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Showing posts with label wetlands. Show all posts
Showing posts with label wetlands. Show all posts

Saturday, October 27, 2018

A focus on fossil fuel emissions reduction as the primary solution to reversing climate change will continue to be ineffective

Replacing snow covered land with trees that absorb more sunlight in northern countries can actually accelerate warming regionally, creating a positive feedback loop that leads to further loss of highly-reflective snow and ice.

Climate researchers often suggest that the greatest potential for carbon sequestration in forests lies in the tropics; avoided deforestation, forest restoration and afforestation in these regions can play a significant role in mitigating global climate change.

Grassland biomes constitute approximately 40% of the global land surface area and possess massive potential for sequestering carbon in arid and semi-arid areas of the world. Healthy grasslands provide habitat for a biologically diverse range of plant and animal species, and also serve as a large reserve for soil carbon. Grasslands that sustain abundant stores of SOC have higher rates of water infiltration and retention and are less susceptible to environmental degradation such as soil erosion and drought. Although grasslands are currently facing desertification around the globe, proper land management can restore vegetation cover to protect soils from erosion and enhance the carbon sequestration capacity of these vital ecosystems.

While forests and dryland ecosystems contain the most soil carbon globally, the carbon density of wetland ecosystems is three and six times that of forests and grasslands/shrublands, respectively. The deep organic-rich soils of coastal wetlands contain carbon reserves that have been sequestered over millennia. These tidal ecosystems are able to store large quantities of carbon for two primary reasons: high-nutrient conditions that promote the rapid growth of carbon-sequestering plant biomass, and anaerobic soils that suppress microbial decomposition in the water-logged environment, allowing for long-term carbon storage. Tidal saline wetland ecosystems, including salt marshes and mangrove swamps, exhibit remarkable rates of below ground biomass production and enormous capacity as carbon sinks.

Conclusion : A focus on fossil fuel emissions reduction as the primary solution to reversing climate change will continue to be ineffective. Arbitrary goals to reduce emissions by 10, 30, 50 or even 80 percent are not going to prevent future warming. Basic scientific principles dictate that atmospheric CO2 concentrations will not decline without a significant rise in the carbon sequestration mechanisms of the biosphere. The good news is that there is enormous carbon sequestering potential in multiple ecological systems around the globe. The only question now is whether we will work to enhance the carbon storage capacities of nature or effectively continue to weaken them.


Acknowledgement : Text sourced entirely from this link.

Sunday, April 22, 2018

Birds & Ecosystem Services

Attribution: Andrew Butko / CC-BY-SA 3.0
Everyone in the world depends completely on Earth’s ecosystems and the services they provide, such as food, water, disease management, climate regulation, spiritual fulfillment, and aesthetic enjoyment. 

Studies have sought to examine the services provided by birds in the ecosystems they inhabit.

Birds encourage more and healthier plant growth by the spread of their poop which is an excellent additive to any fertilizer. By spreading activities through different habitats, birds can move nutrients from one place to another, which is particularly relevant in places where plant growth is limited by nutrient availability. A study on the islands in the Gulf of California showed that when birds roosted on them, the guano deposits they left behind provided nutrients to plants on the island. As a result, islands with seabirds had plants that grew taller and faster and were much more productive than those on islands without birds.

Utkarsh22december / CC-BY-SA 4.0
Wetlands are considered one of the most valuable habitats, providing an array of important services like shoreline stabilization and water filtration. In the southeastern United States, snails can overgraze the grasses in salt marshes and completely convert a productive marsh into mudflats. Several species of birds such as oystercatchers, curlews, and plovers are predators of these snails and control their numbers, which regulates primary productivity of salt marshes.

Waterbirds play key functional roles in many aquatic ecosystems, including as predators, herbivores and vectors of seeds, invertebrates and nutrients. Waterbirds can maintain the diversity of other organisms, control pests, be effective bio-indicators of ecological conditions, and act as sentinels of potential disease outbreaks. They also provide important provisioning (meat, feathers, eggs, etc.) and cultural services to both indigenous and westernized societies. 

Apple Blossom @ Manali, India / Sanu N / CC-BY-SA 4.0
The construction of nest boxes for great tits in apple orchards has been shown to lead to greater numbers of birds in the area, which forage on caterpillars that can cause damage to crops, resulting in significantly higher crop yields. Similarly, the use of artificial perches for raptors around agricultural fields may increase the number of raptors that prey on rodents that can cause damage to crops. If installed and maintained properly, the construction of bird nest boxes can eliminate the need for pesticides, saving farmers money and preventing potentially dangerous chemicals from being applied.

Buffalos and crane birds, Chinawal village, India / ABHIJEET / CC-BY-SA 3.0
Many birds perch on livestock like cattle and forage on insects that live on them. Cattle egrets are particularly well known for making a living this way. When infested with ticks, cows can become anemic and milk production flags. In Pakistan, birds are capable of effectively preying on these parasites, leading to healthier and more productive cows. This predation by birds is even more effective than pesticides in some cases.

Scavenging by birds is an important mechanism of waste disposal in many areas and prevents the outbreak of diseases than can occur through the accumulation of animal carcasses. In India, declines in vultures led to increases in feral dogs as there was less competition for carrion as a food source. The explosion of the dog population led to increases in rabies outbreaks and human injuries from dog attacks. The total estimated health cost of vulture declines between 1993 and 2006 is a whopping $34 billion.

KostasGiannakis / CC-BY-SA 4.0
Another way that birds can provide regulating services is through promoting forest growth. When birds pick a seed or fruit from a plant and fly off with it, they end up transporting the seed to another place where it can germinate. This behavior is a major mechanism for seed dispersal in many plants and can increase the genetic diversity of plants in a particular area by spreading seeds. By germinating the seeds of trees, birds can contribute to the reforesting of deforested lands, diminishing the costs of restoration. In oak forests in Sweden, the cost of replacing the seed dispersal services of Eurasian jays in oak regeneration is an estimated $9,400 per hectare
Finally, cultural services by birds include spiritual enrichment, companionship, music and the appreciation of nature.

Acknowledgement : The blog post above is largely an edited version of this article.