Early central andean metalworking from mina perdida, peru

Copper and gold artifacts in contexts dated to approximately 3120 to 3020 carbon-14 years before the present ( approximately 1410 to 1090 calendar years B.C.) recovered in excavations at Mina Perdida, Lurin Valley, Peru, show that artisans hammered native metals into thin foils, in some cases with intermediate anneals. They gilded copper artifacts by attaching gold foil. The artifacts show that fundamental elements of the Andean metallurgical tradition were developed before the Chavin horizon, and that on the Peruvian coast the working of native copper preceded the production of smelted copper objects.     

Millwood honeylocust trees: seedpod nutritive value and yield characteristics

The Millwood (MW) cultivar of the honeylocust (Gleditsia triacanthos L.) tree has gained particular interest for silvopasture systems due to the production of edible, high-sugar seedpods that livestock may consume after pod drop. Two studies were conducted within an active sheep and honeylocust silvopasture to (1) estimate nutritional variability of seedpods among MW trees, and to (2) determine seedpod yields and seasonal production variation of MW trees. Seedpods were harvested from each pod-bearing MW in October 2008 and 2009, just prior to pod drop. Nutritional characteristics such as detergent fibers, crude protein, in vitro digestibility, and sugar concentrations were determined for fractionated husk and seed components. Further, MW fodder yields were estimated in 2008, 2009, and 2010 through field measurements and tree yield classification. Both ground husks and seeds were low in fiber (273 and 132 g kg^?1 neutral detergent fiber, respectively) and highly digestible (787 and 963 g kg^?1, respectively). Seed husk sugar concentrations averaged 223 g kg^?1. Based on the nutritive fractions assayed, whole ground MW seedpods grown in Virginia have a nutritional profile comparable to that of ground whole-ear dent corn (Zea mays L.) or oat (Avena sativa L.) grain. Nearly all MW trees displayed some form of alternate-bearing pattern. Average dry matter yields of pod-bearing trees were 15.8, 4.8, and 14.7 kg tree^?1 in 2008, 2009, and 2010, respectively. Pod yield and quality indicate MW honeylocust trees have good potential as fodder-bearing trees in temperate silvopasture systems.     

Assessing the effect of genetic and anatomic variation of Cucurbita rootstocks on vigour,survival and yield of grafted melons

Summary

Melon (Cucumis melo L.) ‘Arava’ was grafted onto 22 experimental Cucurbita rootstocks including intra- or interspecific hybrids to examine scion-rootstock compatibility and to correlate plant performance under greenhouse and field conditions. The commercial Cucurbita ‘TZ-148’ rootstock and non-grafted plants were used as controls. Numbers of leaves, stem length and plant fresh weights were recorded three weeks after planting. Vegetative growth of the grafted plants varied markedly, indicating differences in compatibility between the scion and rootstocks. A positive correlation was found between number of leaves, stem length and fresh weight of melon plants. No significant advantage in vegetative growth was found in melons grafted onto intra- or interspecific hybrid rootstocks. Stem diameter and number of vascular bundles of the rootstock did not correlate with scion plant fresh weight. Twelve selected rootstocks out of the 22 tested were grown in the field during the spring and autumn, to determine if there is an association between the plant performance in the greenhouse and fruit yield under field conditions. Positive and significant correlations were found between greenhouse growth parameters and fruit yield under field conditions. It is suggested that testing grafted melons under greenhouse conditions could be a useful tool for preliminary testing of scion-rootstock compatibility.     

Revisiting the commons: local lessons, global challenges

In a seminal paper, Garrett Hardin argued in 1968 that users of a commons are caught in an inevitable process that leads to the destruction of the resources on which they depend. This article discusses new insights about such problems and the conditions most likely to favor sustainable uses of common-pool resources. Some of the most difficult challenges concern the management of large-scale resources that depend on international cooperation, such as fresh water in international basins or large marine ecosystems. Institutional diversity may be as important as biological diversity for our long-term survival.     

Single-gene resistance to zucchini yellow mosaic virus in Cucurbita moschata

Summary The mode of inheritance for resistance to zucchini yellow mosaic virus (ZYMV) in Cucurbita moschata was determined from F₁, F₂, and backcross progenies of the cross between the susceptible cultivar Waltham Butternut from the U.S.A. and a resistant inbred line of the Menina cultivar from Portugal. Resistance to ZYMV in Menina was conferred by a single dominant gene designated Zym.     

Effects of a 61.7 km ride on magnesium and calcium homeostasis in well trained endurance horses

The adequacy of the dietary supply of Mg and Ca was evaluated in seven well trained endurance horses completing a 61.7 km ride. The horses received excessive amounts of dietary magnesium before and during the ride. Blood samples were taken one hour before the start, at the first and second veterinary gate, directly and 1 and 2 hours after the finish. The mean body weight loss was 20.1 ± 3.9 kg which implied a body weight reduction of 4.6 ± 1.0%. No major downward changes of the concentrations of the total and ionized concentrations of calcium and magnesium and erythrocyte Mg concentrations were observed during the ride in response to the Mg and Ca loss via sweat. Also the concentrations of parathyroid hormone and 1,25-dihydroxyvitamin D were not increased. These results demonstrate that under the conditions of this study sufficient amounts of Mg and Ca were available from the diet, from additional supplementation during the ride and from body stores.     

A comparison of planting and coppice regeneration of Eucalyptus grandis × Eucalyptus urophylla clones in South Africa

Results from two coppice compared to replant trials are presented that originated from clone by site interaction (CSI) trials established on high? and low?productivity sites in subtropical coastal KwaZulu?Natal, South Africa. After the 84?month CSI trial measurements were completed the trees were harvested. Selected plots were allowed to coppice with the remainder replanted to the same four Eucalyptus grandis×Eucalyptus urophylla hybrid clones. Growth was higher at Kwambo Timbers (average mean annual increment [MAI] 34 wet white tonnes [wwt] ha?1 y?1), characterised by a higher mean annual precipitation, than at Palm Ridge (average MAI 11 wwt ha?1 y?1). In these trials coppicing of sufficient stumps per hectare (>1 000 stumps ha?1) resulted in similar volume production on the higher?productivity site and slightly improved (additional 3.4 wwt ha?1 y?1) yield on the lower?productivity site compared with the planted crop. The benefit of coppicing was mainly related to a reduction in the temporary unplanted period and reduced establishment cost. This study showed that coppicing can be a viable, cost?effective alternative to planting in commercial forestry if a number of criteria are met. However, it is recommended that the decision to coppice or to replant should be evaluated on a case?by?case basis.     

Effect of site preparation intensity on the early growth of loblolly pine (Pinus taeda L.) and the incidence of pine tip moth (Rhyacionia spp.)

Twelve, 16-ha study sites were established in recently harvested (1980) stands of natural pine-mixed hardwoods located in the Piedmonts of South Carolina and Georgia. Treatments applied were check (no site preparation), herbicide-burn (3.4 kg ae Glyphosate/ha), chop-burn, shear-disc, shear-V blade-disc, shear-pile, and shear-pile-disc. Measurements collected after two growing seasons included pine height, diameter, and occurrence of pine tip moth (Rhyacionia spp.) infestation on the terminal shoot. After the second growing season, tree volume was 58% greater on mechanically-treated areas compared to the check and herbicide-burn areas. Average pine tip moth incidence was 15% for the check treatment and ranged from 24 to 36% for the other six treatments. Although the disced treatments had higher tip moth infestation (32 to 36%) compared to the check plots (15%), pine growth was significantly greater for treatments involving discing.