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The World According to Pimm: A Scientist Audits the Earth
... In comparison with most temperate ecosystems, tropical forests are characterized by extraordinarily high but poorly inventoried insect diversity (perhaps 5-10 million species, with less than 1 million of them described), and by an absence of basic biological and ecological information for all but a handful of non-pest species (Godfray et al., 1999;Novotny et al., 2002). Rates of tropical forest habitat degradation and destruction are higher than in almost any other biome (Sala et al., 2000;Pimm, 2001). In combination, these facts signal that the potential loss of insect diversity in tropical forests through human actions in the coming decades is enormous. ...
These proceedings contain papers on insect conservation biology that are classified under 3 themes: (1) the current status of insect conservation, and major avenues for progress and hindrances (6 papers); (2) insects as model organisms in conservation biology (6 papers); and (3) future directions in insect conservation biology (6 papers).
... Rates of subtropical and tropical forest habitat degradation and deforestation are higher than in almost any other biome (Sala et al. 2000;Pimm 2001). In China, old-growth forest areas typically found in remote or mountainous regions where the human population density is lower and accessibility of timber is complicated due to the difficult terrain. ...
Chinese species of Macrotomoderus Pic, 1901 are reviewed. Descriptions and
illustrations of seventeen new species from southern and eastern China are given, namely
M. bukejsi sp. nov., M. chingpo sp. nov., M. conus sp. nov., M. darrenmanni sp. nov.,
M. gracilis sp. nov., M. kawa sp. nov., M. makarovi sp. nov., M. microscopicus sp.
nov., M. mirabilis sp. nov., M. monstratus sp. nov., M. monstrificabilis sp. nov.,
M. perforatus sp. nov., M. periclitatus sp. nov., M. schuelkei sp. nov., M. silvicolus sp.
nov., M. spurisi sp. nov., and M. wuliangshan sp. nov. An updated identification key to
the Macrotomoderus of mainland China and Taiwan and annotated species list are
presented. Ecology and conservation status are briefly discussed.
... Biodiversity hotspots which are the most species-rich regions on Earth are declining rapidly. Tropical forests once covered about 14% of the Earth [20]. Today they occupy less than half of the original area. ...
... En el caso de Canadá la pesca de bacalao había llegado a 800 000 toneladas en 1968. Una subsecuente disminución llevó a fijar una cuota de 300 000 en 1988, pero en 1991 sólo se pudieron pescar 185 000 (Pimm, 2001). ...
En este trabajo se presentan datos de varios países sobre la importancia de los productos pesqueros en la alimentación mundial. Se hace una reseña del aumento de la actividad pesquera desde comienzos del siglo XX, en la que se incluye la expansión de las flotas, el aumento de su autonomía y el de las capturas. A partir aproximadamente de la década de 1960 muchas áreas son sobreexplotadas; lo cual conlleva un descenso en la captura de valiosas especies. Asimismo, se describen los efectos de la eutroficación y la contaminación, particularmente en casos cuyos resultados son catastróficos, tales como el de la anchoveta peruana, la desaparición de los recursos pesqueros en el mar de Aral, y la de disminución en la costa noreste de Estados Unidos y el delta del río Mississipi. Se mencionan también algunos convenios internacionales para limitar la explotación de determinadas áreas y conflictos por el derecho de pesca. En varios casos los mayores esfuerzos de pesca han tenido como resultado capturas decrecientes. El caso de Chile aparece como paradigmático de un aumento rápido, pero no sostenible, de las capturas. La reciente investigación de Watson y Pauly acerca de la falsificación de las estadísticas chinas muestra que en la última década se ha producido una declinación de las capturas a nivel mundial.
... The human population is increasing; as of 2015, the world population exceeded 7 billion and is projected to exceed 9 billion by 2050 (United Nations 2014). Through sheer numbers alone, humanity is consuming an increasing fraction of the planet's land resources, and the largest part of this is for food and fiber production (Pimm 2001). Industrialization is the second major driver of global change. ...
