Mass extinctions - why they matter even to people who do not care about environment?

Sunnuntai 28.6.2020 klo 20:13 - Mikko Nikinmaa

In a recent issue of Proceedings of the National Academy of Science (USA) Caballos et al. wrote an article “Vertebrates on the brink as indicators of biological annihilation and the sixth mass extinction” (PNAS 117(24): 13596-13602, 2020). It is a clear account about how many terrestrial vertebrates are on the brink of extension. While the message of human role in extinctions is very clear, the present extinction rate being about 1000 times greater than the background rate, it is very difficult to get people who do not care of the environment to realize that it also matters to them. One of the salient points of the article is that the disappearance of one species affects the well-being of other species.

People, who don’t care of the environment, usually care about themselves. Only few people have been against Covid-19 restrictions. What they often do not realize that the Covid-19 pandemic is associated with the extinction wave. One of the biggest reasons for extinctions is the fact that increasing proportion of land goes to human use because of our population growth. As a result, the remaining wild animals come in closer contact to humans and tame animals than earlier. This increases the likelihood of animal micro-organisms reaching humans and consequently zoonosis (i.e. diseases transmitted from animals to humans). It is no wonder that the number of diseases transmitted from animals to man has drastically increased in 2000’s: MERS, SARS, Ebola, Chicken flu, Swine flu and now Covid-19. Even if one does not care about environment, one should care about one’s health.

Also people, who do not care of the environment, must eat, and they IMG_20170807_0146.jpgmay like blueberry pie. About three quarters of all our food plants require insect pollination. Currently pollinating insect populations are decreasing drastically, and the worst scenarios suggest that we cannot eat blueberry pies within 50 years, because of lack of pollination. There are two reasons for the decreasing insect populations. The first is the heavy use of insecticides, and the second the reduced land area for insect refuges (i.e. land areas, which are not in heavy agricultural or other human use). Again, the increasing human populations exert the most important pressures, and to enable sustainable agriculture, one should be able to stop population growth.

While Caballos et al. article did not consider aquatic animals, they are also suffering from extinctions. The worst scenarios suggest that overfishing causes extinction of most important commercial fish species before 2100. In addition to overfishing, aquatic pollution causes the extinctions. Thus, the problem affecting the diets of people not caring of the environment, is caused by mass extinctions.

The mass extinctions themselves are the result of growth ideology. To be able to have reasonably good life for everyone, we should be able to abolish inequality.

Kommentoi kirjoitusta. Avainsanat: land use, insecticide, agriculture, population growth

Reaching another tipping point: insect declines and food production

Lauantai 9.5.2020 klo 18:11 - Mikko Nikinmaa

Three quarters of the plant food we eat requires pollination. Intensive agriculture has been able to increase yields partly with the help of heavy insecticide use.

The two above sentences are in direct contradiction, as pollinators are insects. Harmful insects and beneficial insects are equally killed by insecticides. For a long period of intensive agriculture the negative effects of insecticides on pollinators were not seen, as adequate areas remained outside intensive agriculture to enable effectiveIMG_4119.jpg reproduction. However, it now seems that we have reached a tipping point, where increased intensive agriculture with heavy insecticide use decreases yields. Tipping point means that any further increase in insecticide use results in catastrophic decline of insect populations, whereby pollination  is reduced and consequently agricultural production decreases markedly. This conclusion is based on the observations that insect populations have already decreased in size, and that an increasing proportion of land must be used for agricultural production to feed the ever-increasing human population. Because of this, the insecticide-free refuges for pollinators are disappearing with increasing frequency.

The media discussion at the moment concentrates mainly on neonicotinoids, but actually the type of insecticide does not matter much, because they all have a negative impact on bee and bumblebee populations. In addition to the direct effects of insecticides on bees, it is possible that the recent serious outbreaks of viruses in bee colonies are affected by insecticides reducing the efficiency of insect immune system.

The declines of pollinator populations and consecutive reduction of yields of agricultural products are another symptom of the overuse of the planet, the other notable ones being coronavirus pandemic and climate change. For climate change the reasons are overconsumption in rich countries, inequal distribution of wealth and population growth, for the other two mainly population growth. Because human population has increased beyond sustainability, major efforts should be directed towards population control. It should be done in a way that it is not seen as rich countries again imposing colonial rule. Maybe shifts in wealth distribution could help?

 

Kommentoi kirjoitusta. Avainsanat: insecticide, agricultural production, population growth

What to Wear?

Keskiviikko 26.2.2020 klo 11:48 - Mikko Nikinmaa

Virtually all clothing is today made of cotton, polyester or their mixtures. Presently textile industry is one of the biggest causes of environmental contamination and uses a lot of energy largely produced with fossil fuels. One of the problems with clothing is that the life cycle has decreased a lot with increasing GNP. The time that for example trousers are used has decreased to one third of what it was 50 years ago. Thus, one way of decreasing the environmental footprint of clothing is to use them longer. Another is to recycle them, certainly most of us in Europe and North America have nearly unused clothing in our cupboards, which could be recirculated. If a piece of clothing is not in adequate condition to be sold, it could theoretically be recycled to produce new clothing. However, already this presents difficulties, since most clothes are cotton-polyester mixtures, and remaking usable cloth from the mixtures is nearly impossible with present methodology.

