Applied nucleation, mostly based upon planting tree islands, has been proposed as a cost‐effective strategy to meet ambitious global forest and landscape restoration targets. We review results from a 15‐year study, replicated at 15 sites in southern Costa Rica, that compares applied nucleation to natural regeneration and mixed‐species tree plantations as strategies to restore tropical forest. We have collected data on planted tree survival and growth, woody vegetation recruitment and structure, seed rain, litterfall, epiphytes, birds, bats and leaf litter arthropods. Our results indicate that applied nucleation and plantation restoration strategies are similarly effective in enhancing the recovery of most floral and faunal groups, vegetation structure and ecosystem functions, as compared to natural regeneration. Seed dispersal and woody recruitment are higher in applied nucleation and plantation than natural regeneration treatments; canopy cover has increased substantially in both natural regeneration and applied nucleation treatments; and mortality of planted N‐fixing tree species has increased in recent years. These trends have led to rapid changes in vegetation composition and structure and nutrient cycling. The applied nucleation strategy is cheaper than mixed‐species tree plantations, but there may be social obstacles to implementing this technique in agricultural landscapes, such as perceptions that the land is not being used productively. Applied nucleation is likely to be most effective in cases where: planted vegetation nuclei enhance seed dispersal and seedling establishment of other species; the spread of nuclei is not strongly inhibited by abiotic or biotic factors; and the approach is compatible with restoration goals and landowner preferences.
Zoonotic diseases represent 75% of emerging infectious diseases worldwide, and their emergence is mainly attributed to human‐driven changes in landscapes. Land use change, especially the conversion of natural areas to agricultural use, has the potential to impact hosts and vector dynamics, affecting pathogen transmission risk. While these links are becoming better understood, very few studies have investigated the opposite question—how native vegetation restoration affects zoonotic disease outbreaks. We reviewed the existing evidence linking native vegetation restoration with zoonotic transmission risk, identified knowledge gaps, and, by focusing on tropical areas, proposed forest restoration strategies that could help in limiting the spread of zoonotic diseases. We identified a large gap in information on the effects of native vegetation restoration on zoonotic diseases, especially within tropical regions. In addition, the few studies that exist do not consider environmental aspects that can affect the outcomes of restoration on disease risk, such as the land use history and landscape structural characteristics (as composition and configuration of native habitats). Our conceptual framework raises two important points: (1) the effects of forest restoration may depend on the context of the existing landscape, especially the percentage of native vegetation existing at the beginning of the restoration; and (2) these effects will also be dependent on the spatial arrangement of the restored area within the existing landscape. Furthermore, we propose important topics to be studied in the coming years to integrate zoonotic disease risk as a criterion in restoration planning.
- Award ID(s):
- 2225023
- PAR ID:
- 10437563
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Applied Ecology
- Volume:
- 60
- Issue:
- 8
- ISSN:
- 0021-8901
- Page Range / eLocation ID:
- p. 1510-1521
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Synthesis and applications . Results from our 15‐year, multi‐site study show that applied nucleation can be a cost‐effective strategy for facilitating tropical forest regeneration that holds promise for helping to meet large‐scale international forest restoration commitments. -
Purpose of Review: In this paper, we synthesize the status and trends of studies assessing the effects of landscape structure and changes on zoonotic and vector-borne disease risk in the Tropical America region (i.e., spanning from Mexico to southern South America). Understanding how landscape structure affects disease emergence is critical to designing prevention measures and maintaining healthy ecosystems for both animals and humans. Recent Findings: We found that there is a small number of articles being published each year regarding landscape structure and zoonotic and vector borne diseases in the Tropical Americas region, with a slight growing trend after 2013. We identified a large knowledge gap on the subject in most of the countries: in 15 of 27 countries, no article was found, and 72% of the current literature available is concentrated in only three countries (Brazil, Panama, and Colombia). Five diseases represent about 68% of the available knowledge, which compared to over 200 types of known zoonoses and vector-borne diseases, is an extremely low number. Most of the knowledge that exists for the region is about landscape composition, with few studies evaluating configuration parameters. Summary: In general, landscape changes presented a positive effect on zoonotic and disease risk in most of the studies found, with habitat loss, fragmentation and increases in the amount of edge habitats leading to an increased risk of the diseases investigated. The continued integration of landscape ecology into disease ecology studies can increase the knowledge about how land use change is affecting animals and human health and can allow the establishment of guidelines to create landscapes that have a low pathogenicity.more » « less
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Abstract Rodents are key reservoirs of zoonotic pathogens and play an important role in disease transmission to humans. Importantly, anthropogenic land‐use change has been found to increase the abundance of rodents that thrive in human‐built environments (synanthropic rodents), particularly rodent reservoirs of zoonotic disease. Anthropogenic environments also affect the microbiome of synanthropic wildlife, influencing wildlife health and potentially introducing novel pathogens. Our objective was to examine the effect of agricultural development and synanthropic habitat on microbiome diversity and the prevalence of zoonotic bacterial pathogens in wild
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Abstract Thresholds in the relationship between species richness and natural land cover can inform landscape‐level vegetation protection and restoration targets. However, landscapes differ considerably in composition and other environmental attributes. If the effect of natural land cover on species richness depends on (i.e., interacts with) these attributes, and this affects the value of thresholds in this relationship, such dependencies must be considered when using thresholds to guide landscape management.
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Abstract Large terrestrial herbivorous mammals (LTH‐mammals) influence plant community structure by affecting seedling establishment in mature tropical forests. Many of these LTH‐mammals frequent secondary forests, but their effects on seedling establishment in them are understudied, hindering our understanding of how LTH‐mammals influence forest regeneration in human‐modified landscapes.
We tested the hypothesis that the strength of LTH‐mammals' effects on seedling establishment depends on landscape protection, forest successional stage and plant species' traits using a manipulative field experiment in six 1‐ha sites with varying successional age and landscape protection. In each site, we established 40 seedling plot‐pairs, with one plot excluding LTH‐mammals and one not, and monitored seedlings of 116 woody species for 26 months.
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Synthesis and applications. Insight into the interactions between LTH‐mammals and seedling communities in forest regeneration can be instrumental in planning effective restoration efforts. We highlight the importance of landscape protection in seedling survival and the role of LTH‐mammals in promoting seedling diversity in mature forests but also in secondary successional forests. The findings suggest that conservation efforts and possibly trophic rewilding can be important approaches for preserving diversity and influencing the trajectory of secondary tropical forest succession. However, we also caution that an overabundance of LTH‐mammals may adversely impact the pace of forest succession due to their preference for large‐seeded species. Therefore, a comprehensive wildlife management plan is indispensable. Additionally, longer term studies on LTH‐mammals are necessary to understand the effects of temporal fluctuations that are undetected in short‐term studies.
