights at final harvest. The rates of anion and cation uptake were not affected by tip harvests.

[Effects of ridge and furrow rain harvesting with supplemental irrigation on winter wheat photosynthetic characteristics, yield and water use efficiency in Guanzhong irrigation district].

PubMed

Zhang, Yu; Han, Qing-fang; Cheng, Xue-feng; Yang, Shan-shan; Jia, Zhi-kuan; Ding, Rui-xia; Ren, Xiao-long; Nie, Jun-feng

2015-05-01

A field experiment was conducted to determine the regulation of crop photosynthesis and output and water saving effect under ridge and furrow rain harvesting with supplemental irrigation in Guanzhong irrigation district. The experiment was set with 5 treatments with irrigation at returning green stage, and the widths of both ridge and furrow being 60 cm. T1, T2 and T3 were in the ridge and furrow rain harvesting planting pattern, with the irrigation volumes being 0, 375 and 750 m3 · hm(-2) respectively, T4 was flat planting with irrigation (border irrigation) of 750 m3 · hm(-2) and CK was flat planting without irrigation. Effects on winter wheat photosynthetic organs, photosynthetic rate, yield and water use efficiency, etc. were tested. The results showed that compared with T4, T1, T2 and T3 treatments increased the grain yield by 2.8%, 9.6% and 18.9%, improved the harvest index by 2.0% to 8.5%, advanced the flag leaf chlorophyll content by 41.9% to 64.4% significantly, and improved the 0-40 cm layer soil moisture content by 0.1%-4.6% during the whole growth period. Photosynthetic rates at the flowering and filling stages also increased by 22.3% to 54.2% and -4.3% to 67.2%, respectively. Total water use efficiencies (WUEy) were 17.9%, 10.4% and 15.4% higher than that of T4, and 69.3%, 58.6% and 65.7% higher than that of CK (P < 0.05), respectively, and enhanced precipitation utilization efficiency ( PUE ) by 94.3%-124.5% than CK. Leaf areas of T2 and T3 treatments at each growth stage were significantly higher than that of T4 and CK, irrigation water use efficiencies (IUE) were 119.1% and 18.8% higher than that of T4, respectively. Therefore, it was concluded that ridge and furrow rain harvesting cultivation could maintain higher grain yield than border irrigation without irrigation or with irrigation reduction by 50%. The utilization efficiency of irrigation water under the condition of irrigation reduction by 50% was improved significantly, and the ridge and

Global Food Security Index Studies and Satellite Information

NASA Astrophysics Data System (ADS)

Medina, T. A.; Ganti-Agrawal, S.; Joshi, D.; Lakhankar, T.

2017-12-01

Food yield is equal to the total crop harvest per unit cultivated area. During the elapsed time of germination and frequent harvesting, both human and climate related effects determine a country's' contribution towards global food security. Each country across the globe's annual income per capita was collected to then determine nine countries for further studies. For a location to be chosen, its income per capita needed to be considered poor, uprising or wealthy. Both physical land cover and regional climate helped categorize potential parameters thought to be studied. Once selected, Normalized Difference Vegetation Index (NDVI) data was collected for Ethiopia, Liberia, Indonesia, United States, Norway, Russia, Kuwait and Saudi Arabia over the recent 16 years for approximately every 16 days starting from early in the year 2000. Software languages such as Geographic Information System (GIS), MatLab and Excel were used to determine how population size, income and deforestation directly determines agricultural yields. Because of high maintenance requirements for large harvests when forest areas are cleared, they often have a reduction in soil quality, requiring fertilizer use to produce sufficient crop yields. Total area and vegetation index of each country is to be studied, to determine crop and deforestation percentages. To determine how deforestation impacts future income and crop yield predictions of each country studied. By using NDVI results a parameter is to be potentially found that will help define an index, to create an equation that will determine a country's annual income and ability to provide for their families and themselves.

Harvesting

USDA-ARS?s Scientific Manuscript database

The spindle picker and brush-roll stripper are the two machines used to harvest cotton produced in the United States. Adoption of each harvester type is dictated by regional differences in regard to production environment, production practices, cultivar, and yield. The spindle picker is a selectiv...

Adaptation to high CO2 concentration in an optimal environment: radiation capture, canopy quantum yield and carbon use efficiency

NASA Technical Reports Server (NTRS)

Monje, O.; Bugbee, B.

1998-01-01

The effect of elevated [CO2] on wheat (Triticum aestivum L. Veery 10) productivity was examined by analysing radiation capture, canopy quantum yield, canopy carbon use efficiency, harvest index and daily C gain. Canopies were grown at either 330 or 1200 micromoles mol-1 [CO2] in controlled environments, where root and shoot C fluxes were monitored continuously from emergence to harvest. A rapidly circulating hydroponic solution supplied nutrients, water and root zone oxygen. At harvest, dry mass predicted from gas exchange data was 102.8 +/- 4.7% of the observed dry mass in six trials. Neither radiation capture efficiency nor carbon use efficiency were affected by elevated [CO2], but yield increased by 13% due to a sustained increase in canopy quantum yield. CO2 enrichment increased root mass, tiller number and seed mass. Harvest index and chlorophyll concentration were unchanged, but CO2 enrichment increased average life cycle net photosynthesis (13%, P < 0.05) and root respiration (24%, P < 0.05). These data indicate that plant communities adapt to CO2 enrichment through changes in C allocation. Elevated [CO2] increases sink strength in optimal environments, resulting in sustained increases in photosynthetic capacity, canopy quantum yield and daily C gain throughout the life cycle.

BANR: A Program to Predict Biomass Yield and Nutrient Withdrawal by Harvest of Southern Hardwood Stands

Treesearch

John K. Francis

1986-01-01

Intensive harvest of southern hardwoods can yield biomass in a greatly varied mix. This causes variation in the withdrawal rates of nutrients. A need exists for a computer program to perform biomass and nutrient content calculations on diverse stands. such a program BANR (Biomass And Nutrient Removal) - is described in this paper. It was written for the Hewlett-Packard...

Monitoring Crop Yield in USA Using a Satellite-Based Climate-Variability Impact Index

NASA Technical Reports Server (NTRS)

Zhang, Ping; Anderson, Bruce; Tan, Bin; Barlow, Mathew; Myneni, Ranga

2011-01-01

A quantitative index is applied to monitor crop growth and predict agricultural yield in continental USA. The Climate-Variability Impact Index (CVII), defined as the monthly contribution to overall anomalies in growth during a given year, is derived from 1-km MODIS Leaf Area Index. The growing-season integrated CVII can provide an estimate of the fractional change in overall growth during a given year. In turn these estimates can provide fine-scale and aggregated information on yield for various crops. Trained from historical records of crop production, a statistical model is used to produce crop yield during the growing season based upon the strong positive relationship between crop yield and the CVII. By examining the model prediction as a function of time, it is possible to determine when the in-season predictive capability plateaus and which months provide the greatest predictive capacity.

Growth and yield in natural stands of slash pine and suggested management alternatives

Treesearch

Frank A. Bennett

1980-01-01

Yields are presented by stand age, site index, and stand basal area at the beginning of a growth period. Differences between these yields and those projected 20 and 50 years ago are explained partly by changing definitions of normal or full stocking and partly by changes in forest management. If only pulpwood harvesting is envisioned, fairly high stocking is needed to...

Estimating yields of salt- and water-stressed forages with remote sensing in the visible and near infrared.

PubMed

Poss, J A; Russell, W B; Grieve, C M

2006-01-01

In arid irrigated regions, the proportion of crop production under deficit irrigation with poorer quality water is increasing as demand for fresh water soars and efforts to prevent saline water table development occur. Remote sensing technology to quantify salinity and water stress effects on forage yield can be an important tool to address yield loss potential when deficit irrigating with poor water quality. Two important forages, alfalfa (Medicago sativa L.) and tall wheatgrass (Agropyron elongatum L.), were grown in a volumetric lysimeter facility where rootzone salinity and water content were varied and monitored. Ground-based hyperspectral canopy reflectance in the visible and near infrared (NIR) were related to forage yields from a broad range of salinity and water stress conditions. Canopy reflectance spectra were obtained in the 350- to 1000-nm region from two viewing angles (nadir view, 45 degrees from nadir). Nadir view vegetation indices (VI) were not as strongly correlated with leaf area index changes attributed to water and salinity stress treatments for both alfalfa and wheatgrass. From a list of 71 VIs, two were selected for a multiple linear-regression model that estimated yield under varying salinity and water stress conditions. With data obtained during the second harvest of a three-harvest 100-d growing period, regression coefficients for each crop were developed and then used with the model to estimate fresh weights for preceding and succeeding harvests during the same 100-d interval. The model accounted for 72% of the variation in yields in wheatgrass and 94% in yields of alfalfa within the same salinity and water stress treatment period. The model successfully predicted yield in three out of four cases when applied to the first and third harvest yields. Correlations between indices and yield increased as canopy development progressed. Growth reductions attributed to simultaneous salinity and water stress were well characterized, but the

Evaluating high temporal and spatial resolution vegetation index for crop yield prediction

USDA-ARS?s Scientific Manuscript database

Remote sensing data have been widely used in estimating crop yield. Remote sensing derived parameters such as Vegetation Index (VI) were used either directly in building empirical models or by assimilating with crop growth models to predict crop yield. The abilities of remote sensing VI in crop yiel...

Green Chile Pepper Harvest Mechanization

USDA-ARS?s Scientific Manuscript database

Pungent green chile (genus /Capsicum/, also spelled chili) is a large, fragile fruit growing on berry shrubs. Chile is harvested by hand to maximize yields and minimize fruit damage. Labor for hand harvesting chile is increasingly costly and difficult to obtain. Harvest mechanization is viewed as...

Advances in Non-Destructive Early Assessment of Fruit Ripeness towards Defining Optimal Time of Harvest and Yield Prediction—A Review

PubMed Central

Lecourt, Julien; Bishop, Gerard

2018-01-01

Global food security for the increasing world population not only requires increased sustainable production of food but a significant reduction in pre- and post-harvest waste. The timing of when a fruit is harvested is critical for reducing waste along the supply chain and increasing fruit quality for consumers. The early in-field assessment of fruit ripeness and prediction of the harvest date and yield by non-destructive technologies have the potential to revolutionize farming practices and enable the consumer to eat the tastiest and freshest fruit possible. A variety of non-destructive techniques have been applied to estimate the ripeness or maturity but not all of them are applicable for in situ (field or glasshouse) assessment. This review focuses on the non-destructive methods which are promising for, or have already been applied to, the pre-harvest in-field measurements including colorimetry, visible imaging, spectroscopy and spectroscopic imaging. Machine learning and regression models used in assessing ripeness are also discussed. PMID:29320410

Site index, height growth, normal yields and stocking levels for larch in Oregon and Washington.

Treesearch

P.H. Cochran

1985-01-01

Even-aged stands of larch in Oregon and Washington have cubic volume yields similar to yields from larch in Idaho and Montana. Site index values derived from the heights of the single tallest tree on 1/5-acre plots at an age at breast height of 50 years range from 50 to 110 feet. These values have the same index to productivity as the site index values of 30 to 90 feet...

The consequences of balanced harvesting of fish communities

PubMed Central

Jacobsen, Nis S.; Gislason, Henrik; Andersen, Ken H.

2014-01-01

Balanced harvesting, where species or individuals are exploited in accordance with their productivity, has been proposed as a way to minimize the effects of fishing on marine fish communities and ecosystems. This calls for a thorough examination of the consequences balanced harvesting has on fish community structure and yield. We use a size- and trait-based model that resolves individual interactions through competition and predation to compare balanced harvesting with traditional selective harvesting, which protects juvenile fish from fishing. Four different exploitation patterns, generated by combining selective or unselective harvesting with balanced or unbalanced fishing, are compared. We find that unselective balanced fishing, where individuals are exploited in proportion to their productivity, produces a slightly larger total maximum sustainable yield than the other exploitation patterns and, for a given yield, the least change in the relative biomass composition of the fish community. Because fishing reduces competition, predation and cannibalism within the community, the total maximum sustainable yield is achieved at high exploitation rates. The yield from unselective balanced fishing is dominated by small individuals, whereas selective fishing produces a much higher proportion of large individuals in the yield. Although unselective balanced fishing is predicted to produce the highest total maximum sustainable yield and the lowest impact on trophic structure, it is effectively a fishery predominantly targeting small forage fish. PMID:24307676

Examining the roles that changing harvested areas, closing yield-gaps, and increasing yield ceilings have had on crop production

NASA Astrophysics Data System (ADS)

Johnston, M.; Ray, D. K.; Mueller, N. D.; Foley, J. A.

2011-12-01

With an increasing and increasingly affluent population, there has been tremendous effort to examine strategies for sustainably increasing agricultural production to meet this surging global demand. Before developing new solutions from scratch, though, we believe it is important to consult our recent agricultural history to see where and how agricultural production changes have already taken place. By utilizing the newly created temporal M3 cropland datasets, we can for the first time examine gridded agricultural yields and area, both spatially and temporally. This research explores the historical drivers of agricultural production changes, from 1965-2005. The results will be presented spatially at the global-level (5-min resolution), as well as at the individual country-level. The primary research components of this study are presented below, including the general methodology utilized in each phase and preliminary results for soybean where available. The complete assessment will cover maize, wheat, rice, soybean, and sugarcane, and will include country-specific analysis for over 200 countries, states, territories and protectorates. Phase 1: The first component of our research isolates changes in agricultural production due to variation in planting decisions (harvested area) from changes in production due to intensification efforts (yield). We examine area/yield changes at the pixel-level over 5-year time-steps to determine how much each component has contributed to overall changes in production. Our results include both spatial patterns of changes in production, as well as spatial maps illustrating to what degree the production change is attributed to area and/or yield. Together, these maps illustrate where, why, and by how much agricultural production has changed over time. Phase 2: In the second phase of our research we attempt to determine the impact that area and yield changes have had on agricultural production at the country-level. We calculate a production

[Optimum harvest time of Tulipa edulis based on comparison of biomass accumulation and medicinal quality evaluation].

PubMed

Yang, Xiao-Hua; Guo, Qiao-Sheng; Zhu, Zai-Biao; Lin, Jian-Luo; Miao, Yuan-Yuan; Sun, Yuan

2016-02-01

The optimum harvest time of Tulipa edulis was explored based on biomass accumulation and medicinal quality evaluation. Samples were taken from bud stage (Feb 13th) to dormancy stage (May 14th) and the growth indexes, organs biomasses, drying rate, contents of water-soluble extract and polysaccharides were determined. The results showed that biomass distribution of T. edulis varied with growth center and the bulb gained maximum biomass allocation in the whole growth period. The total biomass accumulation and bulb biomass accumulation　increased in the whole growth period and peaked in fructescence stage. No differences were observed in bulb biomass among fructescence stage, withering stage and dormancy stage. The correlation between bulb biomass allocation and other morphological indexes varied with the harvest time. Bulb dry weight biomass had negative correlation with some morphological indexes of aerial part of T. edulis at bud stage, flower stage and fructescence and had significant positive (P<0.05) or extremely significant positive correlation（P<0.01）with other morphological indexes except for root at bearing fruits stage. The drying rate of bulb of T. edulis increased with the extension of harvest time and peaked in dormancy stage. The water-soluble extract of T. edulis bulb was the highest in pre-growing-stage. The tendency of polysaccharides contents showed a W-shape variation during the harvesting period. The polysaccharides content was the lowest in fructescence stage and was the highest in dormancy stage. Considering the yield and medicinal quality of T. edulis bulb, the optimum harvest time of T. edulis is in the withering stage or early stage of dormancy. Copyright© by the Chinese Pharmaceutical Association.

Harvest index, a parameter conditioning responsiveness of wheat plants to elevated CO2

PubMed Central

Aranjuelo, Iker; Sanz-Sáez, Álvaro; Jauregui, Iván; Irigoyen, Juan J.; Araus, José L.; Sánchez-Díaz, Manuel; Erice, Gorka

2013-01-01

The expansion of the world’s population requires the development of high production agriculture. For this purpose, it is essential to identify target points conditioning crop responsiveness to predicted [CO2]. The aim of this study was to determine the relevance of ear sink strength in leaf protein and metabolomic profiles and its implications in photosynthetic activity and yield of durum wheat plants exposed to elevated [CO2]. For this purpose, a genotype with high harvest index (HI) (Triticum durum var. Sula) and another with low HI (Triticum durum var. Blanqueta) were exposed to elevated [CO2] (700 µmol mol–1 versus 400 µmol mol–1 CO2) in CO2 greenhouses. The obtained data highlighted that elevated [CO2] only increased plant growth in the genotype with the largest HI; Sula. Gas exchange analyses revealed that although exposure to 700 µmol mol–1 depleted Rubisco content, Sula was capable of increasing the light-saturated rate of CO2 assimilation (Asat) whereas, in Blanqueta, the carbohydrate imbalance induced the down-regulation of Asat. The specific depletion of Rubisco in both genotypes under elevated [CO2], together with the enhancement of other proteins in the Calvin cycle, revealed that there was a redistribution of N from Rubisco towards RuBP regeneration. Moreover, the down-regulation of N, NO3 –, amino acid, and organic acid content, together with the depletion of proteins involved in amino acid synthesis that was detected in Blanqueta grown at 700 µmol mol–1 CO2, revealed that inhibition of N assimilation was involved in the carbohydrate imbalance and consequently with the down-regulation of photosynthesis and growth in these plants. PMID:23564953

Piezoelectric energy harvester under parquet floor

NASA Astrophysics Data System (ADS)

Bischur, E.; Schwesinger, N.

2011-03-01

The design, fabrication and testing of piezoelectric energy harvesting modules for floors is described. These modules are used beneath a parquet floor to harvest the energy of people walking over it. The harvesting modules consist of monoaxial stretched PVDF-foils. Multilayer modules are built up as roller-type capacitors. The fabrication process of the harvesting modules is simple and very suitable for mass production. Due to the use of organic polymers, the modules are characterized by a great flexibility and the possibility to create them in almost any geometrical size. The energy yield was determined depending on the dynamic loading force, the thickness of piezoelectric active material, the size of the piezoelectric modules, their alignment in the walking direction and their position on the floor. An increase of the energy yield at higher loading forces and higher thicknesses of the modules was observed. It was possible to generate up to 2.1mWs of electric energy with dynamic loads of 70kg using a specific module design. Furthermore a test floor was assembled to determine the influence of the size, alignment and position of the modules on the energy yield.

Increased Night Temperature Negatively Affects Grain Yield, Biomass and Grain Number in Chilean Quinoa

PubMed Central

Lesjak, Jurka; Calderini, Daniel F.

2017-01-01

Quinoa high nutritive value increases interest worldwide, especially as a crop that could potentially feature in different cropping systems, however, climate change, particularly rising temperatures, challenges this and other crop species. Currently, only limited knowledge exists regarding the grain yield and other key traits response to higher temperatures of this crop, especially to increased night temperatures. In this context, the main objective of this study was to evaluate the effect of increased night temperature on quinoa yield, grain number, individual grain weight and processes involved in crop growth under the environmental conditions (control treatment) and night thermal increase at two phases: flowering (T1) and grain filling (T2) in southern Chile. A commercial genotype, Regalona, and a quinoa accession (Cod. BO5, N°191, grain bank from Semillas Baer, hereby referred to as Accession) were used, due to their adaptability to Southern Chilean conditions and contrasting grain yield potential, grain weight and size of plants. Temperature was increased ≈4°C above the ambient from 8 pm until 9 am the next morning. Control treatments reached a high grain yield (600 and 397 g m-2, i.e., Regalona and Accession). Temperature increase reduced grain yield by 31% under T1 treatment and 12% when under T2 in Regalona and 23 and 26% in Accession, respectively. Aboveground biomass was negatively affected by the thermal treatments and a positive linear association was found between grain yield and aboveground biomass across treatments. By contrast, the harvest index was unaffected either by genotype, or by thermal treatments. Grain number was significantly affected between treatments and this key trait was linearly associated with grain yield. On the other hand, grain weight showed a narrow range of variation across treatments. Additionally, leaf area index was not affected, but significant differences were found in SPAD values at the end of T1 treatment, compared

High temperature stress and its effect on pollen development and morphological components of harvest index in the C3 model grass Brachypodium distachyon

PubMed Central

Harsant, Jeffrey; Pavlovic, Lazar; Chiu, Greta; Sultmanis, Stefanie; Sage, Tammy L.

2013-01-01

The effect of high temperatures on harvest index (HI) and morphological components that contribute to HI was investigated in two lines (Bd21 and Bd21-3) of Brachypodium distachyon, a C3 grass recognized as a tractable plant, to address critical issues associated with enhancing cereal crop yields in the presence of global climate change. The results demonstrated that temperatures ≥32 °C eliminated HI. Reductions in yield at 32 °C were due primarily to declines in pollen viability, retention of pollen in anthers, and pollen germination, while abortion of microspores by the uninucleate stage that was correlated with abnormal tapetal development resulted in yield failure at 36 °C. Increasing temperatures from 24 to 32 °C resulted in reductions in tiller numbers but had no impact on axillary branch numbers per tiller. Grain developed at 24 and 28 °C primarily in tiller spikes, although spikes on axillary branches also formed grain. Grain quantity decreased in tiller spikes but increased in axillary branch spikes as temperatures rose from 24 to 28 °C. Differential patterns of axillary branching and floret development within spikelets between Bd21 and Bd21-3 resulted in higher grain yield in axillary branches of Bd21-3 at 28 °C. The response of male reproductive development and tiller branching patterns in B. distachyon to increasing temperatures mirrors that in other cereal crops, providing support for the use of this C3 grass in assessing the molecular control of HI in the presence of global warming. PMID:23771979

Light harvesting control in plants.

PubMed

Ruban, Alexander V

2018-05-23

In 1991, my colleagues and I published a hypothesis article that proposed a mechanism that controls light harvesting in plants and protects them against photodamage. The major light harvesting complex, LHCII, was suggested to undergo aggregation upon exposure of the plant to damaging levels of light. Aggregated LHCII was found to be much less efficient in light harvesting, as it promptly dissipated absorbed energy into heat, possessing a very low chlorophyll fluorescence yield. Non-photochemical quenching (NPQ) is a term coined to describe this reduction in chlorophyll fluorescence yield. This article is a story of how the hypothesis that LHCII aggregation is involved in NPQ is developed into a model that is now becoming broadly accepted by the research community. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Effect of crop residue harvest on long-term crop yield, soil erosion, and carbon balance: tradeoffs for a sustainable bioenergy feedstock

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gregg, Jay S.; Izaurralde, Roberto C.

2010-08-26

Agricultural residues are a potential feedstock for bioenergy production, if residue harvest can be done sustainably. The relationship between crop residue harvest, soil erosion, crop yield and carbon balance was modeled with the Erosion Productivity Impact Calculator/ Environment Policy Integrated Climate (EPIC) using a factorial design. Four crop rotations (winter wheat [Triticum aestivum (L.)] – sunflower [Helianthus annuus]; spring wheat [Triticum aestivum (L.)] – canola [Brassica napus]; corn [Zea mays L.] – soybean [Glycine max (L.) Merr.]; and cotton [Gossypium hirsutum] – peanut [Arachis hypogaea]) were simulated at four US locations each, under different topographies (0-10% slope), and management practicesmore » [crop residue removal rates (0-75%), conservation practices (no till, contour cropping, strip cropping, terracing)].« less

Effective Use of Water and Increased Dry Matter Partitioned to Grain Contribute to Yield of Common Bean Improved for Drought Resistance

PubMed Central

Polania, Jose A.; Poschenrieder, Charlotte; Beebe, Stephen; Rao, Idupulapati M.

2016-01-01

Common bean (Phaseolus vulgaris L.) is the most important food legume in the diet of poor people in the tropics. Drought causes severe yield loss in this crop. Identification of traits associated with drought resistance contributes to improving the process of generating bean genotypes adapted to these conditions. Field studies were conducted at the International Center for Tropical Agriculture (CIAT), Palmira, Colombia, to determine the relationship between grain yield and different parameters such as effective use of water (EUW), canopy biomass, and dry partitioning indices (pod partitioning index, harvest index, and pod harvest index) in elite lines selected for drought resistance over the past decade. Carbon isotope discrimination (CID) was used for estimation of water use efficiency (WUE). The main objectives were: (i) to identify specific morpho-physiological traits that contribute to improved resistance to drought in lines developed over several cycles of breeding and that could be useful as selection criteria in breeding; and (ii) to identify genotypes with desirable traits that could serve as parents in the corresponding breeding programs. A set of 36 bean genotypes belonging to the Middle American gene pool were evaluated under field conditions with two levels of water supply (irrigated and drought) over two seasons. Eight bean lines (NCB 280, NCB 226, SEN 56, SCR 2, SCR 16, SMC 141, RCB 593, and BFS 67) were identified as resistant to drought stress. Resistance to terminal drought stress was positively associated with EUW combined with increased dry matter partitioned to pod and seed production and negatively associated with days to flowering and days to physiological maturity. Differences in genotypic response were observed between grain CID and grain yield under irrigated and drought stress. Based on phenotypic differences in CID, leaf stomatal conductance, canopy biomass, and grain yield under drought stress, the lines tested were classified into two

Assessment of atmospheric moisture harvesting by direct cooling

NASA Astrophysics Data System (ADS)

Gido, Ben; Friedler, Eran; Broday, David M.

2016-12-01

The enormous amount of water vapor present in the atmosphere may serve as a potential water resource. An index is proposed for assessing the feasibility and energy requirements of atmospheric moisture harvesting by a direct cooling process. A climate-based analysis of different locations reveals the global potential of this process. We demonstrate that the Moisture Harvesting Index (MHI) can be used for assessing the energy requirements of atmospheric moisture harvesting. The efficiency of atmospheric moisture harvesting is highly weather and climate dependent, with the smallest estimated energy requirement found at the tropical regions of the Philippines (0.23 kW/L). Less favorable locations have much higher energy demands for the operation of an atmospheric moisture harvesting device. In such locations, using the MHI to select the optimal operation time periods (during the day and the year) can reduce the specific energy requirements of the process dramatically. Still, using current technology the energy requirement of atmospheric moisture harvesting by a direct air cooling process is significantly higher than of desalination by reverse osmosis.

Spatial and Temporal Uncertainty of Crop Yield Aggregations

NASA Technical Reports Server (NTRS)

Porwollik, Vera; Mueller, Christoph; Elliott, Joshua; Chryssanthacopoulos, James; Iizumi, Toshichika; Ray, Deepak K.; Ruane, Alex C.; Arneth, Almut; Balkovic, Juraj; Ciais, Philippe;

Effect of lamp type and temperature on development, carbon partitioning and yield of soybean

NASA Astrophysics Data System (ADS)

Dougher, T. A. O.; Bugbee, B.

1997-01-01

Soybeans grown in controlled environments are commonly taller than field-grown plants. In controlled environments, including liquid hydroponics, height of the dwarf cultivar ``Hoyt'' was reduced from 46 to 33 cm when plants were grown under metal halide lamps compared to high pressure sodium lamps at the same photosynthetic photon flux. Metal halide lamps reduced total biomass 14% but did not significantly reduce seed yield. Neither increasing temperature nor altering the difference between day/night temperature affected plant height. Increasing temperature from 21 to 27 degC increased yield 32%. High temperature significantly increased carbon partitioning to stems and increased harvest index.

Modelling climate change impacts on viticultural yield, phenology and stress conditions in Europe.

PubMed

Fraga, Helder; García de Cortázar Atauri, Iñaki; Malheiro, Aureliano C; Santos, João A

2016-11-01

Viticulture is a key socio-economic sector in Europe. Owing to the strong sensitivity of grapevines to atmospheric factors, climate change may represent an important challenge for this sector. This study analyses viticultural suitability, yield, phenology, and water and nitrogen stress indices in Europe, for present climates (1980-2005) and future (2041-2070) climate change scenarios (RCP4.5 and 8.5). The STICS crop model is coupled with climate, soil and terrain databases, also taking into account CO 2 physiological effects, and simulations are validated against observational data sets. A clear agreement between simulated and observed phenology, leaf area index, yield and water and nitrogen stress indices, including the spatial differences throughout Europe, is shown. The projected changes highlight an extension of the climatic suitability for grapevines up to 55°N, which may represent the emergence of new winemaking regions. Despite strong regional heterogeneity, mean phenological timings (budburst, flowering, veraison and harvest) are projected to undergo significant advancements (e.g. budburst/harvest can be >1 month earlier), with implications also in the corresponding phenophase intervals. Enhanced dryness throughout Europe is also projected, with severe water stress over several regions in southern regions (e.g. southern Iberia and Italy), locally reducing yield and leaf area. Increased atmospheric CO 2 partially offsets dryness effects, promoting yield and leaf area index increases in central/northern Europe. Future biomass changes may lead to modifications in nitrogen demands, with higher stress in northern/central Europe and weaker stress in southern Europe. These findings are critical decision support systems for stakeholders from the European winemaking sector. © 2016 John Wiley & Sons Ltd.

Rice yield in response to climate trends and drought index in the Mun River Basin, Thailand.

PubMed

Prabnakorn, Saowanit; Maskey, Shreedhar; Suryadi, F X; de Fraiture, Charlotte

2018-04-15

Rice yields in Thailand are among the lowest in Asia. In northeast Thailand where about 90% of rice cultivation is rain-fed, climate variability and change affect rice yields. Understanding climate characteristics and their impacts on the rice yield is important for establishing proper adaptation and mitigation measures to enhance productivity. In this paper, we investigate climatic conditions of the past 30years (1984-2013) and assess the impacts of the recent climate trends on rice yields in the Mun River Basin in northeast Thailand. We also analyze the relationship between rice yield and a drought indicator (Standardized Precipitation and Evapotranspiration Index, SPEI), and the impact of SPEI trends on the yield. Our results indicate that the total yield losses due to past climate trends are rather low, in the range of <50kg/ha per decade (3% of actual average yields). In general, increasing trends in minimum and maximum temperatures lead to modest yield losses. In contrast, precipitation and SPEI-1, i.e. SPEI based on one monthly data, show positive correlations with yields in all months, except in the wettest month (September). If increasing trends of temperatures during the growing season persist, a likely climate change scenario, there is high possibility that the yield losses will become more serious in future. In this paper, we show that the drought index SPEI-1 detects soil moisture deficiency and crop stress in rice better than precipitation or precipitation based indicators. Further, our results emphasize the importance of spatial and temporal resolutions in detecting climate trends and impacts on yields. Copyright © 2017 Elsevier B.V. All rights reserved.

Estimating and validating harvesting system production through computer simulation

Treesearch

John E. Baumgras; Curt C. Hassler; Chris B. LeDoux

1993-01-01

A Ground Based Harvesting System Simulation model (GB-SIM) has been developed to estimate stump-to-truck production rates and multiproduct yields for conventional ground-based timber harvesting systems in Appalachian hardwood stands. Simulation results reflect inputs that define harvest site and timber stand attributes, wood utilization options, and key attributes of...

2011 High Plains and Northern Rolling Plains Cotton Harvest-Aid Guide

USDA-ARS?s Scientific Manuscript database

Harvest-aid chemicals are generally applied to hasten harvest of a mature crop and to reduce potential preharvest losses of lint yield and fiber quality. Proper use of harvest aids can result in earlier harvest, preservation of fiber quality, and fewer seed quality reductions due to field exposure. ...

2009 High plains and northern rolling plains cotton harvest-aid guide

USDA-ARS?s Scientific Manuscript database

Harvest-aid chemicals are generally applied to hasten harvest of a mature crop, and to reduce potential preharvest losses of lint yield and fiber quality. Proper use of harvest aids can result in earlier harvest, preservation of fiber quality, and fewer seed quality reductions due to field exposure....

2012 High Plains and Northern Rolling Plains Cotton harvest aid-guide

USDA-ARS?s Scientific Manuscript database

Harvest-aid chemicals are generally applied to hasten harvest of a mature crop, and to reduce potential preharvest losses of lint yield and fiber quality. Proper use of harvest aids can result in earlier harvest, preservation of fiber quality, and fewer seed quality reductions due to field exposure....

Development of growth and yield models for southern hardwoods: site index determinations

Treesearch

John Paul McTague; Daniel J. Robison; David O' Loughlin; Joseph Roise; Robert Kellison

2006-01-01

Growth and yield data from across 13 southern States, collected from 1967 to 2004 from fully-stocked even-aged southern hardwood forests on a variety of site types, was used to calculate site index curves. These derived curves provide an efficient means to evaluate the productivity-age relation which varies across many sites. These curves were derived for mixed-species...

A Novel Approach for Forecasting Crop Production and Yield Using Remotely Sensed Satellite Images

NASA Astrophysics Data System (ADS)

Singh, R. K.; Budde, M. E.; Senay, G. B.; Rowland, J.

2017-12-01

Forecasting crop production in advance of crop harvest plays a significant role in drought impact management, improved food security, stabilizing food grain market prices, and poverty reduction. This becomes essential, particularly in Sub-Saharan Africa, where agriculture is a critical source of livelihoods, but lacks good quality agricultural statistical data. With increasing availability of low cost satellite data, faster computing power, and development of modeling algorithms, remotely sensed images are becoming a common source for deriving information for agricultural, drought, and water management. Many researchers have shown that the Normalized Difference Vegetation Index (NDVI), based on red and near-infrared reflectance, can be effectively used for estimating crop production and yield. Similarly, crop production and yield have been closely related to evapotranspiration (ET) also as there are strong linkages between production/yield and transpiration based on plant physiology. Thus, we combined NDVI and ET information from remotely sensed images for estimating total production and crop yield prior to crop harvest for Niger and Burkina Faso in West Africa. We identified the optimum time (dekads 23-29) for cumulating NDVI and ET and developed a new algorithm for estimating crop production and yield. We used the crop data from 2003 to 2008 to calibrate our model and the data from 2009 to 2013 for validation. Our results showed that total crop production can be estimated within 5% of actual production (R2 = 0.98) about 30-45 days before end of the harvest season. This novel approach can be operationalized to provide a valuable tool to decision makers for better drought impact management in drought-prone regions of the world.

Computing wheat nitrogen requirements from grain yield and protein maps

USDA-ARS?s Scientific Manuscript database

Optical protein sensors and mass-flow yield monitors provide the opportunity to continuously measure grain quality and quantity during harvesting. This chapter illustrates how yield monitor and grain protein measurements may provide useful post-harvest information for evaluating water or nitrogen (...

Improving adaptation to drought stress in white pea bean (Phaseolus vulgaris L): genotypic effects on grain yield, yield components and pod harvest index

USDA-ARS?s Scientific Manuscript database

Common bean (Phaseolus vulgaris L.) is the most important food legume crop in Africa and Latin America where rainfall pattern is unpredictable. The objectives were to identify better yielding common bean lines with good canning quality under drought, and to identify traits that could be used as sele...

[Effects of flower bud removal and artificial pollination on growth and yield of Tulipa edulis].

PubMed

Miao, Yuan-Yuan; Zhu, Zai-Biao; Guo, Qiao-Sheng; Ma, Hong-Liang; Yang, Ying; Zhu, Li-Fang

2014-06-01

The study was conducted to explore the response of growth and yield of Tulipa edulis to flower bud removal and artificial pollination. And flower bud removal and artificial pollination were carried out in the squaring period and bloom stage respectively. The morphological index and biomass indicators were determined and the yield was counted in harvest time. Result showed that flower bud removal was beneficial to the growth of T. edulis, resulting in increasing growth index, biomass as well as the yield of bulb. The diameter and dry weight of T. edulis fruit by artificial pollination were increased significantly compared with the control. Seed setting percentage increased to 100%, and the number of seed as well as the single grain weight increased by 69.03% and 16.48%, respectively, which did not significantly affect the bulb production. In conclusion, Flower bud removal treatment accelerates bulb biomass increase, so as to improve its yield. Artificial pollination raised significantly seed setting percentage, seed number as well as the single grain weight.

Prediction of County-Level Corn Yields Using an Energy-Crop Growth Index.

NASA Astrophysics Data System (ADS)

Andresen, Jeffrey A.; Dale, Robert F.; Fletcher, Jerald J.; Preckel, Paul V.

1989-01-01

Weather conditions significantly affect corn yields. while weather remains as the major uncontrolled variable in crop production, an understanding of the influence of weather on yields can aid in early and accurate assessment of the impact of weather and climate on crop yields and allow for timely agricultural extension advisories to help reduce farm management costs and improve marketing, decisions. Based on data for four representative countries in Indiana from 1960 to 1984 (excluding 1970 because of the disastrous southern corn leaf blight), a model was developed to estimate corn (Zea mays L.) yields as a function of several composite soil-crop-weather variables and a technology-trend marker, applied nitrogen fertilizer (N). The model was tested by predicting corn yields for 15 other counties. A daily energy-crop growth (ECG) variable in which different weights were used for the three crop-weather variables which make up the daily ECG-solar radiation intercepted by the canopy, a temperature function, and the ratio of actual to potential evapotranspiration-performed better than when the ECG components were weighted equally. The summation of the weighted daily ECG over a relatively short period (36 days spanning silk) was found to provide the best index for predicting county average corn yield. Numerical estimation results indicate that the ratio of actual to potential evapotranspiration (ET/PET) is much more important than the other two ECG factors in estimating county average corn yield in Indiana.

Optimizing nitrogen application rate and plant density for improving cotton yield and nitrogen use efficiency in the North China Plain

PubMed Central

Dong, Helin; Zheng, Cangsong; Sun, Miao; Liu, Aizhong; Wang, Guoping; Liu, Shaodong; Zhang, Siping; Chen, Jing; Li, Yabing; Pang, Chaoyou; Zhao, Xinhua

2017-01-01

Plant population density (PPD) and nitrogen (N) application rate (NAR) are two controllable factors in cotton production. We conducted field experiments to investigate the effects of PPD, NAR and their interaction (PPD × NAR) on yield, N uptake and N use efficiency (NUE) of cotton using a split-plot design in the North China Plain during 2013 and 2014. The main plots were PPDs (plants m−2) of 3.00 (low), 5.25 (medium) and 7.50 (high) and the subplots were NARs of 0 (N-free), 112.5 (low), 225.0 (moderate) and 337.5 (high). During both 2013 and 2014, biological yield and N uptake of cotton increased significantly, but harvesting index decreased significantly with NAR and PPD increasing. With NAR increasing, internal nitrogen use efficiency(NUE) decreased significantly under three PPDs and agronomical NUE, physiologilal NUE, nitrogen recovery efficiency(NRE) and partial factor productivity from applied nitrogen (PFPN) also decreased significantly under high PPD between two years. Lint yield increment varied during different PPDs and years, but NAR enhancement showed less function under higher PPD than lower PPD in general. Taken together, moderate NAR under medium PPD combined higher lint yield with higher agronomic NUE, physiological NUE, and NRE, while low NAR with high PPD would achieve a comparable yield with superior NRE and PFPN and high NAR under high PPD and medium PPD produced higher biological yield but lower harvest index, lint yield and NUE compared to moderate NAR with medium PPD. Our overall results indicated that, in this region, increasing PPD and decreasing NAR properly would enhance both lint yield and NUE of cotton. PMID:28981538

Estimating sugarcane yield potential using an in-season determination of normalized difference vegetative index.

PubMed

Lofton, Josh; Tubana, Brenda S; Kanke, Yumiko; Teboh, Jasper; Viator, Howard; Dalen, Marilyn

2012-01-01

Estimating crop yield using remote sensing techniques has proven to be successful. However, sugarcane possesses unique characteristics; such as, a multi-year cropping cycle and plant height-limiting for midseason fertilizer application timing. Our study objective was to determine if sugarcane yield potential could be estimated using an in-season estimation of normalized difference vegetative index (NDVI). Sensor readings were taken using the GreenSeeker® handheld sensor from 2008 to 2011 in St. Gabriel and Jeanerette, LA, USA. In-season estimates of yield (INSEY) values were calculated by dividing NDVI by thermal variables. Optimum timing for estimating sugarcane yield was between 601-750 GDD. In-season estimated yield values improved the yield potential (YP) model compared to using NDVI. Generally, INSEY value showed a positive exponential relationship with yield (r(2) values 0.48 and 0.42 for cane tonnage and sugar yield, respectively). When models were separated based on canopy structure there was an increase the strength of the relationship for the erectophile varieties (r(2) 0.53 and 0.47 for cane tonnage and sugar yield, respectively); however, the model for planophile varieties weakened slightly. Results of this study indicate using an INSEY value for predicting sugarcane yield shows potential of being a valuable management tool for sugarcane producers in Louisiana.

Insights from Placing Photosynthetic Light Harvesting into Context.

PubMed

Demmig-Adams, Barbara; Stewart, Jared J; Burch, Tyson A; Adams, William W

2014-08-21

Solar-energy conversion through natural photosynthesis forms the base of virtually all food chains on Earth and provides fiber, materials, and fuels, as well as inspiration for the design of biomimetic energy-conversion systems. We summarize well-known as well as recently discovered feedback loops between natural light-harvesting systems and whole-organism function in natural settings. We propose that the low effective quantum yield of natural light-harvesting systems in high light is caused by downstream limitations rather than unavoidable intrinsic vulnerabilities. We evaluate potential avenues, and their costs and benefits, for increasing the maximal rate and photon yield of photosynthesis in high light in plants and photosynthetic microbes. By summarizing mechanisms observable only in complex systems (whole plants, algae, or, in some cases, intact leaves), we aim to stimulate future research efforts on reciprocal feedback loops between light harvesting and downstream processes in whole organisms and to provide additional arguments for the significance of research on photosynthetic light harvesting.

Harvesting and replenishment policies for renewable natural resources

USGS Publications Warehouse

Douglas, Aaron J.; Johnson, Richard L.

1993-01-01

The current paper links the optimal intertemporal use of renewable natural resources to the harvesting activities of various economic agents. Previous contributions cite market forces as a causative factor inducing the extirpation of renewable natural resources. The analysis given here discusses investment in the stock of renewable resources and cites important examples of this activity. By introducing joint harvesting and replenishment strategies into a model of renewable resource use, the analysis adds descriptive reality and relevance to positive and normative discussions of renewable natural resource use. A high price for the yield or a high discount rate tend to diminish the size of the optimum stationary stock of the resource with a non-replenishment harvesting strategy. Optimal non-replenishment harvesting strategies for renewable natural resources will exhaustion or extirpation of the resource if the price of the yield or the discount rate are sufficiently large. However, the availability of a replenishment technology and the use of replenishment activities tends to buffer the resource against exhaustion or extirpation.

West Virginia harvest and utilization study, 2008

Treesearch

Jan Wiedenbeck; Shawn Grushecky

2014-01-01

Thirty active harvesting operations were part of a harvest and utilization study conducted in West Virginia in 2008. Data were collected on roundwood product and residue yields obtained from trees of different sizes, species, and qualities. This study was modeled after studies conducted on a regular and frequent basis by the Forest Inventory and Analysis unit in the...

Energy harvesting from sea waves with consideration of airy and JONSWAP theory and optimization of energy harvester parameters

NASA Astrophysics Data System (ADS)

Mirab, Hadi; Fathi, Reza; Jahangiri, Vahid; Ettefagh, Mir Mohammad; Hassannejad, Reza

2015-12-01

One of the new methods for powering low-power electronic devices at sea is a wave energy harvesting system. In this method, piezoelectric material is employed to convert the mechanical energy of sea waves into electrical energy. The advantage of this method is based on avoiding a battery charging system. Studies have been done on energy harvesting from sea waves, however, considering energy harvesting with random JONSWAP wave theory, then determining the optimum values of energy harvested is new. This paper does that by implementing the JONSWAP wave model, calculating produced power, and realistically showing that output power is decreased in comparison with the more simple airy wave model. In addition, parameters of the energy harvester system are optimized using a simulated annealing algorithm, yielding increased produced power.

[Comparison of different harvest ways of Dendrobium officinale].

PubMed

Wang, Yang; Zhu, Yan; Si, Jin-Ping; Liu, Jing-Jing; Zhu, Yu-Qiu; Liu, Xiu-Juan

2015-03-01

To standardize the harvest ways of Dendrobium officinale and improve the quality and yield of D. officinale, a field experiment was carried out to study the effect of two kinds of harvest ways, which were keeping some of the axial shoot and harvesting all of the shoot by the end of the year. Then, the agronomic traits and yield were measured and the contents of polysaccharides and extractum were determined. The results showed that the harvest ways significantly affected the growth of D. officinale. Keeping some of the axial shoot could significantly improved the number of sprout, stem length, internode number and the internodal length, which also triggered increase the weight of fresh stems, leaves and the total of them and dry stems in per unit area, but it could not promote the stem diameter and the polysaccharide content in stems. Keeping some of the axial shoot moderately was conducive to the improvement of the production of medicinal materials in the process of harvesting by promoting the germination and growth of new buds, and to ensure the polysaccharide content by regulating the illumination and the density of cultivation.

Contribution of morphoagronomic traits to grain yield and earliness in grain sorghum.

PubMed

da Silva, K J; Teodoro, P E; de Menezes, C B; Júlio, M P M; de Souza, V F; da Silva, M J; Pimentel, L D; Borém, A

2017-05-04

Given the importance of selecting lines to obtain hybrids, we aimed to verify the relationship between morphological traits that can be used as the criteria for the selection of sorghum lines with high grain yield and earliness. A total of 18 traits were evaluated in 160 sorghum elite lines, in an incomplete block design with two replicates. A correlation network was used to graphically express the estimates of phenotypic and genotypic correlations between the traits. Two path analyses were processed, the first considering grain yield and the second considering flowering as the principle dependent variable. In general, most of the variation in the grain yield and flowering of sorghum lines was explained by the traits evaluated. Selecting sorghum lines with greater width of the third leaf blade from flag leaf, panicle weight, and panicle harvest index might lead to increased grain yield, and selecting sorghum genotypes with higher plant height might lead to reduced earliness and increased grain yield. Thus, the results suggest the establishment of selection indices aiming at simultaneously increasing the grain yield and earliness in sorghum genotypes.

Use of Drought Index and Crop Modelling for Drought Impacts Analysis on Maize (Zea mays L.) Yield Loss in Bandung District

NASA Astrophysics Data System (ADS)

Kurniasih, E.; Impron; Perdinan

2017-03-01

Drought impacts on crop yield loss depend on drought magnitude and duration and on plant genotype at every plant growth stages when droughts occur. This research aims to assess the difference calculation results of 2 drought index methods and to study the maize yield loss variability impacted by drought magnitude and duration during maize growth stages in Bandung district, province of West Java, Indonesia. Droughts were quantified by the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI) at 1- to 3-month lags for the January1986-December 2015 period data. Maize yield responses to droughts were simulated by AquaCrop for the January 1986-May 2016 period of growing season. The analysis showed that the SPI and SPEI methods provided similar results in quantifying drought event. Droughts during maize reproductive stages caused the highest maize yield loss.

Assessment of the performance of water harvesting systems in semi-arid regions

NASA Astrophysics Data System (ADS)

Lasage, Ralph

2016-04-01

Water harvesting is widely practiced and has the potential to improve water availability for domestic and agricultural use in semi-arid regions. New funds are becoming available to stimulate the implementation of water harvesting projects, for meeting the Sustainable Development Goals and to help communities to adapt to climate change. For this, it is important to understand which factors determine the success of water harvesting techniques under different conditions. For this, we review the literature, including information on the crop yield impacts of water harvesting projects in semi-arid Africa and Asia. Results show that large water harvesting structures (> 500 m3) are less expensive than small structures, when taking into account investment costs, storage capacity and lifetimes. We also find that water harvesting improves crop yields significantly, and that the relative impact of water harvesting on crop yields is largest in low rainfall years. We also see that the governance, technical knowledge and initial investment are more demanding for the larger structures than for smaller structures, which may affect their spontaneous adoption and long term sustainability when managed by local communities. To support the selection of appropriate techniques, we present a decision framework based on case specific characteristics. This framework can also be used when reporting and evaluating the performance of water harvesting techniques, which is up to now quite limited in peer reviewed literature. Based on Bouma, J., Hegde, S.E., Lasage, R., (2016). Assessing the returns to water harvesting: A meta-analysis. Agricultural Water Management 163, 100-109. Lasage, R., Verburg P.H., (2015). Evaluation of small scale water harvesting techniques for semi-arid environments. Journal of Arid Environments 118, 48-57.

Flexible Piezoelectric Energy Harvesting from Mouse Click Motions

PubMed Central

Cha, Youngsu; Hong, Jin; Lee, Jaemin; Park, Jung-Min; Kim, Keehoon

2016-01-01

In this paper, we study energy harvesting from the mouse click motions of a robot finger and a human index finger using a piezoelectric material. The feasibility of energy harvesting from mouse click motions is experimentally and theoretically assessed. The fingers wear a glove with a pocket for including the piezoelectric material. We model the energy harvesting system through the inverse kinematic framework of parallel joints in a finger and the electromechanical coupling equations of the piezoelectric material. The model is validated through energy harvesting experiments in the robot and human fingers with the systematically varying load resistance. We find that energy harvesting is maximized at the matched load resistance to the impedance of the piezoelectric material, and the harvested energy level is tens of nJ. PMID:27399705

Remotely sensed vegetation indices for seasonal crop yields predictions in the Czech Republic

NASA Astrophysics Data System (ADS)

Hlavinka, Petr; Semerádová, Daniela; Balek, Jan; Bohovic, Roman; Žalud, Zdeněk; Trnka, Miroslav

2015-04-01

Remotely sensed vegetation indices by satellites are valuable tool for vegetation conditions assessment also in the case of field crops. This study is based on the use of NDVI (Normalized Difference Vegetation Index) and EVI (Enhanced Vegetation Index) derived from MODIS (Moderate Resolution Imaging Spectroradiometer) aboard Terra satellite. Data available from the year 2000 were analyzed and tested for seasonal yields predictions within selected districts of the Czech Republic (Central Europe). Namely the yields of spring barley, winter wheat and oilseed winter rape during the period from 2000 to 2014 were assessed. Observed yields from 14 districts (NUTS 4) were collected and thus 210 seasons were included. Selected districts differ considerably in their soil fertility and terrain configuration and represent transect across various agroclimatic conditions (from warm and dry to relative cool and wet regions). Two approaches were tested: 1) using of composite remotely sensed data (available in 16 day time step) provided by the USGS (https://lpdaac.usgs.gov/); 2) using daily remotely sensed data in combination with originally developed smoothing method. The yields were successfully predicted based on established regression models (remotely sensed data used as independent parameter). Besides others the impact of severe drought episodes within vegetation were identified and yield reductions at district level predicted (even before harvest). As a result the periods with the best relationship between remotely sensed data and yields were identified. The impact of drought conditions as well as normal or above normal yields of field crops could be predicted by proposed method within study region up to 30 days prior to the harvest. It could be concluded that remotely sensed vegetation conditions assessment should be important part of early warning systems focused on drought. Such information should be widely available for various users (decision makers, farmers, etc.) in

Pistil Smut Infection Increases Ovary Production, Seed Yield Components, and Pseudosexual Reproductive Allocation in Buffalograss

PubMed Central

Chandra, Ambika; Huff, David R.

2014-01-01

Sex expression of dioecious buffalograss [Bouteloua dactyloides Columbus (syn. Buchloë dactyloides (Nutt.) Engelm.)] is known to be environmentally stable with approximate 1:1, male to female, sex ratios. Here we show that infection by the pistil smut fungus [Salmacisia buchloëana Huff & Chandra (syn. Tilletia buchloëana Kellerman and Swingle)] shifts sex ratios of buffalograss to be nearly 100% phenotypically hermaphroditic. In addition, pistil smut infection decreased vegetative reproductive allocation, increased most seed yield components, and increased pseudosexual reproductive allocation in both sex forms compared to uninfected clones. In female sex forms, pistil smut infection resulted in a 26 fold increase in ovary production and a 35 fold increase in potential harvest index. In male sex forms, pistil smut infection resulted in 2.37 fold increase in floret number and over 95% of these florets contained a well-developed pistil. Although all ovaries of infected plants are filled with fungal teliospores and hence reproductively sterile, an average male-female pair of infected plants exhibited an 87 fold increase in potential harvest index compared to their uninfected clones. Acquiring an ability to mimic the effects of pistil smut infection would enhance our understanding of the flowering process in grasses and our efforts to increase seed yield of buffalograss and perhaps other grasses. PMID:27135522

Performance of Vegetation Indices for Wheat Yield Forecasting for Punjab, Pakistan

NASA Astrophysics Data System (ADS)

Dempewolf, J.; Becker-Reshef, I.; Adusei, B.; Barker, B.

2013-12-01

Forecasting wheat yield in major producer countries early in the growing season allows better planning for harvest deficits and surplus with implications for food security, world market transactions, sustaining adequate grain stocks, policy making and other matters. Remote sensing imagery is well suited for yield forecasting over large areas. The Normalized Difference Vegetation Index (NDVI) has been the most-used spectral index derived from remote sensing imagery for assessing crop condition of major crops and forecasting crop yield. Many authors have found that the highest correlation between NDVI and yield of wheat crops occurs at the height of the growing season when NDVI values and photosynthetic activity of the wheat plants are at their relative maximum. At the same time NDVI saturates in very dense and vigorous (healthy, green) canopies such as wheat fields during the seasonal peak and shows significantly reduced sensitivity to further increases in photosynthetic activity. In this study we compare the performance of different vegetation indices derived from space-borne red and near-infrared spectral reflectance measurements for wheat yield forecasting in the Punjab Province, Pakistan. Areas covered by wheat crop each year were determined using a time series of MODIS 8-day composites at 250 m resolution converted to temporal metrics and classified using a bagged decision tree approach, driven by classified multi-temporal Landsat scenes. Within the wheat areas we analyze and compare wheat yield forecasts derived from three different satellite-based vegetation indices at the peak of the growing season. We regressed in turn NDVI, Wide Dynamic Range Vegetation Index (WDRVI) and the Vegetation Condition Index (VCI) from the four years preceding the wheat growing season 2011/12 against reported yield values and applied the regression equations to forecast wheat yield for the 2011/12 season per district for each of 36 Punjab districts. Yield forecasts overall

The importance of environmental variability and management control error to optimal harvest policies

USGS Publications Warehouse

Hunter, C.M.; Runge, M.C.

