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We observed bees visiting bean (Phaseolus vulgaris) flowers, the most widely grown crop in farmland near Kakamega forest, Kenya, which has attracted interest due to the presence of the only remaining tropical rain forest in the country. Two transects were created in the north and south of the forest extending to about eight km into the farmland. Observations were carried out on 14 sites on either side of the forest during the flowering period from April to June in 2005 and 2006. We recorded bees belonging to 20 species visiting beans. The honey bee Apis mellifera L. was the most abundant, followed by two solitary bees, Xylocopa calens and Xylocopa incostans. Bee density was low in the farmland in both sides of the forest, but diversity was significantly (P < 0.05) higher in the southern than in the northern transect. One reason for this is that the southern side is heavily populated so hedges and other land are under higher pressure, giving bees no alternative to crop flowers, whilst in the north, the population is low so there is still much land and hedges for alternative food for bees. Hedge management could be improved to support bees, especially when crops are not in flower, by interconnecting the hedges with the forest, so bees will be able to seek refugia and other needs in the forest and be able to provide pollination in the farmland, hence contributing to food security in the country.

Die zuverlassige Versorgung mit Frischwasser ist eine der grosten globalen Herausforderungen. V.a. in Wasserkrisenregionen muss deshalb das Management von Wasserressourcen okonomisch effizient, okologisch nachhaltig, und sozialvertraglich sein. Ein wichtiger Bereich der Wasserversorgung ist die Verbesserung der Lebensmittelsicherheit durch Absicherung des Bewasserungslandbaus nach den oben genannten Prinzipien. Weltweit hat sich die bewasserte Flache in hundert Jahren fast versechsfacht. Rund 40 Prozent aller Nahrungsmittel werden mit kunstlicher Bewasserung erzeugt.

Increased knowledge about the spatial distribution of cotton (Gossypium hirsutum L.) yield in the Khorezm region in Uzbekistan supports the optimal allocation of resources. This research estimated the spatial distribution of cotton yields in Khorezm by integrating remote sensing, field data, and modeling. The agro-meteorological model used was based on Monteith’s biomass production model with multitemporal MODIS (Moderate Resolution Imaging Spectroradiometer)- derived parameters from 2002 as primary inputs. The photosynthetically active radiation (PAR) and environmental stress scalars on crop development were estimated with meteorological information. Using high-spatial-resolution Landsat 7 ETM+ images, the cotton area was extracted and the cotton fraction determined within the coarse spatial resolution MODIS pixels. The spatial resolution of the MODISFPARdata was improved by using an empirical relationship to the higher-resolution MODIS NDVI (Normalized Difference Vegetation Index) data. The estimated raw cotton yield ranged from 1.09 to 3.76 Mg ha -1 . The modeling revealed a spatial trend of higher yields in upstream areas and in locations closer to the irrigation channels and lower yields in downstream areas and at sites more distant to the channels. The validated yield estimations showed a 10% deviation from official governmental statistics. The established agro-meteorological model based on freely available MODIS data and a minimum of field data input is a promising technique for economic and operational lateseason estimation of spatially distributed cotton yield over large regions on which management adjustments could be made.

Soil degradation is one of the most serious environmental problems. Soils represent a resource that is essential to life on this planet (Hillel, 2001). They are the interface between rocks, biota, water and the atmosphere and are therefore a pivotal element of ecosystems. Dryland soils are particularly vulnerable (Katyal and Vlek, 2000) — a problem recognized by the establishment of the Convention to Combat Desertification (www.unccd.org) in 1994. Seventy to 80% of the world’s drylands are affected by desertification. The degradation of soils is typically a ‘creeping environmental problem’ (CEP); i.e., a cumulative environmental change that evolves at an imperceptibly slow pace, which hinders the initiation of counterbalancing measures (Glantz, 1998). Soil losses have been increasing with the growth of the human population. It is particularly troubling that soils today are destroyed at a much faster rate than they can be formed by natural processes.

Flight phenology, mating behavior, colony foundation and the architecture of the initial "royal chamber" of alates of Syntermes spinosus, a common Central Amazonian leaf-feeding, soil-inhabiting termite, are described. Alate swarming occurs throughout the year, and is probably related to rainfall. The alates of this species dig the initial chamber directly into the soil.

