Johan A. Oldekop

Peer assessment of oral presentations: effects of student gender, university affiliation and participation in the development of assessment criteria

Peer assessment provides a useful mechanism to develop many positive qualities in students studying in higher education (HE). Potential influences on peer‐awarded marks include student qualities such as gender, HE background (e.g. university affiliation) and participation in the development of the assessment criteria. Many studies that have investigated peer assessment have placed great emphasis on marks from a single tutor, or very few tutors, from a single university. This study examined grades awarded by 11 tutors (affiliated with four universities) to oral presentations delivered on a residential field course by second‐year undergraduate students from two universities studying environmental or biological disciplines. Student assessors awarded marks of fairly high precision (correlating strongly with tutor grades) but averaged 5% higher than their tutors (i.e. of only moderate accuracy). Marginally higher marks (circa 1.6%) were awarded by student assessors to speakers studying at the same university. Gender influences were detected as males tended to grade other male speakers very slightly more highly than female speakers. Marks from females were unaffected by speaker gender. Students who participated in the development of the assessment criteria did not achieve higher grades for their presentations. However, when these ‘participants’ were assessing, they awarded lower marks than their peers (i.e. closer to, but not as low as, those awarded by tutors). Lower marks were also awarded during the middle of sessions, possibly resulting from factors associated with motivation and attention of speakers and markers. Overall, the potential biases in marking by naive assessors examined in this study may influence the validity of marks generated by peer assessment schemes, but the experience of this type of assessment had positive effects on those involved.

Understanding the lessons and limitations of conservation and development

The lack of concrete instances in which conservation and development have been successfully merged has strengthened arguments for strict exclusionist conservation policies. Research has focused more on social cooperation and conflict of different management regimes and less on how these factors actually affect the natural environments they seek to conserve. Consequently, it is still unknown which strategies yield better conservation outcomes? We conducted a meta-analysis of 116 published case studies on common resource management regimes from Africa, south and central America, and southern and Southeast Asia. Using ranked sociodemographic, political, and ecological data, we analyzed the effect of land tenure, population size, social heterogeneity, as well as internally devised resource-management rules and regulations (institutions) on conservation outcome. Although land tenure, population size, and social heterogeneity did not significantly affect conservation outcome, institutions were positively associated with better conservation outcomes. There was also a significant interaction effect between population size and institutions, which implies complex relationships between population size and conservation outcome. Our results suggest that communities managing a common resource can play a significant role in conservation and that institutions lead to management regimes with lower environmental impacts.

BIOFRAG - a new database for analyzing BIOdiversity responses to forest FRAGmentation

Habitat fragmentation studies have produced complex results that are challenging to synthesize. Inconsistencies among studies may result from variation in the choice of landscape metrics and response variables, which is often compounded by a lack of key statistical or methodological information. Collating primary datasets on biodiversity responses to fragmentation in a consistent and flexible database permits simple data retrieval for subsequent analyses. We present a relational database that links such field data to taxonomic nomenclature, spatial and temporal plot attributes, and environmental characteristics. Field assessments include measurements of the response(s) (e.g., presence, abundance, ground cover) of one or more species linked to plots in fragments within a partially forested landscape. The database currently holds 9830 unique species recorded in plots of 58 unique landscapes in six of eight realms: mammals 315, birds 1286, herptiles 460, insects 4521, spiders 204, other arthropods 85, gastropods 70, annelids 8, platyhelminthes 4, Onychophora 2, vascular plants 2112, nonvascular plants and lichens 320, and fungi 449. Three landscapes were sampled as long-term time series (>10 years). Seven hundred and eleven species are found in two or more landscapes. Consolidating the substantial amount of primary data available on biodiversity responses to fragmentation in the context of land-use change and natural disturbances is an essential part of understanding the effects of increasing anthropogenic pressures on land. The consistent format of this database facilitates testing of generalizations concerning biologic responses to fragmentation across diverse systems and taxa. It also allows the re-examination of existing datasets with alternative landscape metrics and robust statistical methods, for example, helping to address pseudo-replication problems. The database can thus help researchers in producing broad syntheses of the effects of land use. The database is dynamic and inclusive, and contributions from individual and large-scale data-collection efforts are welcome.

Testing the accuracy of non-experts in biodiversity monitoring exercises using fern species richness in the Ecuadorian Amazon

Assessing environmental change is often constrained by time, money and expertise. Community-based monitoring schemes attempt to address these limitations by providing local communities with the skills to measure changes in natural resources and contribute locally relevant information for local and regional management decisions. Despite the increasing popularity of community-based monitoring schemes, there is little information about the accuracy of the data they produce. In this study we use visual guides and hands-on training to teach groups of leaders from local communities in the Ecuadorian Amazon to measure the species richness of ferns. We compare their results to data obtained by experienced field biologists and show strong positive correlations in species richness estimates between the results obtained by groups receiving visual guides, groups receiving hands-on training and biologists. Our results show that, even with relatively little training, communities can use simple and cost-effective methodologies to yield data that accurately reflect levels of species richness.

The data not collected on community forestry.