2004-01-01

State-dependent strategies (SDSs) are the most general form of harvest policy because they allow the harvest rate to depend, without constraint, on the state of the system. State-dependent strategies that provide an optimal harvest rate for any system state can be calculated, and stochasticity can be appropriately accommodated in this optimization. Stochasticity poses 2 challenges to harvest policies: (1) the population will never be at the equilibrium state; and (2) stochasticity induces uncertainty about future states. We investigated the effects of 2 types of stochasticity, environmental variability and management control error, on SDS harvest policies for a white-tailed deer (Odocoileus virginianus) model, and contrasted these with a harvest policy based on maximum sustainable yield (MSY). Increasing stochasticity resulted in more conservative SDSs; that is, higher population densities were required to support the same harvest rate, but these effects were generally small. As stochastic effects increased, SDSs performed much better than MSY. Both deterministic and stochastic SDSs maintained maximum mean annual harvest yield (AHY) and optimal equilibrium population size (Neq) in a stochastic environment, whereas an MSY policy could not. We suggest 3 rules of thumb for harvest management of long-lived vertebrates in stochastic systems: (1) an SDS is advantageous over an MSY policy, (2) using an SDS rather than an MSY is more important than whether a deterministic or stochastic SDS is used, and (3) for SDSs, rankings of the variability in management outcomes (e.g., harvest yield) resulting from parameter stochasticity can be predicted by rankings of the deterministic elasticities.

Site-Specific Management of Miscanthus Genotypes for Combustion and Anaerobic Digestion: A Comparison of Energy Yields.

PubMed

Kiesel, Andreas; Nunn, Christopher; Iqbal, Yasir; Van der Weijde, Tim; Wagner, Moritz; Özgüven, Mensure; Tarakanov, Ivan; Kalinina, Olena; Trindade, Luisa M; Clifton-Brown, John; Lewandowski, Iris

2017-01-01

In Europe, the perennial C 4 grass miscanthus is currently mainly cultivated for energy generation via combustion. In recent years, anaerobic digestion has been identified as a promising alternative utilization pathway. Anaerobic digestion produces a higher-value intermediate (biogas), which can be upgraded to biomethane, stored in the existing natural gas infrastructure and further utilized as a transport fuel or in combined heat and power plants. However, the upgrading of the solid biomass into gaseous fuel leads to conversion-related energy losses, the level of which depends on the cultivation parameters genotype, location, and harvest date. Thus, site-specific crop management needs to be adapted to the intended utilization pathway. The objectives of this paper are to quantify (i) the impact of genotype, location and harvest date on energy yields of anaerobic digestion and combustion and (ii) the conversion losses of upgrading solid biomass into biogas. For this purpose, five miscanthus genotypes (OPM 3, 6, 9, 11, 14), three cultivation locations (Adana, Moscow, Stuttgart), and up to six harvest dates (August-March) were assessed. Anaerobic digestion yielded, on average, 35% less energy than combustion. Genotype, location, and harvest date all had significant impacts on the energy yield. For both, this is determined by dry matter yield and ash content and additionally by substrate-specific methane yield for anaerobic digestion and moisture content for combustion. Averaged over all locations and genotypes, an early harvest in August led to 25% and a late harvest to 45% conversion losses. However, each utilization option has its own optimal harvest date, determined by biomass yield, biomass quality, and cutting tolerance. By applying an autumn green harvest for anaerobic digestion and a delayed harvest for combustion, the conversion-related energy loss was reduced to an average of 18%. This clearly shows that the delayed harvest required to maintain biomass

A piezoelectric energy harvester for broadband rotational excitation using buckled beam

NASA Astrophysics Data System (ADS)

Xie, Zhengqiu; Kitio Kwuimy, C. A.; Wang, Zhiguo; Huang, Wenbin

2018-01-01

This paper proposes a rotational energy harvester using a piezoelectric bistable buckled beam to harvest low-speed rotational energy. The proposed harvester consists of a piezoelectric buckled beam with a center magnet, and a rotary magnet pair with opposite magnetic poles mounted on a revolving host. The magnetic plucking is used to harvest the angular kinetic energy of the host. The nonlinear snap-through mechanism is utilized to improve the vibration displacement and output voltage of the piezoelectric layer over a wide rotation frequency range. Theoretical simulation and experimental results show that the proposed energy harvester can yield a stable average output power ranging between 6.91-48.01 μW over a rotation frequency range of 1-14 Hz across a resistance load of 110 kΩ. Furthermore, dual attraction magnets were employed to overcome the suppression phenomenon at higher frequencies, which yields a broadband and flat frequency response over 6-14 Hz with the output power reaching 42.19-65.44 μW, demonstrating the great potential of the bistable buckled beam for wideband rotation motion energy harvesting.

Field-based high throughput phenotyping rapidly identifies genomic regions controlling yield components in rice

PubMed Central

Tanger, Paul; Klassen, Stephen; Mojica, Julius P.; Lovell, John T.; Moyers, Brook T.; Baraoidan, Marietta; Naredo, Maria Elizabeth B.; McNally, Kenneth L.; Poland, Jesse; Bush, Daniel R.; Leung, Hei; Leach, Jan E.; McKay, John K.

2017-01-01

To ensure food security in the face of population growth, decreasing water and land for agriculture, and increasing climate variability, crop yields must increase faster than the current rates. Increased yields will require implementing novel approaches in genetic discovery and breeding. Here we demonstrate the potential of field-based high throughput phenotyping (HTP) on a large recombinant population of rice to identify genetic variation underlying important traits. We find that detecting quantitative trait loci (QTL) with HTP phenotyping is as accurate and effective as traditional labor-intensive measures of flowering time, height, biomass, grain yield, and harvest index. Genetic mapping in this population, derived from a cross of an modern cultivar (IR64) with a landrace (Aswina), identified four alleles with negative effect on grain yield that are fixed in IR64, demonstrating the potential for HTP of large populations as a strategy for the second green revolution. PMID:28220807

Potential of four corn varieties at different harvest stages for tropical silage production in Malaysia.

PubMed

Nazli, Muhamad Hazim; Abdul Halim, Ridzwan; Abdullah, Amin Mahir; Husin, Ghazali; Samsudin, Anjas Asmara

2018-05-31

Apart from various climatic differences, corn harvest stage and varieties are two major factors that can influence the yield and quality of corn silage in the tropics. A study was conducted to determine the optimum harvest stage of four corn varieties for tropical silage production in Malaysia. Using a split plot design, corn was harvested at four growth stages; silking, milk, dough and dent stages using four varieties; Sweet Corn hybrid 926, Suwan, Breeding Test Line (BTL) 1 and BTL 2. The treatments were then analysed based on the plant growth performance, yield, nutritive and feeding values followed by a financial feasibility study for potential commercialization. Significant differences and interactions were detected across the parameters suggesting varying responses among the varieties towards the harvest stages. Sweet Corn was best harvested early in the dough stage due to high dry matter (DM) yield, digestible nutrient and energy content with low fibre portion. Suwan was recommended to be harvested at the dent stage when it gave the highest DM yield with optimum digestible nutrient and energy content with low acid detergent fibre (ADF). BTL 1 and BTL 2 varieties can either be harvested at dough or dent stages as the crude protein (CP), fibre, DM yield, DM content, digestible nutrient and energy were not significantly different at both stages. Further financial analysis showed that only Sweet Corn production was not financially feasible while Suwan had the best financial appraisal values among the grain varieties. In conclusion, only the grain varieties tested had the potential for silage making according to their optimum harvest stage but Suwan is highly recommended for commercialization as it was the most profitable.

Winter wheat yield estimation of remote sensing research based on WOFOST crop model and leaf area index assimilation

NASA Astrophysics Data System (ADS)

Chen, Yanling; Gong, Adu; Li, Jing; Wang, Jingmei

2017-04-01

Accurate crop growth monitoring and yield predictive information are significant to improve the sustainable development of agriculture and ensure the security of national food. Remote sensing observation and crop growth simulation models are two new technologies, which have highly potential applications in crop growth monitoring and yield forecasting in recent years. However, both of them have limitations in mechanism or regional application respectively. Remote sensing information can not reveal crop growth and development, inner mechanism of yield formation and the affection of environmental meteorological conditions. Crop growth simulation models have difficulties in obtaining data and parameterization from single-point to regional application. In order to make good use of the advantages of these two technologies, the coupling technique of remote sensing information and crop growth simulation models has been studied. Filtering and optimizing model parameters are key to yield estimation by remote sensing and crop model based on regional crop assimilation. Winter wheat of GaoCheng was selected as the experiment object in this paper. And then the essential data was collected, such as biochemical data and farmland environmental data and meteorological data about several critical growing periods. Meanwhile, the image of environmental mitigation small satellite HJ-CCD was obtained. In this paper, research work and major conclusions are as follows. (1) Seven vegetation indexes were selected to retrieve LAI, and then linear regression model was built up between each of these indexes and the measured LAI. The result shows that the accuracy of EVI model was the highest (R2=0.964 at anthesis stage and R2=0.920 at filling stage). Thus, EVI as the most optimal vegetation index to predict LAI in this paper. (2) EFAST method was adopted in this paper to conduct the sensitive analysis to the 26 initial parameters of the WOFOST model and then a sensitivity index was constructed

Maximal yields from multispecies fisheries systems: rules for systems with multiple trophic levels.

PubMed

Matsuda, Hiroyuki; Abrams, Peter A

2006-02-01

Increasing centralization of the control of fisheries combined with increased knowledge of food-web relationships is likely to lead to attempts to maximize economic yield from entire food webs. With the exception of predator-prey systems, we lack any analysis of the nature of such yield-maximizing strategies. We use simple food-web models to investigate the nature of yield- or profit-maximizing exploitation of communities including two types of three-species food webs and a variety of six-species systems with as many as five trophic levels. These models show that, for most webs, relatively few species are harvested at equilibrium and that a significant fraction of the species is lost from the web. These extinctions occur for two reasons: (1) indirect effects due to harvesting of species that had positive effects on the extinct species, and (2) intentional eradication of species that are not themselves valuable, but have negative effects on more valuable species. In most cases, the yield-maximizing harvest involves taking only species from one trophic level. In no case was an unharvested top predator part of the yield-maximizing strategy. Analyses reveal that the existence of direct density dependence in consumers has a large effect on the nature of the optimal harvest policy, typically resulting in harvest of a larger number of species. A constraint that all species must be retained in the system (a "constraint of biodiversity conservation") usually increases the number of species and trophic levels harvested at the yield-maximizing policy. The reduction in total yield caused by such a constraint is modest for most food webs but can be over 90% in some cases. Independent harvesting of species within the web can also cause extinctions but is less likely to do so.

Piezoelectric energy harvesting from an L-shaped beam-mass structure

NASA Astrophysics Data System (ADS)

Erturk, Alper; Renno, Jamil M.; Inman, Daniel J.

2008-03-01

Cantilevered piezoelectric harvesters have been extensively considered in the energy harvesting literature. Mostly, a traditional cantilevered beam with one or more piezoceramic layers is located on a vibrating host structure. Motion of the host structure results in vibrations of the harvester beam and that yields an alternating voltage output. As an alternative to classical cantilevered beams, this paper presents a novel harvesting device; a flexible L-shaped beam-mass structure that can be tuned to have a two-to-one internal resonance to a primary resonance ω II ≅ 2ω I which is not possible for classical cantilevers). The L-shaped structure has been well investigated in the literature of nonlinear dynamics since the two-to-one internal resonance, along with the consideration of quadratic nonlinearities, may yield modal energy exchange (for excitation frequency ω≅ ω Ior the so-called saturation phenomenon (for ω≅ω II). As a part of our ongoing research on piezoelectric energy harvesting, we are investigating the possibility of improving the electrical outputs in energy harvesting by employing these features of the L-shaped structure. This paper aims to introduce the idea, describes the important features of the L-shaped harvester configuration and develops a linear distributed parameter model for predicting the electromechanically coupled response. In addition, this work proposes a direct application of the L-shaped piezoelectric energy harvester configuration for use as landing gears in unmanned air vehicle applications.

Marine microalgae Nannochloropsis oculata biomass harvesting using ultrafiltration in cross-flow mode

NASA Astrophysics Data System (ADS)

Devianto, L. A.; Aprilia, D. N.; Indriani, D. W.; Sukarni, S.; Sumarlan, S. H.; Wibisono, Y.

2018-03-01

Microalgae is a potential bioenergy source. It can grows rapidly, even it could be harvested within 7 days. Harvesting is an important part of microalgae cultivation due to the method used. It should be undamaging toward essential content of microalgae and should produces high yields of biomass. In this study, the harvesting of Nannochloropsis oculata was carried out using capillary ultrafiltration in cross flow mode. This study aims to test ultrafiltration membrane performance in Nannochloropsis oculata harvesting accompanied by Backwash and Non-Backwash modes and to analyse its total lipid content. The harvest was done under 1; 1.5; and 2 bar of trans membrane pressure. Some observed parameters were permeate flux, cell density, biomass recovery, microalgae’s dry weight, yield, and total lipid content. The application of high pressure and backwashed treatment have boosted slurry production time which lead to microalgae’s biomass abundance. The result showed that the best treatment of Nannochloropsis oculata harvesting using capillary ultrafiltration membrane in cross flow mode is under 2 bar of pressure with backwashed treatment. This is the fastest condition to produce slurry within 1800 s with the highest recovery percentage 79.50%, 16.05 × 106 cell/ml of post-treatment cell density, 6.8 grams of biomass’ dry weight, 22.66 % of yield, and 2.52 % of total lipid content.

Switchgrass Biomass Quality as Affected by Nitrogen Rate, Harvest Time, and Storage

DOE PAGES

Ibrahim, Mostafa; Hong, Chang Oh.; Singh, Shikha; ...

2017-01-25

The purpose of this study was to assess the changes in switchgrass (Panicum virgatum L.) biomass quality as affected by N rate, harvest time, and storage. This research was conducted near Bristol, SD, in 2010 and 2011. Treatments included three N rates (0, 56, and 112 kg N ha –1) applied annually and each N rate replicated four times. After a killing frost, all of the plots were harvested and baled in large round bales in October 2010 and November 2011. An area of about 30 m 2 from each plot was left unharvested to represent storage of standing switchgrassmore » over the winter and to determine dry matter yields. Switchgrass was analyzed for hemicellulose, cellulose, lignin, mineral elements, N, and C. In the first season, storage of the fall harvested switchgrass bales numerically increased the concentrations of hemicellulose, lignin, and N. In the second season, they increased significantly. Mineral elements significantly increased in both sampling seasons. Delaying harvest until spring decreased lignin, N, and mineral elements concentration, and increased cellulose and hemicellulose concentrations, but also reduced biomass yield. Results from this study suggest that delaying the switchgrass harvest until spring increased the overall feedstock quality for ethanol production, but yield reductions must be considered to determine the overall economic impact of a delayed harvest.« less

Switchgrass Biomass Quality as Affected by Nitrogen Rate, Harvest Time, and Storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ibrahim, Mostafa; Hong, Chang Oh.; Singh, Shikha

The purpose of this study was to assess the changes in switchgrass (Panicum virgatum L.) biomass quality as affected by N rate, harvest time, and storage. This research was conducted near Bristol, SD, in 2010 and 2011. Treatments included three N rates (0, 56, and 112 kg N ha –1) applied annually and each N rate replicated four times. After a killing frost, all of the plots were harvested and baled in large round bales in October 2010 and November 2011. An area of about 30 m 2 from each plot was left unharvested to represent storage of standing switchgrassmore » over the winter and to determine dry matter yields. Switchgrass was analyzed for hemicellulose, cellulose, lignin, mineral elements, N, and C. In the first season, storage of the fall harvested switchgrass bales numerically increased the concentrations of hemicellulose, lignin, and N. In the second season, they increased significantly. Mineral elements significantly increased in both sampling seasons. Delaying harvest until spring decreased lignin, N, and mineral elements concentration, and increased cellulose and hemicellulose concentrations, but also reduced biomass yield. Results from this study suggest that delaying the switchgrass harvest until spring increased the overall feedstock quality for ethanol production, but yield reductions must be considered to determine the overall economic impact of a delayed harvest.« less

Cotton harvest at 40% versus 75% boll-splitting on yield and economic return under standard and proactive boll weevil (Coleoptera: Curculionidae) spray regimes.

PubMed

Showler, A T; Robinson, J R C

2008-10-01

The standard practice of two or three preemptive insecticide applications at the start of pinhead (1-2-mm-diameter) squaring followed by threshold-triggered (when 10% of randomly selected squares have oviposition punctures) insecticide applications for boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), control does not provide reliable protection of cotton, Gossypium hirsutum L., lint production. This study, conducted during 2004 and 2005, showed that three to six fewer spray applications in a "proactive" approach, in which spraying began at the start of large (5.5-8-mm-diameter) square formation and continued at approximately 7-d intervals while large squares were abundant, resulted in fewer infested squares and 1.4- to 1.7-fold more lint than the standard treatment. Fewer sprays and increased yield made proactive spraying significantly more profitable than the standard approach, which resulted in relatively low or negative economic returns. Harvest at 75% boll-split in the proactive spray regime of 2005 resulted in four-fold greater economic return than cotton harvested at 40% boll-split because of improved protection of large squares and the elimination of late-season sprays inherent to standard spray regime despite the cost of an extra irrigation in the 75% boll-split treatments. The earlier, 40% harvest trigger does not avoid high late-season boll weevil pressure, which exerts less impact on bolls, the predominant form of fruiting body at that time, than on squares. Proactive spraying and harvest timing are based on an important relationship between nutrition, boll weevil reproduction, and economic inputs; therefore, the tactic of combining proaction with harvest at 75% boll-split is applicable where boll weevils are problematic regardless of climate or region, or whether an eradication program is ongoing.

Site-Specific Management of Miscanthus Genotypes for Combustion and Anaerobic Digestion: A Comparison of Energy Yields

PubMed Central

Kiesel, Andreas; Nunn, Christopher; Iqbal, Yasir; Van der Weijde, Tim; Wagner, Moritz; Özgüven, Mensure; Tarakanov, Ivan; Kalinina, Olena; Trindade, Luisa M.; Clifton-Brown, John; Lewandowski, Iris

2017-01-01

In Europe, the perennial C4 grass miscanthus is currently mainly cultivated for energy generation via combustion. In recent years, anaerobic digestion has been identified as a promising alternative utilization pathway. Anaerobic digestion produces a higher-value intermediate (biogas), which can be upgraded to biomethane, stored in the existing natural gas infrastructure and further utilized as a transport fuel or in combined heat and power plants. However, the upgrading of the solid biomass into gaseous fuel leads to conversion-related energy losses, the level of which depends on the cultivation parameters genotype, location, and harvest date. Thus, site-specific crop management needs to be adapted to the intended utilization pathway. The objectives of this paper are to quantify (i) the impact of genotype, location and harvest date on energy yields of anaerobic digestion and combustion and (ii) the conversion losses of upgrading solid biomass into biogas. For this purpose, five miscanthus genotypes (OPM 3, 6, 9, 11, 14), three cultivation locations (Adana, Moscow, Stuttgart), and up to six harvest dates (August–March) were assessed. Anaerobic digestion yielded, on average, 35% less energy than combustion. Genotype, location, and harvest date all had significant impacts on the energy yield. For both, this is determined by dry matter yield and ash content and additionally by substrate-specific methane yield for anaerobic digestion and moisture content for combustion. Averaged over all locations and genotypes, an early harvest in August led to 25% and a late harvest to 45% conversion losses. However, each utilization option has its own optimal harvest date, determined by biomass yield, biomass quality, and cutting tolerance. By applying an autumn green harvest for anaerobic digestion and a delayed harvest for combustion, the conversion-related energy loss was reduced to an average of 18%. This clearly shows that the delayed harvest required to maintain biomass

Simulating the effects of climate and agricultural management practices on global crop yield

NASA Astrophysics Data System (ADS)

Deryng, D.; Sacks, W. J.; Barford, C. C.; Ramankutty, N.

2011-06-01

Climate change is expected to significantly impact global food production, and it is important to understand the potential geographic distribution of yield losses and the means to alleviate them. This study presents a new global crop model, PEGASUS 1.0 (Predicting Ecosystem Goods And Services Using Scenarios) that integrates, in addition to climate, the effect of planting dates and cultivar choices, irrigation, and fertilizer application on crop yield for maize, soybean, and spring wheat. PEGASUS combines carbon dynamics for crops with a surface energy and soil water balance model. It also benefits from the recent development of a suite of global data sets and analyses that serve as model inputs or as calibration data. These include data on crop planting and harvesting dates, crop-specific irrigated areas, a global analysis of yield gaps, and harvested area and yield of major crops. Model results for present-day climate and farm management compare reasonably well with global data. Simulated planting and harvesting dates are within the range of crop calendar observations in more than 75% of the total crop-harvested areas. Correlation of simulated and observed crop yields indicates a weighted coefficient of determination, with the weighting based on crop-harvested area, of 0.81 for maize, 0.66 for soybean, and 0.45 for spring wheat. We found that changes in temperature and precipitation as predicted by global climate models for the 2050s lead to a global yield reduction if planting and harvesting dates remain unchanged. However, adapting planting dates and cultivar choices increases yield in temperate regions and avoids 7-18% of global losses.

Increased water yields following harvesting operations on a drained coastal watershed

Treesearch

Johnny M. Grace; R.W. Skaggs; H.R. Malcom; G.M. Chescheir; D.K. Cassel

2003-01-01

Forest harvesting operations have been reported to affect annual and seasonal outflow characteristics from drained forest watersheds. Increases in forest outflow, nutrient concentrations, and suspended sediments are commonly seen as a result of these forest management activities. Thus, it is important to assess the impact of forest management activities on hydrology,...

A Five-Year Assessment of Corn Stover Harvest in Central Iowa, USA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Douglas L. Karlen; Stuart J. Birell; J. Richard Hess

Sustainable feedstock harvest strategies are needed to ensure bioenergy production does not irreversibly degrade soil resources. The objective for this study was to document corn (Zea mays L.) grain and stover fraction yields, plant nutrient removal and replacement costs, feedstock quality, soil-test changes, and soil quality indicator response to four stover harvest strategies for continuous corn and a corn-soybean [Glycine max. (L.) Merr.] rotation. The treatments included collecting (1) all standing plant material above a stubble height of 10 cm (whole plant), (2) the upper-half by height (ear shank upward), (3) the lower-half by height (from the 10 cm stubblemore » height to just below the earshank), or (4) no removal. Collectable biomass from Treatment 2 averaged 3.9 ({+-}0.8) Mg ha{sup -1} for continuous corn (2005 through 2009), and 4.8 ({+-}0.4) Mg ha{sup -1} for the rotated corn (2005, 2007, and 2009). Compared to harvesting only the grain, collecting stover increased the average N-P-K removal by 29, 3 and 34 kg ha{sup -1} for continuous corn and 42, 3, and 34 kg ha{sup -1} for rotated corn, respectively. Harvesting the lower-half of the corn plant (Treatment 3) required two passes, resulted in frequent plugging of the combine, and provided a feedstock with low quality for conversion to biofuel. Therefore, Treatment 3 was replaced by a 'cobs-only' harvest starting in 2009. Structural sugars glucan and xylan accounted for up to 60% of the chemical composition, while galactan, arabinan, and mannose constituted less than 5% of the harvest fractions collected from 2005 through 2008. Soil-test data from samples collected after the first harvest (2005) revealed low to very low plant-available P and K levels which reduced soybean yield in 2006 after harvesting the whole-plant in 2005. Average continuous corn yields were 21% lower than rotated yields with no significant differences due to stover harvest. Rotated corn yields in 2009 showed some significant

Legume-Cereal Intercropping Improves Forage Yield, Quality and Degradability.

PubMed

Zhang, Jie; Yin, Binjie; Xie, Yuhuai; Li, Jing; Yang, Zaibin; Zhang, Guiguo

2015-01-01

Intercropping legume with cereal is an extensively applied planting pattern in crop cultivation. However, forage potential and the degradability of harvested mixtures from intercropping system remain unclear. To investigate the feasibility of applying an intercropping system as a forage supply source to ruminants, two consecutive experiments (experiments 1 and 2) involving a field cultivation trial and a subsequent in vivo degradable experiment were conducted to determine the forage production performance and the ruminally degradable characteristics of a harvested mixture from an alfalfa/corn-rye intercropping system. In experiment 1, the intercropping system was established by alternating alfalfa and corn or rye with a row ratio of 5:2. Dry matter (DM) and nutrient yields were determined. In experiment 2, forages harvested from the different treatments were used as feedstuff to identify nutrient degradation kinetics and distribution of components between the rapidly degradable (a), potentially degradable (b) and the degradation rate constant (c) of 'b' fraction by in sacco method in Small-Tail Han wether Sheep. The intercropping system of alfalfa and corn-rye provided higher forage production performance with net increases of 9.52% and 34.81% in DM yield, 42.13% and 16.74% in crude protein (CP) yield, 25.94% and 69.99% in degradable DM yield, and 16.96% and 5.50% in degradable CP yield than rotation and alfalfa sole cropping systems, respectively. In addition, the harvest mixture from intercropping system also had greater 'a' fraction, 'b' fraction, 'c' values, and effective degradability (E value) of DM and CP than corn or rye hay harvested from rotation system. After 48-h exposure to rumen microbes, intercropping harvest materials were degraded to a higher extent than separately degraded crop stems from the sole system as indicated by visual microscopic examination with more tissues disappeared. Thus, the intercropping of alfalfa and corn-rye exhibited a greater

Field-based high throughput phenotyping rapidly identifies genomic regions controlling yield components in rice

DOE PAGES

Tanger, Paul; Klassen, Stephen; Mojica, Julius P.; ...

2017-02-21

In order to ensure food security in the face of population growth, decreasing water and land for agriculture, and increasing climate variability, crop yields must increase faster than the current rates. Increased yields will require implementing novel approaches in genetic discovery and breeding. We demonstrate the potential of field-based high throughput phenotyping (HTP) on a large recombinant population of rice to identify genetic variation underlying important traits. We find that detecting quantitative trait loci (QTL) with HTP phenotyping is as accurate and effective as traditional labor- intensive measures of flowering time, height, biomass, grain yield, and harvest index. Furthermore, geneticmore » mapping in this population, derived from a cross of an modern cultivar (IR64) with a landrace (Aswina), identified four alleles with negative effect on grain yield that are fixed in IR64, demonstrating the potential for HTP of large populations as a strategy for the second green revolution.« less

Field-based high throughput phenotyping rapidly identifies genomic regions controlling yield components in rice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tanger, Paul; Klassen, Stephen; Mojica, Julius P.

In order to ensure food security in the face of population growth, decreasing water and land for agriculture, and increasing climate variability, crop yields must increase faster than the current rates. Increased yields will require implementing novel approaches in genetic discovery and breeding. We demonstrate the potential of field-based high throughput phenotyping (HTP) on a large recombinant population of rice to identify genetic variation underlying important traits. We find that detecting quantitative trait loci (QTL) with HTP phenotyping is as accurate and effective as traditional labor- intensive measures of flowering time, height, biomass, grain yield, and harvest index. Furthermore, geneticmore » mapping in this population, derived from a cross of an modern cultivar (IR64) with a landrace (Aswina), identified four alleles with negative effect on grain yield that are fixed in IR64, demonstrating the potential for HTP of large populations as a strategy for the second green revolution.« less

Watershed sustainability: Downstream effects of timber harvest in the Ozarks of Missouri

USGS Publications Warehouse

Jacobson, Robert B.

2004-01-01

The downstream effects of timber harvest in the Ozarks of Missouri can be evaluated by analogy to other geographic areas and by historical analysis of responses to past land use activities. Based on research from other geographic regions, timber harvest in the Ozarks would be expected to have minor effects on annual water yield and dissolved-phase water quality. The potential exists for haul roads to increase stormflow discharges and sediment yields. Of the possible downstream effects, sediment yield is potentially the most severe and difficult to predict; siting and design of roads are probably the most critical management concerns for minimizing downstream effects. Historical analysis shows that Ozark streams have been destabilized by past land use practices, primarily in the riparian zone. Therefore, present-day timber harvest takes place in a landscape where streams have lowered resilience to disturbance. Predictions of future downstream effects of timber harvest in the Ozarks are complicated by the inherent complexity of cumulative watershed effects and the lack of detailed, long-term instrumental records at appropriate scales.

Modeling the Complex Impacts of Timber Harvests to Find Optimal Management Regimes for Amazon Tidal Floodplain Forests

PubMed Central

Fortini, Lucas B.; Cropper, Wendell P.; Zarin, Daniel J.

2015-01-01

At the Amazon estuary, the oldest logging frontier in the Amazon, no studies have comprehensively explored the potential long-term population and yield consequences of multiple timber harvests over time. Matrix population modeling is one way to simulate long-term impacts of tree harvests, but this approach has often ignored common impacts of tree harvests including incidental damage, changes in post-harvest demography, shifts in the distribution of merchantable trees, and shifts in stand composition. We designed a matrix-based forest management model that incorporates these harvest-related impacts so resulting simulations reflect forest stand dynamics under repeated timber harvests as well as the realities of local smallholder timber management systems. Using a wide range of values for management criteria (e.g., length of cutting cycle, minimum cut diameter), we projected the long-term population dynamics and yields of hundreds of timber management regimes in the Amazon estuary, where small-scale, unmechanized logging is an important economic activity. These results were then compared to find optimal stand-level and species-specific sustainable timber management (STM) regimes using a set of timber yield and population growth indicators. Prospects for STM in Amazonian tidal floodplain forests are better than for many other tropical forests. However, generally high stock recovery rates between harvests are due to the comparatively high projected mean annualized yields from fast-growing species that effectively counterbalance the projected yield declines from other species. For Amazonian tidal floodplain forests, national management guidelines provide neither the highest yields nor the highest sustained population growth for species under management. Our research shows that management guidelines specific to a region’s ecological settings can be further refined to consider differences in species demographic responses to repeated harvests. In principle, such fine

Modeling the complex impacts of timber harvests to find optimal management regimes for Amazon tidal floodplain forests

USGS Publications Warehouse

Fortini, Lucas B.; Cropper, Wendell P.; Zarin, Daniel J.

2015-01-01

At the Amazon estuary, the oldest logging frontier in the Amazon, no studies have comprehensively explored the potential long-term population and yield consequences of multiple timber harvests over time. Matrix population modeling is one way to simulate long-term impacts of tree harvests, but this approach has often ignored common impacts of tree harvests including incidental damage, changes in post-harvest demography, shifts in the distribution of merchantable trees, and shifts in stand composition. We designed a matrix-based forest management model that incorporates these harvest-related impacts so resulting simulations reflect forest stand dynamics under repeated timber harvests as well as the realities of local smallholder timber management systems. Using a wide range of values for management criteria (e.g., length of cutting cycle, minimum cut diameter), we projected the long-term population dynamics and yields of hundreds of timber management regimes in the Amazon estuary, where small-scale, unmechanized logging is an important economic activity. These results were then compared to find optimal stand-level and species-specific sustainable timber management (STM) regimes using a set of timber yield and population growth indicators. Prospects for STM in Amazonian tidal floodplain forests are better than for many other tropical forests. However, generally high stock recovery rates between harvests are due to the comparatively high projected mean annualized yields from fast-growing species that effectively counterbalance the projected yield declines from other species. For Amazonian tidal floodplain forests, national management guidelines provide neither the highest yields nor the highest sustained population growth for species under management. Our research shows that management guidelines specific to a region’s ecological settings can be further refined to consider differences in species demographic responses to repeated harvests. In principle, such fine

Impact of Harvesting on Sediment and Runoff Production on a Piedmont Site in Alabama

Treesearch

Johnny M. Grace; Emily A. Carter

2000-01-01

This study was performed in Lee County, Alabama to investigate the impact of harvesting a 20-year-old loblolly pine (Pinus taeda L.) plantation on sediment and runoff yield. Sediment and runoff yield responses on harvest areas was compared to that of undisturbed areas. Impacts were evaluated by establishing and monitoring isolated small plots, 2-m...

Do Yield and Quality of Big Bluestem and Switchgrass Feedstock Decline over Winter?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Jane M. F.; Gresham, Garold L.

Switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerdardii Vitman) are potential perennial bioenergy feedstocks. Feedstock storage limitations, labor constraints for harvest, and environmental benefits provided by perennials are rationales for developing localized perennial feedstock as an alternative or in conjunction with annual feedstocks (i.e., crop residues). Little information is available on yield, mineral, and thermochemical properties of native species as related to harvest time. The study’s objectives were to compare the feedstock quantity and quality between grasses harvested in the fall or the following spring. It was hypothesized that biomass yield may decline, but translocation and/or leaching of mineralsmore » from the feedstock would improve feedstock quality. Feedstock yield did not differ by crop, harvest time, or their interactions. Both grasses averaged 6.0 Mg ha-1 (fall) and 5.4 Mg ha-1 (spring) with similar high heating value (17.7 MJ kg-1). The K/(Ca + Mg) ratio, used as a quality indicator declined to below a 0.5 threshold, but energy yield (Megajoule per kilogram) decreased 13% by delaying harvest until spring. Only once during the four study-years were conditions ideal for early spring harvest, in contrast during another spring, very muddy conditions resulted in excessive soil contamination. Early spring harvest may be hampered by late snow, lodging, and muddy conditions that may delay or prevent harvest, and result in soil contamination of the feedstock. However, reducing slagging/fouling potential and the mass of mineral nutrients removed from the field without a dramatic loss in biomass or caloric content are reasons to delay harvest until spring.« less

Determination of the Optimum Harvest Window for Apples Using the Non-Destructive Biospeckle Method.

PubMed

Skic, Anna; Szymańska-Chargot, Monika; Kruk, Beata; Chylińska, Monika; Pieczywek, Piotr Mariusz; Kurenda, Andrzej; Zdunek, Artur; Rutkowski, Krzysztof P

2016-05-10

Determination of the optimum harvest window plays a key role in the agro-food chain as the quality of fruit depends on the right harvesting time and appropriate storage conditions during the postharvest period. Usually, indices based on destructive measurements are used for this purpose, like the De Jager Index (PFW-1), FARS index and the most popular Streif Index. In this study, we proposed a biospeckle method for the evaluation of the optimum harvest window (OHW) of the "Ligol" and "Szampion" apple cultivars. The experiment involved eight different maturity stages, of which four were followed by long cold storage and shelf life to assist the determination of the optimum harvest window. The biospeckle activity was studied in relation to standard quality attributes (firmness, acidity, starch, soluble solids content, Streif Index) and physiological parameters (respiration and ethylene emission) of both apple cultivars. Changes of biospeckle activity (BA) over time showed moderate relationships with biochemical changes during apple maturation and ripening. The harvest date suggested by the Streif Index and postharvest quality indicators matched with characteristic decrease in BA. The ability of biospeckle method to characterize the biological state of apples was confirmed by significant correlations of BA with firmness, starch index, total soluble solids and Streif Index, as well as good match with changes in carbon dioxide and ethylene emission. However, it should be noted that correlations between variables changing over time are not as meaningful as independent observations. Also, it is a well-known property of the Pearson's correlation that its value is highly susceptible to outlier data. Due to its non-selective nature the BA reflected only the current biological state of the fruit and could be affected by many other factors. The investigations showed that the optimum harvest window for apples was indicated by the characteristic drop of BA during pre-harvest

Determination of the Optimum Harvest Window for Apples Using the Non-Destructive Biospeckle Method

PubMed Central

Skic, Anna; Szymańska-Chargot, Monika; Kruk, Beata; Chylińska, Monika; Pieczywek, Piotr Mariusz; Kurenda, Andrzej; Zdunek, Artur; Rutkowski, Krzysztof P.

2016-01-01

Determination of the optimum harvest window plays a key role in the agro-food chain as the quality of fruit depends on the right harvesting time and appropriate storage conditions during the postharvest period. Usually, indices based on destructive measurements are used for this purpose, like the De Jager Index (PFW-1), FARS index and the most popular Streif Index. In this study, we proposed a biospeckle method for the evaluation of the optimum harvest window (OHW) of the “Ligol” and “Szampion” apple cultivars. The experiment involved eight different maturity stages, of which four were followed by long cold storage and shelf life to assist the determination of the optimum harvest window. The biospeckle activity was studied in relation to standard quality attributes (firmness, acidity, starch, soluble solids content, Streif Index) and physiological parameters (respiration and ethylene emission) of both apple cultivars. Changes of biospeckle activity (BA) over time showed moderate relationships with biochemical changes during apple maturation and ripening. The harvest date suggested by the Streif Index and postharvest quality indicators matched with characteristic decrease in BA. The ability of biospeckle method to characterize the biological state of apples was confirmed by significant correlations of BA with firmness, starch index, total soluble solids and Streif Index, as well as good match with changes in carbon dioxide and ethylene emission. However, it should be noted that correlations between variables changing over time are not as meaningful as independent observations. Also, it is a well-known property of the Pearson’s correlation that its value is highly susceptible to outlier data. Due to its non-selective nature the BA reflected only the current biological state of the fruit and could be affected by many other factors. The investigations showed that the optimum harvest window for apples was indicated by the characteristic drop of BA during pre-harvest

Study of water stress effects in different growth stages on yield and yield components of different rice (Oryza sativa L.) cultivars.

PubMed

Sarvestani, Zinolabedin Tahmasebi; Pirdashti, Hemmatollah; Sanavy, Seyed Ali Mohammad Modarres; Balouchi, Hamidreza

2008-05-15

A field experiment was conducted during 2001-2003 to evaluate the effect of water stress on the yield and yield components of four rice cultivars commonly grown in Mazandaran province, Iran. In northern Iran irrigated lowland rice usually experiences water deficit during the growing season include of land preparation time, planting, tillering stage, flowering and grain filing period. Recently drought affected 20 of 28 provinces in Iran; with the southeastern, central and eastern parts of the country being most severely affected. The local and improved cultivars used were Tarom, Khazar, Fajr and Nemat. The different water stress conditions were water stress during vegetative, flowering and grain filling stages and well watered was the control. Water stress at vegetative stage significantly reduced plant height of all cultivars. Water stress at flowering stage had a greater grain yield reduction than water stress at other times. The reduction of grain yield largely resulted from the reduction in fertile panicle and filled grain percentage. Water deficit during vegetative, flowering and grain filling stages reduced mean grain yield by 21, 50 and 21% on average in comparison to control respectively. The yield advantage of two semidwarf varieties, Fajr and Nemat, were not maintained under drought stress. Total biomass, harvest index, plant height, filled grain, unfilled grain and 1000 grain weight were reduced under water stress in all cultivars. Water stress at vegetative stage effectively reduced total biomass due to decrease of photosynthesis rate and dry matter accumulation.

Harvesting cattail (Typha SPP) rhizomes as an alternative feedstock for alcohol production: modifications of potato harvester. Final report, July 1, 1981-December 31, 1982

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schertz, C.; Dubbe, D.; Pratt, D.

1983-03-01

The belowground portion of the cattail plant is a desirable alcohol fuel feedstock because of its high yield and sugar and starch content. Belowground yields of 22 Mt/hectare (10 tons/acre) with a sugar and starch content of 40% have been reported. In order to utilize this resource, a device must be developed to harvest it. The main objective of the project was to produce such a device based on existing harvesting technology which would be capable of removing and separating cattail rhizomes and shoot bases from the substrate in which they are growing. The device would eventually serve as amore » vital component of a harvesting machine for the entire plant. Associated objectives of this project included the gathering of information necessary to assess required draft forces, traction requirements, and soil moisture conditions.« less

Correlations and spatial variability of soil physical properties in harvested piedmont forests

Treesearch

Emily A. Carter; J.N. Shaw

2002-01-01

Soil response to timber harvest trafficking was similar for eroded soils in two locations of the Piedmont of Alabama. Pre-harvest and post-harvest data indicated compaction to be present to a depth of 40 cm as indicated by cone index measurements, with the most significant changes occurring in the upper 20 cm. The degree of spatial dependence differed among soil...

Effect of harvesting date on the composition and saccharification of Miscanthus x giganteus.

PubMed

Le Ngoc Huyen, T; Rémond, C; Dheilly, R M; Chabbert, B

2010-11-01

The chemical composition of the whole aerial biomass and isolated organs of Miscanthus x giganteus was examined for saccharification into fermentable sugars at early and late harvesting dates. Delayed harvest was mainly related to increased amounts of cell wall and ester-linked phenolic acids. Addition of an enzyme cocktail (cellulases, beta-glucosidase and xylanase) resulted in similar enzyme digestibilities at the two harvesting dates, ranging from 11-13% and 8-9% of the cellulose and arabinoxylan, respectively. However, the internodes, leaves and sheaths varied in cell wall content and composition and gave rise to different saccharification yields with internodes being the most recalcitrant organs. Non-cell wall fraction was estimated as the amount of material extracted by neutral detergent solution, and accounted for 23% of the whole aerial biomass harvested at an early date. However, saccharification yields from the miscanthus biomass did not change after soluble fraction removal. An ammonia pretreatment improved enzyme efficiency on early-harvested miscanthus, to a greater extent than on late-harvested biomass. This trend was confirmed for two different years of harvesting. Copyright 2010 Elsevier Ltd. All rights reserved.

Adjusting site index and age to account for genetic effects in yield equations for loblolly pine

Treesearch

Steven A. Knowe; G. Sam Foster

2010-01-01

Nine combinations of site index curves and age adjustments methods were evaluated for incorporating genetic effects for open-pollinated loblolly pine (Pinus taeda L.) families. An explicit yield system consisting of dominant height, basal area, and merchantable green weight functions was used to compare the accuracy of predictions associated with...

Using normalized difference vegetation index (NDVI) to estimate sugarcane yield and yield components

USDA-ARS?s Scientific Manuscript database

Sugarcane (Saccharum spp.) yield and yield components are important traits for growers and scientists to evaluate and select cultivars. Collection of these yield data would be labor intensive and time consuming in the early selection stages of sugarcane breeding cultivar development programs with a ...

Estimated harvesting on jellyfish in Sarawak

NASA Astrophysics Data System (ADS)

Bujang, Noriham; Hassan, Aimi Nuraida Ali

2017-04-01

There are three species of jellyfish recorded in Sarawak which are the Lobonema smithii (white jellyfish), Rhopilema esculenta (red jellyfish) and Mastigias papua. This study focused on two particular species which are L.smithii and R.esculenta. This study was done to estimate the highest carrying capacity and the population growth rate of both species by using logistic growth model. The maximum sustainable yield for the harvesting of this species was also determined. The unknown parameters in the logistic model were estimated using center finite different method. As for the results, it was found that the carrying capacity for L.smithii and R.esculenta were 4594.9246456819 tons and 5855.9894242086 tons respectively. Whereas, the population growth rate for both L.smithii and R.esculenta were estimated at 2.1800463754 and 1.144864086 respectively. Hence, the estimated maximum sustainable yield for harvesting for L.smithii and R.esculenta were 2504.2872047638 tons and 1676.0779949431 tons per year.

Seeing is believing I: The use of thermal sensing from satellite imagery to predict crop yield

NASA Astrophysics Data System (ADS)

B, Potgieter A.; D, Rodriguez; B, Power; J, Mclean; P, Davis

2014-02-01

Volatility in crop production has been part of the Australian environment since cropping began with the arrival of the first European settlers. Climate variability is the main factor affecting crop production at national, state and local scales. At field level spatial patterns on yield production are also determined by spatially changing soil properties in interaction with seasonal climate conditions and weather patterns at critical stages in the crop development. Here we used a combination of field level weather records, canopy characteristics, and satellite information to determine the spatial performance of a large field of wheat. The main objective of this research is to determine the ability of remote sensing technologies to capture yield losses due to water stress at the canopy level. The yield, canopy characteristics (i.e. canopy temperature and ground cover) and seasonal conditions of a field of wheat (~1400ha) (-29.402° South and 149.508°, New South Wales, Australia) were continuously monitored during the winter of 2011. Weather and crop variables were continuously monitored by installing three automatic weather stations in a transect covering different positions and soils in the landscape. Weather variables included rainfall, minimum and maximum temperatures and relative humidity, and crop characteristics included ground cover and canopy temperature. Satellite imagery Landsat TM 5 and 7 was collected at five different stages in the crop cycle. Weather variables and crop characteristics were used to calculate a crop stress index (CSI) at point and field scale (39 fields). Field data was used to validate a spatial satellite image derived index. Spatial yield data was downloaded from the harvester at the different locations in the field. We used the thermal band (land surface temperature, LST) and enhanced vegetation index (EVI) bands from the MODIS (250 m for visible bands and 1km for thermal band) and a derived EVI from Landsat TM 7 (25 m for visible and

Very high CO2 reduces photosynthesis, dark respiration and yield in wheat

NASA Technical Reports Server (NTRS)

Reuveni, J.; Bugbee, B.

1997-01-01

Although terrestrial CO2 concentrations, [CO2] are not expected to reach 1000 micromoles mol-1 for many decades, CO2 levels in closed systems such as growth chambers and glasshouses, can easily exceed this concentration. CO2 levels in life support systems in space can exceed 10000 micromoles mol-1 (1%). Here we studied the effect of six CO2 concentrations, from ambient up to 10000 micromoles mol-1, on seed yield, growth and gas exchange of two wheat cultivars (USU-Apogee and Veery-l0). Elevating [CO2] from 350 to 1000 micromoles mol-1 increased seed yield (by 33%), vegetative biomass (by 25%) and number of heads m-2 (by 34%) of wheat plants. Elevation of [CO2] from 1000 to 10000 micromoles mol-1 decreased seed yield (by 37%), harvest index (by 14%), mass per seed (by 9%) and number of seeds per head (by 29%). This very high [CO2] had a negligible, non-significant effect on vegetative biomass, number of heads m-2 and seed mass per head. A sharp decrease in seed yield, harvest index and seeds per head occurred by elevating [CO2] from 1000 to 2600 micromoles mol-1. Further elevation of [CO2] from 2600 to 10000 micromoles mol-1 caused a further but smaller decrease. The effect of CO2 on both wheat cultivars was similar for all growth parameters. Similarly there were no differences in the response to high [CO2] between wheat grown hydroponically in growth chambers under fluorescent lights and those grown in soilless media in a glasshouse under sunlight and high pressure sodium lamps. There was no correlation between high [CO2] and ethylene production by flag leaves or by wheat heads. Therefore, the reduction in seed set in wheat plants is not mediated by ethylene. The photosynthetic rate of whole wheat plants was 8% lower and dark respiration of the wheat heads 25% lower when exposed to 2600 micromoles mol-1 CO2 compared to ambient [CO2]. It is concluded that the reduction in the seed set can be mainly explained by the reduction in the dark respiration in wheat heads

Do wolves affect white-tailed buck harvest in northeastern Minnesota?

USGS Publications Warehouse

Mech, L. David; Nelson, Michael E.

2000-01-01

We used simple linear regression to analyze 8-23 years of data on a wolf (Canis lupus) population and human harvest of white-tailed deer (Odocoileus virginianus) bucks in northeastern Minnesota to determine any effects of wolves on buck harvesting. Over the long term, wolves accounted for at least 14-22% of the inter-year variation in buck harvest in the region, but an unknown amount of variation in hunter effort may have obscured any more precise estimate. For part of the area with poorest habitat, we found strong inverse relationships (r2 = 0.66-0.84) between annual wolf numbers and buck harvests from 1988 to 1995 when hunting pressure was considered relatively constant. However, in better habitat, where our buck harvest sample was larger, we found no evidence of wolves influencing buck harvest. Our findings tend to confirm the suitability of the Minnesota Department of Natural Resource's deer harvest regulations for a sustainable yield.

Limitation of Unloading in the Developing Grains Is a Possible Cause Responsible for Low Stem Non-structural Carbohydrate Translocation and Poor Grain Yield Formation in Rice through Verification of Recombinant Inbred Lines

PubMed Central

Li, Guohui; Pan, Junfeng; Cui, Kehui; Yuan, Musong; Hu, Qiuqian; Wang, Wencheng; Mohapatra, Pravat K.; Nie, Lixiao; Huang, Jianliang; Peng, Shaobing

2017-01-01

Remobilisation of non-structural carbohydrates (NSC) from leaves and stems and unloading into developing grains are essential for yield formation of rice. In present study, three recombinant inbred lines of rice, R91, R156 and R201 have been tested for source-flow-sink related attributes determining the nature of NSC accumulation and translocation at two nitrogen levels in the field. Compared to R91 and R156, R201 had lower grain filling percentage, harvest index, and grain yield. Meanwhile, R201 had significantly lower stem NSC translocation during grain filling stage. Grain filling percentage, harvest index, and grain yield showed the consistent trend with stem NSC translocation among the three lines. In comparison with R91 and R156, R201 had similarity in leaf area index, specific leaf weight, stem NSC concentration at heading, biomass, panicles m-2, spikelets per panicle, remobilization capability of assimilation in stems, sink capacity, sink activity, number and cross sectional area of small vascular bundles, greater number and cross sectional area of large vascular bundles, and higher SPAD, suggesting that source, flow, and sink were not the limiting factors for low stem NSC translocation and grain filling percentage of R201. However, R201 had significant higher stem and rachis NSC concentrations at maturity, which implied that unloading in the developing grains might result in low NSC translocation in R201. The results indicate that stem NSC translocation could be beneficial for enhancement of grain yield potential, and poor unloading into caryopsis may be the possible cause of low stem NSC translocation, poor grain filling and yield formation in R201. PMID:28848573

Optimal harvesting of a stochastic delay logistic model with Lévy jumps

NASA Astrophysics Data System (ADS)

Qiu, Hong; Deng, Wenmin

2016-10-01

The optimal harvesting problem of a stochastic time delay logistic model with Lévy jumps is considered in this article. We first show that the model has a unique global positive solution and discuss the uniform boundedness of its pth moment with harvesting. Then we prove that the system is globally attractive and asymptotically stable in distribution under our assumptions. Furthermore, we obtain the existence of the optimal harvesting effort by the ergodic method, and then we give the explicit expression of the optimal harvesting policy and maximum yield.

Expansion and Harvesting of hMSC-TERT

PubMed Central

Weber, Christian; Pohl, Sebastian; Pörtner, Ralf; Wallrapp, Christine; Kassem, Moustapha; Geigle, Peter; Czermak, Peter

2007-01-01

The expansion of human mesenchymal stem cells as suspension culture by means of spinner flasks and microcarriers, compared to the cultivation in tissue culture flasks, offers the advantage of reducing the requirements of large incubator capacities as well as reducing the handling effort during cultivation and harvesting. Nonporous microcarriers are preferable when the cells need to be kept in viable condition for further applications like tissue engineering or cell therapy. In this study, the qualification of Biosilon, Cytodex 1, Cytodex 3, RapidCell and P102-L for expansion of hMSC-TERT with an associated harvesting process using either trypsin, accutase, collagenase or a trypsin-accutase mixture was investigated. A subsequent adipogenic differentiation of harvested hMSC-TERT was performed in order to observe possible negative effects on their (adipogenic) differentiation potential as a result of the cultivation and harvesting method. The cultivated cells showed an average growth rate of 0.52 d-1. The cells cultivated on Biosilon, RapidCell and P102-L were harvested succesfully achieving high cell yield and vitalities near 100%. This was not the case for cells on Cytodex 1 and Cytodex 3. The trypsin-accutase mix was most effective. After spinner expansion and harvesting the cells were successfully differentiated to adipocytes. PMID:19662126

A shell-neutral modeling approach yields sustainable oyster harvest estimates: a retrospective analysis of the Louisiana state primary seed grounds

USGS Publications Warehouse

Soniat, Thomas M.; Klinck, John M.; Powell, Eric N.; Cooper, Nathan; Abdelguerfi, Mahdi; Hofmann, Eileen E.; Dahal, Janak; Tu, Shengru; Finigan, John; Eberline, Benjamin S.; La Peyre, Jerome F.; LaPeyre, Megan K.; Qaddoura, Fareed

2012-01-01

A numerical model is presented that defines a sustainability criterion as no net loss of shell, and calculates a sustainable harvest of seed (<75 mm) and sack or market oysters (≥75 mm). Stock assessments of the Primary State Seed Grounds conducted east of the Mississippi from 2009 to 2011 show a general trend toward decreasing abundance of sack and seed oysters. Retrospective simulations provide estimates of annual sustainable harvests. Comparisons of simulated sustainable harvests with actual harvests show a trend toward unsustainable harvests toward the end of the time series. Stock assessments combined with shell-neutral models can be used to estimate sustainable harvest and manage cultch through shell planting when actual harvest exceeds sustainable harvest. For exclusive restoration efforts (no fishing allowed), the model provides a metric for restoration success-namely, shell accretion. Oyster fisheries that remove shell versus reef restorations that promote shell accretion, although divergent in their goals, are convergent in their management; both require vigilant attention to shell budgets.

[Effects of reduced N application rate on yield and nutrient uptake and utilization in maize-soybean relay strip intercropping system].

PubMed

Yong, Tai-Wen; Liu, Xiao-Ming; Wen-Yu, Liu; Su, Ben-Ying; Song, Chun; Yang, Feng; Wang, Xiao-Chun; Yang, Wen-Yu

2014-02-01

A field experiment with three N application rates (0, 180, 240 N kg x hm(-2), representing zero, reduced and conventional N application, respectively) and three planting patterns (maize monoculture, soybean monoculture and maize-soybean relay strip intercropping) was conducted to reveal the effects of cropping patterns and N application rates on yield, nutrient uptake and nitrogen use efficiency of maize and soybean. The results showed that the grain yield, N, P and K uptake and harvest index of the intercropped maize reduced slightly compared with the monoculture maize, however these indices of the intercropped soybean increased significantly compared with the monoculture. With the increase in nitrogen fertilizer application, the excellence of relay strip intercropping was weakened in the maize-soybean intercropping system. The grain yield, economic coefficient, N, P and K uptake, harvest index, N agronomy efficiency and N uptake efficiency of maize and soybean increased significantly at the reduced nitrogen rate (180 N kg x hm(-2)), but the rate of soil N contribution declined, compared with the conventional rate of N application by local farmers (240 N kg x hm(-2)). In the reduced nitrogen rate treatment, total soil N and P contents of the maize strip reduced, whereas the total soil N, P and K contents of soybean strip and the total K content of maize strip increased compared with the zero N application treatment. With the reduced N application, the annual total grain yield, N, P and K uptake of above-ground biomass in the maize-soybean relay strip intercropping system were higher than in the monoculture, and the land equivalent ratio (LER) was 2.28. N uptake efficiency of maize in the relay strip intercropping system was 20.2% higher than in the maize monoculture, and the index of soybean was 30.5% lower than in the monoculture. The rate of soil N contribution in the relay strip intercropping system was 20.0% and 8.8% lower than in the maize and soybean

Response of Biomass Development, Essential Oil, and Composition of Plectranthus amboinicus (Lour.) Spreng. to Irrigation Frequency and Harvest Time.

