Environmental Management: Principles and practice

Drylands
Like alpine and high-latitude regions, dryland (i.e. seasonally dry as opposed to arid
environments) vegetation, soils and fauna are under stress, and so are easily damaged,
can be slow to recover and difficult to rehabilitate. Drylands are areas where
agricultural productivity is limited by periodic shortage of moisture and where fire
damage may be common. Roughly 20 per cent of the world’s people live in drylands
and many of these are suffering as a consequence of the breakdown of traditional
livelihood strategies and land degradation. Some drylands have had marked human
and livestock population increases. The reasons for this are diverse, and include:
provision of medical and veterinary services, improved water supplies.
Drylands degradation (‘desertification’) has attracted much attention and has
generated many misinterpretations (Mainguet, 1994; Thomas and Middleton, 1994).
Since the 1960s problems with drought and desertification have prompted interest in
environmental management (Beaumont, 1989; Dixon et al., 1989; Stiles, 1995),
improved rangeland management, savanna management (Mott and Tothill, 1985;
Werner, 1991; Young and Solbrig, 1992), rehabilitation of degraded drylands,
sustainable development of drylands, and coping with fire. There has been limited
success in countering dryland environmental problems. This may partly be because
these areas have experienced considerable unrest and warfare, but also because

---

CHAPTER TEN
198
governments have neglected these areas or intervene in a heavy-handed way with
inappropriate strategies. In drylands care must be taken to be sure of the cause of
problems and of the environmental and socioeconomic parameters.
Areas with sensitive and vulnerable soils
There are areas of sensitive and vulnerable soil in many different environments
(Figure 10.3). Some soils dry out quickly, some lose their organic matter easily
through oxidation if disturbed (a problem in drylands) or drained (a problem with
peatlands). There are soils which shrink, crack, develop crusts or concretionary
layers. Infertile, acid-sulphate soils may develop on drainage, and there are areas
where aluminium and boron deficiency pose an immediate or potential threat
(especially if there is acid deposition). Loess soils and similar fine-grained loams
wash and blow away easily if disturbed and require skilled land husbandry if
production is to be sustained. Soils which are fine-textured allow salt-carrying
groundwater to rise and evaporate leaving a saline crust unless there is enough rain
or irrigation to leach salts away.
The key needs are for environmental managers to understand the soils they
deal with and to promote appropriate soil and water management—put simply,
to ensure good land husbandry (Hudson, 1992). To some extent global warming
and other fashionable development issues have sidelined concern for soil
degradation, which is unwise, for without good soil, food production cannot be
sustained. In a number of countries soil degradation disasters have galvanized
interest, notably in the USA midwest Dust Bowl during the 1930s. Many agencies
warn that soil degradation is bad in developed and developing countries and it
rates as one of the world’s major environmental threats. Nevertheless, soil
conservation and land husbandry are not attracting priority attention and funding.
Many countries are spending too little to counter soil degradation, and some
have even cut back on their efforts. The growth of interest in environmental
management in the UK, Europe and the USA has not been matched by stronger
support for soils research and extension services. Indeed, in the UK quite a number
of geography or earth sciences courses at universities now have little or no
coverage of soils! A historian looking back on the late twentieth century may
well be puzzled by this obvious weakness.