Quantifying the sampling error in tree census measurements by volunteers and its effect on carbon stock estimates

A typical way to quantify aboveground carbon in forests is to measure tree diameters and use species-specific allometric equations to estimate biomass and carbon stocks. Using "citizen scientists" to collect data that are usually time-consuming and labor-intensive can play a valuable role in ecological research. However, data validation, such as establishing the sampling error in volunteer measurements, is a crucial, but little studied, part of utilizing citizen science data. The aims of this study were to (1) evaluate the quality of tree diameter and height measurements carried out by volunteers compared to expert scientists and (2) estimate how sensitive carbon stock estimates are to these measurement sampling errors. Using all diameter data measured with a diameter tape, the volunteer mean sampling error (difference between repeated measurements of the same stem) was 9.9 mm, and the expert sampling error was 1.8 mm. Excluding those sampling errors >1 cm, the mean sampling errors were 2.3 mm (volunteers) and 1.4 mm (experts) (this excluded 14% [volunteer] and 3% [expert] of the data). The sampling error in diameter measurements had a small effect on the biomass estimates of the plots: a volunteer (expert) diameter sampling error of 2.3 mm (1.4 mm) translated into 1.7% (0.9%) change in the biomass estimates calculated from species-specific allometric equations based upon diameter. Height sampling error had a dependent relationship with tree height. Including height measurements in biomass calculations compounded the sampling error markedly; the impact of volunteer sampling error on biomass estimates was 615%, and the expert range was 69%. Using dendrometer bands, used to measure growth rates, we calculated that the volunteer (vs. expert) sampling error was 0.6 mm (vs. 0.3 mm), which is equivalent to a difference in carbon storage of ±0.011 kg C/yr (vs. ±0.002 kg C/yr) per stem. Using a citizen science model for monitoring carbon stocks not only has benefits in educating and engaging the public in science, but as demonstrated here, can also provide accurate estimates of biomass or forest carbon stocks

Assessing carbon stocks using indigenous peoples' field measurements in Amazonian Guyana

Accurate estimations of carbon stocks across large tracts of tropical forests are key for participation in programs promoting avoided deforestation and carbon sequestration, such as the UN REDD+ framework. Trained local technicians can provide such data, and this, combined with satellite imagery, allows robust carbon stock estimation across vegetation classes and large areas. In the first comprehensive survey in Guyana conducted by indigenous people, ground data from 21 study sites in the Rupununi region were used to estimate above ground tree carbon density across a diversity of ecosystems and land use types. Carbon stocks varied between village sites from 1Tg to 22.7Tg, and these amounts were related to stem density and diameter. This variation was correlated with vegetation type across the region, with savannas holding on average 14MgCha-1 and forests 153MgCha-1. The results indicated that previous estimates based on remotely sensed data for this area may be inaccurate (under estimations). There were also differences in carbon densities between village sites and uninhabited control areas, which are presumably driven by community use. Recruiting local technicians for field work allowed (a) large amounts of ground data to be collected for a wide region otherwise hard to access, and (b) ensured that local people were directly involved in Guyana's Low Carbon Development Strategy as part of REDD+. This is the first such comprehensive survey of carbon stocks, carbon density and vegetation types over a large area in Guyana, one of the first countries to develop such a program. The potential inclusion of forests held by indigenous peoples in REDD+ programs is a global issue: we clearly show that indigenous people are capable of assessing and monitoring carbon on their lands

Conservation leadership must account for cultural differences

Effective leaders are critical in determining successful outcomes of conservation programs. As the business and economic leadership literature shows, awareness around cultural differences in leadership attributes is important for positive project outcomes set in inter-cultural contexts. We conducted a systematic review of the literature to understand whether, and how, the influence of cultural context was acknowledged when describing successful leadership attributes of conservation leadership. We found fifteen papers from different geographical regions (Africa, Asia, Europe, North America and South America) explicitly addressing conservation leadership attributes. We further explored how characteristics of four key attributes (i.e. motivating others, establishing a shared vision, effective communication and partnership building) were addressed within these different cultural settings. Our review shows that the discourse on how culture influences attributes of a conservation leader and its implications for conservation outcomes is very limited. Awareness and sensitivity around this influence is important as cultural differences may either facilitate or hinder conservation project outcomes, particularly when people from different cultural backgrounds work together

Edge effects on components of diversity and above-ground biomass in a tropical rainforest

Edge effects are among the most significant consequences of forest fragmentation. Therefore, understanding the impacts of edge creation on biodiversity is crucial for forest management and biological conservation. In this study, we used trait‐based and phylogenetic approaches to examine the effects of fragmentation on components of diversity and above‐ground biomass of rainforest tree communities in Madagascar in forest edge vs. interior habitats. Tree communities in forest edges showed lower phylogenetic diversity relative to those in interior habitats, suggesting that some clades may be more vulnerable to environmental filtering than others. Functional diversity was also significantly lower on the edge for productivity traits, but not for dispersal traits. Tree communities in the forest edge showed higher divergence of dispersal traits and lower divergence in productivity traits than expected, while functional diversity in interior forest did not differ from random expectations. This suggests that separate mechanisms affect productivity traits vs. dispersal traits in edge habitats. There was no significant difference in above‐ground biomass between edge and interior habitats, suggesting that edge effects have not yet negatively influenced the forest's potential for carbon storage. However, these changes may not have occurred yet, given the slow turnover of tree communities. Synthesis and applications. Our results highlight the role of edge effects in the erosion of functional and phylogenetic diversity of highly diverse tree communities. While above‐ground biomass did not appear to be affected by forest edge in our study, we suggest long‐term monitoring of forests for potential changes in ecosystem functioning. These findings also indicate the need to reduce edge creation and buffer existing edges for holistic biodiversity conservation

The threats endangering Australia's at-risk fauna

Reducing the rate of species extinctions is one of the great challenges of our time. Understanding patterns in the distribution and frequency of both threatened species and the threatening processes affecting them improves our ability to mitigate threats and prioritize management actions. In this quantitative synthesis of processes threatening Australian at-risk fauna, we find that species are impacted by a median of six threats (range 1–19), though there is considerable variation in numbers of threats among major taxonomic groups. Invasive species, habitat loss, biological resource use, natural systems modification and climate change are the processes most commonly affecting Australian threatened species. We identified an uneven distribution of research knowledge among species, with half of the total number of species-specific peer-reviewed scientific publications associated with only 11 threatened species (2.7%). Furthermore, the number of threats associated with each species was correlated with the research effort for that species, and research effort was correlated with body mass. Hence, there appears to be a research bias towards larger-bodied species, and certain charismatic species, that could result in inferences biased towards these favored species. However, after accounting for these effects we found that for birds, amphibians, reptiles and marine mammals body mass is positively correlated with the number of threats associated with each species. Many threats also co-occur, indicating that threat syndromes may be common

Norwalk Virus–specific Binding to Oyster Digestive Tissues

Specific binding of virus to oysters can selectively concentrate a human pathogen