Coppice Harvesting of Fuelwood Species on a South African Common: Utilizing Scientific and Indigenous Knowledge in Community Based Natural Resource Management

The limitations of Community Based Natural Resource Management (CBNRM) with respect to the difficulties of comparing local versus scientific knowledge categories within a bounded definition of ‘community’ were investigated by means of a study exploring local indigenous knowledge pertaining to harvesting technique, and the impact of soil and species type on the post-harvest coppice response of popular savanna fuelwood species, among rural inhabitants of the Bushbuckridge region of the Limpopo Province, South Africa. Soils and plants were evaluated chiefly in terms of their perceived ability to retain precipitation, making rainfall a driving force in local understanding of environmental productivity. Some indigenous knowledge showed an agreement with biological data, but overall the variability in responses, as well as the diverse scales at which indigenous and scientific knowledge is directed, were too great to allow for simplistic parallels between local ecological indices to be made. Indigenous environmental knowledge was underscored by the perceived symbolic link between environmental and social degradation. It is recommended that environmental managers incorporate indigenous knowledge as a component of a systems-level approach to natural resource management, where biological, cultural, economic, and symbolic aspects of natural resource use are nested within a broader ecosocial system. This approach to indigenous knowledge is offered as an alternative to the simple scientific evaluation that so often characterizes environmental management.     

Distribution of dominant arbuscular mycorrhizal fungi among five plant species in undisturbed vegetation of a coastal grassland

Most plant species in mixed grassland vegetation are colonized by arbuscular mycorrhizal (AM) fungi. Previous studies have reported differences in host preferences among AM fungi, although the fungi are known to lack host specificity. In the present study, the distribution of phylogenetic groups of AM fungi belonging to a clade of Glomus species was studied in five plant species from a coastal grassland in Denmark. The occurrence of the fungi was determined by PCR analyses of fungal large subunit ribosomal DNA sequences amplified from root fragments using a specific primer set. The results showed that the dominant Glomus species were able to colonize all the studied plant species, supporting the view that the AM fungi represent a large underground interconnecting mycelial network.     

枣园生态系统中害虫与天敌群落演替规律的研究

通过对太谷地区枣园害虫天敌群落的系统调查,并应用最优分割法.主分量分析法和1维和2维排序法,探讨了引起枣园害虫和天敌群落演替的主要类群及其演变规律.结果表明,群落具有明显的主导因子和时序演替格局,枣园害虫和天敌群落在前3个主分量上的变动较大,且跟随效应明显;枣园害虫和天敌群落的演替在时间过程中明显分为4个阶段:枣树发芽前、枣树展叶开花期、枣树结果期、枣果着色成熟期;利用主分量分析法,明确了主要害虫及其天敌的种类.     

A null model of guild proportionality,applied to stratification of a New Zealand temperate rain forest

Summary Much ecological theory assumes that the number of species that can coexist (by species packing) is limited, because competitive exclusion occurs when any pair of species within a guild is too similar — species saturation or niche limitation. If such niche limitation occurs, the proportion of species in each guild should be relatively constant — guild proportionality. This concept is applied to the guilds represented by strata in a forest. A method is produced, and used to examine a New Zealand temperate rain forest. Most strata showed no deviation from a null model of no niche limitation, i.e. no tendency to guild proportionality. The proportion of lianes was more variable than in the null model, tending to be inversely related to the proportion of epiphytes, Canopy tree proportion was significantly more constant than in the null model, but this could be interpreted as a limit caused by the size of a canopy tree individual.     

Palaeocommunity Dynamics and Behavioral Analysis of Conichnus: Bhuj Formation (Lower Cretaceous),Kachchh-India

A palaeocommunity of large Conichnus conicus, a conical, cone-in-cone shaped burrow, created by sea anemones, occurs in medium-grained, crossbedded, well-sorted sandstone in the middle part of the Cretaceous Guneri Member of the Bhuj Formation in India. The trace fossil Conichnus is considered to be a common element of the Skolithos ichnofacies and is interpreted to reflect equilibrium movement in response to substrate aggradation. In the present study, three different varieties of Conichnus conicus are distinguished based on morphology and internal fabric. Community dynamics and burrowing behavior are revealed by inter-burrow relationships, burrow initiation levels and sedimentology. Three types of behavior are envisaged: retrusive equilibrium, protrusive equilibrium response, and escape behavior. Palaeocommunity dynamics show that the tracemakers consisted of only adult organisms that initiated burrows during neap tides and are adapted to feed effectively during weak flow conditions. The occurrence of Conichnus palaeocommunity in the Guneri Member indicates the tidal conditions in a fully marine setting. Results presented herein may aid in the understanding of palaeocommunity dynamics in other shallow marine sequences.     

Functional diversity decreases with temperature in high elevation ant fauna

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Studies on the Population and Community Characteristics in Platycladus orientalis Forest

The population and community characteristics in the Platycladus orientalis forest on Qianfo Mountain in Jinan are studied. The specific composition, spatial pattern, biological spectrum and main species dispersions are reported. It is found that all the main species dispersions are aggregated. The diversity of Shannon-Wiener and Simpson indexes are markedly not correlated with the habitat factors. The patch indexes and niche breadths of the main species have been analysed on such axes as light, soil water and soil organic matter. The value of niche overlap between every two species is high on soil resource axis.     

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The gap theory in forest dynamics

Since the late 1970s, ecologists interested in forest dynamics have focused their attention to the responses of individuals, populations and communities to “gaps” which are openings created in the forest canopy. This review intended to introduce some collective knowledge on major subjects of the gap theory in forest dynamics, in relation to gap-disturbance regimes, tree regeneration behaviour and community structure.