This chapter considers the possible effects of global change on the biodiversity of insects in agroecosystems and the implications of these effects for human society. The biodiversity of insects in agroecosystems is clearly important to both ecosystem sustainability and food production. Changes in the distribution and abundance of insect species driven by global change can lead to changes in community composition and diversity at local and regional scales, with implications for ecosystem processes. The chapter reviews these patterns and their underlying causes in the context of several important ecological processes in agroecosystems: predator‐prey interactions, soil maintenance, and crop pollination. For insects, changes in distribution and timing, declines in abundance, and outright extinctions are, and will continue to be, outcomes of ongoing global change processes. The best recommendations for conserving pollinator diversity in agriculture involve managing multiple risk factors as discussed in the chapter.
... We humans naturally select the richest environments as our home. Far beyond the 35-40% of global biological production we use ( Pimm 2001), our effects on biodiversity and natural beauty far exceed our growing impacts on raw physical factors in the environment such as temperature and freshwater. ...
This document proposes a Sonoran Desert Park in the Rio Nuevo downtown redevelopment and revitalization district. The proposed park site lies north of 22nd Street / Starr Pass Boulevard, astride the Santa Cruz River between Sentinel Peak and neighborhoods west of Interstate Highway 10. A large portion of the land contains a historic landfill that makes the site highly problematic for any more intensive use that would involve construction.
The primary benefits of the proposed natural open space park, in the downtown area, would include:
• Providing service to local, city-wide, and tourist constituencies with:
o A desert and desert-riparian experience
o Interpretation complementary to the Origin Park
o Varied recreational opportunities
• Park development options including:
o Natural areas for hiking and picnicking
o Biking/equestrian/bird-watching trails and/or connections
o More active youth recreational facilities.
• Key biodiversity connectivity for urban wildlife
Potential benefits of a natural park at the site are increased by association with adjoining and nearby natural, cultural, and recreational facilities and amenities:
• Tucson Origins Heritage Park including immediately adjacent restorations and re-creations of:
o Mission Gardens
o S’chuk Son Village
o Carillo House
o San August Mission
• Natural open spaces and trail systems:
o River Park and Urban Loop Trail system
o Sentinel Peak Park
o Santa Cruz River corridor, including:
o Santa Cruz River
o West Branch reserve
o Paseo de las Iglesias Phase 1
Park development at this site would significant enhance quality of life in the urban core of the city. It will contribute to tourism related to the revitalization of downtown Tucson.
There are major logistical constraints and challenges at the proposed site, which are described and explained in detail in the report:
• Existing large, inactive landfill waste underlying major parts of the available area:
o Restrictions on water use to avoid wetting the waste in the landfill and causing rapid decomposition and possible aquifer contamination
o High costs to remediate, remove, or re-contour the landfill
o Costs to provide proper soils for plants and human use of the surface
o Settling and methane production within the landfill, affecting any structures constructed in the landfill
o Utility lines within the waste
• Infrastructure needed for people to cross the river arroyo to access the entire park
• Linking the park with Sentinel Peak and Tucson Mountain Park requires traffic crossing provision for S Grande Avenue, which is the western margin of the proposed park area
This report contains detailed historical and current information on biodiversity, ecology, biodiversity connectivity, trail connectivity, historic land use, infrastructure, and logistic issues related to the proposed park property and nearby sites.
The document presents three conceptual design alternatives spanning a range of complexity, interest, difficulty, and logistical constraints and challenges:
• Alternative 1 – Desert Arroyo Park. This is the least costly alternative par design, with the least added soil and water and the least modification to the landfill. Desert plants like those that grew naturally on the landfill would be used, with added species using seed, plantings, and irrigation for initial plant establishment. However, with species diversity and vegetation structure lower than in other alternative designs, interest and aesthetic quality would also be less than in the other alternatives.
