Agriculture and forestry in savanna soils worldwide are often constrained by multiple soil limitations. We measured the effect of fertilisation on growth of Pinus caribaea var. hondurensis in order to improve savanna soil productivity in the Northern Territory, Australia. Growth responses to nitrogen, potassium, sulfur and a combined trace element treatment (abbreviated to N × K × S × T) with basal phosphorus (P) application on three soils, and N × P × K × S × T on another three soils, were examined in glasshouse factorial experiments. Without P, there was little response to N, S or T. Growth was usually greatest on N + P + S treatments. The P applications increased soil pH and growth, while N and S applications decreased pH. Growth was consistently poor at soil pH < ~5.2; a pH where exchangeable cations can be leached from the soil and aluminium can become more mobile. Responses to P, N, S and K, and likely also to zinc, were consistent with savanna soils with a long history of nutrient losses due to fire and weathering. Establishing productive plantations or agriculture will require detailed knowledge of soil properties, careful attention to soil pH and balanced fertiliser applications so as not to produce perverse outcomes. Long-term protection from fires could improve soil conditions, to be balanced against the risks of crop loss through unplanned fire.

中文翻译：

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多种土壤元素和 pH 值相互作用限制了具有长期火灾历史的热带土壤上的植物性能

全球稀树草原土壤中的农业和林业往往受到多种土壤限制的制约。我们测量了施肥对加勒比松变种生长的影响。hondurensis，以提高澳大利亚北领地的稀树草原土壤生产力。三种土壤对氮、钾、硫和微量元素处理（缩写为 N × K × S × T）和基础磷 (P) 施用的组合处理以及另外三种土壤上的 N × P × K × S × T 的生长响应，在温室析因实验中进行了检查。没有 P，对 N、S 或 T 几乎没有反应。N + P + S 处理的生长通常最大。施磷增加了土壤 pH 值和生长，而施氮和施硫降低了 pH 值。土壤 pH < ~5.2 时生长一直很差；可交换阳离子可以从土壤中浸出并且铝可以变得更易流动的 pH 值。对 P、N、S 和 K 以及可能对锌的响应与热带草原土壤一致，因为火和风化导致养分流失的历史悠久。建立生产性种植园或农业需要详细了解土壤特性、仔细注意土壤 pH 值和平衡施肥，以免产生不良后果。长期防止火灾可以改善土壤条件，以平衡因计划外火灾造成的作物损失风险。建立生产性种植园或农业需要详细了解土壤特性、仔细注意土壤 pH 值和平衡施肥，以免产生不良后果。长期防止火灾可以改善土壤条件，以平衡因计划外火灾造成的作物损失风险。建立生产性种植园或农业需要详细了解土壤特性、仔细注意土壤 pH 值和平衡施肥，以免产生不良后果。长期防止火灾可以改善土壤条件，以平衡因计划外火灾造成的作物损失风险。