PubMed

Sabra, Ali S; Astatkie, Tessema; Alataway, Abed; Mahmoud, Abeer A; Gendy, Ahmed S H; Said-Al Ahl, Hussein A H; Tkachenko, Kirill G

2018-03-01

A greenhouse experiment was conducted to study the effects of four irrigation intervals (4, 8, 12, and 16 days) and six harvests (2, 4, 6, 8, 10, and 12 months after transplanting) on biomass, essential oil content, and composition of Plectranthus amboinicus (Lour.) Spreng. Fresh weight and essential oil yield decreased with increasing irrigation interval; whereas, essential oil content was stimulated by water stress and increased as the irrigation interval increased. Fresh weight of Plectranthus amboinicus irrigated every 4 days peaked when harvested at 6 months, but essential oil content peaked when irrigated every 16 days and harvested at 2 months after transplantation. On the other hand, essential oil yield peaked when irrigated every 8 days and harvested at 6 months. Thymol, p-cymene, γ-terpinene, and β-caryophyllene were the major compounds, and they peaked at different irrigation intervals and harvest times. This study showed biomass, essential oil content, and yield as well as the major and minor constituents of Plectranthus amboinicus are influenced by irrigation interval and the timing of harvest. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

Impact of switchgrass harvest time on biomass yield and conversion

USDA-ARS?s Scientific Manuscript database

Switchgrass (Panicum virgatum L.) is a perennial grass native to much of North America being developed as a dedicated energy crop for conversion to biofuels. Breeding efforts are focused on producing high-yielding cultivars that can maintain high yield across multiple environments, including poor so...

Harvesting the Pea Genome: Association Mapping of the Pisum Single Plant Plus Collection

USDA-ARS?s Scientific Manuscript database

Yield per se is a difficult trait to improve due to the quantitative nature and low heritability of this trait. Nevertheless, yield is the most important trait for crop improvement. Development of higher yielding pea cultivars will depend on harvesting allelic diversity harbored in ex situ germpla...

LACIE: Wheat yield models for the USSR

NASA Technical Reports Server (NTRS)

Sakamoto, C. M.; Leduc, S. K.

1977-01-01

A quantitative model determining the relationship between weather conditions and wheat yield in the U.S.S.R. was studied to provide early reliable forecasts on the size of the U.S.S.R. wheat harvest. Separate models are developed for spring wheat and for winter. Differences in yield potential and responses to stress conditions and cultural improvements necessitate models for each class.

Enhancing biomass energy yield from pilot-scale high rate algal ponds with recycling.

PubMed

Park, J B K; Craggs, R J; Shilton, A N

2013-09-01

This paper investigates the effect of recycling on biomass energy yield in High Rate Algal Ponds (HRAPs). Two 8 m(3) pilot-scale HRAPs treating primary settled sewage were operated in parallel and monitored over a 2-year period. Volatile suspended solids were measured from both HRAPs and their gravity settlers to determine biomass productivity and harvest efficiency. The energy content of the biomass was also measured. Multiplying biomass productivity and harvest efficiency gives the 'harvestable biomass productivity' and multiplying this by the energy content defines the actual 'biomass energy yield'. In Year 1, algal recycling was implemented in one of the ponds (HRAPr) and improved harvestable biomass productivity by 58% compared with the control (HRAPc) without recycling (HRAPr: 9.2 g/m(2)/d; HRAPc: 5.8 g/m(2)/d). The energy content of the biomass grown in HRAPr, which was dominated by Pediastrun boryanum, was 25% higher than the control HRAPc which contained a mixed culture of 4-5 different algae (HRAPr: 21.5 kJ/g; HRAPc: 18.6 kJ/g). In Year 2, HRAPc was then seeded with the biomass harvested from the P. boryanum dominated HRAPr. This had the effect of shifting algal dominance from 89% Dictyosphaerium sp. (which is poorly-settleable) to over 90% P. boryanum in 5 months. Operation of this pond was then switched to recycling its own harvested biomass, which maintained P. boryanum dominance for the rest of Year 2. This result confirms, for the first time in the literature, that species control is possible for similarly sized co-occurring algal colonies in outdoor HRAP by algal recycling. With regard to the overall improvement in biomass energy yield, which is a critical parameter in the context of algal cultivation for biofuels, the combined improvements that recycling triggered in biomass productivity, harvest efficiency and energy content enhanced the harvested biomass energy yield by 66% (HRAPr: 195 kJ/m(2)/day; HRAPc: 118 kJ/m(2)/day). Copyright © 2013

Metamaterials-based enhanced energy harvesting: A review

NASA Astrophysics Data System (ADS)

Chen, Zhongsheng; Guo, Bin; Yang, Yongmin; Cheng, Congcong

2014-04-01

Advances in low power design open the possibility to harvest ambient energies to power directly the electronics or recharge a secondary battery. The key parameter of an energy harvesting (EH) device is its efficiency, which strongly depends on the conversion medium. To address this issue, metamaterials, artificial materials and structures with exotic properties, have been introduced for EH in recent years. They possess unique properties not easily achieved using naturally occurring materials, such as negative stiffness, mass, Poisson's ratio, and refractive index. The goal of this paper is to review the fundamentals, recent progresses and future directions in the field of metamaterials-based enhanced energy harvesting. An introduction on EH followed by the classification of potential metamaterials for EH is presented. A number of theoretical and experimental studies on metamaterials-based EH are outlined, including phononic crystals, acoustic metamaterials, and electromagnetic metamaterials. Finally, we give an outlook on future directions of metamaterials-based energy harvesting research including but not limited to active metamaterials-based EH, metamaterials-based thermal EH, and metamaterials-based multifunctional EH capabilities.

Relationships between primary production and crop yields in semi-arid and arid irrigated agro-ecosystems

NASA Astrophysics Data System (ADS)

Jaafar, H. H.; Ahmad, F. A.

2015-04-01

In semi-arid areas within the MENA region, food security problems are the main problematic imposed. Remote sensing can be a promising too early diagnose food shortages and further prevent the population from famine risks. This study is aimed at examining the possibility of forecasting yield before harvest from remotely sensed MODIS-derived Enhanced Vegetation Index (EVI), Net photosynthesis (net PSN), and Gross Primary Production (GPP) in semi-arid and arid irrigated agro-ecosystems within the conflict affected country of Syria. Relationships between summer yield and remotely sensed indices were derived and analyzed. Simple regression spatially-based models were developed to predict summer crop production. The validation of these models was tested during conflict years. A significant correlation (p<0.05) was found between summer crop yield and EVI, GPP and net PSN. Results indicate the efficiency of remotely sensed-based models in predicting summer yield, mostly for cotton yields and vegetables. Cumulative summer EVI-based model can predict summer crop yield during crisis period, with deviation less than 20% where vegetables are the major yield. This approach prompts to an early assessment of food shortages and lead to a real time management and decision making, especially in periods of crisis such as wars and drought.

Energy Harvesting Chip and the Chip Based Power Supply Development for a Wireless Sensor Network.

PubMed

Lee, Dasheng

2008-12-02

In this study, an energy harvesting chip was developed to scavenge energy from artificial light to charge a wireless sensor node. The chip core is a miniature transformer with a nano-ferrofluid magnetic core. The chip embedded transformer can convert harvested energy from its solar cell to variable voltage output for driving multiple loads. This chip system yields a simple, small, and more importantly, a battery-less power supply solution. The sensor node is equipped with multiple sensors that can be enabled by the energy harvesting power supply to collect information about the human body comfort degree. Compared with lab instruments, the nodes with temperature, humidity and photosensors driven by harvested energy had variation coefficient measurement precision of less than 6% deviation under low environmental light of 240 lux. The thermal comfort was affected by the air speed. A flow sensor equipped on the sensor node was used to detect airflow speed. Due to its high power consumption, this sensor node provided 15% less accuracy than the instruments, but it still can meet the requirement of analysis for predicted mean votes (PMV) measurement. The energy harvesting wireless sensor network (WSN) was deployed in a 24-hour convenience store to detect thermal comfort degree from the air conditioning control. During one year operation, the sensor network powered by the energy harvesting chip retained normal functions to collect the PMV index of the store. According to the one month statistics of communication status, the packet loss rate (PLR) is 2.3%, which is as good as the presented results of those WSNs powered by battery. Referring to the electric power records, almost 54% energy can be saved by the feedback control of an energy harvesting sensor network. These results illustrate that, scavenging energy not only creates a reliable power source for electronic devices, such as wireless sensor nodes, but can also be an energy source by building an energy efficient

Energy Harvesting Chip and the Chip Based Power Supply Development for a Wireless Sensor Network

PubMed Central

Lee, Dasheng

2008-01-01

In this study, an energy harvesting chip was developed to scavenge energy from artificial light to charge a wireless sensor node. The chip core is a miniature transformer with a nano-ferrofluid magnetic core. The chip embedded transformer can convert harvested energy from its solar cell to variable voltage output for driving multiple loads. This chip system yields a simple, small, and more importantly, a battery-less power supply solution. The sensor node is equipped with multiple sensors that can be enabled by the energy harvesting power supply to collect information about the human body comfort degree. Compared with lab instruments, the nodes with temperature, humidity and photosensors driven by harvested energy had variation coefficient measurement precision of less than 6% deviation under low environmental light of 240 lux. The thermal comfort was affected by the air speed. A flow sensor equipped on the sensor node was used to detect airflow speed. Due to its high power consumption, this sensor node provided 15% less accuracy than the instruments, but it still can meet the requirement of analysis for predicted mean votes (PMV) measurement. The energy harvesting wireless sensor network (WSN) was deployed in a 24-hour convenience store to detect thermal comfort degree from the air conditioning control. During one year operation, the sensor network powered by the energy harvesting chip retained normal functions to collect the PMV index of the store. According to the one month statistics of communication status, the packet loss rate (PLR) is 2.3%, which is as good as the presented results of those WSNs powered by battery. Referring to the electric power records, almost 54% energy can be saved by the feedback control of an energy harvesting sensor network. These results illustrate that, scavenging energy not only creates a reliable power source for electronic devices, such as wireless sensor nodes, but can also be an energy source by building an energy efficient

Anaerobic digestion of spring and winter wheat: Comparison of net energy yields.

PubMed

Rincón, Bárbara; Heaven, Sonia; Salter, Andrew M; Banks, Charles J

2016-10-14

Anaerobic digestion of wheat was investigated under batch conditions. The article compares the potential net energy yield between a winter wheat (sown in the autumn) and a spring wheat (sown in the spring) grown in the same year and harvested at the same growth stage in the same farm. The spring wheat had a slightly higher biochemical methane potential and required lower energy inputs in cultivation, but produced a lower dry biomass yield per hectare, which resulted in winter wheat providing the best overall net energy yield. The difference was small; both varieties gave a good net energy yield. Spring sowing may also offer the opportunity for growing an additional over-winter catch crop for spring harvest, thus increasing the overall biomass yield per hectare, with both crops being potential digester feedstocks.

Yield of illicit indoor cannabis cultivation in the Netherlands.

PubMed

Toonen, Marcel; Ribot, Simon; Thissen, Jac

2006-09-01

To obtain a reliable estimation on the yield of illicit indoor cannabis cultivation in The Netherlands, cannabis plants confiscated by the police were used to determine the yield of dried female flower buds. The developmental stage of flower buds of the seized plants was described on a scale from 1 to 10 where the value of 10 indicates a fully developed flower bud ready for harvesting. Using eight additional characteristics describing the grow room and cultivation parameters, regression analysis with subset selection was carried out to develop two models for the yield of indoor cannabis cultivation. The median Dutch illicit grow room consists of 259 cannabis plants, has a plant density of 15 plants/m(2), and 510 W of growth lamps per m(2). For the median Dutch grow room, the predicted yield of female flower buds at the harvestable developmental stage (stage 10) was 33.7 g/plant or 505 g/m(2).

Computing wheat nitrogen requirements from grain yield and protein maps

USDA-ARS?s Scientific Manuscript database

Optical protein sensors and mass-flow yield monitors provide the opportunity to continuously measure grain quality and quantity during harvesting. This chapter illustrates how yield monitor and grain protein measurements may provide useful postharvest information for evaluating water or nitrogen (N)...

Comparative assessment of smallholder sustainability using an agricultural sustainability framework and a yield based index insurance: A case study

NASA Astrophysics Data System (ADS)

Moshtaghi, Mehrdad; Adla, Soham; Pande, Saket; Disse, Markus; Savenije, Hubert

2017-04-01

The concept of sustainability is central to smallholder agriculture as subsistence farming is constantly impacted by livelihood insecurity and is constrained by access to capital, water technology and alternative employment opportunities. This study compares two approaches which aim at quantifying smallholder sustainability but differ in their underlying principles, methodologies for assessment and reporting, and applications. The yield index based insurance can protect the smallholder agriculture and help it to more economic sustainability because the income of smallholder depends on selling crops and this insurance scheme is based on crop yields. In this research, the trigger of this insurance sets on the basis of yields in previous years. The crop yields are calculated every year through socio-hydrology modeling and smallholder can get indemnity when crop yields are lower than average of previous five years (a crop failure). The FAO Sustainability Assessment of Food and Agriculture (SAFA) is an inclusive and comprehensive framework for sustainability assessment in the food and agricultural sector. It follows the UN definition of the 4 dimensions of sustainability (good governance, environmental integrity, economic resilience and social well-being) and includes 21 themes and 58 sub-themes with a multi-indicator approach. The direct sustainability corresponding to the FAO SAFA economic resilience dimension is compared with the indirect notion of sustainability derived from the yield based index insurance. A semi-synthetic comparison is conducted to understand the differences in the underlying principles, methodologies and application of the two approaches. Both approaches are applied to data from smallholder regions of Marathwada in Maharashtra (India) which experienced a severe rise in farmer suicides in the 2000s which has been attributed to a combination of socio-hydrological factors.

Silvicultural Prescriptions Influence the Proportion of High-Quality Hardwood Butt Logs Harvested over a Half-Century of Management

Treesearch

John P. Brown; Melissa A. Thomas-Van Gundy; Thomas M. Schuler; Janice K. Wiedenbeck

2018-01-01

A long-term study on the Fernow Experimental Forest (FEF) in West Virginia provided an opportunity to test for differences in the timber quality of trees harvested from three silvicultural practices (HarvestType): diameter-limit, patch cutting, and single-tree selection. The effects of HarvestType and site index (SI) over time on the harvested proportion of trees with...

Biological Implications in Cassava for the Production of Amylose-Free Starch: Impact on Root Yield and Related Traits

PubMed Central

Karlström, Amanda; Calle, Fernando; Salazar, Sandra; Morante, Nelson; Dufour, Dominique; Ceballos, Hernán

2016-01-01

Cassava (Manihot esculenta, Crantz) is an important food security crop, but it is becoming an important raw material for different industrial applications. Cassava is the second most important source of starch worldwide. Novel starch properties are of interest to the starch industry, and one them is the recently identified amylose-free (waxy) cassava starch. Waxy mutants have been found in different crops and have been often associated with a yield penalty. There are ongoing efforts to develop commercial cassava varieties with amylose-free starch. However, little information is available regarding the biological and agronomic implications of starch mutations in cassava, nor in other root and tuber crops. In this study, siblings from eight full-sib families, segregating for the waxy trait, were used to determine if the mutation has implications for yield, dry matter content (DMC) and harvest index in cassava. A total of 87 waxy and 87 wild-type starch genotypes from the eight families were used in the study. The only significant effect of starch type was on DMC (p < 0.01), with waxy clones having a 0.8% lower content than their wild type counterparts. There was no effect of starch type on fresh root yield (FRY), adjusted FRY and harvest index. It is not clear if lower DMC is a pleiotropic effect of the waxy starch mutation or else the result of linked genes introgressed along with the mutation. It is expected that commercial waxy cassava varieties will have competitive FRYs but special efforts will be required to attain adequate DMCs. This study contributes to the limited knowledge available of the impact of starch mutations on the agronomic performance of root and tuber crops. PMID:27242813

Variations in Volatile Oil Yield and Composition of "Xin-yi" (Magnolia biondii Pamp. Flower Buds) at Different Growth Stages.

PubMed

Hu, Mingli; Bai, Mei; Ye, Wei; Wang, Yaling; Wu, Hong

2018-06-01

Dried flower buds of Magnolia biondii Pamp. are the main ingredient in "Xin-yi" in China, and the volatile oils of M. biondii flower buds are the principal medicinal component. Gas chromatographymass spectrometry (GC-MS) and microscopic techniques were employed to detect the volatile yields of M. biondii flowers at various growth stages. The volatile oil yields of M. biondii flowers differed significantly at different growth stages and were closely related to flower dry weight, oil cell density and degree of oil accumulation. In February 2016, flower buds had the highest dry weight, the maximum percentage of oil cells at the oil saturation stage and the highest density of oil cells, which coincided with the highest oil yield. In March 2016, flower buds had a lower dry weight, a higher percentage of oil cells at the oil-degrading stage and the lowest oil cell density, resulting in decreased oil yields. The total amounts of the major medicinal components in the M. biondii flower also showed regular changes at different growth stages. In January and February of 2016, M. biondii flowers had a higher dry weight, volatile oil yield and total content of medicinal ingredients, which was the best time for harvesting high-quality medicinal components. Our study reveals that volatile oil content and chemical composition are closely related to the growth stage of M. biondii flower buds. The results provide a scientific morphology and composition index for evaluating the medicinal value and harvesting of high-quality M. biondii medicinal herbs.

Using remote sensing satellite data and artificial neural network for prediction of potato yield in Bangladesh

NASA Astrophysics Data System (ADS)

Akhand, Kawsar; Nizamuddin, Mohammad; Roytman, Leonid; Kogan, Felix

2016-09-01

Potato is one of the staple foods and cash crops in Bangladesh. It is widely cultivated in all of the districts and ranks second after rice in production. Bangladesh is the fourth largest potato producer in Asia and is among the world's top 15 potato producing countries. The weather condition for potato cultivation is favorable during the sowing, growing and harvesting period. It is a winter crop and is cultivated during the period of November to March. Bangladesh is mainly an agricultural based country with respect to agriculture's contribution to GDP, employment and consumption. Potato is a prominent crop in consideration of production, its internal demand and economic value. Bangladesh has a big economic activities related to potato cultivation and marketing, especially the economic relations among farmers, traders, stockers and cold storage owners. Potato yield prediction before harvest is an important issue for the Government and the stakeholders in managing and controlling the potato market. Advanced very high resolution radiometer (AVHRR) based satellite data product vegetation health indices VCI (vegetation condition index) and TCI (temperature condition index) are used as predictors for early prediction. Artificial neural network (ANN) is used to develop a prediction model. The simulated result from this model is encouraging and the error of prediction is less than 10%.

A data discovery index for the social sciences

PubMed Central

Krämer, Thomas; Klas, Claus-Peter; Hausstein, Brigitte

2018-01-01

This paper describes a novel search index for social and economic research data, one that enables users to search up-to-date references for data holdings in these disciplines. The index can be used for comparative analysis of publication of datasets in different areas of social science. The core of the index is the da|ra registration agency’s database for social and economic data, which contains high-quality searchable metadata from registered data publishers. Research data’s metadata records are harvested from data providers around the world and included in the index. In this paper, we describe the currently available indices on social science datasets and their shortcomings. Next, we describe the motivation behind and the purpose for the data discovery index as a dedicated and curated platform for finding social science research data and gesisDataSearch, its user interface. Further, we explain the harvesting, filtering and indexing procedure and give usage instructions for the dataset index. Lastly, we show that the index is currently the most comprehensive and most accessible collection of social science data descriptions available. PMID:29633988

Short-term alteration of nitrogen supply prior to harvest affects quality in hydroponic-cultivated spinach (Spinacia oleracea).

PubMed

Lin, Xian Yong; Liu, Xiao Xia; Zhang, Ying Peng; Zhou, Yuan Qing; Hu, Yan; Chen, Qiu Hui; Zhang, Yong Song; Jin, Chong Wei

2014-03-30

Quality-associated problems, such as excessive in planta accumulation of oxalate, often arise in soillessly cultivated spinach (Spinacia oleracea). Maintaining a higher level of ammonium (NH₄⁺) compared to nitrate (NO₃⁻) during the growth period can effectively decrease the oxalate content in hydroponically cultivated vegetables. However, long-term exposure to high concentrations of NH₄⁺ induces toxicity in plants, and thus decreases the biomass production. Short-term application of NH₄⁺ before harvesting in soilless cultivation may provide an alternative strategy to decrease oxalate accumulation in spinach, and minimise the yield reduction caused by NH₄⁺ toxicity. The plants were pre-cultured in 8 mmol L⁻¹ NO₃⁻ nutrient solution. Next, 6 days before harvest, the plants were transferred to a nutrient solution containing 4 mmol L⁻¹ NO₃⁻ and 4 mmol L⁻¹ NH₄⁺. This new mix clearly reduced oxalate accumulation, increased levels of several antioxidant compounds, and enhanced antioxidant capacity in the edible parts of spinach plants, but it did not affect biomass production. However, when the 8 mmol L⁻¹ NO₃⁻ was shifted to either nitrogen-free, 4 mmol L⁻¹ NH₄⁺ or 8 mmol L⁻¹ NH₄⁺ treatments, although some of the quality indexes were improved, yields were significantly reduced. Short-term alteration of nitrogen supply prior to harvest significantly affects quality and biomass of spinach plants, and we strongly recommend to simultaneously use NO₃⁻ and NH₄⁺ in hydroponic cultivation, which improves vegetable quality without decreasing biomass production. © 2013 Society of Chemical Industry.

The Effect of Plant Cultivar, Growth Media, Harvest Method and Post Harvest Treatment on the Microbiology of Edible Crops

NASA Technical Reports Server (NTRS)

Hummerick, Mary P.; Gates, Justin R.; Nguyen, Bao-Thang; Massa, Gioia D.; Wheeler, Raymond M.

2011-01-01

Systems for the growth of crops in closed environments are being developed and tested for potential use in space applications to provide a source of fresh food. Plant growth conditions, growth media composition and harvest methods can have an effect on the microbial population of the plant, and therefore should be considered along with the optimization of plant growth and harvest yields to ensure a safe and palatable food crop. This work examines the effect of plant cultivar, growth media, and harvest method on plant microbial populations. Twelve varieties of leafy greens and herbs were grown on a mixture of Fafard #2 and Arcillite in the pillow root containment system currently being considered for the VEGGIE plant growth unit developed by Orbitec. In addition, ,Sierra and Outredgeous lettuce varieties were grown in three different mixtures (Fafard #2, Ardllite, and Perlite/Vermiculite). The plants were analyzed for microbial density. Two harvest methods, "cut and come again" (CACA) and terminal harvest were also compared. In one set ofexpe'riments red leaf lettuce and mizuna were grown in pots in a Biomass Production System for education. Plants were harvested every two weeks by either method. Another set of experiments was performed using the rooting pillows to grow 5 varieties of leafy greens and cut harvesting at different intervals. Radishes were harvested and replanted at two-week intervals. Results indicate up to a 3 IOglO difference in microbial counts between some varieties of plants. Rooting medium resulted in an approximately 2 IOglO lower count in the lettuce grown in arscillite then those grown in the other mixtures. Harvest method and frequency had less impact on microbial counts only showing a significant increase in one variety of plant. Post harvest methods to decrease the bacterial counts on edible crops were investigated in these and other experiments. The effectiveness of PRO-SAN and UV-C radiation is compared.

Ecohydrology of agroecosystems: probabilistic description of yield reduction risk under limited water availability

NASA Astrophysics Data System (ADS)

Vico, Giulia; Porporato, Amilcare

2013-04-01

Supplemental irrigation represents one of the main strategies to mitigate the effects of climate variability and stabilize yields. Irrigated agriculture currently provides 40% of food production and its relevance is expected to further increase in the near future, in face of the projected alterations of rainfall patterns and increase in food, fiber, and biofuel demand. Because of the significant investments and water requirements involved in irrigation, strategic choices are needed to preserve productivity and profitability, while maintaining a sustainable water management - a nontrivial task given the unpredictability of the rainfall forcing. To facilitate decision making under uncertainty, a widely applicable probabilistic framework is proposed. The occurrence of rainfall events and irrigation applications are linked probabilistically to crop development during the growing season and yields at harvest. Based on these linkages, the probability density function of yields and corresponding probability density function of required irrigation volumes, as well as the probability density function of yields under the most common case of limited water availability are obtained analytically, as a function of irrigation strategy, climate, soil and crop parameters. The full probabilistic description of the frequency of occurrence of yields and water requirements is a crucial tool for decision making under uncertainty, e.g., via expected utility analysis. Furthermore, the knowledge of the probability density function of yield allows us to quantify the yield reduction hydrologic risk. Two risk indices are defined and quantified: the long-term risk index, suitable for long-term irrigation strategy assessment and investment planning, and the real-time risk index, providing a rigorous probabilistic quantification of the emergence of drought conditions during a single growing season in an agricultural setting. Our approach employs relatively few parameters and is thus easily and

Harvesting of freshwater microalgae biomass by Scenedesmus sp. as bioflocculant

NASA Astrophysics Data System (ADS)

Rinanti, A.; Purwadi, R.

2018-01-01

This study is particularly expected to provide information on the diversity of microalgae as the flocculant agent that gives the highest biomass yield. Bioflocculation was done by using one of the flocculating microalgae i.e. Scenedesmus obliquus to concentrate on non-flocculating microalgae Chlorella vulgaris. The freshwater microalgae S. obliquus tested it ability to harvest other non-flocculating microalgae, increased sedimentation rate in the flocculation process and increased biomass yield. The flocculation of biomass microalgae with chemical flocculant as comparison was done by adding alum (K2SO4·Al2 (SO4)3·24H2O). The addition of alum (K2SO4·Al2 (SO4)3·24H2O) as flocculant at pH 11 and S. obliquus sp. as bioflocculant caused significant alteration of nutrition of microalgae. Overall, the essential content produced by flocculation method with addition of alum or with bioflocculation (%, mg/100 mg dry weight) are lipid 31,64; 38,69, protein 30,79; 38.50%, and chlorophyll 0.6253; 0.8420). Harvesting with bioflocculation methods conducted at the end of the cultivation period increase the amount of biomass significantly and can accelerate the settling time of biomass. Harvesting microalgae cells by bioflocculation method becomes an economically competitive harvesting method compared to alum as a chemical flocculant because of the cheaper cost of flocculant, not toxic so it does not require further water treatment after harvesting due to the use of alum as chemical flocculants.

Can We Sustainably Harvest Ivory?

PubMed

Lusseau, David; Lee, Phyllis C

2016-11-07

Despite the 1989 ivory trade ban, elephants continue to be killed to harvest their tusks for ivory. Since 2008, this poaching has increased to unprecedented levels driven by consumer demand for ivory products. CITES is now considering the development of a legal ivory trade [1, 2]. The proposal relies on three assumptions: (1) harvest regulation will cease all illegal activities, (2) defined sustainable quotas can be enforced, and (3) we can define meaningful sustainable quotas that come close to the current demand. We know that regulation of harvest does not stop illegal takes. Despite whaling regulation after World War II, illegal whaling continued for decades [3]. The introduction of wolf culls in the US actually increased poaching activities [4], and one-off ivory sales in 1999 and 2008 did nothing to halt elephant poaching. Governance issues over the ivory supply chains, including stockpiling, make enforcing quotas challenging, if not impossible [5, 6]. We have not yet adequately assessed what could be a sustainable ivory yield. To do so, we develop a compartmental model composed of a two-sex age-structured demographic model and an ivory production and harvest model. We applied several offtake and quota strategies to define how much ivory could be sustainably harvested. We found that the sustainability space is very small. Only 100 to 150 kg of ivory could be removed from a reference population of 1,360 elephants, levels well below the current demand. Our study shows that lifting the ivory ban will not address the current poaching challenge. We should instead focus on reducing consumer demand. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modeling and simulating two cut-to-length harvesting systems in central Appalachian hardwoods

Treesearch

Jingxin Wang; Chris B. LeDoux; Yaoxiang Li

2003-01-01

The production rates and costs of two cut-to-length harvesting systems was simulated using a modular ground-based simulation model and stand yield data from fully stocked, second growth even aged central Appalachian hardwood forests. The two harvesters simulated were a modified John Deere 988 tracked excavator with a model RP 1600 single grip sawhead and an excavator...

Facile Growth of High-Yield Gold Nanobipyramids Induced by Chloroplatinic Acid for High Refractive Index Sensing Properties.

PubMed

Fang, Caihong; Zhao, Guili; Xiao, Yanling; Zhao, Jun; Zhang, Zijun; Geng, Baoyou

2016-11-14

Au nanobipyramids (NBPs) have attracted great attention because of their unique localized surface plasmon resonance properties. However, the current growth methods always have low yield or suffer tedious process. Developing new ways to direct synthesis of high-yield Au NBPs using common agents is therefore desirable. Here, we employed chloroplatinic acid as the key shape-directing agent for the first time to grow Au NBPs using a modified seed-mediated method at room temperature. H 2 PtCl 6 was added both during the seed preparation and in growth solution. Metallic Pt, reduced from chloroplatinic acid, will deposit on the surface of the seed nanoparticles and the Au nanocrystals and thus plays a critical role for the formation of Au NBPs. Additionally, the reductant, precursor, and surfactant are all cheap and commonly used. Furthermore, the Au NBPs offer narrow size distribution, two sharp tips, and a shared basis. Au NBPs therefore show much higher refractive index sensitivities than that of the Au nanorods. The refractive index sensitivities and lager figure of merit values of Au NBPs exhibit an increase of 63% and 321% respectively compared to the corresponding values of Au nanorod sample.

From lab to full-scale ultrafiltration in microalgae harvesting

NASA Astrophysics Data System (ADS)

Wenten, I. G.; Steven, S.; Dwiputra, A.; Khoiruddin; Hakim, A. N.

2017-07-01

Ponding system is generally used for microalgae cultivation. However, selection of appropriate technology for the harvesting process is challenging due to the low cell density of cultivated microalgae from the ponding system and the large volume of water to be handled. One of the promising technologies for microalgae harvesting is ultrafiltration (UF). In this study, the performance of UF during harvesting of microalgae in a lab- and a full-scale test is investigated. The performances of both scales are compared and analyzed to provide an understanding of several aspects which affect the yield produced from lab and actual conditions. Furthermore, a unique self-standing non-modular UF is introduced in the full-scale test. The non-modular UF exhibits several advantages, such as simple piping and connection, single pump for filtration and backwashing, and smaller footprint. With those advantages, the non-modular UF could be a promising technology for microalgae harvesting in industrial-scale.

An optimal staggered harvesting strategy for herbaceous biomass energy crops

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhat, M.G.; English, B.C.

1993-12-31

Biofuel research over the past two decades indicates lignocellulosic crops are a reliable source of feedstock for alternative energy. However, under the current technology of producing, harvesting and converting biomass crops, the cost of biofuel is not competitive with conventional biofuel. Cost of harvesting biomass feedstock is a single largest component of feedstock cost so there is a cost advantage in designing a biomass harvesting system. Traditional farmer-initiated harvesting operation causes over investment. This study develops a least-cost, time-distributed (staggered) harvesting system for example switch grass, that calls for an effective coordination between farmers, processing plant and a single third-partymore » custom harvester. A linear programming model explicitly accounts for the trade-off between yield loss and benefit of reduced machinery overhead cost, associated with the staggered harvesting system. Total cost of producing and harvesting switch grass will decline by 17.94 percent from conventional non-staggered to proposed staggered harvesting strategy. Harvesting machinery cost alone experiences a significant reduction of 39.68 percent from moving from former to latter. The net return to farmers is estimated to increase by 160.40 percent. Per tonne and per hectare costs of feedstock production will decline by 17.94 percent and 24.78 percent, respectively. These results clearly lend support to the view that the traditional system of single period harvesting calls for over investment on agricultural machinery which escalates the feedstock cost. This social loss to the society in the form of escalated harvesting cost can be avoided if there is a proper coordination among farmers, processing plant and custom harvesters as to when and how biomass crop needs to be planted and harvested. Such an institutional arrangement benefits producers, processing plant and, in turn, end users of biofuels.« less

Harvested area gaps in China between 1981 and 2010: effects of climatic and land management factors

NASA Astrophysics Data System (ADS)

Yu, Qiangyi; van Vliet, Jasper; Verburg, Peter H.; You, Liangzhi; Yang, Peng; Wu, Wenbin

2018-04-01

Previous analyses have shown that cropland in China is intensifying, leading to an increase in crop production. However, these output measures leave the potential for further intensification largely unassessed. This study uses the harvested area gap (HAG), which expresses the amount of harvested area that can be gained if all existing cropland is harvested as frequently as possible, according to their potential limit for multi-cropping. Specifically, we calculate the HAG and changes in the HAG in China between 1981 and 2010. We further assess how climatic and land management factors affect these changes. We find that in China the HAG decreases between the 1980s and the 1990s, and subsequently increases between the 1990s and the 2000s, resulting in a small net increase for the entire study period. The initial decrease in the HAG is the result of an increase in the average multi-cropping index throughout the country, which is larger than the increase in the potential multi-cropping index as a result of the changed climatic factors. The subsequent increase in the HAG is the result of a decrease in average multi-cropping index throughout the country, in combination with a stagnant potential. Despite the overall increase in harvested area in China, many regions, e.g. Northeast and Lower Yangtze, are characterized by an increased HAG, indicating their potential for further increasing the multi-cropping index. The study demonstrates the application of the HAG as a method to identify areas where the harvested area can increase to increase crop production, which is currently underexplored in scientific literature.

Magnetic circuit modifications in resonant vibration harvesters

NASA Astrophysics Data System (ADS)

Szabo, Zoltan; Fiala, Pavel; Dohnal, Premysl

2018-01-01

The paper discusses the conclusions obtained from a research centered on a vibration-powered milli- or micro generator (MG) operating as a harvester to yield the maximum amount of energy transferred by the vibration of an independent system. The investigation expands on the results proposed within papers that theoretically define the properties characterizing the basic configurations of a generator based on applied Faraday's law of induction. We compared two basic principles of circuit closing in a magnetic circuit that, fully or partially, utilizes a ferromagnetic material, and a large number of generator design solutions were examined and tested. In the given context, the article brings a compact survey of the rules facilitating energy transformation and the designing of harvesters.

Ozone Exposure Response for U.S. Soybean Cultivars: Linear Reductions in Photosynthetic Potential, Biomass, and Yield1[W][OA

PubMed Central

Betzelberger, Amy M.; Yendrek, Craig R.; Sun, Jindong; Leisner, Courtney P.; Nelson, Randall L.; Ort, Donald R.; Ainsworth, Elizabeth A.

2012-01-01

Current background ozone (O3) concentrations over the northern hemisphere’s midlatitudes are high enough to damage crops and are projected to increase. Soybean (Glycine max) is particularly sensitive to O3; therefore, establishing an O3 exposure threshold for damage is critical to understanding the current and future impact of this pollutant. This study aims to determine the exposure response of soybean to elevated tropospheric O3 by measuring the agronomic, biochemical, and physiological responses of seven soybean genotypes to nine O3 concentrations (38–120 nL L−1) within a fully open-air agricultural field location across 2 years. All genotypes responded similarly, with season-long exposure to O3 causing a linear increase in antioxidant capacity while reducing leaf area, light absorption, specific leaf mass, primary metabolites, seed yield, and harvest index. Across two seasons with different temperature and rainfall patterns, there was a robust linear yield decrease of 37 to 39 kg ha−1 per nL L−1 cumulative O3 exposure over 40 nL L−1. The existence of immediate effects of O3 on photosynthesis, stomatal conductance, and photosynthetic transcript abundance before and after the initiation and termination of O3 fumigation were concurrently assessed, and there was no evidence to support an instantaneous photosynthetic response. The ability of the soybean canopy to intercept radiation, the efficiency of photosynthesis, and the harvest index were all negatively impacted by O3, suggesting that there are multiple targets for improving soybean responses to this damaging air pollutant. PMID:23037504

Efficiency of Energy Harvesting in Ni-Mn-Ga Shape Memory Alloys

NASA Astrophysics Data System (ADS)

Lindquist, Paul; Hobza, Tony; Patrick, Charles; Müllner, Peter

2018-03-01

Many researchers have reported on the voltage and power generated while energy harvesting using Ni-Mn-Ga shape memory alloys; few researchers report on the power conversion efficiency of energy harvesting. We measured the magneto-mechanical behavior and energy harvesting of Ni-Mn-Ga shape memory alloys to quantify the efficiency of energy harvesting using the inverse magneto-plastic effect. At low frequencies, less than 150 Hz, the power conversion efficiency is less than 0.1%. Power conversion efficiency increases with (i) increasing actuation frequency, (ii) increasing actuation stroke, and (iii) decreasing twinning stress. Extrapolating the results of low-frequency experiments to the kHz actuation regime yields a power conversion factor of about 20% for 3 kHz actuation frequency, 7% actuation strain, and 0.05 MPa twinning stress.

Yield estimation of corn based on multitemporal LANDSAT-TM data as input for an agrometeorological model

NASA Astrophysics Data System (ADS)

Bach, Heike

1998-07-01

In order to test remote sensing data with advanced yield formation models for accuracy and timeliness of yield estimation of corn, a project was conducted for the State Ministry for Rural Environment, Food, and Forestry of Baden-Württemberg (Germany). This project was carried out during the course of the `Special Yield Estimation', a regular procedure conducted for the European Union, to more accurately estimate agricultural yield. The methodology employed uses field-based plant parameter estimation from atmospherically corrected multitemporal/multispectral LANDSAT-TM data. An agrometeorological plant-production-model is used for yield prediction. Based solely on four LANDSAT-derived estimates (between May and August) and daily meteorological data, the grain yield of corn fields was determined for 1995. The modelled yields were compared with results gathered independently within the Special Yield Estimation for 23 test fields in the upper Rhine valley. The agreement between LANDSAT-based estimates (six weeks before harvest) and Special Yield Estimation (at harvest) shows a relative error of 2.3%. The comparison of the results for single fields shows that six weeks before harvest, the grain yield of corn was estimated with a mean relative accuracy of 13% using satellite information. The presented methodology can be transferred to other crops and geographical regions. For future applications hyperspectral sensors show great potential to further enhance the results for yield prediction with remote sensing.

An ecosystem-based assessment of hairtail ( Trichiurus lepturus) harvested by multi-gears and management implications in Korean waters

NASA Astrophysics Data System (ADS)

Kang, Hee Joong; Zhang, Chang Ik; Lee, Eun Ji; Seo, Young Il

2015-06-01

Hairtail ( Trichiurus lepturus) has been traditionally harvested by multi-gear types in the Yellow Sea and the East China Sea, except for the East Sea (Sea of Japan) in Korean waters. Six different fishery types such as offshore stownet fishery, offshore longline fishery, large pair-trawl fishery, large purse seine fishery, large otter trawl fishery and offshore angling fishery target to harvest the hairtail stock accounting for about 90% of the total annual catch. We attempted to develop an ecosystem-based fisheries assessment approach, which determines the optimal allocation of catch quotas and fishing efforts for major fisheries. We conducted standardization of fishing effort for six types of hairtail fisheries using a general linear model (GLM), and then estimated maximum sustainable yield (MSY) and maximum economic yield (MEY). Estimated MSY and MEY for the hairtail stock were estimated as 100,151 mt and 97,485 mt, respectively. In addition, we carried out an ecosystem-based risk analysis to obtain species risk index (SRI), which was applied to adjusting the optimal proportion of fishing effort for six hairtail fisheries as a penalty or an incentive. As a result, fishing effort ratios were adjusted by SRI for the six fisheries types. Also, the total allowable catch (TAC) was estimated as 97,485 mt and the maximum net profit at TAC by the hairtail fisheries was estimated as 778 billion won (USD 765 million).

Yield, pollination aspects and kernel qualities of almond (Prunus amygdalus Batsch) selections trialed in the Southern San Joaquin Valley

USDA-ARS?s Scientific Manuscript database

A field trial was established in the Southern San Joaquin Valley to determine yield potential for nine almond selections grown under commercial conditions. Kernel yields were first quantified in 2008, at the end of the third growing season, and continued through the 2010 harvest. Harvested tonnage...

Colostrum immunoglobulin G concentration of multiparous Jersey cows at first and second milking is associated with parity, colostrum yield, and time of first milking, and can be estimated with Brix refractometry.

PubMed

Silva-Del-Río, N; Rolle, D; García-Muñoz, A; Rodríguez-Jiménez, S; Valldecabres, A; Lago, A; Pandey, P

2017-07-01

The objective of this study was to evaluate colostrum IgG concentration harvested at first and second milking from multiparous Jersey cows, the dam's lactation number, colostrum yield, and time of first milking. In addition, we validated the use of a Brix refractometer to estimate IgG concentration in colostrum from multiparous Jersey cows using radial immunodiffusion as the reference method. Colostrum samples and total weight of colostrum harvested at first (n = 134) and second (n = 68) milking were collected from 134 multiparous Jersey cows housed in a California herd. Fresh colostrum samples were analyzed for IgG concentration with Brix refractometry and frozen samples by radial immunodiffusion. A total of 90.4 and 42.7% of the samples from first and second milking met industry standards of quality for IgG concentration (>50 g/L). Second and third lactation cows had similar colostrum IgG concentration but lower than cows on their fourth and greater lactation. At second milking, 56.4% of cows on their fourth or greater lactation had colostrum IgG concentrations >50 g/L. When colostrum yield increased from low (<3 kg), medium (3 to 6 kg), to high (>6 kg), IgG concentration decreased. Higher IgG concentration was observed on colostrum harvested at <6 h (short) versus 6 to 11 h (medium) after calving. However, IgG concentration in colostrum harvested after 11 h (long) was similar to that harvested at short and medium time. Readings of %Brix were highly correlated with IgG at first (r = 0.81) and second (r = 0.77) milking. The best Brix threshold to identify colostrum from first milking with >50 IgG g/L was 20.9% based on logit equations with Youden's index criterion and 18.0% based on accuracy criterion. For colostrum harvested at second milking, similar Brix thresholds were obtained, 19.2 and 19.0%, regardless of whether Youden's index or accuracy was used as the selection criterion. Our results indicate that the dam's lactation number, colostrum yield, and time of

Agronomic impacts of production scale harvesting of corn stover for cellulosic ethanol production in Central Iowa

NASA Astrophysics Data System (ADS)

Schau, Dustin

This thesis investigates the impacts of corn stover harvest in Central Iowa with regards to nutrient removal, grain yield impacts and soil tilth. Focusing on phosphorus and potassium removal due to production of large, square bales of corn stover, 3.7 lb P2O5 and 18.7 lb K 2O per ton of corn stover were removed in 2011. P2O 5 removal remained statistically the same in 2012, but K2O decreased to 15.1 lb per ton of corn stover. Grain cart data showed no statistical difference in grain yield between harvest treatments, but yield monitor data showed a 3 - 17 bu/ac increase in 2012 and hand samples showed a 4 - 21 bu/ac increase in 2013. Corn stover residue levels decreased below 30% coverage when corn stover was harvested the previous fall and conventional tillage methods were used, but incorporating reduced tillage practices following corn stover harvest increased residue levels back up to 30% coverage. Corn emergence rates increased by at least 2,470 more plants per acre within the first three days of spiking, but final populations between harvest and nonharvest corn stover treatments were the same. Inorganic soil nitrogen in the form of ammonium and nitrate were not directly impacted by corn stover harvest, but it is hypothesized that weather patterns had a greater impact on nitrogen availability. Lastly, soil organic matter did not statistically change from 2011 to 2013 due to corn stover removal, even when analyzed within single soil types.

Yield and utilization of hardwood fiber grown on short rotations. [Platanus occidentalis, Liquidambar styraciflua, Liriodendron tulipifera

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steinbeck, K.; Brown, C.L.

1976-01-01

Plantations of broad-leaved tree species harvested in cycles of less than 10 years can help meet man's increasing cellulose and energy needs. A system of growing hardwoods like an agricultural row crop, harvested with equipment equivalent to corn silage cutters and using the ensuing sprout growth as the next crop, was conceived by foresters in Georgia in 1965. Research has focused on the tree species, sites, and cultural practices suited for this concept as well as the biomass yields and the utility of the fiber that was produced. About 70 hectares of American sycamore (Platanus occidentalis L.), sweetgum (Liquidambar styracifluamore » L.), and yellow poplar (Liriodendron tulipifera L.) test plantings have been established in the Piedmont and Coastal Plain regions of Georgia. These species, when given proper care, can be grown successfully on many sites previously deemed unsuitable for hardwood growth. Stumps will resprout throughout the year, ensuring a continuous flow of raw material to the user. The biomass yields from hardwood fields vary with species, site, cultural practices, and rotation age. Fresh weight yields of unfoliated sycamore sprouts grown on an upland site varied from 14.3 tons/ha/yr when harvested annually to 21.8 tons/ha/yr with harvest at age four. When sprouts were harvested every two years, 46 kg/ha/2 yrs of nitrogen, 35 kg calcium, 22 kg potassium, and 6 kg phosphorus were removed in the harvested material. Juvenile American sycamore stump sprouts have been successfully converted into corrugating medium, particleboard, fiberboard, hardboard, and newsprint. It can be cooked by the Kraft and NSSC processes. One-, two-, and four-year-old sycamore sprouts presented no unusual problems in the Kraft process, and yields ranged from 45 to 57 percent with an average yield of 52 percent. Cooking times were relatively short.« less

Acquiring geographical data with web harvesting

NASA Astrophysics Data System (ADS)

Dramowicz, K.

2016-04-01

Many websites contain very attractive and up to date geographical information. This information can be extracted, stored, analyzed and mapped using web harvesting techniques. Poorly organized data from websites are transformed with web harvesting into a more structured format, which can be stored in a database and analyzed. Almost 25% of web traffic is related to web harvesting, mostly while using search engines. This paper presents how to harvest geographic information from web documents using the free tool called the Beautiful Soup, one of the most commonly used Python libraries for pulling data from HTML and XML files. It is a relatively easy task to process one static HTML table. The more challenging task is to extract and save information from tables located in multiple and poorly organized websites. Legal and ethical aspects of web harvesting are discussed as well. The paper demonstrates two case studies. The first one shows how to extract various types of information about the Good Country Index from the multiple web pages, load it into one attribute table and map the results. The second case study shows how script tools and GIS can be used to extract information from one hundred thirty six websites about Nova Scotia wines. In a little more than three minutes a database containing one hundred and six liquor stores selling these wines is created. Then the availability and spatial distribution of various types of wines (by grape types, by wineries, and by liquor stores) are mapped and analyzed.

Harvesting Atlantic Cod under Climate Variability

NASA Astrophysics Data System (ADS)

Oremus, K. L.

2016-12-01

Previous literature links the growth of a fishery to climate variability. This study uses an age-structured bioeconomic model to compare optimal harvest in the Gulf of Maine Atlantic cod fishery under a variable climate versus a static climate. The optimal harvest path depends on the relationship between fishery growth and the interest rate, with higher interest rates dictating greater harvests now at the cost of long-term stock sustainability. Given the time horizon of a single generation of fishermen under assumptions of a static climate, the model finds that the economically optimal management strategy is to harvest the entire stock in the short term and allow the fishery to collapse. However, if the biological growth of the fishery is assumed to vary with climate conditions, such as the North Atlantic Oscillation, there will always be pulses of high growth in the stock. During some of these high-growth years, the growth of the stock and its economic yield can exceed the growth rate of the economy even under high interest rates. This implies that it is not economically optimal to exhaust the New England cod fishery if NAO is included in the biological growth function. This finding may have theoretical implications for the management of other renewable yet exhaustible resources whose growth rates are subject to climate variability.

Light-Harvesting Organic Nanocrystals Capable of Photon Upconversion.

PubMed

Li, Li; Zeng, Yi; Yu, Tianjun; Chen, Jinping; Yang, Guoqiang; Li, Yi

2017-11-23

Harvesting and converting low energy photons into higher ones through upconversion have great potential in solar energy conversion. A light-harvesting nanocrystal assembled from 9,10-distyrylanthracene and palladium(II) meso-tetraphenyltetrabenzoporphyrin as the acceptor and the sensitizer, respectively effects red-to-green upconversion under incoherent excitation of low power density. An upconversion quantum yield of 0.29±0.02 % is obtained upon excitation with 640 nm laser of 120 mW cm -2 . The well-organized packing of acceptor molecules with aggregation-induced emission in the nanocrystals dramatically reduces the nonradiative decay of the excited acceptor, benefits the triplet-triplet annihilation (TTA) upconversion and guides the consequent upconverted emission. This work provides a straightforward strategy to develop light-harvesting nanocrystals based on TTA upconversion, which is attractive for energy conversion and photonic applications. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Modelling drought-related yield losses in Iberia using remote sensing and multiscalar indices

NASA Astrophysics Data System (ADS)

Ribeiro, Andreia F. S.; Russo, Ana; Gouveia, Célia M.; Páscoa, Patrícia

2018-04-01

The response of two rainfed winter cereal yields (wheat and barley) to drought conditions in the Iberian Peninsula (IP) was investigated for a long period (1986-2012). Drought hazard was evaluated based on the multiscalar Standardized Precipitation Evapotranspiration Index (SPEI) and three remote sensing indices, namely the Vegetation Condition (VCI), the Temperature Condition (TCI), and the Vegetation Health (VHI) Indices. A correlation analysis between the yield and the drought indicators was conducted, and multiple linear regression (MLR) and artificial neural network (ANN) models were established to estimate yield at the regional level. The correlation values suggested that yield reduces with moisture depletion (low values of VCI) during early-spring and with too high temperatures (low values of TCI) close to the harvest time. Generally, all drought indicators displayed greatest influence during the plant stages in which the crop is photosynthetically more active (spring and summer), rather than the earlier moments of plants life cycle (autumn/winter). Our results suggested that SPEI is more relevant in the southern sector of the IP, while remote sensing indices are rather good in estimating cereal yield in the northern sector of the IP. The strength of the statistical relationships found by MLR and ANN methods is quite similar, with some improvements found by the ANN. A great number of true positives (hits) of occurrence of yield-losses exhibiting hit rate (HR) values higher than 69% was obtained.

Simulation modeling to explore the effects of length-based harvest regulations for Ictalurus fisheries

USGS Publications Warehouse

Stewart, David R.; Long, James M.; Shoup, Daniel E.

2016-01-01

Management of Blue Catfish Ictalurus furcatus and Channel Catfish I. punctatus for trophy production has recently become more common. Typically, trophy management is attempted with length-based regulations that allow for the moderate harvest of small fish but restrict the harvest of larger fish. However, the specific regulations used vary considerably across populations, and no modeling efforts have evaluated their effectiveness. We used simulation modeling to compare total yield, trophy biomass (Btrophy), and sustainability (spawning potential ratio [SPR] > 0.30) of Blue Catfish and Channel Catfish populations under three scenarios: (1) current regulation (typically a length-based trophy regulation), (2) the best-performing minimum length regulation (MLRbest), and (3) the best-performing length-based trophy catfish regulation (LTRbest; “best performing” was defined as the regulation that maximized yield, Btrophy, and sustainability). The Btrophy produced did not differ among the three scenarios. For each fishery, the MLRbest and LTRbest produced greater yield (>22% more) than the current regulation and maintained sustainability at higher finite exploitation rates (>0.30) than the current regulation. The MLRbest and LTRbest produced similar yields and SPRs for Channel Catfish and similar yields for Blue Catfish; however, the MLRbest for Blue Catfish produced more resilient fisheries (higher SPR) than the LTRbest. Overall, the variation in yield, Btrophy, and SPR among populations was greater than the variation among regulations applied to any given population, suggesting that population-specific regulations may be preferable to regulations applied to geographic regions. We conclude that LTRs are useful for improving catfish yield and maintaining sustainability without overly restricting harvest but are not effective at increasing the Btrophy of catfish.

Linking Field and Satellite Observations to Reveal Differences in Single vs. Double-Cropped Soybean Yields in Central Brazil

NASA Astrophysics Data System (ADS)

Jeffries, G. R.; Cohn, A.

