Arrested succession in pastures hinders regeneration of Tropandean forests and shreds mountain landscapes

Arrested succession is conspicuous in the abandoned pastures of the Andean piedmont that have encroached upon the tropical montane forests toward higher limits and steeper slopes. Habitat 'shredding' is analysed to depict the current spatial configuration of tropical Andean landscapes, based on fragmentation patterns prompted by seed dispersal ecology and pasture encroachment.Seed dispersal was studied to address the hypo-thesis that seed input constrains the recruitment of montane forest seedlings, thus impeding pasture conversion to forest. It turns out that a better competitor, the tussock grass Setaria sphacelata, is limiting dispersal success due to its bioarchitecture and planting patterns. Because of the variegation of fragments, the area is in danger of landscape homogeneity within a matrix of degraded pasture. Currently, protection of fragmented remnants and restoration of original landscape structure and function are urgent needs for land-use planning toward sustainable development in the region.Restoration ecology is plausible as a means of conservation for degraded Tropandean forests, since human impacts have shredded landscapes entirely. Dispersal ecology may be used to facilitate pasture conversion to forest in equatorial landscapes, but the proactive approach of pasture removal or planting strategy should differ from that for lowland Amazonia, where abandoned pastures are different from those of montane environs. However, the region may be proactively managed only if political decisions include conservation as a goal of development.

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Quantitative polymorphism of tandem repeats as a method of epigenetic regulation of the of human cells response to oxidative stress

Nauchno-prakticheskii zhurnal «Medicinskaia genetika» ◽

10.25557/2073-7998.2020.12.68-70 ◽

2020 ◽

pp. 68-70

Author(s):

Н.Н. Вейко ◽

Е.С. Ершова ◽

М.С. Конькова ◽

Е.М. Малиновская ◽

С.В. Костюк

Keyword(s):

Adaptive Response ◽

Spatial Organization ◽

Tandem Repeats ◽

Spatial Configuration ◽

Human Cells ◽

Central Regions ◽

Schizophrenic Patients ◽

Response To Stress ◽

Cell Genome ◽

And Function

Пространственная организация хроматина важна для нормального функционирования клетки. На архитектуру ядра влияют размеры отдельных фрагментов генома, которые коррелируют с числом копий этих фрагментов. Перемещение локусов 1q12 от поверхности ядра в центральные области является ключевой стадией адаптивного ответа клетки на стресс. Мы предположили, что размер локусов 1q12, который коррелирует с содержанием повтора f-SatIII, может влиять на перемещение этих участков хроматина в ядре. Методом FISH на выделенных лимфоцитах показали, что в контроле локусы 1q12 расположены вблизи поверхности ядра, в ядрах лимфоцитов больных шизофренией (БШ) и облученных контрольных клеток локусы 1q12 расположены в центральных районах ядра. Длительное культивирование облученных лимфоцитов сопровождалось гибелью клеток, и снижением содержания f-SatIII в ДНК. Очевидно, что погибали клетки с большим размером 1q12 (много f-SatIII), обогащая популяцию клетками с низким содержанием f-SatIII. В клетках БШ и в облученных клетках мы обнаружили повышение уровня РНК SATIII. Размеры гетерохроматина 1q12 в клетках человека могут влиять на процессы пролиферации и ответа клетки на стресс. Количественный полиморфизм тандемных повторов генома - один из эпигенетических механизмов регуляции ответа клеток на окислительный стресс. The spatial organization of chromatin is important for the normal functioning of the cell. Genome repeat cluster sizes can affect the chromatin spatial configuration and function. The 1q12 heterochromatin loci movement from the periphery to the center of the nucleus is the cells’ universal response to various types of stress. We hypothesized that a large 1q12 domain could affect chromatin movement, thereby inhibiting adaptive response (AR). Using the FISH method, we shown that in the control, 1q12 loci are located near the surface of the nucleus; in the lymphocyte nuclei of schizophrenic patients and irradiated control cells, 1q12 loci are located in the central regions of the nucleus. During prolonged cultivation, the irradiated cells with a large Large f-SatIII amount die and the population is enriched with the cells with low f-SatIII content. In intact SZ patients’ lymphocytes and in irradiated cells we found an increase in SATIII RNA levels. The size of heterochromatin 1q12 loci in human cells can affect to the proliferation and cells’ adaptive response to stress. Quantitative polymorphism of tandem genome repeats is one of the epigenetic mechanisms of genome expression’s regulation.

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Restoration of pollination interactions in communities invaded by non-native plants.