• Alternative 2 – Sonoran Desert Region Botanical Park. This alternative would reproduce the Sonoran Desert landscape (rock slope → gravelly upper bajada →loamy lower bajada → creosote flat → saltbush flat) and, optionally, include multiple smaller vignette gardens presenting diverse aspects of the vegetation and ecology of the Sonoran Desert region of the United States. Deeper, more precisely textured soils would be required, and contouring the landfill surface would likely be required, adding significant cost. Species diversity, shade, interest, and aesthetic value would be high.
• Alternative 3 – Bosque Park. This very rich, attractive, and shady alternative design would reproduce the original mesquite-dominated floodplain forest that drew people to Tucson originally. The water and soil requirements of this ecosystem would require nearly complete mitigation of the A Mountain landfill, which would be very costly. Species diversity would be similar to Alternative 2, but aesthetic value, shade, and interest would be significantly greater. Following landfill remediation, the bosque could be sustainable using runoff captured from Sentinel Peak.
Each alternative is presented with detailed information on appropriate plant species and vegetation structure, along with information on expected animal biodiversity and logistical constraints. Final designs are not presented here: some elements of the three alternatives might to some extent be combined in a final design for construction.
Elements common to all three design alternatives include:
• Interpretive vignettes with signage covering:
o Natural and cultural history
o Environmental history
o Urban biodiversity
o Riparian degradation and restoration
o Landfill issues
o Sustainability and alternative futures
• Trails and signage
• Picnic tables, benches, and barbeque grills
• Shade ramadas
• Access and comfort station facilities
• Pedestrian bridge(s) crossing the river (optional)
• Water feature (optional)
• Enhanced desert riparian planting along river paths and elsewhere away from the landfill waste
... In recent years, the human impact has become far more important than others (Pimm, 2001). Anthropogenic threats leading to extinction of species and consequent loss of biodiversity are: introduction of non-native species, iii) overexploitation, iv) soil, water and atmospheric pollution, and v) intensive agriculture and forestry, vi) climate change, vii) N-deposits and CO 2 loading of atmosphere. ...
Humans since ancient time are utilising the valuable natural resources. Biodiversity has several roles in functioning and sustaining the natural ecosystems besides providing various benefits to humans. Inappropriate and excessive consumption of natural resources and fossil fuels have negatively impacted our surrounding environment. One of the change include change in the climate. The climate change is a natural process occurring over large scale of time. However human activities have accelerated this climate change which now happens over relatively short period of time. The living organisms have optimum range of tolerance for their surrounding environment. So any change in climate cause change in their habit, abiotic relationships, biotic relationships as well as their niche and in worst case scenario it might result in its extinction. As the organisms have very intricate and complex relationship with its environment it’s difficult to predict the various impacts of climate on organism, species, population, community, ecosystem and biodiversity as whole. There is an urgent need to study the impacts of climate change at every level so as to propose models which will help in reducing these impacts in a sustainable way. In this short review, I would like to emphasise on the different role of biodiversity which will be impacted by climate change.
This paper, which addresses the issue of the extinction of mite species at the global scale for the first time, highlights mite diversity, assesses the evidence for an extinction process, discusses contributing factors and estimates losses. The ~1 250 000 mite species occupy an enormous variety of terrestrial and freshwater ecosystems from the equator to the polar regions and to high altitudes. Some groups provide essential ecosystem services, including the incorporation of organic matter into the soil. The maintenance of mite diversity is inextricably linked to the continuance of floristic diversity, habitat complexity and insect diversity. The majority of mite species are assumed to be in the tropical rainforests, of which >50% has been destroyed or severely degraded. Most biodiversity hotspots are in tropical forests; endemic phytoseiid mite species are at least 17 times more concentrated in the hotspots than outside. Habitat destruction and degradation continue on an enormous scale, with increasing human population growth and resource consumption the overarching drivers of extinction. Moreover, climate change is likely to be worsening the effects of the other drivers at an increasing rate. The small body of direct evidence and a considerable body of indirect evidence strongly suggest the continuing, widespread extinction of mite species. Based on estimates of overall biodiversity loss, ~15% of mite species were likely to have become extinct by 2000, with losses currently expected to increase by between 0.6% and 6.0% by 2060. More detailed information on both spatial differences in mite assemblages and anthropogenic threats worldwide is crucial because they underpin the total number of species and their vulnerability to extinction, respectively. The rapid expansion of the protected area estate to capture the maximum possible area of ecosystem heterogeneity, especially in the biodiversity hotspots, is essential, as is best practice management of these areas.
