Executive Summary

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1.0 Study Objective

The Wairoa District has become an increasingly attractive area for investment forestry. By early 1994, sections of the community were expressing strong concern that this would have a detrimental effect on the people of the District. Forestry appeared to be displacing traditional pastoral farming, which provided both the social infrastructure in rural areas and employment in processing and support services in the urban areas.

This study focuses on two key impacts of land-use change from hill-country pastoral farming to plantation forestry in the Wairoa District Council (WDC) area - employment and household income. It also addresses demographic, infrastructural, and environmental impacts at a generic level and identifies key social issues that require further consideration. This summary and the full report are resource documents that provide background data and analysis of change for the future use of the Council and community groups.

This executive summary follows the same order of chapter headings as the main report.

2.0 Wairoa District - Population and Employment

  1. Total population in 1991 numbered 10 266, a decline of 8.3% from 1981.
  2. A total of 3326 people (32.4%) were in paid work (self-employed and wage or salary earners) in 1991. This was a decrease of 13.5% from 1981.
  3. From 1986, unemployment rose consistently to a high of 1350 in December 1992. This was followed by a steady decline to 830 currently (NZ Employment Service, April 1995).
  4. Industries are ranked in order of importance according to the size of their workforce:
Industry groupings 1991 workforce
Agriculture, forestry, and fishing

Community, social, and personal services

Manufacturing

Wholesale, retail, restaurants, and hotels

Building and construction

921

867

627

492

192

Total

3099

These industries employed 89% of the paid workforce as at 1991. These employees were engaged in the following businesses.

Business sector NZSIC Codes Statistics New Zealand (1992)
Number %
Primary sector (excl. farms) 1 (excl 111), 2 36 9
Manufacturing

3 (excl. AFFCO)

16 4
Commercial services
Trades 5, 95 57 14
Retail 62 72 18
Hospitality 63,94 34 9
Business 8 27 7
Other 4, 61, 7 63 16
Social / community services 93 63 16
Public administration

91

31 8
TOTAL 399 100
  1. In 1991, only 36 workers are recorded as being involved with the Forestry and Logging industry (a component of the grouped industry of Agriculture, Forestry and Fishing above).

3.0 Land Use and Physiography

The Wairoa District Council area is predominantly steep to very steep hill country, much of which is susceptible to erosion damage. Approximately 60% of the total land area is in use, and 47% is in grass.

Summary land-in-use statistics (Statistics New Zealand, for the year ended 1993)

Total land area (ha) 412 750 100%
Conservation estate (ha) 152 212 37%
Number of holdings 443
Total area (land holdings) (ha) 260 536 63%
Grassed area (ha) 194 149 47%
Plantations (ha) 33 419 8%
Other land (ha) 32 968 8%

The generally steep river valley systems that have developed in the District on relatively recent sedimentary rocks indicate that erosion is a naturally occurring process and has been significantly active over recent geological time. The removal of the original forest cover and replacement by short grasses and grazing animals has accelerated that rate of erosion. This has been recorded by farmers and scientists alike since the late nineteenth century.

4.0 Pastoral Farming

Provisional 1993 data from Statistics New Zealand indicate that the average holding size was 588 ha and the average grassed area per holding was 438 ha. For the estimated 300 pastoral farms in 1993, the average grassed area per farm is calculated as 647 hectares.

The total livestock units (LSUs) changed over the period 1981-93 as follows:

Year

Total LSUs LSUs per ha in grass

1981

1986

1991

1992

1993

1 799 994

1 816 449

1 552 375

1 505 741

1 502 701

9.12

9.36

7.81

7.86

7.74

Livestock numbers increased until the mid 1980s encouraged by Government-funded land development schemes, livestock product pricing policies (SMPs) and other subsidised assistance provided to the agricultural sector.

The main reasons for the decline in stock number after 1986 included falling fertility due to severe cutbacks of fertiliser on marginal land, low product prices, high interest rates, changes to livestock taxation, Cyclone Bola damage, the 1989 drought, and, more recently, changes in land use from pastoral to forestry enterprises. The decrease in livestock numbers between 1986 and 1993 amounted to 17.3% in total.

Sheep and beef cattle comprised 96.6% of total livestock units at 30 June 1993. In total, sheep LSUs have decreased by 27.2% and cattle LSUs by only 3.0% in the period 1986 to 1993.