2016-12-01

Soy-corn double cropping (DC) has been widely adopted in Central Brazil alongside single cropped (SC) soybean production. DC involves different cropping calendars, soy varieties, and may be associated with different crop yield patterns and volatility than SC. Study of the performance of the region's agriculture in a changing climate depends on tracking differences in the productivity of SC vs. DC, but has been limited by crop yield data that conflate the two systems. We predicted SC and DC yields across Central Brazil, drawing on field observations and remotely sensed data. We first modeled field yield estimates as a function of remotely sensed DC status and vegetation index (VI) metrics, and other management and biophysical factors. We then used the statistical model estimated to predict SC and DC soybean yields at each 500 m2 grid cell of Central Brazil for harvest years 2001 - 2015. The yield estimation model was constructed using 1) a repeated cross-sectional survey of soybean yields and management factors for years 2007-2015, 2) a custom agricultural land cover classification dataset which assimilates earlier datasets for the region, and 3) 500m 8-day MODIS image composites used to calculate the wide dynamic range vegetation index (WDRVI) and derivative metrics such as area under the curve for WDRVI values in critical crop development periods. A statistical yield estimation model which primarily entails WDRVI metrics, DC status, and spatial fixed effects was developed on a subset of the yield dataset. Model validation was conducted by predicting previously withheld yield records, and then assessing error and goodness-of-fit for predicted values with metrics including root mean squared error (RMSE), mean squared error (MSE), and R2. We found a statistical yield estimation model which incorporates WDRVI and DC status to be way to estimate crop yields over the region. Statistical properties of the resulting gridded yield dataset may be valuable for understanding

Responses of root physiological characteristics and yield of sweet potato to humic acid urea fertilizer

PubMed Central

Kou, Meng; Tang, Zhonghou; Zhang, Aijun; Li, Hongmin; Wei, Meng

2017-01-01

Humic acid (HA), not only promote the growth of crop roots, they can be combined with nitrogen (N) to increase fertilizer use efficiency and yield. However, the effects of HA urea fertilizer (HA-N) on root growth and yield of sweet potato has not been widely investigated. Xushu 28 was used as the experimental crop to investigate the effects of HA-N on root morphology, active oxygen metabolism and yield under field conditions. Results showed that nitrogen application alone was not beneficial for root growth and storage root formation during the early growth stage. HA-N significantly increased the dry weight of the root system, promoted differentiation from adventitious root to storage root, and increased the overall root activity, total root length, root diameter, root surface area, as well as root volume. HA-N thus increased the activity of superoxide dismutase (SOD), peroxidase (POD), and Catalase (CAT) as well as increasing the soluble protein content of roots and decreasing the malondialdehyde (MDA) content. HA-N significantly increased both the number of storage roots per plant increased by 14.01%, and the average fresh weight per storage root increased by 13.7%, while the yield was also obviously increased by 29.56%. In this study, HA-N increased yield through a synergistic increase of biological yield and harvest index. PMID:29253886

Assimilating remote sensing observations of leaf area index and soil moisture for wheat yield estimates: An observing system simulation experiment

USDA-ARS?s Scientific Manuscript database

We develop a robust understanding of the effects of assimilating remote sensing observations of leaf area index and soil moisture (in the top 5 cm) on DSSAT-CSM CropSim-Ceres wheat yield estimates. Synthetic observing system simulation experiments compare the abilities of the Ensemble Kalman Filter...

Assimilating a synthetic Kalman filter leaf area index series into the WOFOST model to improve regional winter wheat yield estimation

USDA-ARS?s Scientific Manuscript database

The scale mismatch between remotely sensed observations and crop growth models simulated state variables decreases the reliability of crop yield estimates. To overcome this problem, we used a two-step data assimilation phases: first we generated a complete leaf area index (LAI) time series by combin...

Sediment and Runoff Losses following Harvesting/Site Prep Operations on a Piedmont Soil in Alabama

Treesearch

Johnny M. III Grace; Emily A. Carter

2001-01-01

Impacts of soil erosion on water quality from forest harvesting and site preparation have received increased concern in recent years. The study presented here was performed in Lee County, Alabama to investigate the impact of harvesting and site preparation on a 20-year-old loblolly pine (Pinus taeda L.) plantation on sediment and runoff yield....

Ginning picker and stripper harvested high plains cotton - update

USDA-ARS?s Scientific Manuscript database

Texas High Plains cotton has improved over the last ten years with regard to yield and High Volume Instrument (HVI) fiber quality. Harvesting and ginning practices are needed which preserve fiber quality and maximize return to the producer. The objective of this work is to investigate the influence ...

Determining the sputter yields of molybdenum in low-index crystal planes via electron backscattered diffraction, focused ion beam and atomic force microscope

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, H.S., E-mail: 160184@mail.csc.com.tw; Chiu, C.H.; Hong, I.T.

2013-09-15

Previous literature has used several monocrystalline sputtering targets with various crystalline planes, respectively, to investigate the variations of the sputter yield of materials in different crystalline orientations. This study presents a method to measure the sputtered yields of Mo for the three low-index planes (100), (110), and (111), through using an easily made polycrystalline target. The procedure was firstly to use electron backscattered diffraction to identify the grain positions of the three crystalline planes, and then use a focused ion beam to perform the micro-milling of each identified grain, and finally the sputter yields were calculated from the removed volumes,more » which were measured by atomic force microscope. Experimental results showed that the sputter yield of the primary orientations for Mo varied as Y{sub (110)} > Y{sub (100)} > Y{sub (111)}, coincidental with the ranking of their planar atomic packing densities. The concept of transparency of ion in the crystalline substance was applied to elucidate these results. In addition, the result of (110) orientation exhibiting higher sputter yield is helpful for us to develop a Mo target with a higher deposition rate for use in industry. By changing the deformation process from straight rolling to cross rolling, the (110) texture intensity of the Mo target was significantly improved, and thus enhanced the deposition rate. - Highlights: • We used EBSD, FIB and AFM to measure the sputter yields of Mo in low-index planes. • The sputter yield of the primary orientations for Mo varied as Y{sub (110)} > Y{sub (100)} > Y{sub (111)}. • The transparency of ion was used to elucidate the differences in the sputter yield. • We improved the sputter rate of polycrystalline Mo target by adjusting its texture.« less

RELIABILITY TESTING OF AN ON-HARVESTER COTTON WEIGHT MEASUREMENT SYSTEM

USDA-ARS?s Scientific Manuscript database

A system for weighing seed cotton onboard stripper harvesters was developed and installed on several producer owned and operated machines. The weight measurement system provides critical information to producers when in the process of calibrating yield monitors or conducting on-farm research. The ...

Regional crop gross primary production and yield estimation using fused Landsat-MODIS data

NASA Astrophysics Data System (ADS)

He, M.; Kimball, J. S.; Maneta, M. P.; Maxwell, B. D.; Moreno, A.

2017-12-01

Accurate crop yield assessments using satellite-based remote sensing are of interest for the design of regional policies that promote agricultural resiliency and food security. However, the application of current vegetation productivity algorithms derived from global satellite observations are generally too coarse to capture cropland heterogeneity. Merging information from sensors with reciprocal spatial and temporal resolution can improve the accuracy of these retrievals. In this study, we estimate annual crop yields for seven important crop types -alfalfa, barley, corn, durum wheat, peas, spring wheat and winter wheat over Montana, United States (U.S.) from 2008 to 2015. Yields are estimated as the product of gross primary production (GPP) and a crop-specific harvest index (HI) at 30 m spatial resolution. To calculate GPP we used a modified form of the MOD17 LUE algorithm driven by a 30 m 8-day fused NDVI dataset constructed by blending Landsat (5 or 7) and MODIS Terra reflectance data. The fused 30-m NDVI record shows good consistency with the original Landsat and MODIS data, but provides better spatiotemporal information on cropland vegetation growth. The resulting GPP estimates capture characteristic cropland patterns and seasonal variations, while the estimated annual 30 m crop yield results correspond favorably with county-level crop yield data (r=0.96, p<0.05). The estimated crop yield performance was generally lower, but still favorable in relation to field-scale crop yield surveys (r=0.42, p<0.01). Our methods and results are suitable for operational applications at regional scales.

Yield and nutritive value of photoperiod-sensitive sorghum and sorghum-sudangrass in central Wisconsin

USDA-ARS?s Scientific Manuscript database

A study was conducted to evaluate the yield and nutrient composition of photoperiod sensitive (PS) and non-PS forage sorghum, sorghum-sudangrass, and sudangrass compared to corn planted on 2 dates and harvested using single or multiple-cut harvest strategies at 2 research stations (Marshfield and Ha...

Live growth performance, carcass grading characteristics, and harvest yields of beef steers supplemented zilpaterol hydrochloride and offered ad libitum or maintenance energy intake.

PubMed

Judy Walter, Lee-Anne; Schmitz, Angela Nicole; Nichols, Wade Taylor; Hutcheson, John Paul; Lawrence, Ty Ellis

2018-05-04

A trial was conducted to examine live growth efficiency, harvest yields, and carcass grading performance of steers fed at maintenance (M) or at ad libitum (A) level of intake during zilpaterol hydrochloride (Z) supplementation. Single-sired, beef steers (n = 56; start of trial BW 590 ± 36 kg) blocked (n = 2) by weight and terminal implant were sorted into pairs (n = 14 per block) by weight. Pairs of steers were initially assigned to 0, 28, or 56 d of feeding. Within 28 or 56 d, pairs were assigned to M or A intake. Steers within a pair assigned to 56 d of feeding were randomly assigned to either 20 d of Z supplementation (90 mg/d per steer) with a 4 d withdrawal period prior to slaughter or to no ZH supplementation (C). Steers were housed and fed in individual pens. Weights of all non-carcass and carcass components were recorded at slaughter; carcasses were graded 24-h postmortem. Data were analyzed via a mixed model; the fixed effect was treatment combination with random effects of block and pair. Live growth data used harvest day as the repeated measure and animal as the subject. Single df contrasts were constructed for day 0 vs. day 28, day 0 vs. day 56, day 28 vs. day 56, M vs. A, and C vs. Z. Treatment impacted (P ≤ 0.05) live ADG; contrasts indicated A (1.33) was greater than M (0.14 kg), and Z (1.12) was greater than C (0.82 kg). Similarly, carcass ADG differences (P < 0.01) indicated A (1.04) was greater than M (0.36 kg), and Z (1.35) was greater than C (0.71 kg). Intake level altered BW and empty body weight (EBW); M cattle had reduced BW and EBW (P < 0.01, 585 and 540 kg) than A cattle (647 and 597 kg). Cattle fed at M had less carcass and internal cavity mass (P < 0.01, 359 and 79.4 kg) than A cattle (394 and 93.5 kg). Liver mass was reduced by M feeding (P < 0.01; M-5.03, A-6.69 kg) and Z treatment (P < 0.01; Z-5.64, C-6.06 kg). Moreover, mass of total splanchnic tissue was less (P < 0.01) for M cattle than A cattle (59.8 vs. 72.5 kg). Dressed

Harvesting minor forest products in the Pacific Northwest.

Treesearch

Thomas C. Adams

1960-01-01

Forests of the Pacific Northwest yield a number of secondary or so-called minor forest products. These include those smaller, side-line items of commercial value that can usually be harvested without intensive management or cultivation. They are generally only incidental to a primary use of the land for sawtimber or pulpwood production. In most cases they can be...

PROFIT-PC: a program for estimating maximum net revenue from multiproduct harvests in Appalachian hardwoods

Treesearch

Chris B. LeDoux; John E. Baumgras; R. Bryan Selbe

1989-01-01

PROFIT-PC is a menu driven, interactive PC (personal computer) program that estimates optimum product mix and maximum net harvesting revenue based on projected product yields and stump-to-mill timber harvesting costs. Required inputs include the number of trees/acre by species and 2 inches diameter at breast-height class, delivered product prices by species and product...

Veneer grade yield from pruned Douglas-fir.

Treesearch

Edward J. II Dimock; Henry H. Haskell

1962-01-01

This paper reports actual veneer yields obtained from 10 trees pruned at age 38 and harvested 20 years later. Information of this kind is needed to help determine if and when to prune and ultimately will be essential to a thorough economic analysis of expected returns from pruning.

Response of Pink Lady® apples to post-harvest application of 1-methylcyclopropene as a function of applied dose, maturity at harvest, storage time and controlled atmosphere storage.

PubMed

Cocci, Emiliano; Sacchetti, Giampiero; Rocculi, Pietro; Dalla Rosa, Marco

2014-10-01

1-Methylcyclopropene (1-MCP) is an inhibitor of ethylene reception used in post-harvest treatments to delay fruit ripening. Several factors affect the efficacy of 1-MCP treatments. The effect of a post-harvest treatment with 1-MCP on the quality of Pink Lady® apples as a function of 1-MCP dose, storage time and maturity at harvest was investigated. 1-MCP treatment was further tested in combination with controlled atmosphere (CA) storage. 1-MCP limited fruit respiration and softening during storage and was more effective on partially matured fruits and at prolonged storage times. The delaying of 1-MCP on the increase of ripening index was greater on matured fruits at prolonged storage times. The combination of 1-MCP and CA treatments positively affected quality indices of mature apples during 6 months of storage and 7 days of commercial life, with 1-MCP being more effective than CA. 1-MCP and CA showed positive combined effects on firmness and ripening index after 6 months of storage, and on firmness and CO₂ production after a further 7 days of commercial life. By knowing fruit maturity at harvest and expected storage time it is possible to choose the most suitable 1-MCP dose to meet the market requirements by applying a simple polynomial model. © 2014 Society of Chemical Industry.

Lymph node harvest in colon and rectal cancer: Current considerations

PubMed Central

McDonald, James R; Renehan, Andrew G; O’Dwyer, Sarah T; Haboubi, Najib Y

2012-01-01

The prognostic significance of identifying lymph node (LN) metastases following surgical resection for colon and rectal cancer is well recognized and is reflected in accurate staging of the disease. An established body of evidence exists, demonstrating an association between a higher total LN count and improved survival, particularly for node negative colon cancer. In node positive disease, however, the lymph node ratios may represent a better prognostic indicator, although the impact of this on clinical treatment has yet to be universally established. By extension, strategies to increase surgical node harvest and/or laboratory methods to increase LN yield seem logical and might improve cancer staging. However, debate prevails as to whether or not these extrapolations are clinically relevant, particularly when very high LN counts are sought. Current guidelines recommend a minimum of 12 nodes harvested as the standard of care, yet the evidence for such is questionable as it is unclear whether an increasing the LN count results in improved survival. Findings from modern treatments, including down-staging in rectal cancer using pre-operative chemoradiotherapy, paradoxically suggest that lower LN count, or indeed complete absence of LNs, are associated with improved survival; implying that using a specific number of LNs harvested as a measure of surgical quality is not always appropriate. The pursuit of a sufficient LN harvest represents good clinical practice; however, recent evidence shows that the exhaustive searching for very high LN yields may be unnecessary and has little influence on modern approaches to treatment. PMID:22347537

Impacts of management practices on bioenergy feedstock yield and economic feasibility on Conservation Reserve Program grasslands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Eric K.; Aberle, Ezra; Chen, Chengci

Perennial grass mixtures planted on Conservation Reserve Program (CRP) land are a potential source of dedicated bioenergy feedstock. Long-term nitrogen (N) and harvest management are critical factors for maximizing biomass yield while maintaining the longevity of grass stands. A six-year farm-scale study was conducted to understand the impact of weather variability on biomass yield, determine optimal N fertilization and harvest timing management practices for sustainable biomass production, and estimate economic viability at six CRP sites in the United States. Precipitation during the growing season was a critical factor for annual biomass production across all regions, and annual biomass production wasmore » severely reduced when growing season precipitation was below 50% of average. The N rate of 112 kg ha -1 produced the highest biomass yield at each location. Harvest timing resulting in the highest biomass yield was site-specific and was a factor of predominant grass type, seasonal precipitation, and the number of harvests taken per year. The use of N fertilizer for yield enhancement unambiguously increased the cost of biomass regardless of the harvest timing for all six sites. The breakeven price of biomass at the farmgate ranged from 37 dollars to 311 dollars Mg -1 depending on the rate of N application, timing of harvesting, and location when foregone opportunity costs were not considered. Breakeven prices ranged from 69 dollars to 526 dollars Mg -1 when the loss of CRP land rental payments was included as an opportunity cost. Annual cost of the CRP to the federal government could be reduced by over 8% in the states included in this study; however, this would require the biomass price to be much higher than in the case where the landowner receives the CRP land rent. Lastly, this field research demonstrated the importance of long-term, farm-scale research for accurate estimation of biomass feedstock production and economic viability from perennial

Impacts of management practices on bioenergy feedstock yield and economic feasibility on Conservation Reserve Program grasslands

DOE PAGES

Anderson, Eric K.; Aberle, Ezra; Chen, Chengci; ...

2015-12-21

Perennial grass mixtures planted on Conservation Reserve Program (CRP) land are a potential source of dedicated bioenergy feedstock. Long-term nitrogen (N) and harvest management are critical factors for maximizing biomass yield while maintaining the longevity of grass stands. A six-year farm-scale study was conducted to understand the impact of weather variability on biomass yield, determine optimal N fertilization and harvest timing management practices for sustainable biomass production, and estimate economic viability at six CRP sites in the United States. Precipitation during the growing season was a critical factor for annual biomass production across all regions, and annual biomass production wasmore » severely reduced when growing season precipitation was below 50% of average. The N rate of 112 kg ha -1 produced the highest biomass yield at each location. Harvest timing resulting in the highest biomass yield was site-specific and was a factor of predominant grass type, seasonal precipitation, and the number of harvests taken per year. The use of N fertilizer for yield enhancement unambiguously increased the cost of biomass regardless of the harvest timing for all six sites. The breakeven price of biomass at the farmgate ranged from 37 dollars to 311 dollars Mg -1 depending on the rate of N application, timing of harvesting, and location when foregone opportunity costs were not considered. Breakeven prices ranged from 69 dollars to 526 dollars Mg -1 when the loss of CRP land rental payments was included as an opportunity cost. Annual cost of the CRP to the federal government could be reduced by over 8% in the states included in this study; however, this would require the biomass price to be much higher than in the case where the landowner receives the CRP land rent. Lastly, this field research demonstrated the importance of long-term, farm-scale research for accurate estimation of biomass feedstock production and economic viability from perennial

Nitrogen and tillage management affect corn cellulosic yield, composition, and ethanol potential

USDA-ARS?s Scientific Manuscript database

Corn (Zea mays L.) stover and cobs remaining after grain harvest can serve as a feedstock for cellulosic ethanol production. Field trials were conducted at two locations in Minnesota over three years to determine how corn cellulosic yield composition and ethanol yield are influenced by tillage syste...

Gas Exchange, Transpiration and Yield of Sweetpotato Grown in a Controlled Environment

NASA Technical Reports Server (NTRS)

Barta, Daniel J.; Henderson, Keith E.; Mortley, Desmond G.; Henninger, Donald L.

2000-01-01

Sweetpotato was grown to harvest maturity within NASA Johnson Space Center's Variable Pressure Growth Chamber (VPGC) to characterize crop performance for potential use in advanced life support systems as a contributor to food production, air revitalization and resource recovery. Stem cuttings of breeding clone "TU-82-155" were grown hydroponically at a density of 17 plants m(sup -2) using a modified pressure-plate growing system (Patent No. 4860-490, Tuskegee University). Lighting was provided by HPS lamps at a photoperiod of 12h light: 12h dark. The photosynthetic photon flux was maintained at 500, 750 and 1000 micro mol m(sup -2) s(sub -1) during days 1-15, 16-28, 29-119, respectively. Canopy temperatures were maintained at 28 C: light: 22 C:dark. During the light period, relative humidity and carbon dioxide were maintained at 70% and 1200 micro liters l(sup -1), respectively. Nutrient solution was manually adjusted 2 to 4 times per week by addition of 10X concentrated modified half-strength Hoagland nutrient salts and NaOH to return the electrical conductivity and pH to 1.2 mS cm(sup -1) and 6.0, respectively. At 17 weeks (119 days) from transplanting, a total of 56.5 kilograms fresh mass of storage roots (84.1% moisture) were harvested from the 11.2 m(sup 2) chamber, resulting in a yield 5.0 kilograms m(sup -2). Harvest index, based on fresh mass, was 38.6%. Rates of net photosynthesis, dark respiration, transpiration, and ethylene production will be reported.

Improving genomic prediction for pre-harvest sprouting tolerance in wheat by weighting large-effect quantitative trait loci

USDA-ARS?s Scientific Manuscript database

Pre-harvest sprouting (PHS) is a major problem in wheat (Triticum aestivum L.) that occurs when grains in a mature spike germinate prior to harvest, resulting in reduced yield, quality, and grain sale price. Improving PHS tolerance (PHST) is a challenge to wheat breeders because it is quantitatively...

The effect of seasonal harvesting on stage-structured population models.

PubMed

Tang, Sanyi; Chen, Lansun

2004-04-01

In most models of population dynamics, increases in population due to birth are assumed to be time-independent, but many species reproduce only during a single period of the year. We propose an exploited single-species model with stage structure for the dynamics in a fish population for which births occur in a single pulse once per time period. Since birth pulse populations are often characterized with a discrete time dynamical system determined by its Poincaré map, we explore the consequences of harvest timing to equilibrium population sizes under seasonal dependence and obtain threshold conditions for their stability, and show that the timing of harvesting has a strong impact on the persistence of the fish population, on the volume of mature fish stock and on the maximum annual-sustainable yield. Moreover, our results imply that the population can sustain much higher harvest rates if the mature fish is removed as early in the season (after the birth pulse) as possible. Further, the effects of harvesting effort and harvest timing on the dynamical complexity are also investigated. Bifurcation diagrams are constructed with the birth rate (or harvesting effort or harvest timing) as the bifurcation parameter, and these are observed to display rich structure, including chaotic bands with periodic windows, pitch-fork and tangent bifurcations, non-unique dynamics (meaning that several attractors coexist) and attractor crisis. This suggests that birth pulse, in effect, provides a natural period or cyclicity that makes the dynamical behavior more complex.

Genetic Improvements in Rice Yield and Concomitant Increases in Radiation- and Nitrogen-Use Efficiency in Middle Reaches of Yangtze River

PubMed Central

Zhu, Guanglong; Peng, Shaobing; Huang, Jianliang; Cui, Kehui; Nie, Lixiao; Wang, Fei

2016-01-01

The yield potential of rice (Oryza sativa L.) has experienced two significant growth periods that coincide with the introduction of semi-dwarfism and the utilization of heterosis. In present study, we determined the annual increase in the grain yield of rice varieties grown from 1936 to 2005 in Middle Reaches of Yangtze River and examined the contributions of RUE (radiation-use efficiency, the conversion efficiency of pre-anthesis intercepted global radiation to biomass) and NUE (nitrogen-use efficiency, the ratio of grain yield to aboveground N accumulation) to these improvements. An examination of the 70-year period showed that the annual gains of 61.9 and 75.3 kg ha−1 in 2013 and 2014, respectively, corresponded to an annual increase of 1.18 and 1.16% in grain yields, respectively. The improvements in grain yield resulted from increases in the harvest index and biomass, and the sink size (spikelets per panicle) was significantly enlarged because of breeding for larger panicles. Improvements were observed in RUE and NUE through advancements in breeding. Moreover, both RUE and NUE were significantly correlated with the grain yield. Thus, our study suggests that genetic improvements in rice grain yield are associated with increased RUE and NUE. PMID:26876641

Temperature, Sowing and Harvest Dates, and Yield of Maize in the Southwestern US

NASA Astrophysics Data System (ADS)

Kafatos, M.; Stack, D.; Myoung, B.; Kim, S. H.; Kim, J.

2014-12-01

Since sowing date of maize is sensitive to climate variability and changes, it is of a practical importance to examine how sowing dates affect maize yields in various temperature regimes in the southwestern US. A 21-year (1991-2011) simulation of maize yield using Agricultural Production Systems sIMulator (APSIM) with observed meteorological forcing, shows that earlier sowing dates are favorable for higher yields primarily by increasing the length of growing season in cold mountaineous regions. In these regions, warmer conditions in the sowing period tend to advance the sowing date and then enhance yield. Over low-elevation warm regions, yields are less correlated with sowing dates and the length of growing season, perhaps because growing season temperatures are high enough for fast growth. Instead, in the warm regions, maize yields are sensitive to temperature variations during the late growing season due to adverse effects of extreme high temperature events on maize development.

Water yield issues in the jarrah forest of south-western Australia

NASA Astrophysics Data System (ADS)

Ruprecht, J. K.; Stoneman, G. L.

1993-10-01

The jarrah forest of south-western Australia produces little streamflow from moderate rainfall. Water yield from water supply catchments for Perth, Western Australia, are low, averaging 71 mm (7% of annual rainfall). The low water yields are attributed to the large soil water storage available for continuous use by the forest vegetation. A number of water yield studies in south-western Australia have examined the impact on water yield of land use practices including clearing for agricultural development, forest harvesting and regeneration, forest thinning and bauxite mining. A permanent reduction in forest cover by clearing for agriculture led to permanent increases of water yield of approximately 28% of annual rainfall in a high rainfall catchment. Thinning of a high rainfall catchment led to an increase in water yield of 20% of annual rainfall. However, it is not clear for how long the increased water yield will persist. Forest harvesting and regeneration have led to water yield increases of 16% of annual rainfall. The subsequent recovery of vegetation cover has led to water yields returning to pre-disturbance levels after an estimated 12-15 years. Bauxite mining of a high rainfall catchment led to a water yield increase of 8% of annual rainfall, followed by a return to pre-disturbance water yield after 12 years. The magnitude of specific streamflow generation mechanisms in small catchments subject to forest disturbance vary considerably, typically in a number of distinct stages. The presence of a permanent groundwater discharge area was shown to be instrumental in determining the magnitude of the streamflow response after forest disturbance. The long-term prognosis for water yield from areas subject to forest thinning, harvesting and regeneration, and bauxite mining are uncertain, owing to the complex interrelationship between vegetation cover, tree height and age, and catchment evapotranspiration. Management of the forest for water yield needs to acknowledge

Canopy Chlorophyll Density Based Index for Estimating Nitrogen Status and Predicting Grain Yield in Rice

PubMed Central

Liu, Xiaojun; Zhang, Ke; Zhang, Zeyu; Cao, Qiang; Lv, Zunfu; Yuan, Zhaofeng; Tian, Yongchao; Cao, Weixing; Zhu, Yan

2017-01-01

Canopy chlorophyll density (Chl) has a pivotal role in diagnosing crop growth and nutrition status. The purpose of this study was to develop Chl based models for estimating N status and predicting grain yield of rice (Oryza sativa L.) with Leaf area index (LAI) and Chlorophyll concentration of the upper leaves. Six field experiments were conducted in Jiangsu Province of East China during 2007, 2008, 2009, 2013, and 2014. Different N rates were applied to generate contrasting conditions of N availability in six Japonica cultivars (9915, 27123, Wuxiangjing 14, Wuyunjing 19, Yongyou 8, and Wuyunjing 24) and two Indica cultivars (Liangyoupei 9, YLiangyou 1). The SPAD values of the four uppermost leaves and LAI were measured from tillering to flowering growth stages. Two N indicators, leaf N accumulation (LNA) and plant N accumulation (PNA) were measured. The LAI estimated by LAI-2000 and LI-3050C were compared and calibrated with a conversion equation. A linear regression analysis showed significant relationships between Chl value and N indicators, the equations were as follows: PNA = (0.092 × Chl) − 1.179 (R2 = 0.94, P < 0.001, relative root mean square error (RRMSE) = 0.196), LNA = (0.052 × Chl) − 0.269 (R2 = 0.93, P < 0.001, RRMSE = 0.185). Standardized method was used to quantity the correlation between Chl value and grain yield, normalized yield = (0.601 × normalized Chl) + 0.400 (R2 = 0.81, P < 0.001, RRMSE = 0.078). Independent experimental data also validated the use of Chl value to accurately estimate rice N status and predict grain yield. PMID:29163568

GWAS for plant growth stages and yield components in spring wheat (Triticum aestivum L.) harvested in three regions of Kazakhstan.

PubMed

Turuspekov, Yerlan; Baibulatova, Aida; Yermekbayev, Kanat; Tokhetova, Laura; Chudinov, Vladimir; Sereda, Grigoriy; Ganal, Martin; Griffiths, Simon; Abugalieva, Saule

2017-11-14

Spring wheat is the largest agricultural crop grown in Kazakhstan with an annual sowing area of 12 million hectares in 2016. Annually, the country harvests around 15 million tons of high quality grain. Despite environmental stress factors it is predicted that the use of new technologies may lead to increases in productivity from current levels of 1.5 to up to 3 tons per hectare. One way of improving wheat productivity is by the application of new genomic oriented approaches in plant breeding projects. Genome wide association studies (GWAS) are emerging as powerful tools for the understanding of the inheritance of complex traits via utilization of high throughput genotyping technologies and phenotypic assessments of plant collections. In this study, phenotyping and genotyping data on 194 spring wheat accessions from Kazakhstan, Russia, Europe, and CIMMYT were assessed for the identification of marker-trait associations (MTA) of agronomic traits by using GWAS. Field trials in Northern, Central and Southern regions of Kazakhstan using 194 spring wheat accessions revealed strong correlations of yield with booting date, plant height, biomass, number of spikes per plant, and number of kernels per spike. The accessions from Europe and CIMMYT showed high breeding potential for Southern and Central regions of the country in comparison with the performance of the local varieties. The GGE biplot method, using average yield per plant, suggested a clear separation of accessions into their three breeding origins in relationship to the three environments in which they were evaluated. The genetic variation in the three groups of accessions was further studied using 3245 polymorphic SNP (single nucleotide polymorphism) markers. The application of Principal Coordinate analysis clearly grouped the 194 accessions into three clades according to their breeding origins. GWAS on data from nine field trials allowed the identification of 114 MTAs for 12 different agronomic traits. Field

Optimization of Light-Harvesting Pigment Improves Photosynthetic Efficiency.

PubMed

Jin, Honglei; Li, Mengshu; Duan, Sujuan; Fu, Mei; Dong, Xiaoxiao; Liu, Bing; Feng, Dongru; Wang, Jinfa; Wang, Hong-Bin

2016-11-01

Maximizing light capture by light-harvesting pigment optimization represents an attractive but challenging strategy to improve photosynthetic efficiency. Here, we report that loss of a previously uncharacterized gene, HIGH PHOTOSYNTHETIC EFFICIENCY1 (HPE1), optimizes light-harvesting pigments, leading to improved photosynthetic efficiency and biomass production. Arabidopsis (Arabidopsis thaliana) hpe1 mutants show faster electron transport and increased contents of carbohydrates. HPE1 encodes a chloroplast protein containing an RNA recognition motif that directly associates with and regulates the splicing of target RNAs of plastid genes. HPE1 also interacts with other plastid RNA-splicing factors, including CAF1 and OTP51, which share common targets with HPE1. Deficiency of HPE1 alters the expression of nucleus-encoded chlorophyll-related genes, probably through plastid-to-nucleus signaling, causing decreased total content of chlorophyll (a+b) in a limited range but increased chlorophyll a/b ratio. Interestingly, this adjustment of light-harvesting pigment reduces antenna size, improves light capture, decreases energy loss, mitigates photodamage, and enhances photosynthetic quantum yield during photosynthesis. Our findings suggest a novel strategy to optimize light-harvesting pigments that improves photosynthetic efficiency and biomass production in higher plants. © 2016 American Society of Plant Biologists. All Rights Reserved.

Sensorless Estimation and Nonlinear Control of a Rotational Energy Harvester

NASA Astrophysics Data System (ADS)

Nunna, Kameswarie; Toh, Tzern T.; Mitcheson, Paul D.; Astolfi, Alessandro

2013-12-01

It is important to perform sensorless monitoring of parameters in energy harvesting devices in order to determine the operating states of the system. However, physical measurements of these parameters is often a challenging task due to the unavailability of access points. This paper presents, as an example application, the design of a nonlinear observer and a nonlinear feedback controller for a rotational energy harvester. A dynamic model of a rotational energy harvester with its power electronic interface is derived and validated. This model is then used to design a nonlinear observer and a nonlinear feedback controller which yield a sensorless closed-loop system. The observer estimates the mechancial quantities from the measured electrical quantities while the control law sustains power generation across a range of source rotation speeds. The proposed scheme is assessed through simulations and experiments.

Climate Change Decouples Drought from Early Wine Grape Harvests in France

NASA Technical Reports Server (NTRS)

Cook, Benjamin I.; Wolkovich, Elizabeth M.

2016-01-01

Across the world, wine grape phenology has advanced in recent decades, in step with climate-change-induced trends in temperature - the main driver of fruit maturation - and drought. Fully understanding how climate change contributes to changes in harvest dates, however, requires analysing wine grape phenology and its relationship to climate over a longer-term context, including data predating anthropogenic interference in the climate system. Here, we investigate the climatic controls of wine grape harvest dates from 1600-2007 in France and Switzerland using historical harvest and climate data. Early harvests occur with warmer temperatures (minus 6 days per degree Centigrade) and are delayed by wet conditions (plus 0.07 days per millimeter; plus 1.68 days per PDSI (Palmer drought severity index)) during spring and summer. In recent decades (1981-2007), however, the relationship between harvest timing and drought has broken down. Historically, high summer temperatures in Western Europe, which would hasten fruit maturation, required drought conditions to generate extreme heat. The relationship between drought and temperature in this region, however, has weakened in recent decades and enhanced warming from anthropogenic greenhouse gases can generate the high temperatures needed for early harvests without drought. Our results suggest that climate change has fundamentally altered the climatic drivers of early wine grape harvests in France, with possible ramifications for viticulture management and wine quality.

Light-harvesting photocatalysis for water oxidation using mesoporous organosilica.

PubMed

Takeda, Hiroyuki; Ohashi, Masataka; Goto, Yasutomo; Ohsuna, Tetsu; Tani, Takao; Inagaki, Shinji

2014-07-14

An organic-based photocatalysis system for water oxidation, with visible-light harvesting antennae, was constructed using periodic mesoporous organosilica (PMO). PMO containing acridone groups in the framework (Acd-PMO), a visible-light harvesting antenna, was supported with [Ru(II)(bpy)3(2+)] complex (bpy = 2,2'-bipyridyl) coupled with iridium oxide (IrO(x)) particles in the mesochannels as photosensitizer and catalyst, respectively. Acd-PMO absorbed visible light and funneled the light energy into the Ru complex in the mesochannels through excitation energy transfer. The excited state of Ru complex is oxidatively quenched by a sacrificial oxidant (Na2S2O8) to form Ru(3+) species. The Ru(3+) species extracts an electron from IrO(x) to oxidize water for oxygen production. The reaction quantum yield was 0.34 %, which was improved to 0.68 or 1.2 % by the modifications of PMO. A unique sequence of reactions mimicking natural photosystem II, 1) light-harvesting, 2) charge separation, and 3) oxygen generation, were realized for the first time by using the light-harvesting PMO. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Grain Yield and Water Use Efficiency in Extremely-Late Sown Winter Wheat Cultivars under Two Irrigation Regimes in the North China Plain

PubMed Central

Wang, Bin; Zhang, Yinghua; Hao, Baozhen; Xu, Xuexin; Zhao, Zhigan; Wang, Zhimin; Xue, Qingwu

2016-01-01

Wheat production is threatened by water shortages and groundwater over-draft in the North China Plain (NCP). In recent years, winter wheat has been increasingly sown extremely late in early to mid-November after harvesting cotton or pepper. To improve water use efficiency (WUE) and guide the extremely late sowing practices, a 3-year field experiment was conducted under two irrigation regimes (W1, one-irrigation, 75 mm at jointing; W2, two-irrigation, 75 mm at jointing and 75 mm at anthesis) in 3 cultivars differing in spike size (HS4399, small spike; JM22, medium spike; WM8, large spike). Wheat was sown in early to mid-November at a high seeding rate of 800–850 seeds m−2. Average yields of 7.42 t ha−1 and WUE of 1.84 kg m−3 were achieved with an average seasonal evapotranspiration (ET) of 404 mm. Compared with W2, wheat under W1 did not have yield penalty in 2 of 3 years, and had 7.9% lower seasonal ET and 7.5% higher WUE. The higher WUE and stable yield under W1 was associated with higher 1000-grain weight (TGW) and harvest index (HI). Among the 3 cultivars, JM22 had 5.9%–8.9% higher yield and 4.2%–9.3% higher WUE than WM8 and HS4399. The higher yield in JM22 was attributed mainly to higher HI and TGW due to increased post-anthesis biomass and deeper seasonal soil water extraction. In conclusion, one-irrigation with a medium-sized spike cultivar JM22 could be a useful strategy to maintain yield and high WUE in extremely late-sown winter wheat at a high seeding rate in the NCP. PMID:27100187

Grain Yield and Water Use Efficiency in Extremely-Late Sown Winter Wheat Cultivars under Two Irrigation Regimes in the North China Plain.

PubMed

Wang, Bin; Zhang, Yinghua; Hao, Baozhen; Xu, Xuexin; Zhao, Zhigan; Wang, Zhimin; Xue, Qingwu

2016-01-01

Wheat production is threatened by water shortages and groundwater over-draft in the North China Plain (NCP). In recent years, winter wheat has been increasingly sown extremely late in early to mid-November after harvesting cotton or pepper. To improve water use efficiency (WUE) and guide the extremely late sowing practices, a 3-year field experiment was conducted under two irrigation regimes (W1, one-irrigation, 75 mm at jointing; W2, two-irrigation, 75 mm at jointing and 75 mm at anthesis) in 3 cultivars differing in spike size (HS4399, small spike; JM22, medium spike; WM8, large spike). Wheat was sown in early to mid-November at a high seeding rate of 800-850 seeds m(-2). Average yields of 7.42 t ha(-1) and WUE of 1.84 kg m(-3) were achieved with an average seasonal evapotranspiration (ET) of 404 mm. Compared with W2, wheat under W1 did not have yield penalty in 2 of 3 years, and had 7.9% lower seasonal ET and 7.5% higher WUE. The higher WUE and stable yield under W1 was associated with higher 1000-grain weight (TGW) and harvest index (HI). Among the 3 cultivars, JM22 had 5.9%-8.9% higher yield and 4.2%-9.3% higher WUE than WM8 and HS4399. The higher yield in JM22 was attributed mainly to higher HI and TGW due to increased post-anthesis biomass and deeper seasonal soil water extraction. In conclusion, one-irrigation with a medium-sized spike cultivar JM22 could be a useful strategy to maintain yield and high WUE in extremely late-sown winter wheat at a high seeding rate in the NCP.

Harvesting Mechanical and Thermal Energy by Combining ZnO Nanowires and NiTi Shape Memory Alloy

DOE PAGES

Radousky, Harry; Qian, Fang; An, Yonghao; ...

2017-02-19

In the expanding world of small scale energy harvesting, the ability to combine thermal and mechanical harvesting is growing ever more important. Here, we demonstrate the feasibility of using ZnO nanowires to harvest both mechanical and low-quality thermal energy in simple, scalable devices. These devices were fabricated on kapton films and used ZnO nanowires with the same growth direction to assure alignment of the piezoelectric potentials of all of the wires. Mechanical harvesting from these devices was demonstrated using a periodic application of force, modeling the motion of the human body. Tapping the device from the top of the devicemore » with a wood stick, for example yielded an Open Circuit Voltage (OCV) of 0.2 - 4 V, which is in an ideal range for device applications. In order to demonstrate thermal harvesting from low quality heat sources, a commercially available Nitinol (Ni-Ti alloy) foil was attached to the nanowire piezoelectric device to create a compound thermoelectric. When bent at room temperature and then heated to 50°C, the Nitinol foil was restored to its original flat shape, which yielded an output voltage of nearly 1 V from the ZnO nanowire device.« less

Harvesting Mechanical and Thermal Energy by Combining ZnO Nanowires and NiTi Shape Memory Alloy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Radousky, Harry; Qian, Fang; An, Yonghao

In the expanding world of small scale energy harvesting, the ability to combine thermal and mechanical harvesting is growing ever more important. Here, we demonstrate the feasibility of using ZnO nanowires to harvest both mechanical and low-quality thermal energy in simple, scalable devices. These devices were fabricated on kapton films and used ZnO nanowires with the same growth direction to assure alignment of the piezoelectric potentials of all of the wires. Mechanical harvesting from these devices was demonstrated using a periodic application of force, modeling the motion of the human body. Tapping the device from the top of the devicemore » with a wood stick, for example yielded an Open Circuit Voltage (OCV) of 0.2 - 4 V, which is in an ideal range for device applications. In order to demonstrate thermal harvesting from low quality heat sources, a commercially available Nitinol (Ni-Ti alloy) foil was attached to the nanowire piezoelectric device to create a compound thermoelectric. When bent at room temperature and then heated to 50°C, the Nitinol foil was restored to its original flat shape, which yielded an output voltage of nearly 1 V from the ZnO nanowire device.« less

Impact of variety on cotton yield monitor calibration

USDA-ARS?s Scientific Manuscript database

Public and private research and demonstration efforts are essential to keeping US producers competitive with those in the rest of the world. While modern yield monitors for grain are able to harvest variety and hybrid trials without imposing variety/hybrid-related bias, many reports have indicated t...

Uncertainties in Predicting Rice Yield by Current Crop Models Under a Wide Range of Climatic Conditions

NASA Technical Reports Server (NTRS)

Li, Tao; Hasegawa, Toshihiro; Yin, Xinyou; Zhu, Yan; Boote, Kenneth; Adam, Myriam; Bregaglio, Simone; Buis, Samuel; Confalonieri, Roberto; Fumoto, Tamon;

Lactation persistency as a component trait of the selection index and increase in reliability by using single nucleotide polymorphism in net merit defined as the first five lactation milk yields and herd life.

PubMed

Togashi, K; Hagiya, K; Osawa, T; Nakanishi, T; Yamazaki, T; Nagamine, Y; Lin, C Y; Matsumoto, S; Aihara, M; Hayasaka, K

2012-08-01

We first sought to clarify the effects of discounted rate, survival rate, and lactation persistency as a component trait of the selection index on net merit, defined as the first five lactation milks and herd life (HL) weighted by 1 and 0.389 (currently used in Japan), respectively, in units of genetic standard deviation. Survival rate increased the relative economic importance of later lactation traits and the first five lactation milk yields during the first 120 months from the start of the breeding scheme. In contrast, reliabilities of the estimated breeding value (EBV) in later lactation traits are lower than those of earlier lactation traits. We then sought to clarify the effects of applying single nucleotide polymorphism (SNP) on net merit to improve the reliability of EBV of later lactation traits to maximize their increased economic importance due to increase in survival rate. Net merit, selection accuracy, and HL increased by adding lactation persistency to the selection index whose component traits were only milk yields. Lactation persistency of the second and (especially) third parities contributed to increasing HL while maintaining the first five lactation milk yields compared with the selection index whose only component traits were milk yields. A selection index comprising the first three lactation milk yields and persistency accounted for 99.4% of net merit derived from a selection index whose components were identical to those for net merit. We consider that the selection index comprising the first three lactation milk yields and persistency is a practical method for increasing lifetime milk yield in the absence of data regarding HL. Applying SNP to the second- and third-lactation traits and HL increased net merit and HL by maximizing the increased economic importance of later lactation traits, reducing the effect of first-lactation milk yield on HL (genetic correlation (rG) = -0.006), and by augmenting the effects of the second- and third

Microbial catabolic activities are naturally selected by metabolic energy harvest rate.

PubMed

González-Cabaleiro, Rebeca; Ofiţeru, Irina D; Lema, Juan M; Rodríguez, Jorge

2015-12-01

The fundamental trade-off between yield and rate of energy harvest per unit of substrate has been largely discussed as a main characteristic for microbial established cooperation or competition. In this study, this point is addressed by developing a generalized model that simulates competition between existing and not experimentally reported microbial catabolic activities defined only based on well-known biochemical pathways. No specific microbial physiological adaptations are considered, growth yield is calculated coupled to catabolism energetics and a common maximum biomass-specific catabolism rate (expressed as electron transfer rate) is assumed for all microbial groups. Under this approach, successful microbial metabolisms are predicted in line with experimental observations under the hypothesis of maximum energy harvest rate. Two microbial ecosystems, typically found in wastewater treatment plants, are simulated, namely: (i) the anaerobic fermentation of glucose and (ii) the oxidation and reduction of nitrogen under aerobic autotrophic (nitrification) and anoxic heterotrophic and autotrophic (denitrification) conditions. The experimentally observed cross feeding in glucose fermentation, through multiple intermediate fermentation pathways, towards ultimately methane and carbon dioxide is predicted. Analogously, two-stage nitrification (by ammonium and nitrite oxidizers) is predicted as prevailing over nitrification in one stage. Conversely, denitrification is predicted in one stage (by denitrifiers) as well as anammox (anaerobic ammonium oxidation). The model results suggest that these observations are a direct consequence of the different energy yields per electron transferred at the different steps of the pathways. Overall, our results theoretically support the hypothesis that successful microbial catabolic activities are selected by an overall maximum energy harvest rate.

A novel way to establish fertilization recommendations based on agronomic efficiency and a sustainable yield index for rice crops.

PubMed

Liu, Chuang; Liu, Yi; Li, Zhiguo; Zhang, Guoshi; Chen, Fang

2017-04-24

A simpler approach for establishing fertilizer recommendations for major crops is urgently required to improve the application efficiency of commercial fertilizers in China. To address this need, we developed a method based on field data drawn from the China Program of the International Plant Nutrition Institute (IPNI) rice experiments and investigations carried out in southeastern China during 2001 to 2012. Our results show that, using agronomic efficiencies and a sustainable yield index (SYI), this new method for establishing fertilizer recommendations robustly estimated the mean rice yield (7.6 t/ha) and mean nutrient supply capacities (186, 60, and 96 kg/ha of N, P 2 O 5 , and K 2 O, respectively) of fertilizers in the study region. In addition, there were significant differences in rice yield response, economic cost/benefit ratio, and nutrient-use efficiencies associated with agronomic efficiencies ranked as high, medium and low. Thus, ranking agronomic efficiency could strengthen linear models relating rice yields and SYI. Our results also indicate that the new method provides better recommendations in terms of rice yield, SYI, and profitability than previous methods. Hence, we believe it is an effective approach for improving recommended applications of commercial fertilizers to rice (and potentially other crops).

Weather-based forecasts of California crop yields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lobell, D B; Cahill, K N; Field, C B

2005-09-26

Crop yield forecasts provide useful information to a range of users. Yields for several crops in California are currently forecast based on field surveys and farmer interviews, while for many crops official forecasts do not exist. As broad-scale crop yields are largely dependent on weather, measurements from existing meteorological stations have the potential to provide a reliable, timely, and cost-effective means to anticipate crop yields. We developed weather-based models of state-wide yields for 12 major California crops (wine grapes, lettuce, almonds, strawberries, table grapes, hay, oranges, cotton, tomatoes, walnuts, avocados, and pistachios), and tested their accuracy using cross-validation over themore » 1980-2003 period. Many crops were forecast with high accuracy, as judged by the percent of yield variation explained by the forecast, the number of yields with correctly predicted direction of yield change, or the number of yields with correctly predicted extreme yields. The most successfully modeled crop was almonds, with 81% of yield variance captured by the forecast. Predictions for most crops relied on weather measurements well before harvest time, allowing for lead times that were longer than existing procedures in many cases.« less

Monolithic graded-refractive-index glass-based antireflective coatings. Broadband/omnidirectional light harvesting and self-cleaning characteristics

DOE PAGES

Aytug, Tolga; Lupini, Andrew R.; Jellison, Gerald E.; ...

2015-04-23

The design of multifunctional coatings impact impact the performance of many optical systems and components. Such coatings should be mechanically robust, and combine user-defined optical and wetting functions with scalable fabrication formulations. By taking cues from the properties of some natural biological structures, we report here the formation of low-refractive index antireflective glass films that embody omni-directional optical properties over a wide range of wavelengths, while also possessing specific wetting capabilities. The coatings comprise an interconnected network of nanoscale pores surrounded by a nanostructured silica framework. These structures result from a novel fabrication method that utilizes metastable spinodal phase separationmore » in glass-based materials. The approach not only enables design of surface microstructures with graded-index antireflection characteristics, where the surface reflection is suppressed through optical impedance matching between interfaces, but also facilitates self-cleaning ability through modification of the surface chemistry. Based on near complete elimination of Fresnel reflections (yielding >95% transmission through a single-side coated glass) and corresponding increase in broadband transmission, the fabricated nanostructured surfaces are found to promote a general and an invaluable ~3–7% relative increase in current output of multiple direct/indirect bandgap photovoltaic cells. Moreover, these antireflective surfaces also demonstrate superior resistance against mechanical wear and abrasion. Unlike conventional counterparts, the present antireflective coatings are essentially monolithic, enabling simultaneous realization of graded index anti-reflectivity, self-cleaning capability, and mechanical stability within the same surface. Moreover, the concept represents a fundamental basis for development of advanced coated optical quality products, especially where environmental exposure is required.« less

Evaluation of modern cotton harvest systems on irrigated cotton: harvester performance

USDA-ARS?s Scientific Manuscript database

Picker and stripper harvest systems were evaluated on production-scale irrigated cotton on the High Plains of Texas over three harvest seasons. Observations on harvester performance, including time-in-motion, harvest loss, seed cotton composition, and turnout, were conducted at seven locations with...

Hydrologic resilience of a Canadian Foothills watershed to forest harvest

NASA Astrophysics Data System (ADS)

Goodbrand, Amy; Anderson, Axel

2016-04-01

Recent investigations of long-term hydrometeorological, groundwater, and streamflow data from watersheds on the eastern slopes of the Canadian Rocky Mountains showed the streamflow regime was resilient to forest harvest. These watersheds had low levels of harvest relative to their size and a large area of sparsely vegetated alpine talus slopes and exposed bedrock; an area shown to generate the majority of runoff for streamflow. In contrast, watersheds located in the foothills of the Rocky Mountains are of lower relief and typically have harvestable timber throughout the watershed; therefore, these watersheds may be more sensitive to forest disturbance and have increased potential for streamflow response. This project assesses the hydrologic resilience of an Alberta Foothills watershed to forest harvest using a 23-year dataset from the Tri-Creeks Experimental Watershed (Tri-Creeks). Tri-Creeks has been the site of intensive streamflow, groundwater, snow accumulation, and precipitation observations from 1967 - 1990. During the early 1980s, forestry experiments were conducted to compare the effects of timber harvest and riparian buffers, and the effectiveness of timber harvesting ground rules in protecting fisheries and maintaining water resources within three sub-watersheds: Eunice (16.8 km2; control); Deerlick (15.2 km2; 36% streamside timber removal); and, Wampus (28.3 km2; 37% clear-cut). Statistical analyses were used to compare the pre-and post-harvest ratios of treatment to control sub-watershed runoff for: water year, monthly (April - October), snowmelt peak flow, and low flow (10th percentile streamflow) periods as an assessment of hydrologic resilience to forest harvest. The only significant post-harvest change was an increase in water yield during May at Wampus (Mann-Whitney (MW), p<0.05) and Deerlick (MW, p<0.1) Creeks. The lack of change in snowmelt peak flow timing or magnitude was not expected, particularly in Deerlick, which had 36% streamside timber

[Effect of different fertilization treatments on yield and secondary metabolites of Codonopsis pilosula].

PubMed

Hu, Jia-Dong; Mao, Ge; Zhang, Zhi-Wei; Ma, Cun-de; Liang, Zong-Suo; Xia, Guang-Dong; Dong, Juan-E

2017-08-01

The research studies the effect of different fertilization treatments on yield and accumulation of secondary metabolites of Codonopsis pilosula by using single factor randomized block design, in order to ensure reasonable harvesting time and fertilization ratio, and provide the basis for standardized cultivation of C. pilosula. According to the clustering results, the nitrogen fertilizer benefitted for the improvement of root diameter and biomass of C. pilosula. The phosphate fertilizer could promote the content of C. pilosula polysaccharide. The organic fertilizers could increase the content of lobetyolin. With the time going on, C. pilosula's yield, polysaccharide and ehanol-soluble extracts increased while the content of lobetyolin decreased. According to various factors, October is a more reasonable harvest period. Organic fertilizers are more helpful to the yield and accumulation of secondary metabolites of C. pilosula. Copyright© by the Chinese Pharmaceutical Association.

Rice available to waterfowl in harvested fields in the Sacramento Valley, California

USGS Publications Warehouse

Miller, M.R.; Sharp, D.E.; Gilmer, D.S.; Mulvaney, W.R.

1989-01-01

Rice fields in the Sacramento Valley, California were sampled in 1985 and 1986 to determine the weight of rice seed remaining in the fields immediately after harvest and again after the fields were burned. No significant differences were found between years (P>0.05). The pooled mean was 388 kg/ha in harvested fields and 276 kg/ha in burned fields. These values are less than estimates previously available. The values for harvested fields both years were no different (P>0.05) than values obtained by the U.S. Department of Agriculture (USDA). Surveys of rice fields in December both years showed that most fields were left either harvested (26-32%) or burned (37-40%) through the winter. Fields flooded for duck hunting made up 15% of the total. The proportion of fields plowed by December increased from 14% in 1985 to 22% in 1986. Sixty-three percent of all fields that had been flooded for hunting were drained within two weeks after the end of the hunting season. Harvest yield field size levee type (contour, lasered), straw status (spread, windrowed), harvest date, and rice variety did not affect the quantity of seeds remaining after harvest (P>0.05). One harvester model, the Hardy Harvester, left more rice in fields than did others we tested (P<0.001). Specific management programs are recommended to mitigate annual variation in rice seed availability to waterfowl caused by differences in total hectares grown (15% less in 1986) and in the proportion of fields burned and plowed.

Possible ecosystem impacts of applying maximum sustainable yield policy in food chain models.

PubMed

Ghosh, Bapan; Kar, T K

2013-07-21

This paper describes the possible impacts of maximum sustainable yield (MSY) and maximum sustainable total yield (MSTY) policy in ecosystems. In general it is observed that exploitation at MSY (of single species) or MSTY (of multispecies) level may cause the extinction of several species. In particular, for traditional prey-predator system, fishing under combined harvesting effort at MSTY (if it exists) level may be a sustainable policy, but if MSTY does not exist then it is due to the extinction of the predator species only. In generalist prey-predator system, harvesting of any one of the species at MSY level is always a sustainable policy, but harvesting of both the species at MSTY level may or may not be a sustainable policy. In addition, we have also investigated the MSY and MSTY policy in a traditional tri-trophic and four trophic food chain models. Copyright © 2013 Elsevier Ltd. All rights reserved.

Performance metric comparison study for non-magnetic bi-stable energy harvesters

NASA Astrophysics Data System (ADS)

Udani, Janav P.; Wrigley, Cailin; Arrieta, Andres F.

