RESUMO
Soil organisms are a crucial part of the terrestrial biosphere and are essential for ecosystem functioning. A major part of soil and sediment ecosystems are nematodes worms, which can be used as a bioindicator of soil status. These worms represent one of the most numerous animal phyla on earth, filling all trophic levels in the soil food web. Overall nematode abundance is related to net ecosystem productivity, and regional variations in abundance provides insight into local patterns of soil fertility and functioning. Methods for extracting nematodes from soils have been established, but these can be cumbersome, or require specialist equipment or consumables, meaning they are not always suitable for the field or remote areas. We have built on previous methods to develop a simple, more compact, and zero-waste method of extracting nematodes, using basic equipment. We demonstrate this in a small collection of soils from deforested, native forest, and reforested sites. On a larger scale, this method can be used to reflect overall ecosystem function, indicating current soil status, and future success and proliferation of reforested sites.
RESUMO
Zoonotic pathogens and parasites that are transmitted from vertebrates to humans are a major public health risk with high associated global economic costs. The spread of these pathogens and risk of transmission accelerate with recent anthropogenic land-use changes (LUC) such as deforestation, urbanisation, and agricultural intensification, factors that are expected to increase in the future due to human population expansion and increasing demand for resources.We systematically review the literature on anthropogenic LUC and zoonotic diseases, highlighting the most prominent mammalian reservoirs and pathogens, and identifying avenues for future research.The majority of studies were global reviews that did not focus on specific taxa. South America and Asia were the most-studied regions, while the most-studied LUC was urbanisation. Livestock were studied more within the context of agricultural intensification, carnivores with urbanisation and helminths, bats with deforestation and viruses, and primates with habitat fragmentation and protozoa.Research into specific animal reservoirs has improved our understanding of how the spread of zoonotic diseases is affected by LUC. The behaviour of hosts can be altered when their habitats are changed, impacting the pathogens they carry and the probability of disease spreading to humans. Understanding this has enabled the identification of factors that alter the risk of emergence (such as virulence, pathogen diversity, and ease of transmission). Yet, many pathogens and impacts of LUC other than urbanisation have been understudied.Predicting how zoonotic diseases emerge and spread in response to anthropogenic LUC requires more empirical and data synthesis studies that link host ecology and responses with pathogen ecology and disease spread. The link between anthropogenic impacts on the natural environment and the recent COVID-19 pandemic highlights the urgent need to understand how anthropogenic LUC affects the risk of spillover to humans and spread of zoonotic diseases originating in mammals.