Information obtained from a 1994 survey of Wairoa pastoral farmers:

  1. Farms under 800 ha are substantially owner-operated, with contract assistance for intensive tasks requiring more than one labour unit, e.g., shearing.
  2. Farmers indicated strong support for locally based workers, although a number of the larger properties use shearing crews from outside the District.
  3. Eighty-two percent of surveyed farms are family-owned and operated. A further 11% are privately owned and employ a manager. The latter tend to be the larger farms managed on behalf of absentee owners and, when added to the Trust or Incorporation-owned properties, these make up by area and stock numbers a substantial proportion of the District.
  4. An analysis of farm manager age identifies a considerable proportion of managers in the over 50 years categories, particularly in the smaller farm classes. This suggests that there will continue to be a steady number of properties coming to market as owner operators retire.
  5. On average, 82% of the land classed as grassed area in the Agriculture Statistics is in managed pasture, with an additional 5% in grazed scrub. The remaining area is in other uses. Woodlots make up a very small proportion of land area at 2% or less across all farm classes.
  6. Sixty-five percent of farms in the survey received off-farm income in the 1993/94 year. At current gross margin levels a farm of 4000 stock units (400 ha to 500 ha) is considered to be a viable one-family unit in the Wairoa District (H. Collier, pers. comm.).
  7. In expenditure terms, survey results confirm that the farming sector strongly supports local businesses even though some major inputs - e.g., fertiliser, fuel, and vehicles - are effectively purchased externally, the local suppliers being agents of importers or manufacturers.

5.0 Forestry

This study estimates the Wairoa District plantation forest resource at approximately 35 000 ha at 30 June 1994 with 57% less than 16 years old. This estimate was based on the 1993 Agriculture Statistics and a survey of large forest growers. Production forestry is dominated by the corporate growers, investment partnerships, and companies, and by a small number of large private growers.

Wairoa Plantation Resource Identified by Survey
Forest growers Estimated plantation area at 31 March 1994 (ha)
Corporate forest growers

Investor partnerships and companies

Other growers

23 400

4 500

1 700


Total

29 600

Production forests currently contribute at least 120 full-time equivalents of employment, but only 25% to 30% of these are captured within the District, according to a survey of major forest growers.

Direct expenditure on the major forests in the Wairoa District exceeded $6.3 million in the 1993/94 financial year. Just over 25% of this was spent in the District. While there are some costs which will always occur outside the District, approximately $1.2 million of expenditure ($0.86 million in establishment, $0.32 in tending) spent externally could have gone to Wairoa-based contractors. An additional $2.3 million is spent outside the District on logging and loading.

The following publicly available information has allowed us to make some tentative forecasts:

  1. Juken Nissho Ltd have stated an intention to expand their East Coast resource by 30 000 ha over the next 30 years. A substantial proportion of the Company's new planting could reasonably be in the Wairoa District.
  2. Private investment partnerships and companies have been planting 2000 to 3500 ha per annum over the past two years, and have some area already available for planting in 1995. Steady demand is forecast, although at a lower level from present.
  3. CHH Forests have recently purchased additional land for new establishment.

As a result of these factors we have used the following schedule of new planting in this analysis.

Year Likely (ha) Upper estimate (Ha)
1994 (estimated actual) 5200 5200
1995 (forecast) 3500 4500
1996 2000 3000
1997-1999 2000 2000
2000-2024 1600 2000

6.0 Recent Land Use Changes in the Wairoa District

6.1 Farm sales - 1989 to 1994 (Valuation NZ data)

Sixty-eight properties have been sold during the period 1989 to 1994, with a high of 16 in 1990. On average 8650 ha/annum of farm land has changed hands. The most marked change has been in the purchasers of farm properties, as summarised in the following table.

Year Number of properties purchased, and use for which they were destined
Nationally Wairoa Farming Forestry
1989

1990

1991

1992

1993

1994

121

153

98

135

137

97

13

16

6

10

12

11

13

16

6

8

6

3

0

0

0

2

6

8

Total 741 68 52 16

The total area of land sold to forestry since 1992 is 12 130 ha. Of this, 242 ha have been subdivided and resold as lifestyle holdings or intensive farm units with farm buildings.From these estimates, a total of 86 150 stock units has been displaced to date from the 12 130 ha purchased by forestry interests.

Analysis of sales over the past five years suggests that purchases by forestry interests have generally been of more intensively managed properties than farmer purchases. Properties that have been sold, however, have tended to be less intensively managed than the District average.

6.2 Pastoral property price trends - 1989 to 1994

Prices paid for pastoral farms in the Wairoa District have been driven up significantly by forestry buyers in the period 1992 to 1994. Data from 1989 to 1992 suggest that sale prices were relatively constant at 70-75% of the national average for hill-country pastoral farms. In 1992, however, forestry buyers entered the District, paying prices consistent with the national average. Since then prices have increased dramatically, and currently are approximately 119% of national average.