Biodiversity refers to the structural and functional variety of life at genetic, population, community, and ecosystem levels. Biodiversity is the core value of conservation biology, and preventing biodiversity loss is the discipline’s mission. Such loss is a systemic outcome of human use and occupancy of land and disruptions of ecological processes. Various systemic strategies of protection including direct legislation, regulation of trade in endangered species, and establishment of protected areas for endangered species have had significant but incomplete success. Protection-oriented approaches employ systematic prioritization of sites by treating site-specific threat of loss, ecological uniqueness, and opportunity for acquisition as primary determinants of priority. In contrast, management-oriented approaches emphasize maintenance of gene flow, creation of resources for habitat and niche specialization, and maintaining effective population sizes.
The first wave of human colonists spread across the Pacific from 4000 to 1000 years ago. That they caused many extinctions is well known from fossil finds. We estimate how many fossil species were missed - the answer is roughly half - and so estimate the true extinction rate. The first colonists exterminated roughly half the species on each island group. Some of these extinctions are falsely attributed to the first colonists, because intensive collection often began a half century after the damage initiated by European discovery. Even taken at face value, these recent extinctions are too few. Many species are so critically endangered that we know neither whether they still survive or how to save them. Interestingly, there are fewer recent extinctions and currently endangered species in the islands of the western Pacific, which were the islands occupied first by humans. We suggest that the species sensitive to human occupation died out long ago in these areas. If so, these islands would have lost even more than half of their bird species.
Late Pleistocene glaciations have been ascribed a dominant role in sculpting present-day diversity and distributions of North
American vertebrates. Molecular comparisons of recently diverged sister species now permit a test of this assertion. The Late
Pleistocene Origins model predicts a mitochondrial DNA divergence value of less than 0.5 percent for avian sister species
of Late Pleistocene origin. Instead, the average mitochondrial DNA sequence divergence for 35 such songbird species pairs
is 5.1 percent, which exceeds the predicted value by a factor of 10. Molecular data suggest a relatively protracted history
of speciation events among North American songbirds over the past 5 million years.
Extinctions of 3 genera, 27 species, and 13 subspecies of fishes from North America are documented during the past 100 years. Extinctions are recorded from all areas except northern Canada and Alaska. Regions suffering the greatest loss are the Great Lakes, Great Basin, Rio Grande, Valley of Mexico, and Parras Valley in Mexico. More than one factor contributed to the decline and extinction of 82% of the fishes. Physical habitat alteration was the most frequently cited causal factor (73%). Detrimental effects of introduced species also were cited in 68% of the extinctions. Chemical habitat alteration (including pollution) and hybridization each were cited in 38% of the extinctions, and overharvesting adversely affected 15% of the fishes. This unfortunate and unprecedented rate of loss of the fishery resource is expected to increase as more of the native fauna of North America becomes endangered or threatened.
In recent years, ecologists and economists have learned the importance
of working together. But the alliance has at times been rocky,
particularly as there is no consensus on how cooperation is most
effectively achieved.
Geographic patterns of species richness are influenced by many factors, but the role of shared physiographical and physiological boundaries in relation to range-size
distributions has been surprisingly neglected, in spite of the fact that such geometric
constraints lead to mid-domain richness peaks even without environmental
gradients (the mid-domain effect). Relying on null models, several recent studies
have begun to quantify this problem using simulated and empirical data. This
approach promises to transform how we perceive geographic variation in diversity,
including the long unresolved latitudinal gradient in species richness. The question is
not whether geometry affects such patterns, but by how much.