2017-04-01

Energy harvesting employing non-linear systems offers considerable advantages over linear systems given the broadband resonant response which is favorable for applications involving diverse input vibrations. In this respect, the rich dynamics of bi-stable systems present a promising means for harvesting vibrational energy from ambient sources. Harvesters deriving their bi-stability from thermally induced stresses as opposed to magnetic forces are receiving significant attention as it reduces the need for ancillary components and allows for bio- compatible constructions. However, the design of these bi-stable harvesters still requires further optimization to completely exploit the dynamic behavior of these systems. This study presents a comparison of the harvesting capabilities of non-magnetic, bi-stable composite laminates under variations in the design parameters as evaluated utilizing established power metrics. Energy output characteristics of two bi-stable composite laminate plates with a piezoelectric patch bonded on the top surface are experimentally investigated for variations in the thickness ratio and inertial mass positions for multiple load conditions. A particular design configuration is found to perform better over the entire range of testing conditions which include single and multiple frequency excitation, thus indicating that design optimization over the geometry of the harvester yields robust performance. The experimental analysis further highlights the need for appropriate design guidelines for optimization and holistic performance metrics to account for the range of operational conditions.

Satellite-based monitoring of grassland: assessment of harvest dates and frequency using SAR

NASA Astrophysics Data System (ADS)

Siegmund, R.; Grant, K.; Wagner, M.; Hartmann, S.

2016-10-01

Grasslands are among the largest ecosystems worldwide and according to the FAO they contribute to the livelihoods of more than 800 million people. Harvest dates and frequency can be utilised for an improved estimation of grassland yields. In the presented project a highly automatised methodology for detecting harvest dates and frequency using SARamplitude data was developed based on an amplitude change detection techniques. This was achieved by evaluating spatial statistics over field boundaries provided by the European Integrated Administration and Control System (IACS) to identify changes between pre- and post-harvest acquisitions. The combination of this method with a grassland yield model will result in more reliable and regional-wide numbers of grassland yields. In our contribution we will focus on SAR-remote sensing for monitoring harvest frequencies, discuss the requirements concerning the acquisition system, present the technical approach and analyse the verified results. In terms of the acquisition system a high temporal acquisition rate is required, which is generally met by using SARsatellite constellations providing a revisit time of few days. COSMO-SkyMed data were utilised for the pilot study for developing and prototyping a monitoring system. Subsequently the approach was adapted to the use of the C-Band system Sentinel-1A becoming fully operational with the availability of Sentinal-1B. The study area is situated northeast of Munich, Germany, extending to an area of approx. 40km to 40km and covering major verification sites and in-situ data provided by research farms or continuously surveyed in-situ campaigns. An extended time series of SAR data was collected during the cultivation and vegetation cycles between March 2014 and March 2016. All data were processed and harmonised in a GIS database to be analysed and verified according to corresponding in-situ data.

Correlation Between Precipitation and Crop Yield for Corn and Cotton Produced in Alabama

NASA Technical Reports Server (NTRS)

Hayes, Carol E.; Perkey, Donald J.

1998-01-01

In this study, variations in precipitation during the time of corn silking are compared to Alabama corn yields. Also, this study compares precipitation variations during bloom to Alabama cotton yield. The goal is to obtain mathematical correlations between rainfall during the crop's critical period and the crop amount harvested per acre.

The evolutionary legacy of size-selective harvesting extends from genes to populations

PubMed Central

Uusi-Heikkilä, Silva; Whiteley, Andrew R; Kuparinen, Anna; Matsumura, Shuichi; Venturelli, Paul A; Wolter, Christian; Slate, Jon; Primmer, Craig R; Meinelt, Thomas; Killen, Shaun S; Bierbach, David; Polverino, Giovanni; Ludwig, Arne; Arlinghaus, Robert

2015-01-01

Size-selective harvesting is assumed to alter life histories of exploited fish populations, thereby negatively affecting population productivity, recovery, and yield. However, demonstrating that fisheries-induced phenotypic changes in the wild are at least partly genetically determined has proved notoriously difficult. Moreover, the population-level consequences of fisheries-induced evolution are still being controversially discussed. Using an experimental approach, we found that five generations of size-selective harvesting altered the life histories and behavior, but not the metabolic rate, of wild-origin zebrafish (Danio rerio). Fish adapted to high positively size selective fishing pressure invested more in reproduction, reached a smaller adult body size, and were less explorative and bold. Phenotypic changes seemed subtle but were accompanied by genetic changes in functional loci. Thus, our results provided unambiguous evidence for rapid, harvest-induced phenotypic and evolutionary change when harvesting is intensive and size selective. According to a life-history model, the observed life-history changes elevated population growth rate in harvested conditions, but slowed population recovery under a simulated moratorium. Hence, the evolutionary legacy of size-selective harvesting includes populations that are productive under exploited conditions, but selectively disadvantaged to cope with natural selection pressures that often favor large body size. PMID:26136825

Added-values of high spatiotemporal remote sensing data in crop yield estimation

NASA Astrophysics Data System (ADS)

Gao, F.; Anderson, M. C.

2017-12-01

Timely and accurate estimation of crop yield before harvest is critical for food market and administrative planning. Remote sensing derived parameters have been used for estimating crop yield by using either empirical or crop growth models. The uses of remote sensing vegetation index (VI) in crop yield modeling have been typically evaluated at regional and country scales using coarse spatial resolution (a few hundred to kilo-meters) data or assessed over a small region at field level using moderate resolution spatial resolution data (10-100m). Both data sources have shown great potential in capturing spatial and temporal variability in crop yield. However, the added value of data with both high spatial and temporal resolution data has not been evaluated due to the lack of such data source with routine, global coverage. In recent years, more moderate resolution data have become freely available and data fusion approaches that combine data acquired from different spatial and temporal resolutions have been developed. These make the monitoring crop condition and estimating crop yield at field scale become possible. Here we investigate the added value of the high spatial and temporal VI for describing variability of crop yield. The explanatory ability of crop yield based on high spatial and temporal resolution remote sensing data was evaluated in a rain-fed agricultural area in the U.S. Corn Belt. Results show that the fused Landsat-MODIS (high spatial and temporal) VI explains yield variability better than single data source (Landsat or MODIS alone), with EVI2 performing slightly better than NDVI. The maximum VI describes yield variability better than cumulative VI. Even though VI is effective in explaining yield variability within season, the inter-annual variability is more complex and need additional information (e.g. weather, water use and management). Our findings augment the importance of high spatiotemporal remote sensing data and supports new moderate

Piezoelectric and Semiconducting Ribbon for Flexible Energy Harvesting

DTIC Science & Technology

2012-06-08

ES) 10. SPONSOR/MONITOR’S ACRONYM(S) Space and Naval Warfare Systems Command SPA WAR 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION...rubbers could yield breakthroughs in implantable or wearable energy harvesting systems . Being electromechanically coupled, piezoelectric crystals...ctuator d33 (pm/V) PZT PVDF Quartz Bone PZT > 80% Conversion Efficiency 3333 dk  VdE 2233 Energy 250 25 2.5

Ultrasound as an intervention technology for the sanitation of lettuce harvesting knife

USDA-ARS?s Scientific Manuscript database

Lettuce field-coring and trimming practices are recent industry developments designed to improve fresh-cut processing yield and reduce shipping and waste disposal costs. Studies showed that the harvesting/coring knives used could be potentially contaminated with pathogens by contact with contaminat...

Optimization of Light-Harvesting Pigment Improves Photosynthetic Efficiency1[OPEN

PubMed Central

Jin, Honglei; Li, Mengshu; Duan, Sujuan; Fu, Mei; Dong, Xiaoxiao; Feng, Dongru; Wang, Jinfa

2016-01-01

Maximizing light capture by light-harvesting pigment optimization represents an attractive but challenging strategy to improve photosynthetic efficiency. Here, we report that loss of a previously uncharacterized gene, HIGH PHOTOSYNTHETIC EFFICIENCY1 (HPE1), optimizes light-harvesting pigments, leading to improved photosynthetic efficiency and biomass production. Arabidopsis (Arabidopsis thaliana) hpe1 mutants show faster electron transport and increased contents of carbohydrates. HPE1 encodes a chloroplast protein containing an RNA recognition motif that directly associates with and regulates the splicing of target RNAs of plastid genes. HPE1 also interacts with other plastid RNA-splicing factors, including CAF1 and OTP51, which share common targets with HPE1. Deficiency of HPE1 alters the expression of nucleus-encoded chlorophyll-related genes, probably through plastid-to-nucleus signaling, causing decreased total content of chlorophyll (a+b) in a limited range but increased chlorophyll a/b ratio. Interestingly, this adjustment of light-harvesting pigment reduces antenna size, improves light capture, decreases energy loss, mitigates photodamage, and enhances photosynthetic quantum yield during photosynthesis. Our findings suggest a novel strategy to optimize light-harvesting pigments that improves photosynthetic efficiency and biomass production in higher plants. PMID:27609860

Optimal Harvesting in a Periodic Food Chain Model with Size Structures in Predators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Feng-Qin, E-mail: zhafq@263.net; Liu, Rong; Chen, Yuming, E-mail: ychen@wlu.ca

In this paper, we investigate a periodic food chain model with harvesting, where the predators have size structures and are described by first-order partial differential equations. First, we establish the existence of a unique non-negative solution by using the Banach fixed point theorem. Then, we provide optimality conditions by means of normal cone and adjoint system. Finally, we derive the existence of an optimal strategy by means of Ekeland’s variational principle. Here the objective functional represents the net economic benefit yielded from harvesting.

Water yield following forest-grass-forest transitions

Treesearch

Katherine J. Elliott; Peter V. Caldwell; Steven T. Brantley; Chelcy F. Miniat; James M. Vose; Wayne Swank

2017-01-01

Many currently forested areas in the southern Appalachians were harvested in the early 1900s and cleared for agriculture or pasture, but have since been abandoned and reverted to forest (old-field succession). Land-use and land-cover changes such as these may have altered the timing and quantity of water yield (Q). We examined 80 years of streamflow and vegetation data...

Choosing Between Yeast and Bacterial Expression Systems: Yield Dependent

NASA Technical Reports Server (NTRS)

Miller, Rebecca S.; Malone, Christine C.; Moore, Blake P.; Burk, Melissa; Crawford, Lisa; Karr, Laurel J.; Curreri, Peter A. (Technical Monitor)

2002-01-01

Green fluorescent protein (GFP) is a naturally occurring fluorescent protein isolated from the jellyfish Aequorea victoria. The intrinsic fluorescence of the protein is due to a chromophore located in the center of the molecule. Its usefulness has been established as a marker for gene expression and localization of gene products. GFP has recently been utilized as a model protein for crystallization studies at NASA/MSFC, both in earth-based and in microgravity experiments. Because large quantities of purified protein were needed, the cDNA of GFP was cloned into the Pichia pastoris pPICZ(alpha) C strain, with very little protein secreted into the media. Microscopic analysis prior to harvest showed gigantic green fluorescent yeast, but upon harvesting most protein was degraded. Trial fermentations of GFP cloned into pPICZ A for intracellular expression provided unsatisfactory yield. GFP cloned into E, coli was overexpressed at greater than 150 mg/liter, with purification yields at greater than 100mg/liter.

1971 Oregon timber harvest.

Treesearch

Brian R. Wall

1972-01-01

The 1971 Oregon timber harvest of 9.03 billion board feet was the highest since 1969 when 9.15 billion board feet was harvested. The 1971 total harvest was 13.1 percent above the 1970 figure. Western Oregon's harvest rose 11-5 percent, and eastern Oregon's harvest rose 18.6 percent.

Deep rooting conferred by DEEPER ROOTING 1 enhances rice yield in paddy fields.

PubMed

Arai-Sanoh, Yumiko; Takai, Toshiyuki; Yoshinaga, Satoshi; Nakano, Hiroshi; Kojima, Mikiko; Sakakibara, Hitoshi; Kondo, Motohiko; Uga, Yusaku

2014-07-03

To clarify the effect of deep rooting on grain yield in rice (Oryza sativa L.) in an irrigated paddy field with or without fertilizer, we used the shallow-rooting IR64 and the deep-rooting Dro1-NIL (a near-isogenic line homozygous for the Kinandang Patong allele of DEEPER ROOTING 1 (DRO1) in the IR64 genetic background). Although total root length was similar in both lines, more roots were distributed within the lower soil layer of the paddy field in Dro1-NIL than in IR64, irrespective of fertilizer treatment. At maturity, Dro1-NIL showed approximately 10% higher grain yield than IR64, irrespective of fertilizer treatment. Higher grain yield of Dro1-NIL was mainly due to the increased 1000-kernel weight and increased percentage of ripened grains, which resulted in a higher harvest index. After heading, the uptake of nitrogen from soil and leaf nitrogen concentration were higher in Dro1-NIL than in IR64. At the mid-grain-filling stage, Dro1-NIL maintained higher cytokinin fluxes from roots to shoots than IR64. These results suggest that deep rooting by DRO1 enhances nitrogen uptake and cytokinin fluxes at late stages, resulting in better grain filling in Dro1-NIL in a paddy field in this study.

Harvest discrimination of pomegranate fruit: postharvest quality changes and relationships between instrumental and sensory attributes during shelf life.

PubMed

Fawole, Olaniyi Amos; Opara, Umezuruike Linus

2013-08-01

Harvest maturity discrimination was carried out for "Ruby" pomegranate cultivar in simulated handling conditions for long distant supply chains. Fruit were harvested at 3 different maturities along days after full bloom (DAFB); Harvest 1 (H1) at 133 DAFB, H2 at 143 DAFB, and H3 at 157 DAFB. The effects of harvest maturity and storage duration on fruit quality attributes during a 6-wk period of cold storage (5°C, 95% RH) and subsequent 5 d of shelf life (20°C, 75% RH) were investigated. Instrumental evaluation of aril color, juice content, juice absorbance (520 nm), total soluble solids (TSS), pH, titratable acids (TA), and phytochemical components including total phenolics, flavonoids, and anthocyanins were carried out. Textural properties of arils which included hardness, toughness, bioyield point, and Young's modulus were also investigated. During the shelf life period, arils from individual fruit were rated by a trained sensory panel based on appearance, taste, and texture. Relationships between the instrumental and descriptive sensory data were explored and fruit harvest maturities were discriminated using discriminant analysis. Among the attributes evaluated, TSS : TA, sweet taste, and the CIE hue angle (h°) were the most decisive attributes distinguishing the harvest maturities. The optimum time for harvesting was at 143 DAFB (H2) when fruit TSS : TA ratio was > 55, which coincided with significantly higher rating for sweet taste in fruit at H2 than at H1 and H3 during shelf life. The harvest index proposed in the current study could be used as a guide to establish a reliable harvest maturity index to assist in assuring fruit quality in consideration of long supply chains for the investigated cultivar. © 2013 Institute of Food Technologists®

Optimal harvesting of a stochastic delay tri-trophic food-chain model with Lévy jumps

NASA Astrophysics Data System (ADS)

Qiu, Hong; Deng, Wenmin

2018-02-01

In this paper, the optimal harvesting of a stochastic delay tri-trophic food-chain model with Lévy jumps is considered. We introduce two kinds of environmental perturbations in this model. One is called white noise which is continuous and is described by a stochastic integral with respect to the standard Brownian motion. And the other one is jumping noise which is modeled by a Lévy process. Under some mild assumptions, the critical values between extinction and persistent in the mean of each species are established. The sufficient and necessary criteria for the existence of optimal harvesting policy are established and the optimal harvesting effort and the maximum of sustainable yield are also obtained. We utilize the ergodic method to discuss the optimal harvesting problem. The results show that white noises and Lévy noises significantly affect the optimal harvesting policy while time delays is harmless for the optimal harvesting strategy in some cases. At last, some numerical examples are introduced to show the validity of our results.

Harvesting

Treesearch

John R. Jones; Wayne D. Shepperd

1985-01-01

Harvesting is the removal of produce from the forest for utilization. It includes cutting, any further initial processing, such as topping and trimming, and extraction (Ford-Robertson 1971). Commercial intermediate cutting, such as commercial thinning, as well as regeneration cutting are included. Harvesting and the income that it produces sometimes is regarded as an...

Harvest management effects on "Tifton 44" Bermundagrass phosphorous removal and nutritive value

USDA-ARS?s Scientific Manuscript database

Production of bermudagrass [Cynodon dactylon (L.) Pers.] hay to manage manure nutrients may differ from production of hay intended for livestock consumption. This 3-yr study (2005-2007) determined harvest management effects on dry matter (DM) yield, P uptake, and forage nutritive value in ‘Tifton 44...

Identification of potentially high yielding irradiated cassava ‘Gajah’ genotype with different geographic coordinates

NASA Astrophysics Data System (ADS)

Subekti, I.; Khumaida, N.; Ardie, SW

2017-01-01

Cassava is one of the main and important carbohydrate producing crops in Indonesia. Thus cassava production and its tuber quality need to be improved. ‘Gajah’ genotype is a local genotypes cassava from East Kalimantan, has high potential yield (> 60 ton Ha-1). However, the harvest time of this genotype is quite long (>= 12 months). The objective of this research was to identify the high yielding cassava mutants from the gamma rays irradiated ‘Gajah’ genotype at M1V3 population and potential yield at different location. Several putative cassava mutants (12 mutants) were planted in Cikabayan Experimental Field, IPB from March 2015 to March 2016 and the yields compared with the same genotype grown at different location by seeing its coordinates to observe the potential yield. Our result showed that the fresh tuber weight per plant of some putative mutants could reach more than 8 kg (yield potential of 64 ton Ha-1). The harvested tubers also had sweet flavor, although the tubers of some putative mutants were bitter. Based on previous research study, the different geographic coordinate has resulted variability on fresh tuber yield. It seems that it needs to observe the stability of ‘Gajah’- irradiated mutants in several location in Java Island.

1972 Oregon timber harvest.

Treesearch

J.D. Jr. Lloyd

1973-01-01

The 1972 Oregon timber harvest of 9.6 billion board feet was 602 million board feet (6.7 percent) above the 1971 harvest. Western Oregon's harvest rose 8 percent and eastern Oregon's harvest rose 2 percent.

Seed yield, development, and variation in diverse poa pratensis accessions

USDA-ARS?s Scientific Manuscript database

Post harvest residue removal is critical for continued high seed production of Kentucky bluegrass (Poa pratensis L.). Previous work showed some accessions have little or no yield reduction with mechanical residue removal compared with the controversial practice of open field burning. Using 10 of t...

Developing recreational harvest regulations for an unexploited lake trout population

USGS Publications Warehouse

Lenker, Melissa A; Weidel, Brian C.; Jensen, Olaf P.; Solomon, Christopher T.

2016-01-01

Developing fishing regulations for previously unexploited populations presents numerous challenges, many of which stem from a scarcity of baseline information about abundance, population productivity, and expected angling pressure. We used simulation models to test the effect of six management strategies (catch and release; trophy, minimum, and maximum length limits; and protected and exploited slot length limits) on an unexploited population of Lake Trout Salvelinus namaycush in Follensby Pond, a 393-ha lake located in New York State’s Adirondack Park. We combined field and literature data and mark–recapture abundance estimates to parameterize an age-structured population model and used the model to assess the effects of each management strategy on abundance, catch per unit effort (CPUE), and harvest over a range of angler effort (0–2,000 angler-days/year). Lake Trout density (3.5 fish/ha for fish ≥ age 13, the estimated age at maturity) was similar to densities observed in other unexploited systems, but growth rate was relatively slow. Maximum harvest occurred at levels of effort ≤ 1,000 angler-days/year in all the scenarios considered. Regulations that permitted harvest of large postmaturation fish, such as New York’s standard Lake Trout minimum size limit or a trophy size limit, resulted in low harvest and high angler CPUE. Regulations that permitted harvest of small and sometimes immature fish, such as a protected slot or maximum size limit, allowed high harvest but resulted in low angler CPUE and produced rapid declines in harvest with increases in effort beyond the effort consistent with maximum yield. Management agencies can use these results to match regulations to management goals and to assess the risks of different management options for unexploited Lake Trout populations and other fish species with similar life history traits.

Knockdown of an inflorescence meristem-specific cytokinin oxidase - OsCKX2 in rice reduces yield penalty under salinity stress condition.

PubMed

Joshi, Rohit; Sahoo, Khirod Kumar; Tripathi, Amit Kumar; Kumar, Ritesh; Gupta, Brijesh Kumar; Pareek, Ashwani; Singla-Pareek, Sneh Lata

2018-05-01

Cytokinins play a significant role in determining grain yield in plants. Cytokinin oxidases catalyse irreversible degradation of cytokinins and hence modulate cellular cytokinin levels. Here, we studied the role of an inflorescence meristem-specific rice cytokinin oxidase - OsCKX2 - in reducing yield penalty under salinity stress conditions. We utilized an RNAi-based approach to study the function of OsCKX2 in maintaining grain yield under salinity stress condition. Ultra-performance liquid chromatography-based estimation revealed a significant increase in cytokinins in the inflorescence meristem of OsCKX2-knockdown plants. To determine if there exists a correlation between OsCKX2 levels and yield under salinity stress condition, we assessed the growth, physiology and grain yield of OsCKX2-knockdown plants vis-à-vis the wild type. OsCKX2-knockdown plants showed better vegetative growth, higher relative water content and photosynthetic efficiency and reduced electrolyte leakage as compared with the wild type under salinity stress. Importantly, we found a negative correlation between OsCKX2 expression and plant productivity as evident by assessment of agronomical parameters such as panicle branching, filled grains per plant and harvest index both under control and salinity stress conditions. These results suggest that OsCKX2, via controlling cytokinin levels, regulates floral primordial activity modulating rice grain yield under normal as well as abiotic stress conditions. © 2017 John Wiley & Sons Ltd.

1975 Oregon timber harvest.

Treesearch

J.D. Jr. Lloyd

1976-01-01

The 1975 Oregon timber harvest declined to its lowest level since 1961 with a harvest of 7.37 billion board feet, 991 million board feet (11.9 percent) below the 1974 harvest. The harvest was down in both western Oregon (823 million board feet, 13.2 percent) and eastern Oregon (168 million board feet, 7.7 percent). For the first time since 1961, the harvest on private...

Estimating regional wheat yield from the shape of decreasing curves of green area index temporal profiles retrieved from MODIS data

NASA Astrophysics Data System (ADS)

Kouadio, Louis; Duveiller, Grégory; Djaby, Bakary; El Jarroudi, Moussa; Defourny, Pierre; Tychon, Bernard

2012-08-01

Earth observation data, owing to their synoptic, timely and repetitive coverage, have been recognized as a valuable tool for crop monitoring at different levels. At the field level, the close correlation between green leaf area (GLA) during maturation and grain yield in wheat revealed that the onset and rate of senescence appeared to be important factors for determining wheat grain yield. Our study sought to explore a simple approach for wheat yield forecasting at the regional level, based on metrics derived from the senescence phase of the green area index (GAI) retrieved from remote sensing data. This study took advantage of recent methodological improvements in which imagery with high revisit frequency but coarse spatial resolution can be exploited to derive crop-specific GAI time series by selecting pixels whose ground-projected instantaneous field of view is dominated by the target crop: winter wheat. A logistic function was used to characterize the GAI senescence phase and derive the metrics of this phase. Four regression-based models involving these metrics (i.e., the maximum GAI value, the senescence rate and the thermal time taken to reach 50% of the green surface in the senescent phase) were related to official wheat yield data. The performances of such models at this regional scale showed that final yield could be estimated with an RMSE of 0.57 ton ha-1, representing about 7% as relative RMSE. Such an approach may be considered as a first yield estimate that could be performed in order to provide better integrated yield assessments in operational systems.

Estimating Sustainable Live-Coral Harvest at Kamiali Wildlife Management Area, Papua New Guinea.

PubMed

Longenecker, Ken; Bolick, Holly; Langston, Ross

2015-01-01

Live coral is harvested throughout the Indo-West Pacific to make lime, used in the consumption of the world's fourth-most consumed drug, betel nut. Coral harvesting is an environmental concern; however, because lime-making is one of the few sources of income in some areas of Papua New Guinea (PNG), the practice is unlikely to stop. To better manage coral harvest, we used standard fishery-yield methods to generate sustainable-harvest guidelines for corymbose Acropora species found on the reef flat and crest at Lababia, PNG. We constructed a yield curve (weight-specific net annual-dry-weight production) by: 1) describing the allometric relationship between colony size and dry weight, and using that relationship to estimate the dry weight of Acropora colonies in situ; 2) estimating annual growth of Acropora colonies by estimating in situ, and describing the relationship between, colony dry weight at the beginning and end of one year; and 3) conducting belt-transect surveys to describe weight-frequencies and ultimately to predict annual weight change per square meter for each weight class. Reef habitat covers a total 2,467,550 m2 at Lababia and produces an estimated 248,397 kg/y (dry weight) of corymbose Acropora, of which 203,897 kg is produced on the reef flat/crest. We conservatively estimate that 30,706.6 kg of whole, dry, corymbose, Acropora can be sustainably harvested from the reef flat/crest habitat each year provided each culled colony weighs at least 1805 g when dry (or is at least 46 cm along its major axis). Artisanal lime-makers convert 24.8% of whole-colony weight into marketable lime, thus we estimate 7615.2 g of lime can be sustainably produced annually from corymbose Acropora. This value incorporates several safety margins, and should lead to proper management of live coral harvest. Importantly, the guideline recognizes village rights to exploit its marine resources, is consistent with village needs for income, and balances an equally strong village

Post-harvest physiology

USDA-ARS?s Scientific Manuscript database

Weather and management constraints, as well as the intended use of the harvested forage, all influence the forage harvest system selected by the producer. Generally, maximum retention of dry matter from harvested forage crops is achieved at moistures intermediate between the standing fresh crop and ...

Rain-induced spring wheat harvest losses

NASA Technical Reports Server (NTRS)

Bauer, A.; Black, A. L. (Principal Investigator)

1983-01-01

When rain or a combination of rain and high humidity delay wheat harvest, losses can occur in grain yield and/or grain quality. Yield losses can result from shattering, from reduction in test weight, and in the case of windrowed grain, from rooting of sprouting grain at the soil: windrow contact. Losses in grain quality can result from reduction in test weight and from sprouting. Sprouting causes a degradation of grain proteins and starches, hence flour quality is reduced, and the grain price deteriorates to the value of feed grain. Although losses in grain yield and quality are rain-induced, these losses do not necessarily occur because a standing or windrowed crop is wetted by rain. Spike water concentration in hard red spring wheat must be increased to about 45-49% before sprouting is initiated in grain that has overcome dormancy. The time required to overcome this dormancy after the cultivar has dried to 12 to 14% water concentration differs with hard red spring cultivars. The effect of rain on threshing-ready standing and windrowed hard red spring wheat grain yeild and quality was evaluated. A goal was to develop the capability to forecast the extent of expected loss of grain yield and quality from specific climatic events that delay threshing.

Broadband pendulum energy harvester

NASA Astrophysics Data System (ADS)

Liang, Changwei; Wu, You; Zuo, Lei

2016-09-01

A novel electromagnetic pendulum energy harvester with mechanical motion rectifier (MMR) is proposed and investigated in this paper. MMR is a mechanism which rectifies the bidirectional swing motion of the pendulum into unidirectional rotation of the generator by using two one-way clutches in the gear system. In this paper, two prototypes of pendulum energy harvester with MMR and without MMR are designed and fabricated. The dynamic model of the proposed MMR pendulum energy harvester is established by considering the engagement and disengagement of the one way clutches. The simulation results show that the proposed MMR pendulum energy harvester has a larger output power at high frequencies comparing with non-MMR pendulum energy harvester which benefits from the disengagement of one-way clutch during pendulum vibration. Moreover, the proposed MMR pendulum energy harvester is broadband compare with non-MMR pendulum energy harvester, especially when the equivalent inertia is large. An experiment is also conducted to compare the energy harvesting performance of these two prototypes. A flywheel is attached at the end of the generator to make the disengagement more significant. The experiment results also verify that MMR pendulum energy harvester is broadband and has a larger output power at high frequency over the non-MMR pendulum energy harvester.

Predicting paddlefish roe yields using an extension of the Beverton–Holt equilibrium yield-per-recruit model

USGS Publications Warehouse

Colvin, M.E.; Bettoli, Phillip William; Scholten, G.D.

2013-01-01

Equilibrium yield models predict the total biomass removed from an exploited stock; however, traditional yield models must be modified to simulate roe yields because a linear relationship between age (or length) and mature ovary weight does not typically exist. We extended the traditional Beverton-Holt equilibrium yield model to predict roe yields of Paddlefish Polyodon spathula in Kentucky Lake, Tennessee-Kentucky, as a function of varying conditional fishing mortality rates (10-70%), conditional natural mortality rates (cm; 9% and 18%), and four minimum size limits ranging from 864 to 1,016mm eye-to-fork length. These results were then compared to a biomass-based yield assessment. Analysis of roe yields indicated the potential for growth overfishing at lower exploitation rates and smaller minimum length limits than were suggested by the biomass-based assessment. Patterns of biomass and roe yields in relation to exploitation rates were similar regardless of the simulated value of cm, thus indicating that the results were insensitive to changes in cm. Our results also suggested that higher minimum length limits would increase roe yield and reduce the potential for growth overfishing and recruitment overfishing at the simulated cm values. Biomass-based equilibrium yield assessments are commonly used to assess the effects of harvest on other caviar-based fisheries; however, our analysis demonstrates that such assessments likely underestimate the probability and severity of growth overfishing when roe is targeted. Therefore, equilibrium roe yield-per-recruit models should also be considered to guide the management process for caviar-producing fish species.

Yield of Unthinned Yellow-Poplar

Treesearch

Donald E. Beck; Lino Della-Bianca

1970-01-01

Cubic-foot and board-foot yields of unthinned yellow-poplar (Liriodendron Tulipiferi L.) stands are described in relation to stand age, site index, and number of trees per acre. The yield tables are based on analysis of diameter distributions and height-diameter relationships obtained from 141 natural, unthinned yellow-poplar stands in the...

Estimation of dew yield from radiative condensers by means of an energy balance model

NASA Astrophysics Data System (ADS)

Maestre-Valero, J. F.; Ragab, R.; Martínez-Alvarez, V.; Baille, A.

2012-08-01

SummaryThis paper presents an energy balance modelling approach to predict the nightly water yield and the surface temperature (Tf) of two passive radiative dew condensers (RDCs) tilted 30° from horizontal. One was fitted with a white hydrophilic polyethylene foil recommended for dew harvest and the other with a black polyethylene foil widely used in horticulture. The model was validated in south-eastern Spain by comparing the simulation outputs with field measurements of Tf and dew yield. The results indicate that the model is robust and accurate in reproducing the behaviour of the two RDCs, especially in what refers to Tf, whose estimates were very close to the observations. The results were somewhat less precise for dew yield, with a larger scatter around the 1:1 relationship. A sensitivity analysis showed that the simulated dew yield was highly sensitive to changes in relative humidity and downward longwave radiation. The proposed approach provides a useful tool to water managers for quantifying the amount of dew that could be harvested as a valuable water resource in arid, semiarid and water stressed regions.

Hydrologic and climatic changes in three small watersheds after timber harvest.

Treesearch

W.B. Fowler; J.D. Helvey; E.N. Felix

1987-01-01

No significant increases in annual water yield were shown for three small watersheds in northeastern Oregon after shelterwood cutting (30-percent canopy removal, 50-percent basal area removal) and clearcutting. Average maximum air temperature increased after harvest and average minimum air temperature decreased by up to 2.6 °C. Both maximum and minimum water...

Effect of Harvesting Stage on Sweet Sorghum (Sorghum bicolor L.) Genotypes in Western Kenya

PubMed Central

Owuoche, James O.; Oyoo, Maurice E.; Cheruiyot, Erick; Mulianga, Betty

2017-01-01

Harvesting stage of sweet sorghum (Sorghum bicolor L. Moench) cane is an important aspect in the content of sugar for production of industrial alcohol. Four sweet sorghum genotypes were evaluated for harvesting stage in a randomized complete block design. In order to determine sorghum harvest growth stage for bioethanol production, sorghum canes were harvested at intervals of seven days after anthesis. The genotypes were evaluated at different stages of development for maximum production of bioethanol from flowering to physiological maturity. The canes were crushed and juice fermented to produce ethanol. Measurements of chlorophyll were taken at various stages as well as panicles from the harvested canes. Dried kernels at 14% moisture content were also weighed at various stages. Chlorophyll, grain weight, absolute ethanol volume, juice volume, cane yield, and brix showed significant (p = 0.05) differences for genotypes as well as the stages of harvesting. Results from this study showed that harvesting sweet sorghum at stages IV and V (104 to 117 days after planting) would be appropriate for production of kernels and ethanol. EUSS10 has the highest ethanol potential (1062.78 l ha−1) due to excellent juice volume (22976.9 l ha−1) and EUSS11 (985.26 l ha−1) due to its high brix (16.21). PMID:28255577

Electrokinetic Analysis of Energy Harvest from Natural Salt Gradients in Nanochannels.

PubMed

He, Yuhui; Huang, Zhuo; Chen, Bowei; Tsutsui, Makusu; Shui Miao, Xiang; Taniguchi, Masateru

2017-10-13

The Gibbs free energy released during the mixing of river and sea water has been illustrated as a promising source of clean and renewable energy. Reverse electrodialysis (RED) is one major strategy to gain electrical power from this natural salinity, and recently by utilizing nanochannels a novel mode of this approach has shown improved power density and energy converting efficiency. In this work, we carry out an electrokinetic analysis of the work extracted from RED in the nanochannels. First, we outline the exclusion potential effect induced by the inhomogeneous distribution of extra-counterions along the channel axis. This effect is unique in nanochannel RED and how to optimize it for energy harvesting is the central topic of this work. We then discuss two important indexes of performance, which are the output power density and the energy converting efficiency, and their dependence on the nanochannel parameters such as channel material and geometry. In order to yield maximized output electrical power, we propose a device design by stepwise usage of the saline bias, and the lengths of the nanochannels are optimized to achieve the best trade-off between the input thermal power and the energy converting efficiency.

Switchgrass harvest time management can impact biomass yield and nutrient content

USDA-ARS?s Scientific Manuscript database

Switchgrass (Panicum virgatum L.) is a dedicated energy crop native to much of North America. While high-biomass yield is of significant importance for the development of switchgrass as a bioenergy crop, nutrient content in the biomass as it relates to biofuel conversion efficiency is also critical...

Strong Coupling of Localized Surface Plasmons to Excitons in Light-Harvesting Complexes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsargorodska, Anna; Cartron, Michaël L.; Vasilev, Cvetelin

Gold nanostructure arrays exhibit surface plasmon resonances that split after attaching light harvesting complexes 1 and 2 (LH1 and LH2) from purple bacteria. The splitting is attributed to strong coupling between the localized surface plasmon resonances and excitons in the light-harvesting complexes. Wild-type and mutant LH1 and LH2 from Rhodobacter sphaeroides containing different carotenoids yield different splitting energies, demonstrating that the coupling mechanism is sensitive to the electronic states in the light harvesting complexes. Plasmon–exciton coupling models reveal different coupling strengths depending on the molecular organization and the protein coverage, consistent with strong coupling. Strong coupling was also observed formore » self-assembling polypeptide maquettes that contain only chlorins. However, it is not observed for monolayers of bacteriochlorophyll, indicating that strong plasmon–exciton coupling is sensitive to the specific presentation of the pigment molecules.« less

Strong Coupling of Localized Surface Plasmons to Excitons in Light-Harvesting Complexes

DOE PAGES

Tsargorodska, Anna; Cartron, Michaël L.; Vasilev, Cvetelin; ...

2016-09-30

Gold nanostructure arrays exhibit surface plasmon resonances that split after attaching light harvesting complexes 1 and 2 (LH1 and LH2) from purple bacteria. The splitting is attributed to strong coupling between the localized surface plasmon resonances and excitons in the light-harvesting complexes. Wild-type and mutant LH1 and LH2 from Rhodobacter sphaeroides containing different carotenoids yield different splitting energies, demonstrating that the coupling mechanism is sensitive to the electronic states in the light harvesting complexes. Plasmon–exciton coupling models reveal different coupling strengths depending on the molecular organization and the protein coverage, consistent with strong coupling. Strong coupling was also observed formore » self-assembling polypeptide maquettes that contain only chlorins. However, it is not observed for monolayers of bacteriochlorophyll, indicating that strong plasmon–exciton coupling is sensitive to the specific presentation of the pigment molecules.« less

Enhanced Harvesting of Chlorella vulgaris Using Combined Flocculants.

PubMed

Ma, Xiaochen; Zheng, Hongli; Zhou, Wenguang; Liu, Yuhuan; Chen, Paul; Ruan, Roger

2016-10-01

In this study, a novel flocculation strategy for harvesting Chlorella vulgaris with combined flocculants, poly (γ-glutamic acid) (γ-PGA) and calcium oxide (CaO), has been developed. The effect of flocculant dosage, the order of flocculant addition, mixing speed, and growth stage on the harvesting efficiency was evaluated. Results showed that the flocculation using combined flocculants significantly decreases the flocculant dosage and settling time compared with control. It was also found that CaO and γ-PGA influenced microalgal flocculation by changing the zeta potential of cells and pH of microalgal suspension. The most suitable order of flocculant addition was CaO first and then γ-PGA. The optimal mixing speed was 200 rpm for 0.5 min, followed by 50 rpm for another 4.5 min for CaO and γ-PGA with the highest flocculation efficiency of 95 % and a concentration factor of 35.5. The biomass concentration and lipid yield of the culture reusing the flocculated medium were similar to those when a fresh medium was used. Overall, the proposed method requires low energy input, alleviates biomass and water contamination, and reduces utilization of water resources and is feasible for harvesting C. vulgaris for biofuel and other bio-based chemical production.

Subsequent donation requests among 2472 unrelated hematopoietic progenitor cell donors are associated with bone marrow harvest

PubMed Central

Lown, Robert N.; Tulpule, Sameer; Russell, Nigel H.; Craddock, Charles F.; Roest, Rochelle; Madrigal, J. Alejandro; Shaw, Bronwen E.

2013-01-01

Approximately 1 in 20 unrelated donors are asked to make a second donation of hematopoietic progenitor cells, the majority for the same patient. Anthony Nolan undertook a study of subsequent hematopoietic progenitor cell donations made by its donors from 2005 to 2011, with the aims of predicting those donors more likely to be called for a second donation, assessing rates of serious adverse reactions and examining harvest yields. This was not a study of factors predictive of second allografts. During the study period 2591 donations were made, of which 120 (4.6%) were subsequent donations. The median time between donations was 179 days (range, 21–4016). Indications for a second allogeneic transplant included primary graft failure (11.7%), secondary graft failure (53.2%), relapse (30.6%) and others (1.8%). On multivariate analysis, bone marrow harvest at first donation was associated with subsequent donation requests (odds ratio 2.00, P=0.001). The rate of serious adverse reactions in donors making a subsequent donation appeared greater than the rate in those making a first donation (relative risk=3.29, P=0.005). Harvest yields per kilogram recipient body weight were equivalent between donations, although females appeared to have a lower yield at the subsequent donation. Knowledge of these factors will help unrelated donor registries to counsel their donors. PMID:23812935

Assimilating Remote Sensing Observations of Leaf Area Index and Soil Moisture for Wheat Yield Estimates: An Observing System Simulation Experiment

NASA Technical Reports Server (NTRS)

Nearing, Grey S.; Crow, Wade T.; Thorp, Kelly R.; Moran, Mary S.; Reichle, Rolf H.; Gupta, Hoshin V.

2012-01-01

Observing system simulation experiments were used to investigate ensemble Bayesian state updating data assimilation of observations of leaf area index (LAI) and soil moisture (theta) for the purpose of improving single-season wheat yield estimates with the Decision Support System for Agrotechnology Transfer (DSSAT) CropSim-Ceres model. Assimilation was conducted in an energy-limited environment and a water-limited environment. Modeling uncertainty was prescribed to weather inputs, soil parameters and initial conditions, and cultivar parameters and through perturbations to model state transition equations. The ensemble Kalman filter and the sequential importance resampling filter were tested for the ability to attenuate effects of these types of uncertainty on yield estimates. LAI and theta observations were synthesized according to characteristics of existing remote sensing data, and effects of observation error were tested. Results indicate that the potential for assimilation to improve end-of-season yield estimates is low. Limitations are due to a lack of root zone soil moisture information, error in LAI observations, and a lack of correlation between leaf and grain growth.

Rx for low cash yields.

PubMed

Tobe, Chris

2003-10-01

Certain strategies can offer not-for-profit hospitals potentially greater investment yields while maintaining stability and principal safety. Treasury inflation-indexed securities can offer good returns, low volatility, and inflation protection. "Enhanced cash" strategies offer liquidity and help to preserve capital. Stable value "wrappers" allow hospitals to pursue higher-yielding fixed-income securities without an increase in volatility.

Corn Belt soil carbon and macronutrient budgets with projected sustainable stover harvest

USGS Publications Warehouse

Tan, Zhengxi; Liu, Shu-Guang

2015-01-01

Corn (Zea mays L.) stover has been identified as a prime feedstock for biofuel production in the U.S. Corn Belt because of its perceived abundance and availability, but long-term stover harvest effects on regional nutrient budgets have not been evaluated. We defined the minimum stover requirement (MSR) to maintain current soil organic carbon levels and then estimated current and future soil carbon (C), nitrogen (N), phosphorus (P), and potassium (K) budgets for various stover harvest scenarios. Analyses for 2006 through 2010 across the entire Corn Belt indicated that currently, 28 Tg or 1.6 Mg ha−1 of stover could be sustainably harvested from 17.95 million hectares (Mha) with N, P, and K removal of 113, 26, and 47 kg ha−1, respectively, and C removal for that period was estimated to be 4.55 Mg C ha−1. Assuming continued yield increases and a planted area of 26.74 Mha in 2050, 77.4 Tg stover (or 2.4 Mg ha−1) could be sustainably harvested with N, P, and K removal of 177, 37, and 72 kg ha−1, respectively, along with C removal of ∼6.57 Mg C ha−1. Although there would be significant variation across the region, harvesting only the excess over the MSR under current fertilization rates would result in a small depletion of soil N (−5 ± 27 kg ha−1) and K (−20 ± 31 kg ha−1) and a moderate surplus of P (36 ± 18 kg ha−1). Our 2050 projections based on continuing to keep the MSR, but having higher yields indicate that soil N and K deficits would become larger, thus emphasize the importance of balancing soil nutrient supply with crop residue removal.

[Effects of deep plowing and mulch in fallow period on soil water and yield of wheat in dryland].

PubMed

Deng, Yan; Gao, Zhi-Qiang; Sun, Min; Zhao, Wei-Feng; Zhao, Hong-Mei; Li, Qing

2014-01-01

A field test was carried out in Qiujialing Village, Wenxi, Shanxi from 2009 to 2011 to study the soil water movement of 0-300 cm layer, yield formation and water use efficiency (WUE) of wheat with deep plowing and mulching the whole ground immediately (no mulch as control) 15 days and 45 days after harvest. The results indicated that deep plowing and mulch in fallow period could improve soil water storage of the 100-180 cm layer before sowing, the soil water storage efficiency in fallow period, and soil water storage from pre-wintering stage to booting stage. Compared with deep plowing 15 days after wheat harvest, deep plowing 45 days after wheat harvest did better in improving soil water storage and water use efficiency, as well as ear number and yield, which was more conducive in the year with more precipitation. Generally, deep plowing and mulching after raining during fallow period could benefit the soil water storage and conservation, thus would be helpful to improve wheat yield in dryland.

Ethanol yields and cell wall properties in divergently bred switchgrass genotypes

USDA-ARS?s Scientific Manuscript database

Genetic modification of herbaceous plant cell walls to increase biofuels yields from harvested biomass is a primary bioenergy research goal. The focus of much of this research has been on cell wall lignin concentration. Using switchgrass genotypes developed by divergent breeding for ruminant diges...

Studies on optimum harvest time for hybrid rice seed.

PubMed

Fu, Hong; Cao, Dong-Dong; Hu, Wei-Min; Guan, Ya-Jing; Fu, Yu-Ying; Fang, Yong-Feng; Hu, Jin

2017-03-01

Timely harvest is critical for hybrid rice to achieve maximum seed viability, vigor and yield. However, how to predict the optimum harvest time has been rarely reported so far. The seed vigor of Zhuliangyou 06 (ZLY06) increased and reached the highest level at 20 days after pollination (DAP), when seed moisture content had a lower value, which was maintained until final seed maturation. For Chunyou 84 (CY84), seed vigor, fresh and dry weight had relatively high values at 25 DAP, when seed moisture content reached the lowest value and changed slightly from 25 to 55 DAP. In both hybrid rice varieties, seed glume chlorophyll content declined rapidly from 10 to 30 DAP and remained at a very low level after 35 DAP. Starch content exhibited an increasing trend during seed maturation, while both soluble sugar content and amylase activity decreased significantly at the early stages of seed development. Moreover, correlation analyses showed that seed dry weight, starch content and superoxide dismutase activity were significantly positively correlated with seed vigor. In contrast, chlorophyll content, moisture content, soluble sugar, soluble protein, abscisic acid, gibberellin content, electrical conductivity, catalase and ascorbate peroxidase activities were significantly negatively correlated with seed vigor. Physiological and biochemical parameters were obviously more closely related with seed vigor than with seed germinability during seed development. Seed vigor could be better used as a comprehensive factor to predict the optimum seed harvest time. It is suggested that for ZLY06 seeds could be harvested as early as 20 DAP, whereas for CY84 the earliest optimum harvest time was 25 DAP. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Energy Harvesting & Recapture from Human Subjects: Dual-Stage MEMS Cantilever Energy Harvester

DTIC Science & Technology

2015-03-01

15 Figure 5. (a) In-plane overlap-varying capacitive harvester, (b) In-plane gap-closing capacitive harvester, (c) Out -of-plane gap-closing...capacitive harvester, (c) Out -of-plane gap-closing capacitive harvester [1] The two-way arrows in each subpart of Figure 5 indicate the shuttle’s direction...are compatible with other wafer -based technologies. Bismuth Telluride (Bi2Te3), a common Seebeck thermoelectric material, is able to be processed

Detection of meteorological extreme effect on historical crop yield anomaly

NASA Astrophysics Data System (ADS)

Kim, W.; Iizumi, T.; Nishimori, M.

2017-12-01

Meteorological extremes of temperature and precipitation are a critical issue in the global climate change, and some studies investigating how the extreme changes in accordance with the climate change are continuously reported. However, it is rarely understandable that the extremes affect crop yield worldwide as heatwave, coolwave, drought, and flood, albeit some local or national reports are available. Therefore, we globally investigated the extremes effects on the variability of historical yield of maize, rice, soy, and wheat with a standardized index and a historical yield anomaly. For the regression analysis, the standardized index is annually aggregated in the consideration of a crop calendar, and the historical yield is detrended with 5-year moving average. Throughout this investigation, we found that the relationship between the aggregated standardized index and the historical yield anomaly shows not merely positive correlation but also negative correlation in all crops in the globe. Namely, the extremes cause decrease of crop yield as a matter of course, but increase in some regions contrastingly. These results help us to quantify the extremes effect on historical crop yield anomaly.

1976 Oregon timber harvest.

Treesearch

J.D. Jr. Lloyd

1978-01-01

The 1976 Oregon timber harvest of 8.15 billion board feet ended a 3-year decline. The cut was 783 million board feet (10.6 percent) above the 1975 harvest. The western Oregon harvest rose 812 million board feet (15 percent) while eastern Oregon declined 29 million board feet (15 percent). The proportion of total harvest which comes from eastern Oregon has gradually...

Climate change impacts on crop yield: evidence from China.

PubMed

Wei, Taoyuan; Cherry, Todd L; Glomrød, Solveig; Zhang, Tianyi

2014-11-15

When estimating climate change impact on crop yield, a typical assumption is constant elasticity of yield with respect to a climate variable even though the elasticity may be inconstant. After estimating both constant and inconstant elasticities with respect to temperature and precipitation based on provincial panel data in China 1980-2008, our results show that during that period, the temperature change contributes positively to total yield growth by 1.3% and 0.4% for wheat and rice, respectively, but negatively by 12% for maize. The impacts of precipitation change are marginal. We also compare our estimates with other studies and highlight the implications of the inconstant elasticities for crop yield, harvest and food security. We conclude that climate change impact on crop yield would not be an issue in China if positive impacts of other socio-economic factors continue in the future. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of wheat stem sawfly damage on yield and quality of selected Canadian spring wheat.

PubMed

Beres, B L; Cárcamo, H A; Byers, J R

2007-02-01

The wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), has reached outbreak status at most locations in the southern Canadian prairies. Solid-stemmed wheat, Triticum aestivum L., cultivars, which are less susceptible to damage, remain the primary management option. This article quantifies the effect of wheat stem sawfly damage on grain yield and quality at harvest and determines how cultivar selection affects harvest losses. Solid-stemmed cultivars were compared with hollow-stemmed cultivars and with blends of a 1:1 ratio of each. The hollow-stemmed cultivars with the exception of'McKenzie', which had intermediate levels of stem cutting, were all significantly more susceptible to stem cutting than solid-stemmed cultivars. Cultivar blends had lower damage but were still significantly higher than the solid-stemmed cultivars. The solid-stemmed 'AC Eatonia' and 'AC Abbey' had the lowest levels of stem cutting and ranked second and third overall for yield in 2001 and 2002. McKenzie ranked first, which reflects its yield potential in combination with its partial resistance to stem cutting. Lower cutting in AC Eatonia, AC Abbey, McKenzie, and the blend of AC Abbey/ McKenzie was significantly correlated with lower grain losses. Grain lost at harvest has major economic implications if sawfly pressure is moderate to high and susceptible cultivars predominate.

Black Truffle Harvesting in Spanish Forests: Trends, Current Policies and Practices, and Implications on its Sustainability

NASA Astrophysics Data System (ADS)

Garcia-Barreda, Sergi; Forcadell, Ricardo; Sánchez, Sergio; Martín-Santafé, María; Marco, Pedro; Camarero, J. Julio; Reyna, Santiago

2018-04-01

The European black truffle is a mycorrhizal fungus native to Spanish Mediterranean forests. In most Spanish regions it was originally commercially harvested in the second half of the 20th century. Experts agree that wild truffle yields suffered a sharp decline during the 1970s and 1980s. However, official statistics for Spanish harvest are scarce and seemingly conflicting, and little attention has been paid to the regime for the exploitation of truffle-producing forests and its implications on the sustainability of this resource. Trends in harvest from 1969 to 2013 and current harvesting practices were analyzed as a case study, taking into account that Spain is a major truffle producer worldwide, but at the same time truffles have only recently been exploited. The available statistical sources, which include an increasing proportion of cultivated truffles since the mid-1990s, were explored, with estimates from Truffle Harvesters Federation showing higher consistency. Statistical sources were then compared with proxies for wild harvest (rents from truffle leases in public forests) to corroborate time trends in wild harvesting. Results suggest that black truffle production is recovering in recent years thanks to plantations, whereas wild harvest is still declining. The implications of Spanish legal and institutional framework on sustainability of wild truffle use are reviewed. In the current scenario, the decline of wild harvest is likely to continue and eventually make commercial harvesting economically unattractive, thus aggravating sustainability issues. Strengthening of property rights, rationalization of harvesting pressure, forest planning and involvement of public stakeholders are proposed as corrective measures.

Variability in soybean yield in Brazil stemming from the interaction of heterogeneous management and climate variability

NASA Astrophysics Data System (ADS)

Cohn, A.; Bragança, A.; Jeffries, G. R.

2017-12-01

An increasing share of global agricultural production can be found in the humid tropics. Therefore, an improved understanding of the mechanisms governing variability in the output of tropical agricultural systems is of increasing importance for food security including through climate change adaptation. Yet, the long window over which many tropical crops can be sown, the diversity of crop varieties and management practices combine to challenge inference into climate risk to cropping output in analyses of tropical crop-climate sensitivity employing administrative data. In this paper, we leverage a newly developed spatially explicit dataset of soybean yields in Brazil to combat this problem. The dataset was built by training a model of remotely-sensed vegetation index data and land cover classification data using a rich in situ dataset of soybean yield and management variables collected over the period 2006 to 2016. The dataset contains soybean yields by plant date, cropping frequency, and maturity group for each 5km grid cell in Brazil. We model variation in these yields using an approach enabling the estimation of the influence of management factors on the sensitivity of soybean yields to variability in: cumulative solar radiation, extreme degree days, growing degree days, flooding rain in the harvest period, and dry spells in the rainy season. We find strong variation in climate sensitivity by management class. Planting date and maturity group each explained a great deal more variation in yield sensitivity than did cropping frequency. Brazil collects comparatively fine spatial resolution yield data. But, our attempt to replicate our results using administrative soy yield data revealed substantially lesser crop-climate sensitivity; suggesting that previous analyses employing administrative data may have underestimated climate risk to tropical soy production.

Definition of architectural ideotypes for good yield capacity in Coffea canephora.

PubMed

Cilas, Christian; Bar-Hen, Avner; Montagnon, Christophe; Godin, Christophe

2006-03-01

Yield capacity is a target trait for selection of agronomically desirable lines; it is preferred to simple yields recorded over different harvests. Yield capacity is derived using certain architectural parameters used to measure the components of yield capacity. Observation protocols for describing architecture and yield capacity were applied to six clones of coffee trees (Coffea canephora) in a comparative trial. The observations were used to establish architectural databases, which were explored using AMAPmod, a software dedicated to the analyses of plant architecture data. The traits extracted from the database were used to identify architectural parameters for predicting the yield of the plant material studied. Architectural traits are highly heritable and some display strong genetic correlations with cumulated yield. In particular, the proportion of fruiting nodes at plagiotropic level 15 counting from the top of the tree proved to be a good predictor of yield over two fruiting cycles.

The impact of donor characteristics on the immune cell composition of mixture allografts of granulocyte-colony-stimulating factor-mobilized marrow harvests and peripheral blood harvests.