A preferência alimentar de cinco espécies de térmitas xilófagos do gênero Nasutitermes que coexistem nas florestas alagáveis da várzea do Rio Solimões/Amazonas por espécies de madeira sã e por madeira em diferentes estágios de decomposição foi avaliada em testes de laboratório. Madeira de baixa densidade foi geralmente preferida; os estágios de decomposição foram preferidas sobre a madeira sã. As cinco espécies de térmitas diferem na amplitude de sua escolha, o que indica uma diferenciação forte entre ela na escolha do alimento. Estas diferenças na preferência alimentar podem ser um fator separador de nicho para as espécies de Nasutitermes da várzea. The alimentary preferences of five species of wood-feeding termites of the genus Nasutitermes that coexist in the inundated forests of the floodplains of the Amazon river várzea for species of fresh wood and for wood in different stages of decomposition was evaluated in laboratory tests. Wood of low density was generally preferred; the decay stages were preferred over fresh wood. The five termite species differ in the amplitude of their choices, indicating a strong differentiation in food choice among them. Differences in feeding preferences may be a niche-separating factor for these five Nasutitermes species of the floodplains.

As espécies comedoras de folhas Syntermes molestus and S. spinosus são duas espécies de cupins dominantes na Reserva Ducke na Amazônia Central; duas outras espécies (S. aculeosus, S. longiceps) existem na área. Todas as espécies (exceto S. aculeosus) são encontradas também em áreas urbanas. O peso seco médio do corpo dos operários de S. molestus e S. spinosus é de 4,5±0,2 e 13,1±1,4 mg, e dos soldados é de 8,2±0,2 and 51,0±1,7 mg, respectivamente. Por isto, S. spinosus está entre os maiores cupins do mundo. Em ambas espécies, o peso fresco é cerca de 4,7 vezes mais alto que o peso seco (uma proporção maior que em outras espécies de cupins). A biomassa das populações de ambas espécies foi avaliada em cerca de 1 g m-2 (peso seco; estimativa indireta), o que eleva estimativas anteriores da biomassa total de térmitas em cerca de 36-45%, a um valor de 3,0-3,5 g m-2. The leaf-feeding species Syntermes molestus and S. spinosus are two dominant termite species in Reserva Ducke in Central Amazonia; two other species (S. aculeosus, S. longiceps) exist in the area. All species except S. aculeosus were also found in urban areas. The workers of S. molestus and S. spinosus have average body dry weights of 4.5±0.2 and 13.1±1.4 mg, and the weight of their soldiers is 8.2±0.2 and 51.0±1.7 mg, respectively. Therefore, S. spinosus is among the largest termites of the world. In both species, fresh weight is about 4.7 higher than dry weight (a wider relation than in other termite species). The biomass of the populations of both species amounted to about 1 g m-2 (dry weight; indirect estimate), which rises previous assessments of the total termite biomass by about 36-45%, to a value of 3.0-3.5 g m-2.

Methane (CH4) is an important greenhouse gas that also affects the chemistry and oxidation capacity of the atmosphere (Cicerone and Oremland 1988). The current burden of methane in the atmosphere is about 4700Tg (1 Tg =1 million tons) (Wahlen et al. 1989), and the global annual emission is ca. 505 Tg CH4 year−1 (Crutzen 1991). Ca. 80% of the total methane emission is of modern biogenic origin, whereas only 20% is due to fossil carbon sources (Wahlen et al. 1989). The increase in the tropospheric methane concentration from 0.7 ppm in preindustrial times to the present value of 1.7 ppm can be attributed mainly to expanding agricultural activities, such as rice cultivation and animal husbandry (Bouwman 1989). Natural wetlands are the largest source of atmospheric methane; the estimated global source strength is ca. 110 Tg CH4year−1 of which ca. 60% is attributed to tropical wetlands (Bartlett and Harriss 1993). However, the strengths of individual sources of atmospheric methane can only be estimated with broad ranges of uncertainty.