Plant invasions: the role of biotic interactions ◽

10.1079/9781789242171.0021 ◽

2020 ◽

pp. 377-390

Author(s):

Christopher N. Kaiser-Bunbury ◽

◽

Benno I. Simmons ◽

◽

Keyword(s):

Plant Species ◽

Restoration Ecology ◽

Invasive Plant ◽

Ecosystem Processes ◽

Community Level ◽

Ecological Communities ◽

Management Interventions ◽

And Function ◽

Network Metrics ◽

The Impact

Invasive plant species degrade and homogenize ecosystems worldwide, thereby altering ecosystem processes and function. To mitigate and reverse the impact of invasive plants on pollination, a key ecosystem function, conservation scientists and practitioners restore ecological communities and study the impact of such management interventions on plant-pollinator communities. Here, we describe opportunities and challenges associated with restoring pollination interactions as part of a holistic ecosystem-based restoration approach. We introduce a few general concepts in restoration ecology, and outline best planning and evaluation practices of restoring pollination interactions on the community level. Planning involves the selection of suitable plant species to support diverse pollinator communities, which includes considerations of the benefits and disadvantages of using native vs exotic, and bridge and framework plant species for restoration. We emphasize the central role of scientific- and community-level approaches for the planning phase of pollination restoration. For evaluation purposes, we argue that appropriate network indicators have the advantage of detecting changes in species behaviour with consequences for ecosystem processes and functions before these changes show up in altered species communities. Suitable network metrics may include interaction diversity and evenness, and network measures that describe the distribution of species, such as network and species-level specialization, modularity and motifs. Finally, we discuss the usefulness of the network approach in evaluating the benefits of restoration interventions for pollination interactions, and propose that applied network ecologists take a central role in transferring theory into practice.

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Human impacts on hydrology in the Pantanal wetland of South America

Water Science & Technology ◽

10.2166/wst.2002.0377 ◽

2002 ◽

Vol 45 (11) ◽

pp. 35-44 ◽

Cited By ~ 17

Author(s):

S.K. Hamilton

Keyword(s):

South America ◽

Human Activities ◽

Human Impacts ◽

Structure And Function ◽

Natural State ◽

Ecological Structure ◽

The Past ◽

Influences Of Human Activities ◽

And Function ◽

Pantanal Wetland

Inundation patterns in the Pantanal remain in a relatively natural state, yet a number of significant human influences have occurred in the past, and there is potential for more severe human impacts as development of the region continues in the future. The objectives of this paper are 1) to briefly review the linkages between hydrology and ecological structure and function in the Pantanal; 2) to review some documented cases of historical influences of human activities on hydrology in the region; and 3) to consider potential future impacts, particularly in regard to the recently proposed navigation project known as the Paraguay-Paraná Waterway (or Hidrovía).

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Chromatin Spatial Configuration and Function in Metazoans

10.3389/978-2-88971-431-5 ◽

2021 ◽

Keyword(s):

Spatial Configuration ◽

And Function

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Human Impact in the Midriff Islands

Island Biogeography in the Sea of Cortés II ◽

10.1093/oso/9780195133462.003.0021 ◽

2002 ◽

Author(s):

Conrad J. Bahre ◽

Luis Bourillón

Keyword(s):

Land Use Planning ◽

Human Impacts ◽

Late Nineteenth Century ◽

Marine Biota ◽

San Lorenzo ◽

European Contact ◽

San Pedro ◽

Maximum Elevation ◽

Desert Island ◽

Northwestern Mexico

Although many students of island biogeography consider the midriff islands one of the world’s last major refuges of pristine desert-island biota, humans have been a part of that ecosystem for possibly 10,000 years or more. Humans have long affected the terrestrial and inshore marine biota, but the most serious injuries they have caused apparently began in the mid- to late nineteenth century with the start of guano mining on Patos, Rasa, and San Pedro Mártir islands. Since then, most of the major human impacts affecting the Midriff are related to rapid population growth in northwestern Mexico and increasing demands for the Midriff’s fishery and tourist resources. This chapter offers both historical and ecological perspectives on the human occupancy of the Midriff, so that a cultural-historical foundation will be available for ecological studies in the region as well as for land-use planning and conservation. The Midriff, located between 28° and 29°45´N and 112° and 114°W, includes the coasts of Lower California and Sonora and 39 islands and islets. Tiburόn, with an area of 1223.53 km2 and a maximum elevation of 1219 m, and Ángel de la Guarda, with an area of 936.04 km2 and a maximum elevation of 1315 m, are among the largest and most mountainous islands of Mexico. The other major islands of the Midriff, in order of decreasing size, are San Esteban (40.72 km2), San Lorenzo (33.03 km2), Smith (Coronado) (9.13 km2), San Lorenzo Norte (Las Ánimas) (4.26 km2), San Pedro Mártir (2.9 km2), Mejía (2.26 km2), Partida Norte (1.36 km2), Dátil (Turner) (1.25 km2), Alcatraz (Tassne or Pelícano) (1.2 km2), Salsipuedes (1.16 km2), Estanque (Pond) (1.03 km2), Rasa (0.68 km2), and Patos (0.45 km2) (Murphy, unpublished data). The entire region is extremely arid, and Tiburón is the only island that has permanent potable water, found in a few springs or in tinajas, although several tinajas on Ángel de la Guarda may contain water for long periods. The only island permanently inhabited since initial European contact is Tiburón, the historic stronghold of the Seri Indians or Comcáac, once a seminomadic, nonagricultural, seafaring, hunting, fishing, and gathering people.