Pastoral farm sale prices ($/LSU) - 1989 to 1994
Year Sale price ($/LSU)
  Nationally Wairoa Farming Forestry
1989

1990

1991

1992

1993

1994

98

103

98

122

146

164

71

76

72

101

130

195

71

76

72

83

114

164

0

0

0

121

145

206

7.0 Trends in Farming and Business in Wairoa

Statistical data describing the structure, constraints, intentions, and opinions of the Wairoa business and farming sectors are derived from mail surveys conducted by the authors in September 1994. Response rates were 36.5% for the business surveys (97 of 265) and 33.2% for the farmer surveys (95 of 286).

7.11 Employment and output expectations of survey respondents

Analysis of business survey respondents recorded no significant change in total employment or the volume of business across most industries over the past five years, although levels have fluctuated. The last 18 months has seen an upward trend in demand for products and services.

Businesses forecast continuing improvement in the volume of demand, particularly in the primary, manufacturing, construction, hospitality, and business service classes, but do not expect any major movements in employment in the coming five years. However, the retail trade remains cautious, with a number of businesses indicating that closure was possible, and only a small number forecasting increased trade.

The farming sector has seen an improvement in employment over the past five years. This is reflected most strongly on the 400 ha to 1500 ha properties as both full-time and casual employment. Increases have averaged 0.2 to 0.4 full time equivalents (FTEs) per property.

Forestry-related employment has increased rapidly since 1993 and, on the basis of trees already in the ground, offers substantial new opportunities in the next 15 years. The following estimates of direct employment were derived by modelling the existing forest resource and its labour demands to the end of the current rotation, and assuming no new planting.

Forecast contract employment in Wairoa District (1995-2024)
Work type Work available (FTEs)
1994 1995/99 2000/04 2009/10 2010/14 2015/19 2020/24
TENDING 30 47 45 24 39 50 45
Logging/loading

Transport

Roading

HARVESTING

28

12

4

44

33

12

4

49

71

16

3

90

130

35

6

171

169

63

10

242

161

83

12

256

131

77

10

218

Other 2 2 2 2 2 2 2
TOTAL 76 98 137 197 283 308 265
7.2 Changes in business and farming strategies

Almost 60% of businesses responded that they had altered their business strategy in the past five years. The three most common strategies were to alter product or service range, to change operating hours, and/or to restructure debt. This adjustment is forecast to continue into the next five years, with 11% of businesses considering capital investment in building, and 32% indicating that further investment in equipment was likely.

Investment in farming is also increasing. In the past five years substantial additional investment has been made across all farm classes in increasing fertiliser applications, increasing repair and maintenance expenditure, and replacing equipment, e.g., farm bikes. Fifty percent of farmers have increased fertiliser applications, 40% have increased maintenance expenditure, and 65% have increased expenditure on equipment. Less than 11% have reduced these expenses.

7.3 Critical factors impacting on Wairoa businesses

Respondents to the business and farming surveys ranked critical factors impacting on their commercial activities as follows.

Businesses Farmers
Unemployment Product prices
Farm incomes Droughts
Government policy Input and interest costs
Climatic events Government policy
AFFCO employment Storm events
Forestry development Forestry development

Farmers were asked about changes in community structure over the past five years, and their significance. A high proportion (over 85%) indicated that no changes had significantly affected them. Where impacts were reported these included declining rural school rolls (12%), diminishing rural school bus services (10%), reduction in rural retail outlets (stores, hotels, post offices), changes in the frequency and quality of freight services, and a decline in agricultural services.

7.4 Business confidence

In general terms, across both the farming and business sectors, business health is judged to be mediocre to good and there is a trend towards gradual improvement. Farmers are consistently more positive than business people, both in their assessment of business health overall and in their confidence in the future prosperity of their businesses.

Manufacturing, construction, and hospitality/tourism are the most positive of the industry classes.

7.5 Impacts of afforestation on local businesses

Recent afforestation of 12 130 ha is only approximately 6% of the area in pastoral use in the District. However, 30% of businesses perceived an impact from the forestry expansion on their business over the past five years. Industries indicating the strongest responses were the primary sector, wholesale trade (e.g., stock and station agents), utility suppliers, and retailers.

Most, but not all, impacts reported were negative. In the service classes they related to decline in farm spending, rural population, and the number of farm clients; and in manufacturing, to the decline in livestock numbers. Five percent of respondents recognised an increase in business from forestry-based expenditure.

An increased proportion of businesses expected some impact in the future, with the major concerns again reduction in farm spending, the potential threat to AFFCO, and the export of profit and capital expenditure.