The contribution of termites to the global methane budget has been controversely discussed in the last decade. We measured methane emissions from nests of wood-feeding termite species (Nasutitermes spp.) of primary and secondary forests of Amazonia. The methane emission rates from single termite nests varied in a broad range between 0.01 and 9.4 mg CH4 hour−1 nest−1 (average = 2.0 ± 2.4 mg CH4 hour−1 nest−1), as termite colonies vary considerably in size (biomass). Consequently, data given as methane emission per nest are unsuitable for interspecific comparison. In seek for an appropriate unit the methane flux was related to the biomass of the termites dwelling in the nest. On this basis, the variation between the methane emissions of the nests was far lower (0.4 – 4.9 μg hour−1 g termites−1). Biomass-related methane emission rates averaged 3.0 ± 1.3 μg hour−1 g termites−1, which means that Amazonian termites release significantly (at p = 0.01%) more methane than species from other regions. By extrapolating these emission rates to the estimated global biomass of termites we calculated a total emission of 26 Tg CH4 year−1, which represents about 5 % of the annual methane flux from all sources to the world atmosphere. Termites are unlikely to contribute essentially to the global budget of the “greenhouse gas” methane.

To assess the role of termite populations in the change of global atmospheric methane concentrations, we re­ evaluate the hypothesis that deforestation leads to higher populations of wood-feeding termites and to a significant increase of termite-emitted methane in areas of cleared and burned fonner primary rain forest. Calculations are based on a model that uses literature infonnation on tennite population size in primary forest and pasture 1 to I 0 years after forest conversion, wood consumption and methane emission rates of termites. We use two scenarios based on low- and high-end parameters based on data from rain forests in Brazilian Amazonia. In the low-end scenario, termite population biomass is 25 kg·ha· 1 in primary forest; 4 kg·ha· 1 in year I after forest clearing, 51 kg·ha· 1 in a six-year-old pasture, and 4 kg·ha- 1 in a ten-year-old pasture. In the high-end scenario, all values are doubled and the initial breakdown in year 1 is omitted. Wood consumption rates are 49 and 270 mg wood·g termitU·day- 1 , and methane emission rates are 0.0023 and 0.0079 t of carbon released as methane per ton of carbon consumed, in the low- and the high-end scenario, respectively. In the low-end scenario no significant difference exists between the average termite population size in primary forest and pasture modeled over a ten-year period. In the high-end scenario the average population size of years 1-10 after clearing is only 31 % over that of primary forest. The population model data combined with the wood consumption rates allow for only 2.3-32.3% of the wood biomass left from forest burn to be consumed by termites within 10 years. The changes in methane emissions from termite population change after deforestation were calculated using two approaches: "Cumulative net emissions" for the region, which measure the I 0-year impact of a year's forest clearing (e.g. 1.38· 10 6 ha in 1990), increase by 0.000 I to 0. 11 Tg CH4 in the 10 year-period in both scenarios, a negligt"ble contribution to the increase of atmospheric methane concentrations of 45 Tg·yr· 1 • The "annual balance of net methane emissions" from termites in all the different landscapes existing in the whole region in a single year (1990) increases by only 0.004 to 0.33 Tg CH4 (low- and high-end scenario) because of the large proportion of old clearings (>10 years old) with low methane emission rates. Termite populations do not tend to increase as a function of the available wood mass only and therefore methane emissions from termites in cleared areas of former rain forest do not make a significant contribution to the increase of the global methane concentrations in the atmosphere. Copyright © 1996 Elsevier Science Ltd

Points a retenirLa restauration des terres se produira dans un contexte de changement climatique. Differents systemes de connaissances sont necessaires pour avancer parmi les incertitudes et planifier l'adaptation.L'emergence d'ecosystemes inedits represente un defi pour la restauration des terres en raison des inconnus qui les caracterisent.Cet infobrief presente des resultats de recherches liant la restauration des terres a l'adaptation societale et propose un cadre conceptuel de l'adaptation transformative.Il liste egalement une serie de questions pour explorer differentes visions du changement afin de planifier l'adaptation et la restauration.