Abstract Conservation and development practitioners increasingly promote community forestry as a way to conserve ecosystem services, consolidate resource rights, and reduce poverty. However, outcomes of community forestry have been mixed; many initiatives failed to achieve intended objectives. There is a rich literature on institutional arrangements of community forestry, but there has been little effort to examine the role of socioeconomic, market, and biophysical factors in shaping both land‐cover change dynamics and individual and collective livelihood outcomes. We systematically reviewed the peer‐reviewed literature on community forestry to examine and quantify existing knowledge gaps in the community‐forestry literature relative to these factors. In examining 697 cases of community forest management (CFM), extracted from 267 peer‐reviewed publications, we found 3 key trends that limit understanding of community forestry. First, we found substantial data gaps linking population dynamics, market forces, and biophysical characteristics to both environmental and livelihood outcomes. Second, most studies focused on environmental outcomes, and the majority of studies that assessed socioeconomic outcomes relied on qualitative data, making comparisons across cases difficult. Finally, there was a heavy bias toward studies on South Asian forests, indicating that the literature on community forestry may not be representative of decentralization policies and CFM globally.

Parasitoid wasps influence where aphids die via an interspecific indirect genetic effect

Host–parasite interactions are a key paradigm for understanding the process of coevolution. Central to coevolution is how genetic variation in interacting species allows parasites to evolve manipulative strategies. However, genetic variation in the parasite may also be associated with host phenotype changes, thereby changing the selection on both species. For instance, parasites often induce changes in the behaviour of their host to maximize their own fitness, yet the quantitative genetic basis for behavioural manipulation has not been fully demonstrated. Here, we show that the genotype of the parasitoid wasp Aphidius ervi has a significant effect on where its aphid host Acyrthosiphon pisum moves to die following parasitism, including the likelihood that the aphid abandons the plant. These results provide a clear example of an interspecific indirect genetic effect whereby the genetics of one species influences the expression of a specific behavioural trait in another.

Co-Occurrence Patterns of Common and Rare Leaf-Litter Frogs, Epiphytic Ferns and Dung Beetles across a Gradient of Human Disturbance

Indicator taxa are commonly used to identify priority areas for conservation or to measure biological responses to environmental change. Despite their widespread use, there is no general consensus about the ability of indicator taxa to predict wider trends in biodiversity. Many studies have focused on large-scale patterns of species co-occurrence to identify areas of high biodiversity, threat or endemism, but there is much less information about patterns of species co-occurrence at local scales. In this study, we assess fine-scale co-occurrence patterns of three indicator taxa (epiphytic ferns, leaf litter frogs and dung beetles) across a remotely sensed gradient of human disturbance in the Ecuadorian Amazon. We measure the relative contribution of rare and common species to patterns of total richness in each taxon and determine the ability of common and rare species to act as surrogate measures of human disturbance and each other. We find that the species richness of indicator taxa changed across the human disturbance gradient but that the response differed among taxa, and between rare and common species. Although we find several patterns of co-occurrence, these patterns differed between common and rare species. Despite showing complex patterns of species co-occurrence, our results suggest that species or taxa can act as reliable indicators of each other but that this relationship must be established and not assumed.

Information Flows in Community-Based Monitoring Exercises in the Ecuadorian Amazon

Community-based monitoring schemes provide alternatives to costly scientific monitoring projects. While evidence shows that local community inhabitants can consistently measure environmental changes, few studies have examined how learned monitoring skills get passed on within communities. Here, we trained members of indigenous Kichwa communities in the Ecuadorian Amazon to measure fern and dung beetle species richness and examined how well they could pass on the information they had learned to other members of their community. We subsequently compared locally gathered species richness data to estimates gathered by trained biologists. Our results provide further evidence that devolved monitoring protocols can provide similar data to that gathered by scientists. In addition, our results show that local inhabitants can effectively pass on learned information to other community members, which is particularly important for the longevity of community-based monitoring initiatives.

Linking Brazil’s food security policies to agricultural change

Poverty, food security, and sustainability are intimately intertwined, driving conflict and synergy between environmental and societal concerns. Brazil’s flagship food security policies were implemented over a decade ago to address these issues simultaneously. Global institutions have pledged over 2 million US

A global assessment of the social and conservation outcomes of protected areas.

to develop similar programs in sub-Saharan Africa, yet empirical assessments of many aspects of these policies are still lacking. We focus on a case study in the state of Minas Gerais and assess the agricultural and environmental impacts of the Purchase with Simultaneous Donation (PSD) program. The PSD provides stable markets as incentives to diversify production, but we find no effect of participation on changes in local agricultural practices, production or income. While some farms are expanding, regional agricultural production appears to be declining due to local economic development and related shortages in farm labor. The PSD’s limited impact arises because most farmers only participate irregularly, typically during the dry season when the program offers higher prices than the local market price. Furthermore, participation is constrained by the specific nature of PSD contracts and centralized governance of the program. We complement these findings with data from the Brazilian Ministry of Social Development and the 2006 agricultural census, which show substantial variation in the availability of PSD initiatives, and the funding allocated to them at local, regional and national levels. We suggest that adaptive management strategies that can respond to local market conditions could lead to more equitable and efficient food security and agricultural policies in Brazil and elsewhere.