Influence of characteristics of irrigation channels on the breeding bird community of a wetland zone in southeast of Spain

The “El Hondo Nature Park” is mainly composed of a series of irrigation channels and water reservoirs, subjected to various regimes of management as well as reed and vegetation control, thus creating a great variety of habitats and situations. To determine the influence of these habitats and management regimes on the local bird community, a set of characteristics of these channels and their surrounding area were analysed with a Correspondence Analysis (CA). The degree of reed development in channels and the presence in the surroundings of orchards and other reed formations were the most decisive factors to explain the probability of occurrence of reed birds and waterbirds, as well as bird species richness and abundance. Other bird species were not directly influenced by channel variables, but only by those of surrounding land uses.

The comparative effectiveness of rodents and dung beetles as local seed dispersers in Mediterranean oak forests

The process of seed dispersal of many animal-dispersed plants is frequently mediated by a small set of biotic agents. However, the contribution that each of these dispersers makes to the overall recruitment may differ largely, with important ecological and management implications for the population viability and dynamics of the species implied in these interactions. In this paper, we compared the relative contribution of two local guilds of scatter-hoarding animals with contrasting metabolic requirements and foraging behaviours (rodents and dung beetles) to the overall recruitment of two Quercus species co-occurring in the forests of southern Spain. For this purpose, we considered not only the quantity of dispersed seeds but also the quality of the seed dispersal process. The suitability for recruitment of the microhabitats where the seeds were deposited was evaluated in a multi-stage demographic approach. The highest rates of seed handling and predation occurred in those microhabitats located under shrubs, mostly due to the foraging activity of rodents. However, the probability of a seed being successfully cached was higher in microhabitats located beneath a tree canopy as a result of the feeding behaviour of beetles. Rodents and beetles showed remarkable differences in their effectiveness as local acorn dispersers. Quantitatively, rodents were much more important than beetles because they dispersed the vast majority of acorns. However, they were qualitatively less effective because they consumed a high proportion of them (over 95%), and seeds were mostly dispersed under shrubs, a less suitable microhabitat for short-term recruitment of the two oak species. Our findings demonstrate that certain species of dung beetles (such as Thorectes lusitanicus), despite being quantitatively less important than rodents, can act as effective local seed dispersers of Mediterranean oak species. Changes in the abundance of beetle populations could thus have profound implications for oak recruitment and community dynamics.

Pollen profiles from a Late Palaeolithic site in the community of Bad Buchau-Kappel, Baden-Wuerttemberg, Germany

Excavations were carried out in a Late Palaeolithic site in the community of Bad Buchau-Kappel between 2003 and 2007. Archaeological investigations covered a total of more than 200 m**2. This site is the product of what likely were multiple occupations that occurred during the Late Glacial on the Federsee shore in this location. The site is situated on a mineral ridge that projected into the former Late Glacial lake Federsee. This beach ridge consists of deposits of fine to coarse gravel and sand and was surrounded by open water, except for a connection to the solid shore on the south. A lagoon lay between the hook-shaped ridge and the shore of the Federsee. This exposed location provided optimal access to the water of the lake. In addition, the small lagoon may have served as a natural harbor for landing boats or canoes. Sedimentological and palynological investigations document the dynamic history of the location between 14,500 and 11,600 years before present (cal BP). Evidence of the deposition of sands, gravels and muds since the Bølling Interstadial is provided by stratigraphic and palynological analyses. The major occupation occurred in the second half of the Younger Dryas period. Most of the finds were located on or in the sediments of the ridge; fewer finds occurred in the surrounding mud, which was also deposited during the Younger Dryas. Direct dates on some bone fragments, however, demonstrate that intermittent sporadic occupations also took place during the two millennia of the Meiendorf, Bølling, and Allerød Interstadials. These bones were reworked during the Younger Dryas and redeposited in the mud. A 14C date from one bone of 11,600 years ago (cal BP) places the Late Palaeolithic occupation of the ridge at the very end of the Younger Dryas, which is in agreement with stratigraphic observations. Stone artifacts, numbering 3,281, comprise the majority of finds from the site. These include typical artifacts of the Late Palaeolithic, such as backed points, short scrapers, and small burins. There are no bipointes or Malaurie-Points, which is in accord with the absolute date of the occupation. A majority of the artifacts are made from a brown chert that is obtainable a few kilometers north of the site in sediments of the Graupensandrinne. Other raw materials include red and green radiolarite that occur in the fluvioglacial gravels of Oberschwaben, as well as quartzite and lydite. The only non-local material present is a few artifacts of tabular chert from the region near Kelheim in Bavaria. A unique find consists of two fragments of a double-barbed harpoon made of red deer antler, which was found in the Younger Dryas mud. It is likely, but not certain, that this find belongs to the same assemblage as the numerous stone artifacts. Although not numerous, animal bones were also found in the excavations. Most of them lay in sediments of the Younger Dryas, but several 14C dates place some of these bones in earlier periods, including the Meiendorf, Bølling, and Allerød Interstadials. These bones were reworked by water and redeposited in mud sediments during the Younger Dryas. As a result, it is difficult to attribute individual bones to particular chronological positions without exact dates. Species that could be identified include wild horse (Equus spec.), moose or elk (Alces alces), red deer (Cervus elaphus), roe deer (Capreolus capreolus), aurochs or bison (Bos spec.), wild boar (Sus scrofa), as well as birds and fish, including pike (Esox Lucius).

The role of the national laboratories in local economic development [microform] : hearing before the Subcommittee on Economic Resources and Competitiveness of the Joint Economic Committee, Congress of the United States, One Hundredth Congress, second session, April 9, 1988.

CIS Microfiche Accession Numbers: CIS 89 J841-5

Planning local solar projects.

"Prepared by Design Alternatives, Inc., Washington, DC, for the Community Services Administration under contract no. B9AF-009."

Size economies in local government services : a review /

Mode of access: Internet.