PubMed

Wang, Yu-Tong; Zhao, Xiang-Yu; Zhao, Xiao-Su; Xu, Lan-Ping; Zhang, Xiao-Hui; Wang, Yu; Liu, Kai-Yan; Chang, Ying-Jun; Huang, Xiao-Jun

2015-12-01

The association of donor characteristics with immune cell composition in allografts remains poorly understood. In this retrospective study, the effects of donor characteristics on immune cell composition in allografts were investigated. The correlations of donor characteristics with the immune cell composition in mixture allografts of granulocyte-colony-stimulating factor-mobilized marrow harvests and peripheral blood harvests of 390 healthy donors (male, 240; female, 150; median age, 40 years old) were analyzed. The median doses of CD3+ T cells, CD4+ T cells, CD8+ T cells, CD3+CD4-CD8- T cells, and monocytes in mixture allografts were 160.57 × 10(6), 89.29 × 10(6), 56.16 × 10(6), 10.87 × 10(6), and 137.94 × 10(6)/kg, respectively. Multivariate analysis showed that younger donor age was associated with a higher dose of CD3+ T cells (p = 0.006), CD3+CD8+ T cells (p < 0.001), CD3+CD4-CD8- T cells (p = 0.004), and monocytes (p = 0.014), as well as a higher ratio of CD3+CD4-CD8- T cells/CD3+ T cells (p < 0.001) in the mixture allografts. A negative association of donor weight with CD3+ T cells (p < 0.001), CD4+ T cells (p = 0.002), CD8+ T cells (p < 0.001), and CD3+CD4-CD8- T cells (p = 0.044) was observed. The count of peripheral blood lymphocyte pre-peripheral blood apheresis was correlated with the yield of CD3+ T cells (p < 0.001) and CD4+ T cells (p = 0.001). The peripheral blood monocyte count before marrow harvest predicted the monocyte dose (p = 0.002). The results suggested that older and overweight donors should not be chosen. The monocyte and lymphocyte counts before harvest could predict the yield of immune cells in allografts. © 2015 AABB.

1974 Oregon timber harvest.

Treesearch

J.D. Jr. Lloyd

1976-01-01

The 1974 Oregon timber harvest of 8.36 billion board feet was 9.2 percent, or 0.84 billion board feet, below the 1973 harvest. (The data for 1973 were adjusted to reflect the change in reporting of harvest on Bureau of Land Management lands; see footnote 3 of table.) While the harvest in western Oregon decreased 14.7 percent, eastern Oregon cut increased 11.5 percent...

Analog self-powered harvester achieving switching pause control to increase harvested energy

NASA Astrophysics Data System (ADS)

Makihara, Kanjuro; Asahina, Kei

2017-05-01

In this paper, we propose a self-powered analog controller circuit to increase the efficiency of electrical energy harvesting from vibrational energy using piezoelectric materials. Although the existing synchronized switch harvesting on inductor (SSHI) method is designed to produce efficient harvesting, its switching operation generates a vibration-suppression effect that reduces the harvested levels of electrical energy. To solve this problem, the authors proposed—in a previous paper—a switching method that takes this vibration-suppression effect into account. This method temporarily pauses the switching operation, allowing the recovery of the mechanical displacement and, therefore, of the piezoelectric voltage. In this paper, we propose a self-powered analog circuit to implement this switching control method. Self-powered vibration harvesting is achieved in this study by attaching a newly designed circuit to an existing analog controller for SSHI. This circuit aims to effectively implement the aforementioned new switching control strategy, where switching is paused in some vibration peaks, in order to allow motion recovery and a consequent increase in the harvested energy. Harvesting experiments performed using the proposed circuit reveal that the proposed method can increase the energy stored in the storage capacitor by a factor of 8.5 relative to the conventional SSHI circuit. This proposed technique is useful to increase the harvested energy especially for piezoelectric systems having large coupling factor.

Statistical rice yield modeling using blended MODIS-Landsat based crop phenology metrics in Taiwan

NASA Astrophysics Data System (ADS)

Chen, C. R.; Chen, C. F.; Nguyen, S. T.; Lau, K. V.

2015-12-01

Taiwan is a populated island with a majority of residents settled in the western plains where soils are suitable for rice cultivation. Rice is not only the most important commodity, but also plays a critical role for agricultural and food marketing. Information of rice production is thus important for policymakers to devise timely plans for ensuring sustainably socioeconomic development. Because rice fields in Taiwan are generally small and yet crop monitoring requires information of crop phenology associating with the spatiotemporal resolution of satellite data, this study used Landsat-MODIS fusion data for rice yield modeling in Taiwan. We processed the data for the first crop (Feb-Mar to Jun-Jul) and the second (Aug-Sep to Nov-Dec) in 2014 through five main steps: (1) data pre-processing to account for geometric and radiometric errors of Landsat data, (2) Landsat-MODIS data fusion using using the spatial-temporal adaptive reflectance fusion model, (3) construction of the smooth time-series enhanced vegetation index 2 (EVI2), (4) rice yield modeling using EVI2-based crop phenology metrics, and (5) error verification. The fusion results by a comparison bewteen EVI2 derived from the fusion image and that from the reference Landsat image indicated close agreement between the two datasets (R2 > 0.8). We analysed smooth EVI2 curves to extract phenology metrics or phenological variables for establishment of rice yield models. The results indicated that the established yield models significantly explained more than 70% variability in the data (p-value < 0.001). The comparison results between the estimated yields and the government's yield statistics for the first and second crops indicated a close significant relationship between the two datasets (R2 > 0.8), in both cases. The root mean square error (RMSE) and mean absolute error (MAE) used to measure the model accuracy revealed the consistency between the estimated yields and the government's yield statistics. This

Peanut peg strength and associated pod yield and loss by cultivar

USDA-ARS?s Scientific Manuscript database

Peanut (Arachis hypogaea L.) peg strength and associated pod yield and digging loss were documented for nine cultivars and two breeding genotypes across three harvest dates at two Southwest Georgia locations during 2010 and 2011. Cultivars selected were Georgia Green, Georgia Greener, Georgia-02C, G...

Growth, pod, and seed yield, and gas exchange of hydroponically grown peanut in response to CO2 enrichment

NASA Technical Reports Server (NTRS)

Stanciel, K.; Mortley, D. G.; Hileman, D. R.; Loretan, P. A.; Bonsi, C. K.; Hill, W. A.

2000-01-01

The effects of elevated CO2 on growth, pod, and seed yield, and gas exchange of 'Georgia Red' peanut (Arachis hypogaea L.) were evaluated under controlled environmental conditions. Plants were exposed to concentrations of 400 (ambient), 800, and 1200 micromoles mol-1 CO2 in reach-in growth chambers. Foliage fresh and dry weights increased with increased CO2 up to 800 micromoles mol-1, but declined at 1200 micromoles mol-1. The number and the fresh and dry weights of pods also increased with increasing CO2 concentration. However, the yield of immature pods was not significantly influenced by increased CO2. Total seed yield increased 33% from ambient to 800 micromoles mol-1 CO2, and 4% from 800 to 1200 micromoles mol-1 CO2. Harvest index increased with increasing CO2. Branch length increased while specific leaf area decreased linearly as CO2 increased from ambient to 1200 micromoles mol-1. Net photosynthetic rate was highest among plants grown at 800 micromoles mol-1. Stomatal conductance decreased with increased CO2. Carboxylation efficiency was similar among plants grown at 400 and 800 micromoles mol-1 and decreased at 1200 micromoles mol-1 CO2. These results suggest that CO2 enrichment from 400 to 800 micromoles mol-1 had positive effects on peanut growth and yield, but above 800 micromoles mol-1 enrichment seed yield increased only marginally.

Influence of Harvest Aid Herbicides on Seed Germination, Seedling Vigor and Milling Quality Traits of Red Lentil (Lens culinaris L.).

PubMed

Subedi, Maya; Willenborg, Christian J; Vandenberg, Albert

2017-01-01

Most red lentil produced worldwide is consumed in dehulled form, and post-harvest milling and splitting qualities are major concerns in the secondary processing industry. Lentil producers in northern temperate regions usually apply pre-harvest desiccants as harvest aids to accelerate the lentil crop drying process and facilitate harvesting operations. This paper reports on field studies conducted at Scott and Saskatoon, Saskatchewan, Canada in the 2012 and 2013 cropping seasons to evaluate whether herbicides applied as harvest aids alone or tank mixed with glyphosate affect seed germination, seedling vigor, milling, and splitting qualities. The site-year by desiccant treatment interaction for seed germination, vigor, and milling recovery yields was significant. Glyphosate applied alone or as tank mix with other herbicides (except diquat) reduced seed germination and seedling vigor at Saskatoon and Scott in 2012 only. Pyraflufen-ethyl (20 g ai ha -1 ) applied with glyphosate as well as saflufenacil (36 g ai ha -1 ) decreased dehulling efficiency, while saflufenacil and/or glufosinate with glyphosate reduced milling recovery and football recovery, although these effects were inconsistent. Application of diquat alone or in combination with glyphosate exhibited more consistent dehulling efficiency gains and increases in milling recovery yield. Significant but negative associations were observed between glyphosate residue in seeds and seed germination ( r = -0.84, p < 0.001), seed vigor ( r = -0.62, p < 0.001), dehulling efficiency ( r = -0.55, p < 0.001), and milling recovery ( r = -0.62, p < 0.001). These results indicate application of diquat alone or in combination with glyphosate may be a preferred option for lentil growers to improve milling recovery yield.

Influence of Harvest Aid Herbicides on Seed Germination, Seedling Vigor and Milling Quality Traits of Red Lentil (Lens culinaris L.)

PubMed Central

Subedi, Maya; Willenborg, Christian J.; Vandenberg, Albert

2017-01-01

Most red lentil produced worldwide is consumed in dehulled form, and post-harvest milling and splitting qualities are major concerns in the secondary processing industry. Lentil producers in northern temperate regions usually apply pre-harvest desiccants as harvest aids to accelerate the lentil crop drying process and facilitate harvesting operations. This paper reports on field studies conducted at Scott and Saskatoon, Saskatchewan, Canada in the 2012 and 2013 cropping seasons to evaluate whether herbicides applied as harvest aids alone or tank mixed with glyphosate affect seed germination, seedling vigor, milling, and splitting qualities. The site-year by desiccant treatment interaction for seed germination, vigor, and milling recovery yields was significant. Glyphosate applied alone or as tank mix with other herbicides (except diquat) reduced seed germination and seedling vigor at Saskatoon and Scott in 2012 only. Pyraflufen-ethyl (20 g ai ha−1) applied with glyphosate as well as saflufenacil (36 g ai ha−1) decreased dehulling efficiency, while saflufenacil and/or glufosinate with glyphosate reduced milling recovery and football recovery, although these effects were inconsistent. Application of diquat alone or in combination with glyphosate exhibited more consistent dehulling efficiency gains and increases in milling recovery yield. Significant but negative associations were observed between glyphosate residue in seeds and seed germination (r = −0.84, p < 0.001), seed vigor (r = −0.62, p < 0.001), dehulling efficiency (r = −0.55, p < 0.001), and milling recovery (r = −0.62, p < 0.001). These results indicate application of diquat alone or in combination with glyphosate may be a preferred option for lentil growers to improve milling recovery yield. PMID:28352275

The effect of harvest time, dry matter content and mechanical pretreatments on anaerobic digestion and enzymatic hydrolysis of miscanthus.

PubMed

Frydendal-Nielsen, Susanne; Hjorth, Maibritt; Baby, Sanmohan; Felby, Claus; Jørgensen, Uffe; Gislum, René

2016-10-01

Miscanthus x giganteus was harvested as both green and mature biomass and the dry matter content of the driest harvest was artificially decreased by adding water in two subsamples, giving a total of five dry matter contents. All five biomass types were mechanically pretreated by roller-milling, extrusion or grinding and accumulated methane production and enzymatically-accessible sugars were measured. Accumulated methane production was studied using sigmoid curves that allowed comparison among the treatments of the rate of the methane production and ultimate methane yield. The green biomass gave the highest methane yield and highest levels of enzymatically-accessible cellulose. The driest biomass gave the best effect from extrusion but with the highest energy consumption, whereas roller-milling was most efficient on wet biomass. The addition of water to the last harvest improved the effect of roller-milling and equalled extrusion of the samples in efficiency. Copyright © 2016 Elsevier Ltd. All rights reserved.

Using Grizzly Bears to Assess Harvest-Ecosystem Tradeoffs in Salmon Fisheries

PubMed Central

MacDuffee, Misty; Mangel, Marc; Paquet, Paul; Wilmers, Christopher C.

2012-01-01

Implementation of ecosystem-based fisheries management (EBFM) requires a clear conceptual and quantitative framework for assessing how different harvest options can modify benefits to ecosystem and human beneficiaries. We address this social-ecological need for Pacific salmon fisheries, which are economically valuable but intercept much of the annual pulse of nutrient subsidies that salmon provide to terrestrial and aquatic food webs. We used grizzly bears, vectors of salmon nutrients and animals with densities strongly coupled to salmon abundance, as surrogates for “salmon ecosystem” function. Combining salmon biomass and stock-recruitment data with stable isotope analysis, we assess potential tradeoffs between fishery yields and bear population densities for six sockeye salmon stocks in Bristol Bay, Alaska, and British Columbia (BC), Canada. For the coastal stocks, we find that both bear densities and fishery yields would increase substantially if ecosystem allocations of salmon increase from currently applied lower to upper goals and beyond. This aligning of benefits comes at a potential cost, however, with the possibility of forgoing harvests in low productivity years. In contrast, we detect acute tradeoffs between bear densities and fishery yields in interior stocks within the Fraser River, BC, where biomass from other salmon species is low. There, increasing salmon allocations to ecosystems would benefit threatened bear populations at the cost of reduced long-term yields. To resolve this conflict, we propose an EBFM goal that values fisheries and bears (and by extension, the ecosystem) equally. At such targets, ecosystem benefits are unexpectedly large compared with losses in fishery yields. To explore other management options, we generate tradeoff curves that provide stock-specific accounting of the expected loss to fishers and gain to bears as more salmon escape the fishery. Our approach, modified to suit multiple scenarios, provides a generalizable

Using grizzly bears to assess harvest-ecosystem tradeoffs in salmon fisheries.

PubMed

Levi, Taal; Darimont, Chris T; Macduffee, Misty; Mangel, Marc; Paquet, Paul; Wilmers, Christopher C

2012-01-01

Implementation of ecosystem-based fisheries management (EBFM) requires a clear conceptual and quantitative framework for assessing how different harvest options can modify benefits to ecosystem and human beneficiaries. We address this social-ecological need for Pacific salmon fisheries, which are economically valuable but intercept much of the annual pulse of nutrient subsidies that salmon provide to terrestrial and aquatic food webs. We used grizzly bears, vectors of salmon nutrients and animals with densities strongly coupled to salmon abundance, as surrogates for "salmon ecosystem" function. Combining salmon biomass and stock-recruitment data with stable isotope analysis, we assess potential tradeoffs between fishery yields and bear population densities for six sockeye salmon stocks in Bristol Bay, Alaska, and British Columbia (BC), Canada. For the coastal stocks, we find that both bear densities and fishery yields would increase substantially if ecosystem allocations of salmon increase from currently applied lower to upper goals and beyond. This aligning of benefits comes at a potential cost, however, with the possibility of forgoing harvests in low productivity years. In contrast, we detect acute tradeoffs between bear densities and fishery yields in interior stocks within the Fraser River, BC, where biomass from other salmon species is low. There, increasing salmon allocations to ecosystems would benefit threatened bear populations at the cost of reduced long-term yields. To resolve this conflict, we propose an EBFM goal that values fisheries and bears (and by extension, the ecosystem) equally. At such targets, ecosystem benefits are unexpectedly large compared with losses in fishery yields. To explore other management options, we generate tradeoff curves that provide stock-specific accounting of the expected loss to fishers and gain to bears as more salmon escape the fishery. Our approach, modified to suit multiple scenarios, provides a generalizable method

Toward a semi-mechanical harvesting platform system for harvesting blueberries with fresh-market quality

USDA-ARS?s Scientific Manuscript database

Major concerns related to harvesting blueberries for fresh market with over-the-row (OTR) harvesters are that the quality of the fruit harvested with OTR machines is generally low and ground loss is excessive. Machine-harvested blueberries have more internal bruise and usually soften rapidly in col...

Effect of elevated [CO2 ] on yield, intra-plant nutrient dynamics, and grain quality of rice cultivars in Eastern India.

PubMed

Jena, Usha Rani; Swain, Dillip Kumar; Hazra, K K; Maity, Mrinal K

2018-05-16

Climate models predict an increase in global temperature in response to a doubling of atmospheric [CO 2 ] that may impact future rice production and quality. In this study, the effect of elevated [CO 2 ] on yield, nutrient acquisition and utilization, and grain quality of rice genotypes was investigated in subtropical climate of eastern India (Kharagpur). Three environments (open field, ambient, and elevated [CO 2 ]) were tested using four rice cultivars of eastern India. Under elevated [CO 2 ] (25% higher), yield of high yielding cultivars (HYCs) viz. IR 36, Swarna, and Swarna sub1 was significantly reduced (11-13%), whereas the yield increased (6-9%) for Badshabhog, a low-yielding aromatic cultivar. Elevated [CO 2 ] significantly enhanced K uptake (14-21%), but did not influence the uptake of total N and P. The nutrient harvest index and use efficiency values in HYCs were reduced under elevated [CO 2 ] indicating that nutrients translocation from source to sink (grain) was significantly reduced. An increase in alkali spreading value (10%) and reduction in grain protein (2-3%) and iron (5-6%) was also observed upon [CO 2 ] elevation. The study highlights the importance of nutrient management (increasing N rate for HYCs) and selective breeding of tolerant cultivar in minimizing the adverse effect of elevated [CO 2 ] on rice yield and quality. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Economic weights for genetic improvement of lactation persistency and milk yield.

PubMed

Togashi, K; Lin, C Y

2009-06-01

This study aimed to establish a criterion for measuring the relative weight of lactation persistency (the ratio of yield at 280 d in milk to peak yield) in restricted selection index for the improvement of net merit comprising 3-parity total yield and total lactation persistency. The restricted selection index was compared with selection based on first-lactation total milk yield (I(1)), the first-two-lactation total yield (I(2)), and first-three-lactation total yield (I(3)). Results show that genetic response in net merit due to selection on restricted selection index could be greater than, equal to, or less than that due to the unrestricted index depending upon the relative weight of lactation persistency and the restriction level imposed. When the relative weight of total lactation persistency is equal to the criterion, the restricted selection index is equal to the selection method compared (I(1), I(2), or I(3)). The restricted selection index yielded a greater response when the relative weight of total lactation persistency was above the criterion, but a lower response when it was below the criterion. The criterion varied depending upon the restriction level (c) imposed and the selection criteria compared. A curvilinear relationship (concave curve) exists between the criterion and the restricted level. The criterion increases as the restriction level deviates in either direction from 1.5. Without prior information of the economic weight of lactation persistency, the imposition of the restriction level of 1.5 on lactation persistency would maximize change in net merit. The procedure presented allows for simultaneous modification of multi-parity lactation curves.

Designing and Evaluating Bamboo Harvesting Methods for Local Needs: Integrating Local Ecological Knowledge and Science.

PubMed

Darabant, András; Rai, Prem Bahadur; Staudhammer, Christina Lynn; Dorji, Tshewang

2016-08-01

Dendrocalamus hamiltonii, a large, clump-forming bamboo, has great potential to contribute towards poverty alleviation efforts across its distributional range. Harvesting methods that maximize yield while they fulfill local objectives and ensure sustainability are a research priority. Documenting local ecological knowledge on the species and identifying local users' goals for its production, we defined three harvesting treatments (selective cut, horseshoe cut, clear cut) and experimentally compared them with a no-intervention control treatment in an action research framework. We implemented harvesting over three seasons and monitored annually and two years post-treatment. Even though the total number of culms positively influenced the number of shoots regenerated, a much stronger relationship was detected between the number of culms harvested and the number of shoots regenerated, indicating compensatory growth mechanisms to guide shoot regeneration. Shoot recruitment declined over time in all treatments as well as the control; however, there was no difference among harvest treatments. Culm recruitment declined with an increase in harvesting intensity. When univariately assessing the number of harvested culms and shoots, there were no differences among treatments. However, multivariate analyses simultaneously considering both variables showed that harvested output of shoots and culms was higher with clear cut and horseshoe cut as compared to selective cut. Given the ease of implementation and issues of work safety, users preferred the horseshoe cut, but the lack of sustainability of shoot production calls for investigating longer cutting cycles.

Stump Harvesting

Treesearch

Dana Mitchell

2009-01-01

Increased use of forest fuel requires larger and larger procurement areas. Inclusion of stump material within the shorter distances could make this unusual source of biomass more economical to harvest. Land clearing activities are also helping to raise interest in stump harvesting. Processing stump material for biomass is an alternative...

Environmental and socioeconomic benefits and limitations of water harvesting techniques in semiarid regions

NASA Astrophysics Data System (ADS)

Díaz-Pereira, Elvira; Asunción Romero-Díaz, María; de Vente, Joris

2016-04-01

water harvesting are increased crop yield and farm income. Their implementation also leads to an improved food security and knowledge of soil erosion and conservation and to strengthening of social networks. Their main environmental benefits include an increased soil moisture content and water availability, reduced soil loss and reduced downstream flooding and siltation. These impacts have positive implications for a range of regulating (flood control), provisioning (food production), supporting (nutrient cycling) and cultural (aesthetic value) ecosystem services. Despite their many perceived potential benefits, the main constraints for local implementation of water harvesting techniques are due to labour constraints, implementation costs and the loss of productive land. This highlights the need for political solutions including incentives for implementation for most effective water harvesting techniques adapted to local environmental and socioeconomic conditions.

Shorter Harvest Cycles Counteract Increasing Annual Productivity in Industrial Plantation Forests: Trends from Three Decades of Remote Sensing in Southeastern Brazil

NASA Astrophysics Data System (ADS)

McMahon, D.; Jackson, R. B.

2017-12-01

Plantation forestry can produce woody biomass many times faster than native vegetation, particularly in the tropical regions where plantations have expanded rapidly in the past three decades. However, activists and practitioners have raised concerns over the sustainability of intensive plantations, suggesting that changes to soil properties may inhibit vegetation growth after multiple harvest cycles. We use a 32-year time series of remotely sensed vegetation indices derived from Landsat data, coupled with recent geospatial and wood volume data from plantation companies, to identify trends in management and vegetation productivity in thousands of individual eucalyptus plantation stands. We find that peak vegetation index values at canopy closure, which are correlated with annual wood volume increment, increase over successive harvest cycles, while the length of each cycle decreases. These opposing trends suggest that the number of harvests required to produce a given wood volume peaks around the second harvest cycle and then declines, likely due to refinement of management practices. Across the region, vegetation index data do not support the hypothesized decrease in productivity over multiple harvest cycles. Additional field data and ongoing soil analyses will complement the remote sensing approach to quantifying plantations' long-term effects on the land they occupy.

The economics of a mechanized multiproduct harvesting system for stand conversion of northern hardwoods.

Treesearch

John A. Sturos; Edwin S. Miyata; Helmuth M. Steinhilb; Robert M. Barron

1983-01-01

Describes chip and saw log yields, production, costs, and potential profits of clearcutting, down to a 2-inch diameter, a northern hardwood poletimber stand by a conventional whole-tree harvesting system and three sawtimber stands by several combinations of whole-tree chipping and saw log recovery.

Maximum sustainable yield and species extinction in a prey-predator system: some new results.

PubMed

Ghosh, Bapan; Kar, T K

2013-06-01

Though the maximum sustainable yield (MSY) approach has been legally adopted for the management of world fisheries, it does not provide any guarantee against from species extinction in multispecies communities. In the present article, we describe the appropriateness of the MSY policy in a Holling-Tanner prey-predator system with different types of functional responses. It is observed that for both type I and type II functional responses, harvesting of either prey or predator species at the MSY level is a sustainable fishing policy. In the case of combined harvesting, both the species coexist at the maximum sustainable total yield (MSTY) level if the biotic potential of the prey species is greater than a threshold value. Further, increase of the biotic potential beyond the threshold value affects the persistence of the system.

Biosecurity and Yield Improvement Technologies Are Strategic Complements in the Fight against Food Insecurity

PubMed Central

Cook, David C.; Fraser, Rob W.; Paini, Dean R.; Warden, Andrew C.; Lonsdale, W. Mark; De Barro, Paul J.

2011-01-01

The delivery of food security via continued crop yield improvement alone is not an effective food security strategy, and must be supported by pre- and post-border biosecurity policies to guard against perverse outcomes. In the wake of the green revolution, yield gains have been in steady decline, while post-harvest crop losses have increased as a result of insufficiently resourced and uncoordinated efforts to control spoilage throughout global transport and storage networks. This paper focuses on the role that biosecurity is set to play in future food security by preventing both pre- and post-harvest losses, thereby protecting crop yield. We model biosecurity as a food security technology that may complement conventional yield improvement policies if the gains in global farm profits are sufficient to offset the costs of implementation and maintenance. Using phytosanitary measures that slow global spread of the Ug99 strain of wheat stem rust as an example of pre-border biosecurity risk mitigation and combining it with post-border surveillance and invasive alien species control efforts, we estimate global farm profitability may be improved by over US$4.5 billion per annum. PMID:22022517

Stand, Harvest, and Equipment Interactions in Simulated Harvesting Prescriptions

Treesearch

Jingxin Wang; W. Dale Greene; Bryce J. Stokes

1998-01-01

We evaluated potential interactions of stand type, harvesting method, and equipment in an experiment using interactive simulation. We examined three felling methods (chain saw, feller-buncher, harvester) and two extraction methods (grapple skidder and forwarder) performing clearcuts, sheltenvood cuts, and single-tree selection cuts in both an uneven-aged natural stand...

Impacts of industrial waste resources on maize (Zea mays L.) growth, yield, nutrients uptake and soil properties.

PubMed

Singh, Satnam; Young, Li-Sen; Shen, Fo-Ting; Young, Chiu-Chung

2014-10-01

Discharging untreated highly acidic (pH<4.0), organic and nutrients rich monosodium glutamate wastewater (MW), and highly alkaline (pH>10.0) paper-mill wastewater (PW) causes environmental pollution. When acidity of MW neutralized (pH 6.5±0.1) with PW and lime (treatments represented as MW+PW and MW+Lime), then MW may be utilized as a potential source of nutrients and organic carbon for sustainable food production. Objectives of this study were to compare the effects of PW and lime neutralized MW and chemical fertilizers on maize (Zea mays L. cv. Snow Jean) plant growth, yield, nutrients uptake, soil organic matter and humic substances. The field experiment was carried out on maize using MW at 6000 L ha(-1). Impacts of the MW application on maize crop and soil properties were evaluated at different stages. At harvest, plant height, and plant N and K uptake were higher in MW treatment. Leaf area index at 60 days after sowing, plant dry matter accumulation at harvest, and kernels ear(-1) and 100-kernel weight were higher in MW+Lime treatment. Kernel N, P, K, Mn, Fe and Zn, and plant Zn uptake were highest in MW+Lime. Plant Fe uptake, and soil organic matter and humic substances were highest in MW+PW. The MW+PW and MW+Lime treatments exhibited comparable results with chemically fertilized treatment. The MW acidity neutralized with lime showed positive impacts on growth, yield and nutrients uptake; nevertheless, when MW pH neutralized with PW has an additional benefit on increase in soil organic matter and humic substances. Copyright © 2014. Published by Elsevier Ltd.

Yield and water quality for different residue managements of sugarcane in Louisiana

USDA-ARS?s Scientific Manuscript database

The focus of the study was to provide information on implementation of a modified post-harvest crop residue sweeper on sugarcane yield and water quality. Field experiments were established at three different locations in south Louisiana: Paincourtville, Duson and Baton Rouge. In each location, lar...

Effects of regulated deficit irrigation during the pre-harvest period on gas exchange, leaf development and crop yield of mature almond trees.

PubMed

Romero, Pascual; Navarro, Josefa Maria; García, Francisco; Botía Ordaz, Pablo

2004-03-01

We investigated the effects of regulated deficit irrigation (RDI) during the pre-harvest period (kernel-filling stage) on water relations, leaf development and crop yield in mature almond (Prunus dulcis (Mill.) D.A. Webb cv. Cartagenera) trees during a 2-year field experiment. Trees were either irrigated at full-crop evapotranspiration (ETc=100%) (well-irrigated control treatment) or subjected to an RDI treatment that consisted of full irrigation for the full season, except from early June to early August (kernel-filling stage), when 20% ETc was applied. The severity of water stress was characterized by measurements of soil water content, predawn leaf water potential (Psipd) and relative water content (RWC). Stomatal conductance (gs), net CO2 assimilation rate (A), transpiration rate (E), leaf abscission, leaf expansion rate and crop yield were also measured. In both years, Psipd and RWC of well-irrigated trees were maintained above -1.0 MPa and 92%, respectively, whereas the corresponding values for trees in the RDI treatment were -2.37 MPa and 82%. Long-term water stress led to a progressive decline in gs, A and E, with significant reductions after 21 days in the RDI treatment. At the time of maximum stress (48 days after commencement of RDI), A, gs and E were 64, 67 and 56% lower than control values, respectively. High correlations between A, E and gs were observed. Plant water status recovered within 15 days after the resumption of irrigation and was associated with recovery of soil water content. A relatively rapid and complete recovery of A and gs was also observed, although the recovery was slower than for Psipd and RWC. Severe water stress during the kernel-filling stage resulted in premature defoliation (caused by increased leaf abscission) and a reduction in leaf growth rate, which decreased tree leaf area. Although kernel yield was correlated with leaf water potential, RDI caused a nonsignificant 7% reduction in kernel yield and had no effect on kernel

Normalized Difference Vegetation Index as a Tool for Wheat Yield Estimation: A Case Study from Faisalabad, Pakistan

PubMed Central

Sultana, Syeda Refat; Ali, Amjed; Ahmad, Ashfaq; Mubeen, Muhammad; Zia-Ul-Haq, M.; Ahmad, Shakeel; Ercisli, Sezai; Jaafar, Hawa Z. E.

2014-01-01

For estimation of grain yield in wheat, Normalized Difference Vegetation Index (NDVI) is considered as a potential screening tool. Field experiments were conducted to scrutinize the response of NDVI to yield behavior of different wheat cultivars and nitrogen fertilization at agronomic research area, University of Agriculture Faisalabad (UAF) during the two years 2008-09 and 2009-10. For recording the value of NDVI, Green seeker (Handheld-505) was used. Split plot design was used as experimental model in, keeping four nitrogen rates (N1 = 0 kg ha−1, N2 = 55 kg ha−1, N3 = 110 kg ha−1, and N4 = 220 kg ha−1) in main plots and ten wheat cultivars (Bakkhar-2001, Chakwal-50, Chakwal-97, Faisalabad-2008, GA-2002, Inqlab-91, Lasani-2008, Miraj-2008, Sahar-2006, and Shafaq-2006) in subplots with four replications. Impact of nitrogen and difference between cultivars were forecasted through NDVI. The results suggested that nitrogen treatment N4 (220 kg ha−1) and cultivar Faisalabad-2008 gave maximum NDVI value (0.85) at grain filling stage among all treatments. The correlation among NDVI at booting, grain filling, and maturity stages with grain yield was positive (R 2 = 0.90; R 2 = 0.90; R 2 = 0.95), respectively. So, booting, grain filling, and maturity can be good depictive stages during mid and later growth stages of wheat crop under agroclimatic conditions of Faisalabad and under similar other wheat growing environments in the country. PMID:25045744

Optimal harvesting policy of a stochastic two-species competitive model with Lévy noise in a polluted environment

NASA Astrophysics Data System (ADS)

Zhao, Yu; Yuan, Sanling

2017-07-01

As well known that the sudden environmental shocks and toxicant can affect the population dynamics of fish species, a mechanistic understanding of how sudden environmental change and toxicant influence the optimal harvesting policy requires development. This paper presents the optimal harvesting of a stochastic two-species competitive model with Lévy noise in a polluted environment, where the Lévy noise is used to describe the sudden climate change. Due to the discontinuity of the Lévy noise, the classical optimal harvesting methods based on the explicit solution of the corresponding Fokker-Planck equation are invalid. The object of this paper is to fill up this gap and establish the optimal harvesting policy. By using of aggregation and ergodic methods, the approximation of the optimal harvesting effort and maximum expectation of sustainable yields are obtained. Numerical simulations are carried out to support these theoretical results. Our analysis shows that the Lévy noise and the mean stress measure of toxicant in organism may affect the optimal harvesting policy significantly.

The impact of timber harvest using an individual tree selection silvicultural system on the hydrology and sediment yield in a coastal California watershed

Treesearch

Arne Skaugset; Christopher G. Surfleet; Brian Dietterick

2012-01-01

There is still widespread concern regarding the environmental impact of timber harvest. This is certainly true for timber harvest activities that occur on the Swanton Pacific Ranch, the school forest for the California Polytechnic State University, located in Santa Cruz County, California. A paired watershed study was carried out to help determine the impact of...

INFINITY harvest

NASA Image and Video Library

2012-05-07

Lauren Lombard from Benjamin E. Mays Preparatory School in New Orleans enjoys lettuce she helped to harvest at the INFINITY at NASA Stennis Space Center facility May 7, 2012. The Louisiana students assisted in the first harvest of lettuce from the Controlled Environment Agriculture unit, which uses an aeroponic process that involves no soil and advance LED lighting techniques

Fog Harvesting with Harps.

PubMed

Shi, Weiwei; Anderson, Mark J; Tulkoff, Joshua B; Kennedy, Brook S; Boreyko, Jonathan B

2018-04-11

Fog harvesting is a useful technique for obtaining fresh water in arid climates. The wire meshes currently utilized for fog harvesting suffer from dual constraints: coarse meshes cannot efficiently capture microscopic fog droplets, whereas fine meshes suffer from clogging issues. Here, we design and fabricate fog harvesters comprising an array of vertical wires, which we call "fog harps". Under controlled laboratory conditions, the fog-harvesting rates for fog harps with three different wire diameters were compared to conventional meshes of equivalent dimensions. As expected for the mesh structures, the mid-sized wires exhibited the largest fog collection rate, with a drop-off in performance for the fine or coarse meshes. In contrast, the fog-harvesting rate continually increased with decreasing wire diameter for the fog harps due to efficient droplet shedding that prevented clogging. This resulted in a 3-fold enhancement in the fog-harvesting rate for the harp design compared to an equivalent mesh.

Sugarcane straw harvest effects on soil quality and plant growth: preliminary data synthesis of a multi-local project running in Brazil

NASA Astrophysics Data System (ADS)

Cherubin, Maurício; Cerri, Carlos E. P.; Feigl, Brigitte J.; Cerri, Carlos C.

2017-04-01

Brazil is the largest sugarcane producer in the world, and consequently, it is one of major players in the bioenergy production sector. Despite that, growing demands for bioenergies have raised the interest of Brazilian sugarcane industry to harvest the sugarcane straw left on the field for cellulosic ethanol production and/or bioelectricity cogeneration. However, crop residues have a key role in the soil, affecting directly or indirectly multiple soil functions and related ecosystem services. Therefore, indiscriminate straw harvest could jeopardize soil quality, decreasing its capacity to sustain plant productivity over time. In order to evaluate the potential impacts of sugarcane straw harvest on soil quality and plant growth, we are conducting since 2014 a multi-local project across central-southern Brazil, the main core of sugarcane production in the world. A wide range of soil chemical, physical and biological parameters, as well as, plant biomass production has been quantified under increasing straw harvest intensities. Our preliminary findings have showed that short-term straw harvest management did not affect total organic C stocks; however, high straw harvest led to significant reduction in labile C forms (e.g., microbial biomass C and N), and abundance of microbial communities as well. Sugarcane straw harvest affects soil nutrient cycling, since significant amount of nutrients are removed annually by straw, especially in top (green) leaves. In addition, our data show that straw acts as a thermal insulator, decreasing soil temperature amplitude and keeping soil moisture for a longer time. Straw harvest management did not affect sugarcane yields in the first two crop seasons. Based on this first synthesis of the project, we conclude that short-term sugarcane straw harvest led to soil changes, especially in more sensitive and dynamic properties, which did not affect the plant yield. However, long-term impacts should be monitored towards a better

Spectral considerations for modeling yield of canola

USDA-ARS?s Scientific Manuscript database

Conspicuous yellow flowers that are present in a Brassica oilseed crop such as canola require careful consideration when selecting a spectral index for yield estimation. This study evaluated spectral indices for multispectral sensors that correlate with the seed yield of Brassica oilseed crops. A ...

1973 Oregon timber harvest.

Treesearch

J.D. Jr. Lloyd

1974-01-01

The 1973 Oregon timber harvest of 9.36 billion board feet was 265 million board feet (2.8 percent) below the 1972 harvest. The greater portion of the decrease occurred in eastern Oregon where timber harvest dropped 9.4 percent compared with 0.9 percent in western Oregon.

Role of aquaporins in determining transpiration and photosynthesis in water-stressed plants: crop water-use efficiency, growth and yield.

PubMed

Moshelion, Menachem; Halperin, Ofer; Wallach, Rony; Oren, Ram; Way, Danielle A

2015-09-01

The global shortage of fresh water is one of our most severe agricultural problems, leading to dry and saline lands that reduce plant growth and crop yield. Here we review recent work highlighting the molecular mechanisms allowing some plant species and genotypes to maintain productivity under water stress conditions, and suggest molecular modifications to equip plants for greater production in water-limited environments. Aquaporins (AQPs) are thought to be the main transporters of water, small and uncharged solutes, and CO2 through plant cell membranes, thus linking leaf CO2 uptake from the intercellular airspaces to the chloroplast with water loss pathways. AQPs appear to play a role in regulating dynamic changes of root, stem and leaf hydraulic conductivity, especially in response to environmental changes, opening the door to using AQP expression to regulate plant water-use efficiency. We highlight the role of vascular AQPs in regulating leaf hydraulic conductivity and raise questions regarding their role (as well as tonoplast AQPs) in determining the plant isohydric threshold, growth rate, fruit yield production and harvest index. The tissue- or cell-specific expression of AQPs is discussed as a tool to increase yield relative to control plants under both normal and water-stressed conditions. © 2014 John Wiley & Sons Ltd.

Costs, yields, and revenues associated with thinning and clearcutting 60-year-old cherry-maple stands

Treesearch

Gary W. Miller; Raymond L. Sarles; Raymond L. Sarles

1986-01-01

Logging costs, product yields, and harvest revenues were determined for three thinning treatments (75, 60, and 45 percent residual stocking) and clearcutting in 60-year-old cherry-maple stands. The study area was logged by a three-man crew using chain saws and a wheeled skidder. Time study and yield data indicated that production rates and costs were similar among the...

A new harvest operation cost model to evaluate forest harvest layout alternatives

Treesearch

Mark M. Clark; Russell D. Meller; Timothy P. McDonald; Chao Chi Ting

1997-01-01

The authors develop a new model for harvest operation costs that can be used to evaluate stands for potential harvest. The model is based on felling, extraction, and access costs, and is unique in its consideration of the interaction between harvest area shapes and access roads. The scientists illustrate the model and evaluate the impact of stand size, volume, and road...

Harvesting wood for energy.

Treesearch

Rodger A. Arola; Edwin W. Miyata

1981-01-01

Illustrates the potential of harvesting wood for industrial energy, based on the results of five harvesting studies. Presents information on harvesting operations, equipment costs, and productivity. Discusses mechanized thinning of hardwoods, clearcutting of low-value stands and recovery of hardwood tops and limbs. Also includes basic information on the physical and...

Ecological impacts of energy-wood harvests: lessons from whole-tree harvesting and natural disturbance

USGS Publications Warehouse

Berger, Alaina L.; Palik, Brian; D'Amato, Anthony W.; Fraver, Shawn; Bradford, John B.; Nislow, Keith H.; King, David; Brooks, Robert T.

2013-01-01

Recent interest in using forest residues and small-diameter material for biofuels is generating a renewed focus on harvesting impacts and forest sustainability. The rich legacy of research from whole-tree harvesting studies can be examined in light of this interest. Although this research largely focused on consequences for forest productivity, in particular carbon and nutrient pools, it also has relevance for examining potential consequences for biodiversity and aquatic ecosystems. This review is framed within a context of contrasting ecosystem impacts from whole-tree harvesting because it represents a high level of biomass removal. Although whole-tree harvesting does not fully use the nonmerchantable biomass available, it indicates the likely direction and magnitude of impacts that can occur through energy-wood harvesting compared with less-intensive conventional harvesting and to dynamics associated with various natural disturbances. The intent of this comparison is to gauge the degree of departure of energy-wood harvesting from less intensive conventional harvesting. The review of the literature found a gradient of increasing departure in residual structural conditions that remained in the forest when conventional and whole-tree harvesting was compared with stand-replacing natural disturbance. Important stand- and landscape-level processes were related to these structural conditions. The consequence of this departure may be especially potent because future energy-wood harvests may more completely use a greater range of forest biomass at potentially shortened rotations, creating a great need for research that explores the largely unknown scale of disturbance that may apply to our forest ecosystems.

INFINITY harvest

NASA Image and Video Library

2012-05-07

Shania Etheridge from Benjamin E. Mays Preparatory School in New Orleans shows off the head of lettuce she harvested at the INFINITY at NASA Stennis Space Center facility May 7, 2012. The Louisiana students assisted in the first harvest of lettuce from the Controlled Environment Agriculture unit, which uses an aeroponic process that involves no soil and advance LED lighting techniques.

Microalgae harvesting techniques: A review.

PubMed

Singh, Gulab; Patidar, S K

2018-07-01

Microalgae with wide range of commercial applications have attracted a lot of attention of the researchers in the last few decades. However, microalgae utilization is not economically sustainable due to high cost of harvesting. A wide range of solid - liquid separation techniques are available for microalgae harvesting. The techniques include coagulation and flocculation, flotation, centrifugation and filtration or a combination of various techniques. Despite the importance of harvesting to the economics and energy balance, there is no universal harvesting technique for microalgae. Therefore, this review focuses on assessing technical, economical and application potential of various harvesting techniques so as to allow selection of an appropriate technology for cost effectively harvesting of microalgae from their culture medium. Various harvesting and concentrating techniques of microalgae were reviewed to suggest order of suitability of the techniques for four main microalgae applications i.e biofuel, human and animal food, high valued products, and water quality restoration. For deciding the order of suitability, a comparative analysis of various harvesting techniques based on the six common criterions (i.e biomass quality, cost, biomass quantity, processing time, species specific and toxicity) has been done. Based on the order of various techniques vis-a-vis various criteria and preferred order of criteria for various applications, order of suitability of harvesting techniques for various applications has been decided. Among various harvesting techniques, coagulation and flocculation, centrifugation and filtration were found to be most suitable for considered applications. These techniques may be used alone or in combination for increasing the harvesting efficiency. Copyright © 2018 Elsevier Ltd. All rights reserved.

[Soil seed bank in Keerqin meadow grassland under grazing and harvesting].

PubMed

Jiang, Deming; Li, Rongping; Liu, Zhimin; Yan, Qiaoling

2004-10-01

This study on the size and composition of seed bank and its relationship with vegetation showed in Keerqin meadow grassland, the density of soil seed bank was 6158 +/- 1647 grains x m(-2) under grazing and 8312 +/- 2540 grains m(-2) under harvesting. Under grazing, the seed bank was mainly composed of some dwarf and short-life annuals. The seeds of the annuals and biennials accounted for 81.66% of the seeds in seed bank. The four species with largest proportion of seed bank were Chloris virgata, Chenopodium glaucum, Digitaria cilliaris and Setaria viridis, and the proportions were 38.55%, 15.42%, 14.95%, and 9.83%, respectively. The density of perennials in soil seed bank was 1129 +/- 302 grains x m(-2). Under harvesting, the seeds of annuals and biennials accounted for 68.08% of the seed in seed bank, and the proportion of Setaria viridis was 52.7%. In the harvesting meadow grassland, the seed density of perennials was 2653 +/- 811 grains x m(-2). There was no significant correlation between the seed density in soil and the vegetation under grazing, but a significant correlation between the seed density in soil and the species abundance of vegetation under harvesting (r = 0.76, P < 0.01). The index of Shannon-Wiener and richness of grazing meadow grassland were 2.96 and 2.98, respectively, distinctly smaller than 3.10 and 5.09 of harvesting meadow, which showed that free grazing made the diversity of seed bank decrease easily.

Incorporating harvest rates into the sex-age-kill model for white-tailed deer

USGS Publications Warehouse

Norton, Andrew S.; Diefenbach, Duane R.; Rosenberry, Christopher S.; Wallingford, Bret D.

2013-01-01

appropriate sample sizes, by management unit, to estimate harvest rate parameters each year may be too expensive, assumptions of constant annual harvest rates may be necessary. However, if changes in harvest regulations or hunter behavior influence subadult male harvest rates, the PASAK model could provide an unreliable index to population changes. 

Development and Deployment of a Short Rotation Woody Crops Harvesting System Based on a Case New Holland Forage Harvester and SRC Woody Crop Header

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eisenbies, Mark; Volk, Timothy; Abrahamson, Lawrence

Biomass for biofuels, bioproducts and bioenergy can be sourced from forests, agricultural crops, various residue streams, and dedicated woody or herbaceous crops. Short rotation woody crops (SRWC), like willow and hybrid poplar, are perennial cropping systems that produce a number of environmental and economic development benefits in addition to being a renewable source of biomass that can be produced on marginal land. Both hybrid poplar and willow have several characteristics that make them an ideal feedstock for biofuels, bioproducts, and bioenergy; these include high yields that can be obtained in three to four years, ease of cultivar propagation from dormantmore » cuttings, a broad underutilized genetic base, ease of breeding, ability to resprout after multiple harvests, and feedstock composition similar to other sources of woody biomass. Despite the range of benefits associated with SRWC systems, their deployment has been restricted by high costs, low market acceptance associated with inconsistent chip quality (see below for further explanation), and misperceptions about other feedstock characteristics (see below for further explanation). Harvesting of SRWC is the largest single cost factor (~1/3 of the final delivered cost) in the feedstock supply system. Harvesting is also the second largest input of primary fossil energy in the system after commercial N fertilizer, accounting for about one third of the input. Therefore, improving the efficiency of the harvesting system has the potential to reduce both cost and environmental impact. At the start of this project, we projected that improving the overall efficiency of the harvesting system by 25% would reduce the delivered cost of SRWC by approximately $0.50/MMBtu (or about $7.50/dry ton). This goal was exceeded over the duration of this project, as noted below.« less

Effect of volunteer rice infestation on grain quality and yield of rice

USDA-ARS?s Scientific Manuscript database

Volunteer rice (Oryza sativa L.) plants arise from shattered seeds of the previous crop, which could reduce the yield of cultivated rice and the commercial value of harvested grain. Volunteer rice plants from a cultivar other than the current crop produce grains that may differ in physico-chemical t...

INFINITY harvest

NASA Image and Video Library

2012-05-07

Janice Hueschen of Innovative Imaging & Research Corp. at Stennis Space Center helps students from Benjamin E. Mays Preparatory School in New Orleans harvest lettuce at the INFINITY at NASA Stennis Space Center facility May 7, 2012. The Louisiana students assisted in the first harvest of lettuce from the Controlled Environment Agriculture unit, which uses an aeroponic process that involves no soil and advance LED lighting techniques.

Preharvest Application of Methyl Jasmonate as an Elicitor Improves the Yield and Phenolic Content of Artichoke.

PubMed

Martínez-Esplá, Alejandra; Valero, Daniel; Martínez-Romero, Domingo; Castillo, Salvador; Giménez, María José; García-Pastor, Maria Emma; Serrano, María; Zapata, Pedro Javier

2017-10-25

The effects of methyl jasmonate (MeJa) treatment as an elicitor of artichoke plants [Cynara cardunculus var. scolymus (L.) Fiori] on the yield and quality attributes of artichokes, especially those related to individual phenolic content and antioxidant activity, at two harvest dates and along storage were analyzed in this research. Plants treated gave a higher yield of artichokes in comparison to control plants, with 0.55 kg more per plant. MeJa treatment also increased artichoke quality and phenolic content in the edible fraction at harvest and during storage at 2 °C for 28 days as a result of the accumulation of hydroxycinnamic acids and luteolin derivatives. In addition, antioxidant activity was enhanced by MeJa treatment and correlated with the total phenolic content. Results suggest that MeJa foliar application could be a simple and practical tool to improve the yield and phytochemical content on artichokes, with elicitation being a cheap and environmentally friendly procedure to improve the health-beneficial effects of artichoke consumption.

Comparative analysis of solar pasteurization versus solar disinfection for the treatment of harvested rainwater.

PubMed

Strauss, André; Dobrowsky, Penelope Heather; Ndlovu, Thando; Reyneke, Brandon; Khan, Wesaal

2016-12-09

Numerous pathogens and opportunistic pathogens have been detected in harvested rainwater. Developing countries, in particular, require time- and cost-effective treatment strategies to improve the quality of this water source. The primary aim of the current study was thus to compare solar pasteurization (SOPAS; 70 to 79 °C; 80 to 89 °C; and ≥90 °C) to solar disinfection (SODIS; 6 and 8 hrs) for their efficiency in reducing the level of microbial contamination in harvested rainwater. The chemical quality (anions and cations) of the SOPAS and SODIS treated and untreated rainwater samples were also monitored. While the anion concentrations in all the samples were within drinking water guidelines, the concentrations of lead (Pb) and nickel (Ni) exceeded the guidelines in all the SOPAS samples. Additionally, the iron (Fe) concentrations in both the SODIS 6 and 8 hr samples were above the drinking water guidelines. A >99% reduction in Escherichia coli and heterotrophic bacteria counts was then obtained in the SOPAS and SODIS samples. Ethidium monoazide bromide quantitative polymerase chain reaction (EMA-qPCR) analysis revealed a 94.70% reduction in viable Legionella copy numbers in the SOPAS samples, while SODIS after 6 and 8 hrs yielded a 50.60% and 75.22% decrease, respectively. Similarly, a 99.61% reduction in viable Pseudomonas copy numbers was observed after SOPAS treatment, while SODIS after 6 and 8 hrs yielded a 47.27% and 58.31% decrease, respectively. While both the SOPAS and SODIS systems reduced the indicator counts to below the detection limit, EMA-qPCR analysis indicated that SOPAS treatment yielded a 2- and 3-log reduction in viable Legionella and Pseudomonas copy numbers, respectively. Additionally, SODIS after 8 hrs yielded a 2-log and 1-log reduction in Legionella and Pseudomonas copy numbers, respectively and could be considered as an alternative, cost-effective treatment method for harvested rainwater.

1969 Washington timber harvest.

Treesearch

Brian R. Wall

1970-01-01

Washington's timber harvest increased slightly in 1969 to a 40-year high of 7 billion board feet. This is slightly below the record timber harvest of 7.38 billion board feet established in 1829. Private timberland owners in western Washington increased their production 10.9 percent, accounting for most of the increase in the 1969 total harvest. In eastern...

Relationships between Soil and Levels of Meloidogyne incognita and Tobacco Yield and Quality.

PubMed

Barker, K R; Weeks, W W

1991-01-01

A 2-year study with six soils and four levels of Meloidogyne incognita in microplots was designed to determine the effects of these parameters on nematode activity and tobacco yield and quality. Key components under study were affected by soil, nematode level, and season (year-cultivar). In 1980, low initial nematode numbers (1,250) enhanced tobacco yield in Cecil clay loam, but caused slight to moderate yield losses in the other soils. Yield losses to M. incognita were generally greatest in sandy and muck soils. In 1980, regression analyses of the independent parameters Pi - clay-sand vs. yield gave an R(2) of 0.40. Examples of other coefficients of determination for yield vs. selected factors were root-necrosis index, 0.40; root-gall index, 0.18; root-gall index-cation exchange capacity (CEC), 0.34; root-necrosis index-CEC, 0.56; and root-necrosis index-sand-soil acidity-calcium, 0.62. In contrast, the R(2) for Pi alone versus yield in 1981 was 0.84. Soil also affected nematode reproduction with the greatest increases occurring in the sandy soils. In both years, low nematode numbers enhanced the synthesis of sugar in tobacco, whereas leaves from all other nematode treatments had low sugar levels. A low nicotine content was associated with nematode infection. Tobacco from sandy soils had a higher nicotine content than tobacco from clay soils.

Evaluation of physiological, growth and yield responses of a tropical oil crop (Brassica campestris L. var. Kranti) under ambient ozone pollution at varying NPK levels.

PubMed

Singh, Poonam; Agrawal, Madhoolika; Agrawal, Shashi Bhushan

2009-03-01

A field study was conducted to evaluate the impact of ambient ozone on mustard (Brassica campestris L. var. Kranti) plants grown under recommended and 1.5 times recommended NPK doses at a rural site of India using filtered (FCs) and non-filtered open top chambers (NFCs). Ambient mean O(3) concentration varied from 41.65 to 54.2ppb during the experiment. Plants growing in FCs showed higher photosynthetic rate at both NPK levels, but higher stomatal conductance only at recommended NPK. There were improvements in growth parameters and biomass of plants in FCs as compared to NFCs at both NPK levels with higher increments at 1.5 times recommended. Seed yield and harvest index decreased significantly only at recommended NPK in NFCs. Seed quality in terms of nutrients, protein and oil contents reduced in NFCs at recommended NPK. The application of 1.5 times recommended NPK provided protection against yield loss due to ambient O(3).

Timber harvest as the predominant disturbance regime in northeastern U.S. forests: Effects of harvest intensification

USGS Publications Warehouse

Brown, Michelle L.; Canham, Charles D.; Murphy, Lora; Donovan, Therese M.