However, even though longer use and recycling of clothing decreases the environmental footprint of textile industry, it does not abolish it. New clothes are needed all the time, and both cotton and polyester have significant environmental impacts. Every time one washes polyester-containing clothing, some microfibres, microplastics, end up in spinnova-sustain-20180123-WEB.jpgwastewater. Although modern wastewater treatment plants remove 99 % of the microplastics, some still end up in our rivers, lakes and seas. With recent discussion about microplastics it is hard to realize that the problem with cotton is much worse than that caused by polyester, but it is! First, cotton uses up very much land in subtropical and tropical areas, where land would be needed for food production. Second, cotton is cultivated in semidry areas, where it uses up virtually all water. The water is thus taken away from food production. The problem would be slightly smaller, if the profits from cotton would come to the local people, but this is not the case. Third, cotton cultivation is the most insecticide-intensive branch of agricultural production. In addition to insects, millions of birds are estimated to die every year because of eating the insects dying as a result of pesticide treatment.

In view of the above, an environmentally thinking person is faced with a dilemma: what to wear, since pretty much everything is environmentally unsustainable. The solution to this dilemma may be soon forthcoming. Start using clothes made of wood fibre. The Finnish company Spinnova has, together with Marimekko made the first experimental batches of clothing using wood fibres produced with their method. In addition to removing all the problems with cotton, the production can be carbon neutral. Further, if trees are planted to some of the arid areas, where cotton is presently cultivated, the area may become more moist (it appears that the presence of trees somehow helps to increase rainfall).

So, after a few years of asking for sustainably produced clothing, we may be able to change our rags to new clothes. One may hope that also dyeing them is done in a more environmentally-friendly fashion than is today done with cotton cloth in major producers like India, Pakistan and Bangla Desh, where cloth dyeing is a major source of aquatic pollution.

Kommentoi kirjoitusta. Avainsanat: climate change, land use, microplastics, insecticide, water shortage

Feeding people - Agricultural practises and land use

Lauantai 19.1.2019 klo 12:20 - Mikko Nikinmaa

Ohdake.jpgOut of the world's area, 71 % is sea and 29 % land (including inland water). Out of this 29 %, about 71 % is habitable. About 50 % of this habitable area is used for agriculture: the area is much larger than that occupied by real forests (36-37 %), scrubland (10 %, much of this is eroded farmland) or urban areas (2 %). Most of the agricultured land is pasture (77 %). Thus, all the crops for human food are cultivated in less than 25 % of the agricultural area.

The absolute amount of land that is used for agriculture is not increasing any more. New land is taken into use more or less in the same area as is lost as cultivated soil becomes infertile. The new cultivated land is mainly obtained through deforestration in the tropics. This means the loss of biodiversity and a decrease of the carbon dioxide sink of the forests. 

Although the human population has increased markedly in the past fifty years, the amount of feed per capita has also increased. This has happened via "green revolution", the increased yields per area partly as a result of the use of artificial fertilizers, irrigation, pesticides and high-yield strains of cultivated plants. There are, however, several downsides of the high-efficiency agriculture. First, it depletes the soils, which can become uncultivable. However, even if the fertility of the soil can be maintained with the use of artificial fertilizers, they leach in the inland waters, which are a limiting commodity anyway, and their eutrophication generates all sorts of problems for aquatic life. Irrigation improves the immediate water availability in cultivation, but it leads to overall decrease in ground- and lake water, as seen in Aral lake, Israel and California. Decreased groundwater levels can be one of the reasons for the Californian wildfires. Artificial fertilizers are, further, mined, and easily reached sites are more or less depleted. The use of pesticides is counterproductive, since non-target species are affected. Because of marked insecticide use it has already been suggested, and the results indicate clear correlation, that the decrease of beneficial pollinator populations is caused by the indiscriminate use of insecticides. The above examples indicate that the yield increases of "green revolution" may be temporary, and carry a heavy cost to the environment.

In view of this, it appears that there are three possibilities to decrease the need for inreased agricultural land use. All of these are also important ways to combat climate change. The first is to limit population growth. To do this, especially women's education should be improved. The second is to decrease the number of farm animals, especially ruminants whereby the proportion of agricultural land as pasture fields can be decreased and crop cultivation increased. This will decrease the amount of methane produced. Third, production ofedible plants close to their sites of consumption, e.g., aquaponics in cities, should be encouraged. This decreases transport distances for agricultural production.

Kommentoi kirjoitusta. Avainsanat: climate change, erosion, insecticides, biodiversity