Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature reserves. It can also be caused by immobile, travel restricted populations of native or non-native wild animals.
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, such as clover, and other herbs. Grasslands occur naturally on all continents except Antarctica and are found in most ecoregions of the Earth. Furthermore, grasslands are one of the largest biomes on Earth and dominate the landscape worldwide. There are different types of grasslands: natural grasslands, semi-natural grasslands, and agricultural grasslands. They cover 31–69% of the Earth's land area.
A savanna or savannah is a mixed woodland-grassland biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of grasses. Four savanna forms exist; savanna woodland where trees and shrubs form a light canopy, tree savanna with scattered trees and shrubs, shrub savanna with distributed shrubs, and grass savanna where trees and shrubs are mostly nonexistent.
A controlled or prescribed (Rx) burn is the practice of intentionally setting a fire to change the assemblage of vegetation and decaying material in a landscape. The purpose could be for forest management, ecological restoration, land clearing or wildfire fuel management. A controlled burn may also refer to the intentional burning of slash and fuels through burn piles. Controlled burns may also be referred to as hazard reduction burning, backfire, swailing or a burn-off. In industrialized countries, controlled burning regulations and permits are usually overseen by fire control authorities.
Worldwide more human beings gain their livelihood from agriculture than any other endeavor; the majority are self-employed subsistence farmers living in the tropics. While growing food for local consumption is the core of tropical agriculture, cash crops are also included in the definition.
African environmental problems are problems caused by the direct and indirect human impacts on the natural environment and affect humans and nearly all forms of life in Africa. Issues include deforestation, soil degradation, air pollution, water pollution, coastal erosion, garbage pollution, climate change, Oil spills, Biodiversity loss, and water scarcity. These issues result in environmental conflict and are connected to broader social struggles for democracy and sovereignty. The scarcity of climate adaptation techniques in Africa makes it the least resilient continent to climate change.
Environmental toxicology is a multidisciplinary field of science concerned with the study of the harmful effects of various chemical, biological and physical agents on living organisms. Ecotoxicology is a subdiscipline of environmental toxicology concerned with studying the harmful effects of toxicants at the population and ecosystem levels.
The extensive and rapid clearing of forests (deforestation) within the borders of Nigeria has significant impacts on both local and global scales.
Bushfires in Australia are a widespread and regular occurrence that have contributed significantly to shaping the nature of the continent over millions of years. Eastern Australia is one of the most fire-prone regions of the world, and its predominant eucalyptus forests have evolved to thrive on the phenomenon of bushfire. However, the fires can cause significant property damage and loss of both human and animal life. Bushfires have killed approximately 800 people in Australia since 1851, and billions of animals.
The environmental impact of agriculture is the effect that different farming practices have on the ecosystems around them, and how those effects can be traced back to those practices. The environmental impact of agriculture varies widely based on practices employed by farmers and by the scale of practice. Farming communities that try to reduce environmental impacts through modifying their practices will adopt sustainable agriculture practices. The negative impact of agriculture is an old issue that remains a concern even as experts design innovative means to reduce destruction and enhance eco-efficiency. Animal agriculture practices tend to be more environmentally destructive than agricultural practices focused on fruits, vegetables and other biomass. The emissions of ammonia from cattle waste continue to raise concerns over environmental pollution.
Agricultural pollution refers to biotic and abiotic byproducts of farming practices that result in contamination or degradation of the environment and surrounding ecosystems, and/or cause injury to humans and their economic interests. The pollution may come from a variety of sources, ranging from point source water pollution to more diffuse, landscape-level causes, also known as non-point source pollution and air pollution. Once in the environment these pollutants can have both direct effects in surrounding ecosystems, i.e. killing local wildlife or contaminating drinking water, and downstream effects such as dead zones caused by agricultural runoff is concentrated in large water bodies.
Agriculture in Namibia contributes around 5% of the national Gross Domestic Product though 25% to 40% of Namibians depend on subsistence agriculture and herding. Primary products included livestock and meat products, crop farming and forestry. Only 2% of Namibia's land receives sufficient rainfall to grow crops. As all inland rivers are ephemeral, irrigation is only possible in the valleys of the border rivers Oranje, Kunene, and Okavango, and also at the Hardap Irrigation Scheme.
