Reading the landscape is at the heart of this blog, not just in the Peak District but everywhere. This book is the book I have been looking for for ages, it brings together all I have learned and more into one volume. As a reminder for myself I made notes as I read it.
The landscape and how to read it
Four landscape forming factors: rocks, soil, climate and living things.
Or two: the natural and the human.
The four factors are constantly interacting. Rocks affect landforms. Landforms affect climate. Rocks and climate affect the soil. Soil and climate affect vegetation. Vegetation affects soil and climate.
Three important themes. Everything changes. Everything’s connected. Everything has multiple causes.
Different timescales: annual, succession, rotational (human controlled).
Rocks: the bones of the landscape
Most fundamental difference is basic v acidic. Basic - alkaline soils rich in plant nutrients, acidic - acid, nutrient poor soils.
Igneous rock: granite, acidic; basalt, basic.
Sedimentary rocks. Sandstone - acidic, nutrient poor soils. Sandy heaths were often common land as they are nutrient poor and often remain as common land now eg Hampstead Heath. Clay - alkaline, nutrient rich soils. Often used as agricultural land. Limestone (including chalk) almost always makes hills as it is so permeable that no erosive surface water remains. Limestone soils are very alkaline but not necessarily rich in other nutrients so not necessarily fertile. Coal measures are the major determinant in urban v rural landscapes.
Upfolds don't always form hills (although they can!). Downfolded rocks are compressed and hardened; upfolds are stretched and weakened. These erode away more quickly than the strengthened rocks of the downfold.
Young rivers form V-shaped valleys which twist and turn. Cultivation is on the hills above the valleys. Glaciers form U-shaped straight valleys where the cultivation is in the valley as the hills above are too exposed for cultivation.
The soil and what plants can tell us about it
Fundamental difference is between the well drained, nutrient poor sandy soils and the alkaline, plastic (and as a consequence not well drained) clay. Clay loams are nutrient rich but plastic (heavy) and was often used for wheat and beans. Easily worked sandy loams were used for vegetables (rabbits and bracken clues to sandy soil).
Soil types. Podsol - acid. Excessive drainage washes nutrients from surface to hard pan below. Often forms on granite and sandstone. Characteristic of heaths and moors. Too acid for worms! Brown earth - not too wet, not too dry. Very good for agriculture. Also found in forests and grasslands. Gley - heavy clay soil with high water table which forms a blue/grey layer. Too wet to cultivate so used for meadow or pasture. Too wet for worms! Peat - extreme waterlogging prevents decomposition leading to peat. Peat can often form when heather forms a hard pan on a podsol leading to poor drainage. Rendzina - thin, alkaline soil on limestone.
Plant indicator species. Strong indicators eg reeds always indicate wet soil v communities. Indicators can tell us about water content, acidity, levels of plant nutrients and light/heaviness. Water content: buttercups - moist not wet; rushes - wet most of year; reeds standing water at least part of year; compacted soil has poor drainage and is often wet - plantain can grow on compacted but not wet soil. Acidity: easy at extremes (heather, acid, old man’s beard, alkaline) but look out for exceptions.
Climate and microclimate
Aspect has an effect but not as much as in other countries or as much as the changes in rock/soil type. Altitude has a much greater effect. It is colder (1C per 100m), windier, wetter and cloudier. Frost pockets form in valleys where the cold air flows down from higher ground. Snow can be used to pick out the wind patterns by studying the drifts. Melting snow picks out the warmer and cooler parts of the landscape. Wind flagged trees show prevailing wind (south west) or effects of local landforms.
Heaths and moors
Heaths are usually sandy lowland areas with poor nutrients. Since the advent of fertilisation many of them were turned into agricultural land and they are now uncommon. Moors form on higher ground, usually acidic in nature. Many are semi natural, formed from woodland by grazing. They often follow the pattern of bracken on the slopes and heather or grass moor on the tops (if the slope is too steep heather will take over as the soil is too thin for bracken). Bracken is a very competitive plant but needs more in the way of bases, drainage and deeper soil than other moorland plants. It hates shallow soil, it hates wet feet: where there is shallow soil heather can grow, where it is wet grass and rushes grow. Alternatively gorse may grow on the slope and bracken a the bottom:
There's gold under bracken,
Silver under gorse,
And famine under heather
Moors are usually managed by burning for either grouse or sheep. Trees are more demanding than most heathland plants and often grow by streams where active erosion releases bases allowing them to grow quicker. Blanket bogs form peat where the rainfall is very high and drainage poor resulting in saturated soil. They are natural as they overwhelm the trees whic can't grow in these wet conditions. In the Pennines they often form on the western side at higher altitude, while heather moors form on the eastern side and lower down.
VEGETATION SUMMARY
The Heather Family
Heather or ling. Poor, acid soil, moist to dry, usually a podsol; tolerates thin soil.
Bell heather. Mixed with heather on drier soils, dominant on very dry ones.
Cross-leaved heath. Mixed with heather on wetter soils, dominant where it's too wet for heather.
Bilberry. Often on drier soil or boulders; shade tolerant and often grows in woods.
Plants of More Fertile Soils
Bracken. Deep, well-drained soil, richer and less acid than typical heather soil, usually a brown earth, usually on a slope; can out-compete other plants on a
favourable soil but is sensitive to trampling; altitude limited by cold.
Sweet grasses (bents and fescues). A mix of fine-leaved grasses, usually grazed down short because the animals like them; they grow on similar soils to bracken.
Gorse, common. Slightly poorer soils than bracken but sometimes more alkaline; not cold-tolerant.
Gorse, dwarf and western. Much smaller plants than common gone with similar soil preferences to heather.
Plants of Wet Soils
Matgrass. Similar soil to heather but often a bit wetter; both it and purple moorgrass may take over where heather is overgrazed.
Purple moorgrass. Similar soil to matgrass but usually a bit wetter still; often grows in big tussocks, especially when in a pure stand - very hard going for
walkers.
Bog myrtle. Wet to very wet soil, often with purple moorgrass; like the alder tree, it's a nitrogen-fixer.
Deergrass. Deep peat and bogs, very wet and acid.
Cottongrass. Bogs, even wetter than deergrass and including open water.
Bog moss. The ultimate peat-forming bog plant, only found in extremely wet conditions.
Water in the landscape
Springs form at the junction of permeable and impermeable rock such as limestone and clay. This is often at the boundary of hill and dale. Villages often built near a spring on this boundary with access to grazing and arable land.
Bogs can also form in valleys.
TYPES OF BOG
Blanket. Forms in regions of extremely high rainfall; covers all flat and gently sloping land in a layer of peat. Always acidic.
Valley. Forms in a low place where drainage is impeded, fed by drainage water. Can be acid (bog or moss) or alkaline (fen).
Raised. Forms on top of a valley bog, fed by rainfall. Always acidic.
The rest of the chapters in the book are less relevant to the Peak District or to my particular interests so I have only outlined them here.
The history of the landscape. Very interesting chapter about the farmed history of the landscape including the enclosures.
The three chapters wild animals and how to recognise their signs, niches or how plants and animals make their livings and succession how landscapes change through time are more about ecology than geology.
Woods play a large role in the landscape and there are three chapters are all about them - trees as individuals, the different kinds of woodland and how woods work. Lowland grassland, hedges & other field boundaries, and roads & paths complete the book contents.
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