2018-01-01

Harvesting is the leading cause of adult tree mortality in forests of the northeastern United States. While current rates of timber harvest are generally sustainable, there is considerable pressure to increase the contribution of forest biomass to meet renewable energy goals. We estimated current harvest regimes for different forest types and regions across the U.S. states of New York, Vermont, New Hampshire, and Maine using data from the U.S. Forest Inventory and Analysis Program. We implemented the harvest regimes in SORTIE‐ND, an individual‐based model of forest dynamics, and simulated the effects of current harvest regimes and five additional harvest scenarios that varied by harvest frequency and intensity over 150 yr. The best statistical model for the harvest regime described the annual probability of harvest as a function of forest type/region, total plot basal area, and distance to the nearest improved road. Forests were predicted to increase in adult aboveground biomass in all harvest scenarios in all forest type and region combinations. The magnitude of the increase, however, varied dramatically—increasing from 3% to 120% above current landscape averages as harvest frequency and intensity decreased. The variation can be largely explained by the disproportionately high harvest rates estimated for Maine as compared with the rest of the region. Despite steady biomass accumulation across the landscape, stands that exhibited old‐growth characteristics (defined as ≥300 metric tons of biomass/hectare) were rare (8% or less of stands). Intensified harvest regimes had little effect on species composition due to widespread partial harvesting in all scenarios, resulting in dominance by late‐successional species over time. Our analyses indicate that forest biomass can represent a sustainable, if small, component of renewable energy portfolios in the region, although there are tradeoffs between carbon sequestration in forest biomass and sustainable

Stover removal effects on continuous corn yield and nitrogen use efficiency under irrigation

USDA-ARS?s Scientific Manuscript database

Corn (Zea mays L.) residue or stover is harvested as supplemental feed for livestock and is a primary feedstock for cellulosic biofuels. Limited information is available on corn residue removal effects on grain yield under different nitrogen (N) fertilizer rates, irrigation rates and amelioration pr...

Harvest and dynamics of duck populations

USGS Publications Warehouse

Sedinger, James S.; Herzog, Mark P.

2012-01-01

The role of harvest in the dynamics of waterfowl populations continues to be debated among scientists and managers. Our perception is that interested members of the public and some managers believe that harvest influences North American duck populations based on calls for more conservative harvest regulations. A recent review of harvest and population dynamics of North American mallard (Anas platyrhynchos) populations (Pöysä et al. 2004) reached similar conclusions. Because of the importance of this issue, we reviewed the evidence for an impact of harvest on duck populations. Our understanding of the effects of harvest is limited because harvest effects are typically confounded with those of population density; regulations are typically most liberal when populations are greatest. This problem also exists in the current Adaptive Harvest Management Program (Conn and Kendall 2004). Consequently, even where harvest appears additive to other mortality, this may be an artifact of ignoring effects of population density. Overall, we found no compelling evidence for strong additive effects of harvest on survival in duck populations that could not be explained by other factors.

[Yield and chemical composition of the vegetal parts of the amaranth (Amaranthus hypochondriacus, L.) at different physiological stages].

PubMed

Alfaro, M A; Martínez, A; Ramírez, R; Bressani, R

1987-03-01

The genus Amaranthus comprises species which, consumed as vegetables, provide essential nutrients to man; they also have a high acceptability among the population. These two factors justify the need to increase their cultivation. Therefore, the purpose of this research was to establish the most adequate physiological state of maturity, to harvest the leaves for human consumption. The field experiment utilized a randomized block design with three treatments and eight replications. These treatments consisted in harvesting the plants at 25, 40 and 60 days after emergence of the seedlings, samples which served to evaluate: plant height, number of leaves, leaf surface area, gross weight (leaves and stems), net weight (leaves), green matter and dry matter yield, as well as protein. The chemical composition of the harvested material was evaluated also in terms of moisture, protein, crude fiber, ether extract, ash, carbohydrate, calcium, phosphorus, iron, beta-carotene and oxalates. The results obtained in the agronomic study were subjected to analysis of variance for the respective design, with significant differences found between treatments for all the variables studied. In its turn, the results of the chemical analysis were analyzed by a completely randomized design, with significant differences obtained for most of the variables studied, except for ether extract, calcium, iron and oxalates. From the nutritional point of view, the first harvest was the most acceptable due to the chemical composition of the plant, in particular protein (29.5%), beta-carotene (33.7 mg%), calcium (2,356.1 mg%), phosphorus (759.1 mg%) and due to its low crude fiber content, only 11.1 g%. It did not occur so from the agronomic point of view, since during this stage, very low yields of green matter (575.9 kg/ha), dry matter (66.6 kg/ha) and protein (19.7 kg/ha) were obtained. At the second harvest, besides obtaining adequate yields of green matter (6,530.4 kg/ha), dry matter (681.8 kg

1971 Washington timber harvest.

Treesearch

Brian R. Wall

1972-01-01

Washington's 1971 timber harvest of 6.45 billion board feet was nearly the same as the 1970 harvest level. The total timber harvest on public lands increased nearly 4 percent with a 30-percent increase in eastern Washington more than offsetting a 5-percent decline in western Washington. Part of the increase in eastern Washington reflects salvage of a large volume...

Patterns of Cereal Yield Growth across China from 1980 to 2010 and Their Implications for Food Production and Food Security

PubMed Central

Li, Xiaoyun; Liu, Nianjie; You, Liangzhi; Ke, Xinli; Liu, Haijun; Huang, Malan; Waddington, Stephen R.

2016-01-01

After a remarkable 86% increase in cereal production from 1980 to 2005, recent crop yield growth in China has been slow. County level crop production data between 1980 and 2010 from eastern and middle China were used to analyze spatial and temporal patterns of rice, wheat and maize yield in five major farming systems that include around 90% of China's cereal production. Site-specific yield trends were assessed in areas where those crops have experienced increasing yield or where yields have stagnated or declined. We find that rice yields have continued to increase on over 12.3 million hectares (m. ha) or 41.8% of the rice area in China between 1980 and 2010. However, yields stagnated on 50% of the rice area (around 14.7 m. ha) over this time period. Wheat yields increased on 13.8 m. ha (58.2% of the total harvest area), but stagnated on around 3.8 m. ha (15.8% of the harvest area). Yields increased on a smaller proportion of the maize area (17.7% of harvest area, 5.3 m. ha), while yields have stagnated on over 54% (16.3 m. ha). Many parts of the lowland rice and upland intensive sub-tropical farming systems were more prone to stagnation with rice, the upland intensive sub-tropical system with wheat, and maize in the temperate mixed system. Large areas where wheat yield continues to rise were found in the lowland rice and temperate mixed systems. Land and water constraints, climate variability, and other environmental limitations undermine increased crop yield and agricultural productivity in these systems and threaten future food security. Technology and policy innovations must be implemented to promote crop yields and the sustainable use of agricultural resources to maintain food security in China. In many production regions it is possible to better match the crop with input resources to raise crop yields and benefits. Investments may be especially useful to intensify production in areas where yields continue to improve. For example, increased support to maize

Hydrological impact of rainwater harvesting in the Modder river basin of central South Africa

NASA Astrophysics Data System (ADS)

Welderufael, W. A.; Woyessa, Y. E.; Edossa, D. C.

2011-05-01

Along the path of water flowing in a river basin are many water-related human interventions that modify the natural systems. Rainwater harvesting is one such intervention that involves harnessing of water in the upstream catchment. Increased water usage at upstream level is an issue of concern for downstream water availability to sustain ecosystem services. The upstream Modder River basin, located in a semi arid region in the central South Africa, is experiencing intermittent meteorological droughts causing water shortages for agriculture, livestock and domestic purpose. To address this problem a technique was developed for small scale farmers with the objective of harnessing rainwater for crop production. However, the hydrological impact of a wider adoption of this technique by farmers has not been well quantified. In this regard, the SWAT hydrological model was used to simulate the hydrological impact of such practices. The scenarios studied were: (1) Baseline scenario, based on the actual land use of 2000, which is dominated by pasture (combination of natural and some improved grass lands) (PAST); (2) Partial conversion of Land use 2000 (PAST) to conventional agriculture (Agri-CON); and (3) Partial conversion of Land use 2000 (PAST) to in-field rainwater harvesting which was aimed at improving the precipitation use efficiency (Agri-IRWH). SWAT was calibrated using observed daily mean stream flow data of a sub-catchment (419 km2) in the study area. SWAT performed well in simulating the stream flow giving Nash and Sutcliffe (1970) efficiency index of 0.57 for the monthly stream flow calibration. The simulated water balance results showed that the highest peak mean monthly direct flow was obtained on Agri-CON land use (18 mm), followed by PAST (12 mm) and Agri-IRWH land use (9 mm). These were 19 %, 13 % and 11 % of the mean annual rainfall, respectively. The Agri-IRWH scenario reduced direct flow by 38 % compared to Agri-CON. On the other hand it was found that the

Changes in Carbon Storage and Net Carbon Exchange After a Shelterwood Harvest at Howland Forest, Maine

NASA Astrophysics Data System (ADS)

Scott, N. A.; Rodrigues, C. A.; Hughes, H.; Lee, J. T.; Davidson, E. A.; Dail, D. B.; Goltz, S. M.; Malerba, P.; Hollinger, D. Y.

2003-12-01

While many forests are actively sequestering carbon, little research has examined the direct effects of forest management practices on carbon sequestration. This is a critical issue in North America, where a large proportion of forests are managed. At the Howland Forest in Maine, we are using eddy covariance, biometric techniques and modeling to evaluate changes in carbon storage following a shelterwood cut that removed just under 30% of aboveground biomass. This management regime is becoming increasingly common throughout the region. Prior to harvest, the stand contained about 76 Mg C ha-1 (30 m2ha-1 basal area) in above- and below-ground live biomass. Harvesting removed about 15 Mg C ha-1 (SEM=2.1), and created about 5.3 Mg C ha-1 (SEM=1.1) of aboveground and 5.2 Mg C ha-1 (SEM=0.7) of root/stump detritus. Leaf-area index and litterfall declined by about 40% with harvest. Approximately half of the harvested wood was used for paper products (half-life of 3.5 years) and half for longer-lived wood products (half-life of 45 years). In a nearby, unharvested stand, eddy covariance measurements indicated that net ecosystem exchange (NEE) averages about 1.8 Mg C ha-1 y-1. A comparison of NEE at unharvested and harvested stands, both pre- and post-harvest, indicated that NEE declined following the harvest by about 18%, which is less than expected based on basal area and LAI changes. Both daily uptake and nocturnal respiration declined after harvest. Soil respiration declined slightly with harvest, suggesting no major soil C loss after harvest; harvesting had little effect on soil moisture and temperature. When decay of paper and wood products is included in a preliminary carbon budget, we predict that the forest will be a net C source to the atmosphere for at least 5 years, assuming pre-harvest growth rates of trees. How quickly the carbon balance becomes positive will depend largely on whether post-harvest tree growth rates increase.

Large Area Crop Inventory Experiment (LACIE). Feasibility of assessing crop condition and yield from LANDSAT data

NASA Technical Reports Server (NTRS)

1978-01-01

The author has identified the following significant results. Yield modelling for crop production estimation derived a means of predicting the within-a-year yield and the year-to-year variability of yield over some fixed or randomly located unit of area. Preliminary studies indicated that the requirements for interpreting LANDSAT data for yield may be sufficiently similar to those of signature extension that it is feasible to investigate the automated estimation of production. The concept of an advanced yield model consisting of both spectral and meteorological components was endorsed. Rationale for using meteorological parameters originated from known between season and near harvest dynamics in crop environmental-condition-yield relationships.

Influence of Phenological Stages on Yield and Quality of Oregano (Origanum vulgare L.) Under the Agroclimatic Condition of Doon Valley (Uttarakhand)

PubMed Central

Chauhan, N. K.; Singh, S.; Haider, S. Z.; Lohani, H.

2013-01-01

A field experiment was conducted under the agroclimatic conditions of Doon valley, in order to determine the effects of phenological stages on herbage yield and quality of oil in oregano (Origanum vulgare L.). Plants were harvested in five phenological stages, i.e. early vegetative, late vegetative, flower initiation, full bloom, and fruit set stages. Results showed the significant effects of phenological stages on herbage, yield, and quality of oregano. Harvesting at full bloom stage showed better results in terms of herbage and oil yield. The quality of essential oil was evaluated using GC and GC/MS. Thymol content was rich in all the stages (46.90-62.26%) followed by γ-terpinene (1.11-11.75%) and p-cymene (3.11-5.32%). PMID:24302806

Donor body mass index is an important factor that affects peripheral blood progenitor cell yield in healthy donors after mobilization with granulocyte-colony-stimulating factor.

PubMed

Chen, Jian; Burns, Kevin M; Babic, Aleksandar; Carrum, George; Kennedy, Martha; Segura, Francisco J; Garcia, Salvador; Potts, Sandra; Leveque, Christopher

2014-01-01

The use of hematopoietic progenitor cell (HPC) transplantation has rapidly expanded in recent years. Currently, several sources of HPCs are available for transplantation including peripheral blood HPCs (PBPCs), cord blood cells, and marrow cells. Of these, PBPC collection has become the major source of HPCs. An important variable in PBPC collection is the response to PBPC mobilization, which varies significantly and sometime causes mobilization failure. A retrospective study of 69 healthy donors who underwent PBPC donation by leukapheresis was performed. All of these donors received 10 μg/kg/day or more granulocyte-colony-stimulating factor (G-CSF) for 5 days before PBPC harvest. Donor factors were evaluated and correlated with mobilization responses, as indicated by the precollection CD34 count (pre-CD34). Donors with a pre-CD34 of more than 100 × 10(6) /L had higher body mass index (BMI) compared with donors whose pre-CD34 was 38 × 10(6) to 99 × 10(6) /L or less than 38 × 10(6) /L (32.0 ± 1.04 kg/m(2) vs. 28.7 ± 0.93 kg/m(2) vs. 25.9 ± 1.27 kg/m(2) , respectively; p < 0.05). In addition, donors with high BMIs had higher pre-CD34 on a per-kilogram-of-body-weight basis compared with donors with low BMIs. BMI is an important factor that affects donor's response to mobilization and consequently the HPC yield. This effect may be due to a relatively high dose of G-CSF administered to donors with higher BMI or due to the presence of unknown intrinsic factors affecting mobilization that correlate with the amount of adipose tissue in each donor. © 2013 American Association of Blood Banks.

Wastewater polishing by a channelized macrophyte-dominated wetland and anaerobic digestion of the harvested phytomass.

PubMed

Cohen, Michael F; Hare, Caden; Kozlowski, John; McCormick, Rachel S; Chen, Lily; Schneider, Linden; Parish, Meghan; Knight, Zane; Nelson, Timothy A; Grewell, Brenda J

2013-01-01

Constructed wetlands (CW) offer a mechanism to meet increasingly stringent regulatory standards for wastewater treatment while minimizing energy inputs. Additionally, harvested wetland phytomass subjected to anaerobic digestion can serve as a source of biogas methane. To investigate CW wastewater polishing activities and potential energy yield we constructed a pair of secondary wastewater-fed channelized CW modules designed to retain easily harvestable floating aquatic vegetation and maximize exposure of water to roots and sediment. Modules that were regularly harvested averaged a nitrate removal rate of 1.1 g N m(-2) d(-1); harvesting, sedimentation and gasification were responsible for 30.5%, 8.0% and 61.5% of the N losses, respectively. Selective harvesting of a module to maintain dominance of filamentous algae had no effect on nitrate removal rate but lowered productivity by one-half. The average monthly productivity for unselectively harvested modules was 9.3 ± 1.7 g dry wt. m(-2) d(-1) (±SE). Cessation of harvesting in one module resulted in a significant increase in nitrate removal rate and decrease in phosphate removal rate. Compared to the influent, the effluent of the harvested module had significantly lower levels of estrogenic activity, as determined by a quantitative PCR-based juvenile trout bioassay, and significantly lower densities of E. coli. In mixed vertical-flow reactors anaerobic co-digestion of equal dry weight proportions of harvested aquatic vegetation, wine yeast lees and dairy manure was greatly improved when the manure was replaced with the crude glycerol by-product of biodiesel production. Remaining solids were vermicomposted for use as a soil amendment. Our results indicate that incorporation of constructed wetlands into an integrated treatment system can simultaneously enhance the economic and energetic feasibility of wastewater and organic waste treatment processes.

Evaluation of maize inbred lines for resistance to pre-harvest aflatoxin and fumonisin contamination in the field

USDA-ARS?s Scientific Manuscript database

Two important mycotoxins, aflatoxin and fumonisin, are among the most potent naturally occurring carcinogens, contaminating maize (Zea mays L.) and affecting the crop yield and quality. Resistance of maize to pre-harvest mycotoxin contamination, specifically aflatoxin produced by Aspergillus flavus ...

Using magnetic materials to harvest microalgal biomass: evaluation of harvesting and detachment efficiency.

PubMed

Zhu, L-D; Hiltunen, Erkki; Li, Zhaohua

2017-12-15

Using naked iron oxide (Fe 3 O 4 ) and yttrium iron oxide (Y 3 Fe 5 O 12 ) nanoparticles as flocculants, the harvesting efficiency of Chlorella vulgaris biomass was investigated. The harvesting process includes two steps, which are the separation of microalgae from the culture solution with the magnetic nanoparticles and then the separation of the algae from the magnetic nanoparticles. The optimal dosages and pH values for the magnetic harvesting of microalgal biomass were determined. Results showed that Y 3 Fe 5 O 12 nanoparticles were more efficient in microalgal biomass harvesting than Fe 3 O 4 nanoparticles. In an effort to achieve more than 90% of harvesting efficiency, optimal dosages for Fe 3 O 4 and Y 3 Fe 5 O 12 to harvest microalgal biomass were 10 and 2.5 g/L, while the appropriate pH values were 6.2 and 7.3, respectively. The harvesting efficiency of Fe 3 O 4 and Y 3 Fe 5 O 12 nanoparticles increased as the pH value decreased. The experimental results also showed that under a higher pH value Fe 3 O 4 nanoparticles were much easier to be separated from the flocs than Y 3 Fe 5 O 12 . 62.9% of Fe 3 O 4 nanoparticles could be de-attached from the aggregates, when the floc pH value reached 12.3.

1968 Oregon timber harvest.

Treesearch

Brian R. Wall

1969-01-01

Oregon's 1968 timber harvest of 9.74 billion board feet was the largest since 1952, when a record 9.80 billion board feet was produced. Public agencies' harvests increased 25.0 percent in western Oregon and 4.1 percent in eastern Oregon for a total increase of 19.1 percent, 864.9 million board feet above the public harvest in 1967. National Forests had the...

1967 Oregon timber harvest.

Treesearch

Brian R. Wall

1968-01-01

Oregon's timber harvest was 8.4 billion board feet in 1967, 6.3 percent below the 1966 harvest. The total private harvest declined 7 percent in 1967 with a 153-million-board-foot (4.3-percent) decrease in western Oregon and a 138-million-board-foot (22.7-percent) drop in eastern Oregon. Forest industries had the greatest decline in production of all owners; their...

1967 Washington timber harvest.

Treesearch

Brian R. Wall

1968-01-01

Washington's 1967 timber harvest declined to 5.9 billion board feet, 2.3 percent below the 1966 harvest. The cut on public lands remained about the same as in 1966 with a 6.7-percent increase in public cut in eastern Washington, offsetting a 2.2-percent decrease in western Washington. The Indian lands had the greatest increase in harvest, up 35 million board feet...

1970 Washington timber harvest.

Treesearch

Brian R. Wall

1971-01-01

Washington's 1970 timber harvest of 6.46 billion board feet was 7.8 percent below the near record harvest of 7 billion board feet established in 1969. Timber harvests on all public lands declined 13 percent with a 9.0-percent reduction in western Washington and a 22.9-percent drop in eastern Washington. State lands led the decline in public production with a 142-...

Real-time yield estimation based on deep learning

NASA Astrophysics Data System (ADS)

Rahnemoonfar, Maryam; Sheppard, Clay

2017-05-01

Crop yield estimation is an important task in product management and marketing. Accurate yield prediction helps farmers to make better decision on cultivation practices, plant disease prevention, and the size of harvest labor force. The current practice of yield estimation based on the manual counting of fruits is very time consuming and expensive process and it is not practical for big fields. Robotic systems including Unmanned Aerial Vehicles (UAV) and Unmanned Ground Vehicles (UGV), provide an efficient, cost-effective, flexible, and scalable solution for product management and yield prediction. Recently huge data has been gathered from agricultural field, however efficient analysis of those data is still a challenging task. Computer vision approaches currently face diffident challenges in automatic counting of fruits or flowers including occlusion caused by leaves, branches or other fruits, variance in natural illumination, and scale. In this paper a novel deep convolutional network algorithm was developed to facilitate the accurate yield prediction and automatic counting of fruits and vegetables on the images. Our method is robust to occlusion, shadow, uneven illumination and scale. Experimental results in comparison to the state-of-the art show the effectiveness of our algorithm.

Erosion and soil displacement related to timber harvesting in northwestern California, U.S.A.

Treesearch

R.M. Rice; D.J. Furbish

1984-01-01

The relationship between measures of site disturbance and erosion resulting from timber harvest was studied by regression analyses. None of the 12 regression models developed and tested yielded a coefficient of determination (R2) greater than 0.60. The results indicated that the poor fits to the data were due, in part, to unexplained qualitative...

Banking and use of glycerol preserved full-thickness skin allograft harvested from body contouring procedures.

PubMed

Zidan, Serag M; Eleowa, Samy A

2014-06-01

The use of glycerol preserved skin allograft (GPA) became a main stay in burn treatment. However, harvesting of cadaveric skin is not yet legalized in many countries including Egypt. To estimate the feasibility of using skin harvested from body contouring procedures as a source of GPA and its clinical efficacy. Skin harvested from body contouring procedures done in Al-Azhar university hospitals was preserved by glycerolization and used in management of burn and complicated wounds. In the period between February 2012 and February 2013 skin was harvested from 24 abdomenoplasty cases, 6 bilateral breast reduction cases, and 1 case of thigh lift done in Al-Azhar university hospitals. This yielded about 22,000 cm(2) of skin preserved by glycerolization. This GPA was used in 15 excised burn wounds, in 9 cases of chronic burn wounds, and in 6 complicated wounds. Partial graft loss occurred in 3 cases and total graft loss occurred in 1 case. The glycerolized full-thickness skin harvested from body contouring procedures is clinically effective in burn and wound management. In the presence of regional coordination, it can serve as an abundant source for skin banking in where cadaveric skin use is not legalized. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

Carbon balance in bioregenerative life support systems: some effects of system closure, waste management, and crop harvest index

NASA Technical Reports Server (NTRS)

Wheeler, Raymond M.

2003-01-01

In Advanced Life Support (ALS) systems with bioregenerative components, plant photosynthesis would be used to produce O2 and food, while removing CO2. Much of the plant biomass would be inedible and hence must be considered in waste management. This waste could be oxidized (e.g., incinerated or aerobically digested) to resupply CO2 to the plants, but this would not be needed unless the system were highly closed with regard to food. For example, in a partially closed system where some of the food is grown and some is imported, CO2 from oxidized waste when combined with crew and microbial respiration could exceed the CO2 removal capability of the plants. Moreover, it would consume some O2 produced from photosynthesis that could have been used by the crew. For partially closed systems it would be more appropriate to store or find other uses for the inedible biomass and excess carbon, such as generating soils or growing woody plants (e.g., dwarf fruit trees). Regardless of system closure, high harvest crops (i.e., crops with a high edible to total biomass ratio) would increase food production per unit area and O2 yields for systems where waste biomass is oxidized to recycle CO2. Such interlinking effects between the plants and waste treatment strategies point out the importance of oxidizing only that amount of waste needed to optimize system performance. Published by Elsevier Science Ltd on behalf of COSPAR.

Carbon balance in bioregenerative life support systems: some effects of system closure, waste management, and crop harvest index.

PubMed

Wheeler, Raymond M

2003-01-01

In Advanced Life Support (ALS) systems with bioregenerative components, plant photosynthesis would be used to produce O2 and food, while removing CO2. Much of the plant biomass would be inedible and hence must be considered in waste management. This waste could be oxidized (e.g., incinerated or aerobically digested) to resupply CO2 to the plants, but this would not be needed unless the system were highly closed with regard to food. For example, in a partially closed system where some of the food is grown and some is imported, CO2 from oxidized waste when combined with crew and microbial respiration could exceed the CO2 removal capability of the plants. Moreover, it would consume some O2 produced from photosynthesis that could have been used by the crew. For partially closed systems it would be more appropriate to store or find other uses for the inedible biomass and excess carbon, such as generating soils or growing woody plants (e.g., dwarf fruit trees). Regardless of system closure, high harvest crops (i.e., crops with a high edible to total biomass ratio) would increase food production per unit area and O2 yields for systems where waste biomass is oxidized to recycle CO2. Such interlinking effects between the plants and waste treatment strategies point out the importance of oxidizing only that amount of waste needed to optimize system performance. Published by Elsevier Science Ltd on behalf of COSPAR.

Carbon balance in bioregenerative life support systems: Some effects of system closure, waste management, and crop harvest index

NASA Astrophysics Data System (ADS)

Wheeler, Raymond M.

In Advanced Life Support (ALS) systems with bioregenerative components, plant photosynthesis would be used to produce O2 and food, while removing CO2. Much of the plant biomass would be inedible and hence must be considered in waste management. This waste could be oxidized (e.g., incinerated or aerobically digested) to resupply CO2 to the plants, but this would not be needed unless the system were highly closed with regard to food. For example, in a partially closed system where some of the food is grown and some is imported, CO2 from oxidized waste when combined with crew and microbial respiration could exceed the CO2 removal capability of the plants. Moreover, it would consume some O2 produced from photosynthesis that could have been used by the crew. For partially closed systems it would be more appropriate to store or find other uses for the inedible biomass and excess carbon, such as generating soils or growing woody plants (e.g., dwarf fruit trees). Regardless of system closure, high harvest crops (i.e., crops with a high edible to total biomass ratio) would increase food production per unit area and O2 yields for systems where waste biomass is oxidized to recycle CO2. Such interlinking effects between the plants and waste treatment strategies point out the importance of oxidizing only that amount of waste needed to optimize system performance.

Potential effect of atmospheric warming on grapevine phenology and post-harvest heat accumulation across a range of climates

NASA Astrophysics Data System (ADS)

Hall, Andrew; Mathews, Adam J.; Holzapfel, Bruno P.

2016-09-01

Carbohydrates are accumulated within the perennial structure of grapevines when their production exceeds the requirements of reproduction and growth. The period between harvest and leaf-fall (the post-harvest period) is a key period for carbohydrate accumulation in relatively warmer grape-growing regions. The level of carbohydrate reserves available for utilisation in the following season has an important effect on canopy growth and yield potential and is therefore an important consideration in vineyard management. In a warming climate, the post-harvest period is lengthening and becoming warmer, evidenced through studies in wine regions worldwide that have correlated recent air temperature increases with changing grapevine phenology. Budbreak, flowering, veraison, and harvest have all been observed to be occurring earlier than in previous decades. Additionally, the final stage of the grapevine phenological cycle, leaf-fall, occurs later. This study explored the potential for increased post-harvest carbohydrate accumulation by modelling heat accumulation following harvest dates for the recent climate (1975-2004) and two warmer climate projections with mean temperature anomalies of +1.26 and +2.61 °C. Summaries of post-harvest heat accumulation between harvest and leaf-fall were produced for each of Australia's Geographical Indications (wine regions) to provide comparisons from the base temperatures to projected warmer conditions across a range of climates. The results indicate that for warmer conditions, all regions observe earlier occurring budbreak and harvest as well as increasing post-harvest growing degree days accumulation before leaf-fall. The level of increase varies depending upon starting climatic condition, with cooler regions experiencing the greatest change.

Machine to harvest slash, brush, and thinnings for fuel and fiber- a concept

Treesearch

P. Koch; D.W. McKenzie

1976-01-01

It is proposed that biomass from noncommercial thinnings, and from logging slash residual after harvest, be hogged and recovered for fuel and fiber. Such a procedure might yield two dividends of biomass totalling as much as 90,000 kg per ha (40 tons per acre, green weight basis) from each rotation of southern pine. For sites deficient in organic matter, it is...

Machine to harvest slash, brush, and thinnings for fuel and fiber - a concept

Treesearch

Peter Koch; Dan W. McKenzie

1976-01-01

It is proposed that biomass from non-commercial thinnings, and from logging slash residual after harvest, be lhogged and recovered for fuel and fiber. Such a procedure might yield two dividends of biomass totalling as much as 90,000 kg per ha (40 tons per acre, gree weight basis) from each rotation of southern pine. For sites deficient in organic matter, it is...

1969 Oregon timber harvest.

Treesearch

Brian R. Wall

1970-01-01

The 1969 Oregon timber harvest of 9.15 billion board feet was 6.1 percent below the 1968 16-year peak of 9.74 billion board feet. In western Oregon, the 1969 harvest was down 9.1 percent with public production and private production off 10.8 and 7.2 percent, respectively. By contrast, log harvest in eastern Oregon rose 5 percent, with private production up 13.2 percent...

1966 Oregon timber harvest.

Treesearch

Brian R. Wall

1967-01-01

The 1966 Oregon timber harvest totaled 8.9 billion board feet, 5 percent less than the harvest in 1965. During 1966, the total public timber harvest declined 10 percent to 4.8 billion board feet. The uncut volume of public timber under contract at the end of 1966 was 7.6 billion board feet, up 1.3 billion board feet from 1965's year end total. National Forest...

1966 Washington timber harvest.

Treesearch

Brian R. Wall

1967-01-01

The 1966 Washington timber harvest of 6.1 billion board feet was 6.8 percent below the 1965 level. This was the first decline since 1961. In part, the lower harvest in 1966 was due to completion of salvage logging of the 1962 blowdown. The volume of dead timber salvaged in 1966 was only 6 percent of the total, compared with 15 percent in 1965. The live timber harvest...

Sustaining high-energy orbits of bi-stable energy harvesters by attractor selection

NASA Astrophysics Data System (ADS)

Udani, Janav P.; Arrieta, Andres F.

2017-11-01

Nonlinear energy harvesters have the potential to efficiently convert energy over a wide frequency range; however, difficulties in attaining and sustaining high-energy oscillations restrict their applicability in practical scenarios. In this letter, we propose an actuation methodology to switch the state of bi-stable harvesters from the low-energy intra-well configuration to the coexisting high-energy inter-well configuration by controlled phase shift perturbations. The strategy is designed to introduce a change in the system state without creating distinct metastable attractors by exploiting the basins of attraction of the coexisting stable attractors. Experimental results indicate that the proposed switching strategy yields a significant improvement in energy transduction capabilities, is highly economical, enabling the rapid recovery of energy spent in the disturbance, and can be practically implemented with widely used low-strain piezoelectric transducers.

Self-assembled nanoscale DNA-porphyrin complex for artificial light harvesting.

PubMed

Woller, Jakob G; Hannestad, Jonas K; Albinsson, Bo

2013-02-20

Mimicking green plants' and bacteria's extraordinary ability to absorb a vast number of photons and harness their energy is a longstanding goal in artificial photosynthesis. Resonance energy transfer among donor dyes has been shown to play a crucial role on the overall transfer of energy in the natural systems. Here, we present artificial, self-assembled, light-harvesting complexes consisting of DNA scaffolds, intercalated YO-PRO-1 (YO) donor dyes and a porphyrin acceptor anchored to a lipid bilayer, conceptually mimicking the natural light-harvesting systems. A model system consisting of 39-mer duplex DNA in a linear wire configuration with the porphyrin attached in the middle of the wire is primarily investigated. Utilizing intercalated donor fluorophores to sensitize the excitation of the porphyrin acceptor, we obtain an effective absorption coefficient 12 times larger than for direct excitation of the porphyrin. On the basis of steady-state and time-resolved emission measurements and Markov chain simulations, we show that YO-to-YO resonance energy transfer substantially contributes to the overall flow of energy to the porphyrin. This increase is explained through energy migration along the wire allowing the excited state energy to transfer to positions closer to the porphyrin. The versatility of DNA as a structural material is demonstrated through the construction of a more complex, hexagonal, light-harvesting scaffold yielding further increase in the effective absorption coefficient. Our results show that, by using DNA as a scaffold, we are able to arrange chromophores on a nanometer scale and in this way facilitate the assembly of efficient light-harvesting systems.

Hardwood Regrowth and Yields on Bottomland Clay Soil Following Clearcutting

Treesearch

Roger M. Krinard; Robert L. Johnson

1986-01-01

Five years of regrowth of a clearcut hardwood stand on the Delta Experimental Forest in Mississippi were evaluated to determine growth and development and biomass yields. Dry weight mean annual increments for years 1 through 5 following harvesting of an 1 l-year-old hardwood stand on Sharkey clay soil were 0.6, 1.9, 2.4, 3.5, and 3.2 tons per acre per year,...

The impact of lignin downregulation on alfalfa yield, chemical composition, and in vitro gas production.

PubMed

Getachew, Girma; Laca, Emilio A; Putnam, Daniel H; Witte, Dave; McCaslin, Mark; Ortega, Kara P; DePeters, Edward J

2018-02-06

Lignin is a complex, phenolic polymer found in plant cell walls that is essential for mechanical support, water and mineral transport, and defense in vascular plants. Over ten different enzymes play a role in the synthesis of lignin in plants. Suppression of any one enzyme or combinations of these enzymes may change the concentration and composition of lignin in the genetically transformed plants. Two lines of alfalfa that were downregulated for caffeoyl coenzyme A O-methyltransferase were used to assess the impact of lignin downregulation on chemical composition and fermentation rate and extent using an in vitro gas production technique. A total of 64 samples consisting of two reduced lignin (RL) and two controls (CL), four field replicates, two cutting intervals (CIs; 28 and 35 days), and two cuts (Cut-1 and Cut-3) were used. No differences were detected in yield, crude protein, neutral detergent fiber (aNDF), and acid detergent fiber between the lines when harvested at the 28-day CI. The acid detergent lignin (ADL) concentration in RL alfalfa lines was significantly (P < 0.001) lower than in the CL. In alfalfa harvested at the 35-day CI, the RL alfalfa resulted in lower (P < 0.001) yield than CL. RL alfalfa lines had 24% and 22% lower (P < 0.001) ADL in Cut-1 and Cut-3 respectively than CL lines. The in vitro dry matter digestibility and aNDF digestibility (both as determined by the near-infrared reflectance method) were greater (P < 0.001) in RL than in CL lines harvested at the 35-day CI. In alfalfa harvested at the 35-day CI, extent of in vitro gas production and metabolizable energy content were greater in RL than in CL alfalfa. RL lines had 3.8% indigestible aNDF per unit ADL, whereas CL had 3.4% (P < 0.01). The positive effect of lignin downregulation was more pronounced when intervals between harvests were longer (35-day CI compared with the 28-day CI). Lignin downregulation in alfalfa offers an opportunity to extend harvesting time

Advancements in Cotton Harvesting Research

USDA-ARS?s Scientific Manuscript database

Cotton harvesting research within USDA ARS is focused on improving harvest productivity, cotton quality, and producer profitability. In recent years, our work has encompassed efforts to improve both spindle picker and brush-roll stripper harvesting systems. Specifically, work with cotton pickers i...

"Erosion and soil displacement related to timber harvesting in northwestern California, U.S.A."

Treesearch

R. M. Rice; D. J. Furbish

1984-01-01

The relationship between measures of site disturbance and erosion resulting from timber harvest was studied by regression analyses. None of the 12 regression models developed and tested yielded a coefficient of determination (R 2) greater than 0.60. The results indicated that the poor fits to the data were due, in part, to unexplained qualitative differences in...

Nonlinear energy harvesting.

PubMed

Cottone, F; Vocca, H; Gammaitoni, L

2009-02-27

Ambient energy harvesting has been in recent years the recurring object of a number of research efforts aimed at providing an autonomous solution to the powering of small-scale electronic mobile devices. Among the different solutions, vibration energy harvesting has played a major role due to the almost universal presence of mechanical vibrations. Here we propose a new method based on the exploitation of the dynamical features of stochastic nonlinear oscillators. Such a method is shown to outperform standard linear oscillators and to overcome some of the most severe limitations of present approaches. We demonstrate the superior performances of this method by applying it to piezoelectric energy harvesting from ambient vibration.

High temperature energy harvesters utilizing ALN/3C-SiC composite diaphragms

NASA Astrophysics Data System (ADS)

Lai, Yun-Ju; Li, Wei-Chang; Felmetsger, Valery V.; Senesky, Debbie G.; Pisano, Albert P.

2014-06-01

Microelectromechanical systems (MEMS) energy harvesting devices aiming at powering wireless sensor systems for structural health monitoring in harsh environments are presented. For harsh environment wireless sensor systems, sensor modules are required to operate at elevated temperatures (> 250°C) with capabilities to resist harsh chemical conditions, thereby the use of battery-based power sources becomes challenging and not economically efficient if considering the required maintenance efforts. To address this issue, energy harvesting technology is proposed to replace batteries and provide a sustainable power source for the sensor systems towards autonomous harsh environment wireless sensor networks. In particular, this work demonstrates a micromachined aluminum nitride/cubic silicon carbide (AlN/3C-SiC) composite diaphragm energy harvester, which enables high temperature energy harvesting from ambient pulsed pressure sources. The fabricated device yields an output power density of 87 μW/cm2 under 1.48-psi pressure pulses at 1 kHz while connected to a 14.6-kΩ load resistor. The effects of pulse profile on output voltage have been studied, showing that the output voltage can be maximized by optimizing the diaphragm resonance frequency based on specific pulse characteristics. In addition, temperature dependence of the diaphragm resonance frequency over the range of 20°C to 600°C has been investigated and the device operation at temperatures as high as 600°C has been verified.

Phenotyping of field-grown wheat in the UK highlights contribution of light response of photosynthesis and flag leaf longevity to grain yield.

PubMed

Carmo-Silva, Elizabete; Andralojc, P John; Scales, Joanna C; Driever, Steven M; Mead, Andrew; Lawson, Tracy; Raines, Christine A; Parry, Martin A J

2017-06-15

Improving photosynthesis is a major target for increasing crop yields and ensuring food security. Phenotyping of photosynthesis in the field is critical to understand the limits to crop performance in agricultural settings. Yet, detailed phenotyping of photosynthetic traits is relatively scarce in field-grown wheat, with previous studies focusing on narrow germplasm selections. Flag leaf photosynthetic traits, crop development, and yield traits were compared in 64 field-grown wheat cultivars in the UK. Pre-anthesis and post-anthesis photosynthetic traits correlated significantly and positively with grain yield and harvest index (HI). These traits included net CO2 assimilation measured at ambient CO2 concentrations and a range of photosynthetic photon flux densities, and traits associated with the light response of photosynthesis. In most cultivars, photosynthesis decreased post-anthesis compared with pre-anthesis, and this was associated with decreased Rubisco activity and abundance. Heritability of photosynthetic traits suggests that phenotypic variation can be used to inform breeding programmes. Specific cultivars were identified with traits relevant to breeding for increased crop yields in the UK: pre-anthesis photosynthesis, post-anthesis photosynthesis, light response of photosynthesis, and Rubisco amounts. The results indicate that flag leaf longevity and operating photosynthetic activity in the canopy can be further exploited to maximize grain filling in UK bread wheat. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Influence of pine straw harvesting, prescribed fire, and fertilization on a Louisiana longleaf pine site

Treesearch

James D. Haywood

2009-01-01

This research was initiated in a 34-year-old, direct-seeded stand of longleaf pine (Pinus palustris Mill.) to study how pine straw management practices (harvesting, fire, and fertilization) affected the longleaf pine overstory and pine straw yields. A randomized complete block split-plot design was installed with two main plot treatments...

Estimating national crop yield potential and the relevance of weather data sources

NASA Astrophysics Data System (ADS)

Van Wart, Justin

2011-12-01

To determine where, when, and how to increase yields, researchers often analyze the yield gap (Yg), the difference between actual current farm yields and crop yield potential. Crop yield potential (Yp) is the yield of a crop cultivar grown under specific management limited only by temperature and solar radiation and also by precipitation for water limited yield potential (Yw). Yp and Yw are critical components of Yg estimations, but are very difficult to quantify, especially at larger scales because management data and especially daily weather data are scarce. A protocol was developed to estimate Yp and Yw at national scales using site-specific weather, soils and management data. Protocol procedures and inputs were evaluated to determine how to improve accuracy of Yp, Yw and Yg estimates. The protocol was also used to evaluate raw, site-specific and gridded weather database sources for use in simulations of Yp or Yw. The protocol was applied to estimate crop Yp in US irrigated maize and Chinese irrigated rice and Yw in US rainfed maize and German rainfed wheat. These crops and countries account for >20% of global cereal production. The results have significant implications for past and future studies of Yp, Yw and Yg. Accuracy of national long-term average Yp and Yw estimates was significantly improved if (i) > 7 years of simulations were performed for irrigated and > 15 years for rainfed sites, (ii) > 40% of nationally harvested area was within 100 km of all simulation sites, (iii) observed weather data coupled with satellite derived solar radiation data were used in simulations, and (iv) planting and harvesting dates were specified within +/- 7 days of farmers actual practices. These are much higher standards than have been applied in national estimates of Yp and Yw and this protocol is a substantial step in making such estimates more transparent, robust, and straightforward. Finally, this protocol may be a useful tool for understanding yield trends and directing

Evaluation of yield and quality of photoperiod sensitive sorghum and sorghum sudangrass

USDA-ARS?s Scientific Manuscript database

A 2-year study was conducted at 2 sites (Hancock, Marshfield) in central Wisconsin to assess yield and quality of photoperiod sensitive (PS) and non-PS sorghums in relation to corn planted on 2 dates and harvested once or twice. At each site, treatments were arranged as a split-split plot in a rando...

Following the fate of harvest-damaged trees 13 years after harvests

Treesearch

Randy G. Jensen; John M. Kabrick

2014-01-01

Logging damage to residual trees during harvest operations can reduce the future volume, quality, and value of wood products. Timber harvests in 1996 on the Missouri Ozark Forest Ecosystem Project (MOFEP) provided a rare opportunity to follow the fate of trees wounded by felling or by skidding with rubber-tired skidders.

Variability of arginine content and yield components in Valencia peanut germplasm.

PubMed

Aninbon, Chorkaew; Jogloy, Sanun; Vorasoot, Nimitr; Nuchadomrong, Suporn; Holbrook, C Corley; Kvien, Craig; Puppala, Naveen; Patanothai, Aran

2017-06-01

Peanut seeds are rich in arginine, an amino acid that has several positive effects on human health. Establishing the genetic variability of arginine content in peanut will be useful for breeding programs that have high arginine as one of their goals. The objective of this study was to evaluate the variation of arginine content, pods/plant, seeds/pod, seed weight, and yield in Valencia peanut germplasm. One hundred and thirty peanut genotypes were grown under field condition for two years. A randomized complete block design with three replications was used for this study. Arginine content was analyzed in peanut seeds at harvest using spectrophotometry. Yield and yield components were recorded for each genotype. Significant differences in arginine content and yield components were found in the tested Valencia peanut germplasm. Arginine content ranged from 8.68-23.35 μg/g seed. Kremena was the best overall genotype of high arginine content, number of pods/plant, 100 seed weight and pod yield.

Overexpression of OsGATA12 regulates chlorophyll content, delays plant senescence and improves rice yield under high density planting.

PubMed

Lu, Guangwen; Casaretto, José A; Ying, Shan; Mahmood, Kashif; Liu, Fang; Bi, Yong-Mei; Rothstein, Steven J

2017-05-01

Agronomic traits controlling the formation, architecture and physiology of source and sink organs are main determinants of rice productivity. Semi-dwarf rice varieties with low tiller formation but high seed production per panicle and dark green and thick leaves with prolonged source activity are among the desirable traits to further increase the yield potential of rice. Here, we report the functional characterization of a zinc finger transcription factor, OsGATA12, whose overexpression causes increased leaf greenness, reduction of leaf and tiller number, and affects yield parameters. Reduced tillering allowed testing the transgenic plants under high density which resulted in significantly increased yield per area and higher harvest index compared to wild-type. We show that delayed senescence of transgenic plants and the corresponding longer stay-green phenotype is mainly due to increased chlorophyll and chloroplast number. Further, our work postulates that the increased greenness observed in the transgenic plants is due to more chlorophyll synthesis but most significantly to decreased chlorophyll degradation, which is supported by the reduced expression of genes involved in the chlorophyll degradation pathway. In particular we show evidence for the down-regulation of the STAY GREEN RICE gene and in vivo repression of its promoter by OsGATA12, which suggests a transcriptional repression function for a GATA transcription factor for prolonging the onset of senescence in cereals.

Effects of changing climate and cultivar on the phenology and yield of winter wheat in the North China Plain

NASA Astrophysics Data System (ADS)

Li, Kenan; Yang, Xiaoguang; Tian, Hanqin; Pan, Shufen; Liu, Zhijuan; Lu, Shuo

2016-01-01

Understanding how changing climate and cultivars influence crop phenology and potential yield is essential for crop adaptation to future climate change. In this study, crop and daily weather data collected from six sites across the North China Plain were used to drive a crop model to analyze the impacts of climate change and cultivar development on the phenology and production of winter wheat from 1981 to 2005. Results showed that both the growth period (GP) and the vegetative growth period (VGP) decreased during the study period, whereas changes in the reproductive growth period (RGP) either increased slightly or had no significant trend. Although new cultivars could prolong the winter wheat phenology (0.3˜3.8 days per decade for GP), climate warming impacts were more significant and mainly accounted for the changes. The harvest index and kernel number per stem weight have significantly increased. Model simulation indicated that the yield of winter wheat exhibited increases (5.0˜19.4 %) if new cultivars were applied. Climate change demonstrated a negative effect on winter wheat yield as suggested by the simulation driven by climate data only (-3.3 to -54.8 kg ha-1 year-1, except for Lushi). Results of this study also indicated that winter wheat cultivar development can compensate for the negative effects of future climatic change.

Effects of changing climate and cultivar on the phenology and yield of winter wheat in the North China Plain.

PubMed

Li, Kenan; Yang, Xiaoguang; Tian, Hanqin; Pan, Shufen; Liu, Zhijuan; Lu, Shuo

2016-01-01

Understanding how changing climate and cultivars influence crop phenology and potential yield is essential for crop adaptation to future climate change. In this study, crop and daily weather data collected from six sites across the North China Plain were used to drive a crop model to analyze the impacts of climate change and cultivar development on the phenology and production of winter wheat from 1981 to 2005. Results showed that both the growth period (GP) and the vegetative growth period (VGP) decreased during the study period, whereas changes in the reproductive growth period (RGP) either increased slightly or had no significant trend. Although new cultivars could prolong the winter wheat phenology (0.3∼3.8 days per decade for GP), climate warming impacts were more significant and mainly accounted for the changes. The harvest index and kernel number per stem weight have significantly increased. Model simulation indicated that the yield of winter wheat exhibited increases (5.0∼19.4%) if new cultivars were applied. Climate change demonstrated a negative effect on winter wheat yield as suggested by the simulation driven by climate data only (-3.3 to -54.8 kg ha(-1) year(-1), except for Lushi). Results of this study also indicated that winter wheat cultivar development can compensate for the negative effects of future climatic change.

The reamer-irrigator-aspirator as a device for harvesting bone graft compared with iliac crest bone graft: union rates and complications.

PubMed

Dawson, John; Kiner, Dirk; Gardner, Warren; Swafford, Rachel; Nowotarski, Peter J

2014-10-01

This study was performed to compare patient outcomes after Reamer-Irrigator-Aspirator (RIA)-harvested bone grafting with the current gold standard, either anterior or posterior iliac crest bone graft (ICBG). Prospective randomized controlled trial. Multicenter study at 3 geographically separate Level 1 trauma centers. One hundred thirty-three patients with nonunion or posttraumatic segmental bone defect requiring operative intervention. Patients were prospectively randomized to receive ICBG or RIA autograft. Supplemental internal fixation was performed per surgeon preference. Operative data included amount of graft, time of harvest, and associated surgical costs. The Short Musculoskeletal Functional Assessment and the Visual Analog Scale were used to document baseline and postoperative function and pain. Clinical and radiographic union was the defined end point; patients considered to have failed treatment if they either developed an infection requiring operative treatment or had a persistent nonunion of the grafted extremity. One hundred thirteen of the 133 enrolled patients were followed until union and included in the final analysis. Intraoperative data showed anterior ICBG to yield 20.7 ± 12.8 (5-60) cm of autograft with an average harvest time of 33.2 ± 16.2 minutes, posterior ICBG yielded 36.1 ± 21.3 (20-100) cm of autograft in 40.6 ± 11.2 minutes, and RIA yielded 37.7 ± 12.9 (5-90) cm in 29.4 ± 15.1 minutes. Anterior ICBG produced significantly less bone graft than either RIA or posterior ICBG (P < 0.001). The RIA harvest was completed in significantly less operative time compared with posterior ICBG (P = 0.005). At $738, the RIA setup was considerably more expensive than the ∼$100 cost of a bone graft tray; however, when compared with posterior ICBG, the longer operative time required for a posterior harvest came at an additional incremental cost of $990-1880, making RIA the less expensive option. Patients were followed for an average of 56.9 ± 42

A method for mass harvesting islets (Brockmann bodies) from teleost fish.

PubMed

Yang, H; Wright, J R

1995-01-01

In certain species of fish, the insulin-producing tissue is uniquely located in separate structures called Brockmann bodies (BBs). Tilapia BBs have been shown to be a simple and inexpensive source of islet cells for xenotransplantation research. Each donor tilapia contains roughly 12-15 BBs, measuring from 0.3 to 5.0 mm in maximum dimension, in a triangular region of adipose tissue bounded by the liver, stomach, and spleen/gallbladder. At present, the larger BBs (usually 2-4) are harvested by microdissecting these "BB regions" using jeweler's forceps and microvascular scissors while being visualized with the aid of a dissecting microscope. It is a simple but time-consuming task that would not be applicable for harvesting massive amounts of BB tissue for large animal studies. Therefore, we have developed an easier and more efficient method of harvesting BBs based on a standard enzymatic method for isolating human adipocytes. BB regions are harvested from donor fish and pooled into a 50 mL plastic tube containing collagenase Type II (3 mg/mL) in Hank's balanced salt solution (HBSS); the tube is then placed in a 37 degrees C waterbath/shaker for roughly 15 min. The exact length of the digestion interval is determined by visual inspection of the tube to determine whether the BBs have been liberated. The digestion is then stopped by adding excess cold HBSS. The adipocytes float while the BBs and residual connective tissue (i.e., a few blood vessels, nerves, and bile ducts) form a pellet. The pellet is washed several times in HBSS and then placed in a culture dish. The BBs are easily handpicked with a siliconized pipette. Based on functional data and DNA content, this new method roughly doubles or triples our yield of BB tissue per donor fish. To determine whether BBs harvested in this manner functioned in a manner similar to those harvested by microdissection, we performed a series of transplants using mass-harvested BBs. Long-term normoglycemia was achieved in

Arthroscopic Harvest of Adipose-Derived Mesenchymal Stem Cells From the Infrapatellar Fat Pad.

PubMed

Dragoo, Jason L; Chang, Wenteh

2017-11-01

The successful isolation of adipose-derived mesenchymal stem cells (ADSCs) from the arthroscopically harvested infrapatellar fat pad (IFP) would provide orthopaedic surgeons with an autologous solution for regenerative procedures. To demonstrate the quantity and viability of the mesenchymal stem cell population arthroscopically harvested from the IFP as well as the surrounding synovium. Descriptive laboratory study. The posterior border of the IFP, including the surrounding synovial tissue, was harvested arthroscopically from patients undergoing anterior cruciate ligament reconstruction. Tissue was then collected in an AquaVage adipose canister, followed by fat fractionization using syringe emulsification and concentration with an AdiPrep device. In the laboratory, the layers of tissue were separated and then digested with 0.3% type I collagenase. The pelleted stromal vascular fraction (SVF) cells were then immediately analyzed for viability, mesenchymal cell surface markers by fluorescence-activated cell sorting, and clonogenic capacity. After culture expansion, the metabolic activity of the ADSCs was assessed by an AlamarBlue assay, and the multilineage differentiation capability was tested. The transition of surface antigens from the SVF toward expanded ADSCs at passage 2 was further evaluated. SVF cells were successfully harvested with a mean yield of 4.86 ± 2.64 × 10 5 cells/g of tissue and a mean viability of 69.03% ± 10.75%, with ages ranging from 17 to 52 years (mean, 35.14 ± 13.70 years; n = 7). The cultured ADSCs composed a mean 5.85% ± 5.89% of SVF cells with a mean yield of 0.33 ± 0.42 × 10 5 cells/g of tissue. The nonhematopoietic cells (CD45 - ) displayed the following surface antigens as a percentage of the viable population: CD44 + (52.21% ± 4.50%), CD73 + CD90 + CD105 + (19.20% ± 17.04%), and CD44 + CD73 + CD90 + CD105 + (15.32% ± 15.23%). There was also a significant increase in the expression of ADSC markers CD73 (96.97% ± 1.72%; P

A Computer Program for Variable Density Yield Tables for Loblolly Pine Plantations

Treesearch

Clifford A. Myers

1977-01-01

The computer program described here uses relationships developed from research on loblolly pine growth to predict volumes and yields of planted stands, over the site range of the species, under a wide range of management alternatives. Timing and severity of thinnings, length of rotation, and type of harvest can be modified to compare the effects of various management...

Establishment and yield of perennial grass monocultures and binary mixtures for bioenergy in North Dakota

USDA-ARS?s Scientific Manuscript database

To develop appropriate bioenergy production systems to match site-specific situations, establishment and yield were evaluated for switchgrass, intermediate wheatgrass, tall wheatgrass, and three binary mixtures at four sites in North Dakota from 2006 to 2011. Canopy cover at harvest for intermediat...

[Effects of increased planting density with reduced nitrogen fertilizer application on rice yield, N use efficiency and greenhouse gas emission in Northeast China].

PubMed

Zhu, Xiang-cheng; Zhang, Zhen-ping; Zhang, Jun; Deng, Ai-xing; Zhang, Wei-jian

2016-02-01

The traditional rice growing practice has to change to save resource and protect environment, and it' s necessary to develop new technology in rice cultivation. Therefore, a two-year field experiment of Japonica rice (Liaoxing 1) was conducted in Northeast China in 2012 and 2013 to investigate the integrated effects of dense planting with less basal nitrogen (N) and unchanged top-dressing N (IR) on rice yield, N use efficiency (NUE) and greenhouse gas emissions. Compared with traditional practice (CK), we increased the rice seedling density by 33.3% and reduced the basal N rate by 20%. The results showed that the average N agronomy efficiency and partial factor productivity were improved by 49.6% (P<0.05) and 20.4% (P<0.05), respectively, while the area and yield-scaled greenhouse gas emissions were reduced by 9.9% and 12.7% (P<0.05), respectively. Although IR cropping mode decreased panicle number and biomass production, it significantly enhanced rice seed setting rate and harvest index, resulting in an unchanged or even highei yield. NH4+-N and NO3(-)-N concentrations in rice rhizosphere soil were reduced, resulting in an increment of N recovery efficiency. Generally, proper dense planting with less basal N applicatior could be a good approach for the trade-off between rice yield, NUE and greenhouse gas emission.