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673 Resistance and Resilience of Native Forests to Disturbance by Hurricane Iniki

HortScience ◽

10.21273/hortsci.34.3.564c ◽

1999 ◽

Vol 34 (3) ◽

pp. 564C-564

Author(s):

James H. Fownes ◽

Robin A. Harrington ◽

Darrell A. Herbert

Keyword(s):

Land Use Planning ◽

Relative Rate ◽

Agroforestry Systems ◽

Forest Damage ◽

Native Forest ◽

Ecosystem Structure ◽

Metrosideros Polymorpha ◽

Perennial Crop ◽

And Function ◽

Ecosystem Structure And Function

Two studies were established in upland native forest of northwestern Kauai before Hurricane Iniki (Sept. 1992). One study was a gradient study in Acacia koa forest in the leeward rain shadow and the second study was a replicated fertilization experiment in mesic Metrosideros polymorpha forest. Both studies escaped devastation by high-intensity microbursts. Removal of LAI (from 3% to 80%) was proportional to pre-hurricane LAI, suggesting that resistance to damage was higher in low LAI, low-productivity sites. LAI recovered to prehurricane levels within 2 years, except in plots with major limb and stem loss. In the Acacia forest, damage to overstory trees was less than to understory trees, whereas in Metrosideros forest, larger trees were more damaged than smaller trees. During 2 years of recovery, both forests lost LAI in winter storms nearly equivalent to the hurricane damage. Disturbance is more frequent than previously known, which suggests that chronic disturbance needs to be better understood as a force regulating ecosystem structure and function. In both studies, the relative rate of recovery was faster in the more productive but more disturbed plots, suggesting that ecosystem resistance and resilience were traded off. These results have application to land use planning, agroforestry systems management, and other perennial crop management decisions following damage by a tropical cyclone.

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Editorial: Chromatin Spatial Configuration and Function in Metazoans

Frontiers in Genetics ◽

10.3389/fgene.2021.734981 ◽

2021 ◽

Vol 12 ◽

Author(s):

Paul Delgado-Olguín ◽

Katarzyna Oktaba ◽

Mayra Furlan-Magaril

Keyword(s):

Spatial Configuration ◽

And Function

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History Hidden in the Landscape

People and the Land through Time ◽

10.12987/yale/9780300225808.003.0001 ◽

2019 ◽

pp. 3-17

Author(s):

Emily W. B. Russell Southgate

Keyword(s):

Historical Ecology ◽

Human Impacts ◽

Historical Research ◽

Historical Factors ◽

System P ◽

The World ◽

History Of ◽

Patterns And Processes ◽

And Function ◽

System Today

Using a wide variety of examples, this chapter emphasizes evidence that all landscapes and ecosystems today reflect not only climate change but also intensive and extensive past human impacts. They cannot be interpreted solely based on conditions evident today. The imprints of past human activities which can be obvious or subtle, must be unraveled for understanding the system today. Historical ecology integrates various drivers of change, and stability, using interdisciplinary methods, to provide a deeper understanding of structure and function today. Conservation seeks in some places to maintain ecosystems that have arisen over centuries or even millennia due to human impact, for example, ancient woodlands and upland meadows in Europe. In many parts of the world such ancient systems are reservoirs of high biodiversity. Historical research illuminates the historical factors that contribute to this diversity, assisting in planning for conservation. A major point is that ecologists are apt to make mistakes in interpreting patterns and processes as well as in conservation and restoration if they do not consider the history of sites, which provides evidence of past variability and of processes that have led to the current conditions of the system.

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Restoration of pollination interactions in communities invaded by non-native plants.

Plant invasions: the role of biotic interactions ◽

10.1079/9781789242171.0377 ◽

2020 ◽

pp. 377-390

Author(s):

Christopher N. Kaiser-Bunbury ◽

Benno I. Simmons

Keyword(s):

Plant Species ◽

Restoration Ecology ◽

Invasive Plant ◽

Ecosystem Processes ◽

Community Level ◽

Ecological Communities ◽

Management Interventions ◽

And Function ◽

Network Metrics ◽

The Impact

Abstract Invasive plant species degrade and homogenize ecosystems worldwide, thereby altering ecosystem processes and function. To mitigate and reverse the impact of invasive plants on pollination, a key ecosystem function, conservation scientists and practitioners restore ecological communities and study the impact of such management interventions on plant-pollinator communities. Here, we describe opportunities and challenges associated with restoring pollination interactions as part of a holistic ecosystem-based restoration approach. We introduce a few general concepts in restoration ecology, and outline best planning and evaluation practices of restoring pollination interactions on the community level. Planning involves the selection of suitable plant species to support diverse pollinator communities, which includes considerations of the benefits and disadvantages of using native vs exotic, and bridge and framework plant species for restoration. We emphasize the central role of scientific- and community-level approaches for the planning phase of pollination restoration. For evaluation purposes, we argue that appropriate network indicators have the advantage of detecting changes in species behaviour with consequences for ecosystem processes and functions before these changes show up in altered species communities. Suitable network metrics may include interaction diversity and evenness, and network measures that describe the distribution of species, such as network and species-level specialization, modularity and motifs. Finally, we discuss the usefulness of the network approach in evaluating the benefits of restoration interventions for pollination interactions, and propose that applied network ecologists take a central role in transferring theory into practice.

Download Full-text