Emissions into waterways caused by forestry are diffuse
Forestry's impact on water is difficult to measure. Forestry has an influence over vast, scattered areas and the characteristics of each area and its distance from waterways significantly affect emissions levels. There are also variations in the quality and extent of measures intended to protect water resources.
Emissions from forestry are categorised as diffuse pollution emissions. All forest areas, regardless of whether they are used for forestry or not, produce nutrient and solid emissions through natural processes. It is difficult to separate the impact of natural leaching from that of forestry, but according to different estimates, the forestry sector in Finland accounts for 3% to 15% of total nutrient emissions into waterways in different areas, in terms of nitrogen and phosphorus.
A wide range of water resource conservation methods
There has been a growing emphasis on water protection in forestry for decades, and this progress is likely continue. Protection of water resources is an integral part of the requirements laid down in forest certification systems. The recommendations for sustainable forestry management and forestry practitioners' own guidelines provide solutions for managing the impact of forestry on waterways.
Available solutions include maintaining buffer zones along waterways during logging and forestry operations, as well as excavation breaks, sludge pits and surface run-off fields. Separate guidelines have been drawn up for groundwater areas, including restrictions for fertilisation and ditching. Generally, all operations must be planned so that the leaching of nutrients and solids can be prevented through careful site planning. Soil preparation on sloping ground is a good example of this. It should be carried out according to the topography, positioning the dig face against the direction of leaching and leaving the areas most likely to erode untouched.
There are various ways to protect water resources. Often, the challenge is not the lack of suitable protection solutions, but the selection of the right solution and the extent of its application, taking into account the characteristics of the work site. The impact of the conditions should also be kept in mind.
The growing importance of planning work
As the climate is constantly changing, future harvesting operations will face even more challenges and the protection of water resources is set to become a key challenge. This is yet another reason why the prevention of climate change is so important.
Careful planning and precision of application are required on a larger scale, in addition to site-specific versions. Topography and changes in elevation divide the land into catchment basins, which are continuous areas from where surface water flows towards the same spot, the so-called 'point of discharge' of the catchment basin. Finland has thousands of smaller catchment basins, but the land can also be divided into catchment basins that are based on larger waterways. The same logic applies to these basins too.
When we analyse catchment basins in forestry, the emphasis is on the smaller-scale basins. At the time of writing, water protection measures are not yet commonly planned on the basis of individual catchment basins, but this is likely to be established as a common practice in the future. The idea is to base water protection measures on the scale of the catchment basin to ensure they are sufficient for managing the emissions from forestry operations throughout the entire catchment basin. Eventually, this means that the planning process takes into account both the extent and characteristics of work sites, securing temporal continuity and at the same time drawing on past experiences and looking towards the future. The forestry plan as a basic tool for forestry provides a very good platform for tackling this challenge.
Legislation and certification leading the practice
Let's look back to the start of this text — the bank of the spring. This is the perfect place to find reasons why the water protection measures described above are so important. According to the Forest Act, springs, streams and brooks, along with their immediate surroundings, are some of the most crucial habitats that must be preserved. This section of the Forest Act aims to preserve the biodiversity of nature.
Springs are also mentioned in another legislative act: the Water Act covers spring basins and the preservation of their natural state. The Water Act lays down more general provisions with respect to preserving the quality of waterways and the authorisation requirements for alterations. These provisions aim to ensure that water conditions remain good, which is vital for nature and a functional society. The Environmental Protection Act includes a general prohibition against pollution, which also applies to waterways.
If we consider the spring in the picture and the forest regeneration in its vicinity in light of the above-mentioned issues, a possible solution emerges. A sufficient, wooded buffer zone is left around the spring when logging. Any direct leaching towards the spring is prevented and the water economy of the spring is not altered when preparing soil. Another thing to bear in mind is that equipment used during regeneration should not be washed in natural waters.
Legislation and forest certification guide the practices by setting boundaries for individual cases. However, they do not comment directly on the importance of clean surface water and groundwater, or on the significance of rich waterway biodiversity to the individual, communities and the entire 'Finland' brand, although these concepts most probably lie behind the regulations. Overall, the condition of our waterways is still very good, and this is an advantage we cannot afford to lose.
Sometimes it feels as though issues surrounding our water resources are taken for granted in Finland, but this is not the case everywhere in the world. I had guests from China last year and their schedule included hiking in the forest, a lakeside sauna and a dinner. My jaw dropped when one of the guests asked if they could really swim in the lake and whether the water was clean enough. This question was asked while we were standing by a quiet, practically untouched lake in the middle of a forest, and it once again opened my eyes to the reality of the situation elsewhere in the world.