7.6 Impacts of forest development on the farming community

To date, 40% of farmers identified an impact. Almost half of these referred to the increase in land values. Some identified this as positive in terms of improved equity and the opportunity to sell some land and reduce debt. Others described the resulting increase in rates as a negative, or forecast a long-term decline in value as forestry became a dominant land use. The other area of impact which received a reasonable amount of support was the restriction on certain activities, e.g., fire and the liability risk that forestry as a neighbour generates.

Seventy-three percent of farmers expected to be affected by forest development in the future. Three concerns received consistent support across all farm classes: (a) a potential decline in rural services, (b) an increase in road damage and maintenance costs, and (c) a breaking down of the rural community structure and increasing isolation.

7.7 Community and environmental issues

In order to put into context the concern over changes in land use, survey respondents were asked to list the three most important community and environmental issues from their perspective. There was strong agreement across both sectors that the key community issues were (a) unemployment, (b) crime, (c) the future of health services, (d) a lack of motivation/confidence, and (e) the need for well targeted, effective training and education opportunities. These five issues received greater than 10% support from both sectors, with unemployment receiving over 50% support from both sectors.

People's perceptions and concerns on environmental issues were more varied. Erosion and forestry development both received strong support from both sectors. Effluent disposal, drainage, and water quality also received more general support.

8.0 Impacts of Land Use Change on Farming and Meat Processing

To analyse the regional effects of afforestation on pastoral land, a base scenario of land-use change over 30 years has been developed.

Planting year Hectares
1995 3500
1996 2500
1997-99 2000 p.a.
2000-2024 1600 p.a.
Total planted area 52 000 ha (over 30 years)
Total reduction in LSUs 400 400 LSUs (over 30 years)
Total salvage value of livestock $24.5 million
  1. The agriculture-related employment loss increases in total from 9 FTEs in 1995 to 237 FTEs at the end of the 30-year period of land-use change. Approximately 57% of the employment loss is associated with on-farm labour (including owners).
  2. The loss in gross household income related to the agricultural sector increases from $0.66 million in 1995 to $9.79 million p.a. after 30 years of land-use change. These agriculture-related losses increase from 0.9% to 13.6% of the current district total over the 30-year period.

The contribution to the loss of gross household income from the agricultural sector is summarised as:

On farm 68.7%
Farming indirect 22.9%
Meat processing direct and indirect 8.4%

The reduction in agriculture-related employment and income in the servicing sector has been included as the indirect components of the analysis. The reduction in demand is estimated as follows.

% Reduction of inputs and services
Year (farm-related)
2004 (after 10 years) - 9.0
2014 (after 20 years) -16.2
2024 (after 30 years) -23.4

Businesses likely to be most affected by the land-use change are:

  • Veterinary practices and farm consultants
  • Fertiliser companies
  • Agricultural contractors
  • Stock and station agencies
  • Transport operators

The impact on the meat processing industry is small under the assumptions made and the current rate of annual kill. The analysis calculates a loss of only 29 FTEs after the 30-year land-use change period, and is less than 8% of the current work-force (estimated at about 400 FTEs).

9.0 Impacts of Land Use Change on Forestry and Wood Processing

The significant factors areas follows.

  1. The silvicultural labour requirements build up to a peak in year 2002 and then fall away to a constant requirement of 79 FTEs by year 2009.
  2. From the commencement of harvest, employment requirements increase dramatically, with or without wood processing. After the early higher rate of planting is harvested, employment requirements for the base scenario level out at approximately 1160 FTEs inclusive of all direct and indirect employment and replanting of harvested areas. This requirement is marginally greater than 30% of the total current workforce in the District.
  3. Gross household income from forestry and wood processing increases from about $2.5 million per annum during the first 28 years, to in excess of $40 million per annum after harvest commences. This is equivalent to an increase of more than 55% on the current level of district household income. This is exclusive of the actual value of the wood itself .
  4. Without wood processing located in the WDC area labour requirements and gross household income related to forestry would be reduced by approximately 50%.

The net impacts on employment and gross household income for the land-use change under base scenario assumptions are presented in Table 3. The net change with local wood processing facilities is summarised as follows.

  1. The gross household income stays relatively static over the first 10 years, and thereafter decreases evenly to a maximum of -$6.75 million p.a. (-9.4% of the current district income) in the year 2022.
  2. Once harvesting at a static rate of 1600 hectares p.a. is reached in the year 2028, the net increase in district gross household income would be approximately $32 million per annum (+44% of current district income). (This assumes local processing facilities.) This scenario would generate over 900 additional FTEs of employment.
  3. Without wood processing facilities, the net change to district gross household income at year 2028 is approximately $13 million per annum (+18%). The increase in employment would be limited to about 350 additional FTEs harvesting, log transport and replanting.

