Summary Woody plants store large quantities of carbon (C) and nutrients. As plants senesce and decay, these stores transfer to the soil or other organisms or are released to the atmosphere. Exogenous factors such as topographic position and microclimatic and edaphic conditions tied to locations affect decay rates; however, we know less about how exogenous relative to endogenous factors such as morphological, anatomical and chemical construction tied to plant species affect these rates, especially across different tissue types. We monitored stem, fine branch and leaf decay over 1 year in ‘rot plots’ distributed across four watersheds in ridge top and valley bottom habitats in a temperate deciduous oak‐hickory forest at Tyson Research Center, MO, USA, in the Ozark Highlands for 21 species of woody plants that vary in their constructions. We found poor coordination across tissues in construction and decay, which likely reflects how functional constraints on living tissues influence recalcitrance to decay. Additionally, for all three tissues, species membership and construction were better predictors of decay than was location. Of the construction traits, chemical composition including total fibre, lignin, cellulose, hemicellulose and concentrations of multiple microelements were the best predictors of decay, although the strength of these relationships differed among tissues. Synthesis. We have long known that rates of biogeochemical cycling are influenced by exogenous factors, such as climatic and edaphic factors. Here, we show across plant tissues that endogenous factors, including species identity and tissue construction, can have stronger controls on rates of decay within our study system than do exogenous factors. However, it is likely that the relative strengths of these different controls change through time and among tissues. We predict that anatomical and morphological controls may be more important at early stages and exogenous factors may be more important at later stages of decay.

Human–wildlife conflicts are common across Africa. In Mozambique, official records show that wildlife killed 265 people during 27 months (July 2006 to September 2008). Crocodile Crocodylus niloticus, lion Panthera leo, elephant Loxodonta africana and hippopotamus Hippopotamus amphibius caused most deaths but crocodiles were responsible for 66%. Crocodile attacks occurred across Mozambique but 53% of deaths occurred in districts bordering Lake Cabora Bassa and the Zambezi River. Hippopotamus attacks were also concentrated here. Lion attacks occurred mainly in northern Mozambique and, while people were attacked by elephants across the country, 67% of deaths occurred in northern Mozambique. Attacks by lions, elephants or hippopotamuses were relatively rare but additional data will probably show that attacks by these species are more widespread than the preliminary records suggest. Buffalo Syncerus caffer, hyaena Crocuta crocuta and leopard Panthera pardus were minor conflict species. Good land-use planning, a long-term solution to many conflicts, is particularly relevant in Mozambique, where the crocodile and hippopotamus populations of protected areas are often in rivers that border these areas, and cause conflicts outside them, and where people commonly live within protected areas. Poverty may prompt fishermen to risk crocodile attack by entering rivers or lakes. The high incidence of conflicts near Limpopo and South Africa’s Kruger National Parks (both within the Great Limpopo Transfrontier Conservation Area) highlights the problems created for people by facilitating the unrestricted movement of wildlife between protected areas across their land.

For 30 years, regular aerial surveys in Zimbabwean protected areas were funded, designed and executed primarily to estimate elephant numbers. Other large herbivores were recorded, even though some species were not easily seen from the air in savannah woodlands. Population estimates for species other than elephant provided indices of abundance that could be used to determine temporal trends in population size. This study tests for significant trends in the abundance of large herbivores in Gonarezhou National Park, assuming that data from aerial sample surveys designed for elephant also provide accurate estimates of real trends in the populations of other herbivores. For each species, the exponential rate of population change was calculated using weighted regression, with the variance of this rate based on the sampling variances of the population estimates. Significant population trends were detected for eight species. Before the 1992 drought, elephant number was held approximately constant by frequent culls, but afterwards, it increased at a mean annual rate of 6.2% (confidence limits 4.0% and 8.6%). Elephants in cow herds increased at 7.3%, significantly faster than elephants in bull herds (−0.5%). Buffalo, eland, kudu, nyala, waterbuck, wildebeest and zebra all increased in number, after population declines during the drought.

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Large mammals were counted in Zambezi alluvial woodlands and on the adjacent ecotone in the north of Mana Pools National Park, Zimbabwe, from April 1981 until October 1989. Densities of all large herbivores on the alluvium in the daytime increased during the dry season. Year‐to‐year variation was studied by comparing end‐of‐dry‐season densities. Flooding of the Zambezi River, controlled by Kariba Dam 100 km upstream, ceased in 1981 and the densities of all species on the alluvium declined in 1982. Rainfall was low in 1982 and very low in 1983 and 1984. The density of buffalo in the study area declined, owing to high mortality and a change in habitat utilization (buffalo herds spent more time in the south of the park). Densities of other species were high during the drought, but the densities of waterbuck, kudu, eland, bushbuck and warthog declined in 1985. Zebra density declined on the ecotone, but not on the alluvium. The densities of eland and kudu increased in 1986 and 1988, respectively, but the densities of the other species were still low in 1989. Impala density on the alluvium in October was related to rainfall during the preceding wet season and was high in drought years. Elephant density declined after a management cull. Rhinoceros density decreased by > 90% during the 1985/6 wet season, as a result of poaching and captures. The long‐term decline in the densities of grazers was probably due primarily to the cessation of flooding by the Zambezi River, rather than to low local rainfall in some years. During the drought, the large grazers (e.g. buffalo) died before the smaller grazers (e.g. warthog). Waterbuck density declined less than the density of other grazers, because waterbuck could cross to vegetated sandbanks in the Zambezi River.

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Summary The bite sizes and bite rates achieved by a tame impala feeding on ten woody browse species were recorded. Mean bite mass was positively correlated with mean leaf mass while mean bite rate was negatively correlated with mean bite mass. The bite rate when feeding on Acacia tortilis was less than expected from the bite size because the impala caught its tongue and lips on the small, curved thorns. This supports the theory that Acacia species are at least partially protected from the effects of ungulate browsing by the presence of thorns, combined with a very small leaf size. RÉSUMEÉ Les tailles et pourcentages des coups de dents provoqués par une impala apprivoisée se nourrissant de dix espàces végétales ligneuses ont été releves. L'importance moyenne du coup de dents est directement proportionnel avec la masse moyenne de la feuille alors que le pourcentage moyen des coups de dents est inversement proportionnel avec l'importance moyenne des coups de dents. Lorsque l'impala se nourrit d'Acacia tortilis, le pourcentage des coups de dents est inférieur à celui attendu d'aprés la taille des coups de dents parce qu'elle se blesse la langue et les lèvres sur les petites epines recourbées. Ceci confirme la théorie selon laquelle les espéces d'Acacia sont au moins partiellement protégées des effets du broutage des ongulés par la présence des épines en combinaison avec la très petite taille des feuilles.

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