Tree plantations and forest restoration are leading strategies for enhancing terrestrial carbon (C) sequestration and mitigating climate change. While it is well established that species-rich natural ...forests offer superior C sequestering benefits relative to short-rotation commercial monoculture plantations, differences in rates of C capture and storage between longer-lived plantations (commercial or non-commercial) and natural forests remain unclear. Using a natural experiment in the Western Ghats of India, where late-20th century conservation laws prohibited timber extraction from monodominant plantations and natural forests within nature reserves, we assessed forests and plantations for aboveground C storage and the magnitude and temporal stability of rates of photosynthetic C capture (gross primary production). Specifically, we tested the hypothesis that species-rich forests show greater temporal stability of C capture, and are more resistant to drought, than monodominant plantations. Carbon stocks in monodominant teak (Tectona grandis) and Eucalyptus (Eucalyptus spp.) plantations were 30%-50% lower than in natural evergreen forests, but differed little from moist-deciduous forests. Plantations had 4%-9% higher average C capture rates (estimated using the Enhanced Vegetation Index-EVI) than natural forests during wet seasons, but up to 29% lower C capture during dry seasons across the 2000-18 period. In both seasons, the rate of C capture by plantations was less stable across years, and decreased more during drought years (i.e. lower resistance to drought), compared to forests. Thus, even as certain monodominant plantations could match natural forests for C capture and storage potential, plantations are unlikely to match the stability-and hence reliability-of C capture exhibited by forests, particularly in the face of increasing droughts and other climatic perturbations. Promoting natural forest regeneration and/or multi-species native tree plantations instead of plantation monocultures could therefore benefit climate change mitigation efforts, while offering valuable co-benefits for biodiversity conservation and other ecosystem services.
Conversion of tropical forests and diverse multicrop agricultural land to commercial monocultures is a conservation concern worldwide. In northeast India, landscapes under shifting agriculture (or ...jhum) practiced by tribal communities are increasingly being replaced by monoculture plantations (e.g., teak, oil palm). We compared oil palm and teak plantations, shifting agricultural fields, and forest fallows (0–8 yr regeneration) with tropical rainforest edge and interior sites in Dampa Tiger Reserve, Mizoram, India. Twenty replicate transects were surveyed in each of the 5 study strata for vegetation structure, bird species richness and density, bird abundance, and species composition. Tree density and canopy and vertical structure were lowest in oil palm plantations, intermediate in teak plantations and jhum, and highest in rainforest sites. Tree density in jhum (4.3 stems per 100 m2) was much higher than in oil palm plantations (0.5 stems per 100 m2), but lower than in rainforest (6.8–8.2 stems per 100 m2), with bamboo absent in oil palm plantations and most abundant in regenerating jhum (25 culms per 50 m2). We recorded 107 bird species (94 forest species, 13 open-country species). Oil palm plantations had the lowest forest bird species richness (10 species), followed by teak plantations (38), while jhum (50) had only slightly lower species richness than the rainforest edge (58) and interior (70). Forest bird abundance in the jhum landscape was similar to that in rainforest, on average 304% higher than in oil palm plantations, and 87% higher than in teak plantations. Jhum sites were more similar in bird community composition to rainforest than were monocultures. Rapid recovery of dense and diverse secondary bamboo forests during fallow periods makes the shifting agricultural landscape mosaic a better form of land use for bird conservation than monocultures. Land use policy and conservation plans should provide greater support for shifting agriculture, while mandating better land use practices such as retention of forest remnants, native trees, and riparian vegetation in monoculture plantations.
Forest fragmentation and habitat loss are major disruptors of plant–frugivore interactions, affecting seed dispersal and altering recruitment patterns of the dependent tree species. In a ...heterogeneous production landscape (primarily tea and coffee plantations) in the southern Western Ghats, India, we examined effects of surrounding forest cover and fruit crop size on frugivory of four rainforest bird‐dispersed tree species (N = 131 trees, ≥30 trees per species, observed for 623 hr). Frugivore composition differed among the four tree species with the large‐seeded Canarium strictum and Myristica dactyloides being exclusively dependent on large‐bodied avian frugivores, whereas medium‐seeded Persea macrantha and Heynea trijuga were predominantly visited by small‐bodied and large‐bodied avian frugivores, respectively. Using the seed‐dispersal‐effectiveness framework, we identified effective frugivores and examined their responses to forest cover and fruit crop size. Results were idiosyncratic and were governed by plant and frugivore traits. Visitations to medium‐seeded Persea had a positive relationship with forest cover but the relationship was negative for the large‐seeded Myristica. In addition, two of the three effective frugivores for Persea responded to the interactive effect of forest cover and fruit crop size. Frugivore visitations to Heynea were not related to forest cover or fruit crop, and there were too few visitations to Canarium to discern any trends. These results highlight the context‐specific responses of plant–frugivore interactions to forest cover and fruit crop size influenced by plant and frugivore traits.
Abstract
The prevalence of diverticular disease in the Western and industrialized nations has increased over the last century, and our understanding of this disease and its management continues to ...evolve. In this article, we review the literature regarding the postoperative quality of life (QOL) and functional outcomes following surgical management of diverticulitis, including information regarding bowel function, recurrence of symptoms, and other postoperative sequelae. While objective parameters, such as attacks of diverticulitis, complications, and clinical episodes have been studied, there is a paucity of data on less objective factors, such as overall patient satisfaction after operative management of diverticular disease. The literature shows improvement in QOL following surgical intervention for diverticulitis if preoperative QOL was significantly low, secondary to severe/complicated diverticulitis. However, a subset of patients does continue to have symptoms following surgical intervention for diverticulitis. Often neglected in the literature, there remains a need for prospective data evaluating preoperative function to ascertain the impact of surgery on patients' QOL and postoperative function.
Hypospadias is a common congenital abnormality typified by a proximally placed ectopic urethral meatus along the ventral surface of the penis. Androgen receptor (AR) and estrogen receptor (ER) ...expression in the hypospadias tissues may be altered in hypospadias.
We evaluated by immunohistochemistry the AR and ER expression in 75 tissues from hypospadias repair, and compared this expression to that of tissue from 75 patients undergoing circumcision. We also compared the intensity of AR and ER expression between different severities of hypospadias.
AR quantitative grading score decreased with severity of hypospadias, while the ER score increased as the hypospadias worsened, which was statistically significant (p-value <0.05).
The penile tissue AR expression is decreased and ER expression is increased with increasing severity of hypospadias.
Shows how Renaissance writers and artists struggled to reconcile past traditions with experiences of 'discovery'
In what ways have colonial and postcolonial studies transformed our perceptions of ...early modern European texts and images? How have those perceptions enriched our broader understanding of the colonial and the postcolonial? Focusing on English, Portuguese, Spanish and French colonial projects, Shankar Raman explains how encounters with new worlds and peoples irrevocably shaped both Europeans and their 'others'. There are in-depth case studies on: the Portuguese drama and epic of Gil Vicente and Luis Vaz de Camões; travel narratives and exotic engravings from Theodore de Bry's influential compilations; and the English plays and verse of Christopher Marlowe, John Donne and Richard Brome.
Key Features
Introduces readers to the careful reading of visual sources as a complement to textual analysisEmphasises the importance of comparative work in literary studies of colonialism: see especially the discussion of Adam Olearius' travels in Chapter 2 as well as the case studies of Portuguese literary texts and de Bry
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