Development of wood processing facilities may occur before the year 2023, on the basis of available wood volumes from existing forests (at 1995) and in the expectation of additional volumes from the year 2023 onwards. This would offset farm employment and income losses at an earlier time.

10.0 Selected Social Issues and Rural Impacts

10.1 Rural depopulation

On-farm employment losses will have the greatest impact on rural districts and communities. Where land-use change is concentrated on particular districts, rural schools may no longer be viable through falling rolls, and other district services such as school buses, rural mail deliveries, and commercial transport may also become non-viable.

Offsetting this effect will be the trend for some of the farm workers displaced by land-use change to move into forestry employment and to continue to reside in the locality. At the same time, lifestyle farmers and/or forest workers may move into the locality of the new forest development.

Some net rural depopulation is likely in areas undergoing land-use change to forestry. The estimates of likely rural depopulation numbers are made at several levels of net outward migration.

Degree of net migration out (%)

Total persons lost at year 2024

No. of persons lost per 1000 hectares

     

25

116

2.22

50

230

4.44

75

346

6.66

100

462

8.88

The age structure of the District's population is assumed constant in these calculations. In reality there may be significant changes in structure because new residents, who use land differently from those who leave, may well be in different age classes.

10.2 School rolls

The impact on rural primary school rolls is broadly estimated using the 1991 census data. This estimate assumes rural depopulation based on the 50% outward migration level, and is summarised below.

Child age across the District at 2024 Total decline in school rolls
5 to 11 years 36
12 and 13 years 10
14 years 5
Total 51

The effect on rural school rolls under this assumption will not be great if the land-use change is spread evenly over the area. However, this is unlikely, and some schools may close.

11.0 Impact of Land Use Change on District Roads

The District roading infrastructure, excluding State Highways, is approximately 820 km, of which 82% is unsealed. Current expenditure is budgeted at $4.5 million per annum offset by a 60% Transit New Zealand subsidy.

Most of the non-arterial rural roads have a carriageway of five metres or less which is generally too narrow for regular use by heavy commercial vehicles such as logging trucks.

The increased use of a particular road by heavy commercial vehicles, particularly at high intensities as with logging trucks, substantially increases wear (Clough & Meister 1987). This may result in road failure where roads are not adequately constructed for heavy traffic or have exceeded their design life.

In addition to potential road deterioration, there are important social issues. These include the rapid increase in the volume of heavy traffic on rural feeder roads used predominantly by farm families, increases in noise and dust levels, and the perception of reduced road safety as a result of increased heavy traffic use.

In the past, forest companies have expressed concern at attempts by local authorities to impose additional revenue collection measures such as differential rating or special grants, rates or bonds on forest owners. Current ratepayers are also concerned at the additional costs of road maintenance and improvement and the subsequent increase in rates that log transport is likely to impose. Local Bodies are also concerned at the difficulty under existing funding mechanisms in spreading road improvements over a number of years before harvesting commences.

It is expected that a number of rural feeder roads will require significant upgrading for harvest use over the next 10 years. These can be planned for with adequate consultation between the WDC and forest companies.

The use of rail as an alternative log cartage system is only likely to be viable once large harvest volumes travelling a considerable distance are available.

12.0 Environmental Impact of Land Use

12.1 Soil loss

The mass movement processes that are most common in the Wairoa District are shallow slip and earthflow erosion (Page 1988). There is considerable evidence for frequent shallow slips under natural conditions (Clough & Hicks 1992). Slipping is induced by short intense rainstorms or prolonged wet weather. The magnitude of slipping in any event is complex. Slipping under pasture occurs more intensely than under forest for storm events of the same magnitude. As a result, average levels of slipping under pasture are between two and ten times greater than under indigenous forest or scrub (Clough & Hicks 1992).

Afforestation reduces the magnitude of mass movement significantly, forests over eight years of age providing results very similar to indigenous forest. There are, however, periods of susceptibility to erosion in a plantation rotation. These occur between planting and canopy closure at six to eight years (Phillips et al. 1990). In subsequent rotations this period of risk is reduced over the first two to three years as the roots of harvested trees provide residual, but declining, cohesiveness (Watson 1990).

Slipping also has a significant impact on pasture productivity in the short term, and on potential productivity in the long term. The study by Douglas et al. (1986) of pasture production in the Wairoa District indicates that on siltstone hill country, maximum recovered productivity under normal management takes at least 15 years and that this is likely to be at least 20% below original levels. This is largely a potential loss, and can be masked by additional management inputs, e.g., fertiliser, improved grasses, subdivision. Land slipping in the District can also have a large immediate financial impact in terms of replacing fences, reinstating tracks and oversowing damaged hillsides.