Deforestation in the Democratic Republic of the Congo (DRC) is an environmental conflict of international importance. Most of the deforestation takes place in the Congo Basin, which has the second largest rainforest in the world after the Amazon. Roughly half the remaining rainforest in the Congo Basin is in the DRC.
Grassland degradation, also called vegetation or steppe degradation, is a biotic disturbance in which grass struggles to grow or can no longer exist on a piece of land due to causes such as overgrazing, burrowing of small mammals, and climate change. Since the 1970s, it has been noticed to affect plains and plateaus of alpine meadows or grasslands, most notably being in the Philippines and in the Tibetan and Inner Mongolian region of China, where 2,460 km2 (950 sq mi) of grassland is degraded each year. Across the globe it is estimated that 23% of the land is degraded. It takes years and sometimes even decades, depending on what is happening to that piece of land, for a grassland to become degraded. The process is slow and gradual, but so is restoring degraded grassland. Initially, only patches of grass appear to die and appear brown; but the degradation process, if not addressed, can spread to many acres of land. As a result, the frequency of landslides and dust storms may increase. The degraded land's less fertile ground cannot yield crops, or animals graze in these fields. With a dramatic decrease in plant diversity in this ecosystem, more carbon and nitrogen may be released into the atmosphere. These results can have serious effects on humans such as displacing herders from their community; a decrease in vegetables, fruit, and meat that are regularly acquired from these fields; and a catalyzing effect on global warming.
There are many pressing environmental issues in Mongolia that are detrimental to both human and environmental wellness. These problems have arisen in part due to natural factors, but increasingly because of human actions. One of these issues is climate change, which will be responsible for an increase in desertification, natural disasters, and land degradation. Another is deforestation, which is expanding due to human activity, pests, disease, and fires. Mongolian lands are becoming more arid through desertification, a process that is being exacerbated due to irresponsible land use. Additionally, more and more species are disappearing and at risk for extinction. Moreover, especially in population centers, Mongolians deal with air and water pollution caused by industrialization.
Woody plant encroachment is a natural phenomenon characterised by the area expansion and density increase of woody plants, bushes and shrubs, at the expense of the herbaceous layer, grasses and forbs. It refers to the expansion of native plants and not the spread of alien invasive species. Woody encroachment is observed across different ecosystems and with different characteristics and intensities globally. It predominantly occurs in grasslands, savannas and woodlands and can cause regime shifts from open grasslands and savannas to closed woodlands.
Climate change and agriculture are complexly related processes. In the United States, agriculture is the second largest emitter of greenhouse gases (GHG), behind the energy sector. Direct GHG emissions from the agricultural sector account for 8.4% of total U.S. emissions, but the loss of soil organic carbon through soil erosion indirectly contributes to emissions as well. While agriculture plays a role in propelling climate change, it is also affected by the direct and secondary consequences of climate change. USDA research indicates that these climatic changes will lead to a decline in yield and nutrient density in key crops, as well as decreased livestock productivity. Climate change poses unprecedented challenges to U.S. agriculture due to the sensitivity of agricultural productivity and costs to changing climate conditions. Rural communities dependent on agriculture are particularly vulnerable to climate change threats.
The biogeographic regionalization of Earth's terrestrial biodiversity, known as Terrestrial Ecoregions of the World (TEOW), is made up of 867 ecoregions that are divided into 14 biomes. In addition to offering a comprehensive map of terrestrial biodiversity, TEOW also provides a global species database for ecological analyses and priority setting, a logical biogeographic framework for large-scale conservation strategies, a map for enhancing biogeographic literacy, and a foundation for the Global 200.
Fruit production is a major driver of deforestation around the world. In tropical countries, forests are often cleared to plant fruit trees, such as bananas, pineapples, and mangos. This deforestation is having a number of negative environmental impacts, including biodiversity loss, ecosystem disruption, and land degradation.
The severity of desertification in the drylands of the world made the United Nations Organization to adopt a Convention to Combat Desertification (CCD) in 1994. Nigeria approved the National Action Programme (NAP) as a primary tool for the implementation of the Convention in 1997.