Double synchronized switch harvesting (DSSH): a new energy harvesting scheme for efficient energy extraction.

PubMed

Lallart, Mickaël; Garbuio, Lauric; Petit, Lionel; Richard, Claude; Guyomar, Daniel

2008-10-01

This paper presents a new technique for optimized energy harvesting using piezoelectric microgenerators called double synchronized switch harvesting (DSSH). This technique consists of a nonlinear treatment of the output voltage of the piezoelectric element. It also integrates an intermediate switching stage that ensures an optimal harvested power whatever the load connected to the microgenerator. Theoretical developments are presented considering either constant vibration magnitude, constant driving force, or independent extraction. Then experimental measurements are carried out to validate the theoretical predictions. This technique exhibits a constant output power for a wide range of load connected to the microgenerator. In addition, the extracted power obtained using such a technique allows a gain up to 500% in terms of maximal power output compared with the standard energy harvesting method. It is also shown that such a technique allows a fine-tuning of the trade-off between vibration damping and energy harvesting.

Influence of yield on in vitro accumulation of aflatoxins in pecan (Carya illinoensis (Wang.) K. Koch) nutmeats.

PubMed Central

McMeans, J L

1983-01-01

Pecans were harvested from trees (Carya illinoensis (Wang.) K. Koch) in November of 1977 through 1979. Kernel meals from high-, medium-, and low-yielding trees were inoculated with a spore suspension of Aspergillus parasiticus and incubated for 7 days at 25 degrees C. Significant differences in aflatoxin accumulation were found among the three substrates, with a direct correlation between high aflatoxin concentration and tree yield. PMID:6830223

Influence of yield on in vitro accumulation of aflatoxins in pecan (Carya illinoensis (Wang.) K. Koch) nutmeats.

PubMed

McMeans, J L

1983-02-01

Pecans were harvested from trees (Carya illinoensis (Wang.) K. Koch) in November of 1977 through 1979. Kernel meals from high-, medium-, and low-yielding trees were inoculated with a spore suspension of Aspergillus parasiticus and incubated for 7 days at 25 degrees C. Significant differences in aflatoxin accumulation were found among the three substrates, with a direct correlation between high aflatoxin concentration and tree yield.

Effects of harvesting flowers from shrubs on the persistence and abundance of wild shrub populations at multiple spatial extents.

PubMed

Cabral, Juliano Sarmento; Bond, William J; Midgley, Guy F; Rebelo, Anthony G; Thuiller, Wilfried; Schurr, Frank M

2011-02-01

Wildflower harvesting is an economically important activity of which the ecological effects are poorly understood. We assessed how harvesting of flowers affects shrub persistence and abundance at multiple spatial extents. To this end, we built a process-based model to examine the mean persistence and abundance of wild shrubs whose flowers are subject to harvest (serotinous Proteaceae in the South African Cape Floristic Region). First, we conducted a general sensitivity analysis of how harvesting affects persistence and abundance at nested spatial extents. For most spatial extents and combinations of demographic parameters, persistence and abundance of flowering shrubs decreased abruptly once harvesting rate exceeded a certain threshold. At larger extents, metapopulations supported higher harvesting rates before their persistence and abundance decreased, but persistence and abundance also decreased more abruptly due to harvesting than at smaller extents. This threshold rate of harvest varied with species' dispersal ability, maximum reproductive rate, adult mortality, probability of extirpation or local extinction, strength of Allee effects, and carrying capacity. Moreover, spatial extent interacted with Allee effects and probability of extirpation because both these demographic properties affected the response of local populations to harvesting more strongly than they affected the response of metapopulations. Subsequently, we simulated the effects of harvesting on three Cape Floristic Region Proteaceae species and found that these species reacted differently to harvesting, but their persistence and abundance decreased at low rates of harvest. Our estimates of harvesting rates at maximum sustainable yield differed from those of previous investigations, perhaps because researchers used different estimates of demographic parameters, models of population dynamics, and spatial extent than we did. Good demographic knowledge and careful identification of the spatial extent

Modelling crop yield in Iberia under drought conditions

NASA Astrophysics Data System (ADS)

Ribeiro, Andreia; Páscoa, Patrícia; Russo, Ana; Gouveia, Célia

2017-04-01

The improved assessment of the cereal yield and crop loss under drought conditions are essential to meet the increasing economy demands. The growing frequency and severity of the extreme drought conditions in the Iberian Peninsula (IP) has been likely responsible for negative impacts on agriculture, namely on crop yield losses. Therefore, a continuous monitoring of vegetation activity and a reliable estimation of drought impacts is crucial to contribute for the agricultural drought management and development of suitable information tools. This works aims to assess the influence of drought conditions in agricultural yields over the IP, considering cereal yields from mainly rainfed agriculture for the provinces with higher productivity. The main target is to develop a strategy to model drought risk on agriculture for wheat yield at a province level. In order to achieve this goal a combined assessment was made using a drought indicator (Standardized Precipitation Evapotranspiration Index, SPEI) to evaluate drought conditions together with a widely used vegetation index (Normalized Difference Vegetation Index, NDVI) to monitor vegetation activity. A correlation analysis between detrended wheat yield and SPEI was performed in order to assess the vegetation response to each time scale of drought occurrence and also identify the moment of the vegetative cycle when the crop yields are more vulnerable to drought conditions. The time scales and months of SPEI, together with the months of NDVI, better related with wheat yield were chosen to perform a multivariate regression analysis to simulate crop yield. Model results are satisfactory and highlighted the usefulness of such analysis in the framework of developing a drought risk model for crop yields. In terms of an operational point of view, the results aim to contribute to an improved understanding of crop yield management under dry conditions, particularly adding substantial information on the advantages of combining

Magnetoelectric Energy Harvesting

DTIC Science & Technology

2014-11-20

materials to rotating or moving machinery , make it difficult to locate piezoelectric material devices in contact with the mechanical stress generator which...mechanical energy harvesting device and more particularly relates to such a device that has a magnetostrictive and piezoelectric component. (2...makes them a candidate as the active material in energy harvesting devices. By utilizing the direct piezoelectric (or pyroelectric) effect when

Harvesting to get a Eucalyptus coppice crop

Treesearch

Thomas F. Geary

1983-01-01

Coppicing of eucalypts saves replanting after harvesting, but plan for coppice before planting seedlings. Select a species that coppices in the planned season of harvest; plan spacing and harvesting methods so that harvesting will not damage stumps; plan coppice management. Best coppice is produced by spring harvest with chain saws, low stumps, no bark or root damage,...

Enhancing enterovirus A71 vaccine production yield by microcarrier profusion bioreactor culture.

PubMed

Liu, Chia-Chyi; Wu, Suh-Chin; Wu, Shang-Rung; Lin, Hsiao-Yu; Guo, Meng-Shin; Yung-Chih Hu, Alan; Chow, Yen-Hung; Chiang, Jen-Ron; Shieh, Dar-Bin; Chong, Pele

2018-05-24

Hand, foot and mouth diseases (HFMD) are mainly caused by Enterovirus A71 (EV-A71) infections. Clinical trials in Asia conducted with formalin-inactivated EV-A71 vaccine candidates produced from serum-free Vero cell culture using either roller bottle or cell factory technology, are found to be safe and highly efficacious. To increase vaccine yields and reduce the production costs, the bioprocess improvement for EV-A71 vaccine manufacturing is currently being investigated. The parameters that could affect and enhance the production yields of EV-A71 virus growth in the microcarrier bioreactor were investigated. The medium replacement culture strategy included a multi-harvested semi-batch process and perfusion technology and was found to increase the production yields more than 7-14 folds. Based on the western blot and cryo-EM analyses of the EV-A71 virus particles produced from either the multi-harvested semi-batch (MHSBC) or perfusion cultures were found to be similar to those virus particles obtained from the single batch culture. Mouse immunogenicity studies indicate that the EV-A71 vaccine candidates produced from the perfusion culture have similar potency to those obtained from single batch bioprocess. The physical structures of the EV-A71 particles revealed by the cryo-EM analysis were found to be spherical capsid particles. These results provide feasible technical bioprocesses for increasing virus yields and the scale up of EV-A71 vaccine manufacturing using the bioreactor cell culture methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

An experimental case study to estimate Pre-harvest Wheat Acreage/Production in Hilly and Plain region of Uttarakhand state: Challenges and solutions of problems by using satellite data

NASA Astrophysics Data System (ADS)

Uniyal, D.; Kimothi, M. M.; Bhagya, N.; Ram, R. D.; Patel, N. K.; Dhaundiya, V. K.

2014-11-01

Wheat is an economically important Rabi crop for the state, which is grown on around 26 % of total available agriculture area in the state. There is a variation in productivity of wheat crop in hilly and tarai region. The agricultural productivity is less in hilly region in comparison of tarai region due to terrace cultivation, traditional system of agriculture, small land holdings, variation in physiography, top soil erosion, lack of proper irrigation system etc. Pre-harvest acreage/yield/production estimation of major crops is being done with the help of conventional crop cutting method, which is biased, inaccurate and time consuming. Remote Sensing data with multi-temporal and multi-spectral capabilities has shown new dimension in crop discrimination analysis and acreage/yield/production estimation in recent years. In view of this, Uttarakhand Space Applications Centre (USAC), Dehradun with the collaboration of Space Applications Centre (SAC), ISRO, Ahmedabad and Uttarakhand State Agriculture Department, have developed different techniques for the discrimination of crops and estimation of pre-harvest wheat acreage/yield/production. In the 1st phase, five districts (Dehradun, Almora, Udham Singh Nagar, Pauri Garhwal and Haridwar) with distinct physiography i.e. hilly and plain regions, have been selected for testing and verification of techniques using IRS (Indian Remote Sensing Satellites), LISS-III, LISS-IV satellite data of Rabi season for the year 2008-09 and whole 13 districts of the Uttarakhand state from 2009-14 along with ground data were used for detailed analysis. Five methods have been developed i.e. NDVI (Normalized Differential Vegetation Index), Supervised classification, Spatial modeling, Masking out method and Programming on visual basics methods using multitemporal satellite data of Rabi season along with the collateral and ground data. These methods were used for wheat discriminations and preharvest acreage estimations and subsequently results

Photoperiod shift effects on yield characteristics of rice

NASA Technical Reports Server (NTRS)

Volk, G. M.; Mitchell, C. A.

1995-01-01

Edible yield must be maximized for each crop species selected for inclusion in the Controlled Ecological Life-Support System (CELSS) proposed by NASA to support long-term manned space missions. In a greenhouse study aimed at increasing biomass partitioning to rice (Oryza sativa L.) grain, plants of the high yielding semi-dwarf rice cultivar Ai-Nan-Tsao were started in pots under 8-h photoperiods at a density of 212 plants m-2. After different periods of time under 8-h photoperiods, pots were switched to continuous light for the remainder of the cropping cycle. Continuous light did not delay time to first panicle emergence (60 d) or time to harvest (83 d). There was a positive correlation between the length of continuous light treatments and nongrain biomass. Grain yield (1.6 +/- 0.2 g plant-1) did not increase in continuous light. Yield-efficiency rate (grain weight per length of cropping cycle, canopy volume, and weight of nongrain shoot biomass) was used to compare treatments. Small Ai-Nan-Tsao rice canopies grown under 8-h photoperiods were more efficient producers of grain than canopies grown under continuous light for a portion of the rice cropping cycle.

A new economic assessment index for the impact of climate change on grain yield

NASA Astrophysics Data System (ADS)

Dong, Wenjie; Chou, Jieming; Feng, Guolin

2007-03-01

The impact of climate change on agriculture has received wide attention by the scientific community. This paper studies how to assess the grain yield impact of climate change, according to the climate change over a long time period in the future as predicted by a climate system model. The application of the concept of a traditional “yield impact of meteorological factor (YIMF)” or “yield impact of weather factor” to the grain yield assessment of a decadal or even a longer timescale would be suffocated at the outset because the YIMF is for studying the phenomenon on an interannual timescale, and it is difficult to distinguish between the trend caused by climate change and the one resulting from changes in non-climatic factors. Therefore, the concept of the yield impact of climatic change (YICC), which is defined as the difference in the per unit area yields (PUAY) of a grain crop under a changing and an envisaged invariant climate conditions, is presented in this paper to assess the impact of global climate change on grain yields. The climatic factor has been introduced into the renowned economic Cobb-Douglas model, yielding a quantitative assessment method of YICC using real data. The method has been tested using the historical data of Northeast China, and the results show that it has an encouraging application outlook.

New Insight into the Angle Insensitivity of Ultrathin Planar Optical Absorbers for Broadband Solar Energy Harvesting.

PubMed

Liu, Dong; Yu, Haitong; Duan, Yuanyuan; Li, Qiang; Xuan, Yimin

2016-09-01

Two challenging problems still remain for optical absorbers consisting of an ultrathin planar semiconductor film on top of an opaque metallic substrate. One is the angle-insensitive mechanism and the other is the system design needed for broadband solar energy harvesting. Here, first we theoretically demonstrates that the high refractive index, instead of the ultrathin feature as reported in previous studies, is the physical origin of the angle insensitivity for ultrathin planar optical absorbers. They exhibit omnidirectional resonance for TE polarization due to the high complex refractive index difference between the semiconductor and the air, while for TM polarization the angle insensitivity persists up to an incident angle related to the semiconductor refractive index. These findings were validated by fabricating and characterizing an 18 nm Ge/Ag absorber sample (representative of small band gap semiconductors for photovoltaic applications) and a 22 nm hematite/Ag sample (representative of large band gap semiconductors for photoelectrochemical applications). Then, we took advantage of angle insensitivity and designed a spectrum splitting configuration for broadband solar energy harvesting. The cascaded solar cell and unassisted solar water splitting systems have photovoltaic and photoelectrochemical cells that are also spectrum splitters, so an external spectrum splitting element is not needed.

Nerve stripper-assisted sural nerve harvest.

PubMed

Hassanpour, Esmail; Yavari, Masoud; Karbalaeikhani, Ali; Saremi, Hossein

2014-03-01

Sural nerve has the favorite length and size for nerve graft interposition. Here two techniques, that is, "stocking seam" and "stair-step" or "stepladder," have been used for harvesting sural nerve. The first technique results in an unsightly scar at the posterior calf, and the latter one takes a long time to perform and exert undue traction to the graft during harvesting. The purpose of this article is to describe our experience in harvesting the sural nerve by a nerve stripper. A nerve stripper was used for harvesting sural nerve in 35 adult patients (in 6 patients, sural harvesting was done bilaterally), 27 men and 8 women. Thirty-one sural nerve harvests were done by closed technique (i.e., harvesting of sural nerve only by two incisions, one in the posterior of the lateral malleolus and the other in popliteal fossa), in 8 others by limited open technique, and in 2 cases, there was early laceration of the sural nerve at the beginning of the study. The contralateral sural nerve was harvested in one patient and medial antebrachial nerve in another by open technique. The mean length of the retrieved sural nerve was 34.5 cm in the closed technique group and 35 cm in the limited open technique group. We detected advancing Tinel's sign in all nerve stripper-assisted sural nerve harvested group members in both the closed and limited open groups. Sural nerve harvesting by the nerve stripper is a reliable and simple technique, and it is applicable as a routine technique. Applying controlled rotatory movements of the nerve stripper instead of pushing can result in satisfactory harvesting of the sural nerve without early laceration. Georg Thieme Verlag KG Stuttgart · New York.

The effects of shelterwood harvesting on oak regeneration two years after harvest in southern Ohio

Treesearch

James D. Downs; Roger A. Williams; Joni A. Downs

2011-01-01

This research examines the effects of two intensities of shelterwood harvesting (reduction of stocking levels to 50 and 70 percent of full stocking) on oak regeneration in southeastern Ohio 2 years after harvest. The main goal of this study is to develop an understanding of the relationship between residual stocking (harvesting intensity) and the successful release of...

Effect of salinity stress on phenotypic plasticity, yield stability, and signature of stable isotopes of carbon and nitrogen in safflower.

PubMed

Hussain, Muhammad Iftikhar; Al-Dakheel, Abdullah J

2018-06-05

Salinity is one of the major factors contributing in land degradation, disturbance of soil biology, a structure that leads to unproductive land with low crop yield potential especially in arid and semiarid regions of the world. Appropriate crops with sufficient stress tolerance capacity and non-conventional water resources should have to be managed in a sustainable way to bring these marginal lands under cultivation for future food security. The goal of the present study was to evaluate salinity tolerant potential (0, 7, and 14 dS m -1 ) of six safflower genotypes that can be adapted to the hyper arid climate of UAE and its marginal soil. Several agro-morphological and physiological traits such as plant dry biomass (PDM), number of branches (BN), number of capitula (CN), seed yield (SY), stable isotope composition of nitrogen (δ 15 N) and carbon (δ 13 C), intercellular CO 2 concentration from inside to ambient air (Ci/Ca), intrinsic water use efficiency (iWUE), carbon (C%) and nitrogen (N %), and harvest index (HI) were evaluated as indicative of the functional performance of safflower genotypes under salt stress. Results indicated that salinity significantly affected the seed yield at all levels and varied significantly among genotypes. The BN, PDM, CN, and δ 13 C attributes showed clear differentiation between tolerant and susceptible genotypes. The δ 13 C results indicate that the tolerant genotypes suffer less from stress, may be due to better rooting. Tolerant genotypes showed lower iWUE values but possess higher yield. Safflower genotypes (PI248836 and PI167390) proved to be salt tolerant, stable, and higher seed and biomass yielder. There was no G × E interaction but the genotypes that produce higher yield under control were still best even under salt stress conditions. Although salinity reduced crop yield, some tolerant genotypes demonstrate adaptation and good yield potential under saline marginal environment.

Adaptability and stability of soybean cultivars for grain yield and seed quality.

PubMed

Silva, K B; Bruzi, A T; Zambiazzi, E V; Soares, I O; Pereira, J L A R; Carvalho, M L M

2017-05-10

This study aimed at verifying the adaptability and stability of soybean cultivars, considering the grain yield and quality of seeds, adopting univariate and multivariate approaches. The experiments were conducted in two crops, three environments, in 2013/2014 and 2014/2015 crop seasons, in the county of Inconfidentes, Lavras, and Patos de Minas, in the Minas Gerais State, Brazil. We evaluated 17 commercial soybean cultivars. For adaptability and stability evaluations, the Graphic and GGE biplot methods were employed. Previously, a selection index was estimated based on the sum of the standardized variables (Z index). The data relative to grain yield, mass of one thousand grain, uniformity test (sieve retention), and germination test were standardized (Z ij ) per cultivar. With the sum of Z ij , we obtained the selection index for the four traits evaluated together. In the Graphic method evaluation, cultivars NA 7200 RR and CD 2737 RR presented the highest values for selection index Z. By the GGE biplot method, we verified that cultivar NA 7200 RR presented greater stability in both univariate evaluations, for grain yield, and for selection index Z.

Evaluation of wheat growth, morphological characteristics, biomass yield and quality in Lunar Palace-1, plant factory, green house and field systems

NASA Astrophysics Data System (ADS)

Dong, Chen; Shao, Lingzhi; Fu, Yuming; Wang, Minjuan; Xie, Beizhen; Yu, Juan; Liu, Hong

2015-06-01

Wheat (Triticum aestivum L.) is one of the most important agricultural crops in both space such as Bioregenerative Life Support Systems (BLSS) and urban agriculture fields, and its cultivation is affected by several environmental factors. The objective of this study was to investigate the influences of different environmental conditions (BLSS, plant factory, green house and field) on the wheat growth, thousand kernel weight (TKW), harvest index (HI), biomass yield and quality during their life cycle. The results showed that plant height partially influenced by the interaction effects with environment, and this influence decreased gradually with the plant development. It was found that there was no significant difference between the BLSS and plant factory treatments on yields per square, but the yield of green house and field treatments were both lower. TKW and HI in BLSS and plant factory were larger than those in the green house and field. However, grain protein concentration can be inversely correlated with grain yield. Grain protein concentrations decreased under elevate CO2 condition and the magnitude of the reductions depended on the prevailing environmental condition. Conditional interaction effects with environment also influenced the components of straw during the mature stage. It indicated that CO2 enriched environment to some extent was better for inedible biomass degradation and had a significant effect on "source-sink flow" at grain filling stage, which was more beneficial to recycle substances in the processes of the environment regeneration.

Effect of plant density and mixing ratio on crop yield in sweet corn/mungbean intercropping.

PubMed

Sarlak, S; Aghaalikhani, M; Zand, B

2008-09-01

In order to evaluate the ear and forage yield of sweet corn (Zea mays L. var. Saccarata) in pure stand and intercropped with mung bean (Vigna radiata L.), a field experiment was conducted at Varamin region on summer 2006. Experiment was carried out in a split plot design based on randomized complete blocks with 4 replications. Plant density with 3 levels [Low (D1), Mean (D2) and High (D3) respecting 6, 8 and 10 m(-2) for sweet corn, cultivar S.C.403 and 10, 20 and 30 m(-2) for mung bean cultivar, Partow] was arranged in main plots and 5 mixing ratios [(P1) = 0/100, (P2) = 25/75, (P3) = 50/50, (P4) = 75/25, (P5) = 100/0% for sweet corn/mung bean, respectively] were arranged in subplots. Quantitative attributes such as plant height, sucker numbers, LER, dry matter distribution in different plant organs were measured in sweet corn economical maturity. Furthermore the yield of cannable ear corn and yield components of sweet corn and mung bean were investigated. Results showed that plant density has not any significant effect on evaluated traits, while the effect of mixing ratio was significant (p < 0.01). Therefore, the mixing ratio of 75/25 (sweet corn/mung bean) could be introduced as the superior mixing ratio; because of it's maximum rate of total sweet corn's biomass, forage yield, yield and yield components of ear corn in intercropping. Regarding to profitability indices of intercropping, the mixing ratio 75/25 (sweet corn/mung bean) in low density (D1P2) which showed the LER = 1.03 and 1.09 for total crop yield before ear harvesting and total forage yield after ear harvest respectively, was better than corn or mung bean monoculture.

Simulating adaptive wood harvest in a changing climate

NASA Astrophysics Data System (ADS)

Yousefpour, Rasoul; Nabel, Julia; Pongratz, Julia

2016-04-01

"sustained yields" (SY), i.e. that wood harvest is not allowed to reduce wood carbon stocks below their present-day average state. We find that the potentials for SY range from about 420 to 610 PgC cumulatively until 2100 depending on assumed future climate (RCPs 2.6, 4.5 or 8.5). They are thus substantially higher than the harvest prescribed in the context of the same RCPs for the coupled model intercomparison project (CMIP5), which ranged from about 130 to 210 PgC. The underlying drivers of the higher potentials of SY as compared to the RCP harvest are in all scenarios foremost avoided natural mortality, followed by avoided losses due to fire and windbreak. Further, usage of the increase in forest carbon stocks simulated with time under RCP harvest plays a large role in the first decades of the 21st century. The potential wood harvest that we simulate accounting for environmental changes does not include considerations on biodiversity and other ecosystem services or technical feasibility. However, the substantially higher simulated harvest from SY as compared to that prescribed from the RCPs and the difference found between climate scenarios highlights the need to account for effects of environmental changes on vegetation growth also in socio-economic models and thus the need for a consistent representation of climate-landuse interactions.

Guidelines for rainwater harvesting system design and assessment for the city of Johannesburg, South Africa

NASA Astrophysics Data System (ADS)

Ndiritu, John; Ilemobade, Adesola; Kagoda, Paulo

2018-06-01

As water demand increases rainwater harvesting (RWH) systems are increasingly being installed for water supply but comprehensive hydrologic design guidelines for RWH do not exist in many parts of the world. The objective of this study was to develop guidelines for the hydrologic design and assessment of rainwater harvesting (RWH) systems in the City of Johannesburg, South Africa. The data for developing the guidelines were mainly obtained from multiple daily simulations of potential RWH systems in the city. The simulations used daily rainfall from 8 stations and demands based on the probable non-potable uses of RWH systems - toilet flushing, air conditioning and irrigation. The guidelines were confined to systems that would typically fill up in the wet season and empty towards the end of the dry season of the same year. Therefore, supply-to-demand ratios ranging from 0.1 to 0.9 were applied. Two generalized design charts of dimensionless relationships were developed. One relates the yield ratio with supply-to-demand ratio and reliability while the other relates the yield ratio with the storage-to-demand ratio and reliability. Reliability was defined as the probability of exceedance of annual yield in order to incorporate the large inter-annual variability of rainfall experienced in the region. The analyses and design of an example RWH system is used to illustrate the application of the design charts.

Phosphorus, zinc, and boron influence yield components in Earliglow strawberry

DOE Office of Scientific and Technical Information (OSTI.GOV)

May, G.M.; Pritts, M.P.

1993-01-01

The main effects and interactions of soil-applied P, B, and Zn on yield and its components were examined in the field at two pH levels with Earliglow' strawberries (Fragaria ananassa Duch.). Applied nutrients had significant effects on several yield components, but responses depended on the levels of other nutrients or the soil pH. At a soil pH of 5.5, yield responded linearly to B and quadratically to P. At pH 6.5, P interacted with B and Zn. Fruit count per inflorescence was the yield component most strongly associated with yield, followed by individual fruit weight. However, these two yield componentsmore » responded differently to soil-applied nutrients. Foliar nutrient levels generally did not increase with the amount of applied nutrient, but often an applied nutrient had a strong effect on the level of another nutrient. Leaf nutrient levels were often correlated with fruit levels, but foliar and fruit levels at harvest were not related to reproductive performance. The study identifies some of the problems inherent in using foliar nutrient levels to predict a yield response and demonstrates how plant responses to single nutrients depend on soil chemistry and the presence of other nutrients.« less

Carcass fabrication yields of beef steers supplemented zilpaterol hydrochloride and offered ad libitum or maintenance energy intake.

PubMed

Schmitz, Angela N; Walter, Lee-Anne J; Nichols, Wade T; Hutcheson, John P; Lawrence, Ty E

2018-06-04

An experiment was conducted to evaluate the fabrication yields of carcasses from beef steers supplemented zilpaterol hydrochloride (ZH) and fed at maintenance (MA) or ad libitum (AB) intake levels. Beef steers (n = 56) from a common sire were blocked (n = 28 per block) by terminal growth implant and sorted into pairs by BW. Four pairs (n = 8) were harvested on day 0; the remaining 24 pairs (n = 48) were assigned to a dietary intake level (MA or AB) and days on feed (28 or 56 d). Within pairs of MA or AB intakes, steers harvested on day 56 were randomly assigned to supplementation of ZH (90 mg·d-1 per steer) for 20 d followed by a withdrawal period of 4 d or control (C). Steers (BW = 603.5 ± 48.1 kg) were harvested at a commercial processing facility. After a 24-h chill period, standard USDA grading procedures were used to derive a calculated yield grade and quality grade. Following grading, left carcass sides were transported to the West Texas A&M University Meat Laboratory for fabrication. Each side was fabricated into subprimals to determine individual red meat yield (RMY), trimmable fat yield (TFY), and bone yield (BY). A mixed model was used for analysis; fixed effects included treatment combinations and random effects included block and pairs. Single df contrasts tested day 0 vs. 28, day 0 vs. 56, day 28 vs. 56, MA vs. AB, and C vs. ZH. Yield of chuck eye roll differed (P = 0.05) by days on feed (0 d = 4.14, 28 d = 4.11, 56 d = 4.55%). Similarly, eye of round yield was impacted (P = 0.02) by days on feed (0 d = 1.51, 28 d = 1.37, 56 d = 1.36%). Additionally, brisket yield was altered (P < 0.01) by days on feed (0 d = 4.08, 28 d = 3.56, 56 d = 3.48%) and treatment (C = 3.34, ZH = 3.61%). For remaining subprimals, no differences (P ≥ 0.15) were detected. Furthermore, results indicated that RMY tended (P = 0.07) to differ by treatment (C = 61.35, ZH = 63.67%). Comparatively, TFY was impacted (P = 0.04) by intake (MA = 20.44, AB = 23.33%). Results from this

Review of magnetostrictive vibration energy harvesters

NASA Astrophysics Data System (ADS)

Deng, Zhangxian; Dapino, Marcelo J.

2017-10-01

The field of energy harvesting has grown concurrently with the rapid development of portable and wireless electronics in which reliable and long-lasting power sources are required. Electrochemical batteries have a limited lifespan and require periodic recharging. In contrast, vibration energy harvesters can supply uninterrupted power by scavenging useful electrical energy from ambient structural vibrations. This article reviews the current state of vibration energy harvesters based on magnetostrictive materials, especially Terfenol-D and Galfenol. Existing magnetostrictive harvester designs are compared in terms of various performance metrics. Advanced techniques that can reduce device size and improve performance are presented. Models for magnetostrictive devices are summarized to guide future harvester designs.

Harvesting systems and costs for short rotation poplar

Treesearch

B. Rummer; D. Mitchell

2013-01-01

The objective of this review is to compare the cost of coppice and longer rotation poplar harvesting technology. Harvesting technology for short rotation poplar has evolved over the years to address both coppice harvest and single-stem harvest systems. Two potential approaches for coppice harvesting are modified forage harvesters and modified mulcher-balers. Both of...

Tuber yield and quality characteristics of potatoes for off-season crops in a Mediterranean environment.

PubMed

Ierna, Anita

2010-01-15

There is little research on evaluating the compatibility of potatoes for double cropping in southern Italy. The aim of this investigation was to assess tuber yield and some qualitative traits of tubers such as skin colour, tuber dry matter content and tuber nitrate content, both in winter-spring and in summer-autumn crops, as influenced by genotype and harvest time. Yield, skin colour and dry matter content of tubers were higher in the winter-spring crop than in the summer-autumn crop, attributable to the advantageous lag time in spring between solar radiation and temperatures and the disadvantageous lag in autumn. Spunta and Arinda performed well within each crop season, whereas Ninfa showed an important yield loss in autumn. In both off-season crops, delaying tuber harvest until leaf senescence increased yield and improved quality attributes such as tuber dry matter content and skin colour, whereas nitrate contents significantly decreased in the winter-spring crop and increased in the summer-autumn crop. Ninfa showed less tendency than Arinda and Spunta to accumulate nitrate in tubers in both off-season crops. It might be advantageous to examine in further research which mechanisms sustain compatibility to the autumn and assess other quality characteristics for the fresh market in the contrasting climatic conditions of the two off-season crops. Copyright (c) 2009 Society of Chemical Industry.

Determination of Optimal Harvest Time of Chuchung Variety Green Rice(®) (Oryza sativa L.) with High Contents of GABA, γ-Oryzanol, and α-Tocopherol.

PubMed

Kim, Hoon; Kim, Oui-Woung; Ha, Ae Wha; Park, Soojin

2016-06-01

In our previous study, an early-maturing variety of rice (Oryza sativa L.), Jinbu can have feature with unique green color, various phytochemicals as well as nutritive components by the optimal early harvesting, called Green Rice(®) (GR). The aims of the present field experiments were to evaluate the changes in the weight of 1,000 kernels, yield, and contents of proximate and bioactive compounds in Chuchung, a mid-late maturing variety, during the pre-harvest maturation of rough rice and to research the appropriate harvest time and potent bioactivity of Chuchung GR. The weights of 1,000 kernels of Chuchung GR dramatically increased until 27 days after heading (DAH). The yields of Chuchung GR declined after 27 DAH and significantly declined to 0.0% after 45 DAH. The caloric value and total mineral contents were higher in the GR than in the full ripe stage, the brown rice (BR). In the GR, the contents of bioactive compounds, such as γ-aminobutyric acid, γ-oryzanol, and α-tocopherol, were much higher (P<0.05) than those in the BR, specifically during 24~27 DAH. Therefore, bioactive Chuchung GR can be produced with a reasonable yield at 24~27 DAH and it could be useful for applications in various nutritive and functional food products.

Determination of Optimal Harvest Time of Chuchung Variety Green Rice® (Oryza sativa L.) with High Contents of GABA, γ-Oryzanol, and α-Tocopherol

PubMed Central

Kim, Hoon; Kim, Oui-Woung; Ha, Ae Wha; Park, Soojin

2016-01-01

In our previous study, an early-maturing variety of rice (Oryza sativa L.), Jinbu can have feature with unique green color, various phytochemicals as well as nutritive components by the optimal early harvesting, called Green Rice® (GR). The aims of the present field experiments were to evaluate the changes in the weight of 1,000 kernels, yield, and contents of proximate and bioactive compounds in Chuchung, a mid-late maturing variety, during the pre-harvest maturation of rough rice and to research the appropriate harvest time and potent bioactivity of Chuchung GR. The weights of 1,000 kernels of Chuchung GR dramatically increased until 27 days after heading (DAH). The yields of Chuchung GR declined after 27 DAH and significantly declined to 0.0% after 45 DAH. The caloric value and total mineral contents were higher in the GR than in the full ripe stage, the brown rice (BR). In the GR, the contents of bioactive compounds, such as γ-aminobutyric acid, γ-oryzanol, and α-tocopherol, were much higher (P<0.05) than those in the BR, specifically during 24~27 DAH. Therefore, bioactive Chuchung GR can be produced with a reasonable yield at 24~27 DAH and it could be useful for applications in various nutritive and functional food products. PMID:27390725

Transfer from long to short photoperiods affects production efficiency of day-neutral rice

NASA Technical Reports Server (NTRS)

Goldman, K. R.; Mitchell, C. A.

1999-01-01

The day-neutral, semidwarf rice (Oryza sativa L.) cultivar Ai-Nan-Tsao was grown in a greenhouse under summer conditions using high-pressure sodium lamps to extend the natural photoperiod. After allowing 2 weeks for germination, stand establishment, and thinning to a consistent planting density of 212 plants/m2, stands were maintained under continuous lighting for 35 or 49 days before shifting to 8- or 12-h photoperiods until harvest 76 days after planting. Non-shifted control treatments consisting of 8-, 12-, or 24-h photoperiods also were maintained throughout production. Tiller number increased as duration of exposure to continuous light increased before shifting to shorter photoperiods. However, shoot harvest index and yield efficiency rate were lower for all plants receiving continuous light than for those under the 8- or 12-h photoperiods. Stands receiving 12-h photoperiods throughout production had the highest grain yield per plant and equaled the 8-h-photoperiod control plants for the lowest tiller number per plant. As long as stands were exposed to continuous light, tiller formation continued. Shifting to shorter photoperiods late in the cropping cycle resulted in newly formed tillers that were either sterile or unable to mature grain before harvest. Late-forming tillers also suppressed yield of grain in early-forming tillers, presumably by competing for photosynthate or for remobilized assimilate during senescence. Stands receiving 12-h photoperiods throughout production not only produced the highest grain yield at harvest but had the highest shoot harvest index, which is important for resource-recovery strategies in advanced life-support systems proposed for space.

Harvesting costs and environmental impacts associated with skyline yarding shelterwood harvests and thinning in Appalachian hardwoods

Treesearch

J. E. Baumgras; C. B. LeDoux; J. R. Sherar

1993-01-01

To evaluate the potential for moderating the visual impact and soil disturbance associated with timber harvesting on steep-slope hardwood sites, thinning and shelterwood harvests were conducted with a skyline yarding system. Operations were monitored to document harvesting production, residual stand damage, soil disturbance, and visual quality. Yarding costs for...

Electrochemically driven mechanical energy harvesting.

PubMed

Kim, Sangtae; Choi, Soon Ju; Zhao, Kejie; Yang, Hui; Gobbi, Giorgia; Zhang, Sulin; Li, Ju

2016-01-06

Efficient mechanical energy harvesters enable various wearable devices and auxiliary energy supply. Here we report a novel class of mechanical energy harvesters via stress-voltage coupling in electrochemically alloyed electrodes. The device consists of two identical Li-alloyed Si as electrodes, separated by electrolyte-soaked polymer membranes. Bending-induced asymmetric stresses generate chemical potential difference, driving lithium ion flux from the compressed to the tensed electrode to generate electrical current. Removing the bending reverses ion flux and electrical current. Our thermodynamic analysis reveals that the ideal energy-harvesting efficiency of this device is dictated by the Poisson's ratio of the electrodes. For the thin-film-based energy harvester used in this study, the device has achieved a generating capacity of 15%. The device demonstrates a practical use of stress-composition-voltage coupling in electrochemically active alloys to harvest low-grade mechanical energies from various low-frequency motions, such as everyday human activities.

Electrochemically driven mechanical energy harvesting

PubMed Central

Kim, Sangtae; Choi, Soon Ju; Zhao, Kejie; Yang, Hui; Gobbi, Giorgia; Zhang, Sulin; Li, Ju

2016-01-01

Efficient mechanical energy harvesters enable various wearable devices and auxiliary energy supply. Here we report a novel class of mechanical energy harvesters via stress–voltage coupling in electrochemically alloyed electrodes. The device consists of two identical Li-alloyed Si as electrodes, separated by electrolyte-soaked polymer membranes. Bending-induced asymmetric stresses generate chemical potential difference, driving lithium ion flux from the compressed to the tensed electrode to generate electrical current. Removing the bending reverses ion flux and electrical current. Our thermodynamic analysis reveals that the ideal energy-harvesting efficiency of this device is dictated by the Poisson's ratio of the electrodes. For the thin-film-based energy harvester used in this study, the device has achieved a generating capacity of 15%. The device demonstrates a practical use of stress-composition–voltage coupling in electrochemically active alloys to harvest low-grade mechanical energies from various low-frequency motions, such as everyday human activities. PMID:26733282

Effects of Controlled-Release Fertilizer on Leaf Area Index and Fruit Yield in High-Density Soilless Tomato Culture Using Low Node-Order Pinching

PubMed Central

Kinoshita, Takafumi; Yano, Takayoshi; Sugiura, Makoto; Nagasaki, Yuji

2014-01-01

To further development of a simplified fertigation system using controlled-release fertilizers (CRF), we investigated the effects of differing levels of fertilizers and plant density on leaf area index (LAI), fruit yields, and nutrient use in soilless tomato cultures with low node-order pinching and high plant density during spring-summer (SS), summer-fall (SF), and fall-winter (FW) seasons. Plants were treated with 1 of 3 levels of CRF in a closed system, or with liquid fertilizer (LF) with constant electrical conductivity (EC) in a drip-draining system. Two plant densities were examined for each fertilizer treatment. In CRF treatments, LAI at pinching increased linearly with increasing nutrient supply for all cropping seasons. In SS, both light interception by plant canopy at pinching and total marketable fruit yield increased linearly with increasing LAI up to 6 m2·m−2; the maximization point was not reached for any of the treatments. In FW, both light interception and yield were maximized at an LAI of approximately 4. These results suggest that maximizing the LAI in SS and FW to the saturation point for light interception is important for increasing yield. In SF, however, the yield maximized at an LAI of approximately 3, although the light interception linearly increased with increasing LAI, up to 4.5. According to our results, the optimal LAI at pinching may be 6 in SS, 3 in SF, and 4 in FW. In comparing LAI values with similar fruit yield, we found that nutrient supply was 32−46% lower with the CRF method than with LF. In conclusion, CRF application in a closed system enables growers to achieve a desirable LAI to maximize fruit yield with a regulated amount of nutrient supply per unit area. Further, the CRF method greatly reduced nutrient use without decreasing fruit yield at similar LAIs, as compared to the LF method. PMID:25402478

Harvesting small stems -- A Southern USA perspective

Treesearch

William F. Watson; Bryce J. Stokes

1989-01-01

Operations that harvest small stems using conventional equipment are discussed. A typical operation consists of rubber-tired feller-bunchers with shear heads, rubber-tired grapple skidders, and in-woods chippers. These systems harvest the small stems either in a pre-harvest, postharvest, or integrated-harvest method.

Seasonal variations in harvest index and bacoside A contents amongst accessions of Bacopa monnieri (L.) Wettst. collected from wild populations.

PubMed

Bansal, Mahima; Reddy, M Sudhakara; Kumar, Anil

2016-07-01

Bacoside A, a major active principle of Bacopa monnieri known for its cognitive effects is a mixture of saponins like bacoside A3, bacopaside II, isomer of bacopasaponin C and bacopasaponin C. Seasonal changes in biomass and bacoside A levels in fourteen accessions of B. monnieri were evaluated after maintaining these at a common site at Thapar University campus, Patiala (30°19'36.12″N and 76°24'1.08″E) for 1 year. Harvestable biomass and total bacoside A contents varied significantly between the accessions and also in a particular accession during different seasons of the year. The maximum dry weight of plant (biomass 1.64 g) and bacoside A levels (6.82 mg/plant) were recorded in accession BM1. Harvestable biomass was highest during summer in accessions BM1 and BM7 (FW 4.2 g/plant), whereas bacoside A levels were also highest during summer and in accession BM1 (6.82 mg/plant). The lowest bacoside A level (0.06 mg/plant) was recorded in accession BM14 during winter. Principal component analysis showed that samples of summer were positively correlated with both the components suggesting an appropriate time for the harvest.

Flow Energy Piezoelectric Bimorph Nozzle Harvester

NASA Technical Reports Server (NTRS)

Walkemeyer, Phillip E. (Inventor); Tosi, Phillipe (Inventor); Corbett, Thomas Gary (Inventor); Hall, Jeffrey L. (Inventor); Lee, Hyeong Jae (Inventor); Arrazola, Alvaro Jose (Inventor); Sherrit, Stewart (Inventor); Colonius, Tim (Inventor); Kim, Namhyo (Inventor); Sun, Kai (Inventor)

2016-01-01

A flow energy harvesting device having a harvester pipe includes a flow inlet that receives flow from a primary pipe, a flow outlet that returns the flow into the primary pipe, and a flow diverter within the harvester pipe having an inlet section coupled to the flow inlet, a flow constriction section coupled to the inlet section and positioned at a midpoint of the harvester pipe and having a spline shape with a substantially reduced flow opening size at a constriction point along the spline shape, and an outlet section coupled to the constriction section. The harvester pipe may further include a piezoelectric structure extending from the inlet section through the constriction section and point such that the fluid flow past the constriction point results in oscillatory pressure amplitude inducing vibrations in the piezoelectric structure sufficient to cause a direct piezoelectric effect and to generate electrical power for harvesting.

Harvesting implementation for the GI-cat distributed catalog

NASA Astrophysics Data System (ADS)

Boldrini, Enrico; Papeschi, Fabrizio; Bigagli, Lorenzo; Mazzetti, Paolo

2010-05-01

GI-cat framework implements a distributed catalog service supporting different international standards and interoperability arrangements in use by the geoscientific community. The distribution functionality in conjunction with the mediation functionality allows to seamlessly query remote heterogeneous data sources, including OGC Web Services - e.e. OGC CSW, WCS, WFS and WMS, community standards such as UNIDATA THREDDS/OPeNDAP, SeaDataNet CDI (Common Data Index), GBIF (Global Biodiversity Information Facility) services and OpenSearch engines. In the GI-cat modular architecture a distributor component carry out the distribution functionality by query delegation to the mediator components (one for each different data source). Each of these mediator components is able to query a specific data source and convert back the results by mapping of the foreign data model to the GI-cat internal one, based on ISO 19139. In order to cope with deployment scenarios in which local data is expected, an harvesting approach has been experimented. The new strategy comes in addition to the consolidated distributed approach, allowing the user to switch between a remote and a local search at will for each federated resource; this extends GI-cat configuration possibilities. The harvesting strategy is designed in GI-cat by the use at the core of a local cache component, implemented as a native XML database and based on eXist. The different heterogeneous sources are queried for the bulk of available data; this data is then injected into the cache component after being converted to the GI-cat data model. The query and conversion steps are performed by the mediator components that were are part of the GI-cat framework. Afterward each new query can be exercised against local data that have been stored in the cache component. Considering both advantages and shortcomings that affect harvesting and query distribution approaches, it comes out that a user driven tuning is required to take the best

Light harvesting arrays

DOEpatents

Lindsey, Jonathan S.

2002-01-01

A light harvesting array useful for the manufacture of devices such as solar cells comprises: (a) a first substrate comprising a first electrode; and (b) a layer of light harvesting rods electrically coupled to the first electrode, each of the light harvesting rods comprising a polymer of Formula I: X.sup.1.paren open-st.X.sup.m+1).sub.m (I) wherein m is at least 1, and may be from two, three or four to 20 or more; X.sup.1 is a charge separation group (and preferably a porphyrinic macrocycle, which may be one ligand of a double-decker sandwich compound) having an excited-state of energy equal to or lower than that of X.sup.2, and X.sup.2 through X.sup.m+1 are chromophores (and again are preferably porphyrinic macrocycles).

Triple Hybrid Energy Harvesting Interface Electronics

NASA Astrophysics Data System (ADS)

Uluşan, H.; Chamanian, S.; Pathirana, W. M. P. R.; Zorlu, Ö.; Muhtaroğlu, A.; Külah, H.

2016-11-01

This study presents a novel triple hybrid system that combines simultaneously generated power from thermoelectric (TE), vibration-based electromagnetic (EM) and piezoelectric (PZT) harvesters for a relatively high power supply capability. In the proposed solution each harvesting source utilizes a distinct power management circuit that generates a DC voltage suitable for combining the three parallel supplies. The circuits are designed and implemented in 180 nm standard CMOS technology, and are terminated with a schottky diode to avoid reverse current flow. The harvested AC signal from the EM harvester is rectified with a self-powered AC-DC doubler, which utilizes active diode structures to minimize the forward- bias voltage drop. The PZT interface electronics utilizes a negative voltage converter as the first stage, followed by synchronous power extraction and DC-to-DC conversion through internal switches, and an external inductor. The ultra-low voltage DC power harvested by the TE generator is stepped up through a charge-pump driven by an LC oscillator with fully- integrated center-tapped differential inductors. Test results indicate that hybrid energy harvesting circuit provides more than 1 V output for load resistances higher than 100 kΩ (10 μW) where the stand-alone harvesting circuits are not able to reach 1 V output. This is the first hybrid harvester circuit that simultaneously extracts energy from three independent sources, and delivers a single DC output.

Approaches to automated protein crystal harvesting

PubMed Central

Deller, Marc C.; Rupp, Bernhard

2014-01-01

The harvesting of protein crystals is almost always a necessary step in the determination of a protein structure using X-ray crystallographic techniques. However, protein crystals are usually fragile and susceptible to damage during the harvesting process. For this reason, protein crystal harvesting is the single step that remains entirely dependent on skilled human intervention. Automation has been implemented in the majority of other stages of the structure-determination pipeline, including cloning, expression, purification, crystallization and data collection. The gap in automation between crystallization and data collection results in a bottleneck in throughput and presents unfortunate opportunities for crystal damage. Several automated protein crystal harvesting systems have been developed, including systems utilizing microcapillaries, microtools, microgrippers, acoustic droplet ejection and optical traps. However, these systems have yet to be commonly deployed in the majority of crystallography laboratories owing to a variety of technical and cost-related issues. Automation of protein crystal harvesting remains essential for harnessing the full benefits of fourth-generation synchrotrons, free-electron lasers and microfocus beamlines. Furthermore, automation of protein crystal harvesting offers several benefits when compared with traditional manual approaches, including the ability to harvest microcrystals, improved flash-cooling procedures and increased throughput. PMID:24637746

Impacts of drought on grape yields in Western Cape, South Africa

NASA Astrophysics Data System (ADS)

Araujo, Julio A.; Abiodun, Babatunde J.; Crespo, Olivier

2016-01-01

Droughts remain a threat to grape yields in South Africa. Previous studies on the impacts of climate on grape yield in the country have focussed on the impact of rainfall and temperature separately; meanwhile, grape yields are affected by drought, which is a combination of rainfall and temperature influences. The present study investigates the impacts of drought on grape yields in the Western Cape (South Africa) at district and farm scales. The study used a new drought index that is based on simple water balance (Standardized Precipitation Evapotranspiration Index; hereafter, SPEI) to identify drought events and used a correlation analysis to identify the relationship between drought and grape yields. A crop simulation model (Agricultural Production Systems sIMulator, APSIM) was applied at the farm scale to investigate the role of irrigation in mitigating the impacts of drought on grape yield. The model gives a realistic simulation of grape yields. The Western Cape has experienced a series of severe droughts in the past few decades. The severe droughts occurred when a decrease in rainfall occurred simultaneously with an increase in temperature. El Niño Southern Oscillation (ENSO) appears to be an important driver of drought severity in the Western Cape, because most of the severe droughts occurred in El Niño years. At the district scale, the correlation between drought index and grape yield is weak ( r≈-0.5), but at the farm scale, it is strong ( r≈-0.9). This suggests that many farmers are able to mitigate the impacts of drought on grape yields through irrigation management. At the farm scale, where the impact of drought on grape yields is high, poor yield years coincide with moderate or severe drought periods. The APSIM simulation, which gives a realistic simulation of grape yields at the farm scale, suggests that grape yields become more sensitive to spring and summer droughts in the absence of irrigation. Results of this study may guide decision-making on

Effect of crop residues on soil properties, plant growth, and crop yield. Agronomy Farm, Lincoln, Nebraska

DOE Office of Scientific and Technical Information (OSTI.GOV)

Power, J.F.

1981-01-01

Progress is reported in a study designed to evaluate the effects of quantity of crop residues left on soil surface on soil properties, plant growth, and crop yield and to determine the effects of quantity of surface residues upon soil, fertilizer, and residue N transformations, availability, and efficiency of use. In a dryland corn-sorghum-soybean rotation produced on a clay loam, residues remaining after harvest of the previous crop were removed and respread on plots at rates of 0, 0.5, 1.0, and 1.5 times the quantity of residues originally present. The above crops were planted in four replications the following springmore » without tillage, after broadcasting 50 kg N/ha as ammonium nitrate. In 1980, /sup 15/N-depleted NH/sub 4/NO/sub 3/ was applied to half of each plot. After harvest, crop residues produced on the half-plot receiving the N-isotope were transferred to the half-plot receiving regular fertilizer, and visa versa. In 1981, /sup 15/N-depleted NH/sub 4/NO/sub 3/ was applied to half of each plot again, except at right angles to the fertilizer applied in 1980. After planting each year, thermocouples were installed in each plot and soil temperatures were recorded. Also access tubes were installed in all plots and soil water content was measured to the 150 cm soil depth periodically during the growing season. Dry matter production and N uptake by the plant tissue was measured periodically during the growing season and at maturity. Additional measurements taken included leaf area index, xylem water potentials, and soil microbial populations. Data are presented on corn and soybean production characteristics as affected by rate of crop residue on soil surface. Results are also given on leaf area index (LAI) and dry matter production of corn and soybeans as affected by surface residue rate. Total N content of corn and soybean plant materials and surface residues, and total and inorganic soil N (1980) are reported.« less

Declining scaup populations: A retrospective analysis of long-term population and harvest survey data

USGS Publications Warehouse

Afton, A.D.; Anderson, M.G.

2001-01-01

We examined long-term databases concerning population status of scaup (lesser [Aythya affinis] and greater scaup [A. marila] combined) and harvest statistics of lesser scaup to identify factors potentially limiting population growth. Specifically, we explored evidence for and against the general hypotheses that scaup populations have declined in association with declining recruitment and/or female survival. We examined geographic heterogeneity in scaup demographic patterns that could yield evidence about potential limiting factors. Several biases exist in survey methodology used to estimate scaup populations and harvest statistics; however, none of these biases likely accounted for our major findings that (1) the continental scaup breeding population has declined over the last 20 years, with widespread and consistent declines within surveyed areas of the Canadian western boreal forest where most lesser scaup breed; (2) sex ratios of lesser scaup in the U.S. harvest have increased (more males now relative to females); and (3) age ratios of lesser scaup in the U.S. harvest have declined (fewer immatures now relative to adults), especially in the midcontinent region. We interpreted these major findings as evidence that (1) recruitment of lesser scaup has declined over the last 20 years, particularly in the Canadian western boreal forest; and (2) survival of female lesser scaup has declined relative to that of males. We found little evidence that harvest was associated with the scaup population decline. Our findings underscore the need for both improvements and changes to population survey procedures and new research to discriminate among various hypotheses explaining the recent scaup population decline.

Some harvest options and their consequences for the aspen, birch, and associated forest types of the Lake States.

Treesearch

L.F Ohmann; H.O. Batzer; R.R. Buech; D.C. Lothner; D. A. Perala; A.L. Schipper; E.S. Verry

1978-01-01

Describes some harvest options and their consequences in terms of timber investment return, water yield and quality, wildlife, visual quality, and disease and insect impact for the aspen, white birch, red pine, white pine, jack pine, black spruce, spruce-fir, and white-cedar forest types of the Lake States.

Heat-related symptoms in sugarcane harvesters.

PubMed

Crowe, Jennifer; Nilsson, Maria; Kjellstrom, Tord; Wesseling, Catharina

2015-05-01

Exposure to heat stress is a documented risk for Central American sugarcane harvesters. However, little is known about heat-related illness in this population. This study examined the frequency of heat-related health effects among harvesters (n = 106) exposed to occupational heat stress compared to non-harvesters (n = 63). Chi-square test and gamma statistic were used to evaluate differences in self-reported symptoms and trends over heat exposure categories. Heat and dehydration symptoms (headache, tachycardia, muscle cramps, fever, nausea, difficulty breathing, dizziness, swelling of hands/feet, and dysuria) were experienced at least once per week significantly more frequently among harvesters. Percentages of workers reporting heat and dehydration symptoms increased in accordance with increasing heat exposure categories. A large percentage of harvesters are experiencing heat illness throughout the harvest demonstrating an urgent need for improved workplace practices, particularly in light of climate change and the epidemic of chronic kidney disease prevalent in this population. © 2015 Wiley Periodicals, Inc.

Rainwater harvesting and management in rainfed agricultural systems in sub-Saharan Africa - A review

NASA Astrophysics Data System (ADS)