Disaster recovery grants on the East Coast after Cyclone Bola averaged $83,000 for large farms (>800 ha) and $30,000 for small farms (150 ha to 800 ha). Channelised mass movement (debris avalanches and flows) occur in the very steep mountainous areas under intense rainfall and contribute significantly to river sedimentation (O'Loughlin & Pearce 1982, Grant 1982).

12.2 Soil Degradation

Rates of nutrient loss are primarily determined by (a) rate of soil loss by erosion, (b) loss through product removal (animals, logs) and (c) leaching and volatilisation (especially nitrates). Relative loss rate data are sparse and rarely comparative. The impact of trees on nutrient availability varies and is complex. Studies suggest that trees in low-nutrient soils reduce nutrient availability and those in high-nutrient soils increase it (Smith 1994). The outcome for any site appears to depend on the plantation's effect on the equilibrium between inputs and outputs of organic matter. Fast growth rates and removal of biomass at harvesting can be expected to generate deficiencies in nutrients in marginal supply or alter nutrient balances, which in turn affect tree nutrition.

Nutrient depletion in agricultural systems is primarily caused by leaching, animal transfer and soil loss due to erosion (Hedley et al. 1990). Maintenance applications of key elements are essential components for clover-based pasture systems, to maintain clover nitrogen fixation rates and growth of productive pasture species.

Compaction is likely to be a greater problem in plantation forestry, with the use of heavy machinery in harvesting and roading, than in agriculture, although compaction damage by cattle pugging in wet conditions is quite common. Tree growth is adversely affected on skidder-logged sites and on skid sites where logs are aggregated (Dyck & Cole 1990). Natural alleviation of compaction is slow (Gameda et al. 1994) and compacted soils can reduce soil biological activity, restrict plant root extension, reduce water infiltration and increase surface runoff.

There is evidence of acidification in both pasture and plantation forestry systems. Levels of acidification under pine plantations are less clear, although some data indicates reduced pH levels under plantations when compared with neighbouring pasture sites (Hawke & O'Connor 1992). The long-term impact is yet to be assessed. There is a common concern among pastoral farmers that land managed for production forestry will not easily be able to be returned to pasture production because of acidification. Forest companies' experience with oversowing after harvesting (as a weed control measure) would suggest that this fear is not well founded.

There is little comparative data concerning the relative biological activity in pastoral and forestry soils. Vegetative diversity encourages soil biotic diversity. Fertiliser applications, acidification and/or high-density monocultural plantations may reduce diversity and activity. Mycorrhizal associations in plantation forests benefit soil health, particularly on poorer soils (Dyck et al. 1985).

12.3 Water quality

Water quality in Wairoa rivers is closely related to soil movement (erosion, earthworks) and nutrient movement. All rivers show limitations due to turbidity (sedimentation) (Hooper 1994). In the Waiau river system this is significantly contributed to by natural erosion in the Urewera National Park. The Wairoa and the lowland rivers (Nuhaka, Waihua and Waikare) are further limited by conductivity, ionic concentration and hardness, which at least partially are attributed to existing land use. There is particular concern over the impacts of wastewater discharge from effluent and sewerage treatment systems in the lower Wairoa. A decrease in oxygen concentrations and an increase in suspended solids, bacterial concentrations, ammonia nitrogen and biochemical oxygen demand have resulted in a conclusion by the Hawke's Bay Regional Council that there are potential health risks in participating in contact water sports in the lower Wairoa River and estuary (Sander 1994).

At a national level Regional Council officials rank agriculture as the biggest source of adverse effects on water quality, followed by human sewage disposal (MAF 1992). Forestry was cited as significant but less serious than other sources of water quality problems.

Production forestry involves a number of activities - earthworks, site preparation, establishment, tending, fertiliser use and harvesting - which may influence water quality. Of these activities, roading, site establishment, fertiliser application and skid sites and tracks at harvesting affect water quality most (Priest & Rennes 1979).

Plantation forestry can be expected to improve the chemical quality of water relative to pastoral land. However, burning of harvested sites for land preparation and direct application of fertiliser to watercourses can increase conductivity, total nitrogen and total phosphate levels (Dyck et al. 1981).