The genus richness of the termite fauna of a semiarid area (caatinga) in Northeastern Brazil was investigated in the dry season of 1996 and the rainy season of 1998. Eight genera belonging to three termite families (Termitidae, Rhinotermitidae and Kalotermitidae) were found in assessments of termite nests and mounds, investigation of dead wood, and cardboard baits buried 10 cm deep in the soil. The nestbuilder guild was represented by only three genera: Nasutitermes, Constrictotermes and Microcerotermes. Their density (about 1-3 nests ha-1) was very low. In mounds of Constrictotermes, the genus Inquilinitermes is almost invariably found as an inquiline. During the dry season of 1996, wood-inhabiting Kalotermitidae (Neotermes sp.) were abundant in dead branches still attached to the trees. In dead wood on the ground we recorded Heterotermes of the Rhinotermitidae, and Amitermes and Termes of the Termitidae. A relatively high activity of Heterotermes on the baits was recorded within 3 months of exposure. Thus, this site is characterized by a very low genus diversity of termites; nest builders are rare, but soil- and wood-dwelling species are highly active in spite of the adverse conditions (drought) which reign during the larger part of the year.

Hazardous polycyclic aromatic hydrocarbons (PAHs) widely occur in the environment and are believed to be mainly anthropogenic. Here we present strong indications for large biological sources of the PAHs naphthalene, perylene, and possibly also phenanthrene in the Amazonian basin. Termite nests, plant wood, and soils were sampled. Naphthalene is detected in plant wood and is accumulated in the nests of termites from the genus Nasutitermes. Perylene is found in all studied termite nests including six different genera. Phenanthrene occurs at substantial concentrations in wood, soil, and termite nests. Biologische Quellen von polyzyklischen aromatischen Kohlenwasserstoffen (PAK) im Regenwald des Amazonasbeckens Gesundheitsschadliche PAK sind in der Umwelt weit verbreitet. Es wird angenommen, dass sie uberwiegend aus anthropogenen Quellen stammen. In dieser Arbeit weisen wir bedeutende biologische Quellen von Naphthalin und Perylen und moglicherweise auch von Phenanthren im Amazonasbecken nach. Termitenbauten, Holz von Pflanzen und Boden wurden beprobt. Naphthalin ist in erhohten Gehalten im Holz zu finden und ist in den Bauten der Termitengattung Nasutitermes akkumuliert, Perylen ist in allen untersuchten Proben von Nestern sechs unterschiedlicher Termitengattungen nachzuweisen. Phenanthren kommt in nennenswerten Gehalten in Holz, Boden und Termitennestern vor.

Background Increasingly, forests are on the international climate change agenda as land use and cover changes drive forest and carbon loss. The ability of forests to store carbon has created programs such as Reducing Emissions from Deforestation and Degradation plus (REDD+), in order to provide incentives for particular land uses and forest management practices. A critical element to REDD+ is the ability to know the carbon-storage potential of an ecosystem, and the factors likely to affect the rate of carbon accumulation or the maximum amount stored. Most REDD+ initiatives have focused on humid tropical forests because of their large stocks per unit area. Less attention has been paid to the carbon-storage potential of tropical dry forests, woodlands and savannas. Although these ecosystems support a lower biomass per unit area, they are more widespread than humid forests. This proposed systematic review examines miombo woodlands, which are the most extensive vegetation formation in Africa and support over 100 million people. We ask: To what extent have changes in land use and land cover influenced above- and below-ground carbon stocks of miombo woodlands since the 1950s? Methods We will search systematically for studies that document the influence of land use and cover change on above and below ground carbon in miombo woodlands since the 1950s. We will consult bibliographic databases and an extensive grey literature network, including government reports and forestry offices. Relevant studies will examine the impacts of human activities, fire and other land use or cover changes that affect wood biomass or soil carbon in the miombo region. All included studies will be assessed for the soundness and scientific validity of their study design. A quantitative synthesis will tabulate estimates of various parameters necessary to assess carbon stocks and changes across climate and geological factors; and a qualitative analysis will describe the governing land and forest policies. Understanding the impact that land uses and the associated changes have on carbon storage in the miombo woodlands will contribute to more informed forest management policies and better guided strategies for the United Nations Framework Convention on Climate Change.