Of major agricultural impacts on water quality, sedimentation and nutrient loading of surface water bodies are rated the most serious, with changes to physical characteristics and faecal contamination of surface waters ranked as slightly less serious impacts, followed closely by nitrate contamination of groundwater (MAF 1992). Lakes in predominantly pasture-dominated catchments are often nutrient-enriched, many showing adverse signs of eutrophication (depleted oxygen levels, poor water clarity, scums, blooms of phytoplankton). Work by Howard-Williams et al. (1983) on the Tiniroto and Putere lakes confirm high nitrate and phosphate levels and frequent incidence of algal blooms associated with nutrient enrichment.

12.4 Water yield

The volume of stream flow directly affects both water quality and the availability of water for use. A given amount of contamination, whether it be nutrients, pesticides, sediment or faecal coliforms, will have a greater impact on water quality when there is reduced flow.

Conversion of whole catchments of pastureland to plantation forestry can reduce total annual water yields by up to 50% once the canopy closes (Fahey & Rowe 1992). The impact on low flows is unclear, but peak discharges from small storms may be reduced by up to 80%. The impact on peak flows from large storm events is much lower. These effects may be beneficial as a means of flood protection but may also have serious consequences where downstream users are dependent on sustained flows for irrigation, hydro-electric power, municipal supplies, etc.

Fahey & Rowe (1992) report declines of up to 50% in low flow levels from small catchment studies in the South Island. In contrast, Black (1993) analysed low flow data, comparing exotic forested catchments with a pastoral catchment near Patunamu Forest, and showed that afforestation improves infiltration, storage and average low flow levels if the rainfall is greater than the transpiration requirements. Black concluded that general low water yield in the District occurs regardless of vegetation cover, with a tendency for slightly higher flows in forested areas, and that a change from pastoral to forestry land use would not cause a reduction of minimum flow. He acknowledged, however, that the effects on flow distribution and duration of low flow had not been addressed and required further study. These different interpretations of data have yet to be resolved.

12.5 Biodiversity - vegetation and habitat degradation

Modifications in indigenous vegetation to support productive use have important environmental impacts on (a) water yield and quality, and therefore on aquatic flora and fauna, (b) diversity of plant species, reducing ecological resilience and habitat for animals, and (c) weed introduction and spread. Removal of riparian vegetation, particularly in pastoral systems but also in plantation forestry, results in significant impacts. Riparian zones have a number of functions, but generally they act as filters for sediment- and nutrient-laden water, and provide shade and food for the aquatic communities living in the streams. Riparian zones can also act as corridors for wildlife, providing access to water and routes for migration.

Clearance of native vegetation for planting exotic species can lead to a loss of biodiversity and of habitats for indigenous flora and fauna. The New Zealand Forest Accord, signed in 1991 between conservation interests and major forest companies, made a commitment that native forest, including areas of regeneration, would not be cleared for plantation planting. The Forests Act 1993 limits private owners= ability to clear native forest, but scrub clearance continues in both farm and forest development.

Plantation forestry can harbour exotic invasive weeds which may constitute threats to neighbouring landowners. Weed infestation in plantations has led to intensive vegetation management practices, with heavy emphasis on herbicide use, particularly in the establishment phase. With the cost of weed control increasing and growing pressure against herbicide use, alternative techniques such as oversowing are now being introduced, with economic and environmental benefits.

12.6 Animal pests

Plantation forestry and extensively managed pasture and scrub can all harbour animal pests such as goats and possums. The crucial issue appears to be investment in pest control by land managers. Both sectors and regional authorities invest significant amounts in pest control. Coordination by the Regional Councils provides an opportunity for a fair and equitable pest control programme to be established that benefits all landowners.

Pest control methods continue to be an area of considerable debate, and the use of sodiummonofluoroacetate (1080) is of particular concern. Drench resistance is also an issue, particularly where uncontrolled goats can act as vectors for parasites, as is the risk of cross infection of tuberculosis from possums to cattle.

12.7 Climate change

Trees and tree crops are vulnerable to climate change, since the time scale for the projected increase in temperature is short in relation to their lifespan (Whitehead et al. 1993). Plantation forests are being promoted as an effective means of reducing net greenhouse gas emissions. Scientists studying the Greenhouse Effect believe that every hectare of pasture converted to a typical stand of trees, under a sustainable regime, will store at least 100 tonnes of carbon (Maclaren et al. 1993). The benefits of plantation forestry are largely derived by establishing forests on land currently not in forest cover, and are only long term if the net wood products pool is increasing (Maclaren & Wakelin 1991).

One of the concerns raised by farmers is the potential for local changes in climate as a result of tree planting. While there is evidence to support the impact of extremely large contiguous areas of forest on climate patterns (e.g., the Amazon basin) there is no firm evidence to support changes in local weather patterns through regional afforestation or forest removal.

12.8 Widespread loss as a result of introduced pests

There is widespread concern that monocultural forest plantations are more vulnerable to pest and disease attack than more diverse ecosystems, especially when they are under nutrient stress or derived from limited genetic material (Rosoman 1994).

There is also debate as to whether the long-term health of the radiata pine resource in New Zealand has declined. Opposing arguments state that the genetic base within the species has been intentionally maintained at a broad level and that this confers diversity and resilience. Threats from new pests and diseases are real, and are the focus of an expanding health surveillance programme of forests and at ports of entry (Handiside 1994).

12.9 Aesthetics and landscape considerations

Aesthetics is a difficult subject to address quantitatively. Large areas of even-age plantations of single species provide a homogeneous landscape substantially different from that of pastoral farming. This is often criticised as being monotonous and visually unappealing. Pastoral farming is an extremely familiar landscape to most New Zealanders, and is promoted as typical in much of our international publicity. Landscape architects argue that the challenge in any land use is to establish patterns that are appropriate in form and scale to the character of both the underlying landform and the surrounding landscape.

12.10 Health

Health issues in agriculture suggest that the impact on public health of product quality is of greater importance than plant production (Clough & Hicks 1992). There is potential, however, for faecal contamination to enter waterways or aquifers from a variety of agricultural sources. This can be a vector for disease, potentially causing illness if the water is used for contact recreation, for drinking by humans or livestock, or for food processing. Water treatment costs may be increased and coastal waters contaminated, rendering shellfish unfit to eat.

The most serious health issues in forestry, however, relate to worker safety and the processing of wood products. Worker safety is also an issue in agriculture. The use of toxic chemicals (herbicides, pesticides) and dangerous or heavy equipment (chainsaws, logging machinery, tractors) puts workers at risk.

Some contributors to this report have suggested pollen as a potential respiratory health issue. No data on pollen from plantation softwoods as a potential health risk have been found.

12.11 Fire

After harvesting forests, large-scale burning used to be carried out routinely to reduce the amount of slash and facilitate planting. It is now less widely used because research has indicated that the long-term productivity and sustainability of forests is aided by retaining slash for nutrient recycling. Burning has negative impacts on water quality, nutrient loss and sediment yields because it promotes surface runoff (Dyck et al. 1981).

Plantation forestry is at greater risk of commercial loss from fire than is pastoral land. As a result, regulatory control of some activities on land adjoining forests is common. The commercial risk is imposed as a liability on neighbouring land users, and is of widespread concern to farmers. Recreational use of forests is a potential benefit to the District but can create a major fire hazard, especially where trees are close to residential developments.

13.0 Discussion

13.1 Opportunities

The net benefits to Wairoa District of the employment and income predictions made in this study are fundamentally dependent on the ability of people living in the WDC area to capture them. Currently, much of the forestry-related employment (up to 75%) is being carried out by contracted workers from outside the District. Effective training programmes for both prospective workers and contractors may be necessary for some of these jobs to be captured by local residents. These programmes could focus initially on silviculture, which provides a relatively simple entry into the business of contracting and general forestry skills. Marae or community-based training initiatives may be appropriate.

A WDC policy statement on forestry development might also be appropriate to indicate the Council's attitude toward Wairoa becoming a significant forestry service centre. Such a strategy could address the issues of roading as well as industrial development opportunities. A consistent and clear approach would provide certainty for landowners.

13.2 Social costs and community response

A simple assessment of the potential net employment benefits of forestry development disguises the very real costs that are also incurred. In the case of land-use change these are predominantly carried by the present farming community. There are economic costs of rates increases, the restriction of farm activities and increased liability risk. There are also substantial social costs in changes to existing community structures, perceived isolation, threats to schools and school bus routes, and other services such as commercial transport and rural mail.

Council-supported community debate around the issues raised in this report would be valuable. The development of community initiatives to address changes in particular localities could also be supported. Issues addressed could include school bus services, sponsorship of local community activities and rationalisation of farm services within an area.

The establishment of a Council-supported rural issues committee that includes representatives from Council, forestry companies and local communities might be a suitable forum for resolving common issues such as fire control and prevention procedures, weed and pest control, roading and landscape planning.

13.3 Knowledge gaps
  1. Identification of particular road segments expected to be used for harvesting in a five-year rolling roading strategy.
  2. Monitoring and continued research into the implementation of land-use changes: realisation of potential benefits and also of social costs.
  3. Support for the continuation of existing research into long-term environmental quality issues associated with land-use change.

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Rural Affairs Coordinator
Sector Performance Policy
MAF Policy
Ministry of Agriculture and Forestry
PO Box 2526
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NEW ZEALAND

Phone: +64 